Buehler, James W; Hopkins, Richard S; Overhage, J Marc; Sosin, Daniel M; Tong, Van
2004-05-07
The threat of terrorism and high-profile disease outbreaks has drawn attention to public health surveillance systems for early detection of outbreaks. State and local health departments are enhancing existing surveillance systems and developing new systems to better detect outbreaks through public health surveillance. However, information is limited about the usefulness of surveillance systems for outbreak detection or the best ways to support this function. This report supplements previous guidelines for evaluating public health surveillance systems. Use of this framework is intended to improve decision-making regarding the implementation of surveillance for outbreak detection. Use of a standardized evaluation methodology, including description of system design and operation, also will enhance the exchange of information regarding methods to improve early detection of outbreaks. The framework directs particular attention to the measurement of timeliness and validity for outbreak detection. The evaluation framework is designed to support assessment and description of all surveillance approaches to early detection, whether through traditional disease reporting, specialized analytic routines for aberration detection, or surveillance using early indicators of disease outbreaks, such as syndromic surveillance.
Faster Detection of Poliomyelitis Outbreaks to Support Polio Eradication
Chenoweth, Paul; Okayasu, Hiro; Donnelly, Christl A.; Aylward, R. Bruce; Grassly, Nicholas C.
2016-01-01
As the global eradication of poliomyelitis approaches the final stages, prompt detection of new outbreaks is critical to enable a fast and effective outbreak response. Surveillance relies on reporting of acute flaccid paralysis (AFP) cases and laboratory confirmation through isolation of poliovirus from stool. However, delayed sample collection and testing can delay outbreak detection. We investigated whether weekly testing for clusters of AFP by location and time, using the Kulldorff scan statistic, could provide an early warning for outbreaks in 20 countries. A mixed-effects regression model was used to predict background rates of nonpolio AFP at the district level. In Tajikistan and Congo, testing for AFP clusters would have resulted in an outbreak warning 39 and 11 days, respectively, before official confirmation of large outbreaks. This method has relatively high specificity and could be integrated into the current polio information system to support rapid outbreak response activities. PMID:26890053
Faster Detection of Poliomyelitis Outbreaks to Support Polio Eradication.
Blake, Isobel M; Chenoweth, Paul; Okayasu, Hiro; Donnelly, Christl A; Aylward, R Bruce; Grassly, Nicholas C
2016-03-01
As the global eradication of poliomyelitis approaches the final stages, prompt detection of new outbreaks is critical to enable a fast and effective outbreak response. Surveillance relies on reporting of acute flaccid paralysis (AFP) cases and laboratory confirmation through isolation of poliovirus from stool. However, delayed sample collection and testing can delay outbreak detection. We investigated whether weekly testing for clusters of AFP by location and time, using the Kulldorff scan statistic, could provide an early warning for outbreaks in 20 countries. A mixed-effects regression model was used to predict background rates of nonpolio AFP at the district level. In Tajikistan and Congo, testing for AFP clusters would have resulted in an outbreak warning 39 and 11 days, respectively, before official confirmation of large outbreaks. This method has relatively high specificity and could be integrated into the current polio information system to support rapid outbreak response activities.
Managing Ebola from rural to urban slum settings: experiences from Uganda.
Okware, Sam I; Omaswa, Francis; Talisuna, Ambrose; Amandua, Jacinto; Amone, Jackson; Onek, Paul; Opio, Alex; Wamala, Joseph; Lubwama, Julius; Luswa, Lukwago; Kagwa, Paul; Tylleskar, Thorkild
2015-03-01
Five outbreaks of ebola occurred in Uganda between 2000-2012. The outbreaks were quickly contained in rural areas. However, the Gulu outbreak in 2000 was the largest and complex due to insurgency. It invaded Gulu municipality and the slum- like camps of the internally displaced persons (IDPs). The Bundigugyo district outbreak followed but was detected late as a new virus. The subsequent outbreaks in the districts of Luwero district (2011, 2012) and Kibaale (2012) were limited to rural areas. Detailed records of the outbreak presentation, cases, and outcomes were reviewed and analyzed. Each outbreak was described and the outcomes examined for the different scenarios. Early detection and action provided the best outcomes and results. The ideal scenario occurred in the Luwero outbreak during which only a single case was observed. Rural outbreaks were easier to contain. The community imposed quarantine prevented the spread of ebola following introduction into Masindi district. The outbreak was confined to the extended family of the index case and only one case developed in the general population. However, the outbreak invasion of the town slum areas escalated the spread of infection in Gulu municipality. Community mobilization and leadership was vital in supporting early case detection and isolations well as contact tracing and public education. Palliative care improved survival. Focusing on treatment and not just quarantine should be emphasized as it also enhanced public trust and health seeking behavior. Early detection and action provided the best scenario for outbreak containment. Community mobilization and leadership was vital in supporting outbreak control. International collaboration was essential in supporting and augmenting the national efforts.
Taylor, Angela J; Lappi, Victoria; Wolfgang, William J; Lapierre, Pascal; Palumbo, Michael J; Medus, Carlota; Boxrud, David
2015-10-01
Salmonella enterica serovar Enteritidis is a significant cause of gastrointestinal illness in the United States; however, current molecular subtyping methods lack resolution for this highly clonal serovar. Advances in next-generation sequencing technologies have made it possible to examine whole-genome sequencing (WGS) as a potential molecular subtyping tool for outbreak detection and source trace back. Here, we conducted a retrospective analysis of S. Enteritidis isolates from seven epidemiologically confirmed foodborne outbreaks and sporadic isolates (not epidemiologically linked) to determine the utility of WGS to identify outbreaks. A collection of 55 epidemiologically characterized clinical and environmental S. Enteritidis isolates were sequenced. Single nucleotide polymorphism (SNP)-based cluster analysis of the S. Enteritidis genomes revealed well supported clades, with less than four-SNP pairwise diversity, that were concordant with epidemiologically defined outbreaks. Sporadic isolates were an average of 42.5 SNPs distant from the outbreak clusters. Isolates collected from the same patient over several weeks differed by only two SNPs. Our findings show that WGS provided greater resolution between outbreak, sporadic, and suspect isolates than the current gold standard subtyping method, pulsed-field gel electrophoresis (PFGE). Furthermore, results could be obtained in a time frame suitable for surveillance activities, supporting the use of WGS as an outbreak detection and characterization method for S. Enteritidis. Copyright © 2015, American Society for Microbiology. All Rights Reserved.
Perspectives on West Africa Ebola Virus Disease Outbreak, 2013–2016
Spengler, Jessica R.; Ervin, Elizabeth D.; Towner, Jonathan S.; Rollin, Pierre E.
2016-01-01
The variety of factors that contributed to the initial undetected spread of Ebola virus disease in West Africa during 2013–2016 and the difficulty controlling the outbreak once the etiology was identified highlight priorities for disease prevention, detection, and response. These factors include occurrence in a region recovering from civil instability and lacking experience with Ebola response; inadequate surveillance, recognition of suspected cases, and Ebola diagnosis; mobile populations and extensive urban transmission; and the community’s insufficient general understanding about the disease. The magnitude of the outbreak was not attributable to a substantial change of the virus. Continued efforts during the outbreak and in preparation for future outbreak response should involve identifying the reservoir, improving in-country detection and response capacity, conducting survivor studies and supporting survivors, engaging in culturally appropriate public education and risk communication, building productive interagency relationships, and continuing support for basic research. PMID:27070842
Perspectives on West Africa Ebola Virus Disease Outbreak, 2013-2016
Spengler, Jessica R.; Ervin, Elizabeth D.; Towner, Jonathan S.; ...
2016-06-01
The variety of factors that contributed to the initial undetected spread of Ebola virus disease in West Africa during 2013-2016 and the difficulty controlling the outbreak once the etiology was identified highlight priorities for disease prevention, detection, and response. These factors include occurrence in a region recovering from civil instability and lacking experience with Ebola response; inadequate surveillance, recognition of suspected cases, and Ebola diagnosis; mobile populations and extensive urban transmission; and the community's insufficient general understanding about the disease. The magnitude of the outbreak was not attributable to a substantial change of the virus. Finally, continued efforts during themore » outbreak and in preparation for future outbreak response should involve identifying the reservoir, improving in-country detection and response capacity, conducting survivor studies and supporting survivors, engaging in culturally appropriate public education and risk communication, building productive interagency relationships, and continuing support for basic research.« less
Perspectives on West Africa Ebola Virus Disease Outbreak, 2013-2016
DOE Office of Scientific and Technical Information (OSTI.GOV)
Spengler, Jessica R.; Ervin, Elizabeth D.; Towner, Jonathan S.
The variety of factors that contributed to the initial undetected spread of Ebola virus disease in West Africa during 2013-2016 and the difficulty controlling the outbreak once the etiology was identified highlight priorities for disease prevention, detection, and response. These factors include occurrence in a region recovering from civil instability and lacking experience with Ebola response; inadequate surveillance, recognition of suspected cases, and Ebola diagnosis; mobile populations and extensive urban transmission; and the community's insufficient general understanding about the disease. The magnitude of the outbreak was not attributable to a substantial change of the virus. Finally, continued efforts during themore » outbreak and in preparation for future outbreak response should involve identifying the reservoir, improving in-country detection and response capacity, conducting survivor studies and supporting survivors, engaging in culturally appropriate public education and risk communication, building productive interagency relationships, and continuing support for basic research.« less
Perspectives on West Africa Ebola Virus Disease Outbreak, 2013-2016.
Spengler, Jessica R; Ervin, Elizabeth D; Towner, Jonathan S; Rollin, Pierre E; Nichol, Stuart T
2016-06-01
The variety of factors that contributed to the initial undetected spread of Ebola virus disease in West Africa during 2013-2016 and the difficulty controlling the outbreak once the etiology was identified highlight priorities for disease prevention, detection, and response. These factors include occurrence in a region recovering from civil instability and lacking experience with Ebola response; inadequate surveillance, recognition of suspected cases, and Ebola diagnosis; mobile populations and extensive urban transmission; and the community's insufficient general understanding about the disease. The magnitude of the outbreak was not attributable to a substantial change of the virus. Continued efforts during the outbreak and in preparation for future outbreak response should involve identifying the reservoir, improving in-country detection and response capacity, conducting survivor studies and supporting survivors, engaging in culturally appropriate public education and risk communication, building productive interagency relationships, and continuing support for basic research.
USDA-ARS?s Scientific Manuscript database
In mid-January 2016, an outbreak of H7N8 high pathogenicity avian influenza (HPAI) virus in commercial turkeys occurred in Indiana. The outbreak was first detected by an increase in mortality followed by laboratory confirmation of H7N8 HPAI virus. Surveillance within the 10 km Control Zone detected...
A method for detecting and characterizing outbreaks of infectious disease from clinical reports.
Cooper, Gregory F; Villamarin, Ricardo; Rich Tsui, Fu-Chiang; Millett, Nicholas; Espino, Jeremy U; Wagner, Michael M
2015-02-01
Outbreaks of infectious disease can pose a significant threat to human health. Thus, detecting and characterizing outbreaks quickly and accurately remains an important problem. This paper describes a Bayesian framework that links clinical diagnosis of individuals in a population to epidemiological modeling of disease outbreaks in the population. Computer-based diagnosis of individuals who seek healthcare is used to guide the search for epidemiological models of population disease that explain the pattern of diagnoses well. We applied this framework to develop a system that detects influenza outbreaks from emergency department (ED) reports. The system diagnoses influenza in individuals probabilistically from evidence in ED reports that are extracted using natural language processing. These diagnoses guide the search for epidemiological models of influenza that explain the pattern of diagnoses well. Those epidemiological models with a high posterior probability determine the most likely outbreaks of specific diseases; the models are also used to characterize properties of an outbreak, such as its expected peak day and estimated size. We evaluated the method using both simulated data and data from a real influenza outbreak. The results provide support that the approach can detect and characterize outbreaks early and well enough to be valuable. We describe several extensions to the approach that appear promising. Copyright © 2014 Elsevier Inc. All rights reserved.
A Method for Detecting and Characterizing Outbreaks of Infectious Disease from Clinical Reports
Cooper, Gregory F.; Villamarin, Ricardo; Tsui, Fu-Chiang (Rich); Millett, Nicholas; Espino, Jeremy U.; Wagner, Michael M.
2014-01-01
Outbreaks of infectious disease can pose a significant threat to human health. Thus, detecting and characterizing outbreaks quickly and accurately remains an important problem. This paper describes a Bayesian framework that links clinical diagnosis of individuals in a population to epidemiological modeling of disease outbreaks in the population. Computer-based diagnosis of individuals who seek healthcare is used to guide the search for epidemiological models of population disease that explain the pattern of diagnoses well. We applied this framework to develop a system that detects influenza outbreaks from emergency department (ED) reports. The system diagnoses influenza in individuals probabilistically from evidence in ED reports that are extracted using natural language processing. These diagnoses guide the search for epidemiological models of influenza that explain the pattern of diagnoses well. Those epidemiological models with a high posterior probability determine the most likely outbreaks of specific diseases; the models are also used to characterize properties of an outbreak, such as its expected peak day and estimated size. We evaluated the method using both simulated data and data from a real influenza outbreak. The results provide support that the approach can detect and characterize outbreaks early and well enough to be valuable. We describe several extensions to the approach that appear promising. PMID:25181466
Automated detection of hospital outbreaks: A systematic review of methods.
Leclère, Brice; Buckeridge, David L; Boëlle, Pierre-Yves; Astagneau, Pascal; Lepelletier, Didier
2017-01-01
Several automated algorithms for epidemiological surveillance in hospitals have been proposed. However, the usefulness of these methods to detect nosocomial outbreaks remains unclear. The goal of this review was to describe outbreak detection algorithms that have been tested within hospitals, consider how they were evaluated, and synthesize their results. We developed a search query using keywords associated with hospital outbreak detection and searched the MEDLINE database. To ensure the highest sensitivity, no limitations were initially imposed on publication languages and dates, although we subsequently excluded studies published before 2000. Every study that described a method to detect outbreaks within hospitals was included, without any exclusion based on study design. Additional studies were identified through citations in retrieved studies. Twenty-nine studies were included. The detection algorithms were grouped into 5 categories: simple thresholds (n = 6), statistical process control (n = 12), scan statistics (n = 6), traditional statistical models (n = 6), and data mining methods (n = 4). The evaluation of the algorithms was often solely descriptive (n = 15), but more complex epidemiological criteria were also investigated (n = 10). The performance measures varied widely between studies: e.g., the sensitivity of an algorithm in a real world setting could vary between 17 and 100%. Even if outbreak detection algorithms are useful complementary tools for traditional surveillance, the heterogeneity in results among published studies does not support quantitative synthesis of their performance. A standardized framework should be followed when evaluating outbreak detection methods to allow comparison of algorithms across studies and synthesis of results.
Automated detection of hospital outbreaks: A systematic review of methods
Buckeridge, David L.; Lepelletier, Didier
2017-01-01
Objectives Several automated algorithms for epidemiological surveillance in hospitals have been proposed. However, the usefulness of these methods to detect nosocomial outbreaks remains unclear. The goal of this review was to describe outbreak detection algorithms that have been tested within hospitals, consider how they were evaluated, and synthesize their results. Methods We developed a search query using keywords associated with hospital outbreak detection and searched the MEDLINE database. To ensure the highest sensitivity, no limitations were initially imposed on publication languages and dates, although we subsequently excluded studies published before 2000. Every study that described a method to detect outbreaks within hospitals was included, without any exclusion based on study design. Additional studies were identified through citations in retrieved studies. Results Twenty-nine studies were included. The detection algorithms were grouped into 5 categories: simple thresholds (n = 6), statistical process control (n = 12), scan statistics (n = 6), traditional statistical models (n = 6), and data mining methods (n = 4). The evaluation of the algorithms was often solely descriptive (n = 15), but more complex epidemiological criteria were also investigated (n = 10). The performance measures varied widely between studies: e.g., the sensitivity of an algorithm in a real world setting could vary between 17 and 100%. Conclusion Even if outbreak detection algorithms are useful complementary tools for traditional surveillance, the heterogeneity in results among published studies does not support quantitative synthesis of their performance. A standardized framework should be followed when evaluating outbreak detection methods to allow comparison of algorithms across studies and synthesis of results. PMID:28441422
Matsumoto, Kayo; Hirayama, Chifumi; Sakuma, Yoko; Itoi, Yoichi; Sunadori, Asami; Kitamura, Junko; Nakahashi, Takeshi; Sugawara, Tamie; Ohkusa, Yasushi
2016-01-01
Objectives Detecting outbreaks early and then activating countermeasures based on such information is extremely important for infection control at childcare facilities. The Sumida ward began operating the Nursery School Absenteeism Surveillance System (NSASSy) in August 2013, and has since conducted real-time monitoring at nursery schools. The Public Health Center can detect outbreaks early and support appropriate intervention. This paper describes the experiences of Sumida Public Health Center related to early detection and intervention since the initiation of the system.Methods In this study, we investigated infectious disease outbreaks detected at 62 nursery schools in the Sumida ward, which were equipped with NSASSy from early November 2013 through late March 2015. We classified the information sources of the detected outbreak and responses of the public health center. The sources were (1) direct contact from some nursery schools, (2) messages from public officers with jurisdiction over nursery schools, (3) automatic detection by NSASSy, and (4) manual detection by public health center officers using NSASSy. The responses made by the health center were described and classified into 11 categories including verification of outbreak and advice for caregivers.Results The number of outbreaks detected by the aforementioned four information sources was zero, 25, 15, and 7 events, respectively, during the first 5 months after beginning NSASSy. These numbers became 5, 7, 53, and 25 events, respectively, during the subsequent 12 months. The number of outbreaks detected increased by 47% during the first 5 months, and by 87% in the following 12 months. The responses were primarily confirming the situation and offering advice to caregivers.Conclusion The Sumida Public Health Center ward could achieve early detection with automatic or manual detection of NSASSy. This system recently has become an important detection resource, and has contributed greatly to early detection. Because the Public Health Center can use it to achieve real-time monitoring, they can recognize emergent situations and intervene earlier, and thereby give feedback to the nursery schools. The system can contribute to providing effective countermeasures in these settings.
Phillips, Anastasia; Sotomayor, Cristina; Wang, Qinning; Holmes, Nadine; Furlong, Catriona; Ward, Kate; Howard, Peter; Octavia, Sophie; Lan, Ruiting; Sintchenko, Vitali
2016-09-15
Salmonella Typhimurium (STM) is an important cause of foodborne outbreaks worldwide. Subtyping of STM remains critical to outbreak investigation, yet current techniques (e.g. multilocus variable number tandem repeat analysis, MLVA) may provide insufficient discrimination. Whole genome sequencing (WGS) offers potentially greater discriminatory power to support infectious disease surveillance. We performed WGS on 62 STM isolates of a single, endemic MLVA type associated with two epidemiologically independent, food-borne outbreaks along with sporadic cases in New South Wales, Australia, during 2014. Genomes of case and environmental isolates were sequenced using HiSeq (Illumina) and the genetic distance between them was assessed by single nucleotide polymorphism (SNP) analysis. SNP analysis was compared to the epidemiological context. The WGS analysis supported epidemiological evidence and genomes of within-outbreak isolates were nearly identical. Sporadic cases differed from outbreak cases by a small number of SNPs, although their close relationship to outbreak cases may represent an unidentified common food source that may warrant further public health follow up. Previously unrecognised mini-clusters were detected. WGS of STM can discriminate foodborne community outbreaks within a single endemic MLVA clone. Our findings support the translation of WGS into public health laboratory surveillance of salmonellosis.
Pesola, A K; Parn, T; Huusko, S; Perevosčikovs, J; Ollgren, J; Salmenlinna, S; Lienemann, T; Gossner, C; Danielsson, N; Rimhanen-Finne, R
2015-05-21
A multinational outbreak of salmonellosis linked to the Riga Cup 2015 junior ice-hockey competition was detected by the Finnish health authorities in mid-April and immediately notified at the European Union level. This prompted an international outbreak investigation supported by the European Centre for Disease Prevention and Control. As of 8 May 2015, seven countries have reported 214 confirmed and suspected cases, among which 122 from Finland. The search for the source of the outbreak is ongoing.
Ali, M A; Ahsan, Z; Amin, M; Latif, S; Ayyaz, A; Ayyaz, M N
2016-05-01
Globally, disease surveillance systems are playing a significant role in outbreak detection and response management of Infectious Diseases (IDs). However, in developing countries like Pakistan, epidemic outbreaks are difficult to detect due to scarcity of public health data and absence of automated surveillance systems. Our research is intended to formulate an integrated service-oriented visual analytics architecture for ID surveillance, identify key constituents and set up a baseline for easy reproducibility of such systems in the future. This research focuses on development of ID-Viewer, which is a visual analytics decision support system for ID surveillance. It is a blend of intelligent approaches to make use of real-time streaming data from Emergency Departments (EDs) for early outbreak detection, health care resource allocation and epidemic response management. We have developed a robust service-oriented visual analytics architecture for ID surveillance, which provides automated mechanisms for ID data acquisition, outbreak detection and epidemic response management. Classification of chief-complaints is accomplished using dynamic classification module, which employs neural networks and fuzzy-logic to categorize syndromes. Standard routines by Center for Disease Control (CDC), i.e. c1-c3 (c1-mild, c2-medium and c3-ultra), and spatial scan statistics are employed for detection of temporal and spatio-temporal disease outbreaks respectively. Prediction of imminent disease threats is accomplished using support vector regression for early warnings and response planning. Geographical visual analytics displays are developed that allow interactive visualization of syndromic clusters, monitoring disease spread patterns, and identification of spatio-temporal risk zones. We analysed performance of surveillance framework using ID data for year 2011-2015. Dynamic syndromic classifier is able to classify chief-complaints to appropriate syndromes with high classification accuracy. Outbreak detection methods are able to detect the ID outbreaks in start of epidemic time zones. Prediction model is able to forecast dengue trend for 20 weeks ahead with nominal normalized root mean square error of 0.29. Interactive geo-spatiotemporal displays, i.e. heat-maps, and choropleth are shown in respective sections. The proposed framework will set a standard and provide necessary details for future implementation of such a system for resource-constrained regions. It will improve early outbreak detection attributable to natural and man-made biological threats, monitor spatio-temporal epidemic trends and provide assurance that an outbreak has, or has not occurred. Advanced analytics features will be beneficial in timely organization/formulation of health management policies, disease control activities and efficient health care resource allocation. Copyright © 2016 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.
Distribution of outbreak reporting in health care institutions by day of the week.
Amirov, Chingiz; Walton, Ryan N; Ahmed, Sarah; Binns, Malcolm A; Van Toen, Jane E; Candon, Heather L
2012-12-01
The notion that outbreaks are more likely to occur on Friday is prevalent among staff in health care institutions. However, there is little evidence to support or discredit this notion. We postulated that outbreaks were no more likely to be reported on any particular day of the week. A total of 901 institutional outbreaks in Toronto health care facilities were tabulated according to type, outbreak setting, and day of the week reported. A χ(2) goodness-of-fit test compared daily values for 7-day per week and 5-day per week periods. Post hoc partitioning was used to pinpoint specific day(s) of the week that differed significantly. Fewer outbreaks were reported on Saturdays and Sundays. Further analysis examined the distribution of outbreak reporting specifically focusing on the Monday to Friday weekday period. Among the weekdays, higher proportions of outbreaks were reported on Mondays and Fridays. Our null hypothesis was rejected. Overall, Mondays and Fridays had the highest occurrence of outbreak reporting. We suggest that this might be due to "deadline" and "catch-up" reporting related to the "weekend effect," whereby structural differences in weekend staffing affect detection of outbreaks. Such delays warrant reexamination of surveillance processes for timely outbreak detection independent of calendar cycle. Copyright © 2012 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Mosby, Inc. All rights reserved.
Hewitt, K A; Nalabanda, A; Cassell, J A
2015-05-01
Scabies is an important public health problem in residential care homes. Delayed diagnosis contributes to outbreaks, which may be prolonged and difficult to control. We investigated factors influencing outbreak recognition, diagnosis and treatment, and staff experiences of outbreak control, identifying areas for intervention. We carried out a semi-structured survey of managers, affected residents and staff of seven care homes reporting suspected scabies outbreaks in southern England over a 6-month period. Attack rates ranged from 2% to 50%, and most cases had dementia (37/39, 95%). Cases were diagnosed clinically by GPs (59%) or home staff (41%), none by dermatologists. Most outbreaks were attributable to avoidably late diagnosis of the index case. Participants reported considerable challenges in managing scabies outbreaks, including late diagnosis and recognition of outbreaks; logistically difficult mass treatment; distressing treatment processes and high costs. This study demonstrates the need for improved support for care homes in detecting and managing these outbreaks.
Girond, Florian; Randrianasolo, Laurence; Randriamampionona, Lea; Rakotomanana, Fanjasoa; Randrianarivelojosia, Milijaona; Ratsitorahina, Maherisoa; Brou, Télesphore Yao; Herbreteau, Vincent; Mangeas, Morgan; Zigiumugabe, Sixte; Hedje, Judith; Rogier, Christophe; Piola, Patrice
2017-02-13
The use of a malaria early warning system (MEWS) to trigger prompt public health interventions is a key step in adding value to the epidemiological data routinely collected by sentinel surveillance systems. This study describes a system using various epidemic thresholds and a forecasting component with the support of new technologies to improve the performance of a sentinel MEWS. Malaria-related data from 21 sentinel sites collected by Short Message Service are automatically analysed to detect malaria trends and malaria outbreak alerts with automated feedback reports. Roll Back Malaria partners can, through a user-friendly web-based tool, visualize potential outbreaks and generate a forecasting model. The system already demonstrated its ability to detect malaria outbreaks in Madagascar in 2014. This approach aims to maximize the usefulness of a sentinel surveillance system to predict and detect epidemics in limited-resource environments.
Yano, Terdsak; Phornwisetsirikun, Somphorn; Susumpow, Patipat; Visrutaratna, Surasing; Chanachai, Karoon; Phetra, Polawat; Chaisowwong, Warangkhana; Trakarnsirinont, Pairat; Hemwan, Phonpat; Kaewpinta, Boontuan; Singhapreecha, Charuk; Kreausukon, Khwanchai; Charoenpanyanet, Arisara ; Robert, Chongchit Sripun; Robert, Lamar; Rodtian, Pranee; Mahasing, Suteerat; Laiya, Ekkachai; Pattamakaew, Sakulrat; Tankitiyanon, Taweesart; Sansamur, Chalutwan
2018-01-01
Background Aiming for early disease detection and prompt outbreak control, digital technology with a participatory One Health approach was used to create a novel disease surveillance system called Participatory One Health Disease Detection (PODD). PODD is a community-owned surveillance system that collects data from volunteer reporters; identifies disease outbreak automatically; and notifies the local governments (LGs), surrounding villages, and relevant authorities. This system provides a direct and immediate benefit to the communities by empowering them to protect themselves. Objective The objective of this study was to determine the effectiveness of the PODD system for the rapid detection and control of disease outbreaks. Methods The system was piloted in 74 LGs in Chiang Mai, Thailand, with the participation of 296 volunteer reporters. The volunteers and LGs were key participants in the piloting of the PODD system. Volunteers monitored animal and human diseases, as well as environmental problems, in their communities and reported these events via the PODD mobile phone app. LGs were responsible for outbreak control and provided support to the volunteers. Outcome mapping was used to evaluate the performance of the LGs and volunteers. Results LGs were categorized into one of the 3 groups based on performance: A (good), B (fair), and C (poor), with the majority (46%,34/74) categorized into group B. Volunteers were similarly categorized into 4 performance groups (A-D), again with group A showing the best performance, with the majority categorized into groups B and C. After 16 months of implementation, 1029 abnormal events had been reported and confirmed to be true reports. The majority of abnormal reports were sick or dead animals (404/1029, 39.26%), followed by zoonoses and other human diseases (129/1029, 12.54%). Many potentially devastating animal disease outbreaks were detected and successfully controlled, including 26 chicken high mortality outbreaks, 4 cattle disease outbreaks, 3 pig disease outbreaks, and 3 fish disease outbreaks. In all cases, the communities and animal authorities cooperated to apply community contingency plans to control these outbreaks, and community volunteers continued to monitor the abnormal events for 3 weeks after each outbreak was controlled. Conclusions By design, PODD initially targeted only animal diseases that potentially could emerge into human pandemics (eg, avian influenza) and then, in response to community needs, expanded to cover human health and environmental health issues. PMID:29563079
Daughton, Ashlynn R; Velappan, Nileena; Abeyta, Esteban; Priedhorsky, Reid; Deshpande, Alina
2016-01-01
Influenza causes significant morbidity and mortality each year, with 2-8% of weekly outpatient visits around the United States for influenza-like-illness (ILI) during the peak of the season. Effective use of existing flu surveillance data allows officials to understand and predict current flu outbreaks and can contribute to reductions in influenza morbidity and mortality. Previous work used the 2009-2010 influenza season to investigate the possibility of using existing military and civilian surveillance systems to improve early detection of flu outbreaks. Results suggested that civilian surveillance could help predict outbreak trajectory in local military installations. To further test that hypothesis, we compare pairs of civilian and military outbreaks in seven locations between 2000 and 2013. We find no predictive relationship between outbreak peaks or time series of paired outbreaks. This larger study does not find evidence to support the hypothesis that civilian data can be used as sentinel surveillance for military installations. We additionally investigate the effect of modifying the ILI case definition between the standard Department of Defense definition, a more specific definition proposed in literature, and confirmed Influenza A. We find that case definition heavily impacts results. This study thus highlights the importance of careful selection of case definition, and appropriate consideration of case definition in the interpretation of results.
Benowitz, Isaac; Fitzhenry, Robert; Boyd, Christopher; Dickinson, Michelle; Levy, Michael; Lin, Ying; Nazarian, Elizabeth; Ostrowsky, Belinda; Passaretti, Teresa; Rakeman, Jennifer; Saylors, Amy; Shamoonian, Elena; Smith, Terry-Ann; Balter, Sharon
2018-04-01
We investigated an outbreak of eight Legionnaires' disease cases among persons living in an urban residential community of 60,000 people. Possible environmental sources included two active cooling towers (air-conditioning units for large buildings) <1 km from patient residences, a market misting system, a community-wide water system used for heating and cooling, and potable water. To support a timely public health response, we used real-time polymerase chain reaction (PCR) to identify Legionella DNA in environmental samples within hours of specimen collection. We detected L. pneumophila serogroup 1 DNA only at a power plant cooling tower, supporting the decision to order remediation before culture results were available. An isolate from a power plant cooling tower sample was indistinguishable from a patient isolate by pulsed-field gel electrophoresis, suggesting the cooling tower was the outbreak source. PCR results were available <1 day after sample collection, and culture results were available as early as 5 days after plating. PCR is a valuable tool for identifying Legionella DNA in environmental samples in outbreak settings.
Satellite data based method for general survey of forest insect disturbance in British Columbia
NASA Astrophysics Data System (ADS)
Ranson, J.; Montesano, P.
2008-12-01
Regional forest disturbances caused by insects are important to monitor and quantify because of their influence on local ecosystems and the global carbon cycle. Local damage to forest trees disrupts food supplies and shelter for a variety of organisms. Changes in the global carbon budget, its sources and its sinks affect the way the earth functions as a whole, and has an impact on global climate. Furthermore, the ability to detect nascent outbreaks and monitor the spread of regional infestations helps managers mitigate the damage done by catastrophic insect outbreaks. While detection is needed at a fine scale to support local mitigation efforts, detection at a broad regional scale is important for carbon flux modeling on the landscape scale, and needed to direct the local efforts. This paper presents a method for routinely detecting insect damage to coniferous forests using MODIS vegetation indices, thermal anomalies and land cover. The technique is validated using insect outbreak maps and accounts for fire disturbance effects. The range of damage detected may be used to interpret and quantify possible forest damage by insects.
in silico Surveillance: evaluating outbreak detection with simulation models
2013-01-01
Background Detecting outbreaks is a crucial task for public health officials, yet gaps remain in the systematic evaluation of outbreak detection protocols. The authors’ objectives were to design, implement, and test a flexible methodology for generating detailed synthetic surveillance data that provides realistic geographical and temporal clustering of cases and use to evaluate outbreak detection protocols. Methods A detailed representation of the Boston area was constructed, based on data about individuals, locations, and activity patterns. Influenza-like illness (ILI) transmission was simulated, producing 100 years of in silico ILI data. Six different surveillance systems were designed and developed using gathered cases from the simulated disease data. Performance was measured by inserting test outbreaks into the surveillance streams and analyzing the likelihood and timeliness of detection. Results Detection of outbreaks varied from 21% to 95%. Increased coverage did not linearly improve detection probability for all surveillance systems. Relaxing the decision threshold for signaling outbreaks greatly increased false-positives, improved outbreak detection slightly, and led to earlier outbreak detection. Conclusions Geographical distribution can be more important than coverage level. Detailed simulations of infectious disease transmission can be configured to represent nearly any conceivable scenario. They are a powerful tool for evaluating the performance of surveillance systems and methods used for outbreak detection. PMID:23343523
Mavridis, Konstantinos; Fotakis, Emmanouil A; Kioulos, Ilias; Mpellou, Spiridoula; Konstantas, Spiros; Varela, Evangelia; Gewehr, Sandra; Diamantopoulos, Vasilis; Vontas, John
2018-06-01
During July-October 2017 a WNV outbreak took place in the Peloponnese, Southern Greece with five confirmed deaths. During routine monitoring survey in the Peloponnese, supported by the local Prefecture, we have confirmed the presence of all three Culex pipiens biotypes in the region, with a high percentage of Culex pipiens/molestus hybrids (37.0%) which are considered a highly competent vector of WNV. Kdr mutations related to pyrethroid resistance were found at relatively low levels (14.3% homozygosity) while no mosquitoes harboring the recently identified chitin synthase diflubenzuron-resistance mutations were detected in the region. As an immediate action, following the disease outbreak (within days), we collected a large number of mosquitoes using CO 2 CDC traps from the villages in the Argolis area of the Peloponnese, where high incidence of WNV human infections were reported. WNV lineage 2 was detected in 3 out of 47 Cx. pipiens mosquito pools (detection rate = 6.38%). The virus was not detected in any other mosquito species, such as Aedes albopictus, sampled from the region at the time of the disease outbreak. Our results show that detection of WNV lineage 2 in Cx. pipiens pools is spatially and chronologically associated with human clinical cases, thus implicating Cx. pipiens mosquitoes as the most likely WNV vector. The absence of diflubenzuron resistance mutations and the low frequency of pyrethroid (kdr) resistance mutations indicates the suitability of these insecticides for Cx. pipiens control, in the format of larvicides and/or residual spraying applications respectively, which was indeed the main (evidence based) response, following the disease outbreak. Copyright © 2018 Elsevier B.V. All rights reserved.
Daughton, Ashlynn R.; Velappan, Nileena; Abeyta, Esteban; ...
2016-07-08
Influenza causes significant morbidity and mortality each year, with 2–8% of weekly outpatient visits around the United States for influenza-like-illness (ILI) during the peak of the season. Effective use of existing flu surveillance data allows officials to understand and predict current flu outbreaks and can contribute to reductions in influenza morbidity and mortality. Previous work used the 2009–2010 influenza season to investigate the possibility of using existing military and civilian surveillance systems to improve early detection of flu outbreaks. Results suggested that civilian surveillance could help predict outbreak trajectory in local military installations. To further test that hypothesis, we comparemore » pairs of civilian and military outbreaks in seven locations between 2000 and 2013. We find no predictive relationship between outbreak peaks or time series of paired outbreaks. This larger study does not find evidence to support the hypothesis that civilian data can be used as sentinel surveillance for military installations. We additionally investigate the effect of modifying the ILI case definition between the standard Department of Defense definition, a more specific definition proposed in literature, and confirmed Influenza A. We find that case definition heavily impacts results. In conclusion, this study thus highlights the importance of careful selection of case definition, and appropriate consideration of case definition in the interpretation of results.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Daughton, Ashlynn R.; Velappan, Nileena; Abeyta, Esteban
Influenza causes significant morbidity and mortality each year, with 2–8% of weekly outpatient visits around the United States for influenza-like-illness (ILI) during the peak of the season. Effective use of existing flu surveillance data allows officials to understand and predict current flu outbreaks and can contribute to reductions in influenza morbidity and mortality. Previous work used the 2009–2010 influenza season to investigate the possibility of using existing military and civilian surveillance systems to improve early detection of flu outbreaks. Results suggested that civilian surveillance could help predict outbreak trajectory in local military installations. To further test that hypothesis, we comparemore » pairs of civilian and military outbreaks in seven locations between 2000 and 2013. We find no predictive relationship between outbreak peaks or time series of paired outbreaks. This larger study does not find evidence to support the hypothesis that civilian data can be used as sentinel surveillance for military installations. We additionally investigate the effect of modifying the ILI case definition between the standard Department of Defense definition, a more specific definition proposed in literature, and confirmed Influenza A. We find that case definition heavily impacts results. In conclusion, this study thus highlights the importance of careful selection of case definition, and appropriate consideration of case definition in the interpretation of results.« less
Velappan, Nileena; Abeyta, Esteban; Priedhorsky, Reid; Deshpande, Alina
2016-01-01
Influenza causes significant morbidity and mortality each year, with 2–8% of weekly outpatient visits around the United States for influenza-like-illness (ILI) during the peak of the season. Effective use of existing flu surveillance data allows officials to understand and predict current flu outbreaks and can contribute to reductions in influenza morbidity and mortality. Previous work used the 2009–2010 influenza season to investigate the possibility of using existing military and civilian surveillance systems to improve early detection of flu outbreaks. Results suggested that civilian surveillance could help predict outbreak trajectory in local military installations. To further test that hypothesis, we compare pairs of civilian and military outbreaks in seven locations between 2000 and 2013. We find no predictive relationship between outbreak peaks or time series of paired outbreaks. This larger study does not find evidence to support the hypothesis that civilian data can be used as sentinel surveillance for military installations. We additionally investigate the effect of modifying the ILI case definition between the standard Department of Defense definition, a more specific definition proposed in literature, and confirmed Influenza A. We find that case definition heavily impacts results. This study thus highlights the importance of careful selection of case definition, and appropriate consideration of case definition in the interpretation of results. PMID:27391232
Hot spots in a wired world: WHO surveillance of emerging and re-emerging infectious diseases.
Heymann, D L; Rodier, G R
2001-12-01
The resurgence of the microbial threat, rooted in several recent trends, has increased the vulnerability of all nations to the risk of infectious diseases, whether newly emerging, well-established, or deliberately caused. Infectious disease intelligence, gleaned through sensitive surveillance, is the best defence. The epidemiological and laboratory techniques needed to detect, investigate, and contain a deliberate outbreak are the same as those used for natural outbreaks. In April 2000, WHO formalised an infrastructure (the Global Outbreak Alert and Response Network) for responding to the heightened need for early awareness of outbreaks and preparedness to respond. The Network, which unites 110 existing networks, is supported by several new mechanisms and a computer-driven tool for real time gathering of disease intelligence. The procedure for outbreak alert and response has four phases: systematic detection, outbreak verification, real time alerts, and rapid response. For response, the framework uses different strategies for combating known risks and unexpected events, and for improving both global and national preparedness. New forces at work in an electronically interconnected world are beginning to break down the traditional reluctance of countries to report outbreaks due to fear of the negative impact on trade and tourism. About 65% of the world's first news about infectious disease events now comes from informal sources, including press reports and the internet.
IMANISHI, M.; NEWTON, A. E.; VIEIRA, A. R.; GONZALEZ-AVILES, G.; KENDALL SCOTT, M. E.; MANIKONDA, K.; MAXWELL, T. N.; HALPIN, J. L.; FREEMAN, M. M.; MEDALLA, F.; AYERS, T. L.; DERADO, G.; MAHON, B. E.; MINTZ, E. D.
2016-01-01
SUMMARY Although rare, typhoid fever cases acquired in the United States continue to be reported. Detection and investigation of outbreaks in these domestically acquired cases offer opportunities to identify chronic carriers. We searched surveillance and laboratory databases for domestically acquired typhoid fever cases, used a space–time scan statistic to identify clusters, and classified clusters as outbreaks or non-outbreaks. From 1999 to 2010, domestically acquired cases accounted for 18% of 3373 reported typhoid fever cases; their isolates were less often multidrug-resistant (2% vs. 15%) compared to isolates from travel-associated cases. We identified 28 outbreaks and two possible outbreaks within 45 space–time clusters of ⩾2 domestically acquired cases, including three outbreaks involving ⩾2 molecular subtypes. The approach detected seven of the ten outbreaks published in the literature or reported to CDC. Although this approach did not definitively identify any previously unrecognized outbreaks, it showed the potential to detect outbreaks of typhoid fever that may escape detection by routine analysis of surveillance data. Sixteen outbreaks had been linked to a carrier. Every case of typhoid fever acquired in a non-endemic country warrants thorough investigation. Space–time scan statistics, together with shoe-leather epidemiology and molecular subtyping, may improve outbreak detection. PMID:25427666
Imanishi, M; Newton, A E; Vieira, A R; Gonzalez-Aviles, G; Kendall Scott, M E; Manikonda, K; Maxwell, T N; Halpin, J L; Freeman, M M; Medalla, F; Ayers, T L; Derado, G; Mahon, B E; Mintz, E D
2015-08-01
Although rare, typhoid fever cases acquired in the United States continue to be reported. Detection and investigation of outbreaks in these domestically acquired cases offer opportunities to identify chronic carriers. We searched surveillance and laboratory databases for domestically acquired typhoid fever cases, used a space-time scan statistic to identify clusters, and classified clusters as outbreaks or non-outbreaks. From 1999 to 2010, domestically acquired cases accounted for 18% of 3373 reported typhoid fever cases; their isolates were less often multidrug-resistant (2% vs. 15%) compared to isolates from travel-associated cases. We identified 28 outbreaks and two possible outbreaks within 45 space-time clusters of ⩾2 domestically acquired cases, including three outbreaks involving ⩾2 molecular subtypes. The approach detected seven of the ten outbreaks published in the literature or reported to CDC. Although this approach did not definitively identify any previously unrecognized outbreaks, it showed the potential to detect outbreaks of typhoid fever that may escape detection by routine analysis of surveillance data. Sixteen outbreaks had been linked to a carrier. Every case of typhoid fever acquired in a non-endemic country warrants thorough investigation. Space-time scan statistics, together with shoe-leather epidemiology and molecular subtyping, may improve outbreak detection.
Thomas, Lian F; Bishop, Richard P; Onzere, Cynthia; Mcintosh, Michael T; Lemire, Karissa A; de Glanville, William A; Cook, E Anne J; Fèvre, Eric M
2016-09-08
African swine fever (ASF), caused by African swine fever virus (ASFV), is a severe haemorrhagic disease of pigs, outbreaks of which can have a devastating impact upon commercial and small-holder pig production. Pig production in western Kenya is characterised by low-input, free-range systems practised by poor farmers keeping between two and ten pigs. These farmers are particularly vulnerable to the catastrophic loss of livestock assets experienced in an ASF outbreak. This study wished to expand our understanding of ASFV epidemiology during a period when no outbreaks were reported. Two hundred and seventy six whole blood samples were analysed using two independent conventional and real time PCR assays to detect ASFV. Despite no recorded outbreak of clinical ASF during this time, virus was detected in 90/277 samples analysed by conventional PCR and 142/209 samples analysed by qPCR. Genotyping of a sub-set of these samples indicated that the viruses associated with the positive samples were classified within genotype IX and that these strains were therefore genetically similar to the virus associated with the 2006/2007 ASF outbreaks in Kenya. The detection of ASFV viral DNA in a relatively high number of pigs delivered for slaughter during a period with no reported outbreaks provides support for two hypotheses, which are not mutually exclusive: (1) that virus prevalence may be over-estimated by slaughter-slab sampling, relative to that prevailing in the wider pig population; (2) that sub-clinical, chronically infected or recovered pigs may be responsible for persistence of the virus in endemic areas.
Benowitz, Isaac; Fitzhenry, Robert; Boyd, Christopher; Dickinson, Michelle; Levy, Michael; Lin, Ying; Nazarian, Elizabeth; Ostrowsky, Belinda; Passaretti, Teresa; Rakeman, Jennifer; Saylors, Amy; Shamoonian, Elena; Smith, Terry-Ann; Balter, Sharon
2018-01-01
We investigated an outbreak of eight Legionnaires’ disease cases among persons living in an urban residential community of 60,000 people. Possible environmental sources included two active cooling towers (air-conditioning units for large buildings) <1 km from patient residences, a market misting system, a community-wide water system used for heating and cooling, and potable water. To support a timely public health response, we used real-time polymerase chain reaction (PCR) to identify Legionella DNA in environmental samples within hours of specimen collection. We detected L. pneumophila serogroup 1 DNA only at a power plant cooling tower, supporting the decision to order remediation before culture results were available. An isolate from a power plant cooling tower sample was indistinguishable from a patient isolate by pulsed-field gel electrophoresis, suggesting the cooling tower was the outbreak source. PCR results were available <1 day after sample collection, and culture results were available as early as 5 days after plating. PCR is a valuable tool for identifying Legionella DNA in environmental samples in outbreak settings. PMID:29780175
Baker, Arthur W; Haridy, Salah; Salem, Joseph; Ilieş, Iulian; Ergai, Awatef O; Samareh, Aven; Andrianas, Nicholas; Benneyan, James C; Sexton, Daniel J; Anderson, Deverick J
2017-11-24
Traditional strategies for surveillance of surgical site infections (SSI) have multiple limitations, including delayed and incomplete outbreak detection. Statistical process control (SPC) methods address these deficiencies by combining longitudinal analysis with graphical presentation of data. We performed a pilot study within a large network of community hospitals to evaluate performance of SPC methods for detecting SSI outbreaks. We applied conventional Shewhart and exponentially weighted moving average (EWMA) SPC charts to 10 previously investigated SSI outbreaks that occurred from 2003 to 2013. We compared the results of SPC surveillance to the results of traditional SSI surveillance methods. Then, we analysed the performance of modified SPC charts constructed with different outbreak detection rules, EWMA smoothing factors and baseline SSI rate calculations. Conventional Shewhart and EWMA SPC charts both detected 8 of the 10 SSI outbreaks analysed, in each case prior to the date of traditional detection. Among detected outbreaks, conventional Shewhart chart detection occurred a median of 12 months prior to outbreak onset and 22 months prior to traditional detection. Conventional EWMA chart detection occurred a median of 7 months prior to outbreak onset and 14 months prior to traditional detection. Modified Shewhart and EWMA charts additionally detected several outbreaks earlier than conventional SPC charts. Shewhart and SPC charts had low false-positive rates when used to analyse separate control hospital SSI data. Our findings illustrate the potential usefulness and feasibility of real-time SPC surveillance of SSI to rapidly identify outbreaks and improve patient safety. Further study is needed to optimise SPC chart selection and calculation, statistical outbreak detection rules and the process for reacting to signals of potential outbreaks. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
The Global Outbreak Alert and Response Network
Mackenzie, John S.; Drury, Patrick; Arthur, Ray R.; Ryan, Michael J.; Grein, Thomas; Slattery, Raphael; Suri, Sameera; Domingo, Christine Tiffany; Bejtullahu, Armand
2014-01-01
The Global Outbreak Alert and Response Network (GOARN) was established in 2000 as a network of technical institutions, research institutes, universities, international health organisations and technical networks willing to contribute and participate in internationally coordinated responses to infectious disease outbreaks. It reflected a recognition of the need to strengthen and coordinate rapid mobilisation of experts in responding to international outbreaks and to overcome the sometimes chaotic and fragmented operations characterising previous responses. The network partners agreed that the World Health Organization would coordinate the network and provide a secretariat, which would also function as the operational support team. The network has evolved to comprise 153 institutions/technical partners and 37 additional networks, the latter encompassing a further 355 members and has been directly involved in 137 missions to 79 countries, territories or areas. Future challenges will include supporting countries to achieve the capacity to detect and respond to outbreaks of international concern, as required by the International Health Regulations (2005). GOARN's increasing regional focus and expanding geographic composition will be central to meeting these challenges. The paper summarises some of network's achievements over the past 13 years and presents some of the future challenges. PMID:25186571
The global outbreak alert and response network.
Mackenzie, John S; Drury, Patrick; Arthur, Ray R; Ryan, Michael J; Grein, Thomas; Slattery, Raphael; Suri, Sameera; Domingo, Christine Tiffany; Bejtullahu, Armand
2014-01-01
The Global Outbreak Alert and Response Network (GOARN) was established in 2000 as a network of technical institutions, research institutes, universities, international health organisations and technical networks willing to contribute and participate in internationally coordinated responses to infectious disease outbreaks. It reflected a recognition of the need to strengthen and coordinate rapid mobilisation of experts in responding to international outbreaks and to overcome the sometimes chaotic and fragmented operations characterising previous responses. The network partners agreed that the World Health Organization would coordinate the network and provide a secretariat, which would also function as the operational support team. The network has evolved to comprise 153 institutions/technical partners and 37 additional networks, the latter encompassing a further 355 members and has been directly involved in 137 missions to 79 countries, territories or areas. Future challenges will include supporting countries to achieve the capacity to detect and respond to outbreaks of international concern, as required by the International Health Regulations (2005). GOARN's increasing regional focus and expanding geographic composition will be central to meeting these challenges. The paper summarises some of network's achievements over the past 13 years and presents some of the future challenges.
Yano, Terdsak; Phornwisetsirikun, Somphorn; Susumpow, Patipat; Visrutaratna, Surasing; Chanachai, Karoon; Phetra, Polawat; Chaisowwong, Warangkhana; Trakarnsirinont, Pairat; Hemwan, Phonpat; Kaewpinta, Boontuan; Singhapreecha, Charuk; Kreausukon, Khwanchai; Charoenpanyanet, Arisara; Robert, Chongchit Sripun; Robert, Lamar; Rodtian, Pranee; Mahasing, Suteerat; Laiya, Ekkachai; Pattamakaew, Sakulrat; Tankitiyanon, Taweesart; Sansamur, Chalutwan; Srikitjakarn, Lertrak
2018-03-21
Aiming for early disease detection and prompt outbreak control, digital technology with a participatory One Health approach was used to create a novel disease surveillance system called Participatory One Health Disease Detection (PODD). PODD is a community-owned surveillance system that collects data from volunteer reporters; identifies disease outbreak automatically; and notifies the local governments (LGs), surrounding villages, and relevant authorities. This system provides a direct and immediate benefit to the communities by empowering them to protect themselves. The objective of this study was to determine the effectiveness of the PODD system for the rapid detection and control of disease outbreaks. The system was piloted in 74 LGs in Chiang Mai, Thailand, with the participation of 296 volunteer reporters. The volunteers and LGs were key participants in the piloting of the PODD system. Volunteers monitored animal and human diseases, as well as environmental problems, in their communities and reported these events via the PODD mobile phone app. LGs were responsible for outbreak control and provided support to the volunteers. Outcome mapping was used to evaluate the performance of the LGs and volunteers. LGs were categorized into one of the 3 groups based on performance: A (good), B (fair), and C (poor), with the majority (46%,34/74) categorized into group B. Volunteers were similarly categorized into 4 performance groups (A-D), again with group A showing the best performance, with the majority categorized into groups B and C. After 16 months of implementation, 1029 abnormal events had been reported and confirmed to be true reports. The majority of abnormal reports were sick or dead animals (404/1029, 39.26%), followed by zoonoses and other human diseases (129/1029, 12.54%). Many potentially devastating animal disease outbreaks were detected and successfully controlled, including 26 chicken high mortality outbreaks, 4 cattle disease outbreaks, 3 pig disease outbreaks, and 3 fish disease outbreaks. In all cases, the communities and animal authorities cooperated to apply community contingency plans to control these outbreaks, and community volunteers continued to monitor the abnormal events for 3 weeks after each outbreak was controlled. By design, PODD initially targeted only animal diseases that potentially could emerge into human pandemics (eg, avian influenza) and then, in response to community needs, expanded to cover human health and environmental health issues. ©Terdsak Yano, Somphorn Phornwisetsirikun, Patipat Susumpow, Surasing Visrutaratna, Karoon Chanachai, Polawat Phetra, Warangkhana Chaisowwong, Pairat Trakarnsirinont, Phonpat Hemwan, Boontuan Kaewpinta, Charuk Singhapreecha, Khwanchai Kreausukon, Arisara Charoenpanyanet, Chongchit Sripun Robert, Lamar Robert, Pranee Rodtian, Suteerat Mahasing, Ekkachai Laiya, Sakulrat Pattamakaew, Taweesart Tankitiyanon, Chalutwan Sansamur, Lertrak Srikitjakarn. Originally published in JMIR Public Health and Surveillance (http://publichealth.jmir.org), 21.03.2018.
Bio-ALIRT biosurveillance detection algorithm evaluation.
Siegrist, David; Pavlin, J
2004-09-24
Early detection of disease outbreaks by a medical biosurveillance system relies on two major components: 1) the contribution of early and reliable data sources and 2) the sensitivity, specificity, and timeliness of biosurveillance detection algorithms. This paper describes an effort to assess leading detection algorithms by arranging a common challenge problem and providing a common data set. The objectives of this study were to determine whether automated detection algorithms can reliably and quickly identify the onset of natural disease outbreaks that are surrogates for possible terrorist pathogen releases, and do so at acceptable false-alert rates (e.g., once every 2-6 weeks). Historic de-identified data were obtained from five metropolitan areas over 23 months; these data included International Classification of Diseases, Ninth Revision (ICD-9) codes related to respiratory and gastrointestinal illness syndromes. An outbreak detection group identified and labeled two natural disease outbreaks in these data and provided them to analysts for training of detection algorithms. All outbreaks in the remaining test data were identified but not revealed to the detection groups until after their analyses. The algorithms established a probability of outbreak for each day's counts. The probability of outbreak was assessed as an "actual" alert for different false-alert rates. The best algorithms were able to detect all of the outbreaks at false-alert rates of one every 2-6 weeks. They were often able to detect for the same day human investigators had identified as the true start of the outbreak. Because minimal data exists for an actual biologic attack, determining how quickly an algorithm might detect such an attack is difficult. However, application of these algorithms in combination with other data-analysis methods to historic outbreak data indicates that biosurveillance techniques for analyzing syndrome counts can rapidly detect seasonal respiratory and gastrointestinal illness outbreaks. Further research is needed to assess the value of electronic data sources for predictive detection. In addition, simulations need to be developed and implemented to better characterize the size and type of biologic attack that can be detected by current methods by challenging them under different projected operational conditions.
Li, John; Smith, Kirk; Kaehler, Dawn; Everstine, Karen; Rounds, Josh; Hedberg, Craig
2010-11-01
Foodborne outbreaks are detected by recognition of similar illnesses among persons with a common exposure or by identification of case clusters through pathogen-specific surveillance. PulseNet USA has created a national framework for pathogen-specific surveillance, but no comparable effort has been made to improve surveillance of consumer complaints of suspected foodborne illness. The purpose of this study was to characterize the complaint surveillance system in Minnesota and to evaluate its use for detecting outbreaks. Minnesota Department of Health foodborne illness surveillance data from 2000 through 2006 were analyzed for this study. During this period, consumer complaint surveillance led to detection of 79% of confirmed foodborne outbreaks. Most norovirus infection outbreaks were detected through complaints. Complaint surveillance also directly led or contributed to detection of 25% of salmonellosis outbreaks. Eighty-one percent of complainants did not seek medical attention. The number of ill persons in a complainant's party was significantly associated with a complaint ultimately resulting in identification of a foodborne outbreak. Outbreak confirmation was related to a complainant's ability to identify a common exposure and was likely related to the process by which the Minnesota Department of Health chooses complaints to investigate. A significant difference (P < 0.001) was found in incubation periods between complaints that were outbreak associated (median, 27 h) and those that were not outbreak associated (median, 6 h). Complaint systems can be used to detect outbreaks caused by a variety of pathogens. Case detection for foodborne disease surveillance in Minnesota happens through a multitude of mechanisms. The ability to integrate these mechanisms and carry out rapid investigations leads to improved outbreak detection.
Detection and forecasting of oyster norovirus outbreaks: recent advances and future perspectives.
Wang, Jiao; Deng, Zhiqiang
2012-09-01
Norovirus is a highly infectious pathogen that is commonly found in oysters growing in fecally contaminated waters. Norovirus outbreaks can cause the closure of oyster harvesting waters and acute gastroenteritis in humans associated with consumption of contaminated raw oysters. Extensive efforts and progresses have been made in detection and forecasting of oyster norovirus outbreaks over the past decades. The main objective of this paper is to provide a literature review of methods and techniques for detecting and forecasting oyster norovirus outbreaks and thereby to identify the future directions for improving the detection and forecasting of norovirus outbreaks. It is found that (1) norovirus outbreaks display strong seasonality with the outbreak peak occurring commonly in December-March in the U.S. and April-May in the Europe; (2) norovirus outbreaks are affected by multiple environmental factors, including but not limited to precipitation, temperature, solar radiation, wind, and salinity; (3) various modeling approaches may be employed to forecast norovirus outbreaks, including Bayesian models, regression models, Artificial Neural Networks, and process-based models; and (4) diverse techniques are available for near real-time detection of norovirus outbreaks, including multiplex PCR, seminested PCR, real-time PCR, quantitative PCR, and satellite remote sensing. The findings are important to the management of oyster growing waters and to future investigations into norovirus outbreaks. It is recommended that a combined approach of sensor-assisted real time monitoring and modeling-based forecasting should be utilized for an efficient and effective detection and forecasting of norovirus outbreaks caused by consumption of contaminated oysters. Copyright © 2012 Elsevier Ltd. All rights reserved.
2011-01-01
Fragile states are home to a sixth of the world's population, and their populations are particularly vulnerable to infectious disease outbreaks. Timely surveillance and control are essential to minimise the impact of these outbreaks, but little evidence is published about the effectiveness of existing surveillance systems. We did a systematic review of the circumstances (mode) of detection of outbreaks occurring in 22 fragile states in the decade 2000-2010 (i.e. all states consistently meeting fragility criteria during the timeframe of the review), as well as time lags from onset to detection of these outbreaks, and from detection to further events in their timeline. The aim of this review was to enhance the evidence base for implementing infectious disease surveillance in these complex, resource-constrained settings, and to assess the relative importance of different routes whereby outbreak detection occurs. We identified 61 reports concerning 38 outbreaks. Twenty of these were detected by existing surveillance systems, but 10 detections occurred following formal notifications by participating health facilities rather than data analysis. A further 15 outbreaks were detected by informal notifications, including rumours. There were long delays from onset to detection (median 29 days) and from detection to further events (investigation, confirmation, declaration, control). Existing surveillance systems yielded the shortest detection delays when linked to reduced barriers to health care and frequent analysis and reporting of incidence data. Epidemic surveillance and control appear to be insufficiently timely in fragile states, and need to be strengthened. Greater reliance on formal and informal notifications is warranted. Outbreak reports should be more standardised and enable monitoring of surveillance systems' effectiveness. PMID:21861869
Fernandes, Anand M.; Balasegaram, Sooria; Willis, Caroline; Wimalarathna, Helen M. L.; Maiden, Martin C.; McCarthy, Noel D.
2015-01-01
Background. Cattle are the second most common source of human campylobacteriosis. However, routes to account for this scale of transmission have not been identified. In contrast to chicken, red meat is not heavily contaminated at point of sale. Although effective pasteurization prevents milk-borne infection, apparently sporadic infections may include undetected outbreaks from raw or perhaps incompletely pasteurized milk. Methods. A rise in Campylobacter gastroenteritis in an isolated population was investigated using whole-genome sequencing (WGS), an epidemiological study, and environmental investigations. Results. A single strain was identified in 20 cases, clearly distinguishable from other local strains and a reference population by WGS. A case-case analysis showed association of infection with the outbreak strain and milk from a single dairy (odds ratio, 8; Fisher exact test P value = .023). Despite temperature records indicating effective pasteurization, mechanical faults likely to lead to incomplete pasteurization of part of the milk were identified by further testing and examination of internal components of dairy equipment. Conclusions. Here, milk distribution concentrated on a small area, including school-aged children with low background incidence of campylobacteriosis, facilitated outbreak identification. Low-level contamination of widely distributed milk would not produce as detectable an outbreak signal. Such hidden outbreaks may contribute to the substantial burden of apparently sporadic Campylobacter from cattle where transmission routes are not certain. The effective discrimination of outbreak isolates from a reference population using WGS shows that integrating these data and approaches into surveillance could support the detection as well as investigation of such outbreaks. PMID:26063722
Jacobsen, Kathryn H; Aguirre, A Alonso; Bailey, Charles L; Baranova, Ancha V; Crooks, Andrew T; Croitoru, Arie; Delamater, Paul L; Gupta, Jhumka; Kehn-Hall, Kylene; Narayanan, Aarthi; Pierobon, Mariaelena; Rowan, Katherine E; Schwebach, J Reid; Seshaiyer, Padmanabhan; Sklarew, Dann M; Stefanidis, Anthony; Agouris, Peggy
2016-03-01
As the Ebola outbreak in West Africa wanes, it is time for the international scientific community to reflect on how to improve the detection of and coordinated response to future epidemics. Our interdisciplinary team identified key lessons learned from the Ebola outbreak that can be clustered into three areas: environmental conditions related to early warning systems, host characteristics related to public health, and agent issues that can be addressed through the laboratory sciences. In particular, we need to increase zoonotic surveillance activities, implement more effective ecological health interventions, expand prediction modeling, support medical and public health systems in order to improve local and international responses to epidemics, improve risk communication, better understand the role of social media in outbreak awareness and response, produce better diagnostic tools, create better therapeutic medications, and design better vaccines. This list highlights research priorities and policy actions the global community can take now to be better prepared for future emerging infectious disease outbreaks that threaten global public health and security.
Relevance of Global Health Security to the US Export Economy.
Cassell, Cynthia H; Bambery, Zoe; Roy, Kakoli; Meltzer, Martin I; Ahmed, Zara; Payne, Rebecca L; Bunnell, Rebecca E
To reduce the health security risk and impact of outbreaks around the world, the US Centers for Disease Control and Prevention and its partners are building capabilities to prevent, detect, and contain outbreaks in 49 global health security priority countries. We examine the extent of economic vulnerability to the US export economy posed by trade disruptions in these 49 countries. Using 2015 US Department of Commerce data, we assessed the value of US exports and the number of US jobs supported by those exports. US exports to the 49 countries exceeded $308 billion and supported more than 1.6 million jobs across all US states in agriculture, manufacturing, mining, oil and gas, services, and other sectors. These exports represented 13.7% of all US export revenue worldwide and 14.3% of all US jobs supported by all US exports. The economic linkages between the United States and these global health security priority countries illustrate the importance of ensuring that countries have the public health capacities needed to control outbreaks at their source before they become pandemics.
Relevance of Global Health Security to the US Export Economy
Cassell, Cynthia H.; Bambery, Zoe; Roy, Kakoli; Meltzer, Martin I.; Ahmed, Zara; Payne, Rebecca L.
2017-01-01
To reduce the health security risk and impact of outbreaks around the world, the US Centers for Disease Control and Prevention and its partners are building capabilities to prevent, detect, and contain outbreaks in 49 global health security priority countries. We examine the extent of economic vulnerability to the US export economy posed by trade disruptions in these 49 countries. Using 2015 US Department of Commerce data, we assessed the value of US exports and the number of US jobs supported by those exports. US exports to the 49 countries exceeded $308 billion and supported more than 1.6 million jobs across all US states in agriculture, manufacturing, mining, oil and gas, services, and other sectors. These exports represented 13.7% of all US export revenue worldwide and 14.3% of all US jobs supported by all US exports. The economic linkages between the United States and these global health security priority countries illustrate the importance of ensuring that countries have the public health capacities needed to control outbreaks at their source before they become pandemics. PMID:29199867
Dallman, T J; Byrne, L; Launders, N; Glen, K; Grant, K A; Jenkins, C
2015-06-01
Many serogroups of Shiga toxin-producing Escherichia coli (STEC) other than serogroup O157 (non-O157 STEC), for example STEC O26:H11, are highly pathogenic and capable of causing haemolytic uraemic syndrome. A recent increase in non-O157 STEC cases identified in England, resulting from a change in the testing paradigm, prompted a review of the current methods available for detection and typing of non-O157 STEC for surveillance and outbreak investigations. Nineteen STEC O26:H11 strains, including four from a nursery outbreak were selected to assess typing methods. Serotyping and multilocus sequence typing were not able to discriminate between the stx-producing strains in the dataset. However, genome sequencing provided rapid and robust confirmation that isolates of STEC O26:H11 associated with a nursery outbreak were linked at the molecular level, had a common source and were distinct from the other strains analysed. Virulence gene profiling of DNA extracted from a polymerase chain reaction (PCR)-positive/culture-negative faecal specimen from a case that was epidemiologically linked to the STEC O26:H11 nursery outbreak, provided evidence at the molecular level to support that link. During this study, we describe the utility of PCR and the genome sequencing approach in facilitating surveillance and enhancing the response to outbreaks of non-O157 STEC.
Layer, Franziska; Sanchini, Andrea; Strommenger, Birgit; Cuny, Christiane; Breier, Ann-Christin; Proquitté, Hans; Bührer, Christoph; Schenkel, Karl; Bätzing-Feigenbaum, Jörg; Greutelaers, Benedikt; Nübel, Ulrich; Gastmeier, Petra; Eckmanns, Tim; Werner, Guido
2015-10-01
Outbreaks of Staphylococcus aureus are common in neonatal intensive care units (NICUs). Usually they are documented for methicillin-resistant strains, while reports involving methicillin-susceptible S. aureus (MSSA) strains are rare. In this study we report the epidemiological and molecular investigation of an MSSA outbreak in a NICU among preterm neonates. Infection control measures and interventions were commissioned by the Local Public Health Authority and supported by the Robert Koch Institute. To support epidemiological investigations molecular typing was done by spa-typing and Multilocus sequence typing; the relatedness of collected isolates was further elucidated by DNA SmaI-macrorestriction, microarray analysis and bacterial whole genome sequencing. A total of 213 neonates, 123 healthcare workers and 205 neonate parents were analyzed in the period November 2011 to November 2012. The outbreak strain was characterized as a MSSA spa-type t021, able to produce toxic shock syndrome toxin-1 and Enterotoxin A. We identified seventeen neonates (of which two died from toxic shock syndrome), four healthcare workers and three parents putatively involved in the outbreak. Whole-genome sequencing permitted to exclude unrelated cases from the outbreak and to discuss the role of healthcare workers as a reservoir of S. aureus on the NICU. Genome comparisons also indicated the presence of the respective clone on the ward months before the first colonized/infected neonates were detected. Copyright © 2015 Elsevier GmbH. All rights reserved.
Bautista, Leonelo E; Herrera, Víctor M
2018-05-24
We evaluated whether outbreaks of Zika virus (ZIKV) infection, newborn microcephaly, and Guillain-Barré syndrome (GBS) in Latin America may be detected through current surveillance systems, and how cases detected through surveillance may increase health care burden. We estimated the sensitivity and specificity of surveillance case definitions using published data. We assumed a 10% ZIKV infection risk during a non-outbreak period and hypothetical increases in risk during an outbreak period. We used sensitivity and specificity estimates to correct for non-differential misclassification, and calculated a misclassification-corrected relative risk comparing both periods. To identify the smallest hypothetical increase in risk resulting in a detectable outbreak we compared the misclassification-corrected relative risk to the relative risk corresponding to the upper limit of the endemic channel (mean + 2 SD). We also estimated the proportion of false positive cases detected during the outbreak. We followed the same approach for microcephaly and GBS, but assumed the risk of ZIKV infection doubled during the outbreak, and ZIKV infection increased the risk of both diseases. ZIKV infection outbreaks were not detectable through non-serological surveillance. Outbreaks were detectable through serologic surveillance if infection risk increased by at least 10%, but more than 50% of all cases were false positive. Outbreaks of severe microcephaly were detected if ZIKV infection increased prevalence of this condition by at least 24.0 times. When ZIKV infection did not increase the prevalence of severe microcephaly, 34.7 to 82.5% of all cases were false positive, depending on diagnostic accuracy. GBS outbreaks were detected if ZIKV infection increased the GBS risk by at least seven times. For optimal GBS diagnosis accuracy, the proportion of false positive cases ranged from 29 to 54% and from 45 to 56% depending on the incidence of GBS mimics. Current surveillance systems have a low probability of detecting outbreaks of ZIKV infection, severe microcephaly, and GBS, and could result in significant increases in health care burden, due to the detection of large numbers of false positive cases. In view of these limitations, Latin American countries should consider alternative options for surveillance.
NASA Astrophysics Data System (ADS)
Tibbetts, Clark; Lichanska, Agnieszka M.; Borsuk, Lisa A.; Weslowski, Brian; Morris, Leah M.; Lorence, Matthew C.; Schafer, Klaus O.; Campos, Joseph; Sene, Mohamadou; Myers, Christopher A.; Faix, Dennis; Blair, Patrick J.; Brown, Jason; Metzgar, David
2010-04-01
High-density resequencing microarrays support simultaneous detection and identification of multiple viral and bacterial pathogens. Because detection and identification using RPM is based upon multiple specimen-specific target pathogen gene sequences generated in the individual test, the test results enable both a differential diagnostic analysis and epidemiological tracking of detected pathogen strains and variants from one specimen to the next. The RPM assay enables detection and identification of pathogen sequences that share as little as 80% sequence similarity to prototype target gene sequences represented as detector tiles on the array. This capability enables the RPM to detect and identify previously unknown strains and variants of a detected pathogen, as in sentinel cases associated with an infectious disease outbreak. We illustrate this capability using assay results from testing influenza A virus vaccines configured with strains that were first defined years after the design of the RPM microarray. Results are also presented from RPM-Flu testing of three specimens independently confirmed to the positive for the 2009 Novel H1N1 outbreak strain of influenza virus.
[Study of tuberculosis outbreaks reported in Catalonia, 1998-2002].
Bran, Carlos M; Caylá, Joan A; Domínguez, Angela; Camps, Neus; Godoy, Pere; Orcau, Angels; Barrabeig, Irene; Alcaide, José; Altet, Neus; Alvarez, Pep
2006-06-01
To analyze the characteristics of tuberculosis outbreaks declared under vigilance programs in Catalonia. Descriptive study of outbreaks from 1998 through 2002 for which reports were available. An outbreak was defined as 3 or more associated cases appearing within a year. For 2 health care regions, outbreaks for which there were full surveillance reports with contact tracing were compared to outbreaks identified but which had not been fully reported. Twenty-seven outbreaks were analyzed. Nineteen (70%) occurred within families. A total of 22 outbreaks were declared upon identification of the true index case and 5 upon detection of secondary cases. The mean annual incidence of outbreaks was 0.40/100,100 inhabitants. Most cases were in males 16 to 40 years of age and involved cavitary lesions and a clinically significant diagnostic delay. Twenty-seven outbreaks caused 69 secondary cases. A longer diagnostic delay was seen to correspond to a larger number of secondary cases (P=.08). In the 2 health care regions analyzed, full surveillance reports with contact tracing were issued for 2 of the 14 outbreaks detected (14.4%). Tuberculosis outbreaks are common but investigative follow-up is scarce. The size of the outbreak is related to the length of diagnostic delay. Rapid diagnosis, contact tracing, and the issuance of a public health report should be priorities in all outbreaks detected.
Fernandes, Anand M; Balasegaram, Sooria; Willis, Caroline; Wimalarathna, Helen M L; Maiden, Martin C; McCarthy, Noel D
2015-09-15
Cattle are the second most common source of human campylobacteriosis. However, routes to account for this scale of transmission have not been identified. In contrast to chicken, red meat is not heavily contaminated at point of sale. Although effective pasteurization prevents milk-borne infection, apparently sporadic infections may include undetected outbreaks from raw or perhaps incompletely pasteurized milk. A rise in Campylobacter gastroenteritis in an isolated population was investigated using whole-genome sequencing (WGS), an epidemiological study, and environmental investigations. A single strain was identified in 20 cases, clearly distinguishable from other local strains and a reference population by WGS. A case-case analysis showed association of infection with the outbreak strain and milk from a single dairy (odds ratio, 8; Fisher exact test P value = .023). Despite temperature records indicating effective pasteurization, mechanical faults likely to lead to incomplete pasteurization of part of the milk were identified by further testing and examination of internal components of dairy equipment. Here, milk distribution concentrated on a small area, including school-aged children with low background incidence of campylobacteriosis, facilitated outbreak identification. Low-level contamination of widely distributed milk would not produce as detectable an outbreak signal. Such hidden outbreaks may contribute to the substantial burden of apparently sporadic Campylobacter from cattle where transmission routes are not certain. The effective discrimination of outbreak isolates from a reference population using WGS shows that integrating these data and approaches into surveillance could support the detection as well as investigation of such outbreaks. © The Author 2015. Published by Oxford University Press on behalf of the Infectious Diseases Society of America.
A Bayesian system to detect and characterize overlapping outbreaks.
Aronis, John M; Millett, Nicholas E; Wagner, Michael M; Tsui, Fuchiang; Ye, Ye; Ferraro, Jeffrey P; Haug, Peter J; Gesteland, Per H; Cooper, Gregory F
2017-09-01
Outbreaks of infectious diseases such as influenza are a significant threat to human health. Because there are different strains of influenza which can cause independent outbreaks, and influenza can affect demographic groups at different rates and times, there is a need to recognize and characterize multiple outbreaks of influenza. This paper describes a Bayesian system that uses data from emergency department patient care reports to create epidemiological models of overlapping outbreaks of influenza. Clinical findings are extracted from patient care reports using natural language processing. These findings are analyzed by a case detection system to create disease likelihoods that are passed to a multiple outbreak detection system. We evaluated the system using real and simulated outbreaks. The results show that this approach can recognize and characterize overlapping outbreaks of influenza. We describe several extensions that appear promising. Copyright © 2017 Elsevier Inc. All rights reserved.
2013-01-01
Background The increasing frequency and intensity of dengue outbreaks in endemic and non-endemic countries requires a rational, evidence based response. To this end, we aimed to collate the experiences of a number of affected countries, identify strengths and limitations in dengue surveillance, outbreak preparedness, detection and response and contribute towards the development of a model contingency plan adaptable to country needs. Methods The study was undertaken in five Latin American (Brazil, Colombia, Dominican Republic, Mexico, Peru) and five in Asian countries (Indonesia, Malaysia, Maldives, Sri Lanka, Vietnam). A mixed-methods approach was used which included document analysis, key informant interviews, focus-group discussions, secondary data analysis and consensus building by an international dengue expert meeting organised by the World Health Organization, Special Program for Research and Training in Tropical Diseases (WHO-TDR). Results Country information on dengue is based on compulsory notification and reporting (“passive surveillance”), with laboratory confirmation (in all participating Latin American countries and some Asian countries) or by using a clinical syndromic definition. Seven countries additionally had sentinel sites with active dengue reporting, some also had virological surveillance. Six had agreed a formal definition of a dengue outbreak separate to seasonal variation in case numbers. Countries collected data on a range of warning signs that may identify outbreaks early, but none had developed a systematic approach to identifying and responding to the early stages of an outbreak. Outbreak response plans varied in quality, particularly regarding the early response. The surge capacity of hospitals with recent dengue outbreaks varied; those that could mobilise additional staff, beds, laboratory support and resources coped best in comparison to those improvising a coping strategy during the outbreak. Hospital outbreak management plans were present in 9/22 participating hospitals in Latin-America and 8/20 participating hospitals in Asia. Conclusions Considerable variation between countries was observed with regard to surveillance, outbreak detection, and response. Through discussion at the expert meeting, suggestions were made for the development of a more standardised approach in the form of a model contingency plan, with agreed outbreak definitions and country-specific risk assessment schemes to initiate early response activities according to the outbreak phase. This would also allow greater cross-country sharing of ideas. PMID:23800243
Badurdeen, Shiraz; Valladares, David Benitez; Farrar, Jeremy; Gozzer, Ernesto; Kroeger, Axel; Kuswara, Novia; Ranzinger, Silvia Runge; Tinh, Hien Tran; Leite, Priscila; Mahendradhata, Yodi; Skewes, Ronald; Verrall, Ayesha
2013-06-24
The increasing frequency and intensity of dengue outbreaks in endemic and non-endemic countries requires a rational, evidence based response. To this end, we aimed to collate the experiences of a number of affected countries, identify strengths and limitations in dengue surveillance, outbreak preparedness, detection and response and contribute towards the development of a model contingency plan adaptable to country needs. The study was undertaken in five Latin American (Brazil, Colombia, Dominican Republic, Mexico, Peru) and five in Asian countries (Indonesia, Malaysia, Maldives, Sri Lanka, Vietnam). A mixed-methods approach was used which included document analysis, key informant interviews, focus-group discussions, secondary data analysis and consensus building by an international dengue expert meeting organised by the World Health Organization, Special Program for Research and Training in Tropical Diseases (WHO-TDR). Country information on dengue is based on compulsory notification and reporting ("passive surveillance"), with laboratory confirmation (in all participating Latin American countries and some Asian countries) or by using a clinical syndromic definition. Seven countries additionally had sentinel sites with active dengue reporting, some also had virological surveillance. Six had agreed a formal definition of a dengue outbreak separate to seasonal variation in case numbers. Countries collected data on a range of warning signs that may identify outbreaks early, but none had developed a systematic approach to identifying and responding to the early stages of an outbreak. Outbreak response plans varied in quality, particularly regarding the early response. The surge capacity of hospitals with recent dengue outbreaks varied; those that could mobilise additional staff, beds, laboratory support and resources coped best in comparison to those improvising a coping strategy during the outbreak. Hospital outbreak management plans were present in 9/22 participating hospitals in Latin-America and 8/20 participating hospitals in Asia. Considerable variation between countries was observed with regard to surveillance, outbreak detection, and response. Through discussion at the expert meeting, suggestions were made for the development of a more standardised approach in the form of a model contingency plan, with agreed outbreak definitions and country-specific risk assessment schemes to initiate early response activities according to the outbreak phase. This would also allow greater cross-country sharing of ideas.
Shen, Yanna; Cooper, Gregory F
2012-09-01
This paper investigates Bayesian modeling of known and unknown causes of events in the context of disease-outbreak detection. We introduce a multivariate Bayesian approach that models multiple evidential features of every person in the population. This approach models and detects (1) known diseases (e.g., influenza and anthrax) by using informative prior probabilities and (2) unknown diseases (e.g., a new, highly contagious respiratory virus that has never been seen before) by using relatively non-informative prior probabilities. We report the results of simulation experiments which support that this modeling method can improve the detection of new disease outbreaks in a population. A contribution of this paper is that it introduces a multivariate Bayesian approach for jointly modeling both known and unknown causes of events. Such modeling has general applicability in domains where the space of known causes is incomplete. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.
Rapid Field Response to a Cluster of Illnesses and Deaths - Sinoe County, Liberia, April-May, 2017.
Doedeh, John; Frimpong, Joseph Asamoah; Yealue, Kwuakuan D M; Wilson, Himiede W; Konway, Youhn; Wiah, Samson Q; Doedeh, Vivian; Bao, Umaru; Seneh, George; Gorwor, Lawrence; Toe, Sylvester; Ghartey, Emmanuel; Larway, Lawrence; Gweh, Dedesco; Gonotee, Philemon; Paasewe, Thomas; Tamatai, George; Yarkeh, James; Smith, Samuel; Brima-Davis, Annette; Dauda, George; Monger, Thomas; Gornor-Pewu, Leleh W; Lombeh, Siafa; Naiene, Jeremias; Dovillie, Nathaniel; Korvayan, Mark; George, Geraldine; Kerwillain, Garrison; Jetoh, Ralph; Friesen, Suzanne; Kinkade, Carl; Katawera, Victoria; Amo-Addae, Maame; George, Roseline N; Gbanya, Miatta Z; Dokubo, E Kainne
2017-10-27
On April 25, 2017, the Sinoe County Health Team (CHT) notified the Liberia Ministry of Health (MoH) and the National Public Health Institute of Liberia of an unknown illness among 14 persons that resulted in eight deaths in Sinoe County. On April 26, the National Rapid Response Team and epidemiologists from CDC, the World Health Organization (WHO) and the African Field Epidemiology Network (AFENET) in Liberia were deployed to support the county-led response. Measures were immediately implemented to identify all cases, ascertain the cause of illness, and control the outbreak. Illness was associated with attendance at a funeral event, and laboratory testing confirmed Neisseria meningitidis in biologic specimens from cases. The 2014-2015 Ebola virus disease (Ebola) outbreak in West Africa devastated Liberia's already fragile health system, and it took many months for the country to mount an effective response to control the outbreak. Substantial efforts have been made to strengthen Liberia's health system to prevent, detect, and respond to health threats. The rapid and efficient field response to this outbreak of N. meningitidis resulted in implementation of appropriate steps to prevent a widespread outbreak and reflects improved public health and outbreak response capacity in Liberia.
Kirian, Michelle L; Weintraub, June M
2010-07-20
Water utilities continue to be interested in implementing syndromic surveillance for the enhanced detection of waterborne disease outbreaks. The authors evaluated the ability of sales of over-the-counter diarrheal remedies available from the National Retail Data Monitor to predict endemic and epidemic gastrointestinal disease in the San Francisco Bay Area. Time series models were fit to weekly diarrheal remedy sales and diarrheal illness case counts. Cross-correlations between the pre-whitened residual series were calculated. Diarrheal remedy sales model residuals were regressed on the number of weekly outbreaks and outbreak-associated cases. Diarrheal remedy sales models were used to auto-forecast one week-ahead sales. The sensitivity and specificity of signals, generated by observed diarrheal remedy sales exceeding the upper 95% forecast confidence interval, in predicting weekly outbreaks were calculated. No significant correlations were identified between weekly diarrheal remedy sales and diarrhea illness case counts, outbreak counts, or the number of outbreak-associated cases. Signals generated by forecasting with the diarrheal remedy sales model did not coincide with outbreak weeks more reliably than signals chosen randomly. This work does not support the implementation of syndromic surveillance for gastrointestinal disease with data available though the National Retail Data Monitor.
Colón-González, Felipe J; Lake, Iain R; Morbey, Roger A; Elliot, Alex J; Pebody, Richard; Smith, Gillian E
2018-04-24
Syndromic surveillance complements traditional public health surveillance by collecting and analysing health indicators in near real time. The rationale of syndromic surveillance is that it may detect health threats faster than traditional surveillance systems permitting more timely, and hence potentially more effective public health action. The effectiveness of syndromic surveillance largely relies on the methods used to detect aberrations. Very few studies have evaluated the performance of syndromic surveillance systems and consequently little is known about the types of events that such systems can and cannot detect. We introduce a framework for the evaluation of syndromic surveillance systems that can be used in any setting based upon the use of simulated scenarios. For a range of scenarios this allows the time and probability of detection to be determined and uncertainty is fully incorporated. In addition, we demonstrate how such a framework can model the benefits of increases in the number of centres reporting syndromic data and also determine the minimum size of outbreaks that can or cannot be detected. Here, we demonstrate its utility using simulations of national influenza outbreaks and localised outbreaks of cryptosporidiosis. Influenza outbreaks are consistently detected with larger outbreaks being detected in a more timely manner. Small cryptosporidiosis outbreaks (<1000 symptomatic individuals) are unlikely to be detected. We also demonstrate the advantages of having multiple syndromic data streams (e.g. emergency attendance data, telephone helpline data, general practice consultation data) as different streams are able to detect different outbreak types with different efficacy (e.g. emergency attendance data are useful for the detection of pandemic influenza but not for outbreaks of cryptosporidiosis). We also highlight that for any one disease, the utility of data streams may vary geographically, and that the detection ability of syndromic surveillance varies seasonally (e.g. an influenza outbreak starting in July is detected sooner than one starting later in the year). We argue that our framework constitutes a useful tool for public health emergency preparedness in multiple settings. The proposed framework allows the exhaustive evaluation of any syndromic surveillance system and constitutes a useful tool for emergency preparedness and response.
Rota, J S; Turner, J C; Yost-Daljev, M K; Freeman, M; Toney, D M; Meisel, E; Williams, N; Sowers, S B; Lowe, L; Rota, P A; Nicolai, L A; Peake, L; Bellini, W J
2009-10-01
Following the clinical diagnosis of the first case of mumps on September 22, 2006 at the University of Virginia (UVA), 52 suspected cases were identified through active surveillance for mumps by the end of December 2006. Samples were collected from 47 students who presented with parotitis despite a documented history of two doses of measles, mumps, and rubella (MMR) vaccine. Six of 47 serum samples (13%) were positive for mumps IgM, and 46/47 specimens were positive for mumps IgG. Endpoint titration of acute phase serum samples from laboratory-confirmed cases did not provide evidence that elevated serum IgG is a consistent marker for infection among cases due to secondary vaccine failure. Buccal swab samples from 39 of the 47 students were tested by real-time reverse transcription-polymerase chain reaction (RT-PCR) and/or viral culture. Mumps virus or mumps RNA was detected in 12 of 39 buccal samples (31%). Genetic analysis of the virus from the outbreak at UVA indicated that the outbreak was not linked to the large mumps outbreak in the Midwestern US that occurred earlier in 2006. Our findings support the use of viral detection to improve laboratory diagnosis of mumps among persons who have received two doses of MMR.
Buliva, Evans; Elhakim, Mohamed; Tran Minh, Nhu Nguyen; Elkholy, Amgad; Mala, Peter; Abubakar, Abdinasir; Malik, Sk Md Mamunur Rahman
2017-01-01
The Eastern Mediterranean Region (EMR) of the World Health Organization (WHO) continues to be a hotspot for emerging and reemerging infectious diseases and the need to prevent, detect, and respond to any infectious diseases that pose a threat to global health security remains a priority. Many risk factors contribute in the emergence and rapid spread of epidemic diseases in the Region including acute and protracted humanitarian emergencies, resulting in fragile health systems, increased population mobility, rapid urbanization, climate change, weak surveillance and limited laboratory diagnostic capacity, and increased human-animal interaction. In EMR, several infectious disease outbreaks were detected, investigated, and rapidly contained over the past 5 years including: yellow fever in Sudan, Middle East respiratory syndrome in Bahrain, Oman, Qatar, Saudi Arabia, United Arab Emirates, and Yemen, cholera in Iraq, avian influenza A (H5N1) infection in Egypt, and dengue fever in Yemen, Sudan, and Pakistan. Dengue fever remains an important public health concern, with at least eight countries in the region being endemic for the disease. The emergence of MERS-CoV in the region in 2012 and its continued transmission currently poses one of the greatest threats. In response to the growing frequency, duration, and scale of disease outbreaks, WHO has worked closely with member states in the areas of improving public health preparedness, surveillance systems, outbreak response, and addressing critical knowledge gaps. A Regional network for experts and technical institutions has been established to facilitate support for international outbreak response. Major challenges are faced as a result of protracted humanitarian crises in the region. Funding gaps, lack of integrated approaches, weak surveillance systems, and absence of comprehensive response plans are other areas of concern. Accelerated efforts are needed by Regional countries, with the continuous support of WHO, to build and maintain a resilient public health system for detection and response to all acute public health events.
Buliva, Evans; Elhakim, Mohamed; Tran Minh, Nhu Nguyen; Elkholy, Amgad; Mala, Peter; Abubakar, Abdinasir; Malik, Sk Md Mamunur Rahman
2017-01-01
The Eastern Mediterranean Region (EMR) of the World Health Organization (WHO) continues to be a hotspot for emerging and reemerging infectious diseases and the need to prevent, detect, and respond to any infectious diseases that pose a threat to global health security remains a priority. Many risk factors contribute in the emergence and rapid spread of epidemic diseases in the Region including acute and protracted humanitarian emergencies, resulting in fragile health systems, increased population mobility, rapid urbanization, climate change, weak surveillance and limited laboratory diagnostic capacity, and increased human–animal interaction. In EMR, several infectious disease outbreaks were detected, investigated, and rapidly contained over the past 5 years including: yellow fever in Sudan, Middle East respiratory syndrome in Bahrain, Oman, Qatar, Saudi Arabia, United Arab Emirates, and Yemen, cholera in Iraq, avian influenza A (H5N1) infection in Egypt, and dengue fever in Yemen, Sudan, and Pakistan. Dengue fever remains an important public health concern, with at least eight countries in the region being endemic for the disease. The emergence of MERS-CoV in the region in 2012 and its continued transmission currently poses one of the greatest threats. In response to the growing frequency, duration, and scale of disease outbreaks, WHO has worked closely with member states in the areas of improving public health preparedness, surveillance systems, outbreak response, and addressing critical knowledge gaps. A Regional network for experts and technical institutions has been established to facilitate support for international outbreak response. Major challenges are faced as a result of protracted humanitarian crises in the region. Funding gaps, lack of integrated approaches, weak surveillance systems, and absence of comprehensive response plans are other areas of concern. Accelerated efforts are needed by Regional countries, with the continuous support of WHO, to build and maintain a resilient public health system for detection and response to all acute public health events. PMID:29098145
Boxman, Ingeborg L A; Dijkman, Remco; te Loeke, Nathalie A J M; Hägele, Geke; Tilburg, Jeroen J H C; Vennema, Harry; Koopmans, Marion
2009-01-01
In this study, we investigated whether environmental swabs can be used to demonstrate the presence of norovirus in outbreak settings. First, a procedure was set up based on viral RNA extraction using guanidium isothiocyanate buffer and binding of nucleic acids to silica. Subsequently, environmental swabs were taken at 23 Dutch restaurants and four cruise ships involved in outbreaks of gastroenteritis. Outbreaks were selected based on clinical symptoms consistent with viral gastroenteritis and time between consumption of suspected food and onset of clinical symptoms (>12 h). Norovirus RNA was demonstrated by real-time reverse transcriptase PCR in 51 of 86 (59%) clinical specimens from 12 of 14 outbreaks (86%), in 13 of 90 (14%) food specimens from 4 of 18 outbreaks (22%), and in 48 of 119 (40%) swab specimens taken from 14 of 27 outbreaks (52%). Positive swab samples agreed with positive clinical samples in seven outbreaks, showing identical sequences. Furthermore, norovirus was detected on swabs taken from kitchen and bathroom surfaces in five outbreaks in which no clinical samples were collected and two outbreaks with negative fecal samples. The detection rate was highest for outbreaks associated with catered meals and lowest for restaurant-associated outbreaks. The use of environmental swabs may be a useful tool in addition to testing of food and clinical specimens, particularlywhen viral RNA is detected on surfaces used for food preparation.
Automated biosurveillance data from England and Wales, 1991-2011.
Enki, Doyo G; Noufaily, Angela; Garthwaite, Paul H; Andrews, Nick J; Charlett, André; Lane, Chris; Farrington, C Paddy
2013-01-01
Outbreak detection systems for use with very large multiple surveillance databases must be suited both to the data available and to the requirements of full automation. To inform the development of more effective outbreak detection algorithms, we analyzed 20 years of data (1991-2011) from a large laboratory surveillance database used for outbreak detection in England and Wales. The data relate to 3,303 distinct types of infectious pathogens, with a frequency range spanning 6 orders of magnitude. Several hundred organism types were reported each week. We describe the diversity of seasonal patterns, trends, artifacts, and extra-Poisson variability to which an effective multiple laboratory-based outbreak detection system must adjust. We provide empirical information to guide the selection of simple statistical models for automated surveillance of multiple organisms, in the light of the key requirements of such outbreak detection systems, namely, robustness, flexibility, and sensitivity.
Automated Biosurveillance Data from England and Wales, 1991–2011
Enki, Doyo G.; Noufaily, Angela; Garthwaite, Paul H.; Andrews, Nick J.; Charlett, André; Lane, Chris
2013-01-01
Outbreak detection systems for use with very large multiple surveillance databases must be suited both to the data available and to the requirements of full automation. To inform the development of more effective outbreak detection algorithms, we analyzed 20 years of data (1991–2011) from a large laboratory surveillance database used for outbreak detection in England and Wales. The data relate to 3,303 distinct types of infectious pathogens, with a frequency range spanning 6 orders of magnitude. Several hundred organism types were reported each week. We describe the diversity of seasonal patterns, trends, artifacts, and extra-Poisson variability to which an effective multiple laboratory-based outbreak detection system must adjust. We provide empirical information to guide the selection of simple statistical models for automated surveillance of multiple organisms, in the light of the key requirements of such outbreak detection systems, namely, robustness, flexibility, and sensitivity. PMID:23260848
Osemek, Paweł; Kocik, Janusz; Paśnik, Krzysztof
2009-12-01
This article provides a short review about trends of developing current syndromic surveillance systems. To improve methods of early detection of natural or bioterrorism-related outbreaks, it has to be established a new way of epidemiological thinking, which uses innovative real-time surveillance systems. Syndromic surveillance has been created for an early detection, to monitor the temporo-spatial spread of an outbreak, and to provide prompt data for immediate analysis and feedback to public health authorities. It supports timely decision making process for countermeasure procedures. Framework of syndromic surveillance system requires a proper electronic infrastructure to be build up. Optimal syndrome definitions and data sources for continuing specific diseases outbreak surveillance have not been determined so far. Systems of interest might enhance collaboration among clinical providers, primary care providers, emergency services, information-systems professionals and public health agencies. However economic scope of this undertakings effectively limits ability to implement it in Polish public health service right now. Besides, syndromic surveillance cannot replace traditional public health surveillance with a post-factum epidemiological investigation and laboratory analysis. It can be a useful supplement.
The Role of Public Knowledge, Resources, and Innovation in Responding to the Ebola Outbreak.
Goldstone, Brian J; Brown, Brandon
2015-10-01
Since the beginning of the recent Ebola outbreak, a sense of fear has developed among the public due to the novelty of our exposure to the virus and the ill-equipped nature of our health care systems. Media sensationalism, coupled with improper knowledge of Ebola, may have contributed to mass hysteria. Most support to tackle Ebola has been direct monetary aid. However, others are working on innovative methods to control the epidemic, including the development of rapid detection methods, experimental treatments, and a viable vaccine. Rapid screening and vaccine ideas are promising, but it is unlikely that they will be ready in the coming months. This raises the question of what other tools and technological innovation can be developed to effectively stem the spread of the outbreak. Although we hope the continued outpouring of aid and health care workers to West Africa will greatly reduce the impact of Ebola, communication, screenings, treatment, and vaccine are of central importance to stop this outbreak.
Ulleryd, Peter; Hugosson, Anna; Allestam, Görel; Bernander, Sverker; Claesson, Berndt E B; Eilertz, Ingrid; Hagaeus, Anne-Christine; Hjorth, Martin; Johansson, Agneta; de Jong, Birgitta; Lindqvist, Anna; Nolskog, Peter; Svensson, Nils
2012-11-21
An outbreak of Legionnaires' Disease took place in the Swedish town Lidköping on Lake Vänern in August 2004 and the number of pneumonia cases at the local hospital increased markedly. As soon as the first patients were diagnosed, health care providers were informed and an outbreak investigation was launched. Classical epidemiological investigation, diagnostic tests, environmental analyses, epidemiological typing and meteorological methods. Thirty-two cases were found. The median age was 62 years (range 36 - 88) and 22 (69%) were males. No common indoor exposure was found. Legionella pneumophila serogroup 1 was found at two industries, each with two cooling towers. In one cooling tower exceptionally high concentrations, 1.2 × 109 cfu/L, were found. Smaller amounts were also found in the other tower of the first industry and in one tower of the second plant. Sero- and genotyping of isolated L. pneumophila serogroup 1 from three patients and epidemiologically suspected environmental strains supported the cooling tower with the high concentration as the source. In all, two L. pneumophila strains were isolated from three culture confirmed cases and both these strains were detected in the cooling tower, but one strain in another cooling tower as well. Meteorological modelling demonstrated probable spread from the most suspected cooling tower towards the town centre and the precise location of four cases that were stray visitors to Lidköping. Classical epidemiological, environmental and microbiological investigation of an LD outbreak can be supported by meteorological modelling methods.The broad competence and cooperation capabilities in the investigation team from different authorities were of paramount importance in stopping this outbreak.
2012-01-01
Background An outbreak of Legionnaires’ Disease took place in the Swedish town Lidköping on Lake Vänern in August 2004 and the number of pneumonia cases at the local hospital increased markedly. As soon as the first patients were diagnosed, health care providers were informed and an outbreak investigation was launched. Methods Classical epidemiological investigation, diagnostic tests, environmental analyses, epidemiological typing and meteorological methods. Results Thirty-two cases were found. The median age was 62 years (range 36 – 88) and 22 (69%) were males. No common indoor exposure was found. Legionella pneumophila serogroup 1 was found at two industries, each with two cooling towers. In one cooling tower exceptionally high concentrations, 1.2 × 109 cfu/L, were found. Smaller amounts were also found in the other tower of the first industry and in one tower of the second plant. Sero- and genotyping of isolated L. pneumophila serogroup 1 from three patients and epidemiologically suspected environmental strains supported the cooling tower with the high concentration as the source. In all, two L. pneumophila strains were isolated from three culture confirmed cases and both these strains were detected in the cooling tower, but one strain in another cooling tower as well. Meteorological modelling demonstrated probable spread from the most suspected cooling tower towards the town centre and the precise location of four cases that were stray visitors to Lidköping. Conclusions Classical epidemiological, environmental and microbiological investigation of an LD outbreak can be supported by meteorological modelling methods. The broad competence and cooperation capabilities in the investigation team from different authorities were of paramount importance in stopping this outbreak. PMID:23171054
The History of Epidemic Typhus.
Angelakis, Emmanouil; Bechah, Yassina; Raoult, Didier
2016-08-01
Epidemic typhus caused by Rickettsia prowazekii is one of the oldest pestilential diseases of humankind. The disease is transmitted to human beings by the body louse Pediculus humanus corporis and is still considered a major threat by public health authorities, despite the efficacy of antibiotics, because poor sanitary conditions are conducive to louse proliferation. Epidemic typhus has accompanied disasters that impact humanity and has arguably determined the outcome of more wars than have soldiers and generals. The detection, identification, and characterization of microorganisms in ancient remains by paleomicrobiology has permitted the diagnosis of past epidemic typhus outbreaks through the detection of R. prowazekii. Various techniques, including microscopy and immunodetection, can be used in paleomicrobiology, but most of the data have been obtained by using PCR-based molecular techniques on dental pulp samples. Paleomicrobiology enabled the identification of the first outbreak of epidemic typhus in the 18th century in the context of a pan-European great war in the city of Douai, France, and supported the hypothesis that typhus was imported into Europe by Spanish soldiers returning from America. R. prowazekii was also detected in the remains of soldiers of Napoleon's Grand Army in Vilnius, Lithuania, which indicates that Napoleon's soldiers had epidemic typhus. The purpose of this article is to underscore the modern comprehension of clinical epidemic typhus, focus on the historical relationships of the disease, and examine the use of paleomicrobiology in the detection of past epidemic typhus outbreaks.
Category-Specific Comparison of Univariate Alerting Methods for Biosurveillance Decision Support
Elbert, Yevgeniy; Hung, Vivian; Burkom, Howard
2013-01-01
Objective For a multi-source decision support application, we sought to match univariate alerting algorithms to surveillance data types to optimize detection performance. Introduction Temporal alerting algorithms commonly used in syndromic surveillance systems are often adjusted for data features such as cyclic behavior but are subject to overfitting or misspecification errors when applied indiscriminately. In a project for the Armed Forces Health Surveillance Center to enable multivariate decision support, we obtained 4.5 years of out-patient, prescription and laboratory test records from all US military treatment facilities. A proof-of-concept project phase produced 16 events with multiple evidence corroboration for comparison of alerting algorithms for detection performance. We used the representative streams from each data source to compare sensitivity of 6 algorithms to injected spikes, and we used all data streams from 16 known events to compare them for detection timeliness. Methods The six methods compared were: Holt-Winters generalized exponential smoothing method (1)automated choice between daily methods, regression and an exponential weighted moving average (2)adaptive daily Shewhart-type chartadaptive one-sided daily CUSUMEWMA applied to 7-day means with a trend correction; and7-day temporal scan statistic Sensitivity testing: We conducted comparative sensitivity testing for categories of time series with similar scales and seasonal behavior. We added multiples of the standard deviation of each time series as single-day injects in separate algorithm runs. For each candidate method, we then used as a sensitivity measure the proportion of these runs for which the output of each algorithm was below alerting thresholds estimated empirically for each algorithm using simulated data streams. We identified the algorithm(s) whose sensitivity was most consistently high for each data category. For each syndromic query applied to each data source (outpatient, lab test orders, and prescriptions), 502 authentic time series were derived, one for each reporting treatment facility. Data categories were selected in order to group time series with similar expected algorithm performance: Median > 100 < Median ≤ 10Median = 0Lag 7 Autocorrelation Coefficient ≥ 0.2Lag 7 Autocorrelation Coefficient < 0.2 Timeliness testing: For the timeliness testing, we avoided artificiality of simulated signals by measuring alerting detection delays in the 16 corroborated outbreaks. The multiple time series from these events gave a total of 141 time series with outbreak intervals for timeliness testing. The following measures were computed to quantify timeliness of detection: Median Detection Delay – median number of days to detect the outbreak.Penalized Mean Detection Delay –mean number of days to detect the outbreak with outbreak misses penalized as 1 day plus the maximum detection time. Results Based on the injection results, the Holt-Winters algorithm was most sensitive among time series with positive medians. The adaptive CUSUM and the Shewhart methods were most sensitive for data streams with median zero. Table 1 provides timeliness results using the 141 outbreak-associated streams on sparse (Median=0) and non-sparse data categories. [Insert table #1 here] Data median Detection Delay, days Holt-winters Regression EWMA Adaptive Shewhart Adaptive CUSUM 7-day Trend-adj. EWMA 7-day Temporal Scan Median 0 Median 3 2 4 2 4.5 2 Penalized Mean 7.2 7 6.6 6.2 7.3 7.6 Median >0 Median 2 2 2.5 2 6 4 Penalized Mean 6.1 7 7.2 7.1 7.7 6.6 The gray shading in the table 1 indicates methods with shortest detection delays for sparse and non-sparse data streams. The Holt-Winters method was again superior for non-sparse data. For data with median=0, the adaptive CUSUM was superior for a daily false alarm probability of 0.01, but the Shewhart method was timelier for more liberal thresholds. Conclusions Both kinds of detection performance analysis showed the method based on Holt-Winters exponential smoothing superior on non-sparse time series with day-of-week effects. The adaptive CUSUM and She-whart methods proved optimal on sparse data and data without weekly patterns.
Levin-Rector, Alison; Nivin, Beth; Yeung, Alice; Fine, Annie D; Greene, Sharon K
2015-08-01
Timely outbreak detection is necessary to successfully control influenza in long-term care facilities (LTCFs) and other institutions. To supplement nosocomial outbreak reports, calls from infection control staff, and active laboratory surveillance, the New York City (NYC) Department of Health and Mental Hygiene implemented an automated building-level analysis to proactively identify LTCFs with laboratory-confirmed influenza activity. Geocoded addresses of LTCFs in NYC were compared with geocoded residential addresses for all case-patients with laboratory-confirmed influenza reported through passive surveillance. An automated daily analysis used the geocoded building identification number, approximate text matching, and key-word searches to identify influenza in residents of LTCFs for review and follow-up by surveillance coordinators. Our aim was to determine whether the building analysis improved prospective outbreak detection during the 2013-2014 influenza season. Of 119 outbreaks identified in LTCFs, 109 (92%) were ever detected by the building analysis, and 55 (46%) were first detected by the building analysis. Of the 5,953 LTCF staff and residents who received antiviral prophylaxis during the 2013-2014 season, 929 (16%) were at LTCFs where outbreaks were initially detected by the building analysis. A novel building-level analysis improved influenza outbreak identification in LTCFs in NYC, prompting timely infection control measures. Copyright © 2015 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.
Review of syndromic surveillance: implications for waterborne disease detection
Berger, Magdalena; Shiau, Rita; Weintraub, June M
2006-01-01
Syndromic surveillance is the gathering of data for public health purposes before laboratory or clinically confirmed information is available. Interest in syndromic surveillance has increased because of concerns about bioterrorism. In addition to bioterrorism detection, syndromic surveillance may be suited to detecting waterborne disease outbreaks. Theoretical benefits of syndromic surveillance include potential timeliness, increased response capacity, ability to establish baseline disease burdens, and ability to delineate the geographical reach of an outbreak. This review summarises the evidence gathered from retrospective, prospective, and simulation studies to assess the efficacy of syndromic surveillance for waterborne disease detection. There is little evidence that syndromic surveillance mitigates the effects of disease outbreaks through earlier detection and response. Syndromic surveillance should not be implemented at the expense of traditional disease surveillance, and should not be relied upon as a principal outbreak detection tool. The utility of syndromic surveillance is dependent on alarm thresholds that can be evaluated in practice. Syndromic data sources such as over the counter drug sales for detection of waterborne outbreaks should be further evaluated. PMID:16698988
Marshall, J A; Yuen, L K; Catton, M G; Gunesekere, I C; Wright, P J; Bettelheim, K A; Griffith, J M; Lightfoot, D; Hogg, G G; Gregory, J; Wilby, R; Gaston, J
2001-02-01
The role of diverse infectious agents, particularly Norwalk-like viruses (NLV), in three successive gastro-enteritis outbreaks in one setting (a restaurant) was evaluated. Methods included standard bacteriological tests, specific tests for Escherichia coli, tests for verocytotoxins, electron microscopy (EM) for viruses and reverse transcription-PCR (RT-PCR) methodology for NLV. No pathogenic bacteria were detected. Verocytotoxin genes, although detected by PCR in the first outbreak, could not be confirmed in the E. coli isolated, so they did not appear to be of significance. NLV was the main agent detected in each of the three outbreaks. DNA sequencing and phylogenetic analysis of the amplified products obtained from the RT-PCR positive specimens indicated that only one NLV strain was involved in each outbreak, but the NLV strains responsible for the three outbreaks were different from each other. PCR technology for detection of NLV proved highly sensitive, but failed to detect one specimen which was positive by EM. The restaurant associated with the outbreaks is a Mediterranean-style restaurant where food from a common platter is typically eaten with fingers. The findings indicate that NLV was introduced by guests or staff and was not due to a long-term reservoir within the setting.
Strategies for Early Outbreak Detection of Malaria in the Amhara Region of Ethiopia
NASA Astrophysics Data System (ADS)
Nekorchuk, D.; Gebrehiwot, T.; Mihretie, A.; Awoke, W.; Wimberly, M. C.
2017-12-01
Traditional epidemiological approaches to early detection of disease outbreaks are based on relatively straightforward thresholds (e.g. 75th percentile, standard deviations) estimated from historical case data. For diseases with strong seasonality, these can be modified to create separate thresholds for each seasonal time step. However, for disease processes that are non-stationary, more sophisticated techniques are needed to more accurately estimate outbreak threshold values. Early detection for geohealth-related diseases that also have environmental drivers, such as vector-borne diseases, may also benefit from the integration of time-lagged environmental data and disease ecology models into the threshold calculations. The Epidemic Prognosis Incorporating Disease and Environmental Monitoring for Integrated Assessment (EPIDEMIA) project has been integrating malaria case surveillance with remotely-sensed environmental data for early detection, warning, and forecasting of malaria epidemics in the Amhara region of Ethiopia, and has five years of weekly time series data from 47 woredas (districts). Efforts to reduce the burden of malaria in Ethiopia has been met with some notable success in the past two decades with major reduction in cases and deaths. However, malaria remains a significant public health threat as 60% of the population live in malarious areas, and due to the seasonal and unstable transmission patterns with cyclic outbreaks, protective immunity is generally low which could cause high morbidity and mortality during the epidemics. This study compared several approaches for defining outbreak thresholds and for identifying a potential outbreak based on deviations from these thresholds. We found that model-based approaches that accounted for climate-driven seasonality in malaria transmission were most effective, and that incorporating a trend component improved outbreak detection in areas with active malaria elimination efforts. An advantage of these early detection techniques is that they can detect climate-driven outbreaks as well as outbreaks driven by social factors such as human migration.
Xu, Wenti; Chen, Tianmu; Dong, Xiaochun; Kong, Mei; Lv, Xiuzhi; Li, Lin
2017-01-01
School-based influenza-like-illness (ILI) syndromic surveillance can be an important part of influenza community surveillance by providing early warnings for outbreaks and leading to a fast response. From September 2012 to December 2014, syndromic surveillance of ILI was carried out in 4 county-level schools. The cumulative sum methods(CUSUM) was used to detect abnormal signals. A susceptible-exposed-infectious/asymptomatic-recovered (SEIAR) model was fit to the influenza outbreak without control measures and compared with the actual influenza outbreak to evaluate the effectiveness of early control efforts. The ILI incidence rates in 2014 (14.51%) was higher than the incidence in 2013 (5.27%) and 2012 (3.59%). Ten school influenza outbreaks were detected by CUSUM. Each outbreak had high transmissibility with a median Runc of 4.62. The interventions in each outbreak had high effectiveness and all Rcon were 0. The early intervention had high effectiveness within the school-based ILI syndromic surveillance. Syndromic surveillance within schools can play an important role in controlling influenza outbreaks.
Jack, Mhairi; Futro, Agnieszka; Talbot, Darren; Zhu, Qiming; Barclay, David; Baxter, Emma M.
2018-01-01
Tail biting is a major welfare and economic problem for indoor pig producers worldwide. Low tail posture is an early warning sign which could reduce tail biting unpredictability. Taking a precision livestock farming approach, we used Time-of-flight 3D cameras, processing data with machine vision algorithms, to automate the measurement of pig tail posture. Validation of the 3D algorithm found an accuracy of 73.9% at detecting low vs. not low tails (Sensitivity 88.4%, Specificity 66.8%). Twenty-three groups of 29 pigs per group were reared with intact (not docked) tails under typical commercial conditions over 8 batches. 15 groups had tail biting outbreaks, following which enrichment was added to pens and biters and/or victims were removed and treated. 3D data from outbreak groups showed the proportion of low tail detections increased pre-outbreak and declined post-outbreak. Pre-outbreak, the increase in low tails occurred at an increasing rate over time, and the proportion of low tails was higher one week pre-outbreak (-1) than 2 weeks pre-outbreak (-2). Within each batch, an outbreak and a non-outbreak control group were identified. Outbreak groups had more 3D low tail detections in weeks -1, +1 and +2 than their matched controls. Comparing 3D tail posture and tail injury scoring data, a greater proportion of low tails was associated with more injured pigs. Low tails might indicate more than just tail biting as tail posture varied between groups and over time and the proportion of low tails increased when pigs were moved to a new pen. Our findings demonstrate the potential for a 3D machine vision system to automate tail posture detection and provide early warning of tail biting on farm. PMID:29617403
Data modeling for detection of epidemic outbreak
NASA Astrophysics Data System (ADS)
Jaenisch, Holger M.; Handley, James W.; Jaenisch, Kristina L.; Conn, Michael S.; Faucheux, Jeffrey P.
2005-05-01
Data Modeling is successfully applied to outbreak detection using epidemicological time series data. With proper selection of features, same day detection was demonstrated. Predictive Data Models are derived from the features in the form of integro-differential equations or their solution. These models are used as real-time change detectors. Data Modeling enables change detection using only nominal (no-outbreak) examples for training. Modeling naturally occurring dynamics due to assignable causes such as flu season enables distinction to be made of chemical and biological (chem-bio) causes.
Schafer, Ilana J; Knudsen, Erik; McNamara, Lucy A; Agnihotri, Sachin; Rollin, Pierre E; Islam, Asad
2016-10-15
The Epi Info Viral Hemorrhagic Fever application (Epi Info VHF) was developed in response to challenges managing outbreak data during four 2012 filovirus outbreaks. Development goals included combining case and contact data in a relational database, facilitating data-driven contact tracing, and improving outbreak data consistency and use. The application was first deployed in Guinea, when the West Africa Ebola epidemic was detected, in March 2014, and has been used in 7 African countries and 2 US states. Epi Info VHF enabled reporting of compatible data from multiple countries, contributing to international Ebola knowledge. However, challenges were encountered in accommodating the epidemic's unexpectedly large magnitude, addressing country-specific needs within 1 software product, and using the application in settings with limited Internet access and information technology support. Use of Epi Info VHF in the West Africa Ebola epidemic highlighted the fundamental importance of good data management for effective outbreak response, regardless of the software used. Published by Oxford University Press for the Infectious Diseases Society of America 2016. This work is written by (a) US Government employee(s) and is in the public domain in the US.
Signature-forecasting and early outbreak detection system
Naumova, Elena N.; MacNeill, Ian B.
2008-01-01
SUMMARY Daily disease monitoring via a public health surveillance system provides valuable information on population risks. Efficient statistical tools for early detection of rapid changes in the disease incidence are a must for modern surveillance. The need for statistical tools for early detection of outbreaks that are not based on historical information is apparent. A system is discussed for monitoring cases of infections with a view to early detection of outbreaks and to forecasting the extent of detected outbreaks. We propose a set of adaptive algorithms for early outbreak detection that does not rely on extensive historical recording. We also include knowledge of infection disease epidemiology into forecasts. To demonstrate this system we use data from the largest water-borne outbreak of cryptosporidiosis, which occurred in Milwaukee in 1993. Historical data are smoothed using a loess-type smoother. Upon receipt of a new datum, the smoothing is updated and estimates are made of the first two derivatives of the smooth curve, and these are used for near-term forecasting. Recent data and the near-term forecasts are used to compute a color-coded warning index, which quantify the level of concern. The algorithms for computing the warning index have been designed to balance Type I errors (false prediction of an epidemic) and Type II errors (failure to correctly predict an epidemic). If the warning index signals a sufficiently high probability of an epidemic, then a forecast of the possible size of the outbreak is made. This longer term forecast is made by fitting a ‘signature’ curve to the available data. The effectiveness of the forecast depends upon the extent to which the signature curve captures the shape of outbreaks of the infection under consideration. PMID:18716671
Chan, J Hy; Law, C K; Hamblion, E; Fung, H; Rudge, J
2017-04-01
Hand, foot, and mouth disease continues to cause seasonal epidemics in the Asia-Pacific Region. Since the current Enterovirus 71 vaccines do not provide cross-protection for all Enterovirus species that cause hand, foot, and mouth disease, there is an urgent need to identify appropriate detection tools and best practice to prevent its transmission and to effectively control its outbreaks. This systematic review aimed to identify characteristics of outbreak and assess the impact and effectiveness of detection tools and public health preventive measures to interrupt transmission. The findings will be used to recommend policy on the most effective responses and interventions in Hong Kong to effectively minimise and contain the spread of the disease within childcare facilities. We searched the following databases for primary studies written in Chinese or English: MEDLINE, EMBASE, Global Health, WHO Western Pacific Region Index Medicus database, China National Knowledge Infrastructure Databases, and Chinese Scientific Journals Database. Studies conducted during or retrospective to outbreaks of hand, foot, and mouth disease caused by Enterovirus 71 from 1980 to 2012 within childcare facilities and with a study population of 0 to 6 years old were included. Sixteen studies conducted on outbreaks in China showed that hand, foot, and mouth disease spread rapidly within the facility, with an outbreak length of 4 to 46 days, especially in those with delayed notification (after 24 hours) of clustered outbreak (with five or more cases discovered within the facility) to the local Center for Disease Control and Prevention and delayed implementation of a control response. The number of classes affected ranged from 1 to 13, and the attack rate for children ranged from 0.97% to 28.18%. Communication between key stakeholders about outbreak confirmation, risk assessment, and surveillance should be improved. Effective communication facilitates timely notification (within 24 hours) of clustered outbreaks to a local Center for Disease Control and Prevention. Timely implementation of a control response is effective in minimising incidence and length of an outbreak in childcare facilities. The government should provide incentives for childcare facilities to train infection control specialists who can serve as the first contact, knowledge, and communication points, as well as facilitate exchange of information and provision of support across stakeholders during a communicable disease epidemic.
Recombinant Temporal Aberration Detection Algorithms for Enhanced Biosurveillance
Murphy, Sean Patrick; Burkom, Howard
2008-01-01
Objective Broadly, this research aims to improve the outbreak detection performance and, therefore, the cost effectiveness of automated syndromic surveillance systems by building novel, recombinant temporal aberration detection algorithms from components of previously developed detectors. Methods This study decomposes existing temporal aberration detection algorithms into two sequential stages and investigates the individual impact of each stage on outbreak detection performance. The data forecasting stage (Stage 1) generates predictions of time series values a certain number of time steps in the future based on historical data. The anomaly measure stage (Stage 2) compares features of this prediction to corresponding features of the actual time series to compute a statistical anomaly measure. A Monte Carlo simulation procedure is then used to examine the recombinant algorithms’ ability to detect synthetic aberrations injected into authentic syndromic time series. Results New methods obtained with procedural components of published, sometimes widely used, algorithms were compared to the known methods using authentic datasets with plausible stochastic injected signals. Performance improvements were found for some of the recombinant methods, and these improvements were consistent over a range of data types, outbreak types, and outbreak sizes. For gradual outbreaks, the WEWD MovAvg7+WEWD Z-Score recombinant algorithm performed best; for sudden outbreaks, the HW+WEWD Z-Score performed best. Conclusion This decomposition was found not only to yield valuable insight into the effects of the aberration detection algorithms but also to produce novel combinations of data forecasters and anomaly measures with enhanced detection performance. PMID:17947614
Kroeger, Axel; Runge-Ranzinger, Silvia; O'Dempsey, Tim
2013-01-01
Background. Dengue outbreaks are occurring with increasing frequency and intensity. Evidence-based epidemic preparedness and effective response are now a matter of urgency. Therefore, we have analysed national and municipal dengue outbreak response plans. Methods. Thirteen country plans from Asia, Latin America and Australia, and one international plan were obtained from the World Health Organization. The information was transferred to a data analysis matrix where information was extracted according to predefined and emerging themes and analysed for scope, inconsistencies, omissions, and usefulness. Findings. Outbreak response planning currently has a considerable number of flaws. Outbreak governance was weak with a lack of clarity of stakeholder roles. Late timing of responses due to poor surveillance, a lack of combining routine data with additional alerts, and lack of triggers for initiating the response weakened the functionality of plans. Frequently an outbreak was not defined, and early response mechanisms based on alert signals were neglected. There was a distinct lack of consideration of contextual influences which can affect how an outbreak detection and response is managed. Conclusion. A model contingency plan for dengue outbreak prediction, detection, and response may help national disease control authorities to develop their own more detailed and functional context specific plans. PMID:24222774
Transmission, Human Population, and Pathogenicity: the Ebola Case in Point.
Delgado, Rafael; Simón, Fernando
2018-03-01
The 2013-2016 Ebola outbreak in West Africa has been the largest ever of a known disease in a new context that produced an unprecedented impact and is changing the international approach to responding to public health emergencies. The unprecedented scale of the outbreak, the use of advanced technology for detecting and characterizing the infectious agent, along with the opportunity to treat patients in modern facilities have greatly increased our knowledge of the disease and its transmission. Also, for the first time, an important international effort has been deployed to control the spread of the epidemic by providing care to patients and by adopting basic measures of public health control. Apart from supportive treatment and intensive therapy with fluids and electrolytes, no new compounds have been proved to be clinically effective to treat Ebola virus disease; however, a specific vaccine has shown significant protection in clinical trials in Guinea, opening an expectation for controlling future outbreaks.
Bjelkmar, Pär; Hansen, Anette; Schönning, Caroline; Bergström, Jakob; Löfdahl, Margareta; Lebbad, Marianne; Wallensten, Anders; Allestam, Görel; Stenmark, Stephan; Lindh, Johan
2017-04-18
In the winter and spring of 2011 a large outbreak of cryptosporidiosis occurred in Skellefteå municipality, Sweden. This study summarizes the outbreak investigation in terms of outbreak size, duration, clinical characteristics, possible source(s) and the potential for earlier detection using calls to a health advice line. The investigation included two epidemiological questionnaires and microbial analysis of samples from patients, water and other environmental sources. In addition, a retrospective study based on phone calls to a health advice line was performed by comparing patterns of phone calls between different water distribution areas. Our analyses showed that approximately 18,500 individuals were affected by a waterborne outbreak of cryptosporidiosis in Skellefteå in 2011. This makes it the second largest outbreak of cryptosporidiosis in Europe to date. Cryptosporidium hominis oocysts of subtype IbA10G2 were found in patient and sewage samples, but not in raw water or in drinking water, and the initial contamination source could not be determined. The outbreak went unnoticed to authorities for several months. The analysis of the calls to the health advice line provides strong indications early in the outbreak that it was linked to a particular water treatment plant. We conclude that an earlier detection of the outbreak by linking calls to a health advice line to water distribution areas could have limited the outbreak substantially.
Hogan, William R.; Tsui, Fu-Chiang; Ivanov, Oleg; Gesteland, Per H.; Grannis, Shaun; Overhage, J. Marc; Robinson, J. Michael; Wagner, Michael M.
2003-01-01
Objective: To determine whether sales of electrolyte products contain a signal of outbreaks of respiratory and diarrheal disease in children and, if so, how much earlier a signal relative to hospital diagnoses. Design: Retrospective analysis was conducted of sales of electrolyte products and hospital diagnoses for six urban regions in three states for the period 1998 through 2001. Measurements: Presence of signal was ascertained by measuring correlation between electrolyte sales and hospital diagnoses and the temporal relationship that maximized correlation. Earliness was the difference between the date that the exponentially weighted moving average (EWMA) method first detected an outbreak from sales and the date it first detected the outbreak from diagnoses. The coefficient of determination (r2) measured how much variance in earliness resulted from differences in sales' and diagnoses' signal strengths. Results: The correlation between electrolyte sales and hospital diagnoses was 0.90 (95% CI, 0.87–0.93) at a time offset of 1.7 weeks (95% CI, 0.50–2.9), meaning that sales preceded diagnoses by 1.7 weeks. EWMA with a nine-sigma threshold detected the 18 outbreaks on average 2.4 weeks (95% CI, 0.1–4.8 weeks) earlier from sales than from diagnoses. Twelve outbreaks were first detected from sales, four were first detected from diagnoses, and two were detected simultaneously. Only 26% of variance in earliness was explained by the relative strength of the sales and diagnoses signals (r2 = 0.26). Conclusion: Sales of electrolyte products contain a signal of outbreaks of respiratory and diarrheal diseases in children and usually are an earlier signal than hospital diagnoses. PMID:12925542
Yamaguchi, Noriyuki; Hupp, Jerry W.; Higuchi, Hiroyoshi; Flint, Paul L.; Pearce, John M.
2010-01-01
We fitted Northern Pintail Anas acuta in Japan with satellite transmitters and monitored their spring migration movements relative to locations where the highly pathogenic H5N1 avian influenza virus was detected in Whooper Swans Cygnus cygnus in 2008. Pintails were assumed not to be infected with the H5N1 virus at the time they were marked because capture occurred between 2 and 5 months before reported outbreaks of the virus in Japan. We assessed spatial and temporal overlap between marked birds and occurrence of the virus and tracked Pintails after they departed outbreak locations. Eight of 66 (12.1%) Northern Pintails marked with satellite transmitters used wetlands in Japan where the H5N1 virus was detected in Whooper Swans. Apparent survival did not differ between Pintails that used H5N1 sites and those that did not. However, the proportion of Pintails that migrated from Japan was significantly lower among birds that used H5N1 sites compared with those that did not (0.50 vs. 0.79). Northern Pintails were present at the H5N1 sites from 1 to 88 days, with five birds present at the sites from 0 to 7 days prior to detection of the virus in Swans. The six Pintails observed to depart H5N1 sites did so within 2–77 days of the reported outbreaks and moved between 6 and 1200 km within 4 days of departure. Four Pintails migrated to eastern Russia. After their departure from outbreak sites, Northern Pintails made long‐distance migrations within the period when newly infected ducks would shed the H5N1 virus. This supports a hypothesized mechanism by which a highly pathogenic avian influenza virus could be spread by migratory birds.
Social media posts and online search behaviour as early-warning system for MRSA outbreaks.
van de Belt, Tom H; van Stockum, Pieter T; Engelen, Lucien J L P G; Lancee, Jules; Schrijver, Remco; Rodríguez-Baño, Jesús; Tacconelli, Evelina; Saris, Katja; van Gelder, Marleen M H J; Voss, Andreas
2018-01-01
Despite many preventive measures, outbreaks with multi-drug resistant micro-organisms (MDROs) still occur. Moreover, current alert systems from healthcare organizations have shortcomings due to delayed or incomplete notifications, which may amplify the spread of MDROs by introducing infected patients into a new healthcare setting and institutions. Additional sources of information about upcoming and current outbreaks, may help to prevent further spread of MDROs.The study objective was to evaluate whether methicillin-resistant Staphylococcus aureus (MRSA) outbreaks could be detected via social media posts or online search behaviour; if so, this might allow earlier detection than the official notifications by healthcare organizations. We conducted an exploratory study in which we compared information about MRSA outbreaks in the Netherlands derived from two online sources, Coosto for Social Media, and Google Trends for search behaviour, to the mandatory Dutch outbreak notification system (SO-ZI/AMR). The latter provides information on MDRO outbreaks including the date of the outbreak, micro-organism involved, the region/location, and the type of health care organization. During the research period of 15 months (455 days), 49 notifications of outbreaks were recorded in SO-ZI/AMR. For Coosto, the number of unique potential outbreaks was 37 and for Google Trends 24. The use of social media and online search behaviour missed many of the hospital outbreaks that were reported to SO-ZI/AMR, but detected additional outbreaks in long-term care facilities. Despite several limitations, using information from social media and online search behaviour allows rapid identification of potential MRSA outbreaks, especially in healthcare settings with a low notification compliance. When combined in an automated system with real-time updates, this approach might increase early discovery and subsequent implementation of preventive measures.
Whole Genome Sequencing for Genomics-Guided Investigations of Escherichia coli O157:H7 Outbreaks.
Rusconi, Brigida; Sanjar, Fatemeh; Koenig, Sara S K; Mammel, Mark K; Tarr, Phillip I; Eppinger, Mark
2016-01-01
Multi isolate whole genome sequencing (WGS) and typing for outbreak investigations has become a reality in the post-genomics era. We applied this technology to strains from Escherichia coli O157:H7 outbreaks. These include isolates from seven North America outbreaks, as well as multiple isolates from the same patient and from different infected individuals in the same household. Customized high-resolution bioinformatics sequence typing strategies were developed to assess the core genome and mobilome plasticity. Sequence typing was performed using an in-house single nucleotide polymorphism (SNP) discovery and validation pipeline. Discriminatory power becomes of particular importance for the investigation of isolates from outbreaks in which macrogenomic techniques such as pulse-field gel electrophoresis or multiple locus variable number tandem repeat analysis do not differentiate closely related organisms. We also characterized differences in the phage inventory, allowing us to identify plasticity among outbreak strains that is not detectable at the core genome level. Our comprehensive analysis of the mobilome identified multiple plasmids that have not previously been associated with this lineage. Applied phylogenomics approaches provide strong molecular evidence for exceptionally little heterogeneity of strains within outbreaks and demonstrate the value of intra-cluster comparisons, rather than basing the analysis on archetypal reference strains. Next generation sequencing and whole genome typing strategies provide the technological foundation for genomic epidemiology outbreak investigation utilizing its significantly higher sample throughput, cost efficiency, and phylogenetic relatedness accuracy. These phylogenomics approaches have major public health relevance in translating information from the sequence-based survey to support timely and informed countermeasures. Polymorphisms identified in this work offer robust phylogenetic signals that index both short- and long-term evolution and can complement currently employed typing schemes for outbreak ex- and inclusion, diagnostics, surveillance, and forensic studies.
Whole Genome Sequencing for Genomics-Guided Investigations of Escherichia coli O157:H7 Outbreaks
Rusconi, Brigida; Sanjar, Fatemeh; Koenig, Sara S. K.; Mammel, Mark K.; Tarr, Phillip I.; Eppinger, Mark
2016-01-01
Multi isolate whole genome sequencing (WGS) and typing for outbreak investigations has become a reality in the post-genomics era. We applied this technology to strains from Escherichia coli O157:H7 outbreaks. These include isolates from seven North America outbreaks, as well as multiple isolates from the same patient and from different infected individuals in the same household. Customized high-resolution bioinformatics sequence typing strategies were developed to assess the core genome and mobilome plasticity. Sequence typing was performed using an in-house single nucleotide polymorphism (SNP) discovery and validation pipeline. Discriminatory power becomes of particular importance for the investigation of isolates from outbreaks in which macrogenomic techniques such as pulse-field gel electrophoresis or multiple locus variable number tandem repeat analysis do not differentiate closely related organisms. We also characterized differences in the phage inventory, allowing us to identify plasticity among outbreak strains that is not detectable at the core genome level. Our comprehensive analysis of the mobilome identified multiple plasmids that have not previously been associated with this lineage. Applied phylogenomics approaches provide strong molecular evidence for exceptionally little heterogeneity of strains within outbreaks and demonstrate the value of intra-cluster comparisons, rather than basing the analysis on archetypal reference strains. Next generation sequencing and whole genome typing strategies provide the technological foundation for genomic epidemiology outbreak investigation utilizing its significantly higher sample throughput, cost efficiency, and phylogenetic relatedness accuracy. These phylogenomics approaches have major public health relevance in translating information from the sequence-based survey to support timely and informed countermeasures. Polymorphisms identified in this work offer robust phylogenetic signals that index both short- and long-term evolution and can complement currently employed typing schemes for outbreak ex- and inclusion, diagnostics, surveillance, and forensic studies. PMID:27446025
Evaluation of Syndromic Surveillance Systems in 6 US State and Local Health Departments.
Thomas, Mathew J; Yoon, Paula W; Collins, James M; Davidson, Arthur J; Mac Kenzie, William R
Evaluating public health surveillance systems is critical to ensuring that conditions of public health importance are appropriately monitored. Our objectives were to qualitatively evaluate 6 state and local health departments that were early adopters of syndromic surveillance in order to (1) understand the characteristics and current uses, (2) identify the most and least useful syndromes to monitor, (3) gauge the utility for early warning and outbreak detection, and (4) assess how syndromic surveillance impacted their daily decision making. We adapted evaluation guidelines from the Centers for Disease Control and Prevention and gathered input from the Centers for Disease Control and Prevention subject matter experts in public health surveillance to develop a questionnaire. We interviewed staff members from a convenience sample of 6 local and state health departments with syndromic surveillance programs that had been in operation for more than 10 years. Three of the 6 interviewees provided an example of using syndromic surveillance to identify an outbreak (ie, cluster of foodborne illness in 1 jurisdiction) or detect a surge in cases for seasonal conditions (eg, influenza in 2 jurisdictions) prior to traditional, disease-specific systems. Although all interviewees noted that syndromic surveillance has not been routinely useful or efficient for early outbreak detection or case finding in their jurisdictions, all agreed that the information can be used to improve their understanding of dynamic disease control environments and conditions (eg, situational awareness) in their communities. In the jurisdictions studied, syndromic surveillance may be useful for monitoring the spread and intensity of large outbreaks of disease, especially influenza; enhancing public health awareness of mass gatherings and natural disasters; and assessing new, otherwise unmonitored conditions when real-time alternatives are unavailable. Future studies should explore opportunities to strengthen syndromic surveillance by including broader access to and enhanced analysis of text-related data from electronic health records. Health departments may accelerate the development and use of syndromic surveillance systems, including the improvement of the predictive value and strengthening the early outbreak detection capability of these systems. These efforts support getting the right information to the right people at the right time, which is the overarching goal of CDC's Surveillance Strategy.
A space-time scan statistic for detecting emerging outbreaks.
Tango, Toshiro; Takahashi, Kunihiko; Kohriyama, Kazuaki
2011-03-01
As a major analytical method for outbreak detection, Kulldorff's space-time scan statistic (2001, Journal of the Royal Statistical Society, Series A 164, 61-72) has been implemented in many syndromic surveillance systems. Since, however, it is based on circular windows in space, it has difficulty correctly detecting actual noncircular clusters. Takahashi et al. (2008, International Journal of Health Geographics 7, 14) proposed a flexible space-time scan statistic with the capability of detecting noncircular areas. It seems to us, however, that the detection of the most likely cluster defined in these space-time scan statistics is not the same as the detection of localized emerging disease outbreaks because the former compares the observed number of cases with the conditional expected number of cases. In this article, we propose a new space-time scan statistic which compares the observed number of cases with the unconditional expected number of cases, takes a time-to-time variation of Poisson mean into account, and implements an outbreak model to capture localized emerging disease outbreaks more timely and correctly. The proposed models are illustrated with data from weekly surveillance of the number of absentees in primary schools in Kitakyushu-shi, Japan, 2006. © 2010, The International Biometric Society.
Martínez-Torres, A. O.; Mosquera, M. M.; Sanz, J. C.; Ramos, B.; Echevarría, J. E.
2009-01-01
An outbreak of rubella affected 460 individuals in 2004 and 2005 in the community of Madrid, Spain. Most of the patients were nonvaccinated Latin American immigrants or Spanish males. This study presents the first data on rubella virus genotypes in Spain. Forty selected clinical samples (2 urine, 5 serum, 3 blood, 2 saliva, and 28 pharyngeal exudate samples) from 40 cases were collected. The 739-nucleotide sequence recommended by the World Health Organization obtained from viral RNA in these samples was analyzed by using the MEGA v4.0 software. Seventeen isolates were obtained from 40 clinical samples from the outbreak, including two isolated from congenital rubella syndrome cases. Only viral RNA of genotype 1j was detected in both isolates and clinical specimens. Two variations in amino acids, G253C and T394S, which are involved in neutralization epitopes arose during the outbreak, but apparently there was no positive selection of either of them. The origin of the outbreak remains unknown because of poor virologic surveillance in Latin America and the African countries neighboring Spain. On the other hand, this is the first report of this genotype in Europe. The few published sequences of genotype 1j indicate that it comes from Japan and the Philippines, but there are no epidemiological data supporting this as the origin of the Madrid outbreak. PMID:19020066
Genomics-enabled sensor platform for rapid detection of viruses related to disease outbreak.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Brozik, Susan M; Manginell, Ronald P; Moorman, Matthew W
2013-09-01
Bioweapons and emerging infectious diseases pose growing threats to our national security. Both natural disease outbreak and outbreaks due to a bioterrorist attack are a challenge to detect, taking days after the outbreak to identify since most outbreaks are only recognized through reportable diseases by health departments and reports of unusual diseases by clinicians. In recent decades, arthropod-borne viruses (arboviruses) have emerged as some of the most significant threats to human health. They emerge, often unexpectedly, from cryptic transmission foci causing localized outbreaks that can rapidly spread to multiple continents due to increased human travel and trade. Currently, diagnosis ofmore » acute infections requires amplification of viral nucleic acids, which can be costly, highly specific, technically challenging and time consuming. No diagnostic devices suitable for use at the bedside or in an outbreak setting currently exist. The original goals of this project were to 1) develop two highly sensitive and specific diagnostic assays for detecting RNA from a wide range of arboviruses; one based on an electrochemical approach and the other a fluorescent based assay and 2) develop prototype microfluidic diagnostic platforms for preclinical and field testing that utilize the assays developed in goal 1. We generated and characterized suitable primers for West Nile Virus RNA detection. Both optical and electrochemical transduction technologies were developed for DNA-RNA hybridization detection and were implemented in microfluidic diagnostic sensing platforms that were developed in this project.« less
Leslie, E; Cowled, B; Graeme Garner, M; Toribio, J-A L M L; Ward, M P
2014-10-01
Early disease detection and efficient methods of proving disease freedom can substantially improve the response to incursions of important transboundary animal diseases in previously free regions. We used a spatially explicit, stochastic disease spread model to simulate the spread of classical swine fever in wild pigs in a remote region of northern Australia and to assess the performance of disease surveillance strategies to detect infection at different time points and to delineate the size of the resulting outbreak. Although disease would likely be detected, simple random sampling was suboptimal. Radial and leapfrog sampling improved the effectiveness of surveillance at various stages of the simulated disease incursion. This work indicates that at earlier stages, radial sampling can reduce epidemic length and achieve faster outbreak delineation and control, but at later stages leapfrog sampling will outperform radial sampling in relation to supporting faster disease control with a less-extensive outbreak area. Due to the complexity of wildlife population dynamics and group behaviour, a targeted approach to surveillance needs to be implemented for the efficient use of resources and time. Using a more situation-based surveillance approach and accounting for disease distribution and the time period over which an epidemic has occurred is the best way to approach the selection of an appropriate surveillance strategy. © 2013 Blackwell Verlag GmbH.
The use of hospital-based nurses for the surveillance of potential disease outbreaks.
Durrheim, D. N.; Harris, B. N.; Speare, R.; Billinghurst, K.
2001-01-01
OBJECTIVE: To study a novel surveillance system introduced in Mpumalanga Province, a rural area in the north-east of South Africa, in an attempt to address deficiencies in the system of notification for infectious conditions that have the potential for causing outbreaks. METHODS: Hospital-based infection control nurses in all of Mpumalanga's 32 public and private hospitals were trained to recognize, report, and respond to nine clinical syndromes that require immediate action. Sustainability of the system was assured through a schedule of regular training and networking, and by providing feedback to the nurses. The system was evaluated by formal review of hospital records, evidence of the effective containment of a cholera outbreak, and assessment of the speed and appropriateness of responses to other syndromes. FINDINGS: Rapid detection, reporting and response to six imported cholera cases resulted in effective containment, with only 19 proven secondary cholera cases, during the two-year review period. No secondary cases followed detection and prompt response to 14 patients with meningococcal disease. By the end of the first year of implementation, all facilities were providing weekly zero-reports on the nine syndromes before the designated time. Formal hospital record review for cases of acute flaccid paralysis endorsed the value of the system. CONCLUSION: The primary goal of an outbreak surveillance system is to ensure timely recognition of syndromes requiring an immediate response. Infection control nurses in Mpumalanga hospitals have excelled in timely weekly zero-reporting, participation at monthly training and feedback sessions, detection of priority clinical syndromes, and prompt appropriate response. This review provides support for the role of hospital-based nurses as valuable sentinel surveillance agents providing timely data for action. PMID:11217663
Mouchtouri, Varvara A; Verykouki, Eleni; Zamfir, Dumitru; Hadjipetris, Christos; Lewis, Hannah C; Hadjichristodoulou, Christos
2017-11-01
When an increased number of acute gastroenteritis (AG) cases is detected among tourists staying at the same accommodation, outbreak management plans must be activated in a timely manner to prevent large outbreaks. Syndromic surveillance data collected between 1 January 2010 and 31 December 2013 by five seagoing cruise ships were analysed to identify attack rate thresholds for early outbreak detection. The overall incidence rate of AG was 2.81 cases per 10,000 traveller-days (95% confidence interval (CI): 0.00-17.60), while the attack rate was 19.37 cases per 10,000 travellers (95% CI: 0.00-127.69). The probability of an outbreak occurring was 11% if 4 per 1,000 passengers reported symptoms within the first 2 days of the voyage, and this increased to 23 % if 5 per 1,000 passengers reported such within the first 3 days. The risk ratio (RR) for outbreak occurrence was 2.35, 5.66 and 8.63 for 1, 2 and 3 days' delay of symptoms reporting respectively, suggesting a dose-response relationship. Shipping companies' policies and health authorities' efforts may consider these thresholds for initiating outbreak response measures based on the number of cases according to day of cruise. Efforts should focus on ensuring travellers report symptoms immediately and comply with isolation measures.
Fankhauser, R L; Noel, J S; Monroe, S S; Ando, T; Glass, R I
1998-12-01
Fecal specimens from 90 outbreaks of nonbacterial gastroenteritis reported to 33 state health departments from January 1996 to June 1997 were examined to determine the importance of and to characterize "Norwalk-like viruses" (NLVs) in these outbreaks. NLVs were detected by reverse transcription-polymerase chain reaction in specimens from 86 (96%) of 90 outbreaks. Outbreaks were most frequent in nursing homes and hospitals (43%), followed by restaurants or events with catered meals (26%); consumption of contaminated food was the most commonly identified mode of transmission (37%). Nucleotide sequence analysis showed great diversity between strains but also provided evidence indicating the emergence of a common, predominant strain. The application of improved molecular techniques to detect NLVs demonstrates that most outbreaks of nonbacterial gastroenteritis in the United States appear to be associated with these viruses and that sequence analysis is a robust tool to help link or differentiate these outbreaks.
Charles-Smith, Lauren E; Reynolds, Tera L; Cameron, Mark A; Conway, Mike; Lau, Eric H Y; Olsen, Jennifer M; Pavlin, Julie A; Shigematsu, Mika; Streichert, Laura C; Suda, Katie J; Corley, Courtney D
2015-01-01
Research studies show that social media may be valuable tools in the disease surveillance toolkit used for improving public health professionals' ability to detect disease outbreaks faster than traditional methods and to enhance outbreak response. A social media work group, consisting of surveillance practitioners, academic researchers, and other subject matter experts convened by the International Society for Disease Surveillance, conducted a systematic primary literature review using the PRISMA framework to identify research, published through February 2013, answering either of the following questions: Can social media be integrated into disease surveillance practice and outbreak management to support and improve public health?Can social media be used to effectively target populations, specifically vulnerable populations, to test an intervention and interact with a community to improve health outcomes?Examples of social media included are Facebook, MySpace, microblogs (e.g., Twitter), blogs, and discussion forums. For Question 1, 33 manuscripts were identified, starting in 2009 with topics on Influenza-like Illnesses (n = 15), Infectious Diseases (n = 6), Non-infectious Diseases (n = 4), Medication and Vaccines (n = 3), and Other (n = 5). For Question 2, 32 manuscripts were identified, the first in 2000 with topics on Health Risk Behaviors (n = 10), Infectious Diseases (n = 3), Non-infectious Diseases (n = 9), and Other (n = 10). The literature on the use of social media to support public health practice has identified many gaps and biases in current knowledge. Despite the potential for success identified in exploratory studies, there are limited studies on interventions and little use of social media in practice. However, information gleaned from the articles demonstrates the effectiveness of social media in supporting and improving public health and in identifying target populations for intervention. A primary recommendation resulting from the review is to identify opportunities that enable public health professionals to integrate social media analytics into disease surveillance and outbreak management practice.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Charles-Smith, Lauren E.; Reynolds, Tera L.; Cameron, Mark A.
Here, research studies show that social media may be valuable tools in the disease surveillance toolkit used for improving public health professionals’ ability to detect disease outbreaks faster than traditional methods and to enhance outbreak response. A social media work group, consisting of surveillance practitioners, academic researchers, and other subject matter experts convened by the International Society for Disease Surveillance, conducted a systematic primary literature review using the PRISMA framework to identify research, published through February 2013, answering either of the following questions: 1) Can social media be integrated into disease surveillance practice and outbreak management to support and improvemore » public health? 2) Can social media be used to effectively target populations, specifically vulnerable populations, to test an intervention and interact with a community to improve health outcomes? Examples of social media included are Facebook, MySpace, microblogs (e.g., Twitter), blogs, and discussion forums. For Question 1, 33 manuscripts were identified, starting in 2009 with topics on Influenza-like Illnesses (n=15), Infectious Diseases (n = 6), Non-infectious Diseases (n=4), Medication and Vaccines (n=3), and Other (n=5). For Question 2, 32 manuscripts were identified, the first in 2000 with topics on Health Risk Behaviors (n=10), Infectious Diseases (n = 3), Non-infectious Diseases (n=9), and Other (n=10). The literature on the use of social media to support public health practice has identified many gaps and biases in current knowledge. Despite the potential for success identified in exploratory studies, there are limited studies on interventions and little use of social media in practice. However, information gleaned from the articles demonstrates the effectiveness of social media in supporting and improving public health and in identifying target populations for intervention. A primary recommendation resulting from the review is to identify opportunities that enable public health professionals to integrate social media analytics into disease surveillance and outbreak management practice.« less
Charles-Smith, Lauren E.; Reynolds, Tera L.; Cameron, Mark A.; Conway, Mike; Lau, Eric H. Y.; Olsen, Jennifer M.; Pavlin, Julie A.; Shigematsu, Mika; Streichert, Laura C.; Suda, Katie J.; Corley, Courtney D.
2015-01-01
Objective Research studies show that social media may be valuable tools in the disease surveillance toolkit used for improving public health professionals’ ability to detect disease outbreaks faster than traditional methods and to enhance outbreak response. A social media work group, consisting of surveillance practitioners, academic researchers, and other subject matter experts convened by the International Society for Disease Surveillance, conducted a systematic primary literature review using the PRISMA framework to identify research, published through February 2013, answering either of the following questions: Can social media be integrated into disease surveillance practice and outbreak management to support and improve public health? Can social media be used to effectively target populations, specifically vulnerable populations, to test an intervention and interact with a community to improve health outcomes? Examples of social media included are Facebook, MySpace, microblogs (e.g., Twitter), blogs, and discussion forums. For Question 1, 33 manuscripts were identified, starting in 2009 with topics on Influenza-like Illnesses (n = 15), Infectious Diseases (n = 6), Non-infectious Diseases (n = 4), Medication and Vaccines (n = 3), and Other (n = 5). For Question 2, 32 manuscripts were identified, the first in 2000 with topics on Health Risk Behaviors (n = 10), Infectious Diseases (n = 3), Non-infectious Diseases (n = 9), and Other (n = 10). Conclusions The literature on the use of social media to support public health practice has identified many gaps and biases in current knowledge. Despite the potential for success identified in exploratory studies, there are limited studies on interventions and little use of social media in practice. However, information gleaned from the articles demonstrates the effectiveness of social media in supporting and improving public health and in identifying target populations for intervention. A primary recommendation resulting from the review is to identify opportunities that enable public health professionals to integrate social media analytics into disease surveillance and outbreak management practice. PMID:26437454
Charles-Smith, Lauren E.; Reynolds, Tera L.; Cameron, Mark A.; ...
2015-10-05
Here, research studies show that social media may be valuable tools in the disease surveillance toolkit used for improving public health professionals’ ability to detect disease outbreaks faster than traditional methods and to enhance outbreak response. A social media work group, consisting of surveillance practitioners, academic researchers, and other subject matter experts convened by the International Society for Disease Surveillance, conducted a systematic primary literature review using the PRISMA framework to identify research, published through February 2013, answering either of the following questions: 1) Can social media be integrated into disease surveillance practice and outbreak management to support and improvemore » public health? 2) Can social media be used to effectively target populations, specifically vulnerable populations, to test an intervention and interact with a community to improve health outcomes? Examples of social media included are Facebook, MySpace, microblogs (e.g., Twitter), blogs, and discussion forums. For Question 1, 33 manuscripts were identified, starting in 2009 with topics on Influenza-like Illnesses (n=15), Infectious Diseases (n = 6), Non-infectious Diseases (n=4), Medication and Vaccines (n=3), and Other (n=5). For Question 2, 32 manuscripts were identified, the first in 2000 with topics on Health Risk Behaviors (n=10), Infectious Diseases (n = 3), Non-infectious Diseases (n=9), and Other (n=10). The literature on the use of social media to support public health practice has identified many gaps and biases in current knowledge. Despite the potential for success identified in exploratory studies, there are limited studies on interventions and little use of social media in practice. However, information gleaned from the articles demonstrates the effectiveness of social media in supporting and improving public health and in identifying target populations for intervention. A primary recommendation resulting from the review is to identify opportunities that enable public health professionals to integrate social media analytics into disease surveillance and outbreak management practice.« less
Tseng, Yi-Ju; Wu, Jung-Hsuan; Ping, Xiao-Ou; Lin, Hui-Chi; Chen, Ying-Yu; Shang, Rung-Ji; Chen, Ming-Yuan; Lai, Feipei
2012-01-01
Background The emergence and spread of multidrug-resistant organisms (MDROs) are causing a global crisis. Combating antimicrobial resistance requires prevention of transmission of resistant organisms and improved use of antimicrobials. Objectives To develop a Web-based information system for automatic integration, analysis, and interpretation of the antimicrobial susceptibility of all clinical isolates that incorporates rule-based classification and cluster analysis of MDROs and implements control chart analysis to facilitate outbreak detection. Methods Electronic microbiological data from a 2200-bed teaching hospital in Taiwan were classified according to predefined criteria of MDROs. The numbers of organisms, patients, and incident patients in each MDRO pattern were presented graphically to describe spatial and time information in a Web-based user interface. Hierarchical clustering with 7 upper control limits (UCL) was used to detect suspicious outbreaks. The system’s performance in outbreak detection was evaluated based on vancomycin-resistant enterococcal outbreaks determined by a hospital-wide prospective active surveillance database compiled by infection control personnel. Results The optimal UCL for MDRO outbreak detection was the upper 90% confidence interval (CI) using germ criterion with clustering (area under ROC curve (AUC) 0.93, 95% CI 0.91 to 0.95), upper 85% CI using patient criterion (AUC 0.87, 95% CI 0.80 to 0.93), and one standard deviation using incident patient criterion (AUC 0.84, 95% CI 0.75 to 0.92). The performance indicators of each UCL were statistically significantly higher with clustering than those without clustering in germ criterion (P < .001), patient criterion (P = .04), and incident patient criterion (P < .001). Conclusion This system automatically identifies MDROs and accurately detects suspicious outbreaks of MDROs based on the antimicrobial susceptibility of all clinical isolates. PMID:23195868
Controlling the last known cluster of Ebola virus disease - Liberia, January-February 2015.
Nyenswah, Tolbert; Fallah, Mosoka; Sieh, Sonpon; Kollie, Karsor; Badio, Moses; Gray, Alvin; Dilah, Priscilla; Shannon, Marnijina; Duwor, Stanley; Ihekweazu, Chikwe; Cordier-Lassalle, Thierry; Cordier-Lasalle, Thierry; Shinde, Shivam A; Hamblion, Esther; Davies-Wayne, Gloria; Ratnesh, Murugan; Dye, Christopher; Yoder, Jonathan S; McElroy, Peter; Hoots, Brooke; Christie, Athalia; Vertefeuille, John; Olsen, Sonja J; Laney, A Scott; Neal, Joyce J; Yaemsiri, Sirin; Navin, Thomas R; Coulter, Stewart; Pordell, Paran; Lo, Terrence; Kinkade, Carl; Mahoney, Frank
2015-05-15
As one of the three West African countries highly affected by the 2014-2015 Ebola virus disease (Ebola) epidemic, Liberia reported approximately 10,000 cases. The Ebola epidemic in Liberia was marked by intense urban transmission, multiple community outbreaks with source cases occurring in patients coming from the urban areas, and outbreaks in health care facilities (HCFs). This report, based on data from routine case investigations and contact tracing, describes efforts to stop the last known chain of Ebola transmission in Liberia. The index patient became ill on December 29, 2014, and the last of 21 associated cases was in a patient admitted into an Ebola treatment unit (ETU) on February 18, 2015. The chain of transmission was stopped because of early detection of new cases; identification, monitoring, and support of contacts in acceptable settings; effective triage within the health care system; and rapid isolation of symptomatic contacts. In addition, a "sector" approach, which divided Montserrado County into geographic units, facilitated the ability of response teams to rapidly respond to community needs. In the final stages of the outbreak, intensive coordination among partners and engagement of community leaders were needed to stop transmission in densely populated Montserrado County. A companion report describes the efforts to enhance infection prevention and control efforts in HCFs. After February 19, no additional clusters of Ebola cases have been detected in Liberia. On May 9, the World Health Organization declared the end of the Ebola outbreak in Liberia.
Condell, Orla; Wasunna, Christine; Kpaka, Jonathan; Zwizwai, Ruth; Nuha, Mahmood; Fallah, Mosoka; Freeman, Maxwell; Harris, Victoria; Miller, Mark; Baller, April; Massaquoi, Moses; Katawera, Victoria; Saindon, John; Bemah, Philip; Hamblion, Esther; Castle, Evelyn; Williams, Desmond; Gasasira, Alex; Nyenswah, Tolbert
2018-01-01
The 2014–16 Ebola Virus Disease (EVD) outbreak in West Africa highlighted the necessity for readily available, accurate and rapid diagnostics. The magnitude of the outbreak and the re-emergence of clusters of EVD cases following the declaration of interrupted transmission in Liberia, reinforced the need for sustained diagnostics to support surveillance and emergency preparedness. We describe implementation of the Xpert Ebola Assay, a rapid molecular diagnostic test run on the GeneXpert platform, at a mobile laboratory in Liberia and the subsequent impact on EVD outbreak response, case management and laboratory system strengthening. During the period of operation, site coordination, management and operational capacity was supported through a successful collaboration between Ministry of Health (MoH), World Health Organization (WHO) and international partners. A team of Liberian laboratory technicians were trained to conduct EVD diagnostics and the laboratory had capacity to test 64–100 blood specimens per day. Establishment of the laboratory significantly increased the daily testing capacity for EVD in Liberia, from 180 to 250 specimens at a time when the effectiveness of the surveillance system was threatened by insufficient diagnostic capacity. During the 18 months of operation, the laboratory tested a total of 9,063 blood specimens, including 21 EVD positives from six confirmed cases during two outbreaks. Following clearance of the significant backlog of untested EVD specimens in November 2015, a new cluster of EVD cases was detected at the laboratory. Collaboration between surveillance and laboratory coordination teams during this and a later outbreak in March 2016, facilitated timely and targeted response interventions. Specimens taken from cases during both outbreaks were analysed at the laboratory with results informing clinical management of patients and discharge decisions. The GeneXpert platform is easy to use, has relatively low running costs and can be integrated into other national diagnostic algorithms. The technology has on average a 2-hour sample-to-result time and allows for single specimen testing to overcome potential delays of batching. This model of a mobile laboratory equipped with Xpert Ebola test, staffed by local laboratory technicians, could serve to strengthen outbreak preparedness and response for future outbreaks of EVD in Liberia and the region. PMID:29304039
Raftery, Philomena; Condell, Orla; Wasunna, Christine; Kpaka, Jonathan; Zwizwai, Ruth; Nuha, Mahmood; Fallah, Mosoka; Freeman, Maxwell; Harris, Victoria; Miller, Mark; Baller, April; Massaquoi, Moses; Katawera, Victoria; Saindon, John; Bemah, Philip; Hamblion, Esther; Castle, Evelyn; Williams, Desmond; Gasasira, Alex; Nyenswah, Tolbert
2018-01-01
The 2014-16 Ebola Virus Disease (EVD) outbreak in West Africa highlighted the necessity for readily available, accurate and rapid diagnostics. The magnitude of the outbreak and the re-emergence of clusters of EVD cases following the declaration of interrupted transmission in Liberia, reinforced the need for sustained diagnostics to support surveillance and emergency preparedness. We describe implementation of the Xpert Ebola Assay, a rapid molecular diagnostic test run on the GeneXpert platform, at a mobile laboratory in Liberia and the subsequent impact on EVD outbreak response, case management and laboratory system strengthening. During the period of operation, site coordination, management and operational capacity was supported through a successful collaboration between Ministry of Health (MoH), World Health Organization (WHO) and international partners. A team of Liberian laboratory technicians were trained to conduct EVD diagnostics and the laboratory had capacity to test 64-100 blood specimens per day. Establishment of the laboratory significantly increased the daily testing capacity for EVD in Liberia, from 180 to 250 specimens at a time when the effectiveness of the surveillance system was threatened by insufficient diagnostic capacity. During the 18 months of operation, the laboratory tested a total of 9,063 blood specimens, including 21 EVD positives from six confirmed cases during two outbreaks. Following clearance of the significant backlog of untested EVD specimens in November 2015, a new cluster of EVD cases was detected at the laboratory. Collaboration between surveillance and laboratory coordination teams during this and a later outbreak in March 2016, facilitated timely and targeted response interventions. Specimens taken from cases during both outbreaks were analysed at the laboratory with results informing clinical management of patients and discharge decisions. The GeneXpert platform is easy to use, has relatively low running costs and can be integrated into other national diagnostic algorithms. The technology has on average a 2-hour sample-to-result time and allows for single specimen testing to overcome potential delays of batching. This model of a mobile laboratory equipped with Xpert Ebola test, staffed by local laboratory technicians, could serve to strengthen outbreak preparedness and response for future outbreaks of EVD in Liberia and the region.
Detection of Zika Virus in April 2013 Patient Samples, Rio de Janeiro, Brazil
Borges dos Santos, Maria A.; Cerbino-Neto, José; Buonora, Sibelle N.; Souza, Thiago M.L.; de Oliveira, Raquel V.C.; Vizzoni, Alexandre; Barbosa-Lima, Giselle; Vieira, Yasmine R.; Silva de Lima, Marcondes; Hökerberg, Yara H. M.
2017-01-01
We tested 210 dengue virus‒negative samples collected from febrile patients during a dengue virus type 4 outbreak in Rio de Janeiro in April 2013 and found 3 samples positive for Zika virus. Our findings support previously published entomological data suggesting Zika virus was introduced into Brazil during October 2012–May 2013. PMID:28953451
Steven C. McKelvey; William D. Smith; Frank Koch
2012-01-01
This project summary describes a probabilistic model developed with funding support from the Forest Health Monitoring Program of the Forest Service, U.S. Department of Agriculture (BaseEM Project SO-R-08-01). The model has been implemented in SODBuster, a standalone software package developed using the Java software development kit from Sun Microsystems.
Talbot, Thomas R; Schaffner, William; Bloch, Karen C; Daniels, Titus L; Miller, Randolph A
2011-01-01
Objective The authors evaluated algorithms commonly used in syndromic surveillance for use as screening tools to detect potentially clonal outbreaks for review by infection control practitioners. Design Study phase 1 applied four aberrancy detection algorithms (CUSUM, EWMA, space-time scan statistic, and WSARE) to retrospective microbiologic culture data, producing a list of past candidate outbreak clusters. In phase 2, four infectious disease physicians categorized the phase 1 algorithm-identified clusters to ascertain algorithm performance. In phase 3, project members combined the algorithms to create a unified screening system and conducted a retrospective pilot evaluation. Measurements The study calculated recall and precision for each algorithm, and created precision-recall curves for various methods of combining the algorithms into a unified screening tool. Results Individual algorithm recall and precision ranged from 0.21 to 0.31 and from 0.053 to 0.29, respectively. Few candidate outbreak clusters were identified by more than one algorithm. The best method of combining the algorithms yielded an area under the precision-recall curve of 0.553. The phase 3 combined system detected all infection control-confirmed outbreaks during the retrospective evaluation period. Limitations Lack of phase 2 reviewers' agreement indicates that subjective expert review was an imperfect gold standard. Less conservative filtering of culture results and alternate parameter selection for each algorithm might have improved algorithm performance. Conclusion Hospital outbreak detection presents different challenges than traditional syndromic surveillance. Nevertheless, algorithms developed for syndromic surveillance have potential to form the basis of a combined system that might perform clinically useful hospital outbreak screening. PMID:21606134
A framework for responding to coral disease outbreaks that facilitates adaptive management.
Beeden, Roger; Maynard, Jeffrey A; Marshall, Paul A; Heron, Scott F; Willis, Bette L
2012-01-01
Predicted increases in coral disease outbreaks associated with climate change have implications for coral reef ecosystems and the people and industries that depend on them. It is critical that coral reef managers understand these implications and have the ability to assess and reduce risk, detect and contain outbreaks, and monitor and minimise impacts. Here, we present a coral disease response framework that has four core components: (1) an early warning system, (2) a tiered impact assessment program, (3) scaled management actions and (4) a communication plan. The early warning system combines predictive tools that monitor the risk of outbreaks of temperature-dependent coral diseases with in situ observations provided by a network of observers who regularly report on coral health and reef state. Verified reports of an increase in disease prevalence trigger a tiered response of more detailed impact assessment, targeted research and/or management actions. The response is scaled to the risk posed by the outbreak, which is a function of the severity and spatial extent of the impacts. We review potential management actions to mitigate coral disease impacts and facilitate recovery, considering emerging strategies unique to coral disease and more established strategies to support reef resilience. We also describe approaches to communicating about coral disease outbreaks that will address common misperceptions and raise awareness of the coral disease threat. By adopting this framework, managers and researchers can establish a community of practice and can develop response plans for the management of coral disease outbreaks based on local needs. The collaborations between managers and researchers we suggest will enable adaptive management of disease impacts following evaluating the cost-effectiveness of emerging response actions and incrementally improving our understanding of outbreak causation.
A Framework for Responding to Coral Disease Outbreaks that Facilitates Adaptive Management
NASA Astrophysics Data System (ADS)
Beeden, Roger; Maynard, Jeffrey A.; Marshall, Paul A.; Heron, Scott F.; Willis, Bette L.
2012-01-01
Predicted increases in coral disease outbreaks associated with climate change have implications for coral reef ecosystems and the people and industries that depend on them. It is critical that coral reef managers understand these implications and have the ability to assess and reduce risk, detect and contain outbreaks, and monitor and minimise impacts. Here, we present a coral disease response framework that has four core components: (1) an early warning system, (2) a tiered impact assessment program, (3) scaled management actions and (4) a communication plan. The early warning system combines predictive tools that monitor the risk of outbreaks of temperature-dependent coral diseases with in situ observations provided by a network of observers who regularly report on coral health and reef state. Verified reports of an increase in disease prevalence trigger a tiered response of more detailed impact assessment, targeted research and/or management actions. The response is scaled to the risk posed by the outbreak, which is a function of the severity and spatial extent of the impacts. We review potential management actions to mitigate coral disease impacts and facilitate recovery, considering emerging strategies unique to coral disease and more established strategies to support reef resilience. We also describe approaches to communicating about coral disease outbreaks that will address common misperceptions and raise awareness of the coral disease threat. By adopting this framework, managers and researchers can establish a community of practice and can develop response plans for the management of coral disease outbreaks based on local needs. The collaborations between managers and researchers we suggest will enable adaptive management of disease impacts following evaluating the cost-effectiveness of emerging response actions and incrementally improving our understanding of outbreak causation.
Weterings, Veronica; Bosch, Thijs; Witteveen, Sandra; Landman, Fabian; Schouls, Leo; Kluytmans, Jan
2017-09-01
Resistance to methicillin in Staphylococcus aureus is caused primarily by the mecA gene, which is carried on a mobile genetic element, the staphylococcal cassette chromosome mec (SCC mec ). Horizontal transfer of this element is supposed to be an important factor in the emergence of new clones of methicillin-resistant Staphylococcus aureus (MRSA) but has been rarely observed in real time. In 2012, an outbreak occurred involving a health care worker (HCW) and three patients, all carrying a fusidic acid-resistant MRSA strain. The husband of the HCW was screened for MRSA carriage, but only a methicillin-susceptible S. aureus (MSSA) strain, which was also resistant to fusidic acid, was detected. Multiple-locus variable-number tandem-repeat analysis (MLVA) typing showed that both the MSSA and MRSA isolates were MT4053-MC0005. This finding led to the hypothesis that the MSSA strain acquired the SCC mec and subsequently caused an outbreak. To support this hypothesis, next-generation sequencing of the MSSA and MRSA isolates was performed. This study showed that the MSSA isolate clustered closely with the outbreak isolates based on whole-genome multilocus sequence typing and single-nucleotide polymorphism (SNP) analysis, with a genetic distance of 17 genes and 44 SNPs, respectively. Remarkably, there were relatively large differences in the mobile genetic elements in strains within and between individuals. The limited genetic distance between the MSSA and MRSA isolates in combination with a clear epidemiologic link supports the hypothesis that the MSSA isolate acquired a SCC mec and that the resulting MRSA strain caused an outbreak. Copyright © 2017 American Society for Microbiology.
Newkirk, Ryan W; Hedberg, Craig W
2012-02-01
The main objective of this study was to develop an understanding of the descriptive epidemiology of foodborne botulism in the context of outbreak detection and food defense. This study used 1993-2008 data from the Centers for Disease Control and Prevention (CDC) Annual Summaries of Notifiable Diseases, 2003-2006 data from the Bacterial Foodborne and Diarrheal Disease National Case Surveillance Annual Reports, and 1993-2008 data from the Annual Listing of Foodborne Disease Outbreaks. Published outbreak investigation reports were identified through a PubMed search of MEDLINE citations for botulism outbreaks. Fifty-eight foodborne botulism outbreaks were reported to CDC between 1993 and 2008. Four hundred sixteen foodborne botulism cases were documented; 205 (49%) were associated with outbreaks. Familial connections and co-hospitalization of initial presenting cases were common in large outbreaks (>5 cases). In these outbreaks, the time from earliest exposure to outbreak recognition varied dramatically (range, 48-216 h). The identification of epidemiologic linkages between foodborne botulism cases is a critical part of diagnostic evaluation and outbreak detection. Investigation of an intentionally contaminated food item with a long shelf life and widespread distribution may be delayed until an astute physician suspects foodborne botulism; suspicion of foodborne botulism occurs more frequently when more than one case is hospitalized concurrently. In an effort to augment national botulism surveillance and antitoxin release systems and to improve food defense and public health preparedness efforts, medical organizations and Homeland Security officials should emphasize the education and training of medical personnel to improve foodborne botulism diagnostic capabilities to recognize single foodborne botulism cases and to look for epidemiologic linkages between suspected cases.
Devising a method towards development of early warning tool for detection of malaria outbreak.
Verma, Preeti; Sarkar, Soma; Singh, Poonam; Dhiman, Ramesh C
2017-11-01
Uncertainty often arises in differentiating seasonal variation from outbreaks of malaria. The present study was aimed to generalize the theoretical structure of sine curve for detecting an outbreak so that a tool for early warning of malaria may be developed. A 'case/mean-ratio scale' system was devised for labelling the outbreak in respect of two diverse districts of Assam and Rajasthan. A curve-based method of analysis was developed for determining outbreak and using the properties of sine curve. It could be used as an early warning tool for Plasmodium falciparum malaria outbreaks. In the present method of analysis, the critical C max (peak value of sine curve) value of seasonally adjusted curve for P. falciparum malaria outbreak was 2.3 for Karbi Anglong and 2.2 for Jaisalmer districts. On case/mean-ratio scale, the C max value of malaria curve between C max and 3.5, the outbreak could be labelled as minor while >3.5 may be labelled as major. In epidemic years, with mean of case/mean ratio of ≥1.00 and root mean square (RMS) ≥1.504 of case/mean ratio, outbreaks can be predicted 1-2 months in advance. The present study showed that in P. falciparum cases in Karbi Anglong (Assam) and Jaisalmer (Rajasthan) districts, the rise in C max value of curve was always followed by rise in average/RMS or both and hence could be used as an early warning tool. The present method provides better detection of outbreaks than the conventional method of mean plus two standard deviation (mean+2 SD). The identified tools are simple and may be adopted for preparedness of malaria outbreaks.
Smolinski, Mark S.; Olsen, Jennifer M.
2017-01-01
Rapid detection, reporting, and response to an infectious disease outbreak are critical to prevent localized health events from emerging as pandemic threats. Metrics to evaluate the timeliness of these critical activities, however, are lacking. Easily understood and comparable measures for tracking progress and encouraging investment in rapid detection, reporting, and response are sorely needed. We propose that the timeliness of outbreak detection, reporting, laboratory confirmation, response, and public communication should be considered as measures for improving global health security at the national level, allowing countries to track progress over time and inform investments in disease surveillance. PMID:28384035
Dórea, Fernanda C.; McEwen, Beverly J.; McNab, W. Bruce; Sanchez, Javier; Revie, Crawford W.
2013-01-01
Background Syndromic surveillance research has focused on two main themes: the search for data sources that can provide early disease detection; and the development of efficient algorithms that can detect potential outbreak signals. Methods This work combines three algorithms that have demonstrated solid performance in detecting simulated outbreak signals of varying shapes in time series of laboratory submissions counts. These are: the Shewhart control charts designed to detect sudden spikes in counts; the EWMA control charts developed to detect slow increasing outbreaks; and the Holt-Winters exponential smoothing, which can explicitly account for temporal effects in the data stream monitored. A scoring system to detect and report alarms using these algorithms in a complementary way is proposed. Results The use of multiple algorithms in parallel resulted in increased system sensitivity. Specificity was decreased in simulated data, but the number of false alarms per year when the approach was applied to real data was considered manageable (between 1 and 3 per year for each of ten syndromic groups monitored). The automated implementation of this approach, including a method for on-line filtering of potential outbreak signals is described. Conclusion The developed system provides high sensitivity for detection of potential outbreak signals while also providing robustness and flexibility in establishing what signals constitute an alarm. This flexibility allows an analyst to customize the system for different syndromes. PMID:24349216
Dórea, Fernanda C; McEwen, Beverly J; McNab, W Bruce; Sanchez, Javier; Revie, Crawford W
2013-01-01
Syndromic surveillance research has focused on two main themes: the search for data sources that can provide early disease detection; and the development of efficient algorithms that can detect potential outbreak signals. This work combines three algorithms that have demonstrated solid performance in detecting simulated outbreak signals of varying shapes in time series of laboratory submissions counts. These are: the Shewhart control charts designed to detect sudden spikes in counts; the EWMA control charts developed to detect slow increasing outbreaks; and the Holt-Winters exponential smoothing, which can explicitly account for temporal effects in the data stream monitored. A scoring system to detect and report alarms using these algorithms in a complementary way is proposed. The use of multiple algorithms in parallel resulted in increased system sensitivity. Specificity was decreased in simulated data, but the number of false alarms per year when the approach was applied to real data was considered manageable (between 1 and 3 per year for each of ten syndromic groups monitored). The automated implementation of this approach, including a method for on-line filtering of potential outbreak signals is described. The developed system provides high sensitivity for detection of potential outbreak signals while also providing robustness and flexibility in establishing what signals constitute an alarm. This flexibility allows an analyst to customize the system for different syndromes.
Rosin, P; Niskanen, T; Palm, D; Struelens, M; Takkinen, J
2013-06-20
A hybrid strain of enteroaggregative and Shiga toxin 2-producing Escherichia coli (EAEC-STEC) serotype O104:H4 strain caused a large outbreak of haemolytic uraemic syndrome and bloody diarrhoea in 2011 in Europe. Two surveys were performed in the European Union (EU) and European Economic Area (EEA) countries to assess their laboratory capabilities to detect and characterise this previously uncommon STEC strain. Prior to the outbreak, 11 of the 32 countries in this survey had capacity at national reference laboratory (NRL) level for epidemic case confirmation according to the EU definition. During the outbreak, at primary diagnostic level, nine countries reported that clinical microbiology laboratories routinely used Shiga toxin detection assays suitable for diagnosis of infections with EAEC-STEC O104:H4, while 14 countries had NRL capacity to confirm epidemic cases. Six months after the outbreak, 22 countries reported NRL capacity to confirm such cases following initiatives taken by NRLs and the European Centre for Disease Prevention and Control (ECDC) Food- and Waterborne Disease and Zoonoses laboratory network. These data highlight the challenge of detection and confirmation of epidemic infections caused by atypical STEC strains and the benefits of coordinated EU laboratory networks to strengthen capabilities in response to a major outbreak.
de Roda Husman, Ana Maria; Lodder-Verschoor, Froukje; van den Berg, Harold H J L; Le Guyader, Françoise S; van Pelt, Hilde; van der Poel, Wim H M; Rutjes, Saskia A
2007-04-01
Detection of pathogenic viruses in oysters implicated in gastroenteritis outbreaks is often hampered by time-consuming, specialist virus extraction methods. Five virus RNA extraction methods were evaluated with respect to performance characteristics and sensitivity on artificially contaminated oyster digestive glands. The two most promising procedures were further evaluated on bioaccumulated and naturally contaminated oysters. The most efficient method was used to trace the source in an outbreak situation. Out of five RNA extraction protocols, PEG precipitation and the RNeasy Kit performed best with norovirus genogroup III-spiked digestive glands. Analyzing 24-h bioaccumulated oysters revealed a slightly better sensitivity with PEG precipitation, but the RNeasy Kit was less prone to concentrate inhibitors. The latter procedure demonstrated the presence of human noroviruses in naturally contaminated oysters and oysters implicated in an outbreak. In this outbreak, in four out of nine individually analyzed digestive glands, norovirus was detected. In one of the oysters and in one of the fecal samples of the clinical cases, identical norovirus strains were detected. A standard and rapid virus extraction method using the RNeasy Kit appeared to be most useful in tracing shellfish as the source in gastroenteritis outbreaks, and to be able to make effective and timely risk management decisions.
Mouchtouri, Varvara A; Verykouki, Eleni; Zamfir, Dumitru; Hadjipetris, Christos; Lewis, Hannah C; Hadjichristodoulou, Christos
2017-01-01
When an increased number of acute gastroenteritis (AG) cases is detected among tourists staying at the same accommodation, outbreak management plans must be activated in a timely manner to prevent large outbreaks. Syndromic surveillance data collected between 1 January 2010 and 31 December 2013 by five seagoing cruise ships were analysed to identify attack rate thresholds for early outbreak detection. The overall incidence rate of AG was 2.81 cases per 10,000 traveller-days (95% confidence interval (CI): 0.00–17.60), while the attack rate was 19.37 cases per 10,000 travellers (95% CI: 0.00–127.69). The probability of an outbreak occurring was 11% if 4 per 1,000 passengers reported symptoms within the first 2 days of the voyage, and this increased to 23 % if 5 per 1,000 passengers reported such within the first 3 days. The risk ratio (RR) for outbreak occurrence was 2.35, 5.66 and 8.63 for 1, 2 and 3 days’ delay of symptoms reporting respectively, suggesting a dose–response relationship. Shipping companies’ policies and health authorities’ efforts may consider these thresholds for initiating outbreak response measures based on the number of cases according to day of cruise. Efforts should focus on ensuring travellers report symptoms immediately and comply with isolation measures. PMID:29162205
Daily Reportable Disease Spatiotemporal Cluster Detection, New York City, New York, USA, 2014-2015.
Greene, Sharon K; Peterson, Eric R; Kapell, Deborah; Fine, Annie D; Kulldorff, Martin
2016-10-01
Each day, the New York City Department of Health and Mental Hygiene uses the free SaTScan software to apply prospective space-time permutation scan statistics to strengthen early outbreak detection for 35 reportable diseases. This method prompted early detection of outbreaks of community-acquired legionellosis and shigellosis.
The 2012 Madeira dengue outbreak: epidemiological determinants and future epidemic potential.
Lourenço, José; Recker, Mario
2014-08-01
Dengue, a vector-borne viral disease of increasing global importance, is classically associated with tropical and sub-tropical regions around the world. Urbanisation, globalisation and climate trends, however, are facilitating the geographic spread of its mosquito vectors, thereby increasing the risk of the virus establishing itself in previously unaffected areas and causing large-scale epidemics. On 3 October 2012, two autochthonous dengue infections were reported within the Autonomous Region of Madeira, Portugal. During the following seven months, this first 'European' dengue outbreak caused more than 2000 local cases and 81 exported cases to mainland Europe. Here, using an ento-epidemiological mathematical framework, we estimate that the introduction of dengue to Madeira occurred around a month before the first official cases, during the period of maximum influx of airline travel, and that the naturally declining temperatures of autumn were the determining factor for the outbreak's demise in early December 2012. Using key estimates, together with local climate data, we further propose that there is little support for dengue endemicity on this island, but a high potential for future epidemic outbreaks when seeded between May and August-a period when detection of imported cases is crucial for Madeira's public health planning.
The 2012 Madeira Dengue Outbreak: Epidemiological Determinants and Future Epidemic Potential
Lourenço, José; Recker, Mario
2014-01-01
Dengue, a vector-borne viral disease of increasing global importance, is classically associated with tropical and sub-tropical regions around the world. Urbanisation, globalisation and climate trends, however, are facilitating the geographic spread of its mosquito vectors, thereby increasing the risk of the virus establishing itself in previously unaffected areas and causing large-scale epidemics. On 3 October 2012, two autochthonous dengue infections were reported within the Autonomous Region of Madeira, Portugal. During the following seven months, this first ‘European’ dengue outbreak caused more than 2000 local cases and 81 exported cases to mainland Europe. Here, using an ento-epidemiological mathematical framework, we estimate that the introduction of dengue to Madeira occurred around a month before the first official cases, during the period of maximum influx of airline travel, and that the naturally declining temperatures of autumn were the determining factor for the outbreak's demise in early December 2012. Using key estimates, together with local climate data, we further propose that there is little support for dengue endemicity on this island, but a high potential for future epidemic outbreaks when seeded between May and August—a period when detection of imported cases is crucial for Madeira's public health planning. PMID:25144749
Full genome analysis of enterovirus D-68 strains circulating in Alberta, Canada.
Pabbaraju, Kanti; Wong, Sallene; Drews, Steven J; Tipples, Graham; Tellier, Raymond
2016-07-01
A widespread outbreak of enterovirus (EV)-D68 that started in the summer of 2014 has been reported in the USA and Canada. During the course of this outbreak, EV-D68 was identified as a possible cause of acute, unexplained severe respiratory illness and a temporal association was observed between acute flaccid paralysis with anterior myelitis and EV-D68 detection in the upper respiratory tract. In this study, four nasopharyngeal samples collected from patients in Alberta, Canada with a laboratory diagnosis of EV-D68 were used to determine the near full-length genome sequence directly from the specimens. Phylogenetic analysis was performed to study the genotypes and pathogenesis of the circulating strains. Our results support the contention that mutations in the VP1 gene and other regions of the genome causing altered antigenicity, as well as lack of immunity in the younger population, may be responsible for the increased severe respiratory disease outbreaks of EV-D68 worldwide. © 2015 Wiley Periodicals, Inc.
Khare, Shashi; Agarwal, Ramesh; Singh, Ranjana; Lal, Shiv
2006-07-01
The current outbreak of H5N 1 avian influenza affecting an unprecedented number of countries is a cause of concern worldwide. As on 26th June, 2006 outbreaks in poultry or wild birds have been reported from 54 countries. In India the first outbreak of avian influenza virus Awas reported in Navapur district in Maharashtra in February 2006 followed by detection of H5N1 in a neighbouring district of Gujarat. No case of human infection has yet been reported in India. Avian influenza virus belongs to influenza type A which is a part of family orthomyxoviridae. Transmission occurs by direct or indirect contact. Clinical symptoms on human is of typical influenza like. Laboratory investigations involves a number of tests confirming diagnosis of avian influenza. The treatment includes general supportive and antiviral therapy with oseltamivir. Prevention and control strategies can held to minimise the public health risk to highly pathogenic avian influenza. There are some dos and don'ts for the community which should be strictly followed.
Nguyen-Hieu, Tung; Aboudharam, Gérard; Signoli, Michel; Rigeade, Catherine; Drancourt, Michel; Raoult, Didier
2010-10-27
The new field of paleomicrobiology allows past outbreaks to be identified by testing dental pulp of human remains with PCR. We identified a mass grave in Douai, France dating from the early XVIII(th) century. This city was besieged during the European war of Spanish succession. We tested dental pulp from 1192 teeth (including 40 from Douai) by quantitative PCR (qPCR) for R. prowazekii and B. quintana. We also used ultra-sensitive suicide PCR to detect R. prowazekii and genotyped positive samples. In the Douai remains, we identified one case of B. quintana infection (by qPCR) and R. prowazekii (by suicide PCR) in 6/21 individuals (29%). The R. prowazekii was genotype B, a genotype previously found in a Spanish isolate obtained in the first part of the XX(th) century. Louse-borne outbreaks were raging during the XVIII(th) century; our results support the hypothesis that typhus was imported into Europe by Spanish soldiers from America.
Nguyen-Hieu, Tung; Aboudharam, Gérard; Signoli, Michel; Rigeade, Catherine; Drancourt, Michel; Raoult, Didier
2010-01-01
Background The new field of paleomicrobiology allows past outbreaks to be identified by testing dental pulp of human remains with PCR. Methods We identified a mass grave in Douai, France dating from the early XVIIIth century. This city was besieged during the European war of Spanish succession. We tested dental pulp from 1192 teeth (including 40 from Douai) by quantitative PCR (qPCR) for R. prowazekii and B. quintana. We also used ultra-sensitive suicide PCR to detect R. prowazekii and genotyped positive samples. Results and Discussion In the Douai remains, we identified one case of B. quintana infection (by qPCR) and R. prowazekii (by suicide PCR) in 6/21 individuals (29%). The R. prowazekii was genotype B, a genotype previously found in a Spanish isolate obtained in the first part of the XXth century. Conclusion Louse-borne outbreaks were raging during the XVIIIth century; our results support the hypothesis that typhus was imported into Europe by Spanish soldiers from America. PMID:21060879
Molecular analysis of an oyster-related norovirus outbreak.
Nenonen, Nancy P; Hannoun, Charles; Olsson, Margareta B; Bergström, Tomas
2009-06-01
Contaminated raw oysters were implicated in a severe outbreak of norovirus (NoV) gastroenteritis affecting 30 restaurant guests. To define the outbreak source by using molecular methods to characterize NoV strains detected in patient and oyster samples. Molecular epidemiological studies based on nucleotide sequencing and phylogenetic analyses of patient and oyster NoV strains, and comparison to background dataset. NoV genotype (G) I.1 was detected in the one patient stool analyzed by in-house TaqMan real time RT-PCR and classical nested RT-PCR targeting NoV RNA-dependent polymerase (RdRp, 285 nt), and by nested RT-PCR targeting RdRp-capsid-poly(A)-3' (3085 nt). Patient strain showed >or=99% similarity (285 nt) with three NoV strains detected in two of five oysters examined by classical nested RT-PCR (RdRp). A third oyster tested positive for NoV GII.3. Phylogenetic analysis showed clustering of patient and oyster strains related to this outbreak with GI.1 strains from previous local outbreaks, and mussel studies. Sequence data revealed >or=99% similarity (285 nt) between NoV GI.1 strains detected in patient stool and suspect oysters, linking the contaminated oysters to the outbreak. Identification of human NoV GI and GII strains in oysters indicated contamination of human fecal origin, presumably from inappropriate storage in the harbor. Comparative long-fragment analysis of the patient strain revealed 99% similarity (3085 nt) with NoV GI.1 strains detected in previous outbreaks and environmental mussel studies from West Sweden, 87% with M87661 (Norwalk68) and 96% with L23828 (SRSV-KY-89/89/J). These results indicated considerable genomic stability of NoV GI.1 strains over time.
Emergence of new norovirus variants on spring cruise ships and prediction of winter epidemics.
Verhoef, Linda; Depoortere, Evelyn; Boxman, Ingeborg; Duizer, Erwin; van Duynhoven, Yvonne; Harris, John; Johnsen, Christina; Kroneman, Annelies; Le Guyader, Soizick; Lim, Wilina; Maunula, Leena; Meldal, Hege; Ratcliff, Rod; Reuter, Gábor; Schreier, Eckart; Siebenga, Joukje; Vainio, Kirsti; Varela, Carmen; Vennema, Harry; Koopmans, Marion
2008-02-01
In June 2006, reported outbreaks of norovirus on cruise ships suddenly increased; 43 outbreaks occurred on 13 vessels. All outbreaks investigated manifested person-to-person transmission. Detection of a point source was impossible because of limited investigation of initial outbreaks and data sharing. The most probable explanation for these outbreaks is increased norovirus activity in the community, which coincided with the emergence of 2 new GGII.4 variant strains in Europe and the Pacific. As in 2002, a new GGII.4 variant detected in the spring and summer corresponded with high norovirus activity in the subsequent winter. Because outbreaks on cruise ships are likely to occur when new variants circulate, an active reporting system could function as an early warning system. Internationally accepted guidelines are needed for reporting, investigating, and controlling norovirus illness on cruise ships in Europe.
Emergence of New Norovirus Variants on Spring Cruise Ships and Prediction of Winter Epidemics
Depoortere, Evelyn; Boxman, Ingeborg; Duizer, Erwin; van Duynhoven, Yvonne; Harris, John; Johnsen, Christina; Kroneman, Annelies; Le Guyader, Soizick; Lim, Wilina; Maunula, Leena; Meldal, Hege; Ratcliff, Rod; Reuter, Gábor; Schreier, Eckart; Siebenga, Joukje; Vainio, Kirsti; Varela, Carmen; Vennema, Harry; Koopmans, Marion
2008-01-01
In June 2006, reported outbreaks of norovirus on cruise ships suddenly increased; 43 outbreaks occurred on 13 vessels. All outbreaks investigated manifested person-to-person transmission. Detection of a point source was impossible because of limited investigation of initial outbreaks and data sharing. The most probable explanation for these outbreaks is increased norovirus activity in the community, which coincided with the emergence of 2 new GGII.4 variant strains in Europe and the Pacific. As in 2002, a new GGII.4 variant detected in the spring and summer corresponded with high norovirus activity in the subsequent winter. Because outbreaks on cruise ships are likely to occur when new variants circulate, an active reporting system could function as an early warning system. Internationally accepted guidelines are needed for reporting, investigating, and controlling norovirus illness on cruise ships in Europe. PMID:18258116
Jackson, Brendan R.; Tarr, Cheryl; Strain, Errol; Jackson, Kelly A.; Conrad, Amanda; Carleton, Heather; Katz, Lee S.; Stroika, Steven; Gould, L. Hannah; Mody, Rajal K.; Silk, Benjamin J.; Beal, Jennifer; Chen, Yi; Timme, Ruth; Doyle, Matthew; Fields, Angela; Wise, Matthew; Tillman, Glenn; Defibaugh-Chavez, Stephanie; Kucerova, Zuzana; Sabol, Ashley; Roache, Katie; Trees, Eija; Simmons, Mustafa; Wasilenko, Jamie; Kubota, Kristy; Pouseele, Hannes; Klimke, William; Besser, John; Brown, Eric; Allard, Marc; Gerner-Smidt, Peter
2016-01-01
Listeria monocytogenes (Lm) causes severe foodborne illness (listeriosis). Previous molecular subtyping methods, such as pulsed-field gel electrophoresis (PFGE), were critical in detecting outbreaks that led to food safety improvements and declining incidence, but PFGE provides limited genetic resolution. A multiagency collaboration began performing real-time, whole-genome sequencing (WGS) on all US Lm isolates from patients, food, and the environment in September 2013, posting sequencing data into a public repository. Compared with the year before the project began, WGS, combined with epidemiologic and product trace-back data, detected more listeriosis clusters and solved more outbreaks (2 outbreaks in pre-WGS year, 5 in WGS year 1, and 9 in year 2). Whole-genome multilocus sequence typing and single nucleotide polymorphism analyses provided equivalent phylogenetic relationships relevant to investigations; results were most useful when interpreted in context of epidemiological data. WGS has transformed listeriosis outbreak surveillance and is being implemented for other foodborne pathogens. PMID:27090985
Liu, Li-Juan; Liu, Wei; Liu, Yun-Xi; Xiao, Hong-Jv; Jia, Ning; Liu, Gang; Tong, Yi-Gang; Cao, Wu-Chun
2010-01-01
To elucidate the importance of the norovirus and other enteric viruses, and the difference of the genetic relatedness on norovirus between the outbreak and sporadic cases, a total of 557 stool samples, consisting of 503 sporadic cases and 54 samples of 4 outbreaks were collected and tested for norovirus and other enteric viruses in Beijing, China, July 2007–June 2008. The data showed norovirus, rotavirus, astrovirus, and sapovirus, were detected in 26.6%, 6.1%, 1.8%, and 0.5%, respectively. Norovirus was detected almost throughout the surveillance period, norovirus co-infecting with rotavirus, astrovirus, and sapovirus, respectively, were identified both in outbreak and the sporadic cases. GII.4/2006 was identified as the predominant strain circulating both in outbreak and sporadic cases. The results showed that norovirus was rather the important agent than other enteric viruses affected adults with acute gastroenteritis; no significant genetic relatedness of the dominant strains was found between the outbreak and sporadic cases. PMID:20348525
A concept for routine emergency-care data-based syndromic surveillance in Europe.
Ziemann, A; Rosenkötter, N; Garcia-Castrillo Riesgo, L; Schrell, S; Kauhl, B; Vergeiner, G; Fischer, M; Lippert, F K; Krämer, A; Brand, H; Krafft, T
2014-11-01
We developed a syndromic surveillance (SyS) concept using emergency dispatch, ambulance and emergency-department data from different European countries. Based on an inventory of sub-national emergency data availability in 12 countries, we propose framework definitions for specific syndromes and a SyS system design. We tested the concept by retrospectively applying cumulative sum and spatio-temporal cluster analyses for the detection of local gastrointestinal outbreaks in four countries and comparing the results with notifiable disease reporting. Routine emergency data was available daily and electronically in 11 regions, following a common structure. We identified two gastrointestinal outbreaks in two countries; one was confirmed as a norovirus outbreak. We detected 1/147 notified outbreaks. Emergency-care data-based SyS can supplement local surveillance with near real-time information on gastrointestinal patients, especially in special circumstances, e.g. foreign tourists. It most likely cannot detect the majority of local gastrointestinal outbreaks with few, mild or dispersed cases.
METHODS FOR DETECTION OF CRYPTOSPORIDIUM SP. AND GIARDIA SP.
There have been several waterborne outbreaks of giardiasis caused by infection with Giardia lamblia, and cryptosporidiosis, caused by infection with Cryptosporidium parvum. These outbreaks have created a need to detect these organisms in source and finished drinking water. The pr...
A flexibly shaped space-time scan statistic for disease outbreak detection and monitoring.
Takahashi, Kunihiko; Kulldorff, Martin; Tango, Toshiro; Yih, Katherine
2008-04-11
Early detection of disease outbreaks enables public health officials to implement disease control and prevention measures at the earliest possible time. A time periodic geographical disease surveillance system based on a cylindrical space-time scan statistic has been used extensively for disease surveillance along with the SaTScan software. In the purely spatial setting, many different methods have been proposed to detect spatial disease clusters. In particular, some spatial scan statistics are aimed at detecting irregularly shaped clusters which may not be detected by the circular spatial scan statistic. Based on the flexible purely spatial scan statistic, we propose a flexibly shaped space-time scan statistic for early detection of disease outbreaks. The performance of the proposed space-time scan statistic is compared with that of the cylindrical scan statistic using benchmark data. In order to compare their performances, we have developed a space-time power distribution by extending the purely spatial bivariate power distribution. Daily syndromic surveillance data in Massachusetts, USA, are used to illustrate the proposed test statistic. The flexible space-time scan statistic is well suited for detecting and monitoring disease outbreaks in irregularly shaped areas.
Prevalence of small round structured virus infections in acute gastroenteritis outbreaks in Tokyo.
Sekine, S; Okada, S; Hayashi, Y; Ando, T; Terayama, T; Yabuuchi, K; Miki, T; Ohashi, M
1989-01-01
During the three-year period from 1984 to 1987, 506 acute gastroenteritis outbreaks involving 14,383 patients were reported to the Bureau of Public Health, Tokyo Metropolitan Government. Eighty (4,324 patients) of 150 outbreaks (4,860 patients) from which etiologic agents were not identified were subjected to virological investigation. Spherical particles of 28-32 nm in diameter with capsomere-like structures on the surface were detected in patients' stool specimens. Buoyant density of the particles appeared to be 1.36 to 1.40 g/ml in CsCl. Seroconversion to the particles was observed in patients by immune electron microscopy. From these observations, we concluded that the detected particles were members of small round structured virus (SRSV), and that they were implicated in the etiologically ill-defined outbreaks encountered. Prevalence of SRSV infections in these outbreaks was examined by electron microscopy. SRSV was positive in 83.8% of the outbreaks, and 96.4% of the cases. SRSV-positive outbreaks usually occurred during winter in contrast to bacterial outbreaks which often occurred in the summer season. Of 80 outbreaks examined, 53 were associated with the ingestion of oysters, and the remaining 27 mostly with food other than oysters. Oyster-associated outbreaks usually occurred on a small scale, while unassociated ones on diverse scales ranged from family clusters to large outbreaks.
González, Estela; Álvarez, Ana; Ruiz, Sonia; Molina, Ricardo; Jiménez, Maribel
2017-07-01
Since 2010 a human leishmaniasis outbreak has been notified in southwestern Madrid region that still remains active. Entomological surveys have been carried out in the affected area in order to obtain information about species diversity, distribution, and density of sand flies. Moreover, molecular identification of blood meal preferences of sand flies and molecular detection of Leishmania infantum has been performed. In this work, we optimized a real time PCR assay in order to determine parasite loads in unfed and blood-fed Phlebotomus perniciosus female sand flies caught in the focus area. Results showed elevated parasite loads in nearly 70% of the studied positive sand flies. Furthermore, significantly higher parasite loads were observed in females without blood in their guts. In conclusion, high L. infantum loads found in P. perniciosus sand flies from the Madrid focus support the exceptional characteristics of this outbreak. Copyright © 2017 Elsevier B.V. All rights reserved.
Germinario, Cinzia; Caprioli, Alfredo; Giordano, Mario; Chironna, Maria; Gallone, Maria Serena; Tafuri, Silvio; Minelli, Fabio; Maugliani, Antonella; Michelacci, Valeria; Santangelo, Luisa; Mongelli, Onofrio; Montagna, Cosimo; Scavia, Gaia
2016-01-01
In summer 2013, an excess of paediatric cases of haemolytic uraemic syndrome (HUS) in a southern region of Italy prompted the investigation of a community-wide outbreak of Shiga toxin 2-producing Escherichia coli (STEC) O26:H11 infections. Case finding was based on testing patients with HUS or bloody diarrhoea for STEC infection by microbiological and serological methods. A case–control study was conducted to identify the source of the outbreak. STEC O26 infection was identified in 20 children (median age 17 months) with HUS, two of whom reported severe neurological sequelae. No cases in adults were detected. Molecular typing showed that two distinct STEC O26:H11 strains were involved. The case–control study showed an association between STEC O26 infection and consumption of dairy products from two local plants, but not with specific ready-to-eat products. E.coli O26:H11 strains lacking the stx genes were isolated from bulk milk and curd samples, but their PFGE profiles did not match those of the outbreak isolates. This outbreak supports the view that infections with Stx2-producing E. coli O26 in children have a high probability of progressing to HUS and represent an emerging public health problem in Europe. PMID:27684204
Germinario, Cinzia; Caprioli, Alfredo; Giordano, Mario; Chironna, Maria; Gallone, Maria Serena; Tafuri, Silvio; Minelli, Fabio; Maugliani, Antonella; Michelacci, Valeria; Santangelo, Luisa; Mongelli, Onofrio; Montagna, Cosimo; Scavia, Gaia
2016-09-22
In summer 2013, an excess of paediatric cases of haemolytic uraemic syndrome (HUS) in a southern region of Italy prompted the investigation of a community-wide outbreak of Shiga toxin 2-producing Escherichia coli (STEC) O26:H11 infections. Case finding was based on testing patients with HUS or bloody diarrhoea for STEC infection by microbiological and serological methods. A case-control study was conducted to identify the source of the outbreak. STEC O26 infection was identified in 20 children (median age 17 months) with HUS, two of whom reported severe neurological sequelae. No cases in adults were detected. Molecular typing showed that two distinct STEC O26:H11 strains were involved. The case-control study showed an association between STEC O26 infection and consumption of dairy products from two local plants, but not with specific ready-to-eat products. E.coli O26:H11 strains lacking the stx genes were isolated from bulk milk and curd samples, but their PFGE profiles did not match those of the outbreak isolates. This outbreak supports the view that infections with Stx2-producing E. coli O26 in children have a high probability of progressing to HUS and represent an emerging public health problem in Europe. This article is copyright of The Authors, 2016.
The role of the Biological Weapons Convention in disease surveillance and response.
Enemark, Christian
2010-11-01
This article assesses the role and significance of the Biological Weapons Convention (BWC) with respect to infectious disease surveillance and response to outbreaks. Increasingly, the BWC is being used as a platform for addressing infectious disease threats arising naturally as well as traditional concerns about malicious dissemination of pathogenic microorganisms. The latter have long had a place on the security agenda, but natural disease outbreaks too are now being partially 'securitized' through the use of the BWC as a forum for exchanging information and ideas on disease surveillance and response. The article focuses on two prominent issues discussed at recent meetings of BWC member states: enhancing capacity for disease surveillance and response; and responding to allegations of biological weapons use and investigating outbreaks deemed suspicious. It concludes, firstly, that the BWC supports the efforts of international health organizations to enhance disease surveillance and response capacity worldwide. And secondly, that the BWC, rather than the World Health Organization (WHO), is the appropriate institution to deal with biological weapons allegations and investigations of suspicious outbreaks. The overall message is that securitization in the health sphere cuts both ways. Adding a security dimension (BW) alongside the task of detecting and responding to naturally occurring disease outbreaks is beneficial, but requiring a non-security organization (the WHO) to assume a security role would be counterproductive.
[The EHEC O104:H4 outbreak in Germany 2011 - lessons learned?!].
Rissland, J; Kielstein, J T; Stark, K; Wichmann-Schauer, H; Stümpel, F; Pulz, M
2013-04-01
The EHEC O104:H4 outbreak 2011 in Germany provided numerous insights into the recognition and control of such epidemic situations. Food-borne outbreaks and their related dynamics may lead to a critical burden of disease and an eventual capacity overload of the medical care system. Possible difficulties in the microbiological diagnostics of new or significantly altered infectious agents may result in a delayed detection of the outbreak as well as the launching of interventional measures. Besides an early notification of the local public health office by the affected institutions, in which a complete electronic procedure and additional sentinel or surveillance instruments (e. g., in emergency departments of hospitals) may be of great help, an interdisciplinary cooperation of the local public health and food safety agencies is the key to an effective outbreak control. Corresponding organizations on the state and federal level should support the investigation process by microbiological diagnostics and advanced epidemiological analysis as well as examination of the food chains. Finally, successful crisis communication relies on "speaking with one voice" (not necessarily one person). Immediate, transparent, appropriate and honest information of the general public concerning the reasons, consequences and (counter-) measures of a crisis are the best means to keep the trust of the population and to counteract the otherwise inevitable speculations. © Georg Thieme Verlag KG Stuttgart · New York.
Schimmer, Barbara; Ter Schegget, Ronald; Wegdam, Marjolijn; Züchner, Lothar; de Bruin, Arnout; Schneeberger, Peter M; Veenstra, Thijs; Vellema, Piet; van der Hoek, Wim
2010-03-16
A Q-fever outbreak occurred in an urban area in the south of the Netherlands in May 2008. The distribution and timing of cases suggested a common source. We studied the spatial relationship between the residence locations of human cases and nearby small ruminant farms, of which one dairy goat farm had experienced abortions due to Q-fever since mid April 2008. A generic geographic information system (GIS) was used to develop a method for source detection in the still evolving major epidemic of Q-fever in the Netherlands. All notified Q-fever cases in the area were interviewed. Postal codes of cases and of small ruminant farms (size >40 animals) located within 5 kilometres of the cluster area were geo-referenced as point locations in a GIS-model. For each farm, attack rates and relative risks were calculated for 5 concentric zones adding 1 kilometre at a time, using the 5-10 kilometres zone as reference. These data were linked to the results of veterinary investigations. Persons living within 2 kilometres of an affected dairy goat farm (>400 animals) had a much higher risk for Q-fever than those living more than 5 kilometres away (Relative risk 31.1 [95% CI 16.4-59.1]). The study supported the hypothesis that a single dairy goat farm was the source of the human outbreak. GIS-based attack rate analysis is a promising tool for source detection in outbreaks of human Q-fever.
Haynes, Kyle J; Allstadt, Andrew J; Klimetzek, Dietrich
2014-06-01
To identify general patterns in the effects of climate change on the outbreak dynamics of forest-defoliating insect species, we examined a 212-year record (1800-2011) of outbreaks of five pine-defoliating species (Bupalus piniarius, Panolis flammea, Lymantria monacha, Dendrolimus pini, and Diprion pini) in Bavaria, Germany for the evidence of climate-driven changes in the severity, cyclicity, and frequency of outbreaks. We also accounted for historical changes in forestry practices and examined effects of past insecticide use to suppress outbreaks. Analysis of relationships between severity or occurrence of outbreaks and detrended measures of temperature and precipitation revealed a mixture of positive and negative relationships between temperature and outbreak activity. Two moth species (P. flammea and Dendrolimus pini) exhibited lower outbreak activity following years or decades of unusually warm temperatures, whereas a sawfly (Diprion pini), for which voltinism is influenced by temperature, displayed increased outbreak occurrence in years of high summer temperatures. We detected only one apparent effect of precipitation, which showed Dendrolimus pini outbreaks tending to follow drought. Wavelet analysis of outbreak time series suggested climate change may be associated with collapse of L. monacha and Dendrolimus pini outbreak cycles (loss of cyclicity and discontinuation of outbreaks, respectively), but high-frequency cycles for B. piniarius and P. flammea in the late 1900s. Regional outbreak severity was generally not related to past suppression efforts (area treated with insecticides). Recent shifts in forestry practices affecting tree species composition roughly coincided with high-frequency outbreak cycles in B. piniarius and P. flammea but are unlikely to explain the detected relationships between climate and outbreak severity or collapses of outbreak cycles. Our results highlight both individualistic responses of different pine-defoliating species to climate changes and some patterns that are consistent across defoliator species in this and other forest systems, including collapsing of population cycles. © 2014 John Wiley & Sons Ltd.
CASTILLA, J.; BARRICARTE, A.; ALDAZ, J.; GARCÍA CENOZ, M.; FERRER, T.; PELAZ, C.; PINEDA, S.; BALADRÓN, B.; MARTÍN, I.; GOÑI, B.; ARATAJO, P.; CHAMORRO, J.; LAMEIRO, F.; TORROBA, L.; DORRONSORO, I.; MARTÍNEZ-ARTOLA, V.; ESPARZA, M. J.; GASTAMINZA, M. A.; FRAILE, P.; ALDAZ, P.
2008-01-01
SUMMARY An outbreak of Legionnaire's disease was detected in Pamplona, Spain, on 1 June 2006. Patients with pneumonia were tested to detect Legionella pneumophila antigen in urine (Binax Now; Binax Inc., Scarborough, ME, USA), and all 146 confirmed cases were interviewed. The outbreak was related to district 2 (22 012 inhabitants), where 45% of the cases lived and 50% had visited; 5% lived in neighbouring districts. The highest incidence was found in the resident population of district 2 (3/1000 inhabitants), section 2 (14/1000). All 31 cooling towers of district 2 were analysed. L. pneumophila antigen (Binax Now) was detected in four towers, which were closed on 2 June. Only the strain isolated in a tower situated in section 2 of district 2 matched all five clinical isolates, as assessed by mAb and two genotyping methods, AFLP and PFGE. Eight days after closing the towers, new cases ceased appearing. Early detection and rapid coordinated medical and environmental actions permitted immediate control of the outbreak and probably contributed to the null case fatality. PMID:17662166
Castilla, J; Barricarte, A; Aldaz, J; García Cenoz, M; Ferrer, T; Pelaz, C; Pineda, S; Baladrón, B; Martín, I; Goñi, B; Aratajo, P; Chamorro, J; Lameiro, F; Torroba, L; Dorronsoro, I; Martínez-Artola, V; Esparza, M J; Gastaminza, M A; Fraile, P; Aldaz, P
2008-06-01
An outbreak of Legionnaire's disease was detected in Pamplona, Spain, on 1 June 2006. Patients with pneumonia were tested to detect Legionella pneumophila antigen in urine (Binax Now; Binax Inc., Scarborough, ME, USA), and all 146 confirmed cases were interviewed. The outbreak was related to district 2 (22 012 inhabitants), where 45% of the cases lived and 50% had visited; 5% lived in neighbouring districts. The highest incidence was found in the resident population of district 2 (3/1000 inhabitants), section 2 (14/1000). All 31 cooling towers of district 2 were analysed. L. pneumophila antigen (Binax Now) was detected in four towers, which were closed on 2 June. Only the strain isolated in a tower situated in section 2 of district 2 matched all five clinical isolates, as assessed by mAb and two genotyping methods, AFLP and PFGE. Eight days after closing the towers, new cases ceased appearing. Early detection and rapid coordinated medical and environmental actions permitted immediate control of the outbreak and probably contributed to the null case fatality.
TESTING METHODS FOR DETECTION OF CRYPTOSPORIDIUM SPP. IN WATER SAMPLES
A large waterborne outbreak of cryptosporidiosis in Milwaukee, Wisconsin, U.S.A. in 1993 prompted a search for ways to prevent large-scale waterborne outbreaks of protozoan parasitoses. Methods for detecting Cryptosporidium parvum play an integral role in strategies that lead to...
Gallimore, C. I.; Pipkin, C.; Shrimpton, H.; Green, A. D.; Pickford, Y.; McCartney, C.; Sutherland, G.; Brown, D. W. G.; Gray, J. J.
2005-01-01
An outbreak of acute gastroenteritis of suspected viral aetiology occurred in April 2003 in the British Royal Fleet Auxiliary ship (RFA) Argus deployed in the Northern Arabian Gulf. There were 37 cases amongst a crew of 400 personnel. Of 13 samples examined from cases amongst the crew, six enteric viruses were detected by reverse transcriptase polymerase chain reaction (RT-PCR). Five different viruses were identified including, three norovirus genotypes, a sapovirus and a rotavirus. No multiple infections were detected. A common food source was implicated in the outbreak and epidemiological analysis showed a statistically significant association with salad as the source of the outbreak, with a relative risk of 3.41 (95% confidence interval of 1.7-6.81) of eating salad on a particular date prior to the onset of symptoms. Faecal contamination of the salad at source was the most probable explanation for the diversity of viruses detected and characterized. PMID:15724709
NASA Astrophysics Data System (ADS)
Leski, T. A.; Ansumana, R.; Jimmy, D. H.; Bangura, U.; Malanoski, A. P.; Lin, B.; Stenger, D. A.
2011-06-01
Multiplexed microbial diagnostic assays are a promising method for detection and identification of pathogens causing syndromes characterized by nonspecific symptoms in which traditional differential diagnosis is difficult. Also such assays can play an important role in outbreak investigations and environmental screening for intentional or accidental release of biothreat agents, which requires simultaneous testing for hundreds of potential pathogens. The resequencing pathogen microarray (RPM) is an emerging technological platform, relying on a combination of massively multiplex PCR and high-density DNA microarrays for rapid detection and high-resolution identification of hundreds of infectious agents simultaneously. The RPM diagnostic system was deployed in Sierra Leone, West Africa in collaboration with Njala University and Mercy Hospital Research Laboratory located in Bo. We used the RPM-Flu microarray designed for broad-range detection of human respiratory pathogens, to investigate a suspected outbreak of avian influenza in a number of poultry farms in which significant mortality of chickens was observed. The microarray results were additionally confirmed by influenza specific real-time PCR. The results of the study excluded the possibility that the outbreak was caused by influenza, but implicated Klebsiella pneumoniae as a possible pathogen. The outcome of this feasibility study confirms that application of broad-spectrum detection platforms for outbreak investigation in low-resource locations is possible and allows for rapid discovery of the responsible agents, even in cases when different agents are suspected. This strategy enables quick and cost effective detection of low probability events such as outbreak of a rare disease or intentional release of a biothreat agent.
Ribeiro, Juliane; Lorenzetti, Elis; Alfieri, Alice Fernandes; Alfieri, Amauri Alcindo
2016-03-01
Worldwide diarrhea outbreaks in cattle herds are more frequently detected in calves being that diarrhea outbreaks in adult cattle are not common. Winter dysentery (WD) is a bovine coronavirus (BCoV) enteric infection that is more reported in Northern hemisphere. Seasonal outbreaks of WD in adult cattle occur mainly in dairy cows. WD has not been described in beef cattle herds of tropical countries. This study describes the molecular detection of BCoV in a diarrhea outbreak in beef cattle steers (Nellore) raised on pasture in Parana, southern Brazil. During the outbreak, the farm had about 600 fattening steers. Watery and bloody diarrhea unresponsive to systemic broad-spectrum antibiotic therapy reveals a morbidity rate of approximately 15 %. The BCoV N gene was identified in 42.9 % (6/14) of the diarrheic fecal samples evaluated by semi-nested polymerase chain reaction (SN-PCR) technique. Other enteric microorganisms occasionally identified in adult cattle and evaluated in this study such as bovine groups A, B, and C rotavirus, bovine viral diarrhea virus, bovine torovirus, aichivirus B, and Eimeria sp. were not identified in the fecal samples. To the best knowledge of the authors, this is the first description of the BCoV diagnosis in fecal samples collected in a diarrhea outbreak in adult beef cattle grazing in the grass in a tropical country.
Sommerstein, Rami; Führer, Urs; Lo Priore, Elia; Casanova, Carlo; Meinel, Dominik M; Seth-Smith, Helena MB; Kronenberg, Andreas; Koch, Daniel; Senn, Laurence; Widmer, Andreas F; Egli, Adrian; Marschall, Jonas
2017-01-01
We describe an outbreak of Burkholderia stabilis associated with contaminated washing gloves, a commercially available Class I medical device. Triggered by an increase in Burkholderia cepacia complex (BCC) bacteremias and the detection of BCC in unopened packages of washing gloves, an ad hoc national outbreak committee comprising representatives of a public health organisation, a regulatory agency, and an expert association convened and commissioned an outbreak investigation. The investigation included retrospective case finding across Switzerland and whole genome sequencing (WGS) of isolates from cases and gloves. The investigation revealed that BCC were detected in clinical samples of 46 cases aged 17 to 91 years (33% females) from nine institutions between May 2015 and August 2016. Twenty-two isolates from case patients and 16 from washing gloves underwent WGS. All available outbreak isolates clustered within a span of < 19 differing alleles, while 13 unrelated clinical isolates differed by > 1,500 alleles. This BCC outbreak was rapidly identified, communicated, investigated and halted by an ad hoc collaboration of multiple stakeholders. WGS served as useful tool for confirming the source of the outbreak. This outbreak also highlights current regulatory limitations regarding Class I medical devices and the usefulness of a nationally coordinated outbreak response. PMID:29233255
Timmers, Molly A.; Bird, Christopher E.; Skillings, Derek J.; Smouse, Peter E.; Toonen, Robert J.
2012-01-01
One of the most significant biological disturbances on a tropical coral reef is a population outbreak of the fecund, corallivorous crown-of-thorns sea star, Acanthaster planci. Although the factors that trigger an initial outbreak may vary, successive outbreaks within and across regions are assumed to spread via the planktonic larvae released from a primary outbreak. This secondary outbreak hypothesis is predominantly based on the high dispersal potential of A. planci and the assertion that outbreak populations (a rogue subset of the larger population) are genetically more similar to each other than they are to low-density non-outbreak populations. Here we use molecular techniques to evaluate the spatial scale at which A. planci outbreaks can propagate via larval dispersal in the central Pacific Ocean by inferring the location and severity of gene flow restrictions from the analysis of mtDNA control region sequence (656 specimens, 17 non-outbreak and six outbreak locations, six archipelagos, and three regions). Substantial regional, archipelagic, and subarchipelagic-scale genetic structuring of A. planci populations indicate that larvae rarely realize their dispersal potential and outbreaks in the central Pacific do not spread across the expanses of open ocean. On a finer scale, genetic partitioning was detected within two of three islands with multiple sampling sites. The finest spatial structure was detected at Pearl & Hermes Atoll, between the lagoon and forereef habitats (<10 km). Despite using a genetic marker capable of revealing subtle partitioning, we found no evidence that outbreaks were a rogue genetic subset of a greater population. Overall, outbreaks that occur at similar times across population partitions are genetically independent and likely due to nutrient inputs and similar climatic and ecological conditions that conspire to fuel plankton blooms. PMID:22363570
GHOST: global hepatitis outbreak and surveillance technology.
Longmire, Atkinson G; Sims, Seth; Rytsareva, Inna; Campo, David S; Skums, Pavel; Dimitrova, Zoya; Ramachandran, Sumathi; Medrzycki, Magdalena; Thai, Hong; Ganova-Raeva, Lilia; Lin, Yulin; Punkova, Lili T; Sue, Amanda; Mirabito, Massimo; Wang, Silver; Tracy, Robin; Bolet, Victor; Sukalac, Thom; Lynberg, Chris; Khudyakov, Yury
2017-12-06
Hepatitis C is a major public health problem in the United States and worldwide. Outbreaks of hepatitis C virus (HCV) infections associated with unsafe injection practices, drug diversion, and other exposures to blood are difficult to detect and investigate. Effective HCV outbreak investigation requires comprehensive surveillance and robust case investigation. We previously developed and validated a methodology for the rapid and cost-effective identification of HCV transmission clusters. Global Hepatitis Outbreak and Surveillance Technology (GHOST) is a cloud-based system enabling users, regardless of computational expertise, to analyze and visualize transmission clusters in an independent, accurate and reproducible way. We present and explore performance of several GHOST implemented algorithms using next-generation sequencing data experimentally obtained from hypervariable region 1 of genetically related and unrelated HCV strains. GHOST processes data from an entire MiSeq run in approximately 3 h. A panel of seven specimens was used for preparation of six repeats of MiSeq libraries. Testing sequence data from these libraries by GHOST showed a consistent transmission linkage detection, testifying to high reproducibility of the system. Lack of linkage among genetically unrelated HCV strains and constant detection of genetic linkage between HCV strains from known transmission pairs and from follow-up specimens at different levels of MiSeq-read sampling indicate high specificity and sensitivity of GHOST in accurate detection of HCV transmission. GHOST enables automatic extraction of timely and relevant public health information suitable for guiding effective intervention measures. It is designed as a virtual diagnostic system intended for use in molecular surveillance and outbreak investigations rather than in research. The system produces accurate and reproducible information on HCV transmission clusters for all users, irrespective of their level of bioinformatics expertise. Improvement in molecular detection capacity will contribute to increasing the rate of transmission detection, thus providing opportunity for rapid, accurate and effective response to outbreaks of hepatitis C. Although GHOST was originally developed for hepatitis C surveillance, its modular structure is readily applicable to other infectious diseases. Worldwide availability of GHOST for the detection of HCV transmissions will foster deeper involvement of public health researchers and practitioners in hepatitis C outbreak investigation.
Causes of Outbreaks Associated with Drinking Water in the United States from 1971 to 2006
Craun, Gunther F.; Brunkard, Joan M.; Yoder, Jonathan S.; Roberts, Virginia A.; Carpenter, Joe; Wade, Tim; Calderon, Rebecca L.; Roberts, Jacquelin M.; Beach, Michael J.; Roy, Sharon L.
2010-01-01
Summary: Since 1971, the CDC, EPA, and Council of State and Territorial Epidemiologists (CSTE) have maintained the collaborative national Waterborne Disease and Outbreak Surveillance System (WBDOSS) to document waterborne disease outbreaks (WBDOs) reported by local, state, and territorial health departments. WBDOs were recently reclassified to better characterize water system deficiencies and risk factors; data were analyzed for trends in outbreak occurrence, etiologies, and deficiencies during 1971 to 2006. A total of 833 WBDOs, 577,991 cases of illness, and 106 deaths were reported during 1971 to 2006. Trends of public health significance include (i) a decrease in the number of reported outbreaks over time and in the annual proportion of outbreaks reported in public water systems, (ii) an increase in the annual proportion of outbreaks reported in individual water systems and in the proportion of outbreaks associated with premise plumbing deficiencies in public water systems, (iii) no change in the annual proportion of outbreaks associated with distribution system deficiencies or the use of untreated and improperly treated groundwater in public water systems, and (iv) the increasing importance of Legionella since its inclusion in WBDOSS in 2001. Data from WBDOSS have helped inform public health and regulatory responses. Additional resources for waterborne disease surveillance and outbreak detection are essential to improve our ability to monitor, detect, and prevent waterborne disease in the United States. PMID:20610821
Mathur, P K; Herrero-Medrano, J M; Alexandri, P; Knol, E F; ten Napel, J; Rashidi, H; Mulder, H A
2014-12-01
A method was developed and tested to estimate challenge load due to disease outbreaks and other challenges in sows using reproduction records. The method was based on reproduction records from a farm with known disease outbreaks. It was assumed that the reduction in weekly reproductive output within a farm is proportional to the magnitude of the challenge. As the challenge increases beyond certain threshold, it is manifested as an outbreak. The reproduction records were divided into 3 datasets. The first dataset called the Training dataset consisted of 57,135 reproduction records from 10,901 sows from 1 farm in Canada with several outbreaks of porcine reproductive and respiratory syndrome (PRRS). The known disease status of sows was regressed on the traits number born alive, number of losses as a combination of still birth and mummified piglets, and number of weaned piglets. The regression coefficients from this analysis were then used as weighting factors for derivation of an index measure called challenge load indicator. These weighting factors were derived with i) a two-step approach using residuals or year-week solutions estimated from a previous step, and ii) a single-step approach using the trait values directly. Two types of models were used for each approach: a logistic regression model and a general additive model. The estimates of challenge load indicator were then compared based on their ability to detect PRRS outbreaks in a Test dataset consisting of records from 65,826 sows from 15 farms in the Netherlands. These farms differed from the Canadian farm with respect to PRRS virus strains, severity and frequency of outbreaks. The single-step approach using a general additive model was best and detected 14 out of the 15 outbreaks. This approach was then further validated using the third dataset consisting of reproduction records of 831,855 sows in 431 farms located in different countries in Europe and America. A total of 41 out of 48 outbreaks detected using data analysis were confirmed based on diagnostic information received from the farms. Among these, 30 outbreaks were due to PRRS while 11 were due to other diseases and challenging conditions. The results suggest that proposed method could be useful for estimation of challenge load and detection of challenge phases such as disease outbreaks.
[Meningitis outbreak caused by Echovirus serotype 30 in the Valencian Community].
Juliá, M Lirios; Colomina, Javier; Domínguez, Victoria; Orta, Nieves; Guerrero, Antonio
2009-05-01
Aseptic meningitis can be caused by several agents, and in many cases the etiology remains unknown. The aim of this study to analyze the clinical and epidemiological characteristics of a meningitis outbreak detected in Health Department 11 of the Valencian Community (Spain). The study was performed in children hospitalized between November and December 2006 with meningitis symptoms, CSF pleocytosis, and negative CSF bacteriological culture. An epidemiological survey was conducted among cases and family members. Virus detection and phylogenetic analysis were performed with molecular biology techniques. The outbreak affected at least 44 children, with a mean age (standard deviation) of 5.5 years (2.9). The average hospital stay was 3.1 days and outcome was favorable in all cases. In 24 patients the CSF specimen sufficed for viral detection by PCR; enteroviruses ultimately serotyped as echovirus 30 were detected in 12 of them (50%). This serotype has been recently found in other parts of our country. Detection of echovirus 30 in CSF and the epidemiological presentation of cases enabled determination of the etiology of the outbreak. This finding coincided in time with other outbreaks of echovirus 30 in Spain, a fact that may explain the epidemic situation in the Valencian Community during 2006. Establishment of a national surveillance network for monitoring systemic enterovirus infection would provide data on the circulation patterns and identify new emerging serotypes.
Vaz, Rui G.; Mkanda, Pascal; Banda, Richard; Komkech, William; Ekundare-Famiyesin, Olubowale O.; Onyibe, Rosemary; Abidoye, Sunday; Nsubuga, Peter; Maleghemi, Sylvester; Hannah-Murele, Bolatito; Tegegne, Sisay G.
2016-01-01
Background. The current West African outbreak of the Ebola virus disease (EVD) began in Guinea in December 2013 and rapidly spread to Liberia and Sierra Leone. On 20 July 2014, a sick individual flew into Lagos, Nigeria, from Monrovia, Liberia, setting off an outbreak in Lagos and later in Port Harcourt city. The government of Nigeria, supported by the World Health Organization and other partners, mounted a response to the outbreak relying on the polio program experiences and infrastructure. On 20 October 2014, the country was declared free of EVD. Methods. We examined the organization and operations of the response to the 2014 EVD outbreak in Nigeria and how experiences and support from the country's polio program infrastructure accelerated the outbreak response. Results. The deputy incident manager of the National Polio Emergency Operations Centre was appointed the incident manager of the Ebola Emergency Operations Centre (EEOC), the body that coordinated and directed the response to the EVD outbreak in the country. A total of 892 contacts were followed up, and blood specimens were collected from 61 persons with suspected EVD and tested in designated laboratories. Of these, 19 (31%) were positive for Ebola, and 11 (58%) of the case patients were healthcare workers. The overall case-fatality rate was 40%. EVD sensitization and training were conducted during the outbreak and for 2 months after the outbreak ended. The World Health Organization deployed its surveillance and logistics personnel from non–Ebola-infected states to support response activities in Lagos and Rivers states. Conclusions. The support from the polio program infrastructure, particularly the coordination mechanism adopted (the EEOC), the availability of skilled personnel in the polio program, and lessons learned from managing the polio eradication program greatly contributed to the speedy containment of the 2014 EVD outbreak in Nigeria. PMID:26908718
Bhatnagar, Vibha; Stoto, Michael A; Morton, Sally C; Boer, Rob; Bozzette, Samuel A
2006-05-05
Because smallpox (variola major) may be used as a biological weapon, we reviewed outbreaks in post-World War II Europe and North America in order to understand smallpox transmission patterns. A systematic review was used to identify papers from the National Library of Medicine, Embase, Biosis, Cochrane Library, Defense Technical Information Center, WorldCat, and reference lists of included publications. Two authors reviewed selected papers for smallpox outbreaks. 51 relevant outbreaks were identified from 1,389 publications. The median for the effective first generation reproduction rate (initial R) was 2 (range 0-38). The majority outbreaks were small (less than 5 cases) and contained within one generation. Outbreaks with few hospitalized patients had low initial R values (median of 1) and were prolonged if not initially recognized (median of 3 generations); outbreaks with mostly hospitalized patients had higher initial R values (median 12) and were shorter (median of 3 generations). Index cases with an atypical presentation of smallpox were less likely to have been diagnosed with smallpox; outbreaks in which the index case was not correctly diagnosed were larger (median of 27.5 cases) and longer (median of 3 generations) compared to outbreaks in which the index case was correctly diagnosed (median of 3 cases and 1 generation). Patterns of spread during Smallpox outbreaks varied with circumstances, but early detection and implementation of control measures is a most important influence on the magnitude of outbreaks. The majority of outbreaks studied in Europe and North America were controlled within a few generations if detected early.
Proctor, M. E.; Blair, K. A.; Davis, J. P.
1998-01-01
Following the 1993 Milwaukee cryptosporidiosis outbreak, we examined data from eight sources available during the time of the outbreak. Although there was a remarkable temporal correspondence of surveillance peaks, the most timely data involved use of systems in which personnel with existing close ties to public health programmes perceived the importance of providing information despite workload constraints associated with an outbreak. During the investigation, surveillance systems which could be easily linked with laboratory data, were flexible in adding new variables, and which demonstrated low baseline variability were most useful. Geographically fixed nursing home residents served as an ideal population with nonconfounded exposures. Use of surrogate measurements of morbidity can trigger worthwhile public health responses in advance of laboratory-confirmed diagnosis and help reduce total morbidity associated with an outbreak. This report describes the relative strengths and weaknesses of these surveillance methods for community-wide waterborne illness detection and their application in outbreak decision making. PMID:9528817
Fan, Yunzhou; Wang, Ying; Jiang, Hongbo; Yang, Wenwen; Yu, Miao; Yan, Weirong; Diwan, Vinod K; Xu, Biao; Dong, Hengjin; Palm, Lars; Nie, Shaofa
2014-01-01
Syndromic surveillance promotes the early detection of diseases outbreaks. Although syndromic surveillance has increased in developing countries, performance on outbreak detection, particularly in cases of multi-stream surveillance, has scarcely been evaluated in rural areas. This study introduces a temporal simulation model based on healthcare-seeking behaviors to evaluate the performance of multi-stream syndromic surveillance for influenza-like illness. Data were obtained in six towns of rural Hubei Province, China, from April 2012 to June 2013. A Susceptible-Exposed-Infectious-Recovered model generated 27 scenarios of simulated influenza A (H1N1) outbreaks, which were converted into corresponding simulated syndromic datasets through the healthcare-behaviors model. We then superimposed converted syndromic datasets onto the baselines obtained to create the testing datasets. Outbreak performance of single-stream surveillance of clinic visit, frequency of over the counter drug purchases, school absenteeism, and multi-stream surveillance of their combinations were evaluated using receiver operating characteristic curves and activity monitoring operation curves. In the six towns examined, clinic visit surveillance and school absenteeism surveillance exhibited superior performances of outbreak detection than over the counter drug purchase frequency surveillance; the performance of multi-stream surveillance was preferable to signal-stream surveillance, particularly at low specificity (Sp <90%). The temporal simulation model based on healthcare-seeking behaviors offers an accessible method for evaluating the performance of multi-stream surveillance.
USDA-ARS?s Scientific Manuscript database
Salmonella spp. are one of the leading causes of foodborne outbreaks in the United States and globally. Current detection and characterization techniques for Salmonella are time consuming and rapid methods could greatly benefit outbreak investigation, new case prevention and disease treatment. In th...
Plasmodium falciparum Malaria, Southern Algeria, 2007
Gassen, Ibrahim; Khechache, Yacine; Lamali, Karima; Tchicha, Boualem; Brengues, Cécile; Menegon, Michela; Severini, Carlo; Fontenille, Didier; Harrat, Zoubir
2010-01-01
An outbreak of Plasmodium falciparum malaria occurred in Tinzaouatine in southern Algeria in 2007. The likely vector, Anopheles gambiae mosquitoes, had not been detected in Algeria. Genes for resistance to chloroquine were detected in the parasite. The outbreak shows the potential for an increase in malaria vectors in Algeria. PMID:20113565
USDA-ARS?s Scientific Manuscript database
Salmonella spp. are one of the leading causes of foodborne outbreaks in the United States and globally. Current detection and characterization techniques for Salmonellae are time consuming and costly, and rapid methods could greatly benefit outbreak investigation, new case prevention and disease tre...
Boisen, Matthew L.; Schieffelin, John S.; Goba, Augustine; Oottamasathien, Darin; Jones, Abigail B.; Shaffer, Jeffrey G.; Hastie, Kathryn M.; Hartnett, Jessica N.; Momoh, Mambu; Fullah, Mohammed; Gabiki, Michael; Safa, Sidiki; Zandonatti, Michelle; Fusco, Marnie; Bornholdt, Zach; Abelson, Dafna; Gire, Stephen K.; Andersen, Kristian G.; Tariyal, Ridhi; Stremlau, Mathew; Cross, Robert W.; Geisbert, Joan B.; Pitts, Kelly R.; Geisbert, Thomas W.; Kulakoski, Peter; Wilson, Russell B.; Henderson, Lee; Sabeti, Pardis C.; Grant, Donald S.; Garry, Robert F.; Saphire, Erica O.; Khan, Sheik Humarr
2015-01-01
Abstract Lassa fever (LF) is a severe viral hemorrhagic fever caused by Lassa virus (LASV). The LF program at the Kenema Government Hospital (KGH) in Eastern Sierra Leone currently provides diagnostic services and clinical care for more than 500 suspected LF cases per year. Nearly two-thirds of suspected LF patients presenting to the LF Ward test negative for either LASV antigen or anti-LASV immunoglobulin M (IgM), and therefore are considered to have a non-Lassa febrile illness (NLFI). The NLFI patients in this study were generally severely ill, which accounts for their high case fatality rate of 36%. The current studies were aimed at determining possible causes of severe febrile illnesses in non-LF cases presenting to the KGH, including possible involvement of filoviruses. A seroprevalence survey employing commercial enzyme-linked immunosorbent assay tests revealed significant IgM and IgG reactivity against dengue virus, chikungunya virus, West Nile virus (WNV), Leptospira, and typhus. A polymerase chain reaction–based survey using sera from subjects with acute LF, evidence of prior LASV exposure, or NLFI revealed widespread infection with Plasmodium falciparum malaria in febrile patients. WNV RNA was detected in a subset of patients, and a 419 nt amplicon specific to filoviral L segment RNA was detected at low levels in a single patient. However, 22% of the patients presenting at the KGH between 2011 and 2014 who were included in this survey registered anti-Ebola virus (EBOV) IgG or IgM, suggesting prior exposure to this agent. The 2014 Ebola virus disease (EVD) outbreak is already the deadliest and most widely dispersed outbreak of its kind on record. Serological evidence reported here for possible human exposure to filoviruses in Sierra Leone prior to the current EVD outbreak supports genetic analysis that EBOV may have been present in West Africa for some time prior to the 2014 outbreak. PMID:25531344
Cheese-related listeriosis outbreak, Portugal, March 2009 to February 2012.
Magalhaes, R; Almeida, G; Ferreira, V; Santos, I; Silva, J; Mendes, M M; Pita, J; Mariano, G; Mancio, I; Sousa, M M; Farber, J; Pagotto, F; Teixeira, P
2015-04-30
In Portugal, listeriosis has been notifiable since April 2014, but there is no active surveillance programme for the disease. A retrospective study involving 25 national hospitals led to the detection of an outbreak that occurred between March 2009 and February 2012. The amount of time between the start of the outbreak and its detection was 16 months. Of the 30 cases of listeriosis reported, 27 were in the Lisbon and Vale do Tejo region. Two cases were maternal/neonatal infections and one resulted in fetal loss. The mean age of the non-maternal/neonatal cases was 59 years (standard deviation: 17); 13 cases were more than 65 years old. The case fatality rate was 36.7%. All cases were caused by molecular serogroup IVb isolates indistinguishable by pulsed-field gel electrophoresis and ribotype profiles. Collaborative investigations with the national health and food safety authorities identified cheese as the probable source of infection, traced to a processing plant. The magnitude of this outbreak, the first reported food-borne listeriosis outbreak in Portugal, highlights the importance of having an effective listeriosis surveillance system in place for early detection and resolution of outbreaks, as well as the need for a process for the prompt submission of Listeria monocytogenes isolates for routine laboratory typing.
Lorca-Oró, Cristina; López-Olvera, Jorge Ramón; Ruiz-Fons, Francisco; Acevedo, Pelayo; García-Bocanegra, Ignacio; Oleaga, Álvaro; Gortázar, Christian; Pujols, Joan
2014-01-01
Wild and domestic ruminants are susceptible to Bluetongue virus (BTV) infection. Three BTV serotypes (BTV-4, BTV-1 and BTV-8) have been detected in Spain in the last decade. Even though control strategies have been applied to livestock, BTV circulation has been frequently detected in wild ruminant populations in Spain. The aim of the present study is to assess the role for wild ruminants in maintaining BTV after the vaccination programs in livestock in mainland Spain. A total of 931 out 1,914 (48.6%) serum samples, collected from eight different wild ruminant species between 2006 and 2011, were BTV positive by ELISA. In order to detect specific antibodies against BTV-1, BTV-4 and BTV-8, positive sera were also tested by serumneutralisation test (SNT). From the ELISA positive samples that could be tested by SNT (687 out of 931), 292 (42.5%) showed neutralising antibodies against one or two BTV serotypes. For each BTV seroptype, the number of outbreaks in livestock (11,857 outbreaks in total) was modelled with pure autoregressive models and the resulting smoothed values, representing the predicted number of BTV outbreaks in livestock at municipality level, were positively correlated with BTV persistence in wild species. The strength of this relationship significantly decreased as red deer (Cervus elaphus) population abundance increased. In addition, BTV RNA was detected by real time RT-PCR in 32 out of 311 (10.3%) spleen samples from seropositive animals. Although BT outbreaks in livestock have decreased substantially after vaccination campaigns, our results indicated that wild ruminants have been exposed to BTV in territories where outbreaks in domestic animals occurred. The detection of BTV RNA and spatial association between BT outbreaks in livestock and BTV rates in red deer are consistent with the hypothesis of virus circulation and BTV maintenance within Iberian wild ruminant populations. PMID:24940879
A Space–Time Permutation Scan Statistic for Disease Outbreak Detection
Kulldorff, Martin; Heffernan, Richard; Hartman, Jessica; Assunção, Renato; Mostashari, Farzad
2005-01-01
Background The ability to detect disease outbreaks early is important in order to minimize morbidity and mortality through timely implementation of disease prevention and control measures. Many national, state, and local health departments are launching disease surveillance systems with daily analyses of hospital emergency department visits, ambulance dispatch calls, or pharmacy sales for which population-at-risk information is unavailable or irrelevant. Methods and Findings We propose a prospective space–time permutation scan statistic for the early detection of disease outbreaks that uses only case numbers, with no need for population-at-risk data. It makes minimal assumptions about the time, geographical location, or size of the outbreak, and it adjusts for natural purely spatial and purely temporal variation. The new method was evaluated using daily analyses of hospital emergency department visits in New York City. Four of the five strongest signals were likely local precursors to citywide outbreaks due to rotavirus, norovirus, and influenza. The number of false signals was at most modest. Conclusion If such results hold up over longer study times and in other locations, the space–time permutation scan statistic will be an important tool for local and national health departments that are setting up early disease detection surveillance systems. PMID:15719066
Woods, Jacquelina W; Calci, Kevin R; Marchant-Tambone, Joey G; Burkhardt, William
2016-10-01
Human noroviruses are the leading cause of non-bacterial shellfish associated gastroenteritis. Here we report on the detection and characterization of norovirus (NoV) in shellfish associated outbreaks. Requests were received from state and federal officials for technical assistance in the analysis of shellfish for NoV and male specific coliphage (MSC; an enteric virus surrogate) during the years 2009 thru 2014. In outbreaks where NoV was detected, genogroup II (GII) levels ranged from 2.4 to 82.0 RT-qPCR U/g of digestive diverticula (DD) while NoV genogroup I (GI) levels ranged from 1.5 to 29.8 RT-qPCR U/g of DD. Murine norovirus extraction efficiencies ranged between 50 and 85%. MSC levels ranged from <6 to 80 PFU/100 g. Phylogenetic analysis of the outbreak sequences revealed strains clustering with GI.8, GI.4, GII.3, GII.4, GII.7, and GII.21. There was 100% homology between the shellfish and clinical strains occurring in 2 of 8 outbreaks. Known shellfish consumption data demonstrated probable infectious particles ingested as low as 12. These investigations demonstrate effective detection, quantification, and characterization of NoV in shellfish associated with illness. Published by Elsevier Ltd.
Diagnostic Evasion of Highly-Resistant Microorganisms: A Critical Factor in Nosocomial Outbreaks.
Zhou, Xuewei; Friedrich, Alexander W; Bathoorn, Erik
2017-01-01
Highly resistant microorganisms (HRMOs) may evade screening strategies used in routine diagnostics. Bacteria that have evolved to evade diagnostic tests may have a selective advantage in the nosocomial environment. Evasion of resistance detection can result from the following mechanisms: low-level expression of resistance genes not resulting in detectable resistance, slow growing variants, mimicry of wild-type-resistance, and resistance mechanisms that are only detected if induced by antibiotic pressure. We reviewed reports on hospital outbreaks in the Netherlands over the past 5 years. Remarkably, many outbreaks including major nation-wide outbreaks were caused by microorganisms able to evade resistance detection by diagnostic screening tests. We describe various examples of diagnostic evasion by several HRMOs and discuss this in a broad and international perspective. The epidemiology of hospital-associated bacteria may strongly be affected by diagnostic screening strategies. This may result in an increasing reservoir of resistance genes in hospital populations that is unnoticed. The resistance elements may horizontally transfer to hosts with systems for high-level expression, resulting in a clinically significant resistance problem. We advise to communicate the identification of HRMOs that evade diagnostics within national and regional networks. Such signaling networks may prevent inter-hospital outbreaks, and allow collaborative development of adapted diagnostic tests.
Michael, Charles A; Waziri, Ndadilnasiya; Gunnala, Rajni; Biya, Oladayo; Kretsinger, Katrina; Wiesen, Eric; Goodson, James L; Esapa, Lisa; Gidado, Saheed; Uba, Belinda; Nguku, Patrick; Cochi, Stephen
2017-07-01
From 2012 to date, Nigeria has been the focus of intensified polio eradication efforts. Large investments made by multiple partner organizations and the federal Ministry of Health to support strategies and resources, including personnel, for increasing vaccination coverage and improved performance monitoring paid off, as the number of wild poliovirus (WPV) cases detected in Nigeria were reduced significantly, from 122 in 2012 to 6 in 2014. No WPV cases were detected in Nigeria in 2015 and as at March 2017, only 4 WPV cases had been detected. Given the momentum gained toward polio eradication, these resources seem well positioned to help advance other priority health agendas in Nigeria, particularly the control of vaccine-preventable diseases, such as measles. Despite implementation of mass measles vaccination campaigns, measles outbreaks continue to occur regularly in Nigeria, leading to high morbidity and mortality rates for children <5 years of age. The National Stop Transmission of Polio (NSTOP) program was collaboratively established in 2012 to create a network of staff working at national, state, and district levels in areas deemed high risk for vaccine-preventable disease outbreaks. As an example of how the polio legacy can create long-lasting improvements to public health beyond polio, the Centers for Disease Control and Prevention will transition >180 NSTOP officers to provide technical experience to improve measles surveillance, routine vaccination coverage, and outbreak investigation and response in high-risk areas. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America.
Time delays in the response to the Neisseria meningitidis serogroup C outbreak in Nigeria - 2017.
Hassan, Assad; Mustapha, G U; Lawal, Bola B; Na'uzo, Aliyu M; Ismail, Raji; Womi-Eteng Oboma, Eteng; Oyebanji, Oyeronke; Agenyi, Jeremiah; Thomas, Chima; Balogun, Muhammad Shakir; Dalhat, Mahmood M; Nguku, Patrick; Ihekweazu, Chikwe
2018-01-01
Nigeria reports high rates of mortality linked with recurring meningococcal meningitis outbreaks within the African meningitis belt. Few studies have thoroughly described the response to these outbreaks to provide strong and actionable public health messages. We describe how time delays affected the response to the 2016/2017 meningococcal meningitis outbreak in Nigeria. Using data from Nigeria Centre for Disease Control (NCDC), National Primary Health Care Development Agency (NPHCDA), World Health Organisation (WHO), and situation reports of rapid response teams, we calculated attack and death rates of reported suspected meningococcal meningitis cases per week in Zamfara, Sokoto and Yobe states respectively, between epidemiological week 49 in 2016 and epidemiological week 25 in 2017. We identified when alert and epidemic thresholds were crossed and determined when the outbreak was detected and notified in each state. We examined response activities to the outbreak. There were 12,535 suspected meningococcal meningitis cases and 877 deaths (CFR: 7.0%) in the three states. It took an average time of three weeks before the outbreaks were detected and notified to NCDC. Four weeks after receiving notification, an integrated response coordinating centre was set up by NCDC and requests for vaccines were sent to International Coordinating Group (ICG) on vaccine provision. While it took ICG one week to approve the requests, it took an average of two weeks for approximately 41% of requested vaccines to arrive. On the average, it took nine weeks from the date the epidemic threshold was crossed to commencement of reactive vaccination in the three states. There were delays in detection and notification of the outbreak, in coordinating response activities, in requesting for vaccines and their arrival from ICG, and in initiating reactive vaccination. Reducing these delays in future outbreaks could help decrease the morbidity and mortality linked with meningococcal meningitis outbreaks.
Bertherat, Eric; Mueller, Melissa J.; Shako, Jean-Christophe; Picardeau, Mathieu
2014-01-01
Conditions in the Democratic Republic of the Congo provide an ideal environment for leptospirosis and plague, both of which can cause severe pulmonary manifestations. In December 2004, an outbreak of lethal pneumonia occurred in a local mining camp, affecting 130 persons and killing 57 of them. Clinical signs, fast disease spread, and initial laboratory investigations suggested pneumonic plague. While leptospirosis had not recently been described in the region, it was considered as a differential diagnosis. Anti-Leptospira antibodies were detected by microscopic agglutination test (MAT). A confirmed case of leptospirosis was defined as having consistent clinical signs and any one of the following: seroconversion or four-fold increase in MAT titre for paired serum samples, or a MAT titre ≥ 1:400 for acute-phase serum samples. Twenty-nine of the 54 patients or convalescents tested for leptospirosis were seropositive. Two cases showed a confirmed infection for both plague and leptospirosis. While evidence supports the plague nature of this outbreak, the results suggest that some of the suspected plague cases might be due to leptospirosis. In any case, this diagnosis will have to be evoked in the future if a similar outbreak occurs in this region of Africa. PMID:24514425
Bertherat, Eric; Mueller, Melissa J; Shako, Jean-Christophe; Picardeau, Mathieu
2014-02-07
Conditions in the Democratic Republic of the Congo provide an ideal environment for leptospirosis and plague, both of which can cause severe pulmonary manifestations. In December 2004, an outbreak of lethal pneumonia occurred in a local mining camp, affecting 130 persons and killing 57 of them. Clinical signs, fast disease spread, and initial laboratory investigations suggested pneumonic plague. While leptospirosis had not recently been described in the region, it was considered as a differential diagnosis. Anti-Leptospira antibodies were detected by microscopic agglutination test (MAT). A confirmed case of leptospirosis was defined as having consistent clinical signs and any one of the following: seroconversion or four-fold increase in MAT titre for paired serum samples, or a MAT titre ≥ 1:400 for acute-phase serum samples. Twenty-nine of the 54 patients or convalescents tested for leptospirosis were seropositive. Two cases showed a confirmed infection for both plague and leptospirosis. While evidence supports the plague nature of this outbreak, the results suggest that some of the suspected plague cases might be due to leptospirosis. In any case, this diagnosis will have to be evoked in the future if a similar outbreak occurs in this region of Africa.
Nosocomial transmission of respiratory syncytial virus in an outpatient cancer center.
Chu, Helen Y; Englund, Janet A; Podczervinski, Sara; Kuypers, Jane; Campbell, Angela P; Boeckh, Michael; Pergam, Steven A; Casper, Corey
2014-06-01
Respiratory syncytial virus (RSV) outbreaks in inpatient settings are associated with poor outcomes in cancer patients. The use of molecular epidemiology to document RSV transmission in the outpatient setting has not been well described. We performed a retrospective cohort study of 2 nosocomial outbreaks of RSV at the Seattle Cancer Care Alliance. Subjects included patients seen at the Seattle Cancer Care Alliance with RSV detected in 2 outbreaks in 2007-2008 and 2012 and all employees with respiratory viruses detected in the 2007-2008 outbreak. A subset of samples was sequenced using semi-nested PCR targeting the RSV attachment glycoprotein coding region. Fifty-one cases of RSV were identified in 2007-2008. Clustering of identical viral strains was detected in 10 of 15 patients (67%) with RSV sequenced from 2007 to 2008. As part of a multimodal infection control strategy implemented as a response to the outbreak, symptomatic employees had nasal washes collected. Of 254 employee samples, 91 (34%) tested positive for a respiratory virus, including 14 with RSV. In another RSV outbreak in 2012, 24 cases of RSV were identified; 9 of 10 patients (90%) had the same viral strain, and 1 (10%) had another viral strain. We document spread of clonal strains within an outpatient cancer care setting. Infection control interventions should be implemented in outpatient, as well as inpatient, settings to reduce person-to-person transmission and limit progression of RSV outbreaks. Copyright © 2014 American Society for Blood and Marrow Transplantation. All rights reserved.
Nosocomial Transmission of Respiratory Syncytial Virus in an Outpatient Cancer Center
Chu, Helen Y.; Englund, Janet A.; Podczervinski, Sara; Kuypers, Jane; Campbell, Angela P.; Boeckh, Michael; Pergam, Steven A.; Casper, Crey
2014-01-01
Background Respiratory syncytial virus (RSV) outbreaks in inpatient settings are associated with poor outcomes in cancer patients. The use of molecular epidemiology to document RSV transmission in the outpatient setting has not been well described. Methods We performed a retrospective cohort study of two nosocomial outbreaks of RSV at the Seattle Cancer Care Alliance (SCCA). Subjects included patients seen at the SCCA with RSV detected in two outbreaks in 2007-2008 and 2012, and all employees with respiratory viruses detected in the 2007-2008 outbreak. A subset of samples was sequenced using semi-nested polymerase chain reaction targeting the RSV attachment glycoprotein coding region. Results Fifty-one cases of RSV were identified in 2007-2008. Clustering of identical viral strains was detected in 10 (67%) of 15 patients with RSV sequenced from 2007-2008. As part of a multimodal infection control strategy implemented as a response to the outbreak, symptomatic employees had nasal washes collected. Of 254 employee samples, 91 (34%) tested positive for a respiratory virus, including 14 with RSV. In another RSV outbreak in 2012, 24 cases of RSV were identified; nine (90%) of 10 patients had the same viral strain, and 1 (10%) had another viral strain. Conclusions We document spread of clonal strains within an outpatient cancer care setting. Infection control interventions should be implemented in outpatient, as well as inpatient, settings to reduce person-to-person transmission and limit progression of RSV outbreaks. PMID:24607551
Phylogeny of Yellow Fever Virus, Uganda, 2016.
Hughes, Holly R; Kayiwa, John; Mossel, Eric C; Lutwama, Julius; Staples, J Erin; Lambert, Amy J
2018-08-17
In April 2016, a yellow fever outbreak was detected in Uganda. Removal of contaminating ribosomal RNA in a clinical sample improved the sensitivity of next-generation sequencing. Molecular analyses determined the Uganda yellow fever outbreak was distinct from the concurrent yellow fever outbreak in Angola, improving our understanding of yellow fever epidemiology.
de Vries, Daniel H; Rwemisisi, Jude T; Musinguzi, Laban K; Benoni, Turinawe E; Muhangi, Denis; de Groot, Marije; Kaawa-Mafigiri, David; Pool, Robert
2016-02-16
A major challenge to outbreak control lies in early detection of viral haemorrhagic fevers (VHFs) in local community contexts during the critical initial stages of an epidemic, when risk of spreading is its highest ("the first mile"). In this paper we document how a major Ebola outbreak control effort in central Uganda in 2012 was experienced from the perspective of the community. We ask to what extent the community became a resource for early detection, and identify problems encountered with community health worker and social mobilization strategies. Analysis is based on first-hand ethnographic data from the center of a small Ebola outbreak in Luwero Country, Uganda, in 2012. Three of this paper's authors were engaged in an 18 month period of fieldwork on community health resources when the outbreak occurred. In total, 13 respondents from the outbreak site were interviewed, along with 21 key informants and 61 focus group respondents from nearby Kaguugo Parish. All informants were chosen through non-probability sampling sampling. Our data illustrate the lack of credibility, from an emic perspective, of biomedical explanations which ignore local understandings. These explanations were undermined by an insensitivity to local culture, a mismatch between information circulated and the local interpretative framework, and the inability of the emergency response team to take the time needed to listen and empathize with community needs. Stigmatization of the local community--in particular its belief in amayembe spirits--fuelled historical distrust of the external health system and engendered community-level resistance to early detection. Given the available anthropological knowledge of a previous outbreak in Northern Uganda, it is surprising that so little serious effort was made this time round to take local sensibilities and culture into account. The "first mile" problem is not only a question of using local resources for early detection, but also of making use of the contextual cultural knowledge that has already been collected and is readily available. Despite remarkable technological innovations, outbreak control remains contingent upon human interaction and openness to cultural difference.
Mora, Azucena; Herrrera, Alexandra; López, Cecilia; Dahbi, Ghizlane; Mamani, Rosalia; Pita, Julia M; Alonso, María P; Llovo, José; Bernárdez, María I; Blanco, Jesús E; Blanco, Miguel; Blanco, Jorge
2011-09-01
A Shiga-toxin-producing Escherichia coli (STEC) strain belonging to serotype O104:H4, phylogenetic group B1 and sequence type ST678, with virulence features common to the enteroaggregative E. coli (EAEC) pathotype, was reported as the cause of the recent 2011 outbreak in Germany. The outbreak strain was determined to carry several virulence factors of extraintestinal pathogenic E. coli (ExPEC) and to be resistant to a wide range of antibiotics. There are only a few reports of serotype O104:H4, which is very rare in humans and has never been detected in animals or food. Several research groups obtained the complete genome sequence of isolates of the German outbreak strain as well as the genome sequences of EAEC of serotype O104:H4 strains from Africa. Those findings suggested that horizontal genetic transfer allowed the emergence of the highly virulent Shiga-toxin-producing enteroaggregative E. coli (STEAEC) O104:H4 strain responsible for the outbreak in Germany. Epidemiologic investigations supported a linkage between the outbreaks in Germany and France and traced their origin to fenugreek seeds imported from Africa. However, there has been no isolation of the causative strain O104:H4 from any of the samples of fenugreek seeds analyzed. Following the German outbreak, we conducted a large sampling to analyze the presence of STEC, EAEC, and other types of diarrheagenic E. coli strains in Spanish vegetables. During June and July 2011, 200 vegetable samples from different origins were analyzed. All were negative for the virulent serotype O104:H4 and only one lettuce sample (0.6%) was positive for a STEC strain of serotype O146:H21 (stx1, stx2), considered of low virulence. Despite the single positive case, the hygienic and sanitary quality of Spanish vegetables proved to be quite good. In 195 of the 200 samples (98%), <10 colony-forming units (cfu) of E. coli per gram were detected, and the microbiological levels of all samples were satisfactory (<100 cfu/g). The samples were also negative for other pathotypes of diarrheagenic E. coli (EAEC, ETEC, tEPEC, and EIEC). Consistent with data from other countries, STEC belonging to serotype O157:H7 and other serotypes have been isolated from beef, milk, cheese, and domestic (cattle, sheep, goats) and wild (deer, boar, fox) animals in Spain. Nevertheless, STEC outbreaks in Spain are rare.
Ahlen, Catrine; Aas, Marianne; Krusnell, Jadwiga; Iversen, Ole-Jan
2016-01-01
Recurrent legionella outbreaks at one and the same location are common. We have identified a single Legionella pneumophila genotype associated with recurrent Legionella outbreaks over 6 years. Field emergency surveys following Legionella outbreaks were performed on a vessel in 2008, 2009 and 2013. Water samples from both the distribution and technical parts of the potable water system were analyzed with respect to L. pneumophila [Real-Time PCR, cultivation, serotyping and genotyping (PFGE)] and free-living amoebae, (FLA). Legionella pneumophila serogroup 1 was present in the ship's potable water system during every outbreak. Genotyping of the 2008 survey material showed two separate PFGE genotypes while those in 2009 and 2013 demonstrated the presence of only one of the two genotypes. FLA with intracellular L. pneumophila of the same genotype were also detected. Analyses of the freshwater system on a ship following three separate Legionella outbreaks, for L. pneumophila and FLAs, revealed a single L. pneumophila genotype and FLA (Hartmanella). It is reasonable to assume that the L. pneumophila genotype detected in the freshwater system was the causal agent in the outbreaks onboard. Persistence of an apparently low-pathogenic L. pneumophila genotype and FLA in a potable water system represent a potential risk for recurrent outbreaks.
Two consecutive nationwide outbreaks of Listeriosis in France, October 1999-February 2000.
de Valk, H; Vaillant, V; Jacquet, C; Rocourt, J; Le Querrec, F; Stainer, F; Quelquejeu, N; Pierre, O; Pierre, V; Desenclos, J C; Goulet, V
2001-11-15
In France, listeriosis surveillance is based on mandatory notification of all culture-confirmed cases, with systematic typing of isolates and routine collection of the patient's food history. From October 1999 to March 2000, two outbreaks of listeriosis were detected through this enhanced surveillance system. In outbreak 1, analysis of the food histories of cases suggested brand X "rillettes," a pâté-like meat product, as the vehicle of infection, and the outbreak strain of Listeria monocytogenes was subsequently isolated from the incriminated rillettes. In outbreak 2, a case-control study showed that consumption of jellied pork tongue was strongly associated with infection with the outbreak strain (odds ratio = 75.5, 95% confidence interval: 4.7, 1,216.0). However, trace-back results did not permit incrimination of any particular manufacturer of jellied pork tongue, and the outbreak strain was not isolated from the incriminated food or from any production sites. Consumption of jellied pork tongue was discouraged on epidemiologic evidence alone. The consecutive occurrence of these two outbreaks confirms the epidemic potential of listeriosis, even in a context of decreasing incidence, and underlines the importance of timely case-reporting and systematic typing of human L. monocytogenes strains to allow early detection and separate investigation of different clusters.
Fan, Yunzhou; Yang, Mei; Jiang, Hongbo; Wang, Ying; Yang, Wenwen; Zhang, Zhixia; Yan, Weirong; Diwan, Vinod K; Xu, Biao; Dong, Hengjin; Palm, Lars; Liu, Li; Nie, Shaofa
2014-01-01
School absenteeism is a common data source in syndromic surveillance, which allows for the detection of outbreaks at an early stage. Previous studies focused on its correlation with other data sources. In this study, we evaluated the effectiveness of control measures based on early warning signals from school absenteeism surveillance in rural Chinese schools. A school absenteeism surveillance system was established in all 17 primary schools in 3 adjacent towns in the Chinese region of Hubei. Three outbreaks (varicella, mumps, and influenza-like illness) were detected and controlled successfully from April 1, 2012, to January 15, 2014. An impulse susceptible-exposed-infectious-recovered model was used to fit the epidemics of these three outbreaks. Moreover, it simulated the potential epidemics under interventions resulting from traditional surveillance signals. The effectiveness of the absenteeism-based control measures was evaluated by comparing the simulated datasets. The school absenteeism system generated 52 signals. Three outbreaks were verified through epidemiological investigation. Compared to traditional surveillance, the school absenteeism system generated simultaneous signals for the varicella outbreak, but 3 days in advance for the mumps outbreak and 2-4 days in advance for the influenza-like illness outbreak. The estimated excess protection rates of control measures based on early signals were 0.0%, 19.0-44.1%, and 29.0-37.0% for the three outbreaks, respectively. Although not all outbreak control measures can benefit from early signals through school absenteeism surveillance, the effectiveness of early signal-based interventions is obvious. School absenteeism surveillance plays an important role in reducing outbreak spread.
Effect of intervention on the control of Highly Pathogenic Avian Influenza in Nigeria.
Oladokun, Agnes Tinuke; Meseko, Clement Adebajo; Ighodalo, Edelokun; John, Benshak; Ekong, Pius Stephen
2012-01-01
The advent of HPAI in Nigeria was a traumatic experience for the poultry industry. Wealth and resources were lost to the ravages of the virus. The Government of Nigeria with the support of International donor agencies came up with a policy for the prevention of spread of the disease leading to the eventual control and eradication of the virus in Nigeria. The various measures implemented in the control of the outbreaks, and their effects on eradication of the virus in the country are highlighted. Using combined data from passive and active surveillance for HPAI in poultry farms, wetlands and live bird markets in Nigeria during 2006 - 2009, with laboratory diagnostic findings, we describe the characteristics of the control strategies implemented. The control measures include immediate reports of suspected outbreaks, prompt laboratory confirmation and rapid modified stamping out with compensations paid to affected farmers. Decontamination of infected farm premises, re-organization of live bird market were carried out, and bio security measures put in place before re-stocking. Three years following initial outbreak, the number of laboratory confirmed cases drastically reduced from 140 in 2006 and 160 in 2007 to only 2 cases of field outbreak in 2008. Only one case of human infection was documented during the period and no field outbreak or detection by surveillance was reported throughout 2009 and 2010. The measures employed by the Government through its agencies in the control of HPAI in Nigeria brought the incidence of the disease to naught.
[The application of the prospective space-time statistic in early warning of infectious disease].
Yin, Fei; Li, Xiao-Song; Feng, Zi-Jian; Ma, Jia-Qi
2007-06-01
To investigate the application of prospective space-time scan statistic in the early stage of detecting infectious disease outbreaks. The prospective space-time scan statistic was tested by mimicking daily prospective analyses of bacillary dysentery data of Chengdu city in 2005 (3212 cases in 102 towns and villages). And the results were compared with that of purely temporal scan statistic. The prospective space-time scan statistic could give specific messages both in spatial and temporal. The results of June indicated that the prospective space-time scan statistic could timely detect the outbreaks that started from the local site, and the early warning message was powerful (P = 0.007). When the merely temporal scan statistic for detecting the outbreak was sent two days later, and the signal was less powerful (P = 0.039). The prospective space-time scan statistic could make full use of the spatial and temporal information in infectious disease data and could timely and effectively detect the outbreaks that start from the local sites. The prospective space-time scan statistic could be an important tool for local and national CDC to set up early detection surveillance systems.
Torii, Manabu; Yin, Lanlan; Nguyen, Thang; Mazumdar, Chand T.; Liu, Hongfang; Hartley, David M.; Nelson, Noele P.
2014-01-01
Purpose Early detection of infectious disease outbreaks is crucial to protecting the public health of a society. Online news articles provide timely information on disease outbreaks worldwide. In this study, we investigated automated detection of articles relevant to disease outbreaks using machine learning classifiers. In a real-life setting, it is expensive to prepare a training data set for classifiers, which usually consists of manually labeled relevant and irrelevant articles. To mitigate this challenge, we examined the use of randomly sampled unlabeled articles as well as labeled relevant articles. Methods Naïve Bayes and Support Vector Machine (SVM) classifiers were trained on 149 relevant and 149 or more randomly sampled unlabeled articles. Diverse classifiers were trained by varying the number of sampled unlabeled articles and also the number of word features. The trained classifiers were applied to 15 thousand articles published over 15 days. Top-ranked articles from each classifier were pooled and the resulting set of 1337 articles was reviewed by an expert analyst to evaluate the classifiers. Results Daily averages of areas under ROC curves (AUCs) over the 15-day evaluation period were 0.841 and 0.836, respectively, for the naïve Bayes and SVM classifier. We referenced a database of disease outbreak reports to confirm that this evaluation data set resulted from the pooling method indeed covered incidents recorded in the database during the evaluation period. Conclusions The proposed text classification framework utilizing randomly sampled unlabeled articles can facilitate a cost-effective approach to training machine learning classifiers in a real-life Internet-based biosurveillance project. We plan to examine this framework further using larger data sets and using articles in non-English languages. PMID:21134784
Constructing Rigorous and Broad Biosurveillance Networks for Detecting Emerging Zoonotic Outbreaks
Brown, Mac; Moore, Leslie; McMahon, Benjamin; Powell, Dennis; LaBute, Montiago; Hyman, James M.; Rivas, Ariel; Jankowski, Mark; Berendzen, Joel; Loeppky, Jason; Manore, Carrie; Fair, Jeanne
2015-01-01
Determining optimal surveillance networks for an emerging pathogen is difficult since it is not known beforehand what the characteristics of a pathogen will be or where it will emerge. The resources for surveillance of infectious diseases in animals and wildlife are often limited and mathematical modeling can play a supporting role in examining a wide range of scenarios of pathogen spread. We demonstrate how a hierarchy of mathematical and statistical tools can be used in surveillance planning help guide successful surveillance and mitigation policies for a wide range of zoonotic pathogens. The model forecasts can help clarify the complexities of potential scenarios, and optimize biosurveillance programs for rapidly detecting infectious diseases. Using the highly pathogenic zoonotic H5N1 avian influenza 2006-2007 epidemic in Nigeria as an example, we determined the risk for infection for localized areas in an outbreak and designed biosurveillance stations that are effective for different pathogen strains and a range of possible outbreak locations. We created a general multi-scale, multi-host stochastic SEIR epidemiological network model, with both short and long-range movement, to simulate the spread of an infectious disease through Nigerian human, poultry, backyard duck, and wild bird populations. We chose parameter ranges specific to avian influenza (but not to a particular strain) and used a Latin hypercube sample experimental design to investigate epidemic predictions in a thousand simulations. We ranked the risk of local regions by the number of times they became infected in the ensemble of simulations. These spatial statistics were then complied into a potential risk map of infection. Finally, we validated the results with a known outbreak, using spatial analysis of all the simulation runs to show the progression matched closely with the observed location of the farms infected in the 2006-2007 epidemic. PMID:25946164
Miltgen, Guillaume; Bonnin, Rémy A; Avril, Catherine; Benoit-Cattin, Thierry; Martak, Daniel; Leclaire, Alexandre; Traversier, Nicolas; Roquebert, Bénédicte; Jaffar-Bandjee, Marie-Christine; Lugagne, Nathalie; Filleul, Laurent; Subiros, Marion; de Montera, Anne-Marie; Cholley, Pascal; Thouverez, Michelle; Dortet, Laurent; Bertrand, Xavier; Naas, Thierry; Hocquet, Didier; Belmonte, Olivier
2018-05-25
The spread of carbapenemase-producing Enterobacteriaceae (CPE) in the Southwest Indian Ocean islands is poorly known. We describe here an outbreak of colistin-resistant Enterobacter cloacae harboring bla IMI-1 in the French overseas department of Mayotte. Between October 2015 and January 2017, all isolates of imipenem-non-susceptible E. cloacae at the Mayotte Medical Center and University Hospital of Reunion Island were screened for carbapenemase production. Positive isolates were typed by pulsed-field gel electrophoresis and WGS-based MLST and all β-lactamase genes identified by PCR and sequencing. The resistance profiles were determined by agar diffusion and E-tests. Genetic support of the bla IMI-1 gene was determined by WGS. We detected 18 isolates of E.cloacae harboring the bla IMI-1 gene in 17 patients from Mayotte. PFGE analysis showed 16 of the 18 strains to be clonally-related and belonging to sequence type ST820. Based on clinical data, this outbreak most likely had a community origin. The bla IMI-1 gene in the 18 isolates was carried by a new variant of an integrative mobile element involving the Xer recombinases, called EcloIMEX-8. The mcr-1 to mcr-5 genes were absent from the collection. These isolates belong to E. cloacae cluster XI, known to be colistin heteroresistant. We report here the first outbreak of IMI-1-producing Enterobacteriaceae. IMI-1 producers may be under-detected in microbiology laboratories because of their unusual antibiotic resistance profile (resistant to imipenem, but with intermediate resistance to ertapenem and susceptible to extended-spectrum cephalosporins) and the absence of bla IMI-1 in the panel of genes targeted by molecular diagnostic kits. Copyright © 2018. Published by Elsevier B.V.
Preparedness of elderly long-term care facilities in HSE East for influenza outbreaks.
O'Connor, L; Boland, M; Murphy, H
2015-01-01
Abstract We assessed preparedness of HSE East elderly long-term care facilities for an influenza outbreak, and identified Public Health Department support needs. We surveyed 166 facilities based on the HSE checklist document for influenza outbreaks, with 58% response rate. Client flu vaccination rates were > 75%; leading barriers were client anxiety and consent issues. Target flu vaccine uptake of 40% in staff occurred in 43% of facilities and was associated with staff vaccine administration by afacility-attached GP (p = 0.035), having a facility outbreak plan (p = 0.013) and being anon-HSE run facility (p = 0.013). Leading barriers were staff personal anxiety (94%) and lack of awareness of the protective effect on clients (21%). Eighty-nine percent found Public Health helpful, and requested further educational support and advocacy. Staff vaccine uptake focus, organisational leadership, optimal vaccine provision models, outbreak plans and Public Health support are central to the influenza campaign in elderly long-term care facilities.
Le Strat, Yann
2017-01-01
The objective of this paper is to evaluate a panel of statistical algorithms for temporal outbreak detection. Based on a large dataset of simulated weekly surveillance time series, we performed a systematic assessment of 21 statistical algorithms, 19 implemented in the R package surveillance and two other methods. We estimated false positive rate (FPR), probability of detection (POD), probability of detection during the first week, sensitivity, specificity, negative and positive predictive values and F1-measure for each detection method. Then, to identify the factors associated with these performance measures, we ran multivariate Poisson regression models adjusted for the characteristics of the simulated time series (trend, seasonality, dispersion, outbreak sizes, etc.). The FPR ranged from 0.7% to 59.9% and the POD from 43.3% to 88.7%. Some methods had a very high specificity, up to 99.4%, but a low sensitivity. Methods with a high sensitivity (up to 79.5%) had a low specificity. All methods had a high negative predictive value, over 94%, while positive predictive values ranged from 6.5% to 68.4%. Multivariate Poisson regression models showed that performance measures were strongly influenced by the characteristics of time series. Past or current outbreak size and duration strongly influenced detection performances. PMID:28715489
Ambagala, A; Fisher, M; Goolia, M; Nfon, C; Furukawa-Stoffer, T; Ortega Polo, R; Lung, O
2017-10-01
Foot-and-mouth disease (FMD) is a highly contagious viral disease of cloven-hoofed animals, which can decimate the livestock industry and economy of countries previously free of this disease. Rapid detection of foot-and-mouth disease virus (FMDV) is critical to containing an FMD outbreak. Availability of a rapid, highly sensitive and specific, yet simple and field-deployable assay would support local decision-making during an FMDV outbreak. Here we report validation of a novel reverse transcription-insulated isothermal PCR (RT-iiPCR) assay that can be performed on a commercially available, compact and portable POCKIT ™ analyser that automatically analyses data and displays '+' or '-' results. The FMDV RT-iiPCR assay targets the 3D region of the FMDV genome and was capable of detecting 9 copies of in vitro-transcribed RNA standard with 95% confidence. It accurately identified 63 FMDV strains belonging to all seven serotypes and showed no cross-reactivity with viruses causing similar clinical diseases in cloven-hoofed animals. The assay was able to identify FMDV RNA in multiple sample types including oral, nasal and lesion swabs, epithelial tissue suspensions, vesicular and oral fluid samples, even before the appearance of clinical signs. Clinical sensitivity of the assay was comparable or slightly higher than the laboratory-based real-time RT-PCR assay in use. The assay was able to detect FMDV RNA in vesicular fluid samples without nucleic acid extraction. For RNA extraction from more complex sample types, a commercially available taco ™ mini transportable magnetic bead-based, automated extraction system was used. This assay provides a potentially useful field-deployable diagnostic tool for rapid detection of FMDV in an outbreak in FMD-free countries or for routine diagnostics in endemic countries with less structured laboratory systems. © 2016 Her Majesty the Queen in Right of Canada.
Yu, Pengbo; Ma, Chaofeng; Nawaz, Muhammad; Han, Lei; Zhang, Jianfang; Du, Quanli; Zhang, Lixia; Feng, Qunling; Wang, Jingjun; Xu, Jiru
2013-08-01
Outbreaks of ARD associated with HAdV have been reported in military populations in many countries. Here, we report an ARD outbreak caused by HAdV-7 in a military training camp in Shaanxi Province, China, from February to March of 2012. Epidemic data and samples from the patients were collected, and viral nucleotides from samples and viral isolations were detected and sequenced. IgG and IgA antibodies against HAdV, and the neutralization antibodies against the viral strain isolated in this outbreak, were detected. Epidemiological study showed that all personnel affected were males with an average age of 19.1 years. Two peaks appeared on the epicurve and there was an 8-day interval between peaks. Laboratory results of viral nucleotide detection carried out with clinical specimens were positive for HAdV (83.33%, 15/18). Further study through serum antibody assay, virus isolation and phylogenetic analysis showed that HAdV-7 was the etiological agent responsible for the outbreak. IgA antibody began to appear on the 4th day after the onset and showed 100% positivity on the 8th day. The virus strain in the present outbreak was highly similar to the virus isolated in Hanzhong Shaanxi in 2009. We conclude that HAdV-7 was the pathogen corresponding to the outbreak, and this is the first report of an ARD outbreak caused by HAdV-7 in military persons in China. Vaccine development, as well as enhanced epidemiological and virological surveillance of HAdV infections in China should be emphasized. © 2013 The Societies and Wiley Publishing Asia Pty Ltd.
Jackson, Brendan R; Tarr, Cheryl; Strain, Errol; Jackson, Kelly A; Conrad, Amanda; Carleton, Heather; Katz, Lee S; Stroika, Steven; Gould, L Hannah; Mody, Rajal K; Silk, Benjamin J; Beal, Jennifer; Chen, Yi; Timme, Ruth; Doyle, Matthew; Fields, Angela; Wise, Matthew; Tillman, Glenn; Defibaugh-Chavez, Stephanie; Kucerova, Zuzana; Sabol, Ashley; Roache, Katie; Trees, Eija; Simmons, Mustafa; Wasilenko, Jamie; Kubota, Kristy; Pouseele, Hannes; Klimke, William; Besser, John; Brown, Eric; Allard, Marc; Gerner-Smidt, Peter
2016-08-01
Listeria monocytogenes (Lm) causes severe foodborne illness (listeriosis). Previous molecular subtyping methods, such as pulsed-field gel electrophoresis (PFGE), were critical in detecting outbreaks that led to food safety improvements and declining incidence, but PFGE provides limited genetic resolution. A multiagency collaboration began performing real-time, whole-genome sequencing (WGS) on all US Lm isolates from patients, food, and the environment in September 2013, posting sequencing data into a public repository. Compared with the year before the project began, WGS, combined with epidemiologic and product trace-back data, detected more listeriosis clusters and solved more outbreaks (2 outbreaks in pre-WGS year, 5 in WGS year 1, and 9 in year 2). Whole-genome multilocus sequence typing and single nucleotide polymorphism analyses provided equivalent phylogenetic relationships relevant to investigations; results were most useful when interpreted in context of epidemiological data. WGS has transformed listeriosis outbreak surveillance and is being implemented for other foodborne pathogens. Published by Oxford University Press for the Infectious Diseases Society of America 2016. This work is written by (a) US Government employee(s) and is in the public domain in the US.
Effects of gypsy moth outbreaks on North American woodpeckers
Walter D. Koenig; Eric L. Walters; Andrew M. Liebhold
2011-01-01
We examined the effects of the introduced gypsy moth (Lymantria dispar) on seven species of North American woodpeckers by matching spatially explicit data on gypsy moth outbreaks with data on breeding and wintering populations. In general, we detected modest effects during outbreaks: during the breeding season one species, the Red-headed Woodpecker...
USDA-ARS?s Scientific Manuscript database
Introduction: Advances in genomic technologies have improve the speed and precision of foodborne disease outbreak detection and response. For the past two decades, pulsed field gel electrophoresis (PFGE) has been the method of choice for surveillance and outbreak investigation with foodborne pathoge...
Birkhead, G; Vogt, R L; Heun, E M; Snyder, J T; McClane, B A
1988-01-01
Published criteria for implicating Clostridium perfringens as the cause of food-poisoning outbreaks include finding a median fecal C. perfringens spore count of greater than 10(6)/g among specimens from ill persons. We investigated a food-poisoning outbreak with the epidemiologic characteristics of C. perfringens-related disease in a nursing home in which the median fecal spore count for ill patients (2.5 X 10(7)/g) was similar to that for well patients (4.0 X 10(6)/g), making the etiology of the outbreak uncertain. All ill and well patients tested had eaten turkey, the implicated food item. C. perfringens enterotoxin was detected by reverse passive latex agglutination in fecal specimens from six of six ill and none of four well patients who had eaten turkey (P = 0.005), suggesting that this organism had caused the outbreak. This investigation suggests that detection of fecal C. perfringens enterotoxin is a specific way to identify this organism as the causative agent in food-poisoning outbreaks. PMID:2895776
Halbedel, Sven; Prager, Rita; Fuchs, Stephan; Trost, Eva; Werner, Guido; Flieger, Antje
2018-06-01
Listeria monocytogenes causes foodborne outbreaks with high mortality. For improvement of outbreak cluster detection, the German consiliary laboratory for listeriosis implemented whole-genome sequencing (WGS) in 2015. A total of 424 human L. monocytogenes isolates collected in 2007 to 2017 were subjected to WGS and core-genome multilocus sequence typing (cgMLST). cgMLST grouped the isolates into 38 complexes, reflecting 4 known and 34 unknown disease clusters. Most of these complexes were confirmed by single nucleotide polymorphism (SNP) calling, but some were further differentiated. Interestingly, several cgMLST cluster types were further subtyped by pulsed-field gel electrophoresis, partly due to phage insertions in the accessory genome. Our results highlight the usefulness of cgMLST for routine cluster detection but also show that cgMLST complexes require validation by methods providing higher typing resolution. Twelve cgMLST clusters included recent cases, suggesting activity of the source. Therefore, the cgMLST nomenclature data presented here may support future public health actions. Copyright © 2018 American Society for Microbiology.
Onyango, Laura A.; Quinn, Chloe; Tng, Keng H.; Wood, James G.; Leslie, Greg
2015-01-01
Potable reuse is implemented in several countries around the world to augment strained water supplies. This article presents a public health perspective on potable reuse by comparing the critical infrastructure and institutional capacity characteristics of two well-established potable reuse schemes with conventional drinking water schemes in developed nations that have experienced waterborne outbreaks. Analysis of failure events in conventional water systems between 2003 and 2013 showed that despite advances in water treatment technologies, drinking water outbreaks caused by microbial contamination were still frequent in developed countries and can be attributed to failures in infrastructure or institutional practices. Numerous institutional failures linked to ineffective treatment protocols, poor operational practices, and negligence were detected. In contrast, potable reuse schemes that use multiple barriers, online instrumentation, and operational measures were found to address the events that have resulted in waterborne outbreaks in conventional systems in the past decade. Syndromic surveillance has emerged as a tool in outbreak detection and was useful in detecting some outbreaks; increases in emergency department visits and GP consultations being the most common data source, suggesting potential for an increasing role in public health surveillance of waterborne outbreaks. These results highlight desirable characteristics of potable reuse schemes from a public health perspective with potential for guiding policy on surveillance activities. PMID:27053920
Onyango, Laura A; Quinn, Chloe; Tng, Keng H; Wood, James G; Leslie, Greg
2015-01-01
Potable reuse is implemented in several countries around the world to augment strained water supplies. This article presents a public health perspective on potable reuse by comparing the critical infrastructure and institutional capacity characteristics of two well-established potable reuse schemes with conventional drinking water schemes in developed nations that have experienced waterborne outbreaks. Analysis of failure events in conventional water systems between 2003 and 2013 showed that despite advances in water treatment technologies, drinking water outbreaks caused by microbial contamination were still frequent in developed countries and can be attributed to failures in infrastructure or institutional practices. Numerous institutional failures linked to ineffective treatment protocols, poor operational practices, and negligence were detected. In contrast, potable reuse schemes that use multiple barriers, online instrumentation, and operational measures were found to address the events that have resulted in waterborne outbreaks in conventional systems in the past decade. Syndromic surveillance has emerged as a tool in outbreak detection and was useful in detecting some outbreaks; increases in emergency department visits and GP consultations being the most common data source, suggesting potential for an increasing role in public health surveillance of waterborne outbreaks. These results highlight desirable characteristics of potable reuse schemes from a public health perspective with potential for guiding policy on surveillance activities.
Gallimore, C I; Barreiros, M A B; Brown, D W G; Nascimento, J P; Leite, J P G
2004-03-01
Noroviruses (Norwalk-like viruses) are an important cause of gastroenteritis worldwide. They are the most common cause of outbreaks of gastroenteritis in the adult population and occur in nursing homes for the elderly, geriatric wards, medical wards, and in hotel and restaurant settings. Food-borne outbreaks have also occurred following consumption of contaminated oysters. This study describes the application of a reverse transcription-polymerase chain reaction (RT-PCR) assay using random primers (PdN6) and specific Ni and E3 primers, directed at a small region of the RNA-dependent RNA polymerase-coding region of the norovirus genome, and DNA sequencing for the detection and preliminary characterisation of noroviruses in outbreaks of gastroenteritis in children in Brazil. The outbreak samples were collected from children <5 years of age at the Bertha Lutz children's day care facility at Oswaldo Cruz Foundation (Fiocruz), Rio de Janeiro, that occurred between 1996 and 1998, where no pathogen had been identified. At the Bertha Lutz day care center facility, only Fiocruz's employee children are provided for, and they come from different social, economic and cultural backgrounds. Three distinct genogroup II strains were detected in three outbreaks in 1997/98 and were most closely related to genotypes GII-3 (Mexico virus) and GII-4 (Grimsby virus), both of which have been detected in paediatric and adult outbreaks of gastroenteritis worldwide.
First detection of foot-and-mouth disease virus O/Ind-2001d in Vietnam.
Vu, Le T; Long, Ngo T; Brito, Barbara; Stenfeldt, Carolina; Phuong, Nguyen T; Hoang, Bui H; Pauszek, Steven J; Hartwig, Ethan J; Smoliga, George R; Vu, Pham P; Quang, Le T V; Hung, Vo V; Tho, Nguyen D; Dong, Pham V; Minh, Phan Q; Bertram, Miranda; Fish, Ian H; Rodriguez, Luis L; Dung, Do H; Arzt, Jonathan
2017-01-01
In recent years, foot-and-mouth disease virus (FMDV) serotype O, topotype Middle East-South Asia (ME-SA), lineage Ind-2001d has spread from the Indian subcontinent to the Middle East, North Africa, and Southeast Asia. In the current report, we describe the first detection of this lineage in Vietnam in May, 2015 in Đắk Nông province. Three subsequent outbreaks caused by genetically related viruses occurred between May-October, 2015 after which the virus was not detected in clinical outbreaks for at least 15 subsequent months. The observed outbreaks affected (in chronological order): cattle in Đắk Nông province, pigs in Đắk Lắk province and Đắk Nông province, and cattle in Ninh Thuận province. The clinical syndromes associated with these outbreaks were consistent with typical FMD in the affected species. Overall attack rate on affected premises was 0.85 in pigs and 0.93 in cattle over the course of the outbreak. Amongst 378 pigs at risk on affected premises, 85 pigs died during the outbreaks; there were no deaths among cattle. The manner in which FMDV/O/ME-SA/Ind-2001d was introduced into Vietnam remains undetermined; however, movement of live cattle is the suspected route. This incursion has substantial implications for epidemiology and control of FMD in Southeast Asia.
Listeriosis Outbreaks and Associated Food Vehicles, United States, 1998–2008
Cartwright, Emily J.; Jackson, Kelly A.; Johnson, Shacara D.; Graves, Lewis M.; Mahon, Barbara E.
2013-01-01
Listeria monocytogenes, a bacterial foodborne pathogen, can cause meningitis, bacteremia, and complications during pregnancy. This report summarizes listeriosis outbreaks reported to the Foodborne Disease Outbreak Surveillance System of the Centers for Disease Control and Prevention during 1998–2008. The study period includes the advent of PulseNet (a national molecular subtyping network for outbreak detection) in 1998 and the Listeria Initiative (enhanced surveillance for outbreak investigation) in 2004. Twenty-four confirmed listeriosis outbreaks were reported during 1998–2008, resulting in 359 illnesses, 215 hospitalizations, and 38 deaths. Outbreaks earlier in the study period were generally larger and longer. Serotype 4b caused the largest number of outbreaks and outbreak-associated cases. Ready-to-eat meats caused more early outbreaks, and novel vehicles (i.e., sprouts, taco/nacho salad) were associated with outbreaks later in the study period. These changes may reflect the effect of PulseNet and the Listeria Initiative and regulatory initiatives designed to prevent contamination in ready-to-eat meat and poultry products. PMID:23260661
Representativeness of Tuberculosis Genotyping Surveillance in the United States, 2009-2010.
Shak, Emma B; France, Anne Marie; Cowan, Lauren; Starks, Angela M; Grant, Juliana
2015-01-01
Genotyping of Mycobacterium tuberculosis isolates contributes to tuberculosis (TB) control through detection of possible outbreaks. However, 20% of U.S. cases do not have an isolate for testing, and 10% of cases with isolates do not have a genotype reported. TB outbreaks in populations with incomplete genotyping data might be missed by genotyping-based outbreak detection. Therefore, we assessed the representativeness of TB genotyping data by comparing characteristics of cases reported during January 1, 2009-December 31, 2010, that had a genotype result with those cases that did not. Of 22,476 cases, 14,922 (66%) had a genotype result. Cases without genotype results were more likely to be patients <19 years of age, with unknown HIV status, of female sex, U.S.-born, and with no recent history of homelessness or substance abuse. Although cases with a genotype result are largely representative of all reported U.S. TB cases, outbreak detection methods that rely solely on genotyping data may underestimate TB transmission among certain groups.
Representativeness of Tuberculosis Genotyping Surveillance in the United States, 2009–2010
Shak, Emma B.; Cowan, Lauren; Starks, Angela M.; Grant, Juliana
2015-01-01
Genotyping of Mycobacterium tuberculosis isolates contributes to tuberculosis (TB) control through detection of possible outbreaks. However, 20% of U.S. cases do not have an isolate for testing, and 10% of cases with isolates do not have a genotype reported. TB outbreaks in populations with incomplete genotyping data might be missed by genotyping-based outbreak detection. Therefore, we assessed the representativeness of TB genotyping data by comparing characteristics of cases reported during January 1, 2009–December 31, 2010, that had a genotype result with those cases that did not. Of 22,476 cases, 14,922 (66%) had a genotype result. Cases without genotype results were more likely to be patients <19 years of age, with unknown HIV status, of female sex, U.S.-born, and with no recent history of homelessness or substance abuse. Although cases with a genotype result are largely representative of all reported U.S. TB cases, outbreak detection methods that rely solely on genotyping data may underestimate TB transmission among certain groups. PMID:26556930
Jones, Timothy F; Sashti, Nupur; Ingram, Amanda; Phan, Quyen; Booth, Hillary; Rounds, Joshua; Nicholson, Cyndy S; Cosgrove, Shaun; Crocker, Kia; Gould, L Hannah
2016-12-01
Molecular subtyping of pathogens is critical for foodborne disease outbreak detection and investigation. Many clusters initially identified by pulsed-field gel electrophoresis (PFGE) are not confirmed as point-source outbreaks. We evaluated characteristics of clusters that can help prioritize investigations to maximize effective use of limited resources. A multiagency collaboration (FoodNet) collected data on Salmonella and Escherichia coli O157 clusters for 3 years. Cluster size, timing, extent, and nature of epidemiologic investigations were analyzed to determine associations with whether the cluster was identified as a confirmed outbreak. During the 3-year study period, 948 PFGE clusters were identified; 849 (90%) were Salmonella and 99 (10%) were E. coli O157. Of those, 192 (20%) were ultimately identified as outbreaks (154 [18%] of Salmonella and 38 [38%] of E. coli O157 clusters). Successful investigation was significantly associated with larger cluster size, more rapid submission of isolates (e.g., for Salmonella, 6 days for outbreaks vs. 8 days for nonoutbreaks) and PFGE result reporting to investigators (16 days vs. 29 days, respectively), and performance of analytic studies (completed in 33% of Salmonella outbreaks vs. 1% of nonoutbreaks) and environmental investigations (40% and 1%, respectively). Intervals between first and second cases in a cluster did not differ significantly between outbreaks and nonoutbreaks. Molecular subtyping of pathogens is a rapidly advancing technology, and successfully identifying outbreaks will vary by pathogen and methods used. Understanding criteria for successfully investigating outbreaks is critical for efficiently using limited resources.
Fan, Yunzhou; Yang, Mei; Jiang, Hongbo; Wang, Ying; Yang, Wenwen; Zhang, Zhixia; Yan, Weirong; Diwan, Vinod K.; Xu, Biao; Dong, Hengjin; Palm, Lars; Liu, Li; Nie, Shaofa
2014-01-01
Background School absenteeism is a common data source in syndromic surveillance, which allows for the detection of outbreaks at an early stage. Previous studies focused on its correlation with other data sources. In this study, we evaluated the effectiveness of control measures based on early warning signals from school absenteeism surveillance in rural Chinese schools. Methods A school absenteeism surveillance system was established in all 17 primary schools in 3 adjacent towns in the Chinese region of Hubei. Three outbreaks (varicella, mumps, and influenza-like illness) were detected and controlled successfully from April 1, 2012, to January 15, 2014. An impulse susceptible-exposed-infectious-recovered model was used to fit the epidemics of these three outbreaks. Moreover, it simulated the potential epidemics under interventions resulting from traditional surveillance signals. The effectiveness of the absenteeism-based control measures was evaluated by comparing the simulated datasets. Results The school absenteeism system generated 52 signals. Three outbreaks were verified through epidemiological investigation. Compared to traditional surveillance, the school absenteeism system generated simultaneous signals for the varicella outbreak, but 3 days in advance for the mumps outbreak and 2–4 days in advance for the influenza-like illness outbreak. The estimated excess protection rates of control measures based on early signals were 0.0%, 19.0–44.1%, and 29.0–37.0% for the three outbreaks, respectively. Conclusions Although not all outbreak control measures can benefit from early signals through school absenteeism surveillance, the effectiveness of early signal-based interventions is obvious. School absenteeism surveillance plays an important role in reducing outbreak spread. PMID:25250786
Selection tool for foodborne norovirus outbreaks.
Verhoef, Linda P B; Kroneman, Annelies; van Duynhoven, Yvonne; Boshuizen, Hendriek; van Pelt, Wilfrid; Koopmans, Marion
2009-01-01
Detection of pathogens in the food chain is limited mainly to bacteria, and the globalization of the food industry enables international viral foodborne outbreaks to occur. Outbreaks from 2002 through 2006 recorded in a European norovirus surveillance database were investigated for virologic and epidemiologic indicators of food relatedness. The resulting validated multivariate logistic regression model comparing foodborne (n = 224) and person-to-person (n = 654) outbreaks was used to create a practical web-based tool that can be limited to epidemiologic parameters for nongenotyping countries. Non-genogroup-II.4 outbreaks, higher numbers of cases, and outbreaks in restaurants or households characterized (sensitivity = 0.80, specificity = 0.86) foodborne outbreaks and reduced the percentage of outbreaks requiring source-tracing to 31%. The selection tool enabled prospectively focused follow-up. Use of this tool is likely to improve data quality and strain typing in current surveillance systems, which is necessary for identification of potential international foodborne outbreaks.
Coccidioidomycosis Outbreaks, United States and Worldwide, 1940-2015.
Freedman, Michael; Jackson, Brendan R; McCotter, Orion; Benedict, Kaitlin
2018-03-01
Coccidioidomycosis causes substantial illness and death in the United States each year. Although most cases are sporadic, outbreaks provide insight into the clinical and environmental features of coccidioidomycosis, high-risk activities, and the geographic range of Coccidioides fungi. We identified reports published in English of 47 coccidioidomycosis outbreaks worldwide that resulted in 1,464 cases during 1940-2015. Most (85%) outbreaks were associated with environmental exposures; the 2 largest outbreaks resulted from an earthquake and a large dust storm. More than one third of outbreaks occurred in areas where the fungus was not previously known to be endemic, and more than half of outbreaks involved occupational exposures. Coccidioidomycosis outbreaks can be difficult to detect and challenging to prevent given the unknown effectiveness of environmental control methods and personal protective equipment; therefore, increased awareness of coccidioidomycosis outbreaks is needed among public health professionals, healthcare providers, and the public.
Coccidioidomycosis Outbreaks, United States and Worldwide, 1940–2015
Freedman, Michael; Jackson, Brendan R.; McCotter, Orion
2018-01-01
Coccidioidomycosis causes substantial illness and death in the United States each year. Although most cases are sporadic, outbreaks provide insight into the clinical and environmental features of coccidioidomycosis, high-risk activities, and the geographic range of Coccidioides fungi. We identified reports published in English of 47 coccidioidomycosis outbreaks worldwide that resulted in 1,464 cases during 1940–2015. Most (85%) outbreaks were associated with environmental exposures; the 2 largest outbreaks resulted from an earthquake and a large dust storm. More than one third of outbreaks occurred in areas where the fungus was not previously known to be endemic, and more than half of outbreaks involved occupational exposures. Coccidioidomycosis outbreaks can be difficult to detect and challenging to prevent given the unknown effectiveness of environmental control methods and personal protective equipment; therefore, increased awareness of coccidioidomycosis outbreaks is needed among public health professionals, healthcare providers, and the public. PMID:29460741
[Outbreaks of acute gastroenteritis caused by small round structured viruses in Tokyo].
Sekine, S; Hayashi, Y; Ando, T; Ohta, K; Miki, T; Okada, S
1992-07-01
Of 34 non-bacterial gastroenteritis outbreaks which occurred at day-care centers, kindergartens, elementary and secondary schools in Tokyo during the period from February 1985 to June 1991, 28 outbreaks from which small round structured viruses (SRSV) were detected in the patients' stool specimens by electron microscopy were subjected to an epidemiological investigation. The outbreaks tended to occur frequently in the cold season; twenty-two (79%) of these outbreaks from November through April. Though detailed epidemiological informations was not obtained from all outbreaks, the common source of infection were presumed to be present in many of the outbreaks, judged from the incidence as to time course of patients. Food doubted to be incriminated as transmission vehicles in these outbreaks was served at schools, kindergartens, and lodgings. In some outbreaks, SRSV was detected from stool specimens of food handlers, or they were seroconverted to SRSV, suggesting that food was incriminated as a transmission vehicle. The symptoms of patients differ slightly from age to age: in the age range of 0 to 6 years, vomiting 90%, fever 41% and diarrhea 32%; in the 6 to 12 year-olds, nausea 61%, vomiting 48%, abdominal pain 65%, diarrhea 20% and fever 29%; and in the 12 to 15 year-olds, nausea 69%, vomiting 42%, abdominal pain 60%, diarrhea 30% and fever 34%. The lower the age of patient vomiting was more frequently observed. In these lower age groups, the frequency of nausea and vomiting tended to exceed that of diarrhea.
Mürmann, Lisandra; dos Santos, Maria Cecília; Longaray, Solange Mendes; Both, Jane Mari Corrêa; Cardoso, Marisa
2008-01-01
Data concerning the prevalence and populations of Salmonella in foods implicated in outbreaks may be important to the development of quantitative microbial risk assessments of individual food products. In this sense, the objective of the present study was to assess the amount of Salmonella sp. in different foods implicated in foodborne outbreaks in Rio Grande do Sul occurred in 2005 and to characterize the isolated strains using phenotypic and genotypic methods. Nineteen food samples involved in ten foodborne outbreaks occurred in 2005, and positive on Salmonella isolation at the Central Laboratory of the Health Department of the State of Rio Grande do Sul, were included in this study. Food samples were submitted to estimation of Salmonella using the Most Probable Number (MPN) technique. Moreover, one confirmed Salmonella colony of each food sample was serotyped, characterized by its XbaI-macrorestriction profile, and submitted to antimicrobial resistance testing. Foods containing eggs, mayonnaise or chicken were contaminated with Salmonella in eight outbreaks. Higher counts (>107 MPN.g-1) of Salmonella were detected mostly in foods containing mayonnaise. The isolation of Salmonella from multiple food items in five outbreaks probably resulted from the cross-contamination, and the high Salmonella counts detected in almost all analyzed samples probably resulted from storing in inadequate temperature. All strains were identified as S. Enteritidis, and presented a unique macrorestriction profile, demonstrating the predominance of one clonal group in foods involved in the salmonellosis outbreaks. A low frequency of antimicrobial resistant S. Enteritidis strains was observed and nalidixic acid was the only resistance marker detected. PMID:24031261
Genton, Céline; Cristescu, Romane; Gatti, Sylvain; Levréro, Florence; Bigot, Elodie; Motsch, Peggy; Le Gouar, Pascaline; Pierre, Jean-Sébastien; Ménard, Nelly
2017-09-01
Demographic crashes due to emerging diseases can contribute to population fragmentation and increase extinction risk of small populations. Ebola outbreaks in 2002-2004 are suspected to have caused a decline of more than 80% in some Western lowland gorilla (Gorilla gorilla gorilla) populations. We investigated whether demographic indicators of this event allowed for the detection of spatial fragmentation in gorilla populations. We collected demographic data from two neighbouring populations: the Lokoué population, suspected to have been affected by an Ebola outbreak (followed from 2001 to 2014), and the Romani population, of unknown demographic status before Ebola outbreaks (followed from 2005 to 2014). Ten years after the outbreak, the Lokoué population is slowly recovering and the short-term demographic indicators of a population crash were no longer detectable. The Lokoué population has not experienced any additional demographic perturbation over the past decade. The Romani population did not show any of the demographic indicators of a population crash over the past decade. Its demographic structure remained similar to that of unaffected populations. Our results highlighted that the Ebola disease could contribute to fragmentation of gorilla populations due to the spatially heterogeneous impact of its outbreaks. The demographic structure of populations (i.e., age-sex and group structure) can be useful indicators of a possible occurrence of recent Ebola outbreaks in populations without known history, and may be more broadly used in other emerging disease/species systems. Longitudinal data are critical to our understanding of the impact of emerging diseases on wild populations and their conservation. © 2017 Wiley Periodicals, Inc.
García Ramírez, Dolores; Nicola, Federico; Zarate, Soledad; Relloso, Silvia; Smayevsky, Jorgelina; Arduino, Sonia
2013-10-01
An outbreak of Klebsiella pneumoniae carbapenamase (KPC)-producing K. pneumoniae occurred at our institution. Multiresistant Pseudomonas aeruginosa could have acquired this transmissible resistance mechanism, going unnoticed because its phenotypic detection in this species is difficult. We compared P. aeruginosa isolates obtained before and after the KPC-producing K. pneumoniae outbreak. No bla(KPC) genes were detected in the isolates obtained before the outbreak, whereas 33/76 (43%) of the isolates obtained after the outbreak harboured the bla(KPC) gene. P. aeruginosa may thus become a reservoir of this transmissible resistance mechanism. It is very important to understand the epidemiology of these multiresistant isolates, in order to achieve early implementation of adequate control measures to contain and reduce their dissemination in the hospital environment.
A new prior for bayesian anomaly detection: application to biosurveillance.
Shen, Y; Cooper, G F
2010-01-01
Bayesian anomaly detection computes posterior probabilities of anomalous events by combining prior beliefs and evidence from data. However, the specification of prior probabilities can be challenging. This paper describes a Bayesian prior in the context of disease outbreak detection. The goal is to provide a meaningful, easy-to-use prior that yields a posterior probability of an outbreak that performs at least as well as a standard frequentist approach. If this goal is achieved, the resulting posterior could be usefully incorporated into a decision analysis about how to act in light of a possible disease outbreak. This paper describes a Bayesian method for anomaly detection that combines learning from data with a semi-informative prior probability over patterns of anomalous events. A univariate version of the algorithm is presented here for ease of illustration of the essential ideas. The paper describes the algorithm in the context of disease-outbreak detection, but it is general and can be used in other anomaly detection applications. For this application, the semi-informative prior specifies that an increased count over baseline is expected for the variable being monitored, such as the number of respiratory chief complaints per day at a given emergency department. The semi-informative prior is derived based on the baseline prior, which is estimated from using historical data. The evaluation reported here used semi-synthetic data to evaluate the detection performance of the proposed Bayesian method and a control chart method, which is a standard frequentist algorithm that is closest to the Bayesian method in terms of the type of data it uses. The disease-outbreak detection performance of the Bayesian method was statistically significantly better than that of the control chart method when proper baseline periods were used to estimate the baseline behavior to avoid seasonal effects. When using longer baseline periods, the Bayesian method performed as well as the control chart method. The time complexity of the Bayesian algorithm is linear in the number of the observed events being monitored, due to a novel, closed-form derivation that is introduced in the paper. This paper introduces a novel prior probability for Bayesian outbreak detection that is expressive, easy-to-apply, computationally efficient, and performs as well or better than a standard frequentist method.
... on Facebook Tweet Share Compartir Disease detectives collecting soil samples to test for fungus When fungal disease ... a hydroelectric dam Source: related to disruption of soil contaminated with bat droppings Outbreak investigation partners: Dominican ...
Big Data and the Global Public Health Intelligence Network (GPHIN)
Dion, M; AbdelMalik, P; Mawudeku, A
2015-01-01
Background Globalization and the potential for rapid spread of emerging infectious diseases have heightened the need for ongoing surveillance and early detection. The Global Public Health Intelligence Network (GPHIN) was established to increase situational awareness and capacity for the early detection of emerging public health events. Objective To describe how the GPHIN has used Big Data as an effective early detection technique for infectious disease outbreaks worldwide and to identify potential future directions for the GPHIN. Findings Every day the GPHIN analyzes over more than 20,000 online news reports (over 30,000 sources) in nine languages worldwide. A web-based program aggregates data based on an algorithm that provides potential signals of emerging public health events which are then reviewed by a multilingual, multidisciplinary team. An alert is sent out if a potential risk is identified. This process proved useful during the Severe Acute Respiratory Syndrome (SARS) outbreak and was adopted shortly after by a number of countries to meet new International Health Regulations that require each country to have the capacity for early detection and reporting. The GPHIN identified the early SARS outbreak in China, was credited with the first alert on MERS-CoV and has played a significant role in the monitoring of the Ebola outbreak in West Africa. Future developments are being considered to advance the GPHIN’s capacity in light of other Big Data sources such as social media and its analytical capacity in terms of algorithm development. Conclusion The GPHIN’s early adoption of Big Data has increased global capacity to detect international infectious disease outbreaks and other public health events. Integration of additional Big Data sources and advances in analytical capacity could further strengthen the GPHIN’s capability for timely detection and early warning. PMID:29769954
Early warning system for Douglas-fir tussock moth outbreaks in the Western United States.
Gary E. Daterman; John M. Wenz; Katharine A. Sheehan
2004-01-01
The Early Warning System is a pheromone-based trapping system used to detect outbreaks of Douglas-fir tussock moth (DFTM, Orgyia pseudotsugata) in the western United States. Millions of acres are susceptible to DFTM defoliation, but Early Warning System monitoring focuses attention only on the relatively limited areas where outbreaks may be...
Measles Cases during Ebola Outbreak, West Africa, 2013-2106.
Colavita, Francesca; Biava, Mirella; Castilletti, Concetta; Quartu, Serena; Vairo, Francesco; Caglioti, Claudia; Agrati, Chiara; Lalle, Eleonora; Bordi, Licia; Lanini, Simone; Guanti, Michela Delli; Miccio, Rossella; Ippolito, Giuseppe; Capobianchi, Maria R; Di Caro, Antonino
2017-06-01
The recent Ebola outbreak in West Africa caused breakdowns in public health systems, which might have caused outbreaks of vaccine-preventable diseases. We tested 80 patients admitted to an Ebola treatment center in Freetown, Sierra Leone, for measles. These patients were negative for Ebola virus. Measles virus IgM was detected in 13 (16%) of the patients.
ERIC Educational Resources Information Center
Rogers, James W.; Cox, James R.
2008-01-01
At RMIT University, students may now elect to study infectious diseases through a course called Outbreak--The Detection and Control of Infectious Disease. Outbreak was designed to simulate in an online class the effective teamwork required to bring resolution to outbreak crises and enable frameworks for future prevention. The appropriateness of…
Jericó Alba, C; Nogués Solán, X; Santos Martínez, M J; Félez Flor, M; Garcés Jarque, J M; Mariñosa Marré, M; Sanz Salvador, X
2004-02-01
Clinical and microbiological descriptive analysis of the outbreak of community legionnaire's disease recorded in the Barcelona's Barcelonesa neighborhood in November 2000. Retrospective review of the epidemiological and clinical manifestations, as well as the evolution of the cases of Legionella pneumophila pneumonia associated with the outbreak and cared of in the Hospital del Mar. The 48 patients evaluated, all of them with confirmed diagnoses, represent 89% of the cases communicated. Seventy-five percent of patients showed some underlying disease, 54% had some criterion for severity, and mortality was 4%. In 81% of cases the detection of the antigen of Legionella pneumophila in urine was the diagnostic method. The detection in urine of the Legionella pneumophila antigen makes possible the early diagnosis of legionnaire's disease, particularly in epidemic outbreaks, which that facilitates the fast establishment of the adequate treatment and contributes to the reduction in mortality even in patients of high risk.
Baer, Atar; Elbert, Yevgeniy; Burkom, Howard S; Holtry, Rekha; Lombardo, Joseph S; Duchin, Jeffrey S
2011-03-01
We evaluated emergency department (ED) data, emergency medical services (EMS) data, and public utilities data for describing an outbreak of carbon monoxide (CO) poisoning following a windstorm. Syndromic ED data were matched against previously collected chart abstraction data. We ran detection algorithms on selected time series derived from all 3 data sources to identify health events associated with the CO poisoning outbreak. We used spatial and spatiotemporal scan statistics to identify geographic areas that were most heavily affected by the CO poisoning event. Of the 241 CO cases confirmed by chart review, 190 (78.8%) were identified in the syndromic surveillance data as exact matches. Records from the ED and EMS data detected an increase in CO-consistent syndromes after the storm. The ED data identified significant clusters of CO-consistent syndromes, including zip codes that had widespread power outages. Weak temporal gastrointestinal (GI) signals, possibly resulting from ingestion of food spoiled by lack of refrigeration, were detected in the ED data but not in the EMS data. Spatial clustering of GI-based groupings in the ED data was not detected. Data from this evaluation support the value of ED data for surveillance after natural disasters. Enhanced EMS data may be useful for monitoring a CO poisoning event, if these data are available to the health department promptly. ©2011 American Medical Association. All rights reserved.
McDonnell, R J; Wall, P G; Adak, G K; Evans, H S; Cowden, J M; Caul, E O
1995-09-15
Twenty-eight outbreaks of infectious intestinal disease, reported as being transmitted mainly by the person to person route, were identified in association with retail catering premises, such as hotels, restaurants, and public houses, in England and Wales between 1992 and 1994. Five thousand and forty-eight people were at risk in these outbreaks and 1234 were affected. Most of the outbreaks (over 90%) occurred in hotels. Small round structured viruses were the most commonly detected pathogens. Diarrhoea and vomiting were common symptoms and most of the outbreaks occurred in the summer months. Control measures to contain infectious individuals and improved hygiene measures are necessary to contain such outbreaks.
DeSilva, M B; Schafer, S; Kendall Scott, M; Robinson, B; Hills, A; Buser, G L; Salis, K; Gargano, J; Yoder, J; Hill, V; Xiao, L; Roellig, D; Hedberg, K
2016-01-01
Cryptosporidium, a parasite known to cause large drinking and recreational water outbreaks, is tolerant of chlorine concentrations used for drinking water treatment. Human laboratory-based surveillance for enteric pathogens detected a cryptosporidiosis outbreak in Baker City, Oregon during July 2013 associated with municipal drinking water. Objectives of the investigation were to confirm the outbreak source and assess outbreak extent. The watershed was inspected and city water was tested for contamination. To determine the community attack rate, a standardized questionnaire was administered to randomly sampled households. Weighted attack rates and confidence intervals (CIs) were calculated. Water samples tested positive for Cryptosporidium species; a Cryptosporidium parvum subtype common in cattle was detected in human stool specimens. Cattle were observed grazing along watershed borders; cattle faeces were observed within watershed barriers. The city water treatment facility chlorinated, but did not filter, water. The community attack rate was 28·3% (95% CI 22·1-33·6), sickening an estimated 2780 persons. Watershed contamination by cattle probably caused this outbreak; water treatments effective against Cryptosporidium were not in place. This outbreak highlights vulnerability of drinking water systems to pathogen contamination and underscores the need for communities to invest in system improvements to maintain multiple barriers to drinking water contamination.
Investigation of a type C/D botulism outbreak in free-range laying hens in France.
Souillard, R; Le Maréchal, C; Ballan, V; Rouxel, S; Léon, D; Balaine, L; Poëzevara, T; Houard, E; Robineau, B; Robinault, C; Chemaly, M; Le Bouquin, S
2017-04-01
In 2014, a botulism outbreak in a flock of laying hens was investigated in France. In the flock of 5020 hens, clinical signs of botulism occurred at 46 weeks of age. A type C/D botulism outbreak was confirmed using the mouse lethality assay for detection of botulinum toxin in serum and a real-time PCR test to detect Clostridium botulinum in intestinal contents. The disease lasted one week with a mortality rate of 2.6% without recurrence. Botulism in laying hens has rarely been reported. Five monthly visits were made to the farm between December 2014 and May 2015 for a longitudinal study of the persistence of C. botulinum in the poultry house after the outbreak, and to assess egg contamination by C. botulinum. Several samples were collected on each visit: in the house (from the ventilation circuit, the egg circuit, water and feed, droppings) and the surrounding area. Thirty clean and 30 dirty eggs were also swabbed at each visit. In addition, 12 dirty and 12 clean eggs were collected to analyse eggshell and egg content. The samples were analysed using real-time PCR to detect type C/D C. botulinum. The bacterium was still detected in the house more than 5 months after the outbreak, mostly on the walls and in the egg circuit. Regarding egg contamination, the bacteria were detected only on the shell but not in the content of the eggs. Control measures should therefore be implemented throughout the egg production period to avoid dissemination of the bacteria, particularly during egg collection.
Mazuet, Christelle; Ezan, Eric; Volland, Hervé; Becher, François
2012-01-01
In two outbreaks of food-borne botulism in France, Clostridium botulinum type A was isolated and characterized from incriminated foods. Botulinum neurotoxin type A was detected in the patients' sera by mouse bioassay and in vitro endopeptidase assay with an immunocapture step and identification of the cleavage products by mass spectrometry. PMID:22993181
Metagenomic Analysis of Viruses in Feces from Unsolved Outbreaks of Gastroenteritis in Humans
Moore, Nicole E.; Wang, Jing; Hewitt, Joanne; Croucher, Dawn; Williamson, Deborah A.; Paine, Shevaun; Yen, Seiha; Greening, Gail E.
2014-01-01
The etiology of an outbreak of gastroenteritis in humans cannot always be determined, and ∼25% of outbreaks remain unsolved in New Zealand. It is hypothesized that novel viruses may account for a proportion of unsolved cases, and new unbiased high-throughput sequencing methods hold promise for their detection. Analysis of the fecal metagenome can reveal the presence of viruses, bacteria, and parasites which may have evaded routine diagnostic testing. Thirty-one fecal samples from 26 gastroenteritis outbreaks of unknown etiology occurring in New Zealand between 2011 and 2012 were selected for de novo metagenomic analysis. A total data set of 193 million sequence reads of 150 bp in length was produced on an Illumina MiSeq. The metagenomic data set was searched for virus and parasite sequences, with no evidence of novel pathogens found. Eight viruses and one parasite were detected, each already known to be associated with gastroenteritis, including adenovirus, rotavirus, sapovirus, and Dientamoeba fragilis. In addition, we also describe the first detection of human parechovirus 3 (HPeV3) in Australasia. Metagenomics may thus provide a useful audit tool when applied retrospectively to determine where routine diagnostic processes may have failed to detect a pathogen. PMID:25339401
Waterborne disease outbreak detection: an integrated approach using health administrative databases.
Coly, S; Vincent, N; Vaissiere, E; Charras-Garrido, M; Gallay, A; Ducrot, C; Mouly, D
2017-08-01
Hundreds of waterborne disease outbreaks (WBDO) of acute gastroenteritis (AGI) due to contaminated tap water are reported in developed countries each year. Such outbreaks are probably under-detected. The aim of our study was to develop an integrated approach to detect and study clusters of AGI in geographical areas with homogeneous exposure to drinking water. Data for the number of AGI cases are available at the municipality level while exposure to tap water depends on drinking water networks (DWN). These two geographical units do not systematically overlap. This study proposed to develop an algorithm which would match the most relevant grouping of municipalities with a specific DWN, in order that tap water exposure can be taken into account when investigating future disease outbreaks. A space-time detection method was applied to the grouping of municipalities. Seven hundred and fourteen new geographical areas (groupings of municipalities) were obtained compared with the 1,310 municipalities and the 1,706 DWN. Eleven potential WBDO were identified in these groupings of municipalities. For ten of them, additional environmental investigations identified at least one event that could have caused microbiological contamination of DWN in the days previous to the occurrence of a reported WBDO.
Molecular Analysis of an Outbreak of Lethal Postpartum Sepsis Caused by Streptococcus pyogenes
Turner, Claire E.; Dryden, Matthew; Holden, Matthew T. G.; Davies, Frances J.; Lawrenson, Richard A.; Farzaneh, Leili; Bentley, Stephen D.; Efstratiou, Androulla
2013-01-01
Sepsis is now the leading direct cause of maternal death in the United Kingdom, and Streptococcus pyogenes is the leading pathogen. We combined conventional and genomic analyses to define the duration and scale of a lethal outbreak. Two postpartum deaths caused by S. pyogenes occurred within 24 h; one was characterized by bacteremia and shock and the other by hemorrhagic pneumonia. The women gave birth within minutes of each other in the same maternity unit 2 days earlier. Seven additional infections in health care and household contacts were subsequently detected and treated. All cluster-associated S. pyogenes isolates were genotype emm1 and were initially indistinguishable from other United Kingdom emm1 isolates. Sequencing of the virulence gene sic revealed that all outbreak isolates had the same unique sic type. Genome sequencing confirmed that the cluster was caused by a unique S. pyogenes clone. Transmission between patients occurred on a single day and was associated with casual contact only. A single isolate from one patient demonstrated a sequence change in sic consistent with longer infection duration. Transmission to health care workers was traced to single clinical contacts with index cases. The last case was detected 18 days after the first case. Following enhanced surveillance, the outbreak isolate was not detected again. Mutations in bacterial regulatory genes played no detectable role in this outbreak, illustrating the intrinsic ability of emm1 S. pyogenes to spread while retaining virulence. This fast-moving outbreak highlights the potential of S. pyogenes to cause a range of diseases in the puerperium with rapid transmission, underlining the importance of immediate recognition and response by clinical infection and occupational health teams. PMID:23616448
NASA Astrophysics Data System (ADS)
Merkord, C. L.; Liu, Y.; DeVos, M.; Wimberly, M. C.
2015-12-01
Malaria early detection and early warning systems are important tools for public health decision makers in regions where malaria transmission is seasonal and varies from year to year with fluctuations in rainfall and temperature. Here we present a new data-driven dynamic linear model based on the Kalman filter with time-varying coefficients that are used to identify malaria outbreaks as they occur (early detection) and predict the location and timing of future outbreaks (early warning). We fit linear models of malaria incidence with trend and Fourier form seasonal components using three years of weekly malaria case data from 30 districts in the Amhara Region of Ethiopia. We identified past outbreaks by comparing the modeled prediction envelopes with observed case data. Preliminary results demonstrated the potential for improved accuracy and timeliness over commonly-used methods in which thresholds are based on simpler summary statistics of historical data. Other benefits of the dynamic linear modeling approach include robustness to missing data and the ability to fit models with relatively few years of training data. To predict future outbreaks, we started with the early detection model for each district and added a regression component based on satellite-derived environmental predictor variables including precipitation data from the Tropical Rainfall Measuring Mission (TRMM) and land surface temperature (LST) and spectral indices from the Moderate Resolution Imaging Spectroradiometer (MODIS). We included lagged environmental predictors in the regression component of the model, with lags chosen based on cross-correlation of the one-step-ahead forecast errors from the first model. Our results suggest that predictions of future malaria outbreaks can be improved by incorporating lagged environmental predictors.
Thaiwong, T; Wise, A G; Maes, R K; Mullaney, T; Kiupel, M
2016-11-01
Recurrent outbreaks of sudden death and bloody diarrhea were reported in March 2013 and February 2014 in a breeding colony of Papillon dogs. During the first outbreak, 1 adult dog and 2 eight-month-old puppies died. During the second outbreak, 2 ten-week-old puppies died. One puppy from the first outbreak and 2 puppies from the second outbreak were examined at necropsy. Histologically, all 3 puppies had severe segmental crypt necrosis of the small intestine and marked lymphoid follicle depletion in the spleen and Peyer's patches. Real-time (RT) polymerase chain reaction (PCR) demonstrated abundant canine parvovirus (CPV-2) DNA (Ct<15) in the affected small intestine, and immunohistochemistry detected large amounts of CPV-2 antigen in intestinal crypt epithelium and Kupffer cells but few positive macrophages in lymphoid organs. All puppies had marked sinusoidal histiocytosis and multifocal granulomatous inflammation in mesenteric lymph nodes and spleen, prompting additional RT-PCR testing for canine circovirus 1 (CaCV-1). Very high levels of CaCV-1 DNA (Ct<13) were detected in small intestine, lymph nodes, and spleen. In situ hybridization for CaCV-1 detected rare positive nuclei of regenerating crypt epithelium but abundant amounts of CaCV-1 nucleic acid in the cytoplasm and nuclei of histiocytes in all lymphoid tissues, including granulomatous inflammatory foci and hepatic Kupffer cells. Significant levels of CaCV-1 DNA were detected in blood and serum (Ct as low as 13) but not feces from 3 surviving dogs at 2 months or 1 year after the outbreak, respectively. We hypothesize that CPV-2 infection predisposed dogs to CaCV-1 infection and ultimately resulted in more severe clinical disease. © The Author(s) 2016.
de Andrade, Juliana da Silva Ribeiro; Rocha, Monica Simões; Carvalho-Costa, Felipe Aníbal; Fioretti, Julia Monassa; Xavier, Maria da Penha Trindade Pinheiro; Nunes, Zenaida Maria Alves; Cardoso, Jeanice; Fialho, Alexandre Madi; Leite, José Paulo Gagliardi; Miagostovich, Marize Pereira
2014-11-01
Acute gastroenteritis norovirus (NoV) in a country of continental dimensions like Brazil has resulted in under-reporting of the number of outbreaks, as well as the genotypes associated. To demonstrate the role of NoV in outbreaks occurring in the State of Rio Grande do Sul, Southern Brazil, we determined its prevalence, as well as the genotypes associated, and evaluated clinical and epidemiological aspects. NoV investigation was carried out in rotavirus group A negative stool samples from 2265 patients from 741 outbreaks that occurred in the State of Rio Grande do Sul, Brazil, during a period of eight years (2004-2011). NoV detection and nucleotide sequencing for genotype characterization was carried by using sets of primers targeting a conservative Rd-Rp polymerase genome region and the viral capsid gene, respectively. NoVs were detected in 817 stool samples (36.1%) and associated with 327 outbreaks (44.1%). NoV GII.2, GII.3, GII.4, GII.6, GII.12, GII.13, GII.14, GII.15, GII.17, GII.21; and GI.1 and GI.3 were characterized. GII.4 was the most frequently detected (72.3%), with five variants identified (Asia_2003, Hunter_2004, Yerseke_2006a, Den_Haag_2006b, New Orleans_2009). This study describes the first detection of GI.1 and GII.13 and GII.15 in Brazil and demonstrates NoV winter-spring seasonality in this region of the country. NoVs were responsible for almost 50% of outbreaks, with about 70% of them resulting from genotype GII.4 and its variants. The seasonality observed could help health authorities to establish a system of active surveillance in order to reduce NoV impact especially in congregate settings. Copyright © 2014 Elsevier B.V. All rights reserved.
Wang, Ruiping; Jiang, Yonggen; Michael, Engelgau; Zhao, Genming
2017-06-12
China Centre for Diseases Control and Prevention (CDC) developed the China Infectious Disease Automated Alert and Response System (CIDARS) in 2005. The CIDARS was used to strengthen infectious disease surveillance and aid in the early warning of outbreak. The CIDARS has been integrated into the routine outbreak monitoring efforts of the CDC at all levels in China. Early warning threshold is crucial for outbreak detection in the CIDARS, but CDCs at all level are currently using thresholds recommended by the China CDC, and these recommended thresholds have recognized limitations. Our study therefore seeks to explore an operational method to select the proper early warning threshold according to the epidemic features of local infectious diseases. The data used in this study were extracted from the web-based Nationwide Notifiable Infectious Diseases Reporting Information System (NIDRIS), and data for infectious disease cases were organized by calendar week (1-52) and year (2009-2015) in Excel format; Px was calculated using a percentile-based moving window (moving window [5 week*5 year], x), where x represents one of 12 centiles (0.40, 0.45, 0.50….0.95). Outbreak signals for the 12 Px were calculated using the moving percentile method (MPM) based on data from the CIDARS. When the outbreak signals generated by the 'mean + 2SD' gold standard were in line with a Px generated outbreak signal for each week during the year of 2014, this Px was then defined as the proper threshold for the infectious disease. Finally, the performance of new selected thresholds for each infectious disease was evaluated by simulated outbreak signals based on 2015 data. Six infectious diseases were selected in this study (chickenpox, mumps, hand foot and mouth diseases (HFMD), scarlet fever, influenza and rubella). Proper thresholds for chickenpox (P75), mumps (P80), influenza (P75), rubella (P45), HFMD (P75), and scarlet fever (P80) were identified. The selected proper thresholds for these 6 infectious diseases could detect almost all simulated outbreaks within a shorter time period compared to thresholds recommended by the China CDC. It is beneficial to select the proper early warning threshold to detect infectious disease aberrations based on characteristics and epidemic features of local diseases in the CIDARS.
Feng, Shihui; Hossain, Liaquat; Crawford, John W; Bossomaier, Terry
2018-02-01
Social media provides us with a new platform on which to explore how the public responds to disasters and, of particular importance, how they respond to the emergence of infectious diseases such as Ebola. Provided it is appropriately informed, social media offers a potentially powerful means of supporting both early detection and effective containment of communicable diseases, which is essential for improving disaster medicine and public health preparedness. The 2014 West African Ebola outbreak is a particularly relevant contemporary case study on account of the large number of annual arrivals from Africa, including Chinese employees engaged in projects in Africa. Weibo (Weibo Corp, Beijing, China) is China's most popular social media platform, with more than 2 billion users and over 300 million daily posts, and offers great opportunity to monitor early detection and promotion of public health awareness. We present a proof-of-concept study of a subset of Weibo posts during the outbreak demonstrating potential and identifying priorities for improving the efficacy and accuracy of information dissemination. We quantify the evolution of the social network topology within Weibo relating to the efficacy of information sharing. We show how relatively few nodes in the network can have a dominant influence over both the quality and quantity of the information shared. These findings make an important contribution to disaster medicine and public health preparedness from theoretical and methodological perspectives for dealing with epidemics. (Disaster Med Public Health Preparedness. 2018;12:26-37).
Case study of the use of pulsed field gel electrophoresis in the detection of a food-borne outbreak.
De Lappe, Niall; Cormican, Martin
2015-01-01
In early July 2008, a cluster of six Salmonella Agona was identified in the Republic of Ireland. A dispersed, common source outbreak was suspected. Later in July a further case was identified and the Health Protection Agency in the UK indicated that they had 32 cases of S. Agona since Feb 2008. This chapter discusses how pulsed field gel electrophoresis was used to help confirm an outbreak and to trace the source of the outbreak.
Rift Valley Fever Outbreak in Livestock in Kenya, 2006–2007
Munyua, Peninah; Murithi, Rees M.; Wainwright, Sherrilyn; Githinji, Jane; Hightower, Allen; Mutonga, David; Macharia, Joseph; Ithondeka, Peter M.; Musaa, Joseph; Breiman, Robert F.; Bloland, Peter; Njenga, M. Kariuki
2010-01-01
We analyzed the extent of livestock involvement in the latest Rift Valley fever (RVF) outbreak in Kenya that started in December 2006 and continued until June 2007. When compared with previous RVF outbreaks in the country, the 2006–07 outbreak was the most extensive in cattle, sheep, goats, and camels affecting thousands of animals in 29 of 69 administrative districts across six of the eight provinces. This contrasted with the distribution of approximately 700 human RVF cases in the country, where over 85% of these cases were located in four districts; Garissa and Ijara districts in Northeastern Province, Baringo district in Rift Valley Province, and Kilifi district in Coast Province. Analysis of livestock and human data suggests that livestock infections occur before virus detection in humans, as supported by clustering of human RVF cases around livestock cases in Baringo district. The highest livestock morbidity and mortality rates were recorded in Garissa and Baringo districts, the same districts that recorded a high number of human cases. The districts that reported RVF in livestock for the first time in 2006/07 included Kitui, Tharaka, Meru South, Meru central, Mwingi, Embu, and Mbeere in Eastern Province, Malindi and Taita taveta in Coast Province, Kirinyaga and Murang'a in Central Province, and Baringo and Samburu in Rift Valley Province, indicating that the disease was occurring in new regions in the country. PMID:20682907
Scavia, Gaia; Alfonsi, Valeria; Taffon, Stefania; Escher, Martina; Bruni, Roberto; Medici, Dario De; Pasquale, Simona Di; Guizzardi, Sarah; Cappelletti, Benedetta; Iannazzo, Stefania; Losio, Nadia Marina; Pavoni, Enrico; Decastelli, Lucia; Ciccaglione, Anna Rita; Equestre, Michele; Tosti, Maria Elena; Rizzo, Caterina; National Italian Task Force On Hepatitis A
2017-03-01
In 2013/2014, Italy experienced one of the largest community-wide prolonged outbreaks of hepatitis A virus (HAV) throughout the country. The article provides a comprehensive description of the outbreak and the investigation carried out by a multidisciplinary National Task Force, in collaboration with regional and local public health authorities. Control strategies of food-borne HAV infection in both the human and food sectors are also described. Enhanced human epidemiological and microbiological surveillance together with microbiological monitoring of HAV in food and trace-back investigation were conducted. A total of 1803 HAV cases were identified from 1 January 2013 to 31 August 2014, in Italy. Sequencing was possible for 368 cases (20.4 %), mostly collected between 1 January 2013 and 28 February 2014, and 246 cases (66.8 %) harboured an HAV outbreak strain. Imported frozen berries contaminated with HAV were identified as the vehicle of the outbreak which also involved many other European countries in 2013 and 2014. Epidemiological evidence obtained through a case-control study was supported by the finding of a 100 % nucleotide similarity of the VP1/2A sequences of HAVs detected in human and food samples. Trace-back investigation revealed an extremely complex supplying network with no possibility for a point source potentially explaining the vast contamination of berries found in Italy. The investigation benefited from an excellent collaboration among different sectors who shared proactively the available information. Our findings highlight the importance of considering frozen berries among the highest risk factors for HAV.
Klinkenberg, D; Tobias, T J; Bouma, A; van Leengoed, L A M G; Stegeman, J A
2014-10-01
Actinobacillus pleuropneumoniae is a major cause of respiratory disease in pigs. Many farms are endemically infected without apparent disease, but occasionally severe outbreaks of pleuropneumonia occur. To prevent and control these outbreaks without antibiotics, the underlying mechanisms of these outbreaks need to be understood. Outbreaks are probably initiated by a trigger (common risk factor) changing the host-pathogen interaction, but it is unclear whether this trigger causes all cases directly (trigger mechanism), or whether the first case starts a transmission chain inducing disease in the infected contacts (transmission mechanism). The aim of this study was to identify conditions under which these mechanisms could cause A. pleuropneumoniae outbreaks, and to assess means for prevention and control. Outbreaks were first characterised by data from a literature review, defining an average outbreak at 12 weeks of age, affecting 50% of animals within 4 days. Simple mathematical models describing the two mechanisms can reproduce average outbreaks, with two observations supporting the trigger mechanism: (1) disease should be transmitted 50 times faster than supported by literature if there is a transmission chain; and (2) the trigger mechanism is consistent with the absence of reported outbreaks in young pigs as they have not yet been colonised by the bacterium. In conclusion, outbreaks of A. pleuropneumoniae on endemic farms are most likely caused by a trigger inducing pneumonia in already infected pigs, but more evidence is needed to identify optimum preventive interventions. Copyright © 2014 Elsevier Ltd. All rights reserved.
[Detection of local influenza outbreaks and role of virological diagnostics].
Schweiger, B; Buda, S
2013-01-01
For many years, the Working Group on Influenza (AGI) has been the most important influenza surveillance system in Germany. An average sample of the population is covered by both syndromic and virological surveillance, which provides timely data regarding the onset and course of the influenza wave as well as its burden of disease. However, smaller influenza outbreaks cannot be detected by the AGI sentinel system. This is achieved by the information reported by the mandatory notification system (Protection Against Infection Act, IfSG), which serves as the second pillar of the national influenza surveillance. Approaches to recognize such outbreaks are based either on reported influenza virus detection and subsequent investigations by local health authorities or by notification of an accumulation of respiratory diseases or nosocomial infections and subsequent laboratory investigations. In this context, virological diagnostics plays an essential role. This has been true particularly for the early phase of the 2009 pandemic, but generally timely diagnostics is essential for the identification of outbreaks. Regarding potential future outbreaks, it is also important to keep an eye on animal influenza viruses that have repeatedly infected humans. This mainly concerns avian influenza viruses of the subtypes H5, H7, and H9 as well as porcine influenza viruses for which a specific PCR has been established at the National Influenza Reference Centre. An increased incidence of respiratory infections, both during and outside the season, should always encourage virological laboratory diagnostics to be performed as a prerequisite of further extensive investigations and an optimal outbreak management.
Gerna, G; Forster, J; Parea, M; Sarasini, A; Di Matteo, A; Baldanti, F; Langosch, B; Schmidt, S; Battaglia, M
1990-07-01
A nosocomial outbreak of rotavirus gastroenteritis involving 52 newborns occurred between June and September 1988 at the University Children's Hospital of Freiburg, Federal Republic of Germany. Stools from 27 representative patients were examined for rotavirus serotypes, using a monoclonal antibody-based enzyme-linked immunosorbent assay. The electropherotype was also examined by polyacrylamide gel electrophoresis of genomic RNA. As many as 18 patients were found to be infected by serotype 4, subtype 4B strain, and in all of them the same electropherotype was detected. Although rotavirus from the remaining nine patients could not be typed, the electropherotype in four was identical to that of the serotype 4, subtype 4B strain. Thus, most of the patients in the outbreak were infected by the same rotavirus strain. Retrospective epidemiological studies showed that the 4B strain began to circulate at the hospital in January 1988, whereas only rotavirus serotypes 1, 3, and 4A were detected in 1985-1987. The primary case of the outbreak was presumably a newborn with acute gastroenteritis, admitted to the hospital from a small maternity unit in the same urban area. During the outbreak, 12 of 44 healthy newborns in the nurseries of the Children's Hospital and other maternity hospitals were found to be asymptomatic rotavirus carriers, and in three of the newborns the same 4B strain was detected. This is the first reported outbreak caused by a serotype 4, subtype 4B strain.
Crawshaw, W M; Caldow, G L
2015-04-25
This field study used data on the vaccine courses against bovine respiratory disease sold by one pharmaceutical company in conjunction with pharmacovigilance data to explore reported suspected lack of expected efficacy and the reasons for this. The study ran from May 1, 2007, to April 30, 2010, and covered vaccines sold in Scotland and part of Northumberland. In total, 83 groups of cattle reported suspected lack of expected efficacy, representing 1.6 per cent of the 804,618 vaccine courses sold. It was possible to investigate 45 of these outbreaks in depth using a standard questionnaire and diagnostic protocol. Vaccine usage outwith the specific product characteristics (SPC) occurred in 47 per cent of cases (21/45). The proportion of vaccination courses used where a pathogen contained in the vaccine was detected in the diseased cattle and vaccine use was consistent with the SPC was estimated at 0.12 per cent of the courses sold. Pasteurella multocida was the most common pathogen detected and was found in 21 of the outbreaks. For outbreaks where a pathogen contained in the vaccine was detected, P. multocida was found at a significantly greater frequency (P=0.03) where vaccine use was compliant with the SPC (five of six outbreaks) compared with outbreaks where vaccine use had not been compliant with the SPC (one of seven outbreaks). The limitations of the study, including the diagnostic tests employed and definition of vaccination outwith the SPC, are discussed. British Veterinary Association.
Yellow Fever Outbreak, Southern Sudan, 2003
Onyango, Clayton O.; Grobbelaar, Antoinette A.; Gibson, Georgina V.F.; Sang, Rosemary C.; Sow, Abdourahmane; Swanepoel, Robert
2004-01-01
In May 2003, an outbreak of fatal hemorrhagic fever, caused by yellow fever virus, occurred in southern Sudan. Phylogenetic analysis showed that the virus belonged to the East African genotype, which supports the contention that yellow fever is endemic in East Africa with the potential to cause large outbreaks in humans. PMID:15498174
Giménez Duran, Jaume; Galmés Truyols, Antònia; Nicolau Riutort, Antonio; Reina Prieto, Jorge; Gallegos Álvarez, Maria de Carmen; Pareja Bezares, Antonio; Vanrell Berga, Juana María
2010-01-01
The flu season 2009-2010 has been shorter and less severe than expected. Since January 2010, influenza surveillance systems indicated rates of very low incidence of influenza without detection of virus circulation. In this context, a hospital reported a suspected outbreak of severe respiratory disease, the aetiology proved influenza A(H1N1)v. We describe the outbreak and public health measures for their control. Descriptive study of an outbreak of pandemic influenza virus in a residency home for mentally disabled. Establishment of active surveillance. The case definition of influenza was very sensitive to detect new cases early, treated early and minimize transmission. Steps were taken to contain the influenza virus infection. Among 38 cases detected 7 had serious complications(all of them with risk factors). There were no deaths. The overall attack rate was 35.2%. The first cases were workers. The residents were ill at the peak of the outbreak, and among workers the presentation was more dispersed. None of the workers and only three of residents had been vaccinated. Workers possibly have initiated and contributed to the maintenance of transmission. We emphasize the need to comply with vaccination recommendations, not just those with risk factors, but particularly for workers in contact with those.
Thornley, C N; Harte, D J; Weir, R P; Allen, L J; Knightbridge, K J; Wood, P R T
2017-08-01
A legionellosis outbreak at an industrial site was investigated to identify and control the source. Cases were identified from disease notifications, workplace illness records, and from clinicians. Cases were interviewed for symptoms and risk factors and tested for legionellosis. Implicated environmental sources were sampled and tested for legionella. We identified six cases with Legionnaires' disease and seven with Pontiac fever; all had been exposed to aerosols from the cooling towers on the site. Nine cases had evidence of infection with either Legionella pneumophila serogroup (sg) 1 or Legionella longbeachae sg1; these organisms were also isolated from the cooling towers. There was 100% DNA sequence homology between cooling tower and clinical isolates of L. pneumophila sg1 using sequence-based typing analysis; no clinical L. longbeachae isolates were available to compare with environmental isolates. Routine monitoring of the towers prior to the outbreak failed to detect any legionella. Data from this outbreak indicate that L. pneumophila sg1 transmission occurred from the cooling towers; in addition, L. longbeachae transmission was suggested but remains unproven. L. longbeachae detection in cooling towers has not been previously reported in association with legionellosis outbreaks. Waterborne transmission should not be discounted in investigations for the source of L. longbeachae infection.
Optimizing the response to surveillance alerts in automated surveillance systems.
Izadi, Masoumeh; Buckeridge, David L
2011-02-28
Although much research effort has been directed toward refining algorithms for disease outbreak alerting, considerably less attention has been given to the response to alerts generated from statistical detection algorithms. Given the inherent inaccuracy in alerting, it is imperative to develop methods that help public health personnel identify optimal policies in response to alerts. This study evaluates the application of dynamic decision making models to the problem of responding to outbreak detection methods, using anthrax surveillance as an example. Adaptive optimization through approximate dynamic programming is used to generate a policy for decision making following outbreak detection. We investigate the degree to which the model can tolerate noise theoretically, in order to keep near optimal behavior. We also evaluate the policy from our model empirically and compare it with current approaches in routine public health practice for investigating alerts. Timeliness of outbreak confirmation and total costs associated with the decisions made are used as performance measures. Using our approach, on average, 80 per cent of outbreaks were confirmed prior to the fifth day of post-attack with considerably less cost compared to response strategies currently in use. Experimental results are also provided to illustrate the robustness of the adaptive optimization approach and to show the realization of the derived error bounds in practice. Copyright © 2011 John Wiley & Sons, Ltd.
Multiple exposures during a norovirus outbreak on a river-cruise sailing through Europe, 2006.
Verhoef, L; Boxman, I L; Duizer, E; Rutjes, S A; Vennema, H; Friesema, I H M; de Roda Husman, A M; Koopmans, M
2008-06-12
In the summer of 2006, several cruise-related viral gastroenteritis outbreaks were reported in Europe. One report came from a river-cruise, belonging to a ship-owner who had two other ships with outbreaks. This situation warranted onsite investigation in order to identify a potential common source of infection. A retrospective cohort study was performed among 137 people on board. Epidemiological questionnaire data were analysed using logistic regression. Stool, food, water and surface samples were collected for norovirus detection. Norovirus GGII.4-2006b was responsible for 48 gastroenteritis cases on this ship as confirmed in six patients. Identical norovirus sequences were detected in stool samples, on surfaces and in tap water. Epidemiological and microbiological data indicated multiple exposures contributing to the outbreak. Microbiological results demonstrated person-to-person transmission to be clearly present. Epidemiological results indicated that consuming tap water was a risk factor; however, this could not be concluded definitively on the basis of the available data. A common source for all cruise-related outbreaks was unlikely. The ongoing outbreaks on this ship demonstrated that evidence based guidelines on effective disinfection strategies are needed.
Hellmér, Maria; Paxéus, Nicklas; Magnius, Lars; Enache, Lucica; Arnholm, Birgitta; Johansson, Annette; Bergström, Tomas; Norder, Heléne
2014-11-01
Most persons infected with enterically transmitted viruses shed large amounts of virus in feces for days or weeks, both before and after onset of symptoms. Therefore, viruses causing gastroenteritis may be detected in wastewater, even if only a few persons are infected. In this study, the presence of eight pathogenic viruses (norovirus, astrovirus, rotavirus, adenovirus, Aichi virus, parechovirus, hepatitis A virus [HAV], and hepatitis E virus) was investigated in sewage to explore whether their identification could be used as an early warning of outbreaks. Samples of the untreated sewage were collected in proportion to flow at Ryaverket, Gothenburg, Sweden. Daily samples collected during every second week between January and May 2013 were pooled and analyzed for detection of viruses by concentration through adsorption to milk proteins and PCR. The largest amount of noroviruses was detected in sewage 2 to 3 weeks before most patients were diagnosed with this infection in Gothenburg. The other viruses were detected at lower levels. HAV was detected between weeks 5 and 13, and partial sequencing of the structural VP1protein identified three different strains. Two strains were involved in an ongoing outbreak in Scandinavia and were also identified in samples from patients with acute hepatitis A in Gothenburg during spring of 2013. The third strain was unique and was not detected in any patient sample. The method used may thus be a tool to detect incipient outbreaks of these viruses and provide early warning before the causative pathogens have been recognized in health care. Copyright © 2014, American Society for Microbiology. All Rights Reserved.
Hellmér, Maria; Paxéus, Nicklas; Magnius, Lars; Enache, Lucica; Arnholm, Birgitta; Johansson, Annette; Bergström, Tomas
2014-01-01
Most persons infected with enterically transmitted viruses shed large amounts of virus in feces for days or weeks, both before and after onset of symptoms. Therefore, viruses causing gastroenteritis may be detected in wastewater, even if only a few persons are infected. In this study, the presence of eight pathogenic viruses (norovirus, astrovirus, rotavirus, adenovirus, Aichi virus, parechovirus, hepatitis A virus [HAV], and hepatitis E virus) was investigated in sewage to explore whether their identification could be used as an early warning of outbreaks. Samples of the untreated sewage were collected in proportion to flow at Ryaverket, Gothenburg, Sweden. Daily samples collected during every second week between January and May 2013 were pooled and analyzed for detection of viruses by concentration through adsorption to milk proteins and PCR. The largest amount of noroviruses was detected in sewage 2 to 3 weeks before most patients were diagnosed with this infection in Gothenburg. The other viruses were detected at lower levels. HAV was detected between weeks 5 and 13, and partial sequencing of the structural VP1protein identified three different strains. Two strains were involved in an ongoing outbreak in Scandinavia and were also identified in samples from patients with acute hepatitis A in Gothenburg during spring of 2013. The third strain was unique and was not detected in any patient sample. The method used may thus be a tool to detect incipient outbreaks of these viruses and provide early warning before the causative pathogens have been recognized in health care. PMID:25172863
Durr, Peter A; Graham, Kerryne; van Klinken, Rieks D
2017-01-01
The possibility that outbreaks of bluetongue (BT) and African horse sickness (AHS) might occur via long-distance wind dispersion (LDWD) of their insect vector ( Culicoides spp.) was proposed by R. F. Sellers in a series of papers published between 1977 and 1991. These investigated the role of LDWD by means of visual examination of the wind direction of synoptic weather charts. Based on the hypothesis that simple wind direction analysis, which does not allow for wind speed, might have led to spurious conclusions, we reanalyzed six of the outbreak scenarios described in Sellers' papers. For this reanalysis, we used a custom-built Big Data application (" TAPPAS ") which couples a user-friendly web-interface with an established atmospheric dispersal model (" HYSPLIT "), thus enabling more sophisticated modeling than was possible when Sellers undertook his analyzes. For the two AHS outbreaks, there was strong support from our reanalysis of the role of LDWD for that in Spain (1966), and to a lesser degree, for the outbreak in Cyprus (1960). However, for the BT outbreaks, the reassessments were more complex, and for one of these (western Turkey, 1977) we could discount LDWD as the means of direct introduction of the virus. By contrast, while the outbreak in Cyprus (1977) showed LDWD was a possible means of introduction, there is an apparent inconsistency in that the outbreaks were localized while the dispersion events covered much of the island. For Portugal (1956), LDWD from Morocco on the dates suggested by Sellers is very unlikely to have been the pathway for introduction, and for the detection of serotype 2 in Florida (1982), LDWD from Cuba would require an assumption of a lengthy survival time of the midges in the air column. Except for western Turkey, the BT reanalyses show the limitation of LDWD modeling when used by itself, and indicates the need to integrate susceptible host population distribution (and other covariate) data into the modeling process. A further refinement, which will become increasingly important to assess LDWD, will be the use of virus and vector genome sequence data collected from potential source and the incursion sites.
Alvarez, Josep; Domínguez, Angela; Sabrià, Miquel; Ruiz, Laura; Torner, Nuria; Cayla, Joan; Barrabeig, Irene; Sala, M Rosa; Godoy, Pere; Camps, Neus; Minguell, Sofia
2009-11-01
To describe the characteristics of community outbreaks of legionellosis in Catalonia, Spain from 1990 to 2004, to compare two time periods (1990-1996 and 1997-2004), and to assess the influence of outbreak characteristics on the case fatality rate (CFR). This is a descriptive analysis of the outbreaks detected by epidemiological surveillance units in Catalonia. Variables potentially related to the CFR were analyzed by logistic regression. Of the 118 outbreaks involving 690 patients (overall CFR 4.5%), the urinary antigen test (UAT) was used for first case diagnosis in 80.5%. The origin of the outbreak was identified as a cooling tower in 35.6%, as a water distribution system in a public building in 14.4%, and a water distribution system at other sites in 7.6%. Statistically significant differences were found in the CFR (12.2% vs. 3.9%; p=0.018) and detection of the first case by UAT (0.0% vs. 87.2%; p<0.001) between the two time periods investigated. Logistic regression showed an increase in the CFR according to outbreak size (adjusted odds ratio (aOR) 1.18; 95% confidence interval (CI) 1.05-1.33) that was significantly lower in the second period (aOR 0.09; 95% CI 0.04-0.20). Since the UAT was introduced, early diagnosis and treatment has helped to improve the outcomes and CFR of cases involved in outbreaks of legionellosis.
Cartelle Gestal, Monica; Zurita, Jeannete; Gualpa, Gabriela; Gonzalez, Cecibel; Paz Y Mino, Ariane
2016-12-30
Acinetobacter baumannii (ABA) is an important opportunistic pathogen associated with high mortality rates in intensive care units (ICUs). An outbreak in the ICU of a secondary-level hospital in Quito, Ecuador, occurred during April and May 2015 and was successfully controlled. Enterobacterial repetitive intergenic consensus polymerase chain reaction (ERIC-PCR) and repetitive element palindromic (REP)-PCR was conducted on all isolates recovered from patients, as well as environmental samples, to confirm the presence of an outbreak. A case-control study was conducted by comparing the clinical histories of the affected patients and of control patients present in the ICU during the outbreak period who did not present a positive culture for ABA. Five patients were infected and two were colonized with the same clonal strain of ABA, which was also identified on the stethoscope and a monitor associated with an isolation room. Statistical analysis of case histories did not identify any additional risk factors, but the outbreak was initiated by one patient in the isolation room of the ICU who was infected with the outbreak strain. All patients who ocupied that room after the index case tested positive for at least one culture of ABA. The outbreak strain was found on the stethoscope, and a subclone was found on the monitor of that room. Having access to basic equipment will enable well-trained professionals to rapidly detect and initiate the control process of an outbreak, saving lives and money spent on nosocomial infection treatments.
Yellow Fever Virus in Haemagogus leucocelaenus and Aedes serratus Mosquitoes, Southern Brazil, 2008
Cardoso, Jáder da C.; de Almeida, Marco A.B.; dos Santos, Edmilson; da Fonseca, Daltro F.; Sallum, Maria A.M.; Noll, Carlos A.; Monteiro, Hamilton A. de O.; Cruz, Ana C.R.; Carvalho, Valéria L.; Pinto, Eliana V.; Castro, Francisco C.; Neto, Joaquim P. Nunes; Segura, Maria N.O.
2010-01-01
Yellow fever virus (YFV) was isolated from Haemagogus leucocelaenus mosquitoes during an epizootic in 2001 in the Rio Grande do Sul State in southern Brazil. In October 2008, a yellow fever outbreak was reported there, with nonhuman primate deaths and human cases. This latter outbreak led to intensification of surveillance measures for early detection of YFV and support for vaccination programs. We report entomologic surveillance in 2 municipalities that recorded nonhuman primate deaths. Mosquitoes were collected at ground level, identified, and processed for virus isolation and molecular analyses. Eight YFV strains were isolated (7 from pools of Hg. leucocelaenus mosquitoes and another from Aedes serratus mosquitoes); 6 were sequenced, and they grouped in the YFV South American genotype I. The results confirmed the role of Hg. leucocelaenus mosquitoes as the main YFV vector in southern Brazil and suggest that Ae. serratus mosquitoes may have a potential role as a secondary vector. PMID:21122222
Hantavirus Pulmonary Syndrome in the United States.
Fabbri, Marilyn; Maslow, Melanie J.
2001-06-01
Since the first outbreak of hantavirus pulmonary syndrome (HPS) in 1993, understanding of the vast distribution and potential impact of hantaviruses has grown. At least 277 cases of HPS have been documented in the United States. The full clinical spectrum has yet to be elucidated, and one outbreak suggested the possibility of person-to-person transmission. New research has identified the b-3 integrins as cellular receptors for hantaviruses and has determined the pivotal role of the immune system in pathogenesis. Rapid diagnosis has been facilitated by a new immunoblot assay to detect Sin Nombre virus infection. Treatment remains primarily supportive; however, a placebo- controlled trial of ribavirin is ongoing. Extracorporeal membrane oxygenation may be a potential therapy in severe cases; inhaled nitric oxide needs further study. Vaccines developed against hantaviruses associated with hemorrhagic fever and renal syndrome might be effective against HPS-associated strains.
Tappero, Jordan W; Cassell, Cynthia H; Bunnell, Rebecca E; Angulo, Frederick J; Craig, Allen; Pesik, Nicki; Dahl, Benjamin A; Ijaz, Kashef; Jafari, Hamid; Martin, Rebecca
2017-12-01
To achieve compliance with the revised World Health Organization International Health Regulations (IHR 2005), countries must be able to rapidly prevent, detect, and respond to public health threats. Most nations, however, remain unprepared to manage and control complex health emergencies, whether due to natural disasters, emerging infectious disease outbreaks, or the inadvertent or intentional release of highly pathogenic organisms. The US Centers for Disease Control and Prevention (CDC) works with countries and partners to build and strengthen global health security preparedness so they can quickly respond to public health crises. This report highlights selected CDC global health protection platform accomplishments that help mitigate global health threats and build core, cross-cutting capacity to identify and contain disease outbreaks at their source. CDC contributions support country efforts to achieve IHR 2005 compliance, contribute to the international framework for countering infectious disease crises, and enhance health security for Americans and populations around the world.
Yellow fever virus in Haemagogus leucocelaenus and Aedes serratus mosquitoes, southern Brazil, 2008.
Cardoso, Jader da C; de Almeida, Marco A B; dos Santos, Edmilson; da Fonseca, Daltro F; Sallum, Maria A M; Noll, Carlos A; Monteiro, Hamilton A de O; Cruz, Ana C R; Carvalho, Valeria L; Pinto, Eliana V; Castro, Francisco C; Nunes Neto, Joaquim P; Segura, Maria N O; Vasconcelos, Pedro F C
2010-12-01
Yellow fever virus (YFV) was isolated from Haemagogus leucocelaenus mosquitoes during an epizootic in 2001 in the Rio Grande do Sul State in southern Brazil. In October 2008, a yellow fever outbreak was reported there, with nonhuman primate deaths and human cases. This latter outbreak led to intensification of surveillance measures for early detection of YFV and support for vaccination programs. We report entomologic surveillance in 2 municipalities that recorded nonhuman primate deaths. Mosquitoes were collected at ground level, identified, and processed for virus isolation and molecular analyses. Eight YFV strains were isolated (7 from pools of Hg. leucocelaenus mosquitoes and another from Aedes serratus mosquitoes); 6 were sequenced, and they grouped in the YFV South American genotype I. The results confirmed the role of Hg. leucocelaenus mosquitoes as the main YFV vector in southern Brazil and suggest that Ae. serratus mosquitoes may have a potential role as a secondary vector.
Ehizibolo, D O; Haegeman, A; De Vleeschauwer, A R; Umoh, J U; Kazeem, H M; Okolocha, E C; Van Borm, S; De Clercq, K
2017-12-01
Control measures for foot and mouth disease (FMD) in Nigeria have not been implemented due to the absence of locally produced vaccines and risk-based analysis resulting from insufficient data on the circulating FMD virus (FMDV) serotypes/strains. In 2013-2015, blood and epithelial samples were collected from reported FMD outbreaks in four states (Kaduna, Kwara, Plateau and Bauchi) in northern Nigeria. FMDV non-structural protein (NSP) seroprevalence for the outbreaks was estimated at 80% (72 of 90) and 70% (131 of 188) post-outbreak. Antibodies against FMDV serotypes O, A, SAT1, SAT2 and SAT3 were detected across the states using solid-phase competitive ELISA. FMDV genome was detected in 99% (73 of 74) of the samples from FMD-affected animals using rRT-PCR, and cytopathic effect was found in cell culture by 59% (44 of 74) of these samples. Three FMDV serotypes O, A and SAT2 were isolated and characterized. The phylogenetic assessments of the virus isolates showed that two topotypes of FMDV serotype O, East Africa-3 (EA-3) and West Africa (WA) topotypes were circulating, as well as FMDV strains belonging to the Africa genotype (G-IV) of serotype A and FMDV SAT2 topotype VII strains. While the serotype O (EA-3) strains from Nigeria were most closely related to a 1999 virus strain from Sudan, the WA strain in Nigeria shares genetic relationship with three 1988 viruses in Niger. The FMDV serotype A strains were closely related to a known virus from Cameroon, and the SAT2 strains were most closely related to virus subtypes in Libya. This study provides evidence of co-occurrence of FMDV serotypes and topotypes in West, Central, East and North Africa, and this has implication for control. The findings help filling the knowledge gap of FMDV dynamics in Nigeria and West Africa subregion to support local and regional development of vaccination-based control plans and international risk assessment. © 2017 Blackwell Verlag GmbH.
[Epidemiological characteristics of influenza outbreaks in China, 2005-2013].
Li, Ming; Feng, Luzhao; Cao, Yu; Peng, Zhibin; Yu, Hongjie
2015-07-01
To understand the epidemiological characteristics of influenza outbreaks in China from 2005 to 2013. The data of influenza-like illness outbreaks involving 10 or more cases were collected through Public Health Emergency Management Information System and National Influenza Surveillance Information System in China, and the influenza outbreaks were identified according to the laboratory detection results. Descriptive epidemiological analysis was conducted to understand the type/subtype of influenza virus and outbreak time, area, place and extent. From 2005 to 2013, a total of 3 252 influenza-like illness outbreaks were reported in the mainland of China, in which 2 915 influenza outbreaks were laboratory confirmed, and influenza A (H1N1) pdm09 virus and influenza B virus were predominant. More influenza outbreaks were reported in the influenza A (H1N1) pandemic during 2009-2010. Influenza outbreaks mainly occurred during winter-spring, and less influenza outbreaks occurred in winter and summer vacations of schools. More influenza outbreaks were reported in southern provinces, accounting for 79% of the total. Influenza outbreaks mainly occurred in primary and middle schools, where 2 763 outbreaks were reported, accounting for 85% of the total. Average 30-99 people were involved in an outbreak. A large number of influenza outbreaks occur during influenza season every year in China, the predominant virus type or subtype varies with season. Primary and middle schools are mainly affected by influenza outbreaks.
A Growing Global Network’s Role in Outbreak Response: AFHSC-GEIS 2008-2009
2011-01-01
network and included a wide spectrum of support activities in collaboration with host country partners, several of which were in direct support of the... activities in collaboration with host country partners, several of which were in direct support of the World Health Organization?s (WHO) International...military’s role in supporting outbreak response activities within their own countries [6]. In late 2006, Chretien et al., provided a detailed break- down of
A spatial model of socioeconomic and environmental determinants of dengue fever in Cali, Colombia.
Delmelle, Eric; Hagenlocher, Michael; Kienberger, Stefan; Casas, Irene
2016-12-01
Dengue fever has gradually re-emerged across the global South, particularly affecting urban areas of the tropics and sub-tropics. The dynamics of dengue fever transmission are sensitive to changes in environmental conditions, as well as local demographic and socioeconomic factors. In 2010, the municipality of Cali, Colombia, experienced one of its worst outbreaks, however the outbreak was not spatially homogeneous across the city. In this paper, we evaluate the role of socioeconomic and environmental factors associated with this outbreak at the neighborhood level, using a Geographically Weighted Regression model. Key socioeconomic factors include population density and socioeconomic stratum, whereas environmental factors are proximity to both tire shops and plant nurseries and the presence of a sewage system (R 2 =0.64). The strength of the association between these factors and the incidence of dengue fever is spatially heterogeneous at the neighborhood level. The findings provide evidence to support public health strategies in allocating resources locally, which will enable a better detection of high risk areas, a reduction of the risk of infection and to strengthen the resilience of the population. Published by Elsevier B.V.
Vicente, Ana C P; Teixeira, Luiz F M; Iniguez-Rojas, L; Luna, M G; Silva, L; Andrade, J R C; Guth, B E C
2005-09-01
The relationship between enteropathogens and severe diarrhoea in the Brazilian Amazon is poorly understood. In 1998, outbreaks of acute diarrhoea clinically diagnosed as cholera occurred in two small villages localized far from the main cholera route in the Brazilian rainforest. PCR was performed on some enteropathogens and heat-labile (LT) and/or heat-stable (STh) toxin genes, the virulence determinants of enterotoxigenic Escherichia coli (ETEC), were detected. Further characterization of ETEC isolates revealed the presence of two clones, one from each outbreak. One presenting serotype O167:H5 harboured LT-I and STh toxin genes and expressed the CS5CS6 colonization factor. The other, a non-typeable serotype, was positive for the LT-I gene and expressed the CS7 colonization factor. The current study demonstrates the importance of molecular diagnosis in regions such as the Amazon basin, where the enormous distances and local support conditions make standard laboratory diagnosis difficult. Here we also show that the mis-identified cholera cases were in fact associated with ETEC strains. This is the first report of ETEC, molecularly characterized as the aetiological agent of severe diarrhoea in children and adults in the Brazilian Amazon Rainforest.
Outbreak of Salmonella Typhimurium 44 related to egg consumption.
Dyda, Amalie; Hundy, Rebecca; Moffatt, Cameron R M; Cameron, Scott
2009-12-01
ACT Health investigated an outbreak of gastroenteritis associated with a local restaurant in December 2008. The infecting agent was Salmonella serotype Typhimurium phage type 44. A case control study was conducted to identify the source of infection. A total of 22 cases and 9 controls were recruited to take part in the study. Both poached eggs (odds ratio [OR] 42.00) and hollandaise sauce (OR 19.00) had elevated odds ratios that were statistically significant. The major limitation of the study was the small sample size and small number of controls. Despite this, a strong association with illness and consumption of eggs and hollandaise sauce was detected and this was further supported by environmental evidence. The investigation concluded that the cause of the outbreak was putatively contaminated eggs, either on their own or as an ingredient used in hollandaise sauce. The investigation and control measures led to an improvement in hygiene practices at the restaurant and contributed to the voluntary recall of the contaminated batch of eggs from the Australian Capital Territory. The results of the study also build upon other evidence that egg-related salmonellosis is now common in Australia and attention to commercial practices at production and processing is overdue.
Support vector machine applied to predict the zoonotic potential of E. coli O157 cattle isolates
USDA-ARS?s Scientific Manuscript database
Methods based on sequence data analysis facilitate the tracking of disease outbreaks, allow relationships between strains to be reconstructed and virulence factors to be identified. However, these methods are used postfactum after an outbreak has happened. Here, we show that support vector machine a...
Interagency Coordination in the Case of an Intentional Agroterrorist Incident
2009-05-11
and working groups; development of a National Veterinary Stockpile of vaccines needed to respond to animal diseases; and funding of research...outbreak or an intentional incident. They include lack of personnel able to recognize a foreign animal disease outbreak, difficulty with vaccination and... vaccination stockpiling, and difficulty detecting a covert attack and differentiating it from a natural outbreak with the current surveillance and
Gastroenteritis outbreak caused by waterborne norovirus at a New Zealand ski resort.
Hewitt, Joanne; Bell, Derek; Simmons, Greg C; Rivera-Aban, Malet; Wolf, Sandro; Greening, Gail E
2007-12-01
In July 2006, public health services investigated an outbreak of acute gastroenteritis among staff and visitors of a popular ski resort in southern New Zealand. The source of the outbreak was a drinking water supply contaminated by human sewage. The virological component of the investigation played a major role in confirming the source of the outbreak. Drinking water, source stream water, and 31 fecal specimens from gastroenteritis outbreak cases were analyzed for the presence of norovirus (NoV). Water samples were concentrated by ultrafiltration, and real-time reverse transcription-PCR (RT-PCR) was used for rapid detection of NoV from both water and fecal samples. The implicated NoV strain was further characterized by DNA sequencing. NoV genogroup GI/5 was identified in water samples and linked case fecal specimens, providing clear evidence of the predominant pathogen and route of exposure. A retrospective cohort study demonstrated that staff who consumed drinking water from the resort supply were twice as likely to have gastroenteritis than those who did not. This is the first time that an outbreak of gastroenteritis in New Zealand has been conclusively linked to NoV detected in a community water supply. To our knowledge, this is the first report of the use of ultrafiltration combined with quantitative real-time RT-PCR and DNA sequencing for investigation of a waterborne NoV outbreak.
Molecular characterization of Hepatitis A virus causing an outbreak among Thai navy recruits.
Theamboonlers, A; Rianthavorn, P; Jiamsiri, S; Kumthong, S; Silaporn, P; Thongmee, C; Poovorawan, Y
2009-12-01
Hepatitis A virus (HAV) infection is a communicable disease, typically transmitted by faecal-oral contamination. HAV outbreaks usually occur in endemic areas. We report an outbreak of HAV from June to July, 2008 among Thai navy recruits who had received training at the Sattahip Navy Base, Chonburi province, Thailand. Upon conclusion of the training, the recruits were deployed to serve at several navy bases across the country. Secondary cases of HAV infection were reported among military personnel from these navy bases. To elucidate origin and distribution of these outbreaks, we characterized the genome and genotype of HAV isolated from the different navy bases. Sera and stool from the subjects were tested for antiHAV IgM, antiHAV IgG and HAV RNA. Subsequently, molecular characterization of HAV was performed by nucleotide sequencing of the VP1-P2A region, BLAST/FASTA and phylogenetic analysis. HAV RNA was detected in specimens obtained from different areas. All isolated strains clustered in the same lineage and belonged to genotype 1A. They shared nearly 100% genome homology indicating a single point source of this outbreak. This study provides essential baseline data as a reference for genetic analysis of HAV strains causing future outbreaks. Early detection of HAV infection and identification of the source by using molecular characterization and prompt preventive measures will hopefully prevent further outbreaks.
The Methanol Poisoning Outbreaks in Libya 2013 and Kenya 2014.
Rostrup, Morten; Edwards, Jeffrey K; Abukalish, Mohamed; Ezzabi, Masoud; Some, David; Ritter, Helga; Menge, Tom; Abdelrahman, Ahmed; Rootwelt, Rebecca; Janssens, Bart; Lind, Kyrre; Paasma, Raido; Hovda, Knut Erik
2016-01-01
Outbreaks of methanol poisoning occur frequently on a global basis, affecting poor and vulnerable populations. Knowledge regarding methanol is limited, likely many cases and even outbreaks go unnoticed, with patients dying unnecessarily. We describe findings from the first three large outbreaks of methanol poisoning where Médecins Sans Frontières (MSF) responded, and evaluate the benefits of a possible future collaboration between local health authorities, a Non-Governmental Organisation and international expertise. Retrospective study of three major methanol outbreaks in Libya (2013) and Kenya (May and July 2014). Data were collected from MSF field personnel, local health personnel, hospital files, and media reports. In Tripoli, Libya, over 1,000 patients were poisoned with a reported case fatality rate of 10% (101/1,066). In Kenya, two outbreaks resulted in approximately 341 and 126 patients, with case fatality rates of 29% (100/341) and 21% (26/126), respectively. MSF launched an emergency team with international experts, medications and equipment, however, the outbreaks were resolving by the time of arrival. Recognition of an outbreak of methanol poisoning and diagnosis seem to be the most challenging tasks, with significant delay from time of first presentations to public health warnings being issued. In spite of the rapid response from an emergency team, the outbreaks were nearly concluded by the time of arrival. A major impact on the outcome was not seen, but large educational trainings were conducted to increase awareness and knowledge about methanol poisoning. Based on this training, MSF was able to send a local emergency team during the second outbreak, supporting that such an approach could improve outcomes. Basic training, simplified treatment protocols, point-of-care diagnostic tools, and early support when needed, are likely the most important components to impact the consequences of methanol poisoning outbreaks in these challenging contexts.
Liao, Qiao; Shan, Zhengang; Wang, Min; Huang, Jieting; Xu, Ru; Huang, Ke; Tang, Xi; Zhang, Weiyun; Nelson, Kenrad; Li, Chengyao; Fu, Yongshui; Rong, Xia
2017-11-01
In 2014, an outbreak of dengue virus (DENV) infection led to 45 171 clinical cases diagnosed in Guangdong province, Southern China. However, the potential risk of blood donors asymptomatically infected with DENV has not been evaluated . In the current study we detected anti-DENV IgG antibody and RNA in volunteer Chinese blood donors. We found that anti-DENV IgG antibody was positively detected in 3.4% (51/1500) and two donors were detected as being DENV RNA positive out of 3000 blood samples. We concluded that the presence of potential DENV in blood donors might be potential risk for blood safety. Therefore, screening for DENV infection should be considered in blood donations during a period of dengue outbreak in high epidemic area of China. © 2017 Wiley Periodicals, Inc.
Detection of human norovirus from frozen raspberries in a cluster of gastroenteritis outbreaks.
Maunula, L; Roivainen, M; Keränen, M; Mäkela, S; Söderberg, K; Summa, M; von Bonsdorff, C H; Lappalainen, M; Korhonen, T; Kuusi, M; Niskanen, T
2009-12-10
We describe a cluster of norovirus outbreaks affecting about 200 people in Southern Finland in September and October 2009. All outbreaks occurred after consumption of imported raspberries from the same batch intended for the catering sector. Human norovirus genotype GI.4 was found in frozen raspberries. The berries were served in toppings of cakes in separate catering settings or mixed in curd cheese as a snack for children in a daycare center. The relative risk for consumption of the berry dish was 3.0 (p
Neira, Victor; Rabinowitz, Peter; Rendahl, Aaron; Paccha, Blanca; Gibbs, Shawn G; Torremorell, Montserrat
2016-01-01
Indirect transmission of influenza A virus (IAV) in swine is poorly understood and information is lacking on levels of environmental exposure encountered by swine and people during outbreaks of IAV in swine barns. We characterized viral load, viability and persistence of IAV in air and on surfaces during outbreaks in swine barns. IAV was detected in pigs, air and surfaces from five confirmed outbreaks with 48% (47/98) of oral fluid, 38% (32/84) of pen railing and 43% (35/82) of indoor air samples testing positive by IAV RT-PCR. IAV was isolated from air and oral fluids yielding a mixture of subtypes (H1N1, H1N2 and H3N2). Detection of IAV RNA from air was sustained during the outbreaks with maximum levels estimated between 7 and 11 days from reported onset. Our results indicate that during outbreaks of IAV in swine, aerosols and surfaces in barns contain significant levels of IAV potentially representing an exposure hazard to both swine and people.
Imported dengue from 2013 Angola outbreak: Not just serotype 1 was detected.
Abreu, Cândida; Silva-Pinto, André; Lazzara, Daniela; Sobrinho-Simões, Joana; Guimarães, João Tiago; Sarmento, António
2016-06-01
All the reports from Angola's 2013 dengue outbreak revealed serotype 1. However, previously dengue serotypes 1-4 have been reported in Africa and in 2014 serotype 4 was reported in Angola. To report dengue serotypes in patients returning from Angola during 2013 outbreak. Retrospective, cross-sectional study. We serotyped the dengue by an in house Polymerase Chain Reaction technique in randomly selected cases. From the 2013 Angola's dengue outbreak we treated 47 adult patients. None had history of past dengue. A combo kit test for dengue revealed positive NS1 antigen in 39 and IgM antibodies in 8. From 17 randomly patients tested by RNA Real Time-PCR, 11 were positive: 7 for DENV-1, 2 for DENV-2, 1 for DENV-3 (co-infected with DENV-1) and 1 for DENV-4. None had a complicated or fatal evolution. Unlike previous reports the 4 serotypes were detected, and this resulted in a different epidemiological situation, raising the risk of future outbreaks of severe dengue. Copyright © 2016 Elsevier B.V. All rights reserved.
Echovirus 30 meningitis epidemic followed by an outbreak-specific RT-qPCR.
Österback, Riikka; Kalliokoski, Teemu; Lähdesmäki, Tuire; Peltola, Ville; Ruuskanen, Olli; Waris, Matti
2015-08-01
An outbreak of enteroviral aseptic meningitis emerged in Southwestern Finland in August 2009. The same enterovirus reappeared with increasing incidence of meningitis in other parts of Finland in 2010. To identify the incidence and molecular epidemiology of enteroviral meningitis outbreak. The causative agent was identified as echovirus 30 (E-30) by sequencing partial viral protein 1 capsid genome, and a virus type-specific RT-qPCR was set up for sensitive detection of the virus in cerebrospinal fluid specimens. Enterovirus positive CSF specimens were subjected to the E-30-specific assay to investigate this unusual occurrence of aseptic meningitis and facilitate case confirmation during the outbreaks between August 2009 and September 2010. E-30 was detected in 106 (72%) enterovirus positive cerebrospinal fluid specimens. All the meningitis cases in 2009 and most of them in 2010 were among adolescents and several were members of sport teams. Between August 2009 and September 2010, E-30 caused an extensive outbreak with two peaks in Finland. Type-specific RT-PCR allowed rapid diagnostic follow-up of the epidemic. Copyright © 2015 Elsevier B.V. All rights reserved.
Vasant, Bhakti R; Stafford, Russell J; Jennison, Amy V; Bennett, Sonya M; Bell, Robert J; Doyle, Christine J; Young, Jeannette R; Vlack, Susan A; Titmus, Paul; El Saadi, Debra; Jarvinen, Kari A J; Coward, Patricia; Barrett, Janine; Staples, Megan; Graham, Rikki M A; Smith, Helen V; Lambert, Stephen B
2017-10-01
During a large outbreak of Shiga toxin-producing Escherichia coli illness associated with an agricultural show in Australia, we used whole-genome sequencing to detect an IS1203v insertion in the Shiga toxin 2c subunit A gene of Shiga toxin-producing E. coli. Our study showed that clinical illness was mild, and hemolytic uremic syndrome was not detected.
Tomas Vaclavik; Alan Kanaskie; Everett M. Hansen; Janet L. Ohmann; Ross K. Meentemeyer
2010-01-01
An isolated outbreak of the emerging forest disease sudden oak death was discovered in Oregon forests in 2001. Despite considerable control efforts, disease continues to spread from the introduction site due to slow and incomplete detection and eradication. Annual field surveys and laboratory tests between 2001 and 2009 confirmed a total of 802 infested locations. Here...
Yaari, Rami; Kaliner, Ehud; Grotto, Itamar; Katriel, Guy; Moran-Gilad, Jacob; Sofer, Danit; Mendelson, Ella; Miller, Elizabeth; Huppert, Amit; Anis, E; Kopel, E; Manor, Y; Mor, O; Shulman, L; Singer, R; Weil, M
2016-06-23
Polio eradication is an extraordinary globally coordinated health program in terms of its magnitude and reach, leading to the elimination of wild poliovirus (WPV) in most parts of the world. In 2013, a silent outbreak of WPV was detected in Israel, a country using an inactivated polio vaccine (IPV) exclusively since 2005. The outbreak was detected using environmental surveillance (ES) of sewage reservoirs. Stool surveys indicated the outbreak to be restricted mainly to children under the age of 10 in the Bedouin population of southern Israel. In order to curtail the outbreak, a nationwide vaccination campaign using oral polio vaccine (OPV) was conducted, targeting all children under 10. A transmission model, fitted to the results of the stool surveys, with additional conditions set by the ES measurements, was used to evaluate the prevalence of WPV in Bedouin children and the effectiveness of the vaccination campaign. Employing the parameter estimates of the model fitting, the model was used to investigate the effect of alternative timings, coverages and dosages of the OPV campaign on the outcome of the outbreak. The mean estimate for the mean reproductive number was 1.77 (95 % credible interval, 1.46-2.30). With seasonal variation, the reproductive number maximum range was between zero and six. The mean estimate for the mean infectious periods was 16.8 (8.6-24.9) days. The modeling indicates the OPV campaign was effective in curtailing the outbreak. The mean estimate for the attack rate in Bedouin children under 10 at the end of 2014 was 42 % (22-65 %), whereas without the campaign the mean projected attack rate was 57 % (35-74 %). The campaign also likely shortened the duration of the outbreak by a mean estimate of 309 (2-846) days. A faster initiation of the OPV campaign could have reduced the incidence of WPV even if a lower coverage was reached, at the risk of prolonging the outbreak. OPV campaigns are essential for interrupting WPV transmission, even in a developed country setting with a high coverage of IPV. In this setting, establishing ES of WPV circulation is particularly crucial for early detection and containment of an outbreak.
Chenais, Erika; Sternberg-Lewerin, Susanna; Boqvist, Sofia; Emanuelson, Ulf; Aliro, Tonny; Tejler, Emma; Cocca, Giampaolo; Masembe, Charles; Ståhl, Karl
2015-01-01
Animal diseases impact negatively on households and on national economies. In low-income countries, this pertains especially to socio-economic effects on household level. To control animal diseases and mitigate their impact, it is necessary to understand the epidemiology of the disease in its local context. Such understanding, gained through disease surveillance, is often lacking in resource-poor settings. Alternative surveillance methods have been developed to overcome some of the hurdles obstructing surveillance. The objective of this study was to evaluate and qualitatively compare three methods for surveillance of acute infectious diseases using African swine fever in northern Uganda as an example. Report-driven outbreak investigations, participatory rural appraisals (PRAs), and a household survey using a smartphone application were evaluated. All three methods had good disease-detecting capacity, and each of them detected many more outbreaks compared to those reported to the World Organization for Animal Health during the same time period. Apparent mortality rates were similar for the three methods although highest for the report-driven outbreak investigations, followed by the PRAs, and then the household survey. The three methods have different characteristics and the method of choice will depend on the surveillance objective. The optimal situation might be achieved by a combination of the methods: outbreak detection via smartphone-based real-time surveillance, outbreak investigation for collection of biological samples, and a PRA for a better understanding of the epidemiology of the specific outbreak. All three methods require initial investments and continuous efforts. The sustainability of the surveillance system should, therefore, be carefully evaluated before making such investments.
Echeita, M. A.; Usera, M. A.
1998-01-01
Salmonella enterica serotype Typhi strains belonging to eight different outbreaks of typhoid fever that occurred in Spain between 1989 and 1994 were analyzed by ribotyping and pulsed-field gel electrophoresis. For three outbreaks, two different patterns were detected for each outbreak. The partial digestion analysis by the intron-encoded endonuclease I-CeuI of the two different strains from each outbreak provided an excellent tool for examining the organization of the genomes of epidemiologically related strains. S. enterica serotype Typhi seems to be more susceptible than other serotypes to genetic rearrangements produced by homologous recombinations between rrn operons; these rearrangements do not substantially alter the stability or survival of the bacterium. We conclude that genetic rearrangements can occur during the emergence of an outbreak. PMID:9650981
Pseudo-Outbreak of Actinomyces graevenitzii Associated with Bronchoscopy
Peaper, David R.; Havill, Nancy L.; Aniskiewicz, Michael; Callan, Deborah; Pop, Olivia; Towle, Dana
2014-01-01
Outbreaks and pseudo-outbreaks of infection related to bronchoscopy typically involve Gram-negative bacteria, Mycobacterium species or Legionella species. We report an unusual bronchoscopy-related pseudo-outbreak due to Actinomyces graevenitzii. Extensive epidemiological and microbiological investigation failed to identify a common source. Strain typing revealed that the cluster was comprised of heterogeneous strains of A. graevenitzii. A change in laboratory procedures for Actinomyces cultures was coincident with the emergence of the pseudo-outbreak, and we determined that A. graevenitzii isolates more readily adopted a white, dry, molar tooth appearance on anaerobic colistin nalidixic acid (CNA) agar which likely facilitated its detection and identification in bronchoscopic specimens. This unusual pseudo-outbreak was related to frequent requests of bronchoscopists for Actinomyces cultures combined with a change in microbiology laboratory practices. PMID:25355767
Increase in Multistate Foodborne Disease Outbreaks-United States, 1973-2010.
Nguyen, Von D; Bennett, Sarah D; Mungai, Elisabeth; Gieraltowski, Laura; Hise, Kelley; Gould, L Hannah
2015-11-01
Changes in food production and distribution have increased opportunities for foods contaminated early in the supply chain to be distributed widely, increasing the possibility of multistate outbreaks. In recent decades, surveillance systems for foodborne disease have been improved, allowing officials to more effectively identify related cases and to trace and identify an outbreak's source. We reviewed multistate foodborne disease outbreaks reported to the Centers for Disease Control and Prevention's Foodborne Disease Outbreak Surveillance System during 1973-2010. We calculated the percentage of multistate foodborne disease outbreaks relative to all foodborne disease outbreaks and described characteristics of multistate outbreaks, including the etiologic agents and implicated foods. Multistate outbreaks accounted for 234 (0.8%) of 27,755 foodborne disease outbreaks, 24,003 (3%) of 700,600 outbreak-associated illnesses, 2839 (10%) of 29,756 outbreak-associated hospitalizations, and 99 (16%) of 628 outbreak-associated deaths. The median annual number of multistate outbreaks increased from 2.5 during 1973-1980 to 13.5 during 2001-2010; the number of multistate outbreak-associated illnesses, hospitalizations, and deaths also increased. Most multistate outbreaks were caused by Salmonella (47%) and Shiga toxin-producing Escherichia coli (26%). Foods most commonly implicated were beef (22%), fruits (13%), and leafy vegetables (13%). The number of identified and reported multistate foodborne disease outbreaks has increased. Improvements in detection, investigation, and reporting of foodborne disease outbreaks help explain the increasing number of reported multistate outbreaks and the increasing percentage of outbreaks that were multistate. Knowing the etiologic agents and foods responsible for multistate outbreaks can help to identify sources of food contamination so that the safety of the food supply can be improved.
Technical description of RODS: a real-time public health surveillance system.
Tsui, Fu-Chiang; Espino, Jeremy U; Dato, Virginia M; Gesteland, Per H; Hutman, Judith; Wagner, Michael M
2003-01-01
This report describes the design and implementation of the Real-time Outbreak and Disease Surveillance (RODS) system, a computer-based public health surveillance system for early detection of disease outbreaks. Hospitals send RODS data from clinical encounters over virtual private networks and leased lines using the Health Level 7 (HL7) message protocol. The data are sent in real time. RODS automatically classifies the registration chief complaint from the visit into one of seven syndrome categories using Bayesian classifiers. It stores the data in a relational database, aggregates the data for analysis using data warehousing techniques, applies univariate and multivariate statistical detection algorithms to the data, and alerts users of when the algorithms identify anomalous patterns in the syndrome counts. RODS also has a Web-based user interface that supports temporal and spatial analyses. RODS processes sales of over-the-counter health care products in a similar manner but receives such data in batch mode on a daily basis. RODS was used during the 2002 Winter Olympics and currently operates in two states-Pennsylvania and Utah. It has been and continues to be a resource for implementing, evaluating, and applying new methods of public health surveillance.
von Zuben, Andrea Paula Bruno; Angerami, Rodrigo Nogueira; Castagna, Claudio; Baldini, Marisa Bevilacqua Denardi; Donalisio, Maria Rita
2014-01-01
Early detection of American visceral leishmaniasis (AVL) outbreak in animals is crucial for controlling this disease in non-endemic areas. Epidemiological surveillance (2009-2012) was performed in Campinas, State of São Paulo, Brazil. In 2009, Leishmania chagasi was positively identified in four dogs. Entomological research and three serological studies (2010-2012) were undertaken as monitoring measures; these approaches revealed a moderate prevalence of Leishmania present in 4% of the canine population. Nyssomyia whitmani and Lutzomyia longipalpis were the predominant species identified. Detection of an AVL outbreak in dogs in an area with an evolving natural landscape containing sand flies is crucial for control programs.
Salmonellosis Outbreak Traced to Playground Sand, Australia, 2007–2009
Musto, Jennie; Hogg, Geoff; Janssen, Monika; Rose, Karrie
2012-01-01
A community outbreak of gastroenteritis in Australia during 2007–2009 was caused by ingestion of playground sand contaminated with Salmonella enterica Paratyphi B, variant Java. The bacterium was also isolated from local wildlife. Findings support consideration of nonfood sources during salmonellosis outbreak investigations and indicate transmission through the animal–human interface. PMID:22709539
Control Measures Used during Lymphogranuloma Venereum Outbreak, Europe
Hulscher, Marlies E.J.L.; Vos, Dieuwke; van de Laar, Marita J.W.; Fenton, Kevin A.; van Steenbergen, Jim E.; van der Meer, Jos W.M.; Grol, Richard P.T.M.
2008-01-01
To assess the response to the reemergence of lymphogranuloma venereum, we conducted a cross-sectional survey by administering a structured questionnaire to representatives from 26 European countries. Responses were received from 18 countries. The ability to respond quickly and the measures used for outbreak detection and control varied. Evidence-based criteria were not consistently used to develop recommendations. We did not develop criteria to determine the effectiveness of the recommendations. The degree of preparedness for an unexpected outbreak, as well as the ability of countries to respond quickly to alerts, varied, which indicates weaknesses in the ability to control an outbreak. More guidance is needed to implement and evaluate control measures used during international outbreaks. PMID:18394274
James, Ameh S; Todd, Shawn; Pollak, Nina M; Marsh, Glenn A; Macdonald, Joanne
2018-04-23
The 2014/2015 Ebolavirus outbreak resulted in more than 28,000 cases and 11,323 reported deaths, as of March 2016. Domestic transmission of the Guinea strain associated with the outbreak occurred mainly in six African countries, and international transmission was reported in four countries. Outbreak management was limited by the inability to rapidly diagnose infected cases. A further fifteen countries in Africa are predicted to be at risk of Ebolavirus outbreaks in the future as a consequence of climate change and urbanization. Early detection of cases and reduction of transmission rates is critical to prevent and manage future severe outbreaks. We designed a rapid assay for detection of Ebolavirus using recombinase polymerase amplification, a rapid isothermal amplification technology that can be combined with portable lateral flow detection technology. The developed rapid assay operates in 30 min and was comparable with real-time TaqMan™ PCR. Designed, screened, selected and optimized oligonucleotides using the NP coding region from Ebola Zaire virus (Guinea strain). We determined the analytical sensitivity of our Ebola rapid molecular test by testing selected primers and probe with tenfold serial dilutions (1.34 × 10 10- 1.34 × 10 1 copies/μL) of cloned NP gene from Mayinga strain of Zaire ebolavirus in pCAGGS vector, and serially diluted cultured Ebolavirus as established by real-time TaqMan™ PCR that was performed using ABI7500 in Fast Mode. We tested extracted and reverse transcribed RNA from cultured Zaire ebolavirus strains - Mayinga, Gueckedou C05, Gueckedou C07, Makona, Kissidougou and Kiwit. We determined the analytical specificity of our assay with related viruses: Marburg, Ebola Reston and Ebola Sudan. We further tested for Dengue virus 1-4, Plasmodium falciparum and West Nile Virus (Kunjin strain). The assay had a detection limit of 134 copies per μL of plasmid containing the NP gene of Ebolavirus Mayinga, and cultured Ebolavirus and was highly specific for the Zaire ebolavirus species, including the Guinea strain responsible for the 2014/2015 outbreak. The assay did not detect related viruses like Marburg, Reston, or Sudan viruses, and other pathogens likely to be isolated from clinical samples. Our assay could be suitable for implementation in district and primary health laboratories, as only a heating block and centrifuge is required for operation. The technique could provide a pathway for rapid screening of patients and animals for improved management of outbreaks.
Yellow Fever outbreak in Darfur, Sudan in October 2012; the initial outbreak investigation report.
Soghaier, Mohammed A; Hagar, Ahmed; Abbas, Mohammed A; Elmangory, Mutasim M; Eltahir, Khalid M; Sall, Amadou A
2013-10-01
Sudan is subject to repeated outbreaks, including Viral Hemorrhagic Fever (VHF), which is considered to be a very serious illness. Yellow Fever (YF) outbreaks in Sudan have been reported from the 1940s through 2005. In 2012, a new outbreak of YF occurred in the Darfur region. To identify the potential for an outbreak, to diagnose the disease and to be able to recognize its cause among the initial reported cases. >This is a descriptive and investigative field study that applies standard communicable disease outbreak investigation steps. The study involved clinical, serological, entomological and environmental surveys. The field investigation confirmed the outbreak and identified its cause to be YF. National surveillance systems should be strong enough to detect VHFs in a timely manner. Local health facilities should be prepared to promptly treat the initial cases because the case fatality ratios (CFRs) are usually very high among the index cases. Copyright © 2013 King Saud Bin Abdulaziz University for Health Sciences. Published by Elsevier Ltd. All rights reserved.
Two outbreaks of classical swine fever in wild boar in France.
Pol, F; Rossi, S; Mesplède, A; Kuntz-Simon, G; Le Potier, M-F
2008-06-21
In 2002 and 2003, two successive outbreaks of classical swine fever were declared in wild boar in northern France. The first was in Moselle, near the town of Thionville and the border with Luxembourg, and the second was in the northern Vosges area, near the German border. The outbreaks were investigated by serological and virological diagnosis of dead or shot animals. Hunting restrictions were applied to limit the spread of the outbreaks. The virus was detected eight times between April and July 2002 in the Thionville area, an area well delimited by natural or artificial barriers such as rivers or highways. Cooperation between the authorities concerned was good, and hunting restrictions were applied for one year. No virus was detected after July 2002 and the Thionville outbreak was officially considered over in March 2005. In the northern Vosges the situation was different, with no barriers to animal movements, continuous forest, difficulties in establishing hunting restrictions in this huge area, and the circulation of the virus in Germany close to the frontier. Virus of a different strain from that isolated in the Thionville outbreak was still being isolated in the northern Vosges in 2004, and owing to the failure of the hunting restrictions, the French health authorities decided to vaccinate wild boar.
An outbreak of food poisoning due to egg yolk reaction-negative Staphylococcus aureus.
Miwa, N; Kawamura, A; Masuda, T; Akiyama, M
2001-03-20
An outbreak of staphylococcal food poisoning due to an egg yolk (EY) reaction-negative strain occurred in Japan. Twenty-one of 53 dam construction workers who ate boxed lunches prepared at their company cafeteria became ill, and eight required hospital treatment. The outbreak showed a typical incubation time (1.5-4 h with a median time of 2.7 h) and symptoms (vomiting and diarrhea) of staphylococcal food poisoning. Staphylococcus aureus, which produces staphylococcal enterotoxin (SE) A, was isolated from four fecal specimens of eight patients tested. Scrambled egg in the boxed lunches contained 20-40 ng/g of SEA, and 3.0 x 10(9)/g of viable S. aureus cells that produced this toxin. All isolates from patients and the food were EY reaction-negative, coagulase type II, and showed the same restriction fragment length polymorphism (RFLP) pattern. We concluded that the outbreak was caused by scrambled egg contaminated with EY reaction-negative S. aureus. In Japan, outbreaks of staphylococcal food poisoning are mainly caused by EY reaction-positive S. aureus, and EY reaction-negative colonies grown on agar plates containing EY are usually not analyzed further for detection of S. aureus. The present outbreak suggested that EY reaction-negative isolates should be subjected to further analysis to detect the causative agents of staphylococcal food poisoning.
Meynard, Jean-Baptiste; Chaudet, Hervé; Texier, Gaetan; Ardillon, Vanessa; Ravachol, Françoise; Deparis, Xavier; Jefferson, Henry; Dussart, Philippe; Morvan, Jacques; Boutin, Jean-Paul
2008-01-01
Background A dengue fever outbreak occured in French Guiana in 2006. The objectives were to study the value of a syndromic surveillance system set up within the armed forces, compared to the traditional clinical surveillance system during this outbreak, to highlight issues involved in comparing military and civilian surveillance systems and to discuss the interest of syndromic surveillance for public health response. Methods Military syndromic surveillance allows the surveillance of suspected dengue fever cases among the 3,000 armed forces personnel. Within the same population, clinical surveillance uses several definition criteria for dengue fever cases, depending on the epidemiological situation. Civilian laboratory surveillance allows the surveillance of biologically confirmed cases, within the 200,000 inhabitants. Results It was shown that syndromic surveillance detected the dengue fever outbreak several weeks before clinical surveillance, allowing quick and effective enhancement of vector control within the armed forces. Syndromic surveillance was also found to have detected the outbreak before civilian laboratory surveillance. Conclusion Military syndromic surveillance allowed an early warning for this outbreak to be issued, enabling a quicker public health response by the armed forces. Civilian surveillance system has since introduced syndromic surveillance as part of its surveillance strategy. This should enable quicker public health responses in the future. PMID:18597694
Laboratory-Based Prospective Surveillance for Community Outbreaks of Shigella spp. in Argentina
Viñas, María R.; Tuduri, Ezequiel; Galar, Alicia; Yih, Katherine; Pichel, Mariana; Stelling, John; Brengi, Silvina P.; Della Gaspera, Anabella; van der Ploeg, Claudia; Bruno, Susana; Rogé, Ariel; Caffer, María I.; Kulldorff, Martin; Galas, Marcelo
2013-01-01
Background To implement effective control measures, timely outbreak detection is essential. Shigella is the most common cause of bacterial diarrhea in Argentina. Highly resistant clones of Shigella have emerged, and outbreaks have been recognized in closed settings and in whole communities. We hereby report our experience with an evolving, integrated, laboratory-based, near real-time surveillance system operating in six contiguous provinces of Argentina during April 2009 to March 2012. Methodology To detect localized shigellosis outbreaks timely, we used the prospective space-time permutation scan statistic algorithm of SaTScan, embedded in WHONET software. Twenty three laboratories sent updated Shigella data on a weekly basis to the National Reference Laboratory. Cluster detection analysis was performed at several taxonomic levels: for all Shigella spp., for serotypes within species and for antimicrobial resistance phenotypes within species. Shigella isolates associated with statistically significant signals (clusters in time/space with recurrence interval ≥365 days) were subtyped by pulsed field gel electrophoresis (PFGE) using PulseNet protocols. Principal Findings In three years of active surveillance, our system detected 32 statistically significant events, 26 of them identified before hospital staff was aware of any unexpected increase in the number of Shigella isolates. Twenty-six signals were investigated by PFGE, which confirmed a close relationship among the isolates for 22 events (84.6%). Seven events were investigated epidemiologically, which revealed links among the patients. Seventeen events were found at the resistance profile level. The system detected events of public health importance: infrequent resistance profiles, long-lasting and/or re-emergent clusters and events important for their duration or size, which were reported to local public health authorities. Conclusions/Significance The WHONET-SaTScan system may serve as a model for surveillance and can be applied to other pathogens, implemented by other networks, and scaled up to national and international levels for early detection and control of outbreaks. PMID:24349586
Laboratory-based prospective surveillance for community outbreaks of Shigella spp. in Argentina.
Viñas, María R; Tuduri, Ezequiel; Galar, Alicia; Yih, Katherine; Pichel, Mariana; Stelling, John; Brengi, Silvina P; Della Gaspera, Anabella; van der Ploeg, Claudia; Bruno, Susana; Rogé, Ariel; Caffer, María I; Kulldorff, Martin; Galas, Marcelo
2013-01-01
To implement effective control measures, timely outbreak detection is essential. Shigella is the most common cause of bacterial diarrhea in Argentina. Highly resistant clones of Shigella have emerged, and outbreaks have been recognized in closed settings and in whole communities. We hereby report our experience with an evolving, integrated, laboratory-based, near real-time surveillance system operating in six contiguous provinces of Argentina during April 2009 to March 2012. To detect localized shigellosis outbreaks timely, we used the prospective space-time permutation scan statistic algorithm of SaTScan, embedded in WHONET software. Twenty three laboratories sent updated Shigella data on a weekly basis to the National Reference Laboratory. Cluster detection analysis was performed at several taxonomic levels: for all Shigella spp., for serotypes within species and for antimicrobial resistance phenotypes within species. Shigella isolates associated with statistically significant signals (clusters in time/space with recurrence interval ≥365 days) were subtyped by pulsed field gel electrophoresis (PFGE) using PulseNet protocols. In three years of active surveillance, our system detected 32 statistically significant events, 26 of them identified before hospital staff was aware of any unexpected increase in the number of Shigella isolates. Twenty-six signals were investigated by PFGE, which confirmed a close relationship among the isolates for 22 events (84.6%). Seven events were investigated epidemiologically, which revealed links among the patients. Seventeen events were found at the resistance profile level. The system detected events of public health importance: infrequent resistance profiles, long-lasting and/or re-emergent clusters and events important for their duration or size, which were reported to local public health authorities. The WHONET-SaTScan system may serve as a model for surveillance and can be applied to other pathogens, implemented by other networks, and scaled up to national and international levels for early detection and control of outbreaks.
Hospital-acquired listeriosis outbreak caused by contaminated diced celery--Texas, 2010.
Gaul, Linda Knudson; Farag, Noha H; Shim, Trudi; Kingsley, Monica A; Silk, Benjamin J; Hyytia-Trees, Eija
2013-01-01
Listeria monocytogenes causes often-fatal infections affecting mainly immunocompromised persons. Sources of hospital-acquired listeriosis outbreaks can be difficult to identify. We investigated a listeriosis outbreak spanning 7 months and involving 5 hospitals. Outbreak-related cases were identified by pulsed-field gel electrophoresis (PFGE) and confirmed by multiple-locus variable-number tandem-repeat analysis (MLVA). We conducted patient interviews, medical records reviews, and hospital food source evaluations. Food and environmental specimens were collected at a hospital (hospital A) where 6 patients had been admitted before listeriosis onset; these specimens were tested by culture, polymerase chain reaction (PCR), and PFGE. We collected and tested food and environmental samples at the implicated processing facility. Ten outbreak-related patients were immunocompromised by ≥1 underlying conditions or treatments; 5 died. All patients had been admitted to or visited an acute-care hospital during their possible incubation periods. The outbreak strain of L. monocytogenes was isolated from chicken salad and its diced celery ingredient at hospital A, and in 19 of >200 swabs of multiple surfaces and in 8 of 11 diced celery products at the processing plant. PCR testing detected Listeria in only 3 of 10 environmental and food samples from which it was isolated by culturing. The facility was closed, products were recalled, and the outbreak ended. Contaminated diced celery caused a baffling, lengthy outbreak of hospital-acquired listeriosis. PCR testing often failed to detect the pathogen, suggesting its reliability should be further evaluated. Listeriosis risk should be considered in fresh produce selections for immunocompromised patients.
Yan, R; He, B; Yao, F Y; Xiang, Z L; He, H Q; Xie, S Y; Feng, Y
2018-03-10
Objective: To investigate the epidemiological characteristics of measles outbreak caused by genotype D8 virus in Pinghu city of Zhejiang province, and provide evidence for the control of the outbreak. Methods: The measles outbreak data were collected through National Measles Surveillance System. The outpatient records and admission records were checked, field investigation and outbreak response were conducted. Blood samples in acute phase and swab specimens were collected from the patients for laboratory testing, including serology test, RNA extraction and amplification, measles virus isolation and genotype identification. Software SPSS 17.0 and Excel 2016 were used for data analysis. Results: A total of 10 confirmed measles cases were reported in Pinghu city, and 8 cases were aged >40 years. Six blood samples were collected, in which 5 were measles D8 virus positive and 1 was negative in measles virus detection. There were epidemiological links among 10 cases which occurred in a factory, a hospital and a family at the same time. There was no statistical difference in symptoms among cases caused by D8 virus and H1a virus. After the emergent measles vaccination, the measles outbreak was effectively controlled. Conclusion: Untimely response due to the uneasy detection of measles cases in the early stage, nosocomial infection and weak barrier of measles immunity in adults might be the main reasons for this outbreak. Measles vaccination is effective in the prevention of measles D8 virus infection. It is necessary to strengthen measles genotype monitoring for the tracing of infection source and control of outbreaks.
NASA Technical Reports Server (NTRS)
Hall, R. C. (Principal Investigator); Wert, S. L.; Koerber, T. W.
1974-01-01
The author has identified the following significant results. Analysis of ERTS-1 imagery with underflight aerial photo support including U-2, in the Sierra Nevada Mountains of California, indicates promising possibilities of detecting and monitoring forest insect outbreaks visually with some mechanical support utilizing the VP-8 image analyzer. Visually, it is possible at a scale of 1:1,000,000 to discriminate between large areas of damaged and undamaged forests; timbered and non-timbered areas; pasture land and cultivated fields; desert and riparian vegetation. At a scale of 1:80,000 it is possible to distinguish among three classes of tree mortality; defoliated and undefoliated areas; non-host mixed conifers; and mountain meadows, rock domes, lakes and glaciers. Machine tests showed significant differences in image densities among various bands and mortality areas.
García-Bocanegra, I; Belkhiria, J; Napp, S; Cano-Terriza, D; Jiménez-Ruiz, S; Martínez-López, B
2018-04-01
During the last decade, West Nile virus (WNV) outbreaks have increased sharply in both horses and human in Europe. The aims of this study were to evaluate characteristics and spatio-temporal distribution of WNV outbreaks in horses in Spain between 2010 and 2016 in order to identify the environmental variables most associated with WNV occurrence and to generate high-resolution WNV suitability maps to inform risk-based surveillance strategies in this country. Between August 2010 and November 2016, a total of 403 WNV suspected cases were investigated, of which, 177 (43.9%) were laboratory confirmed. Mean values of morbidity, mortality and case fatality rates were 7.5%, 1.6% and 21.2%, respectively. The most common clinical symptoms were as follows: tiredness/apathy, recumbency, muscular tremor, ataxia, incoordination and hyperaesthesia. The outbreaks confirmed during the last 7 years, with detection of WNV RNA lineage 1 in 2010, 2012, 2013, 2015 and 2016, suggest an endemic circulation of the virus in Spain. The spatio-temporal distribution of WNV outbreaks in Spain was not homogeneous, as most of them (92.7%) were concentrated in western part of Andalusia (southern Spain) and significant clusters were detected in this region in two non-consecutive years. These findings were supported by the results of the space-time scan statistics permutation model. A presence-only MaxEnt ecological niche model was used to generate a suitability map for WNV occurrence in Andalusia. The most important predictors selected by the Ecological Niche Modeling were as follows: mean annual temperature (49.5% contribution), presence of Culex pipiens (19.5% contribution), mean annual precipitation (16.1% contribution) and distance to Ramsar wetlands (14.9% contribution). Our results constitute an important step for understanding WNV emergence and spread in Spain and will provide valuable information for the development of more cost-effective surveillance and control programmes and improve the protection of horse and human populations in WNV-endemic areas. © 2017 Blackwell Verlag GmbH.
Constructing rigorous and broad biosurveillance networks for detecting emerging zoonotic outbreaks
DOE Office of Scientific and Technical Information (OSTI.GOV)
Brown, Mac; Moore, Leslie; McMahon, Benjamin
Determining optimal surveillance networks for an emerging pathogen is difficult since it is not known beforehand what the characteristics of a pathogen will be or where it will emerge. The resources for surveillance of infectious diseases in animals and wildlife are often limited and mathematical modeling can play a supporting role in examining a wide range of scenarios of pathogen spread. We demonstrate how a hierarchy of mathematical and statistical tools can be used in surveillance planning help guide successful surveillance and mitigation policies for a wide range of zoonotic pathogens. The model forecasts can help clarify the complexities ofmore » potential scenarios, and optimize biosurveillance programs for rapidly detecting infectious diseases. Using the highly pathogenic zoonotic H5N1 avian influenza 2006-2007 epidemic in Nigeria as an example, we determined the risk for infection for localized areas in an outbreak and designed biosurveillance stations that are effective for different pathogen strains and a range of possible outbreak locations. We created a general multi-scale, multi-host stochastic SEIR epidemiological network model, with both short and long-range movement, to simulate the spread of an infectious disease through Nigerian human, poultry, backyard duck, and wild bird populations. We chose parameter ranges specific to avian influenza (but not to a particular strain) and used a Latin hypercube sample experimental design to investigate epidemic predictions in a thousand simulations. We ranked the risk of local regions by the number of times they became infected in the ensemble of simulations. These spatial statistics were then complied into a potential risk map of infection. Finally, we validated the results with a known outbreak, using spatial analysis of all the simulation runs to show the progression matched closely with the observed location of the farms infected in the 2006-2007 epidemic.« less
Constructing rigorous and broad biosurveillance networks for detecting emerging zoonotic outbreaks
Brown, Mac; Moore, Leslie; McMahon, Benjamin; ...
2015-05-06
Determining optimal surveillance networks for an emerging pathogen is difficult since it is not known beforehand what the characteristics of a pathogen will be or where it will emerge. The resources for surveillance of infectious diseases in animals and wildlife are often limited and mathematical modeling can play a supporting role in examining a wide range of scenarios of pathogen spread. We demonstrate how a hierarchy of mathematical and statistical tools can be used in surveillance planning help guide successful surveillance and mitigation policies for a wide range of zoonotic pathogens. The model forecasts can help clarify the complexities ofmore » potential scenarios, and optimize biosurveillance programs for rapidly detecting infectious diseases. Using the highly pathogenic zoonotic H5N1 avian influenza 2006-2007 epidemic in Nigeria as an example, we determined the risk for infection for localized areas in an outbreak and designed biosurveillance stations that are effective for different pathogen strains and a range of possible outbreak locations. We created a general multi-scale, multi-host stochastic SEIR epidemiological network model, with both short and long-range movement, to simulate the spread of an infectious disease through Nigerian human, poultry, backyard duck, and wild bird populations. We chose parameter ranges specific to avian influenza (but not to a particular strain) and used a Latin hypercube sample experimental design to investigate epidemic predictions in a thousand simulations. We ranked the risk of local regions by the number of times they became infected in the ensemble of simulations. These spatial statistics were then complied into a potential risk map of infection. Finally, we validated the results with a known outbreak, using spatial analysis of all the simulation runs to show the progression matched closely with the observed location of the farms infected in the 2006-2007 epidemic.« less
Characterization of synoptic patterns causing dust outbreaks that affect the Arabian Peninsula
NASA Astrophysics Data System (ADS)
Hermida, L.; Merino, A.; Sánchez, J. L.; Fernández-González, S.; García-Ortega, E.; López, L.
2018-01-01
Dust storms pose serious weather hazards in arid and semiarid regions of the earth. Understanding the main synoptic conditions that give rise to dust outbreaks is important for issuing forecasts and warnings to the public in cases of severe storms. The aim of the present study is to determine synoptic patterns that are associated with or even favor dust outbreaks over the Arabian Peninsula. In this respect, red-green-blue dust composite images from the Meteosat Second Generation (MSG) satellite are used to detect dust outbreaks affecting the Arabian Peninsula, with possible influences in southwestern Asia and northeastern Africa, between 2005 and 2013. The Meteosat imagery yielded a sample of 95 dust storm days. Meteorological fields from NCEP/NCAR reanalysis data of wind fields at 10 m and 250 hPa, mean sea level pressure, and geopotential heights at 850 and 500 hPa were obtained for the dust storm days. Using principal component analysis in T-mode and non-hierarchical k-means clustering, we obtained four major atmospheric circulation patterns associated with dust outbreaks during the study days. Cluster 4 had the largest number of days with dust events, which were constrained to summer, and cluster 3 had the fewest. In clusters 1, 2 and 3, the jet stream favored the entry of a low-pressure area or trough that varied in location between the three clusters. Their most northerly location was found in cluster 4, along with an extensive low-pressure area supporting strong winds over the Arabian Peninsula. The spatial distribution of aerosol optical depth for each cluster obtained was characterized using the Moderate Resolution Imaging Spectroradiometer data. Then, using METAR stations, clusters were also characterized in terms of frequency and visibility.
Sivan, Arun; Shriram, A N; Sugunan, A P; Anwesh, Maile; Muruganandam, N; Kartik, C; Vijayachari, P
2016-04-01
From May to June 2014, an outbreak of dengue virus (DENV) illness occurred in the Havelock Island, South Andaman. Entomological investigations were undertaken during the peak of the outbreak, from 26th May-4th June, to identify the primary vector(s) involved in the transmission so that appropriate public health measures could be implemented. Adult mosquitoes were collected by BG-Sentinel traps in houses and neighborhoods of clinically ill patients. Water holding containers were inspected for the presence of mosquito larvae and pupae. Adult mosquitoes were analyzed by RT-PCR for the presence of nucleic acids of DENV and CHIKV. A total of 498 mosquitoes were collected and processed in 27 pools. The species composition comprised of 58.3% Aedes albopictus, 7.5% Aedes aegypti and 4.2% Aedes edwardsi and 3.1% constituted others. Two A. albopictus pools were found to be positive for DENV RNA. Sequencing of the RT PCR 511 base pair amplicon positive samples showed homology with DENV-3, suggesting that serotype-3 was responsible for the outbreak and A. albopictus was the primary vector responsible. This was supported by high container (10.1%), premise (25.4%) and Breteau (27.9) indices, with miscellaneous receptacles (2.4%), tree holes (1.2%) and discarded tires (1.2%) registering relatively higher container indices. This is the first report of detection of DENV in A. albopictus from Andaman and Nicobar Islands. Copyright © 2016 Elsevier B.V. All rights reserved.
Elkins, C A; Kotewicz, M L; Jackson, S A; Lacher, D W; Abu-Ali, G S; Patel, I R
2013-01-01
Modern risk control and food safety practices involving food-borne bacterial pathogens are benefiting from new genomic technologies for rapid, yet highly specific, strain characterisations. Within the United States Food and Drug Administration (USFDA) Center for Food Safety and Applied Nutrition (CFSAN), optical genome mapping and DNA microarray genotyping have been used for several years to quickly assess genomic architecture and gene content, respectively, for outbreak strain subtyping and to enhance retrospective trace-back analyses. The application and relative utility of each method varies with outbreak scenario and the suspect pathogen, with comparative analytical power enhanced by database scale and depth. Integration of these two technologies allows high-resolution scrutiny of the genomic landscapes of enteric food-borne pathogens with notable examples including Shiga toxin-producing Escherichia coli (STEC) and Salmonella enterica serovars from a variety of food commodities. Moreover, the recent application of whole genome sequencing technologies to food-borne pathogen outbreaks and surveillance has enhanced resolution to the single nucleotide scale. This new wealth of sequence data will support more refined next-generation custom microarray designs, targeted re-sequencing and "genomic signature recognition" approaches involving a combination of genes and single nucleotide polymorphism detection to distil strain-specific fingerprinting to a minimised scale. This paper examines the utility of microarrays and optical mapping in analysing outbreaks, reviews best practices and the limits of these technologies for pathogen differentiation, and it considers future integration with whole genome sequencing efforts.
Newman, Scott H.; Iverson, Samuel A.; Takekawa, John Y.; Gilbert, Martin; Prosser, Diann J.; Batbayar, Nyambyar; Natsagdorj, Tseveenmyadag; Douglas, David C.
2009-01-01
Evaluating the potential involvement of wild avifauna in the emergence of highly pathogenic avian influenza H5N1 (hereafter H5N1) requires detailed analyses of temporal and spatial relationships between wild bird movements and disease emergence. The death of wild swans (Cygnus spp.) has been the first indicator of the presence of H5N1 in various Asian and European countries; however their role in the geographic spread of the disease remains poorly understood. We marked 10 whooper swans (Cygnus cygnus) with GPS transmitters in northeastern Mongolia during autumn 2006 and tracked their migratory movements in relation to H5N1 outbreaks. The prevalence of H5N1 outbreaks among poultry in eastern Asia during 2003-2007 peaked during winter, concurrent with whooper swan movements into regions of high poultry density. However outbreaks involving poultry were detected year round, indicating disease perpetuation independent of migratory waterbird presence. In contrast, H5N1 outbreaks involving whooper swans, as well as other migratory waterbirds that succumbed to the disease in eastern Asia, tended to occur during seasons (late spring and summer) and in habitats (areas of natural vegetation) where their potential for contact with poultry is very low to nonexistent. Given what is known about the susceptibility of swans to H5N1, and on the basis of the chronology and rates of whooper swan migration movements, we conclude that although there is broad spatial overlap between whooper swan distributions and H5N1 outbreak locations in eastern Asia, the likelihood of direct transmission between these groups is extremely low. Thus, our data support the hypothesis that swans are best viewed as sentinel species, and moreover, that in eastern Asia, it is most likely that their infections occurred through contact with asymptomatic migratory hosts (e.g., wild ducks) at or near their breeding grounds.
Newman, Scott H; Iverson, Samuel A; Takekawa, John Y; Gilbert, Martin; Prosser, Diann J; Batbayar, Nyambyar; Natsagdorj, Tseveenmyadag; Douglas, David C
2009-05-28
Evaluating the potential involvement of wild avifauna in the emergence of highly pathogenic avian influenza H5N1 (hereafter H5N1) requires detailed analyses of temporal and spatial relationships between wild bird movements and disease emergence. The death of wild swans (Cygnus spp.) has been the first indicator of the presence of H5N1 in various Asian and European countries; however their role in the geographic spread of the disease remains poorly understood. We marked 10 whooper swans (Cygnus cygnus) with GPS transmitters in northeastern Mongolia during autumn 2006 and tracked their migratory movements in relation to H5N1 outbreaks. The prevalence of H5N1 outbreaks among poultry in eastern Asia during 2003-2007 peaked during winter, concurrent with whooper swan movements into regions of high poultry density. However outbreaks involving poultry were detected year round, indicating disease perpetuation independent of migratory waterbird presence. In contrast, H5N1 outbreaks involving whooper swans, as well as other migratory waterbirds that succumbed to the disease in eastern Asia, tended to occur during seasons (late spring and summer) and in habitats (areas of natural vegetation) where their potential for contact with poultry is very low to nonexistent. Given what is known about the susceptibility of swans to H5N1, and on the basis of the chronology and rates of whooper swan migration movements, we conclude that although there is broad spatial overlap between whooper swan distributions and H5N1 outbreak locations in eastern Asia, the likelihood of direct transmission between these groups is extremely low. Thus, our data support the hypothesis that swans are best viewed as sentinel species, and moreover, that in eastern Asia, it is most likely that their infections occurred through contact with asymptomatic migratory hosts (e.g., wild ducks) at or near their breeding grounds.
Newman, Scott H.; Iverson, Samuel A.; Takekawa, John Y.; Gilbert, Martin; Prosser, Diann J.; Batbayar, Nyambyar; Natsagdorj, Tseveenmyadag; Douglas, David C.
2009-01-01
Evaluating the potential involvement of wild avifauna in the emergence of highly pathogenic avian influenza H5N1 (hereafter H5N1) requires detailed analyses of temporal and spatial relationships between wild bird movements and disease emergence. The death of wild swans (Cygnus spp.) has been the first indicator of the presence of H5N1 in various Asian and European countries; however their role in the geographic spread of the disease remains poorly understood. We marked 10 whooper swans (Cygnus cygnus) with GPS transmitters in northeastern Mongolia during autumn 2006 and tracked their migratory movements in relation to H5N1 outbreaks. The prevalence of H5N1 outbreaks among poultry in eastern Asia during 2003–2007 peaked during winter, concurrent with whooper swan movements into regions of high poultry density. However outbreaks involving poultry were detected year round, indicating disease perpetuation independent of migratory waterbird presence. In contrast, H5N1 outbreaks involving whooper swans, as well as other migratory waterbirds that succumbed to the disease in eastern Asia, tended to occur during seasons (late spring and summer) and in habitats (areas of natural vegetation) where their potential for contact with poultry is very low to nonexistent. Given what is known about the susceptibility of swans to H5N1, and on the basis of the chronology and rates of whooper swan migration movements, we conclude that although there is broad spatial overlap between whooper swan distributions and H5N1 outbreak locations in eastern Asia, the likelihood of direct transmission between these groups is extremely low. Thus, our data support the hypothesis that swans are best viewed as sentinel species, and moreover, that in eastern Asia, it is most likely that their infections occurred through contact with asymptomatic migratory hosts (e.g., wild ducks) at or near their breeding grounds. PMID:19479053
Causes of Pneumonia Epizootics among Bighorn Sheep, Western United States, 2008–2010
Highland, Margaret A.; Baker, Katherine; Cassirer, E. Frances; Anderson, Neil J.; Ramsey, Jennifer M.; Mansfield, Kristin; Bruning, Darren L.; Wolff, Peregrine; Smith, Joshua B.; Jenks, Jonathan A.
2012-01-01
Epizootic pneumonia of bighorn sheep is a devastating disease of uncertain etiology. To help clarify the etiology, we used culture and culture-independent methods to compare the prevalence of the bacterial respiratory pathogens Mannheimia haemolytica, Bibersteinia trehalosi, Pasteurella multocida, and Mycoplasma ovipneumoniae in lung tissue from 44 bighorn sheep from herds affected by 8 outbreaks in the western United States. M. ovipneumoniae, the only agent detected at significantly higher prevalence in animals from outbreaks (95%) than in animals from unaffected healthy populations (0%), was the most consistently detected agent and the only agent that exhibited single strain types within each outbreak. The other respiratory pathogens were frequently but inconsistently detected, as were several obligate anaerobic bacterial species, all of which might represent secondary or opportunistic infections that could contribute to disease severity. These data provide evidence that M. ovipneumoniae plays a primary role in the etiology of epizootic pneumonia of bighorn sheep. PMID:22377321
Clinical microbiology informatics.
Rhoads, Daniel D; Sintchenko, Vitali; Rauch, Carol A; Pantanowitz, Liron
2014-10-01
The clinical microbiology laboratory has responsibilities ranging from characterizing the causative agent in a patient's infection to helping detect global disease outbreaks. All of these processes are increasingly becoming partnered more intimately with informatics. Effective application of informatics tools can increase the accuracy, timeliness, and completeness of microbiology testing while decreasing the laboratory workload, which can lead to optimized laboratory workflow and decreased costs. Informatics is poised to be increasingly relevant in clinical microbiology, with the advent of total laboratory automation, complex instrument interfaces, electronic health records, clinical decision support tools, and the clinical implementation of microbial genome sequencing. This review discusses the diverse informatics aspects that are relevant to the clinical microbiology laboratory, including the following: the microbiology laboratory information system, decision support tools, expert systems, instrument interfaces, total laboratory automation, telemicrobiology, automated image analysis, nucleic acid sequence databases, electronic reporting of infectious agents to public health agencies, and disease outbreak surveillance. The breadth and utility of informatics tools used in clinical microbiology have made them indispensable to contemporary clinical and laboratory practice. Continued advances in technology and development of these informatics tools will further improve patient and public health care in the future. Copyright © 2014, American Society for Microbiology. All Rights Reserved.
Clinical Microbiology Informatics
Sintchenko, Vitali; Rauch, Carol A.; Pantanowitz, Liron
2014-01-01
SUMMARY The clinical microbiology laboratory has responsibilities ranging from characterizing the causative agent in a patient's infection to helping detect global disease outbreaks. All of these processes are increasingly becoming partnered more intimately with informatics. Effective application of informatics tools can increase the accuracy, timeliness, and completeness of microbiology testing while decreasing the laboratory workload, which can lead to optimized laboratory workflow and decreased costs. Informatics is poised to be increasingly relevant in clinical microbiology, with the advent of total laboratory automation, complex instrument interfaces, electronic health records, clinical decision support tools, and the clinical implementation of microbial genome sequencing. This review discusses the diverse informatics aspects that are relevant to the clinical microbiology laboratory, including the following: the microbiology laboratory information system, decision support tools, expert systems, instrument interfaces, total laboratory automation, telemicrobiology, automated image analysis, nucleic acid sequence databases, electronic reporting of infectious agents to public health agencies, and disease outbreak surveillance. The breadth and utility of informatics tools used in clinical microbiology have made them indispensable to contemporary clinical and laboratory practice. Continued advances in technology and development of these informatics tools will further improve patient and public health care in the future. PMID:25278581
Environmental Survey of Drinking Water Sources in Kampala, Uganda, during a Typhoid Fever Outbreak
Kahler, A. M.; Nansubuga, I.; Nanyunja, E. M.; Kaplan, B.; Jothikumar, N.; Routh, J.; Gómez, G. A.; Mintz, E. D.; Hill, V. R.
2017-01-01
ABSTRACT In 2015, a typhoid fever outbreak began in downtown Kampala, Uganda, and spread into adjacent districts. In response, an environmental survey of drinking water source types was conducted in areas of the city with high case numbers. A total of 122 samples was collected from 12 source types and tested for Escherichia coli, free chlorine, and conductivity. An additional 37 grab samples from seven source types and 16 paired large volume (20 liter) samples from wells and springs were also collected and tested for the presence of Salmonella enterica serovar Typhi. Escherichia coli was detected in 60% of kaveras (drinking water sold in plastic bags) and 80% of refilled water bottles; free chlorine was not detected in either source type. Most jerry cans (68%) contained E. coli and had free chlorine residuals below the WHO-recommended level of 0.5 mg/liter during outbreaks. Elevated conductivity readings for kaveras, refilled water bottles, and jerry cans (compared to treated surface water supplied by the water utility) suggested that they likely contained untreated groundwater. All unprotected springs and wells and more than 60% of protected springs contained E. coli. Water samples collected from the water utility were found to have acceptable free chlorine levels and no detectable E. coli. While S. Typhi was not detected in water samples, Salmonella spp. were detected in samples from two unprotected springs, one protected spring, and one refilled water bottle. These data provided clear evidence that unregulated vended water and groundwater represented a risk for typhoid transmission. IMPORTANCE Despite the high incidence of typhoid fever globally, relatively few outbreak investigations incorporate drinking water testing. During waterborne disease outbreaks, measurement of physical-chemical parameters, such as free chlorine residual and electrical conductivity, and of microbiological parameters, such as the presence of E. coli or the implicated etiologic agent, in drinking water samples can identify contaminated sources. This investigation indicated that unregulated vended water and groundwater sources were contaminated and were therefore a risk to consumers during the 2015 typhoid fever outbreak in Kampala. Identification of contaminated drinking water sources and sources that do not contain adequate disinfectant levels can lead to rapid targeted interventions. PMID:28970225
Zacheus, Outi; Miettinen, Ilkka T
2011-12-01
In 1997, a compulsory notification system for waterborne outbreaks was introduced in Finland. The main aim of this notification is to obtain immediate information on suspected waterborne outbreaks in order to restrict and manage the outbreak promptly. During the past ten years, there have been 67 waterborne outbreaks in Finland, mainly associated with small groundwater supplies or private wells. The number of reported waterborne outbreaks has increased since the launch of the notification system indicating that the threshold limit of outbreak detection has most probably decreased. The number of cases of illness has fulfilled the national health target, which is below 0.01% of the population, but more action is still needed to ensure the production of safe drinking water under all circumstances. Ten years accumulation of knowledge on outbreaks has revealed that a compulsory notification system is an effective tool to gather information on waterborne outbreaks. The system has also increased awareness of possible problems related to the quality of drinking water. This article summarises management and legislative actions and policy measures taken so far in Finland to reduce the number of outbreaks and cases of illness related to them.
Ashbaugh, Hayley R; Kuang, Brandon; Gadoth, Adva; Alfonso, Vivian H; Mukadi, Patrick; Doshi, Reena H; Hoff, Nicole A; Sinai, Cyrus; Mossoko, Mathias; Kebela, Benoit Ilunga; Muyembe, Jean-Jacques; Wemakoy, Emile Okitolonda; Rimoin, Anne W
2017-09-01
Ebola virus disease (EVD) can be clinically severe and highly fatal, making surveillance efforts for early disease detection of paramount importance. In areas with limited access to laboratory testing, the Integrated Disease Surveillance and Response (IDSR) strategy in the Democratic Republic of Congo (DRC) may be a vital tool in improving outbreak response. Using DRC IDSR data from the nation's four EVD outbreak periods from 2007-2014, we assessed trends of Viral Hemorrhagic Fever (VHF) and EVD differential diagnoses reportable through IDSR. With official case counts from active surveillance of EVD outbreaks, we assessed accuracy of reporting through the IDSR passive surveillance system. Although the active and passive surveillance represent distinct sets of data, the two were correlated, suggesting that passive surveillance based only on clinical evaluation may be a useful predictor of true cases prior to laboratory confirmation. There were 438 suspect VHF cases reported through the IDSR system and 416 EVD cases officially recorded across the outbreaks examined. Although collected prior to official active surveillance cases, case reporting through the IDSR during the 2007, 2008 and 2012 outbreaks coincided with official EVD epidemic curves. Additionally, all outbreak areas experienced increases in suspected cases for both malaria and typhoid fever during EVD outbreaks, underscoring the importance of training health care workers in recognising EVD differential diagnoses and the potential for co-morbidities. © 2017 John Wiley & Sons Ltd.
Schwab, K J; Neill, F H; Fankhauser, R L; Daniels, N A; Monroe, S S; Bergmire-Sweat, D A; Estes, M K; Atmar, R L
2000-01-01
"Norwalk-like viruses" (NLVs) and hepatitis A virus (HAV) are the most common causes of virus-mediated food-borne illness. Epidemiological investigations of outbreaks associated with these viruses have been hindered by the lack of available methods for the detection of NLVs and HAV in foodstuffs. Although reverse transcription (RT)-PCR methods have been useful in detecting NLVs and HAV in bivalve mollusks implicated in outbreaks, to date such methods have not been available for other foods. To address this need, we developed a method to detect NLVs and HAV recovered from food samples. The method involves washing of food samples with a guanidinium-phenol-based reagent, extraction with chloroform, and precipitation in isopropanol. Recovered viral RNA is amplified with HAV- or NLV-specific primers in RT-PCRs, using a viral RNA internal standard control to identify potential sample inhibition. By this method, 10 to 100 PCR units (estimated to be equivalent to 10(2) to 10(3) viral genome copies) of HAV and Norwalk virus seeded onto ham, turkey, and roast beef were detected. The method was applied to food samples implicated in an NLV-associated outbreak at a university cafeteria. Sliced deli ham was positive for a genogroup II NLV as determined by using both polymerase- and capsid-specific primers and probes. Sequence analysis of the PCR-amplified capsid region of the genome indicated that the sequence was identical to the sequence from virus detected in the stools of ill students. The developed method is rapid, simple, and efficient.
Schwab, Kellogg J.; Neill, Frederick H.; Fankhauser, Rebecca L.; Daniels, Nicholas A.; Monroe, Stephan S.; Bergmire-Sweat, David A.; Estes, Mary K.; Atmar, Robert L.
2000-01-01
“Norwalk-like viruses” (NLVs) and hepatitis A virus (HAV) are the most common causes of virus-mediated food-borne illness. Epidemiological investigations of outbreaks associated with these viruses have been hindered by the lack of available methods for the detection of NLVs and HAV in foodstuffs. Although reverse transcription (RT)-PCR methods have been useful in detecting NLVs and HAV in bivalve mollusks implicated in outbreaks, to date such methods have not been available for other foods. To address this need, we developed a method to detect NLVs and HAV recovered from food samples. The method involves washing of food samples with a guanidinium-phenol-based reagent, extraction with chloroform, and precipitation in isopropanol. Recovered viral RNA is amplified with HAV- or NLV-specific primers in RT-PCRs, using a viral RNA internal standard control to identify potential sample inhibition. By this method, 10 to 100 PCR units (estimated to be equivalent to 102 to 103 viral genome copies) of HAV and Norwalk virus seeded onto ham, turkey, and roast beef were detected. The method was applied to food samples implicated in an NLV-associated outbreak at a university cafeteria. Sliced deli ham was positive for a genogroup II NLV as determined by using both polymerase- and capsid-specific primers and probes. Sequence analysis of the PCR-amplified capsid region of the genome indicated that the sequence was identical to the sequence from virus detected in the stools of ill students. The developed method is rapid, simple, and efficient. PMID:10618226
Follow-Up of Norovirus Contamination in an Oyster Production Area Linked to Repeated Outbreaks.
Le Mennec, Cécile; Parnaudeau, Sylvain; Rumebe, Myriam; Le Saux, Jean-Claude; Piquet, Jean-Côme; Le Guyader, S Françoise
2017-03-01
A production area repeatedly implicated in oyster-related gastroenteritis in France was studied for several months over 2 years. Outbreaks and field samples were analyzed by undertaking triplicate extractions, followed by norovirus (NoV) detection using triplicate wells for genomic amplification. This approach allowed us to demonstrate that some variabilities can be observed for samples with a low level of contamination, but most samples analyzed gave reproducible results. At the first outbreak, implicated oysters were collected at the beginning of the contamination event, which was reflected by the higher NoV levels during the first month of the study. During the second year, NoV concentrations in samples implicated in outbreaks and collected from the production area were similar, confirming the failure of the shellfish depuration process. Contamination was detected mainly during winter-spring months, and a high prevalence of NoV GI contamination was observed. A half-life of 18 days was calculated from NoV concentrations detected in oysters during this study, showing a very slow decrease of the contamination in the production area. Preventing the contamination of coastal waters should be a priority.
Efficient detection of contagious outbreaks in massive metropolitan encounter networks
Sun, Lijun; Axhausen, Kay W.; Lee, Der-Horng; Cebrian, Manuel
2014-01-01
Physical contact remains difficult to trace in large metropolitan networks, though it is a key vehicle for the transmission of contagious outbreaks. Co-presence encounters during daily transit use provide us with a city-scale time-resolved physical contact network, consisting of 1 billion contacts among 3 million transit users. Here, we study the advantage that knowledge of such co-presence structures may provide for early detection of contagious outbreaks. We first examine the “friend sensor” scheme - a simple, but universal strategy requiring only local information - and demonstrate that it provides significant early detection of simulated outbreaks. Taking advantage of the full network structure, we then identify advanced “global sensor sets”, obtaining substantial early warning times savings over the friends sensor scheme. Individuals with highest number of encounters are the most efficient sensors, with performance comparable to individuals with the highest travel frequency, exploratory behavior and structural centrality. An efficiency balance emerges when testing the dependency on sensor size and evaluating sensor reliability; we find that substantial and reliable lead-time could be attained by monitoring only 0.01% of the population with the highest degree. PMID:24903017
Pseudo-outbreak of Actinomyces graevenitzii associated with bronchoscopy.
Peaper, David R; Havill, Nancy L; Aniskiewicz, Michael; Callan, Deborah; Pop, Olivia; Towle, Dana; Boyce, John M
2015-01-01
Outbreaks and pseudo-outbreaks of infection related to bronchoscopy typically involve Gram-negative bacteria, Mycobacterium species or Legionella species. We report an unusual bronchoscopy-related pseudo-outbreak due to Actinomyces graevenitzii. Extensive epidemiological and microbiological investigation failed to identify a common source. Strain typing revealed that the cluster was comprised of heterogeneous strains of A. graevenitzii. A change in laboratory procedures for Actinomyces cultures was coincident with the emergence of the pseudo-outbreak, and we determined that A. graevenitzii isolates more readily adopted a white, dry, molar tooth appearance on anaerobic colistin nalidixic acid (CNA) agar which likely facilitated its detection and identification in bronchoscopic specimens. This unusual pseudo-outbreak was related to frequent requests of bronchoscopists for Actinomyces cultures combined with a change in microbiology laboratory practices. Copyright © 2015, American Society for Microbiology. All Rights Reserved.
Guzman-Herrador, Bernardo R; Panning, Marcus; Stene-Johansen, Kathrine; Borgen, Katrine; Einöder-Moreno, Margot; Huzly, Daniela; Jensvoll, Laila; Lange, Heidi; Maassen, Sigrid; Myking, Solveig; Myrmel, Mette; Neumann-Haefelin, Christoph; Nygård, Karin; Wenzel, Jürgen J; Øye, Ann Kristin; Vold, Line
2015-11-01
In March 2014, after an increase of notifications of domestically acquired hepatitis A virus infections, an outbreak investigation was launched in Norway. Sequenced-based typing results showed that these cases were associated with a strain that was identical to one causing an ongoing multinational outbreak in Europe linked to frozen mixed berries. Thirty-three confirmed cases with the outbreak strain were notified in Norway from November 2013 to June 2014. Epidemiological evidence and trace-back investigations linked the outbreak to the consumption of a berry mix cake. Identification of the hepatitis A virus outbreak strain in berries from one of the implicated cakes confirmed the cake to be the source. Subsequently, a cluster in Germany linked to the cake was also identified.
Delays in Global Disease Outbreak Responses: Lessons from H1N1, Ebola, and Zika
Silverberg, Sarah L.
2018-01-01
In global disease outbreaks, there are significant time delays between the source of an outbreak and collective action. Some delay is necessary, but recent delays have been extended by insufficient surveillance capacity and time-consuming efforts to mobilize action. Three public health emergencies of international concern (PHEICs)—H1N1, Ebola, and Zika—allow us to identify and compare sources of delays and consider seven hypotheses about what influences the length of delays. These hypotheses can then motivate further research that empirically tests them. The three PHEICs suggest that deferred global mobilization is a greater source of delay than is poor surveillance capacity. These case study outbreaks support hypotheses that we see quicker responses for novel diseases when outbreaks do not coincide with holidays and when US citizens are infected. They do not support hypotheses that we see quicker responses for more severe outbreaks or those that threaten larger numbers of people. Better understanding the reason for delays can help target policy interventions and identify the kind of global institutional changes needed to reduce the spread and severity of future PHEICs. PMID:29345996
TESTING METHODS FOR DETECTION OF CRYPTOSPORIDIUM SPP. IN WATER SAMPLES
A large waterborne outbreak of cryptosporidiosis in Milwaukee, Wisconsin, U.S.A. in 1993 prompted a search for ways to prevent large scale waterborne outbreaks of protozoan parasitoses. Two principle strategies have emerged: risk assessment leading to appropriate treatment and ...
CDC Support for Global Public Health Emergency Management.
Brencic, Daniel J; Pinto, Meredith; Gill, Adrienne; Kinzer, Michael H; Hernandez, Luis; Pasi, Omer G
2017-12-01
Recent pandemics and rapidly spreading outbreaks of infectious diseases have illustrated the interconnectedness of the world and the importance of improving the international community's ability to effectively respond. The Centers for Disease Control and Prevention (CDC), building on a strong foundation of lessons learned through previous emergencies, international recognition, and human and technical expertise, has aspired to support nations around the world to strengthen their public health emergency management (PHEM) capacity. PHEM principles streamline coordination and collaboration in responding to infectious disease outbreaks, which align with the core capacities outlined in the International Health Regulations 2005. CDC supports PHEM by providing in-country technical assistance, aiding the development of plans and procedures, and providing fellowship opportunities for public health emergency managers. To this end, CDC partners with US agencies, international partners, and multilateral organizations to support nations around the world to reduce illness and death from outbreaks of infectious diseases.
Liu, Yao; Shi, Xiaolu; Li, Yinghui; Chen, Qiongcheng; Jiang, Min; Li, Wanli; Qiu, Yaqun; Lin, Yiman; Jiang, Yixiang; Kan, Biao; Sun, Qun; Hu, Qinghua
2016-01-29
Salmonella enterica subsp. enterica serovar Enteritidis (S. Enteritidis) is one of the most prevalent Salmonella serotypes that cause gastroenteritis worldwide and the most prevalent serotype causing Salmonella infections in China. A rapid molecular typing method with high throughput and good epidemiological discrimination is urgently needed for detecting the outbreaks and finding the source for effective control of S. Enteritidis infections. In this study, 194 strains which included 47 from six outbreaks that were well-characterized epidemiologically were analyzed with pulse field gel electrophoresis (PFGE) and multilocus variable number tandem repeat analysis (MLVA). Seven VNTR loci published by the US Center for Disease Control and Prevention (CDC) were used to evaluate and develop MLVA scheme for S. Enteritidis molecular subtyping by comparing with PFGE, and then MLVA was applied to the suspected outbreaks detection. All S. Enteritidis isolates were analyzed with MLVA to establish a MLVA database in Shenzhen, Guangdong province, China to facilitate the detection of S. Enteritidis infection clusters. There were 33 MLVA types and 29 PFGE patterns among 147 sporadic isolates. These two measures had Simpson indices of 0.7701 and 0.8043, respectively, which did not differ significantly. Epidemiological concordance was evaluated by typing 47 isolates from six epidemiologically well-characterized outbreaks and it did not differ for PFGE and MLVA. We applied the well established MLVA method to detect two S. Enteritidis foodborne outbreaks and find their sources successfully in 2014. A MLVA database of 491 S. Enteritidis strains isolated from 2004 to 2014 was established for the surveillance of clusters in the future. MLVA typing of S. Enteritidis would be an effective tool for early warning and epidemiological surveillance of S. Enteritidis infections.
Genetic characterization of measles virus in the Philippines, 2008-2011.
Centeno, Rex; Fuji, Naoko; Okamoto, Michiko; Dapat, Clyde; Saito, Mariko; Tandoc, Amado; Lupisan, Socorro; Oshitani, Hitoshi
2015-06-03
Large outbreaks of measles occurred in the Philippines in 2010 and 2011. Genetic analysis was performed to identify the genotype of measles virus (MeV) that was responsible for the large outbreaks. A total of 114 representative MeVs that were detected in the Philippines from 2008 to 2011 were analyzed by sequencing the C-terminal region of nucleocapsid (N) gene and partial hemagglutinin (H) gene and by inferring the phylogenetic trees. Genetic analysis showed that genotype D9 was the predominant circulating strain during the 4-year study period. Genotype D9 was detected in 23 samples (92%) by N gene sequencing and 93 samples (94%) by H gene analysis. Sporadic cases of genotype G3 MeV were identified in 2 samples (8%) by N gene sequencing and 6 samples (6%) by H gene analysis. Genotype G3 MeV was detected mainly in Panay Island in 2009 and 2010. Molecular clock analysis of N gene showed that the recent genotype D9 viruses that caused the big outbreaks in 2010 and 2011 diverged from a common ancestor in 2005 in one of the neighboring Southeast Asian countries, where D9 was endemic. These big outbreaks of measles resulted in a spillover and were associated with genotype D9 MeV importation to Japan and the USA. Genotype D9 MeV became endemic and caused two big outbreaks in the Philippines in 2010 and 2011. Genotype G3 MeV was detected sporadically with limited geographic distribution. This study highlights the importance of genetic analysis not only in helping with the assessment of measles elimination program in the country but also in elucidating the transmission dynamics of measles virus.
Mykhalovskiy, Eric; Weir, Lorna
2006-01-01
The recent SARS epidemic has renewed widespread concerns about the global transmission of infectious diseases. In this commentary, we explore novel approaches to global infectious disease surveillance through a focus on an important Canadian contribution to the area--the Global Public Health Intelligence Network (GPHIN). GPHIN is a cutting-edge initiative that draws on the capacity of the Internet and newly available 24/7 global news coverage of health events to create a unique form of early warning outbreak detection. This commentary outlines the operation and development of GPHIN and compares it to ProMED-mail, another Internet-based approach to global health surveillance. We argue that GPHIN has created an important shift in the relationship of public health and news information. By exiting the pyramid of official reporting, GPHIN has created a new monitoring technique that has disrupted national boundaries of outbreak notification, while creating new possibilities for global outbreak response. By incorporating news within the emerging apparatus of global infectious disease surveillance, GPHIN has effectively responded to the global media's challenge to official country reporting of outbreak and enhanced the effectiveness and credibility of international public health.
Suijkerbuijk, Anita W M; Bouwknegt, Martijn; Mangen, Marie-Josee J; de Wit, G Ardine; van Pelt, Wilfrid; Bijkerk, Paul; Friesema, Ingrid H M
2017-04-01
In 2012, the Netherlands experienced the most extensive food-related outbreak of Salmonella ever recorded. It was caused by smoked salmon contaminated with Salmonella Thompson during processing. In total, 1149 cases of salmonellosis were laboratory confirmed and reported to RIVM. Twenty percent of cases was hospitalised and four cases were reported to be fatal. The purpose of this study was to estimate total costs of the Salmonella Thompson outbreak. Data from a case-control study were used to estimate the cost-of-illness of reported cases (i.e. healthcare costs, patient costs and production losses). Outbreak control costs were estimated based on interviews with staff from health authorities. Using the Dutch foodborne disease burden and cost-of-illness model, we estimated the number of underestimated cases and the associated cost-of-illness. The estimated number of cases, including reported and underestimated cases was 21 123. Adjusted for underestimation, the total cost-of-illness would be €6.8 million (95% CI €2.5-€16.7 million) with productivity losses being the main cost driver. Adding outbreak control costs, the total outbreak costs are estimated at €7.5 million. In the Netherlands, measures are taken to reduce salmonella concentrations in food, but detection of contamination during food processing remains difficult. As shown, Salmonella outbreaks have the potential for a relatively high disease and economic burden for society. Early warning and close cooperation between the industry, health authorities and laboratories is essential for rapid detection, control of outbreaks, and to reduce disease and economic burden. © The Author 2016. Published by Oxford University Press on behalf of the European Public Health Association. All rights reserved.
Mahida, N; Prescott, K; Yates, C; Spencer, F; Weston, V; Boswell, T
2018-03-29
Outbreaks of group A streptococcus (GAS) infections may occur in healthcare settings. Transmission to patients is sometimes linked to colonized healthcare workers (HCWs) and/or a contaminated environment. To describe the investigation and control of an outbreak of healthcare-associated GAS on an elderly care medical ward, over six months. Four patients developed septicaemia due to GAS infection without a clinically obvious site of infection. The outbreak team undertook an investigation involving a retrospective review of GAS cases, prospective case finding, HCW screening and environmental sampling using both swabs and settle plates. Immediate control measures included source isolation and additional cleaning of the ward environment with a chlorine disinfectant and hydrogen peroxide. Prospective patient screening identified one additional patient with throat GAS carriage. Settle plate positivity for GAS was strongly associated with the presence of one individual HCW on the ward, who was subsequently found to have GAS perineal carriage. Contamination of a fabric-upholstered chair in an office adjacent to the ward, used by the HCW, was also detected. In total, three asymptomatic HCWs had throat GAS carriage and one HCW had both perineal and throat carriage. All isolates were typed as emm 28. This is the first outbreak report demonstrating the use of settle plates in a GAS outbreak investigation on a medical ward, to identify the likely source of the outbreak. Based on this report we recommend that both throat and perineal sites should be sampled if HCW screening is undertaken during an outbreak of GAS. Fabric, soft furnishings should be excluded from clinical areas as well as any adjacent offices because pathogenic bacteria such as GAS may contaminate this environment. Copyright © 2018 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.
The Methanol Poisoning Outbreaks in Libya 2013 and Kenya 2014
Rostrup, Morten; Edwards, Jeffrey K.; Abukalish, Mohamed; Ezzabi, Masoud; Some, David; Ritter, Helga; Menge, Tom; Abdelrahman, Ahmed; Rootwelt, Rebecca; Janssens, Bart; Lind, Kyrre; Paasma, Raido; Hovda, Knut Erik
2016-01-01
Background Outbreaks of methanol poisoning occur frequently on a global basis, affecting poor and vulnerable populations. Knowledge regarding methanol is limited, likely many cases and even outbreaks go unnoticed, with patients dying unnecessarily. We describe findings from the first three large outbreaks of methanol poisoning where Médecins Sans Frontières (MSF) responded, and evaluate the benefits of a possible future collaboration between local health authorities, a Non-Governmental Organisation and international expertise. Methods Retrospective study of three major methanol outbreaks in Libya (2013) and Kenya (May and July 2014). Data were collected from MSF field personnel, local health personnel, hospital files, and media reports. Findings In Tripoli, Libya, over 1,000 patients were poisoned with a reported case fatality rate of 10% (101/1,066). In Kenya, two outbreaks resulted in approximately 341 and 126 patients, with case fatality rates of 29% (100/341) and 21% (26/126), respectively. MSF launched an emergency team with international experts, medications and equipment, however, the outbreaks were resolving by the time of arrival. Interpretation Recognition of an outbreak of methanol poisoning and diagnosis seem to be the most challenging tasks, with significant delay from time of first presentations to public health warnings being issued. In spite of the rapid response from an emergency team, the outbreaks were nearly concluded by the time of arrival. A major impact on the outcome was not seen, but large educational trainings were conducted to increase awareness and knowledge about methanol poisoning. Based on this training, MSF was able to send a local emergency team during the second outbreak, supporting that such an approach could improve outcomes. Basic training, simplified treatment protocols, point-of-care diagnostic tools, and early support when needed, are likely the most important components to impact the consequences of methanol poisoning outbreaks in these challenging contexts. PMID:27030969
Dale, Katie; Kirk, Martyn; Sinclair, Martha; Hall, Robert; Leder, Karin
2010-10-01
To examine the frequency and circumstances of reported waterborne outbreaks of gastroenteritis in Australia. Examination of data reported to OzFoodNet between 2001 and 2007. During these seven years, 6,515 gastroenteritis outbreaks were reported to OzFoodNet, most of which were classified as being transmitted person-to-person or from an unknown source. Fifty-four (0.83%) outbreaks were classified as either 'waterborne' or 'suspected waterborne', of which 78% (42/54) were attributed to recreational water and 19% (10/54) to drinking water. Of the drinking water outbreaks, implicated pathogens were found on all but one occasion and included Salmonella sp. (five outbreaks), Campylobacter jejuni (three outbreaks) and Giardia (one outbreak). There have been few waterborne outbreaks detected in Australia, and most of those reported have been associated with recreational exposure. However, there are difficulties in identifying and categorising gastroenteritis outbreaks, as well as in obtaining microbiological and epidemiological evidence, which can result in misclassification or underestimation of water-associated events. Gastroenteritis surveillance data show that, among reported water-associated gastroenteritis outbreaks in Australia, recreational exposure is currently more common than a drinking water source. However, ongoing surveillance for waterborne outbreaks is important, especially as drought conditions may necessitate replacement of conventional drinking water supplies with alternative water sources, which could incur potential for new health risks. © 2010 The Authors. Journal Compilation © 2010 Public Health Association of Australia.
Qiu, Shaofu; Li, Peng; Liu, Hongbo; Wang, Yong; Liu, Nan; Li, Chengyi; Li, Shenlong; Li, Ming; Jiang, Zhengjie; Sun, Huandong; Li, Ying; Xie, Jing; Yang, Chaojie; Wang, Jian; Li, Hao; Yi, Shengjie; Wu, Zhihao; Jia, Leili; Wang, Ligui; Hao, Rongzhang; Sun, Yansong; Huang, Liuyu; Ma, Hui; Yuan, Zhengquan; Song, Hongbin
2015-01-01
From December 2012 to February 2013, two outbreaks of acute respiratory disease caused by HAdV-7 were reported in China. We investigated possible transmission links between these two seemingly unrelated outbreaks by integration of epidemiological and whole-genome sequencing (WGS) data. WGS analyses showed that the HAdV-7 isolates from the two outbreaks were genetically indistinguishable; however, a 12 bp deletion in the virus-associated RNA gene distinguished the outbreak isolates from other HAdV-7 isolates. Outbreak HAdV-7 isolates demonstrated increased viral replication compared to non-outbreak associated HAdV-7 isolate. Epidemiological data supported that the first outbreak was caused by introduction of the novel HAdV-7 virus by an infected recruit upon arrival at the training base. Nosocomial transmission by close contacts was the most likely source leading to onset of the second HAdV-7 outbreak, establishing the apparent transmission link between the outbreaks. Our findings imply that in-hospital contact investigations should be encouraged to reduce or interrupt further spread of infectious agents when treating outbreak cases, and WGS can provide useful information guiding infection-control interventions. PMID:26338697
Epidemiology and estimated costs of a large waterborne outbreak of norovirus infection in Sweden.
Larsson, C; Andersson, Y; Allestam, G; Lindqvist, A; Nenonen, N; Bergstedt, O
2014-03-01
A large outbreak of norovirus (NoV) gastroenteritis caused by contaminated municipal drinking water occurred in Lilla Edet, Sweden, 2008. Epidemiological investigations performed using a questionnaire survey showed an association between consumption of municipal drinking water and illness (odds ratio 4·73, 95% confidence interval 3·53-6·32), and a strong correlation between the risk of being sick and the number of glasses of municipal water consumed. Diverse NoV strains were detected in stool samples from patients, NoV genotype I strains predominating. Although NoVs were not detected in water samples, coliphages were identified as a marker of viral contamination. About 2400 (18·5%) of the 13,000 inhabitants in Lilla Edet became ill. Costs associated with the outbreak were collected via a questionnaire survey given to organizations and municipalities involved in or affected by the outbreak. Total costs including sick leave, were estimated to be ∼8,700,000 Swedish kronor (∼€0·87 million).
Outbreak of viral gastroenteritis due to drinking water contaminated by Norwalk-like viruses.
Kukkula, M; Maunula, L; Silvennoinen, E; von Bonsdorff, C H
1999-12-01
Heinävesi, a Finnish municipality with a population of 4860 inhabitants, had an outbreak of gastroenteritis in March 1998. On the basis of an epidemiologic survey, an estimated 1700-3000 cases of acute gastroenteritis occurred during the outbreak. Municipal water consumption was found to be associated with illness (risk ratio [RR]=3.5, 95% confidence interval, 3.11>RR>3.96). Norwalk-like virus (NLV) genogroup II (GGII) was identified in untreated water, treated water, and 4 tap water samples by use of reverse transcription-polymerase chain reaction. This was the first time NLVs had been detected in municipal tap water. Fifteen of 27 patient stool samples had NLV GGII, with an identical amplification product to that found in the water samples, indicating that the outbreak was caused by this virus. In some patients, NLV genogroup I was also encountered. This virus, however, could not be detected in the water samples. Inadequate chlorination contributed to the survival of the virus in the water.
Highly Pathogenic Avian Influenza Virus (H5N1) in Frozen Duck Carcasses, Germany, 2007
Harder, Timm C.; Teuffert, Jürgen; Starick, Elke; Gethmann, Jörn; Grund, Christian; Fereidouni, Sasan; Durban, Markus; Bogner, Karl-Heinz; Neubauer-Juric, Antonie; Repper, Reinhard; Hlinak, Andreas; Engelhardt, Andreas; Nöckler, Axel; Smietanka, Krzysztof; Minta, Zenon; Kramer, Matthias; Globig, Anja; Mettenleiter, Thomas C.; Conraths, Franz J.
2009-01-01
We conducted phylogenetic and epidemiologic analyses to determine sources of outbreaks of highly pathogenic avian influenza virus (HPAIV), subtype H5N1, in poultry holdings in 2007 in Germany, and a suspected incursion of HPAIV into the food chain through contaminated deep-frozen duck carcasses. In summer 2007, HPAIV (H5N1) outbreaks in 3 poultry holdings in Germany were temporally, spatially, and phylogenetically linked to outbreaks in wild aquatic birds. Detection of HPAIV (H5N1) in frozen duck carcass samples of retained slaughter batches of 1 farm indicated that silent infection had occurred for some time before the incidental detection. Phylogenetic analysis established a direct epidemiologic link between HPAIV isolated from duck meat and strains isolated from 3 further outbreaks in December 2007 in backyard chickens that had access to uncooked offal from commercial deep-frozen duck carcasses. Measures that will prevent such undetected introduction of HPAIV (H5N1) into the food chain are urgently required. PMID:19193272
Durr, Peter A.; Graham, Kerryne; van Klinken, Rieks D.
2017-01-01
The possibility that outbreaks of bluetongue (BT) and African horse sickness (AHS) might occur via long-distance wind dispersion (LDWD) of their insect vector (Culicoides spp.) was proposed by R. F. Sellers in a series of papers published between 1977 and 1991. These investigated the role of LDWD by means of visual examination of the wind direction of synoptic weather charts. Based on the hypothesis that simple wind direction analysis, which does not allow for wind speed, might have led to spurious conclusions, we reanalyzed six of the outbreak scenarios described in Sellers’ papers. For this reanalysis, we used a custom-built Big Data application (“TAPPAS”) which couples a user-friendly web-interface with an established atmospheric dispersal model (“HYSPLIT”), thus enabling more sophisticated modeling than was possible when Sellers undertook his analyzes. For the two AHS outbreaks, there was strong support from our reanalysis of the role of LDWD for that in Spain (1966), and to a lesser degree, for the outbreak in Cyprus (1960). However, for the BT outbreaks, the reassessments were more complex, and for one of these (western Turkey, 1977) we could discount LDWD as the means of direct introduction of the virus. By contrast, while the outbreak in Cyprus (1977) showed LDWD was a possible means of introduction, there is an apparent inconsistency in that the outbreaks were localized while the dispersion events covered much of the island. For Portugal (1956), LDWD from Morocco on the dates suggested by Sellers is very unlikely to have been the pathway for introduction, and for the detection of serotype 2 in Florida (1982), LDWD from Cuba would require an assumption of a lengthy survival time of the midges in the air column. Except for western Turkey, the BT reanalyses show the limitation of LDWD modeling when used by itself, and indicates the need to integrate susceptible host population distribution (and other covariate) data into the modeling process. A further refinement, which will become increasingly important to assess LDWD, will be the use of virus and vector genome sequence data collected from potential source and the incursion sites. PMID:28775987
Most Common Foodborne Pathogens and Mycotoxins on Fresh Produce: A Review of Recent Outbreaks.
Yeni, F; Yavaş, S; Alpas, H; Soyer, Y
2016-07-03
Every year millions of people are affected and thousands of them die due to infections and intoxication as a result of foodborne outbreaks, which also cause billions of dollars' worth of damage, public health problems, and agricultural product loss. A considerable portion of these outbreaks is related to fresh produce and caused by foodborne pathogens on fresh produce and mycotoxins. Escherichia coli O104:H4 outbreak, occurred in Germany in 2011, has attracted a great attention on foodborne outbreaks caused by contaminated fresh produce, and especially the vulnerability and gaps in the early warning and notification networks in the surveillance systems in all around the world. In the frame of this paper, we reviewed the most common foodborne pathogens on fresh produce, traceback investigations of the outbreaks caused by these pathogens, and lastly international early warning and notification systems, including PulseNet International and Rapid Alert System for Food and Feed, aiming to detect foodborne outbreaks.
Jalava, Katri; Rintala, Hanna; Ollgren, Jukka; Maunula, Leena; Gomez-Alvarez, Vicente; Revez, Joana; Palander, Marja; Antikainen, Jenni; Kauppinen, Ari; Räsänen, Pia; Siponen, Sallamaari; Nyholm, Outi; Kyyhkynen, Aino; Hakkarainen, Sirpa; Merentie, Juhani; Pärnänen, Martti; Loginov, Raisa; Ryu, Hodon; Kuusi, Markku; Siitonen, Anja; Miettinen, Ilkka; Santo Domingo, Jorge W; Hänninen, Marja-Liisa; Pitkänen, Tarja
2014-01-01
Failures in the drinking water distribution system cause gastrointestinal outbreaks with multiple pathogens. A water distribution pipe breakage caused a community-wide waterborne outbreak in Vuorela, Finland, July 2012. We investigated this outbreak with advanced epidemiological and microbiological methods. A total of 473/2931 inhabitants (16%) responded to a web-based questionnaire. Water and patient samples were subjected to analysis of multiple microbial targets, molecular typing and microbial community analysis. Spatial analysis on the water distribution network was done and we applied a spatial logistic regression model. The course of the illness was mild. Drinking untreated tap water from the defined outbreak area was significantly associated with illness (RR 5.6, 95% CI 1.9-16.4) increasing in a dose response manner. The closer a person lived to the water distribution breakage point, the higher the risk of becoming ill. Sapovirus, enterovirus, single Campylobacter jejuni and EHEC O157:H7 findings as well as virulence genes for EPEC, EAEC and EHEC pathogroups were detected by molecular or culture methods from the faecal samples of the patients. EPEC, EAEC and EHEC virulence genes and faecal indicator bacteria were also detected in water samples. Microbial community sequencing of contaminated tap water revealed abundance of Arcobacter species. The polyphasic approach improved the understanding of the source of the infections, and aided to define the extent and magnitude of this outbreak.
Denayer, Sarah; Nia, Yacine; Botteldoorn, Nadine
2017-01-01
Staphylococcus aureus is an important aetiological agent of food intoxications in the European Union as it can cause gastro-enteritis through the production of various staphylococcal enterotoxins (SEs) in foods. Reported enterotoxin dose levels causing food-borne illness are scarce and varying. Three food poisoning outbreaks due to enterotoxin-producing S. aureus strains which occurred in 2013 in Belgium are described. The outbreaks occurred in an elderly home, at a barbecue event and in a kindergarten and involved 28, 18, and six cases, respectively. Various food leftovers contained coagulase positive staphylococci (CPS). Low levels of staphylococcal enterotoxins ranging between 0.015 ng/g and 0.019 ng/g for enterotoxin A (SEA), and corresponding to 0.132 ng/g for SEC were quantified in the food leftovers for two of the reported outbreaks. Molecular typing of human and food isolates using pulsed-field gel electrophoresis (PFGE) and enterotoxin gene typing, confirmed the link between patients and the suspected foodstuffs. This also demonstrated the high diversity of CPS isolates both in the cases and in healthy persons carrying enterotoxin genes encoding emetic SEs for which no detection methods currently exist. For one outbreak, the investigation pointed out to the food handler who transmitted the outbreak strain to the food. Tools to improve staphylococcal food poisoning (SFP) investigations are presented. PMID:29261162
Nikolay, Birgit; Salje, Henrik; Sturm-Ramirez, Katharine; Azziz-Baumgartner, Eduardo; Homaira, Nusrat; Iuliano, A. Danielle; Paul, Repon C.; Hossain, M. Jahangir; Cauchemez, Simon; Gurley, Emily S.
2017-01-01
Background The International Health Regulations outline core requirements to ensure the detection of public health threats of international concern. Assessing the capacity of surveillance systems to detect these threats is crucial for evaluating a country’s ability to meet these requirements. Methods and Findings We propose a framework to evaluate the sensitivity and representativeness of hospital-based surveillance and apply it to severe neurological infectious diseases and fatal respiratory infectious diseases in Bangladesh. We identified cases in selected communities within surveillance hospital catchment areas using key informant and house-to-house surveys and ascertained where cases had sought care. We estimated the probability of surveillance detecting different sized outbreaks by distance from the surveillance hospital and compared characteristics of cases identified in the community and cases attending surveillance hospitals. We estimated that surveillance detected 26% (95% CI 18%–33%) of severe neurological disease cases and 18% (95% CI 16%–21%) of fatal respiratory disease cases residing at 10 km distance from a surveillance hospital. Detection probabilities decreased markedly with distance. The probability of detecting small outbreaks (three cases) dropped below 50% at distances greater than 26 km for severe neurological disease and at distances greater than 7 km for fatal respiratory disease. Characteristics of cases attending surveillance hospitals were largely representative of all cases; however, neurological disease cases aged <5 y or from the lowest socioeconomic group and fatal respiratory disease cases aged ≥60 y were underrepresented. Our estimates of outbreak detection rely on suspected cases that attend a surveillance hospital receiving laboratory confirmation of disease and being reported to the surveillance system. The extent to which this occurs will depend on disease characteristics (e.g., severity and symptom specificity) and surveillance resources. Conclusion We present a new approach to evaluating the sensitivity and representativeness of hospital-based surveillance, making it possible to predict its ability to detect emerging threats. PMID:28095468
Molecular Characterization of Two Major Dengue Outbreaks in Costa Rica.
Soto-Garita, Claudio; Somogyi, Teresita; Vicente-Santos, Amanda; Corrales-Aguilar, Eugenia
2016-07-06
Dengue virus (DENV) (Flavivirus, Flaviviridae) is a reemerging arthropod-borne virus with a worldwide circulation, transmitted mainly by Aedes aegypti and Aedes albopictus mosquitoes. Since the first detection of its main transmitting vector in 1992 and the invasion of DENV-1 in 1993, Costa Rica has faced dengue outbreaks yearly. In 2007 and 2013, Costa Rica experienced two of the largest outbreaks in terms of total and severe cases. To provide genetic information about the etiologic agents producing these outbreaks, we conducted phylogenetic analysis of viruses isolated from human samples. A total of 23 DENV-1 and DENV-2 sequences were characterized. These analyses signaled that DENV-1 genotype V and DENV-2 American/Asian genotype were circulating in those outbreaks. Our results suggest that the 2007 and 2013 outbreak viral strains of DENV-1 and DENV-2 originated from nearby countries and underwent in situ microevolution. © The American Society of Tropical Medicine and Hygiene.
Giardiasis Outbreak Associated with Asymptomatic Food Handlers in New York State, 2015.
Figgatt, Mary; Mergen, Kimberly; Kimelstein, Deborah; Mahoney, Danielle M; Newman, Alexandra; Nicholas, David; Ricupero, Kristen; Cafiero, Theresa; Corry, Daniel; Ade, Julius; Kurpiel, Philip; Madison-Antenucci, Susan; Anand, Madhu
2017-04-12
Giardia duodenalis is a protozoan that causes a gastrointestinal illness called giardiasis. Giardiasis outbreaks in the United States are most commonly associated with waterborne transmission and are less commonly associated with food, person-to-person, and zoonotic transmission. During June to September 2015, an outbreak of 20 giardiasis cases occurred and were epidemiologically linked to a local grocery store chain on Long Island, New York. Further investigation revealed three asymptomatic food handlers were infected with G. duodenalis , and one food handler and one case were coinfected with Cryptosporidium spp. Although G. duodenalis was not detected in food samples, Cryptosporidium was identified in samples of spinach dip and potato salad. The G. duodenalis assemblage and subtype from one of the food handlers matched two outbreak cases for which genotyping could be performed. This outbreak highlights the potential role of asymptomatically infected food handlers in giardiasis outbreaks.
Lund, Magnus; Raundrup, Katrine; Westergaard-Nielsen, Andreas; López-Blanco, Efrén; Nymand, Josephine; Aastrup, Peter
2017-02-01
Insect outbreaks can have important consequences for tundra ecosystems. In this study, we synthesise available information on outbreaks of larvae of the noctuid moth Eurois occulta in Greenland. Based on an extensive dataset from a monitoring programme in Kobbefjord, West Greenland, we demonstrate effects of a larval outbreak in 2011 on vegetation productivity and CO 2 exchange. We estimate a decreased carbon (C) sink strength in the order of 118-143 g C m -2 , corresponding to 1210-1470 tonnes C at the Kobbefjord catchment scale. The decreased C sink was, however, counteracted the following years by increased primary production, probably facilitated by the larval outbreak increasing nutrient turnover rates. Furthermore, we demonstrate for the first time in tundra ecosystems, the potential for using remote sensing to detect and map insect outbreak events.
Molecular Characterization of Two Major Dengue Outbreaks in Costa Rica
Soto-Garita, Claudio; Somogyi, Teresita; Vicente-Santos, Amanda; Corrales-Aguilar, Eugenia
2016-01-01
Dengue virus (DENV) (Flavivirus, Flaviviridae) is a reemerging arthropod-borne virus with a worldwide circulation, transmitted mainly by Aedes aegypti and Aedes albopictus mosquitoes. Since the first detection of its main transmitting vector in 1992 and the invasion of DENV-1 in 1993, Costa Rica has faced dengue outbreaks yearly. In 2007 and 2013, Costa Rica experienced two of the largest outbreaks in terms of total and severe cases. To provide genetic information about the etiologic agents producing these outbreaks, we conducted phylogenetic analysis of viruses isolated from human samples. A total of 23 DENV-1 and DENV-2 sequences were characterized. These analyses signaled that DENV-1 genotype V and DENV-2 American/Asian genotype were circulating in those outbreaks. Our results suggest that the 2007 and 2013 outbreak viral strains of DENV-1 and DENV-2 originated from nearby countries and underwent in situ microevolution. PMID:27139442
Perrin, Jean-Baptiste; Durand, Benoît; Gay, Emilie; Ducrot, Christian; Hendrikx, Pascal; Calavas, Didier; Hénaux, Viviane
2015-01-01
We performed a simulation study to evaluate the performances of an anomaly detection algorithm considered in the frame of an automated surveillance system of cattle mortality. The method consisted in a combination of temporal regression and spatial cluster detection which allows identifying, for a given week, clusters of spatial units showing an excess of deaths in comparison with their own historical fluctuations. First, we simulated 1,000 outbreaks of a disease causing extra deaths in the French cattle population (about 200,000 herds and 20 million cattle) according to a model mimicking the spreading patterns of an infectious disease and injected these disease-related extra deaths in an authentic mortality dataset, spanning from January 2005 to January 2010. Second, we applied our algorithm on each of the 1,000 semi-synthetic datasets to identify clusters of spatial units showing an excess of deaths considering their own historical fluctuations. Third, we verified if the clusters identified by the algorithm did contain simulated extra deaths in order to evaluate the ability of the algorithm to identify unusual mortality clusters caused by an outbreak. Among the 1,000 simulations, the median duration of simulated outbreaks was 8 weeks, with a median number of 5,627 simulated deaths and 441 infected herds. Within the 12-week trial period, 73% of the simulated outbreaks were detected, with a median timeliness of 1 week, and a mean of 1.4 weeks. The proportion of outbreak weeks flagged by an alarm was 61% (i.e. sensitivity) whereas one in three alarms was a true alarm (i.e. positive predictive value). The performances of the detection algorithm were evaluated for alternative combination of epidemiologic parameters. The results of our study confirmed that in certain conditions automated algorithms could help identifying abnormal cattle mortality increases possibly related to unidentified health events.
Perrin, Jean-Baptiste; Durand, Benoît; Gay, Emilie; Ducrot, Christian; Hendrikx, Pascal; Calavas, Didier; Hénaux, Viviane
2015-01-01
We performed a simulation study to evaluate the performances of an anomaly detection algorithm considered in the frame of an automated surveillance system of cattle mortality. The method consisted in a combination of temporal regression and spatial cluster detection which allows identifying, for a given week, clusters of spatial units showing an excess of deaths in comparison with their own historical fluctuations. First, we simulated 1,000 outbreaks of a disease causing extra deaths in the French cattle population (about 200,000 herds and 20 million cattle) according to a model mimicking the spreading patterns of an infectious disease and injected these disease-related extra deaths in an authentic mortality dataset, spanning from January 2005 to January 2010. Second, we applied our algorithm on each of the 1,000 semi-synthetic datasets to identify clusters of spatial units showing an excess of deaths considering their own historical fluctuations. Third, we verified if the clusters identified by the algorithm did contain simulated extra deaths in order to evaluate the ability of the algorithm to identify unusual mortality clusters caused by an outbreak. Among the 1,000 simulations, the median duration of simulated outbreaks was 8 weeks, with a median number of 5,627 simulated deaths and 441 infected herds. Within the 12-week trial period, 73% of the simulated outbreaks were detected, with a median timeliness of 1 week, and a mean of 1.4 weeks. The proportion of outbreak weeks flagged by an alarm was 61% (i.e. sensitivity) whereas one in three alarms was a true alarm (i.e. positive predictive value). The performances of the detection algorithm were evaluated for alternative combination of epidemiologic parameters. The results of our study confirmed that in certain conditions automated algorithms could help identifying abnormal cattle mortality increases possibly related to unidentified health events. PMID:26536596
Minagawa, Hiroko; Yasui, Yoshihiro; Adachi, Hirokazu; Ito, Miyabi; Hirose, Emi; Nakamura, Noriko; Hata, Mami; Kobayashi, Shinichi; Yamashita, Teruo
2015-11-09
Japan was verified as having achieved measles elimination by the Measles Regional Verification Commission in the Western Pacific Region in March 2015. Verification of measles elimination implies the absence of continuous endemic transmission. After the last epidemic in 2007 with an estimated 18,000 cases, Japan introduced nationwide case-based measles surveillance in January 2008. Laboratory diagnosis for all suspected measles cases is essentially required by law, and virus detection tests are mostly performed by municipal public health institutes. Despite relatively high vaccination coverage and vigorous response to every case by the local health center staff, outbreak of measles is repeatedly observed in Aichi Prefecture, Japan. Measles virus N and H gene detection by nested double RT-PCR was performed with all specimens collected from suspected cases and transferred to our institute. Genotyping and further molecular epidemiological analyses were performed with the direct nucleotide sequence data of appropriate PCR products. Between 2010 and 2014, specimens from 389 patients suspected for measles were tested in our institute. Genotypes D9, D8, H1 and B3 were detected. Further molecular epidemiological analyses were helpful to establish links between patients, and sometimes useful to discriminate one outbreak from another. All virus-positive cases, including 49 cases involved in three outbreaks without any obvious epidemiological link with importation, were considered as import-related based on the nucleotide sequence information. Chain of transmission in the latest outbreak in 2014 terminated after the third generations, much earlier than the 2010-11 outbreak (6th generations). Since 2010, almost all measles cases reported in Aichi Prefecture are either import or import-related, based primarily on genotypes and nucleotide sequences of measles virus detected. In addition, genotyping and molecular epidemiological analyses are indispensable to prove the interruption of endemic transmission when the importations of measles are repeatedly observed. Copyright © 2015 Elsevier Ltd. All rights reserved.
Why has the Ebola outbreak in West Africa been so challenging to control?
Semalulu, T; Wong, G; Kobinger, G; Huston, P
2014-01-01
West Africa is in the midst of the largest Ebola outbreak ever; there have been over 1000 deaths and many new cases are reported each day. The World Health Organization (WHO) declared it an outbreak in March 2014 and on August 6, 2014 the WHO declared the outbreak a public health emergency of international concern. Based on the number of deaths and total number of cases reported to the WHO as of August 11, 2014, the current outbreak has an overall mortality rate of 55%. Outbreak control measures against Ebola virus disease are effective. Why then, has this outbreak been so challenging to control? Ebola is transmitted through bodily fluids and immediately attacks the immune system, then progressively attacks the major organs and the lining of blood vessels. Sierra Leone, Guinea and Liberia are small countries that have limited resources to respond to prolonged outbreaks, especially in rural areas. This has been made more challenging by the fact that health care workers are at risk of contracting Ebola virus disease. Treatment to date has been supportive, not curative and outbreak control strategies have been met with distrust due to fear and misinformation. However, important progress is being made. The international response to Ebola is gaining momentum, communication strategies have been developed to address the fear and mistrust, and promising treatments are under development, including a combination of three monoclonal antibodies that has been administered to two American Ebola infected health care workers. The National Microbiology Laboratory of the Public Health Agency of Canada (PHAC) has been supporting laboratory diagnostic efforts in West Africa and PHAC has been working with the provinces and territories and key stakeholders to ensure Canada is prepared for a potential Ebola importation. PMID:29769855
Why has the Ebola outbreak in West Africa been so challenging to control?
Semalulu, T; Wong, G; Kobinger, G; Huston, P
2014-08-14
West Africa is in the midst of the largest Ebola outbreak ever; there have been over 1000 deaths and many new cases are reported each day. The World Health Organization (WHO) declared it an outbreak in March 2014 and on August 6, 2014 the WHO declared the outbreak a public health emergency of international concern. Based on the number of deaths and total number of cases reported to the WHO as of August 11, 2014, the current outbreak has an overall mortality rate of 55%. Outbreak control measures against Ebola virus disease are effective. Why then, has this outbreak been so challenging to control? Ebola is transmitted through bodily fluids and immediately attacks the immune system, then progressively attacks the major organs and the lining of blood vessels. Sierra Leone, Guinea and Liberia are small countries that have limited resources to respond to prolonged outbreaks, especially in rural areas. This has been made more challenging by the fact that health care workers are at risk of contracting Ebola virus disease. Treatment to date has been supportive, not curative and outbreak control strategies have been met with distrust due to fear and misinformation. However, important progress is being made. The international response to Ebola is gaining momentum, communication strategies have been developed to address the fear and mistrust, and promising treatments are under development, including a combination of three monoclonal antibodies that has been administered to two American Ebola infected health care workers. The National Microbiology Laboratory of the Public Health Agency of Canada (PHAC) has been supporting laboratory diagnostic efforts in West Africa and PHAC has been working with the provinces and territories and key stakeholders to ensure Canada is prepared for a potential Ebola importation.
Neglected waterborne parasitic protozoa and their detection in water.
Plutzer, Judit; Karanis, Panagiotis
2016-09-15
Outbreak incidents raise the question of whether the less frequent aetiological agents of outbreaks are really less frequent in water. Alternatively, waterborne transmission could be relevant, but the lack of attention and rapid, sensitive methods to recover and detect the exogenous stages in water may keep them under-recognized. High quality information on the prevalence and detection of less frequent waterborne protozoa, such as Cyclospora cayetanensis, Toxoplasma gondii, Isospora belli, Balantidium coli, Blastocystis hominis, Entamoeba histolytica and other free-living amoebae (FLA), are not available. This present paper discusses the detection tools applied for the water surveillance of the neglected waterborne protozoa mentioned above and provides future perspectives. Copyright © 2016 Elsevier Ltd. All rights reserved.
Fresh Produce-Associated Listeriosis Outbreaks, Sources of Concern, Teachable Moments, and Insights.
Garner, Danisha; Kathariou, Sophia
2016-02-01
Foodborne transmission of Listeria monocytogenes was first demonstrated through the investigation of the 1981 Maritime Provinces outbreak involving coleslaw. In the following two decades, most listeriosis outbreaks involved foods of animal origin, e.g., deli meats, hot dogs, and soft cheeses. L. monocytogenes serotype 4b, especially epidemic clones I, II, and Ia, were frequently implicated in these outbreaks. However, since 2008 several outbreaks have been linked to diverse types of fresh produce: sprouts, celery, cantaloupe, stone fruit, and apples. The 2011 cantaloupe-associated outbreak was one of the deadliest foodborne outbreaks in recent U.S. history. This review discusses produce-related outbreaks of listeriosis with a focus on special trends, unusual findings, and potential paradigm shifts. With the exception of sprouts, implicated produce types were novel, and outbreaks were one-time events. Several involved serotype 1/2a, and in the 2011 cantaloupe-associated outbreak, serotype 1/2b was for the first time conclusively linked to a common-source outbreak of invasive listeriosis. Also in this outbreak, for the first time multiple strains were implicated in a common-source outbreak. In 2014, deployment of whole genome sequencing as part of outbreak investigation validated this technique as a pivotal tool for outbreak detection and speedy resolution. In spite of the unusual attributes of produce-related outbreaks, in all but one of the investigated cases (the possible exception being the coleslaw outbreak) contamination was traced to the same sources as those for outbreaks associated with other vehicles (e.g., deli meats), i.e., the processing environment and equipment. The public health impact of farm-level contamination remains uncharacterized. This review highlights knowledge gaps regarding virulence and other potentially unique attributes of produce outbreak strains, the potential for novel fresh produce items to become unexpectedly implicated in outbreaks, and the key role of good control strategies in the processing environment.
Discrimination of tornadic and non-tornadic severe weather outbreaks
NASA Astrophysics Data System (ADS)
Mercer, Andrew Edward
Outbreaks of severe weather affect the majority of the conterminous United States. An outbreak is characterized by multiple severe weather occurrences within a single synoptic system. Outbreaks can be categorized by whether or not they produce tornadoes. It is hypothesized that the antecedent synoptic signal contains important information about outbreak type. Accordingly, the scope of this research is to determine the extent that the synoptic signal can be utilized to classify outbreak type at various lead times. Outbreak types are classified using the NCEP/NCAR reanalysis data, which are arranged on a global 2.5° latitude-longitude grid, include 17 vertical pressure levels, and span from 1948 to the present (2008). Fifty major tornado outbreak (TO) cases and fifty major non-tornadic severe weather outbreak (NTO) cases are selected for this work. Two types of analyses are performed on these cases to assess discrimination ability. One analysis involves outbreak classification using the Weather Research and Forecasting (WRF) model initialized with the NCEP/NCAR reanalysis dataset. Meteorological covariates are computed from the WRF output and used in training and testing of statistical classification models. The covariate fields are depicted on a 21 X 21 gridpoint field with an 18 km grid spacing centered on the outbreak. Covariates with large discrimination potential are determined using permutation testing. A P-mode principal component analysis (PCA) is used on the subset of covariates determined by permutation testing to reduce data dimensionality, since numerous redundancies exist in the initial covariate set. Three statistical classification models are trained and tested with the resulting PC scores: a support vector machine (SVM), a logistic regression model (LogR), and a multiple linear regression model (LR). Promising results emerge from these methods, as a probability of detection (POD) of 0.89 and a false alarm ratio (FAR) of 0.13 are obtained from the best discriminating statistical technique (SVM) at 24-hours lead time. Results degrade only slightly by 72-hours lead time (maximum POD of 0.833 and minimum FAR of 0.276). Synoptic composites of the outbreak types are the second analysis considered. Composites are used to reveal synoptic features of outbreak types, which can be utilized to diagnose the differences between classes (in this case, TOs and NTOs). The composites are created using PCA. Five raw variables, height, temperature, relative humidity, and u and v wind components, are extracted from the NCEP/NCAR reanalysis data for North America. Converging longitude lines with increasing latitude on the reanalysis grid introduce bias into correlation calculations in higher latitudes; hence, the data are mapped onto both a latitudinal density grid and a Fibonacci grid. The resulting PCA produces two significant principal components (PCs), and a cluster analysis on these PCs for each outbreak type results in two types of TOs and NTOs. TO composites are characterized by a trough of low pressure over the central United States and major quasigeostrophic forcing features such as an upper level jet streak, cyclonic vorticity advection increasing with height, and warm air advection. These dynamics result in a strong surface cyclone in most tornado outbreaks. These features are considerably less pronounced in NTOs. The statistical analyses presented herein were successful in classifying outbreak types at various lead times, using synoptic scale data as input.
Lancee, William J.; Balderson, Kenneth E.; Bennett, Jocelyn P.; Borgundvaag, Bjug; Evans, Susan; Fernandes, Christopher M.B.; Goldbloom, David S.; Gupta, Mona; Hunter, Jonathan J.; Hall, Linda McGillis; Nagle, Lynn M.; Pain, Clare; Peczeniuk, Sonia S.; Raymond, Glenna; Read, Nancy; Rourke, Sean B.; Steinberg, Rosalie J.; Stewart, Thomas E.; Coke, Susan VanDeVelde; Veldhorst, Georgina G.; Wasylenki, Donald A.
2006-01-01
Healthcare workers (HCWs) found the 2003 outbreak of severe acute respiratory syndrome (SARS) to be stressful, but the long-term impact is not known. From 13 to 26 months after the SARS outbreak, 769 HCWs at 9 Toronto hospitals that treated SARS patients and 4 Hamilton hospitals that did not treat SARS patients completed a survey of several adverse outcomes. Toronto HCWs reported significantly higher levels of burnout (p = 0.019), psychological distress (p<0.001), and posttraumatic stress (p<0.001). Toronto workers were more likely to have reduced patient contact and work hours and to report behavioral consequences of stress. Variance in adverse outcomes was explained by a protective effect of the perceived adequacy of training and support and by a provocative effect of maladaptive coping style and other individual factors. The results reinforce the value of effective staff support and training in preparation for future outbreaks. PMID:17326946
Waterborne Pathogens: Detection Methods and Challenges
Ramírez-Castillo, Flor Yazmín; Loera-Muro, Abraham; Jacques, Mario; Garneau, Philippe; Avelar-González, Francisco Javier; Harel, Josée; Guerrero-Barrera, Alma Lilián
2015-01-01
Waterborne pathogens and related diseases are a major public health concern worldwide, not only by the morbidity and mortality that they cause, but by the high cost that represents their prevention and treatment. These diseases are directly related to environmental deterioration and pollution. Despite the continued efforts to maintain water safety, waterborne outbreaks are still reported globally. Proper assessment of pathogens on water and water quality monitoring are key factors for decision-making regarding water distribution systems’ infrastructure, the choice of best water treatment and prevention waterborne outbreaks. Powerful, sensitive and reproducible diagnostic tools are developed to monitor pathogen contamination in water and be able to detect not only cultivable pathogens but also to detect the occurrence of viable but non-culturable microorganisms as well as the presence of pathogens on biofilms. Quantitative microbial risk assessment (QMRA) is a helpful tool to evaluate the scenarios for pathogen contamination that involve surveillance, detection methods, analysis and decision-making. This review aims to present a research outlook on waterborne outbreaks that have occurred in recent years. This review also focuses in the main molecular techniques for detection of waterborne pathogens and the use of QMRA approach to protect public health. PMID:26011827
Allen, Heather A
2015-05-13
The merits of One Health have been thoroughly described in the literature, but how One Health operates in the United States federal system of government is rarely discussed or analyzed. Through a comparative case-study approach, this research explores how federalism, bureaucratic behavior, and institutional design in the United States may influence zoonotic disease outbreak detection and reporting, a key One Health activity. Using theoretical and empirical literature, as well as a survey/interview instrument for individuals directly involved in a past zoonotic disease outbreak, the impacts of governance are discussed. As predicted in the theoretical literature, empirical findings suggest that federalism, institutional design, and bureaucracy may play a role in facilitating or impeding zoonotic disease outbreak detection and reporting. Regulatory differences across states as well as compartmentalization of information within agencies may impede disease detection. However, the impact may not always be negative: bureaucracies can also be adaptive; federalism allows states important opportunities for innovation. While acknowledging there are many other factors that also matter in zoonotic disease detection and reporting, this research is one of the first attempts to raise awareness in the literature and stimulate discussion on the intersection of governance and One Health.
Low West Nile virus circulation in wild birds in an area of recurring outbreaks in Southern France.
Balança, Gilles; Gaidet, Nicolas; Savini, Giovanni; Vollot, Benjamin; Foucart, Antoine; Reiter, Paul; Boutonnier, Alain; Lelli, Rossella; Monicat, François
2009-12-01
West Nile virus (WNV) has a history of irregular but recurrent epizootics in countries of Mediterranean and of Central and Eastern Europe. We have investigated the temporal enzootic activity of WNV in free-ranging birds over a 3-year period in an area with sporadic occurrences of WNV outbreaks in Southern France. We conducted an intensive serologic survey on several wild bird populations (>4000 serum samples collected from 3300 birds) selected as potential indicators of the WNV circulation. WNV antibodies were detected by seroneutralization and/or plaque reduction neutralization in house sparrows, black-billed magpies, and scops owls, but these species appeared to be insufficient indicators of WNV circulation. Overall seroprevalence was low (<1%), including in birds that had been potentially exposed to the virus during recent outbreaks. However, the detection of a seroconversion in one bird, as well as the detection of seropositive birds in all years of our monitoring, including juveniles, indicate a constant annual circulation of WNV at a low level, including in years without any detectable emergence of WN fever in horses or humans.
Dedkov, V G; Magassouba, N' F; Safonova, M V; Deviatkin, A A; Dolgova, A S; Pyankov, O V; Sergeev, A A; Utkin, D V; Odinokov, G N; Safronov, V A; Agafonov, A P; Maleev, V V; Shipulin, G A
2016-02-01
In early February 2014, an outbreak of the Ebola virus disease caused by Zaire ebolavirus (EBOV) occurred in Guinea; cases were also recorded in other West African countries with a combined population of approximately 25 million. A rapid, sensitive and inexpensive method for detecting EBOV is needed to effectively control such outbreak. Here, we report a real-time reverse-transcription PCR assay for Z. ebolavirus detection used by the Specialized Anti-epidemic Team of the Russian Federation during the Ebola virus disease prevention mission in the Republic of Guinea. The analytical sensitivity of the assay is 5 × 10(2) viral particles per ml, and high specificity is demonstrated using representative sampling of viral, bacterial and human nucleic acids. This assay can be applied successfully for detecting the West African strains of Z. ebolavirus as well as on strains isolated in the Democratic Republic of the Congo in 2014. Copyright © 2015 Elsevier B.V. All rights reserved.
DETECTION OF OUTBREAK-ASSOCIATED HUMAN CALICIVIRUSES IN GROUNDWATER BY RT-PCR
Human caliciviruses (HuCV) are a major worldwide cause of food and waterborne outbreaks of acute nonbacterial gastroenteritis, and have been placed on the U.S. Environmental Protection Agency's (U.S. EPA) Contaminant Candidate List (CCL) of agents to be considered for regulatory ...
2005-01-01
In Singapore, the military was actively involved in the containment of the outbreak of severe acute respiratory syndrome (SARS) last year. The outbreak started in February 2003 with three Singapore travellers to Hong Kong. At that time, nothing was known about the aetiological agent of the atypical pneumonia that was termed SARS. Unfortunately one of the travellers was a super-spreader, defined as a person with high efficiency for virus transmission, and was responsible for the expansion of the national outbreak. Not only was the Singapore military involved in contact tracing of personnel and enforcement of home quarantine, military-affiliated research institutes were also involved in providing diagnostic support. This review reconstructs the events that took place during the SARS outbreak, focusing on the special support arising from complementing the military-affiliated laboratory with the public health laboratory. A description of the diagnostic findings is provided in chronological order. The review ends with lessons Singapore learnt from the SARS crisis, stressing the importance of national preparedness for future outbreaks. 2004 John Wiley & Sons, Ltd.
Response to a Large Polio Outbreak in a Setting of Conflict - Middle East, 2013-2015.
Mbaeyi, Chukwuma; Ryan, Michael J; Smith, Philip; Mahamud, Abdirahman; Farag, Noha; Haithami, Salah; Sharaf, Magdi; Jorba, Jaume C; Ehrhardt, Derek
2017-03-03
As the world advances toward the eradication of polio, outbreaks of wild poliovirus (WPV) in polio-free regions pose a substantial risk to the timeline for global eradication. Countries and regions experiencing active conflict, chronic insecurity, and large-scale displacement of persons are particularly vulnerable to outbreaks because of the disruption of health care and immunization services (1). A polio outbreak occurred in the Middle East, beginning in Syria in 2013 with subsequent spread to Iraq (2). The outbreak occurred 2 years after the onset of the Syrian civil war, resulted in 38 cases, and was the first time WPV was detected in Syria in approximately a decade (3,4). The national governments of eight countries designated the outbreak a public health emergency and collaborated with partners in the Global Polio Eradication Initiative (GPEI) to develop a multiphase outbreak response plan focused on improving the quality of acute flaccid paralysis (AFP) surveillance* and administering polio vaccines to >27 million children during multiple rounds of supplementary immunization activities (SIAs). † Successful implementation of the response plan led to containment and interruption of the outbreak within 6 months of its identification. The concerted approach adopted in response to this outbreak could serve as a model for responding to polio outbreaks in settings of conflict and political instability.
Healthcare-associated outbreaks due to Mucorales and other uncommon fungi.
Davoudi, Setareh; Graviss, Linda S; Kontoyiannis, Dimitrios P
2015-07-01
Healthcare-associated outbreaks of fungal infections, especially with uncommon and emerging fungi, have become more frequent in the past decade. Here, we reviewed the history and definition of healthcare-associated outbreaks of uncommon fungal infections and discussed the principles of investigating, containing and treatment of these outbreaks. In case of these uncommon diseases, occurrence of two or more cases in a short period is considered as an outbreak. Contaminated medical devices and hospital environment are the major sources of these outbreaks. Care must be taken to differentiate a real infection from colonization or contamination. Defining and identifying cases, describing epidemiologic feature of cases, finding and controlling the source of the outbreak, treating patients, and managing asymptomatic exposed patients are main steps for outbreak elimination. These fungal outbreaks are not only difficult to detect but also hard to treat. Early initiation of appropriate antifungal therapy is strongly associated with improved outcomes in infected patients. Choice of antifungal drugs should be made based on spectrum, pharmacodynamic and pharmacokinetic characteristics and adverse effects of available drugs. Combination antifungal therapy and surgical intervention may be also helpful in selected cases. A multidisciplinary approach and close collaboration between all key partners are necessary for successful control of fungal outbreaks. © 2015 Stichting European Society for Clinical Investigation Journal Foundation.
Loharikar, Anagha; Newton, Anna; Rowley, Patricia; Wheeler, Charlotte; Bruno, Tami; Barillas, Haroldo; Pruckler, James; Theobald, Lisa; Lance, Susan; Brown, Jeffrey M; Barzilay, Ezra J; Arvelo, Wences; Mintz, Eric; Fagan, Ryan
2012-07-01
Fifty-four outbreaks of domestically acquired typhoid fever were reported between 1960 and 1999. In 2010, the Southern Nevada Health District detected an outbreak of typhoid fever among persons who had not recently travelled abroad. We conducted a case-control study to examine the relationship between illness and exposures. A case was defined as illness with the outbreak strain of Salmonella serotype Typhi, as determined by pulsed-field gel electrophoresis (PFGE), with onset during 2010. Controls were matched by neighborhood, age, and sex. Bivariate and multivariate statistical analyses were completed using logistic regression. Traceback investigation was completed. We identified 12 cases in 3 states with onset from 15 April 2010 to 4 September 2010. The median age of case patients was 18 years (range, 4-48 years), 8 (67%) were female, and 11 (92%) were Hispanic. Nine (82%) were hospitalized; none died. Consumption of frozen mamey pulp in a fruit shake was reported by 6 of 8 case patients (75%) and none of the 33 controls (matched odds ratio, 33.9; 95% confidence interval, 4.9). Traceback investigations implicated 2 brands of frozen mamey pulp from a single manufacturer in Guatemala, which was also implicated in a 1998-1999 outbreak of typhoid fever in Florida. Reporting of individual cases of typhoid fever and subtyping of isolates by PFGE resulted in rapid detection of an outbreak associated with a ready-to-eat frozen food imported from a typhoid-endemic region. Improvements in food manufacturing practices and monitoring will prevent additional outbreaks.
Todkill, D; Elliot, A J; Morbey, R; Harris, J; Hawker, J; Edeghere, O; Smith, G E
2016-08-01
Syndromic surveillance systems in England have demonstrated utility in the early identification of seasonal gastrointestinal illness (GI) tracking its spatio-temporal distribution and enabling early public health action. There would be additional public health utility if syndromic surveillance systems could detect or track subnational infectious disease outbreaks. To investigate using syndromic surveillance for this purpose we retrospectively identified eight large GI outbreaks between 2009 and 2014 (four randomly and four purposively sampled). We then examined syndromic surveillance information prospectively collected by the Real-time Syndromic Surveillance team within Public Health England for evidence of possible outbreak-related changes. None of the outbreaks were identified contemporaneously and no alerts were made to relevant public health teams. Retrospectively, two of the outbreaks - which happened at similar times and in proximal geographical locations - demonstrated changes in the local trends of relevant syndromic indicators and exhibited a clustering of statistical alarms, but did not warrant alerting local health protection teams. Our suite of syndromic surveillance systems may be more suited to their original purposes than as means of detecting or monitoring localized, subnational GI outbreaks. This should, however, be considered in the context of this study's limitations; further prospective work is needed to fully explore the use of syndromic surveillance for this purpose. Provided geographical coverage is sufficient, syndromic surveillance systems could be able to provide reassurance of no or minor excess healthcare systems usage during localized GI incidents.
Yasmin, Rubina; Barber, Cheryl A.; Castro, Talita; Malamud, Daniel; Kim, Beum Jun; Zhu, Hui; Montagna, Richard A.; Abrams, William R.
2018-01-01
In recent years, there have been increasing numbers of infectious disease outbreaks that spread rapidly to population centers resulting from global travel, population vulnerabilities, environmental factors, and ecological disasters such as floods and earthquakes. Some examples of the recent outbreaks are the Ebola epidemic in West Africa, Middle East respiratory syndrome coronavirus (MERS-Co) in the Middle East, and the Zika outbreak through the Americas. We have created a generic protocol for detection of pathogen RNA and/or DNA using loop-mediated isothermal amplification (LAMP) and reverse dot-blot for detection (RDB) and processed automatically in a microfluidic device. In particular, we describe how a microfluidic assay to detect HIV viral RNA was converted to detect Zika virus (ZIKV) RNA. We first optimized the RT-LAMP assay to detect ZIKV RNA using a benchtop isothermal amplification device. Then we implemented the assay in a microfluidic device that will allow analyzing 24 samples simultaneously and automatically from sample introduction to detection by RDB technique. Preliminary data using saliva samples spiked with ZIKV showed that our diagnostic system detects ZIKV RNA in saliva. These results will be validated in further experiments with well-characterized ZIKV human specimens of saliva. The described strategy and methodology to convert the HIV diagnostic assay and platform to a ZIKV RNA detection assay provides a model that can be readily utilized for detection of the next emerging or re-emerging infectious disease. PMID:29401479
Sabalza, Maite; Yasmin, Rubina; Barber, Cheryl A; Castro, Talita; Malamud, Daniel; Kim, Beum Jun; Zhu, Hui; Montagna, Richard A; Abrams, William R
2018-01-01
In recent years, there have been increasing numbers of infectious disease outbreaks that spread rapidly to population centers resulting from global travel, population vulnerabilities, environmental factors, and ecological disasters such as floods and earthquakes. Some examples of the recent outbreaks are the Ebola epidemic in West Africa, Middle East respiratory syndrome coronavirus (MERS-Co) in the Middle East, and the Zika outbreak through the Americas. We have created a generic protocol for detection of pathogen RNA and/or DNA using loop-mediated isothermal amplification (LAMP) and reverse dot-blot for detection (RDB) and processed automatically in a microfluidic device. In particular, we describe how a microfluidic assay to detect HIV viral RNA was converted to detect Zika virus (ZIKV) RNA. We first optimized the RT-LAMP assay to detect ZIKV RNA using a benchtop isothermal amplification device. Then we implemented the assay in a microfluidic device that will allow analyzing 24 samples simultaneously and automatically from sample introduction to detection by RDB technique. Preliminary data using saliva samples spiked with ZIKV showed that our diagnostic system detects ZIKV RNA in saliva. These results will be validated in further experiments with well-characterized ZIKV human specimens of saliva. The described strategy and methodology to convert the HIV diagnostic assay and platform to a ZIKV RNA detection assay provides a model that can be readily utilized for detection of the next emerging or re-emerging infectious disease.
Evaluation of a Multivariate Syndromic Surveillance System for West Nile Virus.
Faverjon, Céline; Andersson, M Gunnar; Decors, Anouk; Tapprest, Jackie; Tritz, Pierre; Sandoz, Alain; Kutasi, Orsolya; Sala, Carole; Leblond, Agnès
2016-06-01
Various methods are currently used for the early detection of West Nile virus (WNV) but their outputs are not quantitative and/or do not take into account all available information. Our study aimed to test a multivariate syndromic surveillance system to evaluate if the sensitivity and the specificity of detection of WNV could be improved. Weekly time series data on nervous syndromes in horses and mortality in both horses and wild birds were used. Baselines were fitted to the three time series and used to simulate 100 years of surveillance data. WNV outbreaks were simulated and inserted into the baselines based on historical data and expert opinion. Univariate and multivariate syndromic surveillance systems were tested to gauge how well they detected the outbreaks; detection was based on an empirical Bayesian approach. The systems' performances were compared using measures of sensitivity, specificity, and area under receiver operating characteristic curve (AUC). When data sources were considered separately (i.e., univariate systems), the best detection performance was obtained using the data set of nervous symptoms in horses compared to those of bird and horse mortality (AUCs equal to 0.80, 0.75, and 0.50, respectively). A multivariate outbreak detection system that used nervous symptoms in horses and bird mortality generated the best performance (AUC = 0.87). The proposed approach is suitable for performing multivariate syndromic surveillance of WNV outbreaks. This is particularly relevant, given that a multivariate surveillance system performed better than a univariate approach. Such a surveillance system could be especially useful in serving as an alert for the possibility of human viral infections. This approach can be also used for other diseases for which multiple sources of evidence are available.
Livnat, Yarden; Galli, Nathan; Samore, Matthew H; Gundlapalli, Adi V
2012-01-01
Advances in surveillance science have supported public health agencies in tracking and responding to disease outbreaks. Increasingly, epidemiologists have been tasked with interpreting multiple streams of heterogeneous data arising from varied surveillance systems. As a result public health personnel have experienced an overload of plots and charts as information visualization techniques have not kept pace with the rapid expansion in data availability. This study sought to advance the science of public health surveillance data visualization by conceptualizing a visual paradigm that provides an ‘epidemiological canvas’ for detection, monitoring, exploration and discovery of regional infectious disease activity and developing a software prototype of an ‘infectious disease weather map'. Design objectives were elucidated and the conceptual model was developed using cognitive task analysis with public health epidemiologists. The software prototype was pilot tested using retrospective data from a large, regional pediatric hospital, and gastrointestinal and respiratory disease outbreaks were re-created as a proof of concept. PMID:22358039
The Emergency campaign for smallpox eradication from Somalia (1977-1979)--revisited.
Deria, Abdullahi
2011-12-30
The historical significance of smallpox eradication from Somalia lies in the fact that the country was the last to record the last endemic smallpox case in the world. Before 1977 the programme was mismanaged. In the mid-1970s, the programme was plagued with concealment. Confirmation of smallpox outbreak in Mogadishu in September 1976 delayed global smallpox eradication. The Government maintained that there was no ongoing smallpox transmission in the country after the Mogadishu outbreak and frustrated independent attempts to verify its claim. In February 1977 the Government allowed World Health Organization (WHO) epidemiologists to search, unhindered, for smallpox outside Mogadishu. Soon widespread smallpox transmission was detected. The Government appealed for international support. The strategy to stop the smallpox transmission was based on surveillance and containment. The WHO took the leading role of the campaign which, in spite of the Somalia/Ethiopia war of 1977/78, culminated in the eradication of smallpox from the country. Somalia was certified smallpox-free on 19 October 1979. Copyright © 2011 Elsevier Ltd. All rights reserved.
Cassell, Cynthia H.; Bunnell, Rebecca E.; Angulo, Frederick J.; Craig, Allen; Pesik, Nicki; Dahl, Benjamin A.; Ijaz, Kashef; Jafari, Hamid; Martin, Rebecca
2017-01-01
To achieve compliance with the revised World Health Organization International Health Regulations (IHR 2005), countries must be able to rapidly prevent, detect, and respond to public health threats. Most nations, however, remain unprepared to manage and control complex health emergencies, whether due to natural disasters, emerging infectious disease outbreaks, or the inadvertent or intentional release of highly pathogenic organisms. The US Centers for Disease Control and Prevention (CDC) works with countries and partners to build and strengthen global health security preparedness so they can quickly respond to public health crises. This report highlights selected CDC global health protection platform accomplishments that help mitigate global health threats and build core, cross-cutting capacity to identify and contain disease outbreaks at their source. CDC contributions support country efforts to achieve IHR 2005 compliance, contribute to the international framework for countering infectious disease crises, and enhance health security for Americans and populations around the world. PMID:29155656
Specificity of coliphages in evaluating marker efficacy: a new insight for water quality indicators.
Mookerjee, Subham; Batabyal, Prasenjit; Halder, Madhumanti; Palit, Anup
2014-11-01
Conventional procedures for qualitative assessment of coliphage are time consuming multiple step approach for achieving results. A modified and rapid technique has been introduced for determination of coliphage contamination among potable water sources during water borne outbreaks. During December 2013, 40 water samples from different potable water sources, were received for water quality analyses, from a jaundice affected Municipality of West Bengal, India. Altogether, 30% water samples were contaminated with coliform (1-20 cfu/ml) and 5% with E. coli (2-5 cfu/ml). Among post-outbreak samples, preponderance of coliform has decreased (1-4 cfu/ml) with total absence of E. coli. While standard technique has detected 55% outbreak samples with coliphage contamination, modified technique revealed that 80%, double than that of bacteriological identification rate, were contaminated with coliphages (4-20 pfu/10 ml). However, post-outbreak samples were detected with 1-5 pfu/10 ml coliphages among 20% samples. Coliphage detection rate through modified technique was nearly double (50%) than that of standard technique (27.5%). In few samples (with coliform load of 10-100 cfu/ml), while modified technique could detect coliphages among six samples (10-20 pfu/10 ml), standard protocol failed to detect coliphage in any of them. An easy, rapid and accurate modified technique has thereby been implemented for coliphage assessment from water samples. Coliform free water does not always signify pathogen free potable water and it is demonstrated that coliphage is a more reliable 'biomarker' to ascertain contamination level in potable water. Copyright © 2014 Elsevier B.V. All rights reserved.
Klinkenberg, Don; Thomas, Ekelijn; Artavia, Francisco F Calvo; Bouma, Annemarie
2011-08-01
Design of surveillance programs to detect infections could benefit from more insight into sampling schemes. We address the effect of sampling schemes for Salmonella Enteritidis surveillance in laying hens. Based on experimental estimates for the transmission rate in flocks, and the characteristics of an egg immunological test, we have simulated outbreaks with various sampling schemes, and with the current boot swab program with a 15-week sampling interval. Declaring a flock infected based on a single positive egg was not possible because test specificity was too low. Thus, a threshold number of positive eggs was defined to declare a flock infected, and, for small sample sizes, eggs from previous samplings had to be included in a cumulative sample to guarantee a minimum flock level specificity. Effectiveness of surveillance was measured by the proportion of outbreaks detected, and by the number of contaminated table eggs brought on the market. The boot swab program detected 90% of the outbreaks, with 75% fewer contaminated eggs compared to no surveillance, whereas the baseline egg program (30 eggs each 15 weeks) detected 86%, with 73% fewer contaminated eggs. We conclude that a larger sample size results in more detected outbreaks, whereas a smaller sampling interval decreases the number of contaminated eggs. Decreasing sample size and interval simultaneously reduces the number of contaminated eggs, but not indefinitely: the advantage of more frequent sampling is counterbalanced by the cumulative sample including less recently laid eggs. Apparently, optimizing surveillance has its limits when test specificity is taken into account. © 2011 Society for Risk Analysis.
Gao, Zhiyong; Liu, Baiwei; Huo, Da; Yan, Hanqiu; Jia, Lei; Du, Yiwei; Qian, Haikun; Yang, Yang; Wang, Xiaoli; Li, Jie; Wang, Quanyi
2015-12-18
Norovirus (NoV) is a leading cause of sporadic cases and outbreaks of acute gastroenteritis (AGE). Increased NoV activity was observed in Beijing, China during winter 2014-2015; therefore, we examined the epidemiological patterns and genetic characteristics of NoV in the sporadic cases and outbreaks. The weekly number of infectious diarrhea cases reported by all hospitals in Beijing was analyzed through the China information system for disease control and prevention. Fecal specimens were collected from the outbreaks and outpatients with AGE, and GI and GII NoVs were detected using real time reverse transcription polymerase chain reaction. The partial capsid genes and RNA-dependent RNA polymerase (RdRp) genes of NoV were both amplified and sequenced, and genotyping and phylogenetic analyses were performed. Between December 2014 and March 2015, the number of infectious diarrhea cases in Beijing (10,626 cases) increased by 35.6% over that of the previous year (7835 cases), and the detection rate of NoV (29.8%, 191/640) among outpatients with AGE was significantly higher than in the previous year (12.9%, 79/613) (χ(2) = 53.252, P < 0.001). Between November 2014 and March 2015, 35 outbreaks of AGE were reported in Beijing, and NoVs were detected in 33 outbreaks, all of which belonged to the GII genogroup. NoVs were sequenced and genotyped in 22 outbreaks, among which 20 were caused by a novel GII.17 strain. Among outpatients with AGE, this novel GII.17 strain was first detected in an outpatient in August 2014, and it replaced GII.4 Sydney_2012 as the predominant variant between December 2014 and March 2015. A phylogenetic analysis of the capsid genes and RdRp genes revealed that this novel GII.17 strain was distinct from previously identified GII variants, and it was recently designated as GII.P17_GII.17. This variant was further clustered into two sub-groups, named GII.17_2012 and GII.17_2014. During winter 2014-2015, GII.17_2014 caused the majority of AGE outbreaks in China and Japan. During winter 2014-2015, a novel NoV GII.17 variant replaced the GII.4 variant Sydney 2012 as the predominant strain in Beijing, China and caused increased NoV activity.
Detecting European Rabbit ( Oryctolagus cuniculus) Disease Outbreaks by Monitoring Digital Media.
Peacock, David E; Grillo, Tiggy L
2018-04-18
Digital media and digital search tools offer simple and effective means to monitor for pathogens and disease outbreaks in target organisms. Using tools such as Rich Site Summary feeds, and Google News and Google Scholar specific key word searches, international digital media were actively monitored from 2012 to 2016 for pathogens and disease outbreaks in the taxonomic order Lagomorpha, with a specific focus on the European rabbit ( Oryctolagus cuniculus). The primary objective was identifying pathogens for assessment as potential new biocontrol agents for Australia's pest populations of the European rabbit. A number of pathogens were detected in digital media reports. Additional benefits arose in the regular provision of case reports and research on myxomatosis and rabbit haemorrhagic disease virus that assisted with current research.
Trigger events: enviroclimatic coupling of Ebola hemorrhagic fever outbreaks
NASA Technical Reports Server (NTRS)
Pinzon, Jorge E.; Wilson, James M.; Tucker, Compton J.; Arthur, Ray; Jahrling, Peter B.; Formenty, Pierre
2004-01-01
We use spatially continuous satellite data as a correlate of precipitation within tropical Africa and show that the majority of documented Ebola hemorrhagic fever outbreaks were closely associated with sharply drier conditions at the end of the rainy season. We propose that these trigger events may enhance transmission of Ebola virus from its cryptic reservoir to humans. These findings suggest specific directions to help understand the sylvatic cycle of the virus and may provide early warning tools to detect possible future outbreaks of this enigmatic disease.
Detection of a chikungunya outbreak in Central Italy, August to September 2017.
Venturi, Giulietta; Di Luca, Marco; Fortuna, Claudia; Remoli, Maria Elena; Riccardo, Flavia; Severini, Francesco; Toma, Luciano; Del Manso, Martina; Benedetti, Eleonora; Caporali, Maria Grazia; Amendola, Antonello; Fiorentini, Cristiano; De Liberato, Claudio; Giammattei, Roberto; Romi, Roberto; Pezzotti, Patrizio; Rezza, Giovanni; Rizzo, Caterina
2017-09-01
An autochthonous chikungunya outbreak is ongoing near Anzio, a coastal town in the province of Rome. The virus isolated from one patient and mosquitoes lacks the A226V mutation and belongs to an East Central South African strain. As of 20 September, 86 cases are laboratory-confirmed. The outbreak proximity to the capital, its late summer occurrence, and diagnostic delays, are favouring transmission. Vector control, enhanced surveillance and restricted blood donations are being implemented in affected areas.
Doppler weather radar detects emigratory flights of noctuids during a major pest outbreak
USDA-ARS?s Scientific Manuscript database
An outbreak of beet armyworm (Spodoptera exigua (Hübner)), cabbage looper, (Trichoplusia ni (Hübner)), and other lepidopteran pests devastated cotton production in the Lower Rio Grande Valley TX, in 1995. Major infestations occurred later in the year several hundred kilometers away in other cotton ...
A MULTIPLEX REVERSE TRANSCIPTION-PCR METHOD FOR DETECTION OF HUMAN ENTERIC VIRUSES IN GROUNDWATER
Untreated groundwater is responsible for about half of the waterborne disease outbreaks in the United States. Human enteric viruses are thought to be leading etiological agents of many of these outbreaks, but there is relatively little information on the types and levels of viru...
Navas, Encarna; Torner, Nuria; Broner, Sonia; Godoy, Pere; Martínez, Ana; Bartolomé, Rosa; Domínguez, Angela
2015-10-01
To determine the direct and indirect costs of outbreaks of acute viral gastroenteritis (AVG) due to norovirus in closed institutions (hospitals, social health centers or nursing homes) and the community in Catalonia in 2010-11. Information on outbreaks were gathered from the reports made by epidemiological surveillance units. Direct costs (medical visits, hospital stays, drug treatment, sample processing, transport, diagnostic tests, monitoring and control of the outbreaks investigated) and indirect costs (lost productivity due to work absenteeism, caregivers time and working hours lost due to medical visits) were calculated. Twenty-seven outbreaks affecting 816 people in closed institutions and 74 outbreaks affecting 1,940 people in the community were detected. The direct and indirect costs of outbreaks were € 131,997.36 (€ 4,888.79 per outbreak) in closed institutions and € 260,557.16 (€ 3,521.04 per outbreak) in community outbreaks. The cost per case was € 161.76 in outbreaks in closed institutions and € 134.31 in community outbreaks. The main costs were surveillance unit monitoring (€ 116,652.93), laboratory diagnoses (€ 119,950.95), transport of samples (€ 69,970.90), medical visits (€ 25,250.50) and hospitalization (€ 13,400.00). The cost of outbreaks of acute viral gastroenteritis due to norovirus obtained in this study was influenced by the number of people affected and the severity of the outbreak, which determined hospitalizations and work absenteeism. Urgent reporting of outbreaks would allow the implementation of control measures that could reduce the numbers affected and the duration of the illness and thus the costs derived from them.
Struchen, R; Vial, F; Andersson, M G
2017-04-26
Delayed reporting of health data may hamper the early detection of infectious diseases in surveillance systems. Furthermore, combining multiple data streams, e.g. aiming at improving a system's sensitivity, can be challenging. In this study, we used a Bayesian framework where the result is presented as the value of evidence, i.e. the likelihood ratio for the evidence under outbreak versus baseline conditions. Based on a historical data set of routinely collected cattle mortality events, we evaluated outbreak detection performance (sensitivity, time to detection, in-control run length) under the Bayesian approach among three scenarios: presence of delayed data reporting, but not accounting for it; presence of delayed data reporting accounted for; and absence of delayed data reporting (i.e. an ideal system). Performance on larger and smaller outbreaks was compared with a classical approach, considering syndromes separately or combined. We found that the Bayesian approach performed better than the classical approach, especially for the smaller outbreaks. Furthermore, the Bayesian approach performed similarly well in the scenario where delayed reporting was accounted for to the scenario where it was absent. We argue that the value of evidence framework may be suitable for surveillance systems with multiple syndromes and delayed reporting of data.
Osaka, K; Inouye, S; Okabe, N; Taniguchi, K; Izumiya, H; Watanabe, H; Matsumoto, Y; Yokota, T; Hashimoto, S; Sagara, H
1999-12-01
The Traveller's Diarrhoea Network, by which the Infectious Disease Surveillance Center is electronically connected with two major airport quarantine stations and three infectious disease hospitals, was launched in February 1988 in Japan. The data on travellers' diarrhoea detected is reported weekly by e-mail. Two clusters of infection among travellers returning from Italy were reported by two airport quarantine stations at the end of September 1998. A total of 12 salmonella isolates from 2 clusters were examined. All were identified as Salmonella enteritidis, phage type 4 and showed identical banding patterns on pulsed-field gel electrophoresis. A case-control study showed that the scrambled eggs served at the hotel restaurant in Rome were the likely source of this outbreak. This outbreak could not have been detected promptly and investigated easily without the e-mail network. International exchange of data on travellers' diarrhoea is important for preventing and controlling food-borne illnesses infected abroad.
Critical dynamics in population vaccinating behavior.
Pananos, A Demetri; Bury, Thomas M; Wang, Clara; Schonfeld, Justin; Mohanty, Sharada P; Nyhan, Brendan; Salathé, Marcel; Bauch, Chris T
2017-12-26
Vaccine refusal can lead to renewed outbreaks of previously eliminated diseases and even delay global eradication. Vaccinating decisions exemplify a complex, coupled system where vaccinating behavior and disease dynamics influence one another. Such systems often exhibit critical phenomena-special dynamics close to a tipping point leading to a new dynamical regime. For instance, critical slowing down (declining rate of recovery from small perturbations) may emerge as a tipping point is approached. Here, we collected and geocoded tweets about measles-mumps-rubella vaccine and classified their sentiment using machine-learning algorithms. We also extracted data on measles-related Google searches. We find critical slowing down in the data at the level of California and the United States in the years before and after the 2014-2015 Disneyland, California measles outbreak. Critical slowing down starts growing appreciably several years before the Disneyland outbreak as vaccine uptake declines and the population approaches the tipping point. However, due to the adaptive nature of coupled behavior-disease systems, the population responds to the outbreak by moving away from the tipping point, causing "critical speeding up" whereby resilience to perturbations increases. A mathematical model of measles transmission and vaccine sentiment predicts the same qualitative patterns in the neighborhood of a tipping point to greatly reduced vaccine uptake and large epidemics. These results support the hypothesis that population vaccinating behavior near the disease elimination threshold is a critical phenomenon. Developing new analytical tools to detect these patterns in digital social data might help us identify populations at heightened risk of widespread vaccine refusal. Copyright © 2017 the Author(s). Published by PNAS.
Critical dynamics in population vaccinating behavior
Pananos, A. Demetri; Bury, Thomas M.; Wang, Clara; Schonfeld, Justin; Mohanty, Sharada P.; Nyhan, Brendan; Bauch, Chris T.
2017-01-01
Vaccine refusal can lead to renewed outbreaks of previously eliminated diseases and even delay global eradication. Vaccinating decisions exemplify a complex, coupled system where vaccinating behavior and disease dynamics influence one another. Such systems often exhibit critical phenomena—special dynamics close to a tipping point leading to a new dynamical regime. For instance, critical slowing down (declining rate of recovery from small perturbations) may emerge as a tipping point is approached. Here, we collected and geocoded tweets about measles–mumps–rubella vaccine and classified their sentiment using machine-learning algorithms. We also extracted data on measles-related Google searches. We find critical slowing down in the data at the level of California and the United States in the years before and after the 2014–2015 Disneyland, California measles outbreak. Critical slowing down starts growing appreciably several years before the Disneyland outbreak as vaccine uptake declines and the population approaches the tipping point. However, due to the adaptive nature of coupled behavior–disease systems, the population responds to the outbreak by moving away from the tipping point, causing “critical speeding up” whereby resilience to perturbations increases. A mathematical model of measles transmission and vaccine sentiment predicts the same qualitative patterns in the neighborhood of a tipping point to greatly reduced vaccine uptake and large epidemics. These results support the hypothesis that population vaccinating behavior near the disease elimination threshold is a critical phenomenon. Developing new analytical tools to detect these patterns in digital social data might help us identify populations at heightened risk of widespread vaccine refusal. PMID:29229821
Rumore, Jillian Leigh; Tschetter, Lorelee; Nadon, Celine
2016-05-01
The lack of pattern diversity among pulsed-field gel electrophoresis (PFGE) profiles for Escherichia coli O157:H7 in Canada does not consistently provide optimal discrimination, and therefore, differentiating temporally and/or geographically associated sporadic cases from potential outbreak cases can at times impede investigations. To address this limitation, DNA sequence-based methods such as multilocus variable-number tandem-repeat analysis (MLVA) have been explored. To assess the performance of MLVA as a supplemental method to PFGE from the Canadian perspective, a retrospective analysis of all E. coli O157:H7 isolated in Canada from January 2008 to December 2012 (inclusive) was conducted. A total of 2285 E. coli O157:H7 isolates and 63 clusters of cases (by PFGE) were selected for the study. Based on the qualitative analysis, the addition of MLVA improved the categorization of cases for 60% of clusters and no change was observed for ∼40% of clusters investigated. In such situations, MLVA serves to confirm PFGE results, but may not add further information per se. The findings of this study demonstrate that MLVA data, when used in combination with PFGE-based analyses, provide additional resolution to the detection of clusters lacking PFGE diversity as well as demonstrate good epidemiological concordance. In addition, MLVA is able to identify cluster-associated isolates with variant PFGE pattern combinations that may have been previously missed by PFGE alone. Optimal laboratory surveillance in Canada is achieved with the application of PFGE and MLVA in tandem for routine surveillance, cluster detection, and outbreak response.
Resource-driven encounters among consumers and implications for the spread of infectious disease
Flynn, Jason M.
2017-01-01
Animals share a variety of common resources, which can be a major driver of conspecific encounter rates. In this work, we implement a spatially explicit mathematical model for resource visitation behaviour in order to examine how changes in resource availability can influence the rate of encounters among consumers. Using simulations and asymptotic analysis, we demonstrate that, under a reasonable set of assumptions, the relationship between resource availability and consumer conspecific encounters is not monotonic. We characterize how the maximum encounter rate and associated critical resource density depend on system parameters like consumer density and the maximum distance from which consumers can detect and respond to resources. The assumptions underlying our theoretical model and analysis are motivated by observations of large aggregations of black-backed jackals at carcasses generated by seasonal outbreaks of anthrax among herbivores in Etosha National Park, Namibia. As non-obligate scavengers, black-backed jackals use carcasses as a supplemental food resource when they are available. While jackals do not appear to acquire disease from ingesting anthrax carcasses, changes in their movement patterns in response to changes in carcass abundance do alter jackals' conspecific encounter rate in ways that may affect the transmission dynamics of other diseases, such as rabies. Our theoretical results provide a method to quantify and analyse the hypothesis that the outbreak of a fatal disease among herbivores can potentially facilitate outbreaks of an entirely different disease among jackals. By analysing carcass visitation data, we find support for our model's prediction that the number of conspecific encounters at resource sites decreases with additional increases in resource availability. Whether or not this site-dependent effect translates to an overall decrease in encounters depends, unexpectedly, on the relationship between the maximum distance of detection and the resource density. PMID:29021163
Environmental Survey of Drinking Water Sources in Kampala, Uganda, during a Typhoid Fever Outbreak.
Murphy, J L; Kahler, A M; Nansubuga, I; Nanyunja, E M; Kaplan, B; Jothikumar, N; Routh, J; Gómez, G A; Mintz, E D; Hill, V R
2017-12-01
In 2015, a typhoid fever outbreak began in downtown Kampala, Uganda, and spread into adjacent districts. In response, an environmental survey of drinking water source types was conducted in areas of the city with high case numbers. A total of 122 samples was collected from 12 source types and tested for Escherichia coli , free chlorine, and conductivity. An additional 37 grab samples from seven source types and 16 paired large volume (20 liter) samples from wells and springs were also collected and tested for the presence of Salmonella enterica serovar Typhi. Escherichia coli was detected in 60% of kaveras (drinking water sold in plastic bags) and 80% of refilled water bottles; free chlorine was not detected in either source type. Most jerry cans (68%) contained E. coli and had free chlorine residuals below the WHO-recommended level of 0.5 mg/liter during outbreaks. Elevated conductivity readings for kaveras, refilled water bottles, and jerry cans (compared to treated surface water supplied by the water utility) suggested that they likely contained untreated groundwater. All unprotected springs and wells and more than 60% of protected springs contained E. coli Water samples collected from the water utility were found to have acceptable free chlorine levels and no detectable E. coli While S Typhi was not detected in water samples, Salmonella spp. were detected in samples from two unprotected springs, one protected spring, and one refilled water bottle. These data provided clear evidence that unregulated vended water and groundwater represented a risk for typhoid transmission. IMPORTANCE Despite the high incidence of typhoid fever globally, relatively few outbreak investigations incorporate drinking water testing. During waterborne disease outbreaks, measurement of physical-chemical parameters, such as free chlorine residual and electrical conductivity, and of microbiological parameters, such as the presence of E. coli or the implicated etiologic agent, in drinking water samples can identify contaminated sources. This investigation indicated that unregulated vended water and groundwater sources were contaminated and were therefore a risk to consumers during the 2015 typhoid fever outbreak in Kampala. Identification of contaminated drinking water sources and sources that do not contain adequate disinfectant levels can lead to rapid targeted interventions. Copyright © 2017 American Society for Microbiology.
Rastawicki, Waldemar; Kałużewski, Stanisław
2015-01-01
The laboratory diagnosis of typhoid fever is dependent upon either isolation of S. Typhi from a clinical sample or the detection of raised titers of serum antibodies in the Widal test or the passive hemagglutination assay (PHA). In this study we evaluated the usefulness of ELISA for detection of antibodies to S. Typhi lipopolysaccharide O and capsular polysaccharide Vi antigens in the sera of persons from outbreak of typhoid fever. Fifteen serum samples from patients with laboratory confirmed typhoid fever and 140 sera from persons suspected for contact with typhoid fever patients from outbreak in 1974/75 in Poland were tested by ELISA. Additionally, as the control group, we tested 115 sera from blood donors for the presence of S. Typhi anti-LPS and anti-Vi antibodies. Anti-LPS and anti-Vi antibodies were detected in 80% and 53.3% of sera obtained from patients with laboratory confirmed typhoid fever, respectively. The high percentages of positive results in ELISA were also noted in the group of persons suspected for contact with typhoid fever patients (51.4% and 45%) but not in the group of blood donors (7.8% and 6.1%, respectively). The ELISA could be a useful tool for the serological diagnosis of typhoid fever in patients who have clinical symptoms but are culture negative, especially during massive outbreaks of typhoid fever.
Neil, Karen P; Sodha, Samir V; Lukwago, Luswa; O-Tipo, Shikanga; Mikoleit, Matthew; Simington, Sherricka D; Mukobi, Peter; Balinandi, Stephen; Majalija, Samuel; Ayers, Joseph; Kagirita, Atek; Wefula, Edward; Asiimwe, Frank; Kweyamba, Vianney; Talkington, Deborah; Shieh, Wun-Ju; Adem, Patricia; Batten, Brigid C; Zaki, Sherif R; Mintz, Eric
2012-04-01
Salmonella enterica serovar Typhi (Salmonella Typhi) causes an estimated 22 million typhoid fever cases and 216 000 deaths annually worldwide. In Africa, the lack of laboratory diagnostic capacity limits the ability to recognize endemic typhoid fever and to detect outbreaks. We report a large laboratory-confirmed outbreak of typhoid fever in Uganda with a high proportion of intestinal perforations (IPs). A suspected case of typhoid fever was defined as fever and abdominal pain in a person with either vomiting, diarrhea, constipation, headache, weakness, arthralgia, poor response to antimalarial medications, or IP. From March 4, 2009 to April 17, 2009, specimens for blood and stool cultures and serology were collected from suspected cases. Antimicrobial susceptibility testing and pulsed-field gel electrophoresis (PFGE) were performed on Salmonella Typhi isolates. Surgical specimens from patients with IP were examined. A community survey was conducted to characterize the extent of the outbreak. From December 27, 2007 to July 30, 2009, 577 cases, 289 hospitalizations, 249 IPs, and 47 deaths from typhoid fever occurred; Salmonella Typhi was isolated from 27 (33%) of 81 patients. Isolates demonstrated multiple PFGE patterns and uniform susceptibility to ciprofloxacin. Surgical specimens from 30 patients were consistent with typhoid fever. Estimated typhoid fever incidence in the community survey was 8092 cases per 100 000 persons. This typhoid fever outbreak was detected because of an elevated number of IPs. Underreporting of milder illnesses and delayed and inadequate antimicrobial treatment contributed to the high perforation rate. Enhancing laboratory capacity for detection is critical to improving typhoid fever control.
Díaz, Luis Adrian; Albrieu Llinás, Guillermo; Vázquez, Ana; Tenorio, Antonio; Contigiani, Marta Silvia
2012-01-01
St. Louis encephalitis virus is a complex zoonoses. In 2005, 47 laboratory-confirmed and probable clinical cases of SLEV infection were reported in Córdoba, Argentina. Although the causes of 2005 outbreak remain unknown, they might be related not only to virological factors, but also to ecological and environmental conditions. We hypothesized that one of the factors for SLE reemergence in Córdoba, Argentina, was the introduction of a new SLEV genotype (SLEV genotype III), with no previous activity in the area. In order to evaluate this hypothesis we carried out a molecular characterization of SLEV detections from mosquitoes collected between 2001 and 2004 in Córdoba city. A total of 315 mosquito pools (11,002 individuals) including 12 mosquitoes species were analyzed. Overall, 20 pools (8 mosquitoes species) were positive for SLEV. During this study, genotypes II, V and VII were detected. No mosquito pool infected with genotype III was detected before the 2005 outbreak. Genotype V was found every year and in the 8 sampled sites. Genotypes II and VII showed limited temporal and spatial activities. We cannot dismiss the association of genotype II and V as etiological agents during the outbreak. However, the silent circulation of other SLEV strains in Córdoba city before the 2005 outbreak suggests that the introduction of genotype III was an important factor associated to this event. Not mutually exclusive, other factors such as changes in avian hosts and mosquitoes vectors communities, driven by climatic and environmental modifications, should also be taken into consideration in further studies. PMID:22303490
Thompson, Robin N.; Gilligan, Christopher A.; Cunniffe, Nik J.
2016-01-01
We assess how presymptomatic infection affects predictability of infectious disease epidemics. We focus on whether or not a major outbreak (i.e. an epidemic that will go on to infect a large number of individuals) can be predicted reliably soon after initial cases of disease have appeared within a population. For emerging epidemics, significant time and effort is spent recording symptomatic cases. Scientific attention has often focused on improving statistical methodologies to estimate disease transmission parameters from these data. Here we show that, even if symptomatic cases are recorded perfectly, and disease spread parameters are estimated exactly, it is impossible to estimate the probability of a major outbreak without ambiguity. Our results therefore provide an upper bound on the accuracy of forecasts of major outbreaks that are constructed using data on symptomatic cases alone. Accurate prediction of whether or not an epidemic will occur requires records of symptomatic individuals to be supplemented with data concerning the true infection status of apparently uninfected individuals. To forecast likely future behavior in the earliest stages of an emerging outbreak, it is therefore vital to develop and deploy accurate diagnostic tests that can determine whether asymptomatic individuals are actually uninfected, or instead are infected but just do not yet show detectable symptoms. PMID:27046030
Multistate outbreak of Norwalk-like virus gastroenteritis associated with a common caterer.
Anderson, A D; Garrett, V D; Sobel, J; Monroe, S S; Fankhauser, R L; Schwab, K J; Bresee, J S; Mead, P S; Higgins, C; Campana, J; Glass, R I
2001-12-01
In February 2000, an outbreak of gastroenteritis occurred among employees of a car dealership in New York. The same meal was also supplied to 52 dealerships nationwide, and 13 states reported illness at dealerships where the banquet was served. A retrospective cohort study was conducted to identify risk factors associated with the illness. Stool samples were collected to detect Norwalk-like virus, and sera were drawn and tested for immunoglobulin A antibodies to the outbreak strain. By univariate analysis, illness was significantly associated with consumption of any of four salads served at the banquet (relative risk = 3.8, 95% confidence interval: 2.5, 5.6). Norwalk-like virus was detected by reverse transcription-polymerase chain reaction assay in 32 of 59 stool samples from eight states. Nucleotide sequences of a 213-base pair fragment from 16 stool specimens collected from cases in eight states were identical, confirming a common source outbreak. Two of 15 workers at caterer A had elevated immunoglobulin A titers to an antigenically related Norwalk-like virus strain. This study highlights the value of molecular techniques to complement classic epidemiologic methods in outbreak investigations and underscores the critical role of food handlers in the spread of foodborne disease associated with Norwalk-like virus.
Jalava, Katri; Rintala, Hanna; Ollgren, Jukka; Maunula, Leena; Gomez-Alvarez, Vicente; Revez, Joana; Palander, Marja; Antikainen, Jenni; Kauppinen, Ari; Räsänen, Pia; Siponen, Sallamaari; Nyholm, Outi; Kyyhkynen, Aino; Hakkarainen, Sirpa; Merentie, Juhani; Pärnänen, Martti; Loginov, Raisa; Ryu, Hodon; Kuusi, Markku; Siitonen, Anja; Miettinen, Ilkka; Santo Domingo, Jorge W.; Hänninen, Marja-Liisa; Pitkänen, Tarja
2014-01-01
Failures in the drinking water distribution system cause gastrointestinal outbreaks with multiple pathogens. A water distribution pipe breakage caused a community-wide waterborne outbreak in Vuorela, Finland, July 2012. We investigated this outbreak with advanced epidemiological and microbiological methods. A total of 473/2931 inhabitants (16%) responded to a web-based questionnaire. Water and patient samples were subjected to analysis of multiple microbial targets, molecular typing and microbial community analysis. Spatial analysis on the water distribution network was done and we applied a spatial logistic regression model. The course of the illness was mild. Drinking untreated tap water from the defined outbreak area was significantly associated with illness (RR 5.6, 95% CI 1.9–16.4) increasing in a dose response manner. The closer a person lived to the water distribution breakage point, the higher the risk of becoming ill. Sapovirus, enterovirus, single Campylobacter jejuni and EHEC O157:H7 findings as well as virulence genes for EPEC, EAEC and EHEC pathogroups were detected by molecular or culture methods from the faecal samples of the patients. EPEC, EAEC and EHEC virulence genes and faecal indicator bacteria were also detected in water samples. Microbial community sequencing of contaminated tap water revealed abundance of Arcobacter species. The polyphasic approach improved the understanding of the source of the infections, and aided to define the extent and magnitude of this outbreak. PMID:25147923
Chen, Mingliang; Yao, Weilei; Wang, Xiaohong; Li, Yuefang; Chen, Min; Wang, Gangyi; Zhang, Xi; Pan, Hao; Hu, Jiayu; Zeng, Mei
2012-09-01
An unprecedented, large outbreak of childhood scarlet fever occurred in Shanghai between April and July 2011. Investigation of the epidemiology could enhance our understanding of the factors related to the outbreak. We retrospectively analyzed the demographic and seasonal characteristics of children with scarlet fever and the outcome. During the peak month of the 2011 outbreak, 45 GAS isolates recovered from pediatric patients and 13 (43.3%) GAS isolates recovered from 30 asymptomatic student contacts were characterized by emm typing, superantigen profiles, pulsed-field gel electrophoresis genotypes, mutilocus sequence typing and antimicrobial susceptibility. The 2011 outbreak of scarlet fever started in April and peaked in May and June. Boys outnumbered girls (65.1% versus 34.9%). Preschool and primary school children accounted for 96% of cases. No severe outcome was found. emm1, emm12 and emm75 were identified among 58 GAS isolates, and 53 (91.4%) isolates belonged to emm12, st36. Ten pulsed-field gel electrophoresis genotypes were identified among emm12 GAS isolates, 43 (81.1%) shared SPYS16.001 genotype and the remaining 7 genotypes detected were related to SPYS16.001 closely or possibly. No streptococcal pyrogenic exotoxin A and streptococcal pyrogenic exotoxin M were detected in 58 isolates. All emm12 GAS isolates were resistant to azithromycin and clindamycin. emm12 GAS strain caused the large 2011 outbreak of scarlet fever in Shanghai. Antibiotic resistance to macrolides and clindamycin in GAS is prevalent in Shanghai.
Bédard, Emilie; Laferrière, Céline; Charron, Dominique; Lalancette, Cindy; Renaud, Christian; Desmarais, Nadia; Déziel, Eric; Prévost, Michèle
2015-11-01
To perform a post-outbreak prospective study of the Pseudomonas aeruginosa contamination at the faucets (water, aerator and drain) by culture and quantitative polymerase chain reaction (qPCR) and to assess environmental factors influencing occurrence A 450-bed pediatric university hospital in Montreal, Canada Water, aerator swab, and drain swab samples were collected from faucets and analyzed by culture and qPCR for the post-outbreak investigation. Water microbial and physicochemical parameters were measured, and a detailed characterization of the sink environmental and design parameters was performed. The outbreak genotyping investigation identified drains and aerators as the source of infection. The implementation of corrective measures was effective, but post-outbreak sampling using qPCR revealed 50% positivity for P. aeruginosa remaining in the water compared with 7% by culture. P. aeruginosa was recovered in the water, the aerator, and the drain in 21% of sinks. Drain alignment vs the faucet and water microbial quality were significant factors associated with water positivity, whereas P. aeruginosa load in the water was an average of 2 log higher for faucets with a positive aerator. P. aeruginosa contamination in various components of sink environments was still detected several years after the resolution of an outbreak in a pediatric university hospital. Although contamination is often not detectable in water samples by culture, P. aeruginosa is present and can recover its culturability under favorable conditions. The importance of having clear maintenance protocols for water systems, including the drainage components, is highlighted.
Noller, Anna C; McEllistrem, M Catherine; Pacheco, Antonio G F; Boxrud, David J; Harrison, Lee H
2003-12-01
Escherichia coli O157:H7 is a major cause of food-borne illness in the United States. Outbreak detection involves traditional epidemiological methods and routine molecular subtyping by pulsed-field gel electrophoresis (PFGE). PFGE is labor-intensive, and the results are difficult to analyze and not easily transferable between laboratories. Multilocus variable-number tandem repeat (VNTR) analysis (MLVA) is a fast, portable method that analyzes multiple VNTR loci, which are areas of the bacterial genome that evolve quickly. Eighty isolates, including 21 isolates from five epidemiologically well-characterized outbreaks from Pennsylvania and Minnesota, were analyzed by PFGE and MLVA. Strains in PFGE clusters were defined as strains that differed by less than or equal to one band by using XbaI and the confirmatory enzyme SpeI. MLVA was performed by comparing the number of tandem repeats at seven loci. From 6 to 30 alleles were found at the seven loci, resulting in 64 MLVA types among the 80 isolates. MLVA correctly identified the isolates from all five outbreaks if only a single-locus variant was allowed. MLVA differentiated strains with unique PFGE types. Additionally, MLVA discriminated strains within PFGE-defined clusters that were not known to be part of an outbreak. In addition to being a simple and validated method for E. coli O157:H7 outbreak detection, MLVA appears to have a sensitivity equal to that of PFGE and a specificity superior to that of PFGE.
Lubogo, Mutaawe; Donewell, Bangure; Godbless, Lucas; Shabani, Sasita; Maeda, Justin; Temba, Herilinda; Malibiche, Theophil C; Berhanu, Naod
2015-01-01
The African Field Epidemiology Network (AFENET) is a public health network established in 2005 as a non-profit networking alliance of Field Epidemiology and Laboratory Training Programs (FELTPs) and Field Epidemiology Training Programs (FETPs) in Africa. AFENET is dedicated to supporting Ministries of Health in Africa build strong, effective and sustainable programs and capacity to improve public health systems by partnering with global public health experts. The Network's goal is to strengthen field epidemiology and public health laboratory capacity to contribute effectively to addressing epidemics and other major public health problems in Africa. The goal for the establishment of FETP and FELTP was and still is to produce highly competent multi-disciplinary public health professionals who would assume influential posts in the public health structures and tackle emerging and re-emerging communicable and non-communicable diseases. AFENET currently networks 12 FELTPs and FETPs in sub-Saharan Africa with operations in 20 countries. During the Ebola Virus Disease (EVD) outbreak in West Africa, African Union Support for the Ebola Outbreak in West Africa (ASEOWA) supported FETP graduates from Uganda, Zimbabwe, Ethiopia and Tanzania for the investigation and control of the EVD outbreak in Liberia. The graduates were posted in different counties in Liberia where they lead teams of other experts conduct EVD outbreak investigations, Infection Control and Prevention trainings among health workers and communities, Strengthening integrated disease surveillance, developing Standard Operating Procedures for infection control and case notification in the Liberian setting as well as building capacity of local surveillance officers' conduct outbreak investigation and contact tracing. The team was also responsible for EVD data management at the different Counties in Liberia. The FETP graduates have been instrumental in the earlier successes registered in various counties in Liberia in the control of the Ebola virus disease. Such efforts should be sustained by supporting local authorities develop strong health systems that are able to respond to epidemic of such magnitude in the near future.
Lubogo, Mutaawe; Donewell, Bangure; Godbless, Lucas; Shabani, Sasita; Maeda, Justin; Temba, Herilinda; Malibiche, Theophil C; Berhanu, Naod
2015-01-01
The African Field Epidemiology Network (AFENET) is a public health network established in 2005 as a non-profit networking alliance of Field Epidemiology and Laboratory Training Programs (FELTPs) and Field Epidemiology Training Programs (FETPs) in Africa. AFENET is dedicated to supporting Ministries of Health in Africa build strong, effective and sustainable programs and capacity to improve public health systems by partnering with global public health experts. The Network's goal is to strengthen field epidemiology and public health laboratory capacity to contribute effectively to addressing epidemics and other major public health problems in Africa. The goal for the establishment of FETP and FELTP was and still is to produce highly competent multi-disciplinary public health professionals who would assume influential posts in the public health structures and tackle emerging and re-emerging communicable and non-communicable diseases. AFENET currently networks 12 FELTPs and FETPs in sub-Saharan Africa with operations in 20 countries. During the Ebola Virus Disease (EVD) outbreak in West Africa, African Union Support for the Ebola Outbreak in West Africa (ASEOWA) supported FETP graduates from Uganda, Zimbabwe, Ethiopia and Tanzania for the investigation and control of the EVD outbreak in Liberia. The graduates were posted in different counties in Liberia where they lead teams of other experts conduct EVD outbreak investigations, Infection Control and Prevention trainings among health workers and communities, Strengthening integrated disease surveillance, developing Standard Operating Procedures for infection control and case notification in the Liberian setting as well as building capacity of local surveillance officers’ conduct outbreak investigation and contact tracing. The team was also responsible for EVD data management at the different Counties in Liberia. The FETP graduates have been instrumental in the earlier successes registered in various counties in Liberia in the control of the Ebola virus disease. Such efforts should be sustained by supporting local authorities develop strong health systems that are able to respond to epidemic of such magnitude in the near future. PMID:26779298
Qin, Meng; Dong, Xiao-Gen; Jing, Yan-Yan; Wei, Xiu-Xia; Wang, Zhao-E; Feng, Hui-Ru; Yu, Hong; Li, Jin-Song; Li, Jie
2016-09-01
Norovirus (NoV) is responsible for an estimated 90 % of all epidemic nonbacterial outbreaks of gastroenteritis worldwide. Waterborne outbreaks of NoV are commonly reported. A novel GII.17 NoV strain emerged as a major cause of gastroenteritis outbreaks in China during the winter of 2014/2015. During this time, an outbreak of gastroenteritis occurred at a hotel in a ski park in Hebei Province, China. Epidemiological investigations indicated that one water well, which had only recently been in use, was the probable source. GII.17 NoV was detected by real-time reverse-transcription polymerase chain reaction from samples taken from cases, from concentrated water samples from water well, and from the nearby sewage settling tank. Nucleotide sequences of NoV extracted from clinical and water specimens were genetically identical and had 99 % homology with Beijing/CHN/2015. All epidemiological data indicated that GII.17 NoV was responsible for this outbreak. This is the first reported laboratory-confirmed waterborne outbreak caused by GII.17 NoV genotype in China. Strengthening management of well drinking water and systematica monitoring of NoV is essential for preventing future outbreaks.
Internet and free press are associated with reduced lags in global outbreak reporting.
McAlarnen, Lindsey; Smith, Katherine; Brownstein, John S; Jerde, Christopher
2014-10-30
Global outbreak detection and reporting have generally improved for a variety of infectious diseases and geographic regions in recent decades. Nevertheless, lags in outbreak reporting remain a threat to the global human health and economy. In the time between first occurrence of a novel disease incident and public notification of an outbreak, infected individuals have a greater possibility of traveling and spreading the pathogen to other nations. Shortening outbreak reporting lags has the potential to improve global health by preventing local outbreaks from escalating into global epidemics. Reporting lags between the first record and the first public report of an event were calculated for 318 outbreaks occurring 1996-2009. The influence of freedom of the press, Internet usage, per capita health expenditure, and cell phone subscriptions, on the timeliness of outbreak reporting was evaluated. Freer presses and increasing Internet usage correlate with reduced time between the first record of an outbreak and the public report. Increasing Internet usage reduced the expected reporting lag from more than one month in nations without Internet users to one day in those where 75 of 100 people use the Internet. Advances in technology and the emergence of more open and free governments are associated with to improved global infectious disease surveillance.
Christner, Martin; Trusch, Maria; Rohde, Holger; Kwiatkowski, Marcel; Schlüter, Hartmut; Wolters, Manuel; Aepfelbacher, Martin; Hentschke, Moritz
2014-01-01
In 2011 northern Germany experienced a large outbreak of Shiga-Toxigenic Escherichia coli O104:H4. The large amount of samples sent to microbiology laboratories for epidemiological assessment highlighted the importance of fast and inexpensive typing procedures. We have therefore evaluated the applicability of a MALDI-TOF mass spectrometry based strategy for outbreak strain identification. Specific peaks in the outbreak strain's spectrum were identified by comparative analysis of archived pre-outbreak spectra that had been acquired for routine species-level identification. Proteins underlying these discriminatory peaks were identified by liquid chromatography tandem mass spectrometry and validated against publicly available databases. The resulting typing scheme was evaluated against PCR genotyping with 294 E. coli isolates from clinical samples collected during the outbreak. Comparative spectrum analysis revealed two characteristic peaks at m/z 6711 and m/z 10883. The underlying proteins were found to be of low prevalence among genome sequenced E. coli strains. Marker peak detection correctly classified 292 of 293 study isolates, including all 104 outbreak isolates. MALDI-TOF mass spectrometry allowed for reliable outbreak strain identification during a large outbreak of Shiga-Toxigenic E. coli. The applied typing strategy could probably be adapted to other typing tasks and might facilitate epidemiological surveys as part of the routine pathogen identification workflow.
Wang, Hua; Gill, Vikas S; Cheng, Chorng-Ming; Gonzalez-Escalona, Narjol; Irvin, Kari A; Zheng, Jie; Bell, Rebecca L; Jacobson, Andrew P; Hammack, Thomas S
2015-04-01
Foodborne outbreaks, involving pine nuts and peanut butter, illustrate the need to rapidly detect Salmonella in low moisture foods. However, the current Bacteriological Analytical Manual (BAM) culture method for Salmonella, using lactose broth (LB) as a pre enrichment medium, has not reliably supported real-time quantitative PCR (qPCR) assays for certain foods. We evaluated two qPCR assays in LB and four other pre enrichment media: buffered peptone water (BPW), modified BPW (mBPW), Universal Pre enrichment broth (UPB), and BAX(®) MP media to detect Salmonella in naturally-contaminated pine nuts (2011 outbreak). A four-way comparison among culture method, Pathatrix(®) Auto, VIDAS(®) Easy SLM, and qPCR was conducted. Automated DNA extraction techniques were compared with manual extraction methods (boiling or InstaGene™). There were no significant differences (P > 0.05) among the five pre enrichment media for pine nuts using the culture method. While both qPCR assays produced significantly (P ≤ 0.05) higher false negatives in 24 h pre enriched LB than in the other four media, they were as sensitive as the culture method in BPW, mBPW, UPB, and BAX media. The VIDAS Easy and qPCR were equivalent; Pathatrix was the least effective method. The Automatic PrepSEQ™ DNA extraction, using 1000 μL of pre enrichment, was as effective as manual extraction methods. Published by Elsevier Ltd.
2013-11-22
During January and February 2012, state and local public health agencies in West Virginia and Idaho, with assistance from facility staff members and CDC, investigated outbreaks of unexplained respiratory illness characterized by high proportions of lower respiratory tract infections (LRTIs) at two skilled nursing facilities (SNFs). Investigations were conducted to determine the extent and etiology of each outbreak and make recommendations to prevent further spread. During both outbreaks, influenza was initially suspected; however, human metapneumovirus (hMPV) was identified as the etiologic agent. Among 57 cases of respiratory illness from both facilities, 45 (79%) patients had evidence of LRTI, of whom 25 (56%) had radiologically confirmed pneumonia; five (9%) had evidence of upper respiratory tract infection (URTI), and seven (12%) could not be classified. Six patients (11%) died. These outbreaks demonstrate that hMPV, a recently described pathogen that would not have been detected without the use of molecular diagnostics in these outbreaks, is associated with severe LRTI and should be considered as a possible etiology of respiratory outbreaks in SNFs.
Ciupescu, Laurentiu-Mihai; Auvray, Frederic; Nicorescu, Isabela Madalina; Meheut, Thomas; Ciupescu, Veronica; Lardeux, Anne-Laure; Tanasuica, Rodica; Hennekinne, Jacques-Antoine
2018-06-05
To an increasing extent, molecular and genetic characterization is now used to investigate foodborne outbreaks. The aim of this study was to seek molecular links among coagulase-positive staphylococci (CPS) isolated from three recent food poisoning outbreaks in Romania using polymerase chain reaction and pulsed-field gel electrophoresis (PFGE) techniques. Nineteen CPS isolates were identified as Staphylococcus aureus by detection of the 23S rDNA gene. Among them, 15 carried at least one staphylococcal enterotoxin-encoding gene (se). The Calarași outbreak strains grouped in pulsotype 2 and were sed/sej/ser-positive, whereas the Arad outbreak strains clustered in pulsotype 17 and were either sed/seg/sei/sej/ser- or seg/sei-positive. The Pitești outbreak strains clustered in pulsotype 1 and, surprisingly, possessed only one enterotoxin gene, i.e. seh. Similar to other European countries, the seh gene has been identified with increasing frequency in Romanian outbreaks; this highlights the importance of considering the application of methods recommended for staphylococcal enterotoxin regulation in Europe.
2014-01-01
Background Bovine respiratory syncytial virus (BRSV) is one of the major pathogens involved in the bovine respiratory disease (BRD) complex. The seroprevalence to BRSV in Norwegian cattle herds is high, but its role in epidemics of respiratory disease is unclear. The aims of the study were to investigate the etiological role of BRSV and other respiratory viruses in epidemics of BRD and to perform phylogenetic analysis of Norwegian BRSV strains. Results BRSV infection was detected either serologically and/or virologically in 18 (86%) of 21 outbreaks and in most cases as a single viral agent. When serology indicated that bovine coronavirus and/or bovine parainfluenza virus 3 were present, the number of BRSV positive animals in the herd was always higher, supporting the view of BRSV as the main pathogen. Sequencing of the G gene of BRSV positive samples showed that the current circulating Norwegian BRSVs belong to genetic subgroup II, along with other North European isolates. One isolate from an outbreak in Norway in 1976 was also investigated. This strain formed a separate branch in subgroup II, clearly different from the current Scandinavian sequences. The currently circulating BRSV could be divided into two different strains that were present in the same geographical area at the same time. The sequence variations between the two strains were in an antigenic important part of the G protein. Conclusion The results demonstrated that BRSV is the most important etiological agent of epidemics of BRD in Norway and that it often acts as the only viral agent. The phylogenetic analysis of the Norwegian strains of BRSV and several previously published isolates supported the theory of geographical and temporal clustering of BRSV. PMID:24423030
Benschop, Kimberley S M; van der Avoort, Harrie G; Jusic, Edin; Vennema, Harry; van Binnendijk, Rob; Duizer, Erwin
2017-07-01
Polioviruses (PVs) are members of the genus Enterovirus In the Netherlands, the exclusion of PV circulation is based on clinical enterovirus (EV) surveillance (CEVS) of EV-positive cases and routine environmental EV surveillance (EEVS) conducted on sewage samples collected in the region of the Netherlands where vaccination coverage is low due to religious reasons. We compared the EEVS data to those of the CEVS to gain insight into the relevance of EEVS for poliovirus and nonpolio enterovirus surveillance. Following the polio outbreak in Syria, EEVS was performed at the primary refugee center in Ter Apel in the Netherlands, and data were compared to those of CEVS and EEVS. Furthermore, we assessed the feasibility of poliovirus detection by EEVS using measles virus detection in sewage during a measles outbreak as a proxy. Two Sabin-like PVs were found in routine EEVS, 11 Sabin-like PVs were detected in the CEVS, and one Sabin-like PV was found in the Ter Apel sewage. We observed significant differences between the three programs regarding which EVs were found. In 6 sewage samples collected during the measles outbreak in 2013, measles virus RNA was detected in regions where measles cases were identified. In conclusion, we detected PVs, nonpolio EVs, and measles virus in sewage and showed that environmental surveillance is useful for poliovirus detection in the Netherlands, where live oral poliovirus vaccine is not used and communities with lower vaccination coverage exist. EEVS led to the detection of EV types not seen in the CEVS, showing that EEVS is complementary to CEVS. IMPORTANCE We show that environmental enterovirus surveillance complements clinical enterovirus surveillance for poliovirus detection, or exclusion, and for nonpolio enterovirus surveillance. Even in the presence of adequate surveillance, only a very limited number of Sabin-like poliovirus strains were detected in a 10-year period, and no signs of transmission of oral polio vaccine (OPV) strains were found in a country using exclusively inactivated polio vaccine (IPV). Measles viruses can be detected during an outbreak in sewage samples collected and concentrated following procedures used for environmental enterovirus surveillance. Copyright © 2017 American Society for Microbiology.
Benschop, Kimberley S. M.; van der Avoort, Harrie G.; Jusic, Edin; Vennema, Harry; van Binnendijk, Rob
2017-01-01
ABSTRACT Polioviruses (PVs) are members of the genus Enterovirus. In the Netherlands, the exclusion of PV circulation is based on clinical enterovirus (EV) surveillance (CEVS) of EV-positive cases and routine environmental EV surveillance (EEVS) conducted on sewage samples collected in the region of the Netherlands where vaccination coverage is low due to religious reasons. We compared the EEVS data to those of the CEVS to gain insight into the relevance of EEVS for poliovirus and nonpolio enterovirus surveillance. Following the polio outbreak in Syria, EEVS was performed at the primary refugee center in Ter Apel in the Netherlands, and data were compared to those of CEVS and EEVS. Furthermore, we assessed the feasibility of poliovirus detection by EEVS using measles virus detection in sewage during a measles outbreak as a proxy. Two Sabin-like PVs were found in routine EEVS, 11 Sabin-like PVs were detected in the CEVS, and one Sabin-like PV was found in the Ter Apel sewage. We observed significant differences between the three programs regarding which EVs were found. In 6 sewage samples collected during the measles outbreak in 2013, measles virus RNA was detected in regions where measles cases were identified. In conclusion, we detected PVs, nonpolio EVs, and measles virus in sewage and showed that environmental surveillance is useful for poliovirus detection in the Netherlands, where live oral poliovirus vaccine is not used and communities with lower vaccination coverage exist. EEVS led to the detection of EV types not seen in the CEVS, showing that EEVS is complementary to CEVS. IMPORTANCE We show that environmental enterovirus surveillance complements clinical enterovirus surveillance for poliovirus detection, or exclusion, and for nonpolio enterovirus surveillance. Even in the presence of adequate surveillance, only a very limited number of Sabin-like poliovirus strains were detected in a 10-year period, and no signs of transmission of oral polio vaccine (OPV) strains were found in a country using exclusively inactivated polio vaccine (IPV). Measles viruses can be detected during an outbreak in sewage samples collected and concentrated following procedures used for environmental enterovirus surveillance. PMID:28432101
Cheng, V C C; Wu, A K L; Cheung, C H Y; Lau, S K P; Woo, P C Y; Chan, K H; Li, K S M; Ip, I K S; Dunn, E L W; Lee, R A; Yam, L Y C; Yuen, K Y
2007-12-01
Nosocomial outbreaks of infectious diseases in psychiatric facilities are not uncommon but the implementation of infection control measures is often difficult. Here, we report an outbreak of an acute respiratory illness in a psychiatric ward between 29 July and 20 August 2005 involving 31 patients. Human metapneumovirus was detected in seven (23%) patients by reverse transcription-polymerase chain reaction and nucleotide sequencing. A review of outbreak surveillance records showed that six nosocomial outbreaks occurred in the year 2005, of which four (67%) were confirmed or presumably related to a respiratory viral infection. Directly observed deliveries of alcohol hand rub 4-hourly during daytime to all psychiatric patients was instituted in December 2005. Only one nosocomial respiratory viral outbreak occurred in the following year. The total number of patients and staff involved in nosocomial outbreaks due to presumed or proven respiratory virus infections decreased significantly from 60 to six (P<0.001), whereas those due to all types of nosocomial outbreaks also decreased from 70 to 24 (P=0.004). Alcohol hand rub has been shown to have potent bactericidal and virucidal activity against a wide range of nosocomial pathogens. Regular use of directly observed alcohol hand rub may decrease the incidence and scale of nosocomial outbreaks due to enveloped respiratory viruses especially in mentally incapacitated patients.
Kamadjeu, Raoul; Gathenji, Caroline
2017-01-01
In April 2013, a case of wild polio virus (WPV) was detected in the Somalia capital Mogadishu. This inaugurated what is now referred to as the 2013-2014 Horn of Africa Polio outbreak with cases reported in Somalia, Kenya and Ethiopia. By the notification of the last polio case in August 2014, 223 cases of WPV had been reported in Somalia, Kenya and Ethiopia of which 199 in Somalia alone. The outbreak response required timely exchange of information between the outbreak response coordination unit (in Nairobi) and local staff located in multiple locations inside the country. The need to track and timely respond to information requests, to satisfy the information/data needs of polio partners and to track key outbreak response performance indicators dictated the need to urgently set up an online dashboard. The Somalia Polio Room dashboard provided a graphical display of the polio outbreak data to track progress and inform decision making. The system was designed using free and open sources components and seamlessly integrated existing polio surveillance data for real time monitoring of key outbreak response performance indicators. In this article, we describe the design and operation of an electronic dashboard for disease surveillance in an outbreak situation and used the lessons learned to propose key design considerations and functional requirements for online electronic dashboards for disease outbreak response. PMID:29296157
Kamadjeu, Raoul; Gathenji, Caroline
2017-01-01
In April 2013, a case of wild polio virus (WPV) was detected in the Somalia capital Mogadishu. This inaugurated what is now referred to as the 2013-2014 Horn of Africa Polio outbreak with cases reported in Somalia, Kenya and Ethiopia. By the notification of the last polio case in August 2014, 223 cases of WPV had been reported in Somalia, Kenya and Ethiopia of which 199 in Somalia alone. The outbreak response required timely exchange of information between the outbreak response coordination unit (in Nairobi) and local staff located in multiple locations inside the country. The need to track and timely respond to information requests, to satisfy the information/data needs of polio partners and to track key outbreak response performance indicators dictated the need to urgently set up an online dashboard. The Somalia Polio Room dashboard provided a graphical display of the polio outbreak data to track progress and inform decision making. The system was designed using free and open sources components and seamlessly integrated existing polio surveillance data for real time monitoring of key outbreak response performance indicators. In this article, we describe the design and operation of an electronic dashboard for disease surveillance in an outbreak situation and used the lessons learned to propose key design considerations and functional requirements for online electronic dashboards for disease outbreak response.
Dead or alive: animal sampling during Ebola hemorrhagic fever outbreaks in humans
Olson, Sarah H.; Reed, Patricia; Cameron, Kenneth N.; Ssebide, Benard J.; Johnson, Christine K.; Morse, Stephen S.; Karesh, William B.; Mazet, Jonna A. K.; Joly, Damien O.
2012-01-01
There are currently no widely accepted animal surveillance guidelines for human Ebola hemorrhagic fever (EHF) outbreak investigations to identify potential sources of Ebolavirus (EBOV) spillover into humans and other animals. Animal field surveillance during and following an outbreak has several purposes, from helping identify the specific animal source of a human case to guiding control activities by describing the spatial and temporal distribution of wild circulating EBOV, informing public health efforts, and contributing to broader EHF research questions. Since 1976, researchers have sampled over 10,000 individual vertebrates from areas associated with human EHF outbreaks and tested for EBOV or antibodies. Using field surveillance data associated with EHF outbreaks, this review provides guidance on animal sampling for resource-limited outbreak situations, target species, and in some cases which diagnostics should be prioritized to rapidly assess the presence of EBOV in animal reservoirs. In brief, EBOV detection was 32.7% (18/55) for carcasses (animals found dead) and 0.2% (13/5309) for live captured animals. Our review indicates that for the purposes of identifying potential sources of transmission from animals to humans and isolating suspected virus in an animal in outbreak situations, (1) surveillance of free-ranging non-human primate mortality and morbidity should be a priority, (2) any wildlife morbidity or mortality events should be investigated and may hold the most promise for locating virus or viral genome sequences, (3) surveillance of some bat species is worthwhile to isolate and detect evidence of exposure, and (4) morbidity, mortality, and serology studies of domestic animals should prioritize dogs and pigs and include testing for virus and previous exposure. PMID:22558004
Poovorawan, Kittiyod; Chattakul, Paiboon; Chattakul, Sirirat; Thongmee, Thanunrat; Theamboonlers, Apiradee; Komolmit, Piyawat; Poovorawan, Yong
2013-01-01
Introduction Acute hepatitis A is a worldwide public health problem especially in developing countries. Recently, a large, community-wide outbreak of hepatitis A occurred in the northeast part of Thailand. Methods Demographic and clinical data as well as blood samples were collected and analyzed from patients with acute hepatitis who attended the Buengkan Provincial Hospital from June to September 2012. About 1619 patients with clinical symptoms of hepatitis A visited the hospital during the outbreak which manifested in three waves. Blood samples were collected from 205 patients. Results One hundred and seventy eight patients had hepatitis A confirmed by the presence of anti-hepatitis A virus (HAV) IgM and/or HAV-RNA. The sensitivities for anti-HAV IgM and HAV-RNA were 95.5% (170/178) and 61.8% (110/178), respectively. When HAV-RNA was combined with anti-HAV IgM test, this increased the diagnostic yield by 7.2% (8/111) in the early phase of the acute infection (less than 5 days). Investigation of the molecular structure of the detected viruses indicated that all of the infections were caused by HAV genotype IA. There were no fatalities from this outbreak. Rapid detection, health education, sanitation campaigns, and vaccination offered on a voluntary basis have steadily reduced the number of infected patients and stopped the outbreak. Conclusion Occasionally a large-scale outbreak of HAV genotype IA can occur. A combination of HAV-RNA and anti-HAV IgM tests can increase the diagnostic yield during the early phase of the acute infection. Early diagnosis and preventive management campaigns can slow down and stop the outbreak. PMID:24392680
Health of whitebark pine forests after mountain pine beetle outbreaks
Sandra Kegley; John Schwandt; Ken Gibson; Dana Perkins
2011-01-01
Whitebark pine (Pinus albicaulis), a keystone high-elevation species, is currently at risk due to a combination of white pine blister rust (WPBR) (Cronartium ribicola), forest succession, and outbreaks of mountain pine beetle (MPB) (Dendroctonus ponderosae). While recent mortality is often quantified by aerial detection surveys (ADS) or ground surveys, little...
Molecular typing of Salmonella enterica serovar typhi.
Navarro, F; Llovet, T; Echeita, M A; Coll, P; Aladueña, A; Usera, M A; Prats, G
1996-01-01
The efficiencies of different tests for epidemiological markers--phage typing, ribotyping, IS200 typing, and pulsed-field gel electrophoresis (PFGE)--were evaluated for strains from sporadic cases of typhoid fever and a well-defined outbreak. Ribotyping and PFGE proved to be the most discriminating. Both detected two different patterns among outbreak-associated strains. PMID:8897193
Spectral evidence of early-stage spruce beetle infestation in Engelmann spruce
Adrianna C. Foster; Jonathan A. Walter; Herman H. Shugart; Jason Sibold; Jose Negron
2017-01-01
Spruce beetle (Dendroctonus rufipennis (Kirby)) outbreaks cause widespread mortality of Engelmann spruce (Picea engelmannii (Parry ex Engelm)) within the subalpine forests of the western United States. Early detection of infestations could allow forest managers to mitigate outbreaks or anticipate a response to tree mortality and the potential effects on ecosystem...
K. E. Mock; B. J. Bentz; E. M. O' Neill; J. P. Chong; J. Orwin; M. E. Pfrender
2007-01-01
The mountain pine beetle Dendroctonus ponderosae is a native species currently experiencing large-scale outbreaks in western North American pine forests. We sought to describe the pattern of genetic variation across the range of this species, to determine whether there were detectable genetic differences between D. ponderosae...
USDA-ARS?s Scientific Manuscript database
An outbreak of an invasive aphid was discovered damaging grain sorghum in Texas and neighboring states in 2013. It may be a new variant of sugarcane aphid, Melanaphis sacchari, that has a high preference for sorghum, or a very closely related species (M. sorghi). We designate it sorghum/sugarcane ...
Evaluation of Strategies to Control a Potential Outbreak of Foot-and-Mouth Disease in Sweden.
Dórea, Fernanda C; Nöremark, Maria; Widgren, Stefan; Frössling, Jenny; Boklund, Anette; Halasa, Tariq; Ståhl, Karl
2017-01-01
To minimize the potential consequences of an introduction of foot-and-mouth disease (FMD) in Europe, European Union (EU) member states are required to present a contingency plan. This study used a simulation model to study potential outbreak scenarios in Sweden and evaluate the best control strategies. The model was informed by the Swedish livestock structure using herd information from cattle, pig, and small ruminant holdings in the country. The contact structure was based on animal movement data and studies investigating the movements between farms of veterinarians, service trucks, and other farm visitors. All scenarios of outbreak control included depopulation of detected herds, 3 km protection and 10 km surveillance zones, movement tracing, and 3 days national standstill. The effect of availability of surveillance resources, i.e., number of field veterinarians per day, and timeliness of enforcement of interventions, was assessed. With the estimated currently available resources, an FMD outbreak in Sweden is expected to be controlled (i.e., last infected herd detected) within 3 weeks of detection in any evaluated scenario. The density of farms in the area where the epidemic started would have little impact on the time to control the outbreak, but spread in high density areas would require more surveillance resources, compared to areas of lower farm density. The use of vaccination did not result in a reduction in the expected number of infected herds. Preemptive depopulation was able to reduce the number of infected herds in extreme scenarios designed to test a combination of worst-case conditions of virus introduction and spread, but at the cost of doubling the number of herds culled. This likely resulted from a combination of the small outbreaks predicted by the spread model, and the high efficacy of the basic control measures evaluated, under the conditions of the Swedish livestock industry, and considering the assumed control resources available. The results indicate that the duration and extent of FMD outbreaks could be kept limited in Sweden using the EU standard control strategy and a 3 days national standstill.
Evaluation of Strategies to Control a Potential Outbreak of Foot-and-Mouth Disease in Sweden
Dórea, Fernanda C.; Nöremark, Maria; Widgren, Stefan; Frössling, Jenny; Boklund, Anette; Halasa, Tariq; Ståhl, Karl
2017-01-01
To minimize the potential consequences of an introduction of foot-and-mouth disease (FMD) in Europe, European Union (EU) member states are required to present a contingency plan. This study used a simulation model to study potential outbreak scenarios in Sweden and evaluate the best control strategies. The model was informed by the Swedish livestock structure using herd information from cattle, pig, and small ruminant holdings in the country. The contact structure was based on animal movement data and studies investigating the movements between farms of veterinarians, service trucks, and other farm visitors. All scenarios of outbreak control included depopulation of detected herds, 3 km protection and 10 km surveillance zones, movement tracing, and 3 days national standstill. The effect of availability of surveillance resources, i.e., number of field veterinarians per day, and timeliness of enforcement of interventions, was assessed. With the estimated currently available resources, an FMD outbreak in Sweden is expected to be controlled (i.e., last infected herd detected) within 3 weeks of detection in any evaluated scenario. The density of farms in the area where the epidemic started would have little impact on the time to control the outbreak, but spread in high density areas would require more surveillance resources, compared to areas of lower farm density. The use of vaccination did not result in a reduction in the expected number of infected herds. Preemptive depopulation was able to reduce the number of infected herds in extreme scenarios designed to test a combination of worst-case conditions of virus introduction and spread, but at the cost of doubling the number of herds culled. This likely resulted from a combination of the small outbreaks predicted by the spread model, and the high efficacy of the basic control measures evaluated, under the conditions of the Swedish livestock industry, and considering the assumed control resources available. The results indicate that the duration and extent of FMD outbreaks could be kept limited in Sweden using the EU standard control strategy and a 3 days national standstill. PMID:28791298
Yang, F; Guo, G Z; Chen, J Q; Ma, H W; Liu, T; Huang, D N; Yao, C H; Zhang, R L; Xue, C F; Zhang, L
2014-02-01
A suspected dengue fever outbreak occurred in 2010 at a solitary construction site in Shenzhen city, China. To investigate this epidemic, we used serological, molecular biological, and bioinformatics techniques. Of nine serum samples from suspected patients, we detected seven positive for dengue virus (DENV) antibodies, eight for DENV-1 RNA, and three containing live viruses. The isolated virus, SZ1029 strain, was sequenced and confirmed as DENV-1, showing the highest E-gene homology to D1/Malaysia/36000/05 and SG(EHI)DED142808 strains recently reported in Southeast Asia. Further phylogenetic tree analysis confirmed their close relationship. At the epidemic site, we also detected 14 asymptomatic co-workers (out of 291) positive for DENV antibody, and DENV-1-positive mosquitoes. Thus, we concluded that DENV-1 caused the first local dengue fever outbreak in Shenzhen. Because no imported case was identified, the molecular fingerprints of the SZ1029 strain suggest this outbreak may be due to vertical transmission imported from Southeast Asia.
Cheng, Karen Elizabeth; Crary, David J; Ray, Jaideep; Safta, Cosmin
2013-01-01
Objective We discuss the use of structural models for the analysis of biosurveillance related data. Methods and results Using a combination of real and simulated data, we have constructed a data set that represents a plausible time series resulting from surveillance of a large scale bioterrorist anthrax attack in Miami. We discuss the performance of anomaly detection with structural models for these data using receiver operating characteristic (ROC) and activity monitoring operating characteristic (AMOC) analysis. In addition, we show that these techniques provide a method for predicting the level of the outbreak valid for approximately 2 weeks, post-alarm. Conclusions Structural models provide an effective tool for the analysis of biosurveillance data, in particular for time series with noisy, non-stationary background and missing data. PMID:23037798
Oren, I; Zuckerman, T; Avivi, I; Finkelstein, R; Yigla, M; Rowe, J M
2002-08-01
A nosocomial outbreak of pneumonia caused by Legionella pneumophila serogroup 3 occurred in four patients following hematopoietic stem cell transplantation (HSCT) in a new bone marrow transplantation (BMT) unit during a 2 week period. The causative organism was recovered from the water supply system to the same unit just before the outbreak. Nineteen other BMT patients were hospitalized in the same unit at the same time, giving a frequency of proven infection of 4/23 = 17%. Immediately after recognition of the outbreak, use of tap water was forbidden, humidifiers were disconnected, and ciprofloxacin prophylaxis was started for all patients in the unit, until decontamination of the water was achieved. No other cases were detected. In conclusion, contamination of the hospital water supply system with legionella carries a high risk for legionella pneumonia among BMT patients. Early recognition of the outbreak, immediate restrictions of water use, antibiotic prophylaxis for all non-infected patients, and water decontamination, successfully terminated the outbreak.
Epidemiological and molecular analysis of a waterborne outbreak of norovirus GII.4.
Zhou, X; Li, H; Sun, L; Mo, Y; Chen, S; Wu, X; Liang, J; Zheng, H; Ke, C; Varma, J K; Klena, J D; Chen, Q; Zou, L; Yang, X
2012-12-01
Contaminated water is one of the main sources of norovirus (NoV) gastroenteritis outbreaks globally. Waterborne NoV outbreaks are infrequently attributed to GII.4 NoV. In September 2009, a NoV outbreak affected a small school in Guangdong Province, China. Epidemiological investigations indicated that household use water, supplied by a well, was the probable source (relative risk 1·9). NoV nucleic acid material in concentrated well-water samples was detected using real-time RT-PCR. Nucleotide sequences of NoV extracted from diarrhoea and well-water specimens were identical and had the greatest sequence identity to corresponding sequences from the epidemic strain GII.4-2006b. Our report documents the first laboratory-confirmed waterborne outbreak caused by GII.4 NoV genotype in China. Our investigations indicate that well water, intended exclusively for household use but not for consumption, caused this outbreak. The results of this report serve as a reminder that private well water intended for household use should be tested for NoV.
Du, Pengcheng; Zheng, Han; Zhou, Jieping; Lan, Ruiting; Ye, Changyun; Jing, Huaiqi; Jin, Dong; Cui, Zhigang; Bai, Xuemei; Liang, Jianming; Liu, Jiantao; Xu, Lei; Zhang, Wen; Chen, Chen
2017-01-01
Streptococcus suis sequence type 7 emerged and caused 2 of the largest human infection outbreaks in China in 1998 and 2005. To determine the major risk factors and source of the infections, we analyzed whole genomes of 95 outbreak-associated isolates, identified 160 single nucleotide polymorphisms, and classified them into 6 clades. Molecular clock analysis revealed that clade 1 (responsible for the 1998 outbreak) emerged in October 1997. Clades 2–6 (responsible for the 2005 outbreak) emerged separately during February 2002–August 2004. A total of 41 lineages of S. suis emerged by the end of 2004 and rapidly expanded to 68 genome types through single base mutations when the outbreak occurred in June 2005. We identified 32 identical isolates and classified them into 8 groups, which were distributed in a large geographic area with no transmission link. These findings suggest that persons were infected in parallel in respective geographic sites. PMID:27997331
[Outbreaks of viral hepatitis E in the Czech Republic?].
Trmal, Josef; Pavlík, Ivo; Vasícková, Petra; Matejícková, Ladislava; Simůnková, Lenka; Luks, Stanislav; Pazderková, Jana
2012-05-01
Until recently, viral hepatitis E (VHE) has typically been an imported infection, related to travel to developing countries. A number of travel-unrelated VHE cases currently diagnosed in the Czech Republic. Outcomes of the epidemiological investigations of two VHE outbreaks associated with the consumption of pork and pork products at pig-slaughtering feasts are presented. Thirteen cases have been reported in the first outbreak and eight cases in the second outbreak. The epidemiological investigations are described and the experience gained in analysing suspected biological specimens is presented. The source of infection has not been identified in the first outbreak while in the other one, a link between human cases and infection in farm pigs was revealed for the first time. Although the epidemiological investigation may not always lead to the detection of the VHE source, it must be conducted in any outbreak and can only be successful when done in cooperation of the public health authorities with the veterinary health agency.
Serratia marcescens outbreak due to contaminated 2% aqueous chlorhexidine.
de Frutos, Mónica; López-Urrutia, Luis; Domínguez-Gil, Marta; Arias, Marta; Muñoz-Bellido, Juan Luis; Eiros, José María; Ramos, Carmen
2017-12-01
An outbreak of Serratia marcescens infections outbreak is described, as well as the epidemiological study that linked the outbreak to the use of 2% aqueous chlorhexidine antiseptic. In late November 2014 an increasing incidence of S. marcescens isolates was detected in patients treated in the emergency department. It was considered a possible outbreak, and an epidemiological investigation was started. S. marcescens was isolated in 23 samples from 16 patients and in all new bottles of two lots of 2% aqueous chlorhexidine. The contaminated disinfectant was withdrawn, and the Spanish Drugs Agency was alerted (COS 2/2014). The epidemiological study showed that strains isolated from clinical samples and from chlorhexidine belonged to the same clone. No further isolates were obtained once the disinfectant was withdrawn. The suspicion of an outbreak and the epidemiological study were essential to control the incidence. Copyright © 2016 Elsevier España, S.L.U. and Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.
Gymoese, Pernille; Sørensen, Gitte; Litrup, Eva; Olsen, John Elmerdal; Nielsen, Eva Møller
2017-01-01
Whole-genome sequencing is rapidly replacing current molecular typing methods for surveillance purposes. Our study evaluates core-genome single-nucleotide polymorphism analysis for outbreak detection and linking of sources of Salmonella enterica serovar Typhimurium and its monophasic variants during a 7-month surveillance period in Denmark. We reanalyzed and defined 8 previously characterized outbreaks from the phylogenetic relatedness of the isolates, epidemiologic data, and food traceback investigations. All outbreaks were identified, and we were able to exclude unrelated and include additional related human cases. We were furthermore able to link possible food and veterinary sources to the outbreaks. Isolates clustered according to sequence types (STs) 19, 34, and 36. Our study shows that core-genome single-nucleotide polymorphism analysis is suitable for surveillance and outbreak investigation for Salmonella Typhimurium (ST19 and ST36), but whole genome–wide analysis may be required for the tight genetic clone of monophasic variants (ST34). PMID:28930002
Orosz, László; Gáspár, Gábor; Rózsa, Ágnes; Rákos, Nóra; Sziveri, Szilárd; Bosnyákovits, Tünde
2018-02-28
Although the prevalence of wild-type measles virus infection has decreased by >90% in Europe, the disease is still not eliminated and has even reemerged with recurrent outbreaks in different countries, including Romania and Italy. Minor outbreaks of Romanian origin were reported from Hungary as well. In Romania, an outbreak has been ongoing since February 2016. As of October 2017, 9,670 measles cases and 35 deaths were registered in the country. The three most affected counties are located next to the Hungarian border. In Italy, until the end of August 2017, 4,477 cases were reported to the surveillance system. The outbreak affected most of the Italian administrative regions. Until October 2017, three minor measles outbreaks were also detected in Hungary. All of these outbreaks were derived from Romanian cases. Although in these countries, there are vaccination programs running, the spread of the disease raises the possibility of secondary vaccine failure.
Automated real time constant-specificity surveillance for disease outbreaks.
Wieland, Shannon C; Brownstein, John S; Berger, Bonnie; Mandl, Kenneth D
2007-06-13
For real time surveillance, detection of abnormal disease patterns is based on a difference between patterns observed, and those predicted by models of historical data. The usefulness of outbreak detection strategies depends on their specificity; the false alarm rate affects the interpretation of alarms. We evaluate the specificity of five traditional models: autoregressive, Serfling, trimmed seasonal, wavelet-based, and generalized linear. We apply each to 12 years of emergency department visits for respiratory infection syndromes at a pediatric hospital, finding that the specificity of the five models was almost always a non-constant function of the day of the week, month, and year of the study (p < 0.05). We develop an outbreak detection method, called the expectation-variance model, based on generalized additive modeling to achieve a constant specificity by accounting for not only the expected number of visits, but also the variance of the number of visits. The expectation-variance model achieves constant specificity on all three time scales, as well as earlier detection and improved sensitivity compared to traditional methods in most circumstances. Modeling the variance of visit patterns enables real-time detection with known, constant specificity at all times. With constant specificity, public health practitioners can better interpret the alarms and better evaluate the cost-effectiveness of surveillance systems.
Allen, Heather A.
2015-01-01
The merits of One Health have been thoroughly described in the literature, but how One Health operates in the United States federal system of government is rarely discussed or analyzed. Through a comparative case-study approach, this research explores how federalism, bureaucratic behavior, and institutional design in the United States may influence zoonotic disease outbreak detection and reporting, a key One Health activity. Using theoretical and empirical literature, as well as a survey/interview instrument for individuals directly involved in a past zoonotic disease outbreak, the impacts of governance are discussed. As predicted in the theoretical literature, empirical findings suggest that federalism, institutional design, and bureaucracy may play a role in facilitating or impeding zoonotic disease outbreak detection and reporting. Regulatory differences across states as well as compartmentalization of information within agencies may impede disease detection. However, the impact may not always be negative: bureaucracies can also be adaptive; federalism allows states important opportunities for innovation. While acknowledging there are many other factors that also matter in zoonotic disease detection and reporting, this research is one of the first attempts to raise awareness in the literature and stimulate discussion on the intersection of governance and One Health. PMID:29061932
Sharp, Tyler M; Mackay, Andrew J; Santiago, Gilberto A; Hunsperger, Elizabeth; Nilles, Eric J; Perez-Padilla, Janice; Tikomaidraubuta, Kinisalote S; Colon, Candimar; Amador, Manuel; Chen, Tai-Ho; Lalita, Paul; Muñoz-Jordán, Jorge L; Barrera, Roberto; Langidrik, Justina; Tomashek, Kay M
2014-01-01
Dengue is a potentially fatal acute febrile illness caused by four mosquito-transmitted dengue viruses (DENV-1-4). Although dengue outbreaks regularly occur in many regions of the Pacific, little is known about dengue in the Republic of the Marshall Islands (RMI). To better understand dengue in RMI, we investigated an explosive outbreak that began in October 2011. Suspected cases were reported to the Ministry of Health, serum specimens were tested with a dengue rapid diagnostic test (RDT), and confirmatory testing was performed using RT-PCR and IgM ELISA. Laboratory-positive cases were defined by detection of DENV nonstructural protein 1 by RDT, DENV nucleic acid by RT-PCR, or anti-DENV IgM antibody by RDT or ELISA. Secondary infection was defined by detection of anti-DENV IgG antibody by ELISA in a laboratory-positive acute specimen. During the four months of the outbreak, 1,603 suspected dengue cases (3% of the RMI population) were reported. Of 867 (54%) laboratory-positive cases, 209 (24%) had dengue with warning signs, six (0.7%) had severe dengue, and none died. Dengue incidence was highest in residents of Majuro and individuals aged 10-29 years, and ∼95% of dengue cases were experiencing secondary infection. Only DENV-4 was detected by RT-PCR, which phylogenetic analysis demonstrated was most closely related to a virus previously identified in Southeast Asia. Cases of vertical DENV transmission, and DENV/Salmonella Typhi and DENV/Mycobacterium leprae co-infection were identified. Entomological surveys implicated water storage containers and discarded tires as the most important development sites for Aedes aegypti and Ae. albopictus, respectively. Although this is the first documented dengue outbreak in RMI, the age groups of cases and high prevalence of secondary infection demonstrate prior DENV circulation. Dengue surveillance should continue to be strengthened in RMI and throughout the Pacific to identify and rapidly respond to future outbreaks.
Sharp, Tyler M.; Mackay, Andrew J.; Santiago, Gilberto A.; Hunsperger, Elizabeth; Nilles, Eric J.; Perez-Padilla, Janice; Tikomaidraubuta, Kinisalote S.; Colon, Candimar; Amador, Manuel; Chen, Tai-Ho; Lalita, Paul; Muñoz-Jordán, Jorge L.; Barrera, Roberto; Langidrik, Justina; Tomashek, Kay M.
2014-01-01
Dengue is a potentially fatal acute febrile illness caused by four mosquito-transmitted dengue viruses (DENV-1–4). Although dengue outbreaks regularly occur in many regions of the Pacific, little is known about dengue in the Republic of the Marshall Islands (RMI). To better understand dengue in RMI, we investigated an explosive outbreak that began in October 2011. Suspected cases were reported to the Ministry of Health, serum specimens were tested with a dengue rapid diagnostic test (RDT), and confirmatory testing was performed using RT-PCR and IgM ELISA. Laboratory-positive cases were defined by detection of DENV nonstructural protein 1 by RDT, DENV nucleic acid by RT-PCR, or anti-DENV IgM antibody by RDT or ELISA. Secondary infection was defined by detection of anti-DENV IgG antibody by ELISA in a laboratory-positive acute specimen. During the four months of the outbreak, 1,603 suspected dengue cases (3% of the RMI population) were reported. Of 867 (54%) laboratory-positive cases, 209 (24%) had dengue with warning signs, six (0.7%) had severe dengue, and none died. Dengue incidence was highest in residents of Majuro and individuals aged 10–29 years, and ∼95% of dengue cases were experiencing secondary infection. Only DENV-4 was detected by RT-PCR, which phylogenetic analysis demonstrated was most closely related to a virus previously identified in Southeast Asia. Cases of vertical DENV transmission, and DENV/Salmonella Typhi and DENV/Mycobacterium leprae co-infection were identified. Entomological surveys implicated water storage containers and discarded tires as the most important development sites for Aedes aegypti and Ae. albopictus, respectively. Although this is the first documented dengue outbreak in RMI, the age groups of cases and high prevalence of secondary infection demonstrate prior DENV circulation. Dengue surveillance should continue to be strengthened in RMI and throughout the Pacific to identify and rapidly respond to future outbreaks. PMID:25268134
Using Combined Diagnostic Test Results to Hindcast Trends of Infection from Cross-Sectional Data
Rydevik, Gustaf; Innocent, Giles T.; Marion, Glenn; White, Piran C. L.; Billinis, Charalambos; Barrow, Paul; Mertens, Peter P. C.; Gavier-Widén, Dolores; Hutchings, Michael R.
2016-01-01
Infectious disease surveillance is key to limiting the consequences from infectious pathogens and maintaining animal and public health. Following the detection of a disease outbreak, a response in proportion to the severity of the outbreak is required. It is thus critical to obtain accurate information concerning the origin of the outbreak and its forward trajectory. However, there is often a lack of situational awareness that may lead to over- or under-reaction. There is a widening range of tests available for detecting pathogens, with typically different temporal characteristics, e.g. in terms of when peak test response occurs relative to time of exposure. We have developed a statistical framework that combines response level data from multiple diagnostic tests and is able to ‘hindcast’ (infer the historical trend of) an infectious disease epidemic. Assuming diagnostic test data from a cross-sectional sample of individuals infected with a pathogen during an outbreak, we use a Bayesian Markov Chain Monte Carlo (MCMC) approach to estimate time of exposure, and the overall epidemic trend in the population prior to the time of sampling. We evaluate the performance of this statistical framework on simulated data from epidemic trend curves and show that we can recover the parameter values of those trends. We also apply the framework to epidemic trend curves taken from two historical outbreaks: a bluetongue outbreak in cattle, and a whooping cough outbreak in humans. Together, these results show that hindcasting can estimate the time since infection for individuals and provide accurate estimates of epidemic trends, and can be used to distinguish whether an outbreak is increasing or past its peak. We conclude that if temporal characteristics of diagnostics are known, it is possible to recover epidemic trends of both human and animal pathogens from cross-sectional data collected at a single point in time. PMID:27384712
Mayr, Astrid; Hinterberger, Guido; Lorenz, Ingo H; Kreidl, Peter; Mutschlechner, Wolfgang; Lass-Flörl, Cornelia
2017-04-01
An increase of extensively drug-resistant Pseudomonas aeruginosa (XDR-PA) in various clinical specimens among intensive care unit patients (n = 7) initiated an outbreak investigation consisting of patient data analyses, control of adherence to infection control guidelines, microbiologic surveys, and molecular-based studies. XDR-PA was detected in a jointly used aroma-oil nursing bottle for aromatherapy. We implemented the restriction of oil sharing among patients. Hence, the outbreak was controlled successfully. Copyright © 2017 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.
Management of rodent viral disease outbreaks: one institutions (r)evolution.
Smith, Abigail L
2010-01-01
At first blush, an outbreak of mouse hepatitis virus or epizootic diarrhea of infant mice virus in a research colony of laboratory mice may not seem like a disaster. However, irrespective of magnitude, such an outbreak at an academic institution is disruptive for researchers at all levels. It can be a disaster for the graduate student who may have just a few experiments to finish before writing the thesis or for the postdoctoral fellow who is in the lab for only 1 or 2 years. Infectious disease outbreaks also limit the ability of principal investigators to share their animals with collaborators at their home institution as well as with those at extramural sites, thereby thwarting the expectation that research materials supported by federal funds will be made readily available to colleagues. This article traces the evolution of a change in culture at a large, well-funded academic institution with over 1,800 active IACUC protocols, more than 1,000 of which include mice. During a period of less than 5 years, the institution evolved from virtual paralysis in the face of such outbreaks to the implementation of policies and practices that enable effective outbreak management and the timely resumption of research functionality. This evolution required not only support from the highest levels of leadership in the university and its school of medicine but also a huge outlay of financial resources.
Evaluation of a national pharmacy‐based syndromic surveillance system
Muchaal, PK; Parker, S; Meganath, K; Landry, L; Aramini, J
2015-01-01
Background Traditional public health surveillance provides accurate information but is typically not timely. New early warning systems leveraging timely electronic data are emerging, but the public health value of such systems is still largely unknown. Objective To assess the timeliness and accuracy of pharmacy sales data for both respiratory and gastrointestinal infections and to determine its utility in supporting the surveillance of gastrointestinal illness. Methods To assess timeliness, a prospective and retrospective analysis of data feeds was used to compare the chronological characteristics of each data stream. To assess accuracy, Ontario antiviral prescriptions were compared to confirmed cases of influenza and cases of influenza-like-illness (ILI) from August 2009 to January 2015 and Nova Scotia sales of respiratory over-the-counter products (OTC) were compared to laboratory reports of respiratory pathogen detections from January 2014 to March 2015. Enteric outbreak data (2011-2014) from Nova Scotia were compared to sales of gastrointestinal products for the same time period. To assess utility, pharmacy sales of gastrointestinal products were monitored across Canada to detect unusual increases and reports were disseminated to the provinces and territories once a week between December 2014 and March 2015 and then a follow-up evaluation survey of stakeholders was conducted. Results Ontario prescriptions of antivirals between 2009 and 2015 correlated closely with the onset dates and magnitude of confirmed influenza cases. Nova Scotia sales of respiratory OTC products correlated with increases in non-influenza respiratory pathogens in the community. There were no definitive correlations identified between the occurrence of enteric outbreaks and the sales of gastrointestinal OTCs in Nova Scotia. Evaluation of national monitoring showed no significant increases in sales of gastrointestinal products that could be linked to outbreaks that included more than one province or territory. Conclusion Monitoring of pharmacy-based drug prescriptions and OTC sales can provide a timely and accurate complement to traditional respiratory public health surveillance activities but initial evaluation did not show that tracking gastrointestinal-related OTCs were of value in identifying an enteric disease outbreak in more than one province or territory during the study period. PMID:29769953
Jaakkonen, A; Salmenlinna, S; Rimhanen-Finne, R; Lundström, H; Heinikainen, S; Hakkinen, M; Hallanvuo, S
2017-09-01
Shiga toxin-producing, sorbitol-fermenting Escherichia coli O157 (SF O157) has emerged as a cause of severe human illness. Despite frequent human findings, its transmission routes and reservoirs remain largely unknown. Foodborne transmission and reservoir in cattle have been suspected, but with limited supporting evidence. This study describes the outbreak of SF O157 that occurred in Finland in 2012. The outbreak originated from a recreational farm selling unpasteurized milk, as revealed by epidemiologic and microbiological investigations, and involved six hospitalized children and two asymptomatic adults with culture-confirmed infection. An identical strain of SF O157 was isolated from patients, cattle and the farm environment, and epidemiologic analysis suggested unpasteurized milk as the vehicle of transmission. This study reports the first milkborne outbreak of SF O157, provides supporting evidence of cattle as a reservoir and highlights the health risks related to the consumption of unpasteurized milk. © 2017 The Authors. Zoonoses and Public Health Published by Blackwell Verlag GmbH.
Roisin, S; Gaudin, C; De Mendonça, R; Bellon, J; Van Vaerenbergh, K; De Bruyne, K; Byl, B; Pouseele, H; Denis, O; Supply, P
2016-06-01
We used a two-step whole genome sequencing analysis for resolving two concurrent outbreaks in two neonatal services in Belgium, caused by exfoliative toxin A-encoding-gene-positive (eta+) methicillin-susceptible Staphylococcus aureus with an otherwise sporadic spa-type t209 (ST-109). Outbreak A involved 19 neonates and one healthcare worker in a Brussels hospital from May 2011 to October 2013. After a first episode interrupted by decolonization procedures applied over 7 months, the outbreak resumed concomitantly with the onset of outbreak B in a hospital in Asse, comprising 11 neonates and one healthcare worker from mid-2012 to January 2013. Pan-genome multilocus sequence typing, defined on the basis of 42 core and accessory reference genomes, and single-nucleotide polymorphisms mapped on an outbreak-specific de novo assembly were used to compare 28 available outbreak isolates and 19 eta+/spa-type t209 isolates identified by routine or nationwide surveillance. Pan-genome multilocus sequence typing showed that the outbreaks were caused by independent clones not closely related to any of the surveillance isolates. Isolates from only ten cases with overlapping stays in outbreak A, including four pairs of twins, showed no or only a single nucleotide polymorphism variation, indicating limited sequential transmission. Detection of larger genomic variation, even from the start of the outbreak, pointed to sporadic seeding from a pre-existing exogenous source, which persisted throughout the whole course of outbreak A. Whole genome sequencing analysis can provide unique fine-tuned insights into transmission pathways of complex outbreaks even at their inception, which, with timely use, could valuably guide efforts for early source identification. Copyright © 2016 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.
Dengue Contingency Planning: From Research to Policy and Practice.
Runge-Ranzinger, Silvia; Kroeger, Axel; Olliaro, Piero; McCall, Philip J; Sánchez Tejeda, Gustavo; Lloyd, Linda S; Hakim, Lokman; Bowman, Leigh R; Horstick, Olaf; Coelho, Giovanini
2016-09-01
Dengue is an increasingly incident disease across many parts of the world. In response, an evidence-based handbook to translate research into policy and practice was developed. This handbook facilitates contingency planning as well as the development and use of early warning and response systems for dengue fever epidemics, by identifying decision-making processes that contribute to the success or failure of dengue surveillance, as well as triggers that initiate effective responses to incipient outbreaks. Available evidence was evaluated using a step-wise process that included systematic literature reviews, policymaker and stakeholder interviews, a study to assess dengue contingency planning and outbreak management in 10 countries, and a retrospective logistic regression analysis to identify alarm signals for an outbreak warning system using datasets from five dengue endemic countries. Best practices for managing a dengue outbreak are provided for key elements of a dengue contingency plan including timely contingency planning, the importance of a detailed, context-specific dengue contingency plan that clearly distinguishes between routine and outbreak interventions, surveillance systems for outbreak preparedness, outbreak definitions, alert algorithms, managerial capacity, vector control capacity, and clinical management of large caseloads. Additionally, a computer-assisted early warning system, which enables countries to identify and respond to context-specific variables that predict forthcoming dengue outbreaks, has been developed. Most countries do not have comprehensive, detailed contingency plans for dengue outbreaks. Countries tend to rely on intensified vector control as their outbreak response, with minimal focus on integrated management of clinical care, epidemiological, laboratory and vector surveillance, and risk communication. The Technical Handbook for Surveillance, Dengue Outbreak Prediction/ Detection and Outbreak Response seeks to provide countries with evidence-based best practices to justify the declaration of an outbreak and the mobilization of the resources required to implement an effective dengue contingency plan.
Streptococcus pyogenes outbreak in a long-term care facility.
Harkness, G A; Bentley, D W; Mottley, M; Lee, J
1992-06-01
Although outbreaks involving Streptococcus pyogenes have been uncommon among the elderly population, recent reports suggest that this organism is an important nosocomial pathogen among institutionalized older patients and carries significant morbidity and mortality. An outbreak of S. pyogenes, type M12, T12, occurred in a large long-term care institution serving the ill and chronically disabled. The outbreak involved 14 residents of the intermediate care facility and lasted for 4 months. A prospective epidemiologic investigation was initiated at the onset of the outbreak. Pertinent clinical and demographic information regarding both residents and personnel was obtained by interview, review of medical and surveillance records, and examination of patients for lesions. Cultures were obtained within 24 hours of symptom onset from those with characteristic clinical symptoms. Unpaired convalescent sera were tested for group A streptococcal extracellular antigens by a rapid hemagglutination slide test. Control measures included active surveillance of residents and staff for suspicious clinical syndromes, transfer of high-risk patients, elimination of a common seating area, and improved handwashing and hygiene measures. The attack rate was 7.5%, with 64.3% of these patients residing on one unit. S. pyogenes was isolated from eight residents, 5 residents had a characteristic syndrome and an elevated streptozyme hemagglutination titer of 400, and 1 resident died within hours of having cellulitis of the groin. Clinical syndromes included cellulitis, pharyngitis, bronchitis, pneumonia, and septicemia. Seven residents required acute care; two residents died within 3 weeks of the onset, yielding a case fatality rate of 14.3%. The major means of transmission appeared to be direct contact between residents, although transmission from an infected staff member may have accounted for some cases. The hypothesis of long-term colonization was supported by the extended times between infections. The severity of illness and the apparent transmission through direct contact between residents warrants (1) early detection of infected lesions, (2) recognition of invasive illness, (3) prompt effective treatment, and (4) surveillance for S. pyogenes infections among residents and personnel.
Zhuge, Jian; Vail, Eric; Bush, Jeffrey L; Singelakis, Lauren; Huang, Weihua; Nolan, Sheila M; Haas, Janet P; Engel, Helen; Della Posta, Millicent; Yoon, Esther C; Fallon, John T; Wang, Guiqing
2015-06-01
An outbreak of severe respiratory illness associated with enterovirus D68 (EV-D68) infection was reported in mid-August 2014 in the United States. In this study, we evaluated the diagnostic utility of an EV-D68-specific real-time reverse transcription-PCR (rRT-PCR) that was recently developed by the Centers for Disease Control and Prevention in clinical samples. Nasopharyngeal (NP) swab specimens from patients in a recent outbreak of respiratory illness in the lower Hudson Valley, New York State, were collected and examined for the presence of human rhinovirus or enterovirus using the FilmArray Respiratory Panel (RP) assay. Samples positive by RP were assessed using EV-D68 rRT-PCR, and the data were compared to results from sequencing analysis of partial VP1 and 5' untranslated region (5'-UTR) sequences of the EV genome. A total of 285 RP-positive NP specimens (260 from the 2014 outbreak and 25 from 2013) were analyzed by rRT-PCR; EV-D68 was detected in 74 of 285 (26.0%) specimens examined. Data for comparisons between rRT-PCR and sequencing analysis were obtained from 194 NP specimens. EV-D68 detection was confirmed by sequencing analysis in 71 of 74 positive and in 1 of 120 randomly selected negative specimens by rRT-PCR. The EV-D68 rRT-PCR showed diagnostic sensitivity and specificity of 98.6% and 97.5%, respectively. Our data suggest that the EV-D68 rRT-PCR is a reliable assay for detection of EV-D68 in clinical samples and has a potential to be used as a tool for rapid diagnosis and outbreak investigation of EV-D68-associated infections in clinical and public health laboratories. Copyright © 2015, American Society for Microbiology. All Rights Reserved.
Zhuge, Jian; Vail, Eric; Bush, Jeffrey L.; Singelakis, Lauren; Huang, Weihua; Nolan, Sheila M.; Haas, Janet P.; Engel, Helen; Della Posta, Millicent; Yoon, Esther C.; Fallon, John T.
2015-01-01
An outbreak of severe respiratory illness associated with enterovirus D68 (EV-D68) infection was reported in mid-August 2014 in the United States. In this study, we evaluated the diagnostic utility of an EV-D68-specific real-time reverse transcription-PCR (rRT-PCR) that was recently developed by the Centers for Disease Control and Prevention in clinical samples. Nasopharyngeal (NP) swab specimens from patients in a recent outbreak of respiratory illness in the lower Hudson Valley, New York State, were collected and examined for the presence of human rhinovirus or enterovirus using the FilmArray Respiratory Panel (RP) assay. Samples positive by RP were assessed using EV-D68 rRT-PCR, and the data were compared to results from sequencing analysis of partial VP1 and 5′ untranslated region (5′-UTR) sequences of the EV genome. A total of 285 RP-positive NP specimens (260 from the 2014 outbreak and 25 from 2013) were analyzed by rRT-PCR; EV-D68 was detected in 74 of 285 (26.0%) specimens examined. Data for comparisons between rRT-PCR and sequencing analysis were obtained from 194 NP specimens. EV-D68 detection was confirmed by sequencing analysis in 71 of 74 positive and in 1 of 120 randomly selected negative specimens by rRT-PCR. The EV-D68 rRT-PCR showed diagnostic sensitivity and specificity of 98.6% and 97.5%, respectively. Our data suggest that the EV-D68 rRT-PCR is a reliable assay for detection of EV-D68 in clinical samples and has a potential to be used as a tool for rapid diagnosis and outbreak investigation of EV-D68-associated infections in clinical and public health laboratories. PMID:25854481
Grolla, Allen; Jones, Steven M.; Fernando, Lisa; Strong, James E.; Ströher, Ute; Möller, Peggy; Paweska, Janusz T.; Burt, Felicity; Pablo Palma, Pedro; Sprecher, Armand; Formenty, Pierre; Roth, Cathy; Feldmann, Heinz
2011-01-01
Background Marburg virus (MARV), a zoonotic pathogen causing severe hemorrhagic fever in man, has emerged in Angola resulting in the largest outbreak of Marburg hemorrhagic fever (MHF) with the highest case fatality rate to date. Methodology/Principal Findings A mobile laboratory unit (MLU) was deployed as part of the World Health Organization outbreak response. Utilizing quantitative real-time PCR assays, this laboratory provided specific MARV diagnostics in Uige, the epicentre of the outbreak. The MLU operated over a period of 88 days and tested 620 specimens from 388 individuals. Specimens included mainly oral swabs and EDTA blood. Following establishing on site, the MLU operation allowed a diagnostic response in <4 hours from sample receiving. Most cases were found among females in the child-bearing age and in children less than five years of age. The outbreak had a high number of paediatric cases and breastfeeding may have been a factor in MARV transmission as indicated by the epidemiology and MARV positive breast milk specimens. Oral swabs were a useful alternative specimen source to whole blood/serum allowing testing of patients in circumstances of resistance to invasive procedures but limited diagnostic testing to molecular approaches. There was a high concordance in test results between the MLU and the reference laboratory in Luanda operated by the US Centers for Disease Control and Prevention. Conclusions/Significance The MLU was an important outbreak response asset providing support in patient management and epidemiological surveillance. Field laboratory capacity should be expanded and made an essential part of any future outbreak investigation. PMID:21629730
Ortuno-Gutierrez, Nimer; Zachariah, Rony; Woldeyohannes, Desalegn; Bangoura, Adama; Chérif, Gba-Foromo; Loua, Francis; Hermans, Veerle; Tayler-Smith, Katie; Sikhondze, Welile; Camara, Lansana-Mady
2016-01-01
Ten targeted health facilities supported by Damien Foundation (a Belgian Non Governmental Organization) and the National Tuberculosis (TB) Program in Conakry, Guinea. To uphold TB program performance during the Ebola outbreak in the presence of a package of pre-emptive additional measures geared at reinforcing the routine TB program, and ensuring Ebola infection control, health-workers safety and motivation. A retrospective comparative cohort study of a TB program assessing the performance before (2013) and during the (2014) Ebola outbreak. During the Ebola outbreak, all health facilities were maintained opened, there were no reported health-worker Ebola infections, drug stockouts or health staff absences. Of 2,475 presumptive pulmonary TB cases, 13% were diagnosed with TB in both periods (160/1203 in 2013 and 163/1272 in 2014). For new TB, treatment success improved from 84% before to 87% during the Ebola outbreak (P = 0.03). Adjusted Hazard-ratios (AHR) for an unfavorable outcome was alwo lower during the Ebola outbreak, AHR = 0.8, 95% CI:0.7-0.9, P = 0.04). Treatment success improved for HIV co-infected patients (72% to 80%, P<0.01). For retreatment patients, the proportion achieving treatment success was maintained (68% to 72%, P = 0.05). Uptake of HIV-testing and Cotrimoxazole Preventive Treatment was maintained over 85%, and Anti-Retroviral Therapy uptake increased from 77% in 2013 to 86% in 2014 (P<0.01). Contingency planning and health system and worker support during the 2014 Ebola outbreak was associated with encouraging and sustained TB program performance. This is of relevance to future outbreaks.
Frías-De-León, María Guadalupe; Ramírez-Bárcenas, José Antonio; Rodríguez-Arellanes, Gabriela; Velasco-Castrejón, Oscar; Taylor, Maria Lucia; Reyes-Montes, María Del Rocío
2017-03-01
Histoplasmosis is considered the most important systemic mycosis in Mexico, and its diagnosis requires fast and reliable methodologies. The present study evaluated the usefulness of PCR using Hcp100 and 1281-1283 (220) molecular markers in detecting Histoplasma capsulatum in occupational and recreational outbreaks. Seven clinical serum samples of infected individuals from three different histoplasmosis outbreaks were processed by enzyme-linked immunosorbent assay (ELISA) to titre anti-H. capsulatum antibodies and to extract DNA. Fourteen environmental samples were also processed for H. capsulatum isolation and DNA extraction. Both clinical and environmental DNA samples were analysed by PCR with Hcp100 and 1281-1283 (220) markers. Antibodies to H. capsulatum were detected by ELISA in all serum samples using specific antigens, and in six of these samples, the PCR products of both molecular markers were amplified. Four environmental samples amplified one of the two markers, but only one sample amplified both markers and an isolate of H. capsulatum was cultured from this sample. All PCR products were sequenced, and the sequences for each marker were analysed using the Basic Local Alignment Search Tool (BLASTn), which revealed 95-98 and 98-100 % similarities with the reference sequences deposited in the GenBank for Hcp100 and 1281-1283 (220) , respectively. Both molecular markers proved to be useful in studying histoplasmosis outbreaks because they are matched for pathogen detection in either clinical or environmental samples.
Yang, Eunjoo; Park, Hyun Woo; Choi, Yeon Hwa; Kim, Jusim; Munkhdalai, Lkhagvadorj; Musa, Ibrahim; Ryu, Keun Ho
2018-05-11
Early detection of infectious disease outbreaks is one of the important and significant issues in syndromic surveillance systems. It helps to provide a rapid epidemiological response and reduce morbidity and mortality. In order to upgrade the current system at the Korea Centers for Disease Control and Prevention (KCDC), a comparative study of state-of-the-art techniques is required. We compared four different temporal outbreak detection algorithms: the CUmulative SUM (CUSUM), the Early Aberration Reporting System (EARS), the autoregressive integrated moving average (ARIMA), and the Holt-Winters algorithm. The comparison was performed based on not only 42 different time series generated taking into account trends, seasonality, and randomly occurring outbreaks, but also real-world daily and weekly data related to diarrhea infection. The algorithms were evaluated using different metrics. These were namely, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), F1 score, symmetric mean absolute percent error (sMAPE), root-mean-square error (RMSE), and mean absolute deviation (MAD). Although the comparison results showed better performance for the EARS C3 method with respect to the other algorithms, despite the characteristics of the underlying time series data, Holt⁻Winters showed better performance when the baseline frequency and the dispersion parameter values were both less than 1.5 and 2, respectively.
Transmission and molecular characterisation of wild measles virus in Romania, 2008 to 2012.
Necula, G; Lazar, M; Stanescu, A; Pistol, A; Santibanez, S; Mankertz, A; Lupulescu, E
2013-12-12
Molecular characterisation of measles virus is a powerful tool for tracing transmission. Genotyping may prove the absence of endemic circulation of measles virus, i.e. transmission for more than 12 months, which is one of the criteria for verifying elimination of the disease. We have genetically characterised measles viruses detected in Romania from 2008 to 2012, focusing on the recent outbreaks from 2010 to 2012 that affected mainly groups with limited access to healthcare and schools. The findings emphasise the importance of genotyping during the different phases of an outbreak. A total of 8,170 cases were notified, and 5,093 (62%) of the 7,559 possible cases were serologically confirmed. RT-PCR was performed for 104 samples: from the 101 positive samples obtained from sporadic measles cases or clusters from different counties, 73 were genotyped. Sporadic measles cases associated with D4 and D5 viruses were observed from2008 to 2009. Genotype D4-Manchester was predominant in 2011 and 2012. In addition, the related variant D4-Maramures and MVs/Limoges.FRA/17.10[D4] and a few D4-Hamburg strains were detected. The detection of several distinct MV-D4 genotypes suggests multiple virus importations to Romania. The outbreak associated with D4 genotype is the second largest outbreak in Romania in less than 10 years.
Faires, Meredith C; Pearl, David L; Ciccotelli, William A; Berke, Olaf; Reid-Smith, Richard J; Weese, J Scott
2014-05-12
In hospitals, Clostridium difficile infection (CDI) surveillance relies on unvalidated guidelines or threshold criteria to identify outbreaks. This can result in false-positive and -negative cluster alarms. The application of statistical methods to identify and understand CDI clusters may be a useful alternative or complement to standard surveillance techniques. The objectives of this study were to investigate the utility of the temporal scan statistic for detecting CDI clusters and determine if there are significant differences in the rate of CDI cases by month, season, and year in a community hospital. Bacteriology reports of patients identified with a CDI from August 2006 to February 2011 were collected. For patients detected with CDI from March 2010 to February 2011, stool specimens were obtained. Clostridium difficile isolates were characterized by ribotyping and investigated for the presence of toxin genes by PCR. CDI clusters were investigated using a retrospective temporal scan test statistic. Statistically significant clusters were compared to known CDI outbreaks within the hospital. A negative binomial regression model was used to identify associations between year, season, month and the rate of CDI cases. Overall, 86 CDI cases were identified. Eighteen specimens were analyzed and nine ribotypes were classified with ribotype 027 (n = 6) the most prevalent. The temporal scan statistic identified significant CDI clusters at the hospital (n = 5), service (n = 6), and ward (n = 4) levels (P ≤ 0.05). Three clusters were concordant with the one C. difficile outbreak identified by hospital personnel. Two clusters were identified as potential outbreaks. The negative binomial model indicated years 2007-2010 (P ≤ 0.05) had decreased CDI rates compared to 2006 and spring had an increased CDI rate compared to the fall (P = 0.023). Application of the temporal scan statistic identified several clusters, including potential outbreaks not detected by hospital personnel. The identification of time periods with decreased or increased CDI rates may have been a result of specific hospital events. Understanding the clustering of CDIs can aid in the interpretation of surveillance data and lead to the development of better early detection systems.
European Surveillance for West Nile Virus in Mosquito Populations
Engler, Olivier; Savini, Giovanni; Papa, Anna; Figuerola, Jordi; Groschup, Martin H.; Kampen, Helge; Medlock, Jolyon; Vaux, Alexander; Wilson, Anthony J.; Werner, Doreen; Jöst, Hanna; Goffredo, Maria; Capelli, Gioia; Federici, Valentina; Tonolla, Mauro; Patocchi, Nicola; Flacio, Eleonora; Portmann, Jasmine; Rossi-Pedruzzi, Anya; Mourelatos, Spiros; Ruiz, Santiago; Vázquez, Ana; Calzolari, Mattia; Bonilauri, Paolo; Dottori, Michele; Schaffner, Francis; Mathis, Alexander; Johnson, Nicholas
2013-01-01
A wide range of arthropod-borne viruses threaten both human and animal health either through their presence in Europe or through risk of introduction. Prominent among these is West Nile virus (WNV), primarily an avian virus, which has caused multiple outbreaks associated with human and equine mortality. Endemic outbreaks of West Nile fever have been reported in Italy, Greece, France, Romania, Hungary, Russia and Spain, with further spread expected. Most outbreaks in Western Europe have been due to infection with WNV Lineage 1. In Eastern Europe WNV Lineage 2 has been responsible for human and bird mortality, particularly in Greece, which has experienced extensive outbreaks over three consecutive years. Italy has experienced co-circulation with both virus lineages. The ability to manage this threat in a cost-effective way is dependent on early detection. Targeted surveillance for pathogens within mosquito populations offers the ability to detect viruses prior to their emergence in livestock, equine species or human populations. In addition, it can establish a baseline of mosquito-borne virus activity and allow monitoring of change to this over time. Early detection offers the opportunity to raise disease awareness, initiate vector control and preventative vaccination, now available for horses, and encourage personal protection against mosquito bites. This would have major benefits through financial savings and reduction in equid morbidity/mortality. However, effective surveillance that predicts virus outbreaks is challenged by a range of factors including limited resources, variation in mosquito capture rates (too few or too many), difficulties in mosquito identification, often reliant on specialist entomologists, and the sensitive, rapid detection of viruses in mosquito pools. Surveillance for WNV and other arboviruses within mosquito populations varies between European countries in the extent and focus of the surveillance. This study reviews the current status of WNV in mosquito populations across Europe and how this is informing our understanding of virus epidemiology. Key findings such as detection of virus, presence of vector species and invasive mosquito species are summarized, and some of the difficulties encountered when applying a cost-effective surveillance programme are highlighted. PMID:24157510
DOE Office of Scientific and Technical Information (OSTI.GOV)
Goodsman, Devin W.; Grosklos, Guenchik; Aukema, Brian H.
Warmer climates are predicted to increase bark beetle outbreak frequency, severity, and range. Even in favorable climates, however, outbreaks can decelerate due to resource limitation, which necessitates the inclusion of competition for limited resources in analyses of climatic effects on populations. We evaluated several hypotheses of how climate impacts mountain pine beetle reproduction using an extensive 9-year dataset, in which nearly 10,000 trees were sampled across a region of approximately 90,000 km 2, that was recently invaded by the mountain pine beetle in Alberta, Canada. Our analysis supports the hypothesis of a positive effect of warmer winter temperatures on mountainmore » pine beetle overwinter survival and provides evidence that the increasing trend in minimum winter temperatures over time in North America is an important driver of increased mountain pine beetle reproduction across the region. Although we demonstrate a consistent effect of warmer minimum winter temperatures on mountain pine beetle reproductive rates that is evident at the landscape and regional scales, this effect is overwhelmed by the effect of competition for resources within trees at the site level. Our results suggest that detection of the effects of a warming climate on bark beetle populations at small spatial scales may be difficult without accounting for negative density dependence due to competition for resources.« less
Withrow, J R; Smith, E L; Koch, F H; Yemshanov, D
2015-03-01
In pest risk assessment it is frequently necessary to make time-critical decisions regarding management of expanding pest populations. When an invasive pest outbreak is expanding rapidly, preemptive quarantine of areas that are under imminent threat of infestation is one of only a few available management tools that can be implemented quickly to help control the expansion. The preemptive quarantine of locations that surround an infested area also acts as a safeguard to counteract the risk of failed detections of the pest in field surveys. In this paper, we present a method that assesses the suitability of preemptive quarantine measures at the level of small geographical subdivisions (U.S. counties). The cost of a preemptive quarantine in a given county is weighed against the protective benefit of delaying the spread of an outbreak to other neighboring counties. We demonstrate the approach with a decision support model that estimates the suitability of preemptive quarantine across multiple counties that surround areas infested with the emerald ash borer (Agrilus planipennis Fairmaire (EAB), Coleoptera: Buprestidae), an emerging major threat to ash tree species (Fraxinus spp.) in North America. The model identifies the U.S. counties where the installation of preemptive quarantine would most effectively slow the spread of EAB populations and reduce risk to high-value areas. Copyright © 2014 Elsevier Ltd. All rights reserved.
Goodsman, Devin W; Grosklos, Guenchik; Aukema, Brian H; Whitehouse, Caroline; Bleiker, Katherine P; McDowell, Nate G; Middleton, Richard S; Xu, Chonggang
2018-05-29
Warmer climates are predicted to increase bark beetle outbreak frequency, severity, and range. Even in favorable climates, however, outbreaks can decelerate due to resource limitation, which necessitates the inclusion of competition for limited resources in analyses of climatic effects on populations. We evaluated several hypotheses of how climate impacts mountain pine beetle reproduction using an extensive 9-year dataset, in which nearly 10,000 trees were sampled across a region of approximately 90,000 km 2 , that was recently invaded by the mountain pine beetle in Alberta, Canada. Our analysis supports the hypothesis of a positive effect of warmer winter temperatures on mountain pine beetle overwinter survival and provides evidence that the increasing trend in minimum winter temperatures over time in North America is an important driver of increased mountain pine beetle reproduction across the region. Although we demonstrate a consistent effect of warmer minimum winter temperatures on mountain pine beetle reproductive rates that is evident at the landscape and regional scales, this effect is overwhelmed by the effect of competition for resources within trees at the site level. Our results suggest that detection of the effects of a warming climate on bark beetle populations at small spatial scales may be difficult without accounting for negative density dependence due to competition for resources. © 2018 The Authors. Global Change Biology Published by John Wiley & Sons Ltd.
Goodsman, Devin W.; Grosklos, Guenchik; Aukema, Brian H.; ...
2018-05-29
Warmer climates are predicted to increase bark beetle outbreak frequency, severity, and range. Even in favorable climates, however, outbreaks can decelerate due to resource limitation, which necessitates the inclusion of competition for limited resources in analyses of climatic effects on populations. We evaluated several hypotheses of how climate impacts mountain pine beetle reproduction using an extensive 9-year dataset, in which nearly 10,000 trees were sampled across a region of approximately 90,000 km 2, that was recently invaded by the mountain pine beetle in Alberta, Canada. Our analysis supports the hypothesis of a positive effect of warmer winter temperatures on mountainmore » pine beetle overwinter survival and provides evidence that the increasing trend in minimum winter temperatures over time in North America is an important driver of increased mountain pine beetle reproduction across the region. Although we demonstrate a consistent effect of warmer minimum winter temperatures on mountain pine beetle reproductive rates that is evident at the landscape and regional scales, this effect is overwhelmed by the effect of competition for resources within trees at the site level. Our results suggest that detection of the effects of a warming climate on bark beetle populations at small spatial scales may be difficult without accounting for negative density dependence due to competition for resources.« less
Tactics and strategies for managing Ebola outbreaks and the salience of immunization.
Getz, Wayne M; Gonzalez, Jean-Paul; Salter, Richard; Bangura, James; Carlson, Colin; Coomber, Moinya; Dougherty, Eric; Kargbo, David; Wolfe, Nathan D; Wauquier, Nadia
2015-01-01
We present a stochastic transmission chain simulation model for Ebola viral disease (EVD) in West Africa, with the salutary result that the virus may be more controllable than previously suspected. The ongoing tactics to detect cases as rapidly as possible and isolate individuals as safely as practicable is essential to saving lives in the current outbreaks in Guinea, Liberia, and Sierra Leone. Equally important are educational campaigns that reduce contact rates between susceptible and infectious individuals in the community once an outbreak occurs. However, due to the relatively low R 0 of Ebola (around 1.5 to 2.5 next generation cases are produced per current generation case in naïve populations), rapid isolation of infectious individuals proves to be highly efficacious in containing outbreaks in new areas, while vaccination programs, even with low efficacy vaccines, can be decisive in curbing future outbreaks in areas where the Ebola virus is maintained in reservoir populations.
Ford, Laura; Wang, Qinning; Stafford, Russell; Ressler, Kelly-Anne; Norton, Sophie; Shadbolt, Craig; Hope, Kirsty; Franklin, Neil; Krsteski, Radomir; Carswell, Adrienne; Carter, Glen P; Seemann, Torsten; Howard, Peter; Valcanis, Mary; Castillo, Cristina Fabiola Sotomayor; Bates, John; Glass, Kathryn; Williamson, Deborah A; Sintchenko, Vitali; Howden, Benjamin P; Kirk, Martyn D
2018-05-01
Salmonella Typhimurium is a common cause of foodborne illness in Australia. We report on seven outbreaks of Salmonella Typhimurium multilocus variable-number tandem-repeat analysis (MLVA) 03-26-13-08-523 (European convention 2-24-12-7-0212) in three Australian states and territories investigated between November 2015 and March 2016. We identified a common egg grading facility in five of the outbreaks. While no Salmonella Typhimurium was detected at the grading facility and eggs could not be traced back to a particular farm, whole genome sequencing (WGS) of isolates from cases from all seven outbreaks indicated a common source. WGS was able to provide higher discriminatory power than MLVA and will likely link more Salmonella Typhimurium cases between states and territories in the future. National harmonization of Salmonella surveillance is important for effective implementation of WGS for Salmonella outbreak investigations.
Epidemiology and Management of the 2013-16 West African Ebola Outbreak.
Boisen, M L; Hartnett, J N; Goba, A; Vandi, M A; Grant, D S; Schieffelin, J S; Garry, R F; Branco, L M
2016-09-29
The 2013-16 West African Ebola outbreak is the largest, most geographically dispersed, and deadliest on record, with 28,616 suspected cases and 11,310 deaths recorded to date in Guinea, Liberia, and Sierra Leone. We provide a review of the epidemiology and management of the 2013-16 Ebola outbreak in West Africa aimed at stimulating reflection on lessons learned that may improve the response to the next international health crisis caused by a pathogen that emerges in a region of the world with a severely limited health care infrastructure. Surveillance efforts employing rapid and effective point-of-care diagnostics designed for environments that lack advanced laboratory infrastructure will greatly aid in early detection and containment efforts during future outbreaks. Introduction of effective therapeutics and vaccines against Ebola into the public health system and the biodefense armamentarium is of the highest priority if future outbreaks are to be adequately managed and contained in a timely manner.
Anthrax Outbreaks in Bangladesh, 2009–2010
Chakraborty, Apurba; Khan, Salah Uddin; Hasnat, Mohammed Abul; Parveen, Shahana; Islam, M. Saiful; Mikolon, Andrea; Chakraborty, Ranjit Kumar; Ahmed, Be-Nazir; Ara, Khorsed; Haider, Najmul; Zaki, Sherif R.; Hoffmaster, Alex R.; Rahman, Mahmudur; Luby, Stephen P.; Hossain, M. Jahangir
2012-01-01
During August 2009–October 2010, a multidisciplinary team investigated 14 outbreaks of animal and human anthrax in Bangladesh to identify the etiology, pathway of transmission, and social, behavioral, and cultural factors that led to these outbreaks. The team identified 140 animal cases of anthrax and 273 human cases of cutaneous anthrax. Ninety one percent of persons in whom cutaneous anthrax developed had history of butchering sick animals, handling raw meat, contact with animal skin, or were present at slaughtering sites. Each year, Bacillus anthracis of identical genotypes were isolated from animal and human cases. Inadequate livestock vaccination coverage, lack of awareness of the risk of anthrax transmission from animal to humans, social norms and poverty contributed to these outbreaks. Addressing these challenges and adopting a joint animal and human health approach could contribute to detecting and preventing such outbreaks in the future. PMID:22492157
DETECTION OF CRYPTOSPORIDIUM OOCYSTS IN WATER MATRICES
Since the advent and recognition of waterborne outbreaks of cryptosporidiosis great effort has been expended on development of methods for detecting Cryptosporidium oocysts in water. Oocysts recovery rates using a method originally developed for detecting Giardia cysts ranged fr...
Role of poultry in the H7N9 influenza outbreaks in China
USDA-ARS?s Scientific Manuscript database
The outbreaks of avian influenza A (H7N9) occurring in China in 2013 and 2014 have resulted in more than 370 human cases with a 30% fatality rate. Most of these infections are believed to result from exposure to infected poultry or contaminated environments as the viruses have been detected in avia...
West Nile Virus Outbreak in Houston and Harris County, Texas, USA, 2014.
Martinez, Diana; Murray, Kristy O; Reyna, Martin; Arafat, Raouf R; Gorena, Roberto; Shah, Umair A; Debboun, Mustapha
2017-08-01
Since 2002, West Nile virus (WNV) has been detected every year in Houston and the surrounding Harris County, Texas. In 2014, the largest WNV outbreak to date occurred, comprising 139 cases and causing 2 deaths. Additionally, 1,286 WNV-positive mosquito pools were confirmed, the most reported in a single mosquito season.
An outbreak of hepatitis A in Roma populations living in three prefectures in Greece.
Vantarakis, A; Nearxou, A; Pagonidis, D; Melegos, F; Seretidis, J; Kokkinos, P; Zarkadis, I; Parasidis, T; Alamanos, Y
2010-07-01
An outbreak of hepatitis A virus (HAV) infection affected Roma populations living in three prefectures of northeastern Greece. Between July and November 2007, 124 cases were reported. We carried out investigations to characterize the pathogen, to identify the source of infection and the route of transmission. Using the RT-PCR technique, HAV strains of the same genotype were detected in all sera from a subset of patients with acute disease. These showed more than 99.8% identity, suggesting a common source. A questionnaire was also completed to collect clinical and epidemiological information. The outbreak affected mainly Roma children aged <10 years. An inspection of Roma settlements showed that poor sanitary conditions were associated with the HAV outbreak.
Brault, Aaron C.; Fang, Ying; Reisen, William K.
2015-01-01
Following the introduction of West Nile virus into California during the summer of 2003, public health and vector control programs expanded surveillance efforts and were in need of diagnostics capable of rapid, sensitive, and specific detection of arbovirus infections of mosquitoes to inform decision support for intervention. Development of a multiplex TaqMan or real-time semiquantitative reverse transcription polymerase chain reaction (RT-PCR) assay in which three virus specific primer–probe sets were used in the same reaction is described herein for the detection of western equine encephalomyelitis, St. Louis encephalitis and West Nile viral RNA. Laboratory validation and field data from 10 transmission seasons are reported. The comparative sensitivity and specificity of this multiplex assay to singleplex RT-PCR as well as an antigen detection (rapid analyte measurement platform) and standard plaque assays indicate this assay to be rapid and useful in providing mosquito infection data to estimate outbreak risk. PMID:26334826
Bopp, Dianna J.; Sauders, Brian D.; Waring, Alfred L.; Ackelsberg, Joel; Dumas, Nellie; Braun-Howland, Ellen; Dziewulski, David; Wallace, Barbara J.; Kelly, Molly; Halse, Tanya; Musser, Kimberlee Aruda; Smith, Perry F.; Morse, Dale L.; Limberger, Ronald J.
2003-01-01
The largest reported outbreak of waterborne Escherichia coli O157:H7 in the United States occurred in upstate New York following a county fair in August 1999. Culture methods were used to isolate E. coli O157:H7 from specimens from 128 of 775 patients with suspected infections. Campylobacter jejuni was also isolated from stools of 44 persons who developed diarrheal illness after attending this fair. There was one case of a confirmed coinfection with E. coli O157:H7 and C. jejuni. Molecular detection of stx1 and stx2 Shiga toxin genes, immunomagnetic separation (IMS), and selective culture enrichment were utilized to detect and isolate E. coli O157:H7 from an unchlorinated well and its distribution points, a dry well, and a nearby septic tank. PCR for stx1 and stx2 was shown to provide a useful screen for toxin-producing E. coli O157:H7, and IMS subculture improved recovery. Pulsed-field gel electrophoresis (PFGE) was used to compare patient and environmental E. coli O157:H7 isolates. Among patient isolates, 117 of 128 (91.5%) were type 1 or 1a (three or fewer bands different). Among the water distribution system isolates, 13 of 19 (68%) were type 1 or 1a. Additionally, PFGE of C. jejuni isolates revealed that 29 of 35 (83%) had indistinguishable PFGE patterns. The PFGE results implicated the water distribution system as the main source of the E. coli O157:H7 outbreak. This investigation demonstrates the potential for outbreaks involving more than one pathogen and the importance of analyzing isolates from multiple patients and environmental samples to develop a better understanding of bacterial transmission during an outbreak. PMID:12517844
Social Network Sensors for Early Detection of Contagious Outbreaks
Christakis, Nicholas A.; Fowler, James H.
2010-01-01
Current methods for the detection of contagious outbreaks give contemporaneous information about the course of an epidemic at best. It is known that individuals near the center of a social network are likely to be infected sooner during the course of an outbreak, on average, than those at the periphery. Unfortunately, mapping a whole network to identify central individuals who might be monitored for infection is typically very difficult. We propose an alternative strategy that does not require ascertainment of global network structure, namely, simply monitoring the friends of randomly selected individuals. Such individuals are known to be more central. To evaluate whether such a friend group could indeed provide early detection, we studied a flu outbreak at Harvard College in late 2009. We followed 744 students who were either members of a group of randomly chosen individuals or a group of their friends. Based on clinical diagnoses, the progression of the epidemic in the friend group occurred 13.9 days (95% C.I. 9.9–16.6) in advance of the randomly chosen group (i.e., the population as a whole). The friend group also showed a significant lead time (p<0.05) on day 16 of the epidemic, a full 46 days before the peak in daily incidence in the population as a whole. This sensor method could provide significant additional time to react to epidemics in small or large populations under surveillance. The amount of lead time will depend on features of the outbreak and the network at hand. The method could in principle be generalized to other biological, psychological, informational, or behavioral contagions that spread in networks. PMID:20856792
Lee, Jung-Seok; Carabali, Mabel; Lim, Jacqueline K; Herrera, Victor M; Park, Il-Yeon; Villar, Luis; Farlow, Andrew
2017-07-10
Dengue has been prevalent in Colombia with high risk of outbreaks in various locations. While the prediction of dengue epidemics will bring significant benefits to the society, accurate forecasts have been a challenge. Given competing health demands in Colombia, it is critical to consider the effective use of the limited healthcare resources by identifying high risk areas for dengue fever. The Climate Risk Factor (CRF) index was constructed based upon temperature, precipitation, and humidity. Considering the conditions necessary for vector survival and transmission behavior, elevation and population density were taken into account. An Early Warning Signal (EWS) model was developed by estimating the elasticity of the climate risk factor function to detect dengue epidemics. The climate risk factor index was further estimated at the smaller geographical unit (5 km by 5 km resolution) to identify populations at high risk. From January 2007 to December 2015, the Early Warning Signal model successfully detected 75% of the total number of outbreaks 1 ~ 5 months ahead of time, 12.5% in the same month, and missed 12.5% of all outbreaks. The climate risk factors showed that populations at high risk are concentrated in the Western part of Colombia where more suitable climate conditions for vector mosquitoes and the high population level were observed compared to the East. This study concludes that it is possible to detect dengue outbreaks ahead of time and identify populations at high risk for various disease prevention activities based upon observed climate and non-climate information. The study outcomes can be used to minimize potential societal losses by prioritizing limited healthcare services and resources, as well as by conducting vector control activities prior to experiencing epidemics.
Christner, Martin; Trusch, Maria; Rohde, Holger; Kwiatkowski, Marcel; Schlüter, Hartmut; Wolters, Manuel; Aepfelbacher, Martin; Hentschke, Moritz
2014-01-01
Background In 2011 northern Germany experienced a large outbreak of Shiga-Toxigenic Escherichia coli O104:H4. The large amount of samples sent to microbiology laboratories for epidemiological assessment highlighted the importance of fast and inexpensive typing procedures. We have therefore evaluated the applicability of a MALDI-TOF mass spectrometry based strategy for outbreak strain identification. Methods Specific peaks in the outbreak strain’s spectrum were identified by comparative analysis of archived pre-outbreak spectra that had been acquired for routine species-level identification. Proteins underlying these discriminatory peaks were identified by liquid chromatography tandem mass spectrometry and validated against publicly available databases. The resulting typing scheme was evaluated against PCR genotyping with 294 E. coli isolates from clinical samples collected during the outbreak. Results Comparative spectrum analysis revealed two characteristic peaks at m/z 6711 and m/z 10883. The underlying proteins were found to be of low prevalence among genome sequenced E. coli strains. Marker peak detection correctly classified 292 of 293 study isolates, including all 104 outbreak isolates. Conclusions MALDI-TOF mass spectrometry allowed for reliable outbreak strain identification during a large outbreak of Shiga-Toxigenic E. coli. The applied typing strategy could probably be adapted to other typing tasks and might facilitate epidemiological surveys as part of the routine pathogen identification workflow. PMID:25003758
Cope, J.R.; Prosser, A.; Nowicki, S.; Roberts, M.W.; Scheer, D.; Anderson, C.; Longsworth, A.; Parsons, C.; Goldschmidt, D.; Johnston, S.; Bishop, H.; Xiao, L.; Hill, V.; Beach, M.; Hlavsa, M.C.
2015-01-01
Summary The incidence of recreational water–associated outbreaks in the United States has significantly increased, driven, at least in part, by outbreaks both caused by Cryptosporidium and associated with treated recreational water venues. Because of the parasite's extreme chlorine tolerance, transmission can occur even in well-maintained treated recreational water venues, (e.g., pools) and a focal cryptosporidiosis outbreak can evolve into a community-wide outbreak associated with multiple recreational water venues and settings (e.g., child care facilities). In August 2004 in Auglaize County, Ohio, multiple cryptosporidiosis cases were identified and anecdotally linked to Pool A. Within 5 days of the first case being reported, Pool A was hyperchlorinated to achieve 99.9% Cryptosporidium inactivition. A case-control study was launched to epidemiologically ascertain the outbreak source 11 days later. A total of 150 confirmed and probable cases were identified; the temporal distribution of illness onset was peaked, indicating a point-source exposure. Cryptosporidiosis was significantly associated with swimming in Pool A (matched odds ratio 121.7, 95% confidence interval 27.4–∞) but not with another venue or setting. The findings of this investigation suggest that proactive implementation of control measures, when increased Cryptosporidium transmission is detected but before an outbreak source is epidemiologically ascertained, might prevent a focal cryptosporidiosis outbreak from evolving into a community-wide outbreak. PMID:25907106
Tularaemia outbreaks in Sakarya, Turkey: case-control and environmental studies.
Meric, M; Sayan, M; Dundar, D; Willke, A
2010-08-01
Tularaemia is an important zoonotic disease that leads to outbreaks. This study aimed to compare the epidemiological characteristics of two tularaemia outbreaks that occurred in the Sakarya region of Turkey, analyse the risk factors for the development of outbreaks and identify Francisella (F.) tularensis in the water samples. Two tularaemia outbreaks occurred in the Kocadongel village in 2005 and 2006. A field investigation and a case-control study with 47 cases and 47 healthy households were performed during the second outbreak. Clinical samples from the patients and filtrated water samples were analysed for F. tularensis via real-time polymerase chain reaction. From the two outbreaks, a total of 58 patients were diagnosed with oropharyngeal tularaemia based on their clinical and serological results. Both outbreaks occurred between the months of January and April, and the number of patients peaked in February. Logistic regression analysis revealed that the consumption of natural spring water was the only significant risk factor for tularaemia infection (odds ratio 3.5, confidence interval 1.23-10.07). F. tularensis was detected in eight clinical samples and in the filtrated natural spring water. This study is the first report of tularaemia from this region. The results show that both tularaemia outbreaks were related to the consumption of untreated natural spring water. To prevent waterborne tularaemia, community water supplies should be treated and checked periodically.
Silwedel, C; Vogel, U; Claus, H; Glaser, K; Speer, C P; Wirbelauer, J
2016-06-01
Outbreaks of infections with multidrug-resistant bacteria in neonatal intensive care units (NICUs) pose a major threat, especially to extremely preterm infants. This study describes a 35-day outbreak of multidrug-resistant Escherichia coli (E. coli) in a tertiary-level NICU in Germany. To underline the importance of surveillance policies in the particularly vulnerable cohort of preterm infants and to describe the efficacy of outbreak control strategies. Data were collected retrospectively from medical reports. Infants and environment were tested for E. coli. The outbreak affected a total of 13 infants between 25(+1) and 35(+0) weeks of gestation with seven infants showing signs of infection. The outbreak strain was identified as E. coli sequence type 131. Environmental screening provided no evidence for an environmental source. Through colonization surveillance and immediate and adequate treatment of potentially infected preterm infants, no fatalities occurred. Outbreak control was achieved by strict contact precautions, enhanced screening and temporary relocation of the NICU. Relocation and reconstruction improved the NICU's structural layout, focusing on isolation capacities. Follow-up indicated carriage for several months in some infants. Routine surveillance allowed early detection of the outbreak. The identification of carriers of the outbreak strain was successfully used to direct antibiotic treatment in case of infection. Enhanced hygienic measures and ward relocation were instrumental in controlling the outbreak. Copyright © 2016. Published by Elsevier Ltd.
[Norovirus outbreaks in hospitals and nursing homes in Catalonia, Spain].
Godoy, Pere; Domínguez, Angela; Alvarez, Josep; Camps, Neus; Barrabeig, Irene; Bartolomé, Rosa; Sala, María Rosa; Ferre, Dolors; Pañella, Helena; Torres, Joan; Minguell, Sofía; Alsedà, Miquel; Pumares, Analía
2009-01-01
The low infectious dose and multiple transmission routes favour the appearance of norovirus outbreaks. The objective of this study was to compare the incidence of norovirus outbreaks in hospitals and nursing homes in Catalonia. A descriptive study of norovirus outbreaks between 15/10/2004 and 30/10/2005 was carried out. An epidemiological survey was completed for each outbreak. Norovirus in clinical samples was determined by PCR techniques. The incidence in each centre and the annual incidence of outbreaks by centre were calculated. Differences were calculated using the chi-square test and the Student's t test, taking a p value of > 0.05 as significant. Seventeen outbreaks (6 in hospitals and 11 in nursing homes) were detected. The global attack rate was 33.4% (652/1951) and was slightly higher in nursing homes (35.2%) than in hospitals (31.4%). A total of 94.1% (16/17) of outbreaks were caused by person-to-person transmission and only 5.9% (1/17) by foods. The mean number of days between the first and last case was 11.4 (SD = 6.9). The mean duration of symptoms was 2.39 days (SD=1.6), and was higher hospitals, 2.63 (SD=1.7), than in nursing homes, 1.97 (SD=1.7) (p < 0.0001). Norovirus is responsible for a large number of outbreaks due to person-to-person transmission. Control should be standardized to reduce the number and duration of outbreaks.
Arroyo, Montserrat; Perez, Andres M; Rodriguez, Luis L
2011-02-01
To characterize the temporal and spatial distribution and reproductive ratio of vesicular stomatitis (VS) outbreaks reported in Mexico in 2008. Bovine herds in Mexico in which VS outbreaks were officially reported and confirmed from January 1 through December 31, 2008. The Poisson model of the space-time scan statistic was used to identify periods and geographical locations at highest risk for VS in Mexico in 2008. The herd reproductive ratio (R(h)) of the epidemic was computed by use of the doubling-time method. 1 significant space-time cluster of VS was detected in the state of Michoacan from September 4 through December 10, 2008. The temporal extent of the VS outbreaks and the value and pattern of decrease of the R(h) were different in the endemic zone of Tabasco and Chiapas, compared with findings in the region included in the space-time cluster. The large number of VS outbreaks reported in Mexico in 2008 was associated with the spread of the disease from the endemic zone in southern Mexico to areas sporadically affected by the disease. Results suggested that implementation of a surveillance system in the endemic zone of Mexico aimed at early detection of changes in the value of R(h) and space-time clustering of the disease could help predict occurrence of future VS outbreaks originating from this endemic zone. This information will help prevent VS spread into regions of Mexico and neighboring countries that are only sporadically affected by the disease.
Real-Time Surveillance in Emergencies Using the Early Warning Alert and Response Network.
Cordes, Kristina M; Cookson, Susan T; Boyd, Andrew T; Hardy, Colleen; Malik, Mamunur Rahman; Mala, Peter; El Tahir, Khalid; Everard, Marthe; Jasiem, Mohamad; Husain, Farah
2017-11-01
Humanitarian emergencies often result in population displacement and increase the risk for transmission of communicable diseases. To address the increased risk for outbreaks during humanitarian emergencies, the World Health Organization developed the Early Warning Alert and Response Network (EWARN) for early detection of epidemic-prone diseases. The US Centers for Disease Control and Prevention has worked with the World Health Organization, ministries of health, and other partners to support EWARN through the implementation and evaluation of these systems and the development of standardized guidance. Although protocols have been developed for the implementation and evaluation of EWARN, a need persists for standardized training and additional guidance on supporting these systems remotely when access to affected areas is restricted. Continued collaboration between partners and the Centers for Disease Control and Prevention for surveillance during emergencies is necessary to strengthen capacity and support global health security.
Real-Time Surveillance in Emergencies Using the Early Warning Alert and Response Network
Cordes, Kristina M.; Cookson, Susan T.; Boyd, Andrew T.; Hardy, Colleen; Malik, Mamunur Rahman; Mala, Peter; El Tahir, Khalid; Everard, Marthe; Jasiem, Mohamad
2017-01-01
Humanitarian emergencies often result in population displacement and increase the risk for transmission of communicable diseases. To address the increased risk for outbreaks during humanitarian emergencies, the World Health Organization developed the Early Warning Alert and Response Network (EWARN) for early detection of epidemic-prone diseases. The US Centers for Disease Control and Prevention has worked with the World Health Organization, ministries of health, and other partners to support EWARN through the implementation and evaluation of these systems and the development of standardized guidance. Although protocols have been developed for the implementation and evaluation of EWARN, a need persists for standardized training and additional guidance on supporting these systems remotely when access to affected areas is restricted. Continued collaboration between partners and the Centers for Disease Control and Prevention for surveillance during emergencies is necessary to strengthen capacity and support global health security. PMID:29155660
Emergence of norovirus GI.2 outbreaks in military camps in Singapore.
Ho, Zheng Jie Marc; Vithia, Gunalan; Ng, Ching Ging; Maurer-Stroh, Sebastian; Tan, Clive M; Loh, Jimmy; Lin, Tzer Pin Raymond; Lee, Jian Ming Vernon
2015-02-01
Simultaneous acute gastroenteritis (AGE) outbreaks occurred at two military camps. This study details the epidemiological findings, explores possible origins, and discusses preventive measures. Investigations included attack rate surveys, symptom surveys, hygiene inspections, and the testing of water, food, and stool samples. DNA/RNA was extracted from stool samples and amplified via real-time reverse transcription PCR (RT-PCR). Partial and full-length capsid nucleotide sequences were obtained, phylogenetic relationships inferred, and homology modelling of antigenic sites performed. The military outbreaks involved 775 persons and were preceded by two AGE outbreaks at restaurants in the local community. The outbreak was longer and larger in the bigger camp (21 days, attack rate 15.0%) than the smaller camp (6 days, attack rate 8.3%). Of 198 stool samples, norovirus GI.2 was detected in 32.5% (larger camp) and 28.6% (smaller camp). These were essentially identical to preceding community outbreaks. Antigenic site homology modelling also showed differences between identified and more common AGE outbreak strains (norovirus GII.4). Differences observed highlight difficulties in controlling person-to-person outbreaks among large groups in close proximity (e.g., military trainees). Distinct differences in antigenic sites may have contributed to increased immunological susceptibility of the soldiers to infection. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.
Chen, Y I; Burall, Laurel S; Macarisin, Dumitru; Pouillot, Régis; Strain, Errol; DE Jesus, Antonio J; Laasri, Anna; Wang, Hua; Ali, Laila; Tatavarthy, Aparna; Zhang, Guodong; Hu, Lijun; Day, James; Kang, Jihun; Sahu, Surasri; Srinivasan, Devayani; Klontz, Karl; Parish, Mickey; Evans, Peter S; Brown, Eric W; Hammack, Thomas S; Zink, Donald L; Datta, Atin R
2016-11-01
A most-probable-number (MPN) method was used to enumerate Listeria monocytogenes in 2,320 commercial ice cream scoops manufactured on a production line that was implicated in a 2015 listeriosis outbreak in the United States. The analyzed samples were collected from seven lots produced in November 2014, December 2014, January 2015, and March 2015. L. monocytogenes was detected in 99% (2,307 of 2,320) of the tested samples (lower limit of detection, 0.03 MPN/g), 92% of which were contaminated at <20 MPN/g. The levels of L. monocytogenes in these samples had a geometric mean per lot of 0.15 to 7.1 MPN/g. The prevalence and enumeration data from an unprecedented large number of naturally contaminated ice cream products linked to a listeriosis outbreak provided a unique data set for further understanding the risk associated with L. monocytogenes contamination for highly susceptible populations.
The scenario of norovirus contamination in food and food handlers.
Tuan Zainazor, C; Hidayah, M S Noor; Chai, L C; Tunung, R; Ghazali, F Mohamad; Son, R
2010-02-01
Recently, many cases related to viral gastroenteritis outbreaks have been reported all over the world. Noroviruses are found to be leading as the major cause of outbreaks of acute gastroenteritis. Patients with the acute gastroenteritis normally found to be positive with norovirus when stools and vomit were analyzed. This paper reviews various activities and previous reports that describe norovirus contaminated in various food matrixes and relationship between food handlers. Lately, a numbers of norovirus outbreaks have been reported which are involved fresh produce (such as vegetables, fruits), shellfish and prepared food. Food produces by infected food handlers may therefore easily contaminated. In addition, food that required much handling and have been eaten without heat treatment gave the high risk for getting foodborne illnesses. The standard method for detection of norovirus has already been available for stool samples. However, only few methods for detection of norovirus in food samples have been developed until now.
Kost, Gerald J; Ferguson, William; Truong, Anh-Thu; Hoe, Jackie; Prom, Daisy; Banpavichit, Arirat; Kongpila, Surin
2015-01-01
Ultrahigh sensitivity and specificity assays that detect Ebola virus disease or other highly contagious and deadly diseases quickly and successfully upstream in Spatial Care Paths™ can stop outbreaks from escalating into devastating epidemics ravaging communities locally and countries globally. Even had the WHO and CDC responded more quickly and not misjudged the dissemination of Ebola in West Africa and other world regions, mobile rapid diagnostics were, and still are, not readily available for immediate and definitive diagnosis, a stunning strategic flaw that needs correcting worldwide. This article strategizes point-of-care testing for diagnosis, triage, monitoring, recovery and stopping outbreaks in the USA and other countries; reviews Ebola molecular diagnostics, summarizes USA FDA emergency use authorizations and documents why they should not be stop-gaps; and reduces community risk from internal and external infectious disease threats by enabling public health at points of need.
Hayashi, Y; Ando, T; Utagawa, E; Sekine, S; Okada, S; Yabuuchi, K; Miki, T; Ohashi, M
1989-08-01
Small, round-structured virus (SRSV) was detected in a stool specimen of a patient during an acute gastroenteritis outbreak in Tokyo and was tentatively named SRSV-9. SRSV-9 was purified by sucrose velocity gradient centrifugation after CsCl density gradient centrifugation. The buoyant density of SRSV-9 appeared to be 1.36 g/ml in CsCl. A Western blot (immunoblot) assay using the biotin-avidin system revealed that SRSV-9 was antigenically related to the Hawaii agent but distinct from the Norwalk agent and contained a single major structural protein with a molecular size of 63.0 +/- 0.6 kilodaltons. The prevalence of SRSV-9 infection in Tokyo was surveyed by the Western blot antibody assay by using a crude virus preparation as the antigen. Seroconversion was observed in 56.5% of the patients involved in the outbreaks from which SRSV was detected by electron microscopy.
Lager, Malin; Mernelius, Sara; Löfgren, Sture; Söderman, Jan
2016-01-01
Healthcare-associated infections caused by Escherichia coli and antibiotic resistance due to extended-spectrum beta-lactamase (ESBL) production constitute a threat against patient safety. To identify, track, and control outbreaks and to detect emerging virulent clones, typing tools of sufficient discriminatory power that generate reproducible and unambiguous data are needed. A probe based real-time PCR method targeting multiple single nucleotide polymorphisms (SNP) was developed. The method was based on the multi locus sequence typing scheme of Institute Pasteur and by adaptation of previously described typing assays. An 8 SNP-panel that reached a Simpson's diversity index of 0.95 was established, based on analysis of sporadic E. coli cases (ESBL n = 27 and non-ESBL n = 53). This multi-SNP assay was used to identify the sequence type 131 (ST131) complex according to the Achtman's multi locus sequence typing scheme. However, it did not fully discriminate within the complex but provided a diagnostic signature that outperformed a previously described detection assay. Pulsed-field gel electrophoresis typing of isolates from a presumed outbreak (n = 22) identified two outbreaks (ST127 and ST131) and three different non-outbreak-related isolates. Multi-SNP typing generated congruent data except for one non-outbreak-related ST131 isolate. We consider multi-SNP real-time PCR typing an accessible primary generic E. coli typing tool for rapid and uniform type identification.
de Noya, Belkisyolé Alarcón; Díaz-Bello, Zoraida; Colmenares, Cecilia; Ruiz-Guevara, Raiza; Mauriello, Luciano; Muñoz-Calderón, Arturo; Noya, Oscar
2015-01-01
Orally transmitted Chagas disease has become a matter of concern due to outbreaks reported in four Latin American countries. Although several mechanisms for orally transmitted Chagas disease transmission have been proposed, food and beverages contaminated with whole infected triatomines or their faeces, which contain metacyclic trypomastigotes of Trypanosoma cruzi, seems to be the primary vehicle. In 2007, the first recognised outbreak of orally transmitted Chagas disease occurred in Venezuela and largest recorded outbreak at that time. Since then, 10 outbreaks (four in Caracas) with 249 cases (73.5% children) and 4% mortality have occurred. The absence of contact with the vector and of traditional cutaneous and Romana’s signs, together with a florid spectrum of clinical manifestations during the acute phase, confuse the diagnosis of orally transmitted Chagas disease with other infectious diseases. The simultaneous detection of IgG and IgM by ELISA and the search for parasites in all individuals at risk have been valuable diagnostic tools for detecting acute cases. Follow-up studies regarding the microepidemics primarily affecting children has resulted in 70% infection persistence six years after anti-parasitic treatment. Panstrongylus geniculatus has been the incriminating vector in most cases. As a food-borne disease, this entity requires epidemiological, clinical, diagnostic and therapeutic approaches that differ from those approaches used for traditional direct or cutaneous vector transmission. PMID:25946155
Jenkins, Claire; Dallman, Timothy J; Launders, Naomi; Willis, Caroline; Byrne, Lisa; Jorgensen, Frieda; Eppinger, Mark; Adak, Goutam K; Aird, Heather; Elviss, Nicola; Grant, Kathie A; Morgan, Dilys; McLauchlin, Jim
2015-06-15
An increase in the number of cases of Shiga toxin-producing Escherichia coli (STEC) O157 phage type 2 (PT2) in England in September 2013 was epidemiologically linked to watercress consumption. Whole-genome sequencing (WGS) identified a phylogenetically related cluster of 22 cases (outbreak 1). The isolates comprising this cluster were not closely related to any other United Kingdom strain in the Public Health England WGS database, suggesting a possible imported source. A second outbreak of STEC O157 PT2 (outbreak 2) was identified epidemiologically following the detection of outbreak 1. Isolates associated with outbreak 2 were phylogenetically distinct from those in outbreak 1. Epidemiologically unrelated isolates on the same branch as the outbreak 2 cluster included those from human cases in England with domestically acquired infection and United Kingdom domestic cattle. Environmental sampling using PCR resulted in the isolation of STEC O157 PT2 from irrigation water at one implicated watercress farm, and WGS showed this isolate belonged to the same phylogenetic cluster as outbreak 2 isolates. Cattle were in close proximity to the watercress bed and were potentially the source of the second outbreak. Transfer of STEC from the field to the watercress bed may have occurred through wildlife entering the watercress farm or via runoff water. During this complex outbreak investigation, epidemiological studies, comprehensive testing of environmental samples, and the use of novel molecular methods proved invaluable in demonstrating that two simultaneous outbreaks of STEC O157 PT2 were both linked to the consumption of watercress but were associated with different sources of contamination. Copyright © 2015, American Society for Microbiology. All Rights Reserved.
Dallman, Timothy J.; Launders, Naomi; Willis, Caroline; Byrne, Lisa; Jorgensen, Frieda; Eppinger, Mark; Adak, Goutam K.; Aird, Heather; Elviss, Nicola; Grant, Kathie A.; Morgan, Dilys; McLauchlin, Jim
2015-01-01
An increase in the number of cases of Shiga toxin-producing Escherichia coli (STEC) O157 phage type 2 (PT2) in England in September 2013 was epidemiologically linked to watercress consumption. Whole-genome sequencing (WGS) identified a phylogenetically related cluster of 22 cases (outbreak 1). The isolates comprising this cluster were not closely related to any other United Kingdom strain in the Public Health England WGS database, suggesting a possible imported source. A second outbreak of STEC O157 PT2 (outbreak 2) was identified epidemiologically following the detection of outbreak 1. Isolates associated with outbreak 2 were phylogenetically distinct from those in outbreak 1. Epidemiologically unrelated isolates on the same branch as the outbreak 2 cluster included those from human cases in England with domestically acquired infection and United Kingdom domestic cattle. Environmental sampling using PCR resulted in the isolation of STEC O157 PT2 from irrigation water at one implicated watercress farm, and WGS showed this isolate belonged to the same phylogenetic cluster as outbreak 2 isolates. Cattle were in close proximity to the watercress bed and were potentially the source of the second outbreak. Transfer of STEC from the field to the watercress bed may have occurred through wildlife entering the watercress farm or via runoff water. During this complex outbreak investigation, epidemiological studies, comprehensive testing of environmental samples, and the use of novel molecular methods proved invaluable in demonstrating that two simultaneous outbreaks of STEC O157 PT2 were both linked to the consumption of watercress but were associated with different sources of contamination. PMID:25841005
Integrating Remote Sensing and Disease Surveillance to Forecast Malaria Epidemics
NASA Astrophysics Data System (ADS)
Wimberly, M. C.; Beyane, B.; DeVos, M.; Liu, Y.; Merkord, C. L.; Mihretie, A.
2015-12-01
Advance information about the timing and locations of malaria epidemics can facilitate the targeting of resources for prevention and emergency response. Early detection methods can detect incipient outbreaks by identifying deviations from expected seasonal patterns, whereas early warning approaches typically forecast future malaria risk based on lagged responses to meteorological factors. A critical limiting factor for implementing either of these approaches is the need for timely and consistent acquisition, processing and analysis of both environmental and epidemiological data. To address this need, we have developed EPIDEMIA - an integrated system for surveillance and forecasting of malaria epidemics. The EPIDEMIA system includes a public health interface for uploading and querying weekly surveillance reports as well as algorithms for automatically validating incoming data and updating the epidemiological surveillance database. The newly released EASTWeb 2.0 software application automatically downloads, processes, and summaries remotely-sensed environmental data from multiple earth science data archives. EASTWeb was implemented as a component of the EPIDEMIA system, which combines the environmental monitoring data and epidemiological surveillance data into a unified database that supports both early detection and early warning models. Dynamic linear models implemented with Kalman filtering were used to carry out forecasting and model updating. Preliminary forecasts have been disseminated to public health partners in the Amhara Region of Ethiopia and will be validated and refined as the EPIDEMIA system ingests new data. In addition to continued model development and testing, future work will involve updating the public health interface to provide a broader suite of outbreak alerts and data visualization tools that are useful to our public health partners. The EPIDEMIA system demonstrates a feasible approach to synthesizing the information from epidemiological surveillance systems and remotely-sensed environmental monitoring systems to improve malaria epidemic detection and forecasting.
SEARCHING FOR A WATER SUPPLY CONNECTION IN THE CABOOL, MISSOURI OUTBREAK
A recent disease outbreak resulting in 4 deaths, 32 hospitalization and a total of 243 documented cases of diarrhea was linked epidemiologically and by on-site data gathering supported by the use of a distribution system model to the public water supply. The pathogenic agent, Esc...
Weiser, Armin A; Thöns, Christian; Filter, Matthias; Falenski, Alexander; Appel, Bernd; Käsbohrer, Annemarie
2016-01-01
FoodChain-Lab is modular open-source software for trace-back and trace-forward analysis in food-borne disease outbreak investigations. Development of FoodChain-Lab has been driven by a need for appropriate software in several food-related outbreaks in Germany since 2011. The software allows integrated data management, data linkage, enrichment and visualization as well as interactive supply chain analyses. Identification of possible outbreak sources or vehicles is facilitated by calculation of tracing scores for food-handling stations (companies or persons) and food products under investigation. The software also supports consideration of station-specific cross-contamination, analysis of geographical relationships, and topological clustering of the tracing network structure. FoodChain-Lab has been applied successfully in previous outbreak investigations, for example during the 2011 EHEC outbreak and the 2013/14 European hepatitis A outbreak. The software is most useful in complex, multi-area outbreak investigations where epidemiological evidence may be insufficient to discriminate between multiple implicated food products. The automated analysis and visualization components would be of greater value if trading information on food ingredients and compound products was more easily available.
Filter, Matthias; Falenski, Alexander; Appel, Bernd; Käsbohrer, Annemarie
2016-01-01
FoodChain-Lab is modular open-source software for trace-back and trace-forward analysis in food-borne disease outbreak investigations. Development of FoodChain-Lab has been driven by a need for appropriate software in several food-related outbreaks in Germany since 2011. The software allows integrated data management, data linkage, enrichment and visualization as well as interactive supply chain analyses. Identification of possible outbreak sources or vehicles is facilitated by calculation of tracing scores for food-handling stations (companies or persons) and food products under investigation. The software also supports consideration of station-specific cross-contamination, analysis of geographical relationships, and topological clustering of the tracing network structure. FoodChain-Lab has been applied successfully in previous outbreak investigations, for example during the 2011 EHEC outbreak and the 2013/14 European hepatitis A outbreak. The software is most useful in complex, multi-area outbreak investigations where epidemiological evidence may be insufficient to discriminate between multiple implicated food products. The automated analysis and visualization components would be of greater value if trading information on food ingredients and compound products was more easily available. PMID:26985673
Banko, Paul C.; Peck, Robert W.; Yelenik, Stephanie G.; Paxton, Eben H.; Bonaccorso, Frank J.; Montoya-Aiona, Kristina; Foote, David
2014-01-01
A massive outbreak of the koa moth (Geometridea: Scotorythra paludicola) defoliated more than a third of the koa (Acacia koa) forest on Hawai‘i Island during 2013−2014. This was the largest koa moth outbreak ever recorded and the first on the island since 1953. The outbreak spread to sites distributed widely around the island between 800−2,000 m elevation and in wet rainforest to dry woodland habitats. We monitored the outbreak at two windward forest sites (Laupāhoehoe and Saddle Road Kīpuka) and one leeward forest site (Kona), and we studied the dynamics of the outbreak and its impacts on the forest ecosystem at Hakalau Forest National Wildlife Refuge, our higher elevation windward site. Study sites at Hakalau included two stands of koa that were planted (reforestation stands) in former cattle pastureland about 20 years earlier and two stands of koa that were dominated by ‘ōhi‘a (Metrosideros polymorpha) and that were naturally recovering from cattle grazing (forest stands). We observed one outbreak at Hakalau, multiple outbreaks at the two other windward sites, but no outbreak at the leeward site. Caterpillars at Hakalau reached peak estimated abundances of more than 250,000 per tree and 18,000,000 per hectare, and they removed between 64−93% of the koa canopy in managed forest stands. Defoliation was more extensive in naturally recovering forest, where ‘ōhi‘a dominated and koa was less abundant, compared to the planted stands, where koa density was high. Koa trees were still growing new foliage six months after being defoliated, and leaves were produced in greater proportion to phyllodes, especially by small koa (≤ 8 cm dbh) and by larger trees in forest stands, where light levels may have remained relatively low after defoliation due to the high cover of ‘ōhi‘a. Small branches of many trees apparently died, and canopy regrowth was absent or low in 9% of koa trees and seedlings, which indicates the likely level of mortality. Between 2,000−5,000 kg/ha of frass fell during the defoliation event, resulting in the deposition of up to 200 kg/ha of highly labile nitrogen on the forest floor in less than two months. The deposition of nitrogen was detected as pulses in resin-available nitrogen in the top 5−10 cm of soil at two of three sites. These sites showed elevated soil nitrogen for about seven months. Nitrogen content of understory plant foliage, which is indicative of nitrogen uptake, suggested weak and variable effects of nitrogen deposition in the soil. Foliar nitrogen increased slightly in alien pasture grasses four months after the deposition of frass, although distinctive increases were not detected in native woody species. Birds responded to the abundance of caterpillars by increasing their activity in koa during the buildup of caterpillars and decreasing their use of koa after defoliation. During the outbreak, caterpillars increased in the diets of the two generalist insectivores we examined, and nearly all species gained weight. Bats responded to the abundance of moths by compression of active foraging into the first three hours of darkness each night after presumably having reached a digestive bottleneck. Reduced foraging activity by bats also resulted in lower indices of detectability based upon acoustic monitoring when compared to non-outbreak years. Parasitoid wasps tracked caterpillar abundance, but the low rate at which they attacked caterpillars suggests that they had little influence on the population. The predatory yellowjacket (Vespula pensylvanica) did not respond to the outbreak. Although a single, protracted outbreak occurred at Hakalau, multiple outbreaks and defoliations occurred at lower elevations. Our results provide a broad foundation for evaluating the dynamics and impacts of future Scotorythra outbreaks.
Weaver, J Todd; Malladi, Sasidhar; Goldsmith, Timothy J; Hueston, Will; Hennessey, Morgan; Lee, Brendan; Voss, Shauna; Funk, Janel; Der, Christina; Bjork, Kathe E; Clouse, Timothy L; Halvorson, David A
2012-12-01
Early detection of highly pathogenic avian influenza (HPAI) infection in commercial poultry flocks is a critical component of outbreak control. Reducing the time to detect HPAI infection can reduce the risk of disease transmission to other flocks. The timeliness of different types of detection triggers could be dependent on clinical signs that are first observed in a flock, signs that might vary due to HPAI virus strain characteristics. We developed a stochastic disease transmission model to evaluate how transmission characteristics of various HPAI strains might effect the relative importance of increased mortality, drop in egg production, or daily real-time reverse transcriptase (RRT)-PCR testing, toward detecting HPAI infection in a commercial table-egg layer flock. On average, daily RRT-PCR testing resulted in the shortest time to detection (from 3.5 to 6.1 days) depending on the HPAI virus strain and was less variable over a range of transmission parameters compared with other triggers evaluated. Our results indicate that a trigger to detect a drop in egg production would be useful for HPAI virus strains with long infectious periods (6-8 days) and including an egg-drop detection trigger in emergency response plans would lead to earlier and consistent reporting in some cases. We discuss implications for outbreak control and risk of HPAI spread attributed to different HPAI strain characteristics where an increase in mortality or a drop in egg production or both would be among the first clinical signs observed in an infected flock.
Kaewkungwal, Jaranit; Khamsiriwatchara, Amnat; Sovann, Ly; Sreng, Bun; Phommasack, Bounlay; Kitthiphong, Viengsavanh; Lwin Nyein, Soe; Win Myint, Nyan; Dang Vung, Nguyen; Hung, Pham; S. Smolinski, Mark; W. Crawley, Adam; Ko Oo, Moe
2018-01-01
Cross-border disease transmission is a key challenge for prevention and control of outbreaks. Variation in surveillance structure and national guidelines used in different countries can affect their data quality and the timeliness of outbreak reports. This study aimed to evaluate timeliness and data quality of national outbreak reporting for four countries in the Mekong Basin Disease Surveillance network (MBDS). Data on disease outbreaks occurring from 2010 to 2015 were obtained from the national disease surveillance reports of Cambodia, Lao PDR, Myanmar, and Vietnam. Data included total cases, geographical information, and dates at different timeline milestones in the outbreak detection process. Nine diseases or syndromes with public health importance were selected for the analysis including: dengue, food poisoning & diarrhea, severe diarrhea, diphtheria, measles, H5N1 influenza, H1N1 influenza, rabies, and pertussis. Overall, 2,087 outbreaks were reported from the four countries. The number of outbreaks and number of cases per outbreak varied across countries and diseases, depending in part on the outbreak definition used in each country. Dates on index onset, report, and response were >95% complete in all countries, while laboratory confirmation dates were 10%-100% incomplete in most countries. Inconsistent and out of range date data were observed in 1%-5% of records. The overall timeliness of outbreak report, response, and public communication was within 1–15 days, depending on countries and diseases. Diarrhea and severe diarrhea outbreaks showed the most rapid time to report and response, whereas diseases such as rabies, pertussis and diphtheria required a longer time to report and respond. The hierarchical structure of the reporting system, data collection method, and country’s resources could affect the data quality and timeliness of the national outbreak reporting system. Differences in data quality and timeliness of outbreak reporting system among member countries should be considered when planning data sharing strategies within a regional network. PMID:29694372
1994-11-11
Recent reports of bubonic and pneumonic plague outbreaks in India (1,2) prompted the New York City Department of Health (NYCDOH) and the New York State Department of Health (NYSDOH), in conjunction with CDC, to develop an emergency response plan to detect and manage suspected cases imported by international air travel. This report describes the surveillance system implemented by CDC on September 27 and supplemental efforts by NYC/NYSDOH to guide and inform physicians about the outbreak, and summarizes clinical findings for 11 travelers who had symptoms suggestive of plague.
mei, Hong; Li, Hong; ga, Dan zeng gong; jie, Guo; chi, Mi ma bu; Zhang, Sheng; Ma, Chaofeng
2017-01-01
From April to November 2016, two outbreaks of epidemic keratoconjunctivitis (EKC) occurred successively at primary and middle schools in the Tibet Autonomous Region of China, and a total of 197 clinically diagnosed cases were reported. Real-time PCR analyses confirmed that human adenovirus (HAdV) infection was related to these outbreaks. Further studies involving sequence determination and phylogenetic analysis based on the penton base, hexon, and fiber genes indicated that human adenovirus type 8 (HAdV-8), belonging to species D, was responsible for the outbreaks. This is the first report of a HAdV-8 associated EKC outbreak in mainland of China, and the results of this study are expected to provide support for future research into HAdV-8 in China. PMID:28915257
Pseudo-outbreak of Penicillium in an outpatient obstetrics and gynecology clinic.
Sood, Geetika; Huber, Kerri; Dam, Lisa; Riedel, Stefan; Grubb, Lisa; Zenilman, Jonathan; Perl, Trish M; Argani, Cynthia
2017-05-01
We report an unusual pseudo-outbreak of Penicillium that occurred in patients seen in an outpatient obstetrics and gynecology clinic. The pseudo-outbreak was detected in late 2012, when the microbiology department reported a series of vaginal cultures positive for Penicillium spp. Our investigation found Penicillium spp in both patient and environmental samples and was potentially associated with the practice of wetting gloves with tap water by a health care worker prior to patient examination. Copyright © 2017 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.
Optimizing surveillance for livestock disease spreading through animal movements
Bajardi, Paolo; Barrat, Alain; Savini, Lara; Colizza, Vittoria
2012-01-01
The spatial propagation of many livestock infectious diseases critically depends on the animal movements among premises; so the knowledge of movement data may help us to detect, manage and control an outbreak. The identification of robust spreading features of the system is however hampered by the temporal dimension characterizing population interactions through movements. Traditional centrality measures do not provide relevant information as results strongly fluctuate in time and outbreak properties heavily depend on geotemporal initial conditions. By focusing on the case study of cattle displacements in Italy, we aim at characterizing livestock epidemics in terms of robust features useful for planning and control, to deal with temporal fluctuations, sensitivity to initial conditions and missing information during an outbreak. Through spatial disease simulations, we detect spreading paths that are stable across different initial conditions, allowing the clustering of the seeds and reducing the epidemic variability. Paths also allow us to identify premises, called sentinels, having a large probability of being infected and providing critical information on the outbreak origin, as encoded in the clusters. This novel procedure provides a general framework that can be applied to specific diseases, for aiding risk assessment analysis and informing the design of optimal surveillance systems. PMID:22728387
Benedict, Katharine M; Reses, Hannah; Vigar, Marissa; Roth, David M; Roberts, Virginia A; Mattioli, Mia; Cooley, Laura A; Hilborn, Elizabeth D; Wade, Timothy J; Fullerton, Kathleen E; Yoder, Jonathan S; Hill, Vincent R
2017-11-10
Provision of safe water in the United States is vital to protecting public health (1). Public health agencies in the U.S. states and territories* report information on waterborne disease outbreaks to CDC through the National Outbreak Reporting System (NORS) (https://www.cdc.gov/healthywater/surveillance/index.html). During 2013-2014, 42 drinking water-associated † outbreaks were reported, accounting for at least 1,006 cases of illness, 124 hospitalizations, and 13 deaths. Legionella was associated with 57% of these outbreaks and all of the deaths. Sixty-nine percent of the reported illnesses occurred in four outbreaks in which the etiology was determined to be either a chemical or toxin or the parasite Cryptosporidium. Drinking water contamination events can cause disruptions in water service, large impacts on public health, and persistent community concern about drinking water quality. Effective water treatment and regulations can protect public drinking water supplies in the United States, and rapid detection, identification of the cause, and response to illness reports can reduce the transmission of infectious pathogens and harmful chemicals and toxins.
Outbreak of Salmonella Oslo Infections Linked to Persian Cucumbers - United States, 2016.
Bottichio, Lyndsay; Medus, Carlota; Sorenson, Alida; Donovan, Danielle; Sharma, Reeti; Dowell, Natasha; Williams, Ian; Wellman, Allison; Jackson, Alikeh; Tolar, Beth; Griswold, Taylor; Basler, Colin
2016-12-30
In April 2016, PulseNet, the national molecular subtyping network for foodborne disease surveillance, detected a multistate cluster of Salmonella enterica serotype Oslo infections with an indistinguishable pulsed-field gel electrophoresis (PFGE) pattern (XbaI PFGE pattern OSLX01.0090).* This PFGE pattern was new in the database; no previous infections or outbreaks have been identified. CDC, state and local health and agriculture departments and laboratories, and the Food and Drug Administration (FDA) conducted epidemiologic, traceback, and laboratory investigations to identify the source of this outbreak. A total of 14 patients in eight states were identified, with illness onsets occurring during March 21-April 9, 2016. Whole genome sequencing, a highly discriminating subtyping method, was used to further characterize PFGE pattern OSLX01.0090 isolates. Epidemiologic evidence indicates Persian cucumbers as the source of Salmonella Oslo infections in this outbreak. This is the fourth identified multistate outbreak of salmonellosis associated with cucumbers since 2013. Further research is needed to understand the mechanism and factors that contribute to contamination of cucumbers during growth, harvesting, and processing to prevent future outbreaks.
Mohtashemi, Mojdeh; Szolovits, Peter; Dunyak, James; Mandl, Kenneth D.
2013-01-01
The threat of biological warfare and the emergence of new infectious agents spreading at a global scale have highlighted the need for major enhancements to the public health infrastructure. Early detection of epidemics of infectious diseases requires both real-time data and real-time interpretation of data. Despite moderate advancements in data acquisition, the state of the practice for real-time analysis of data remains inadequate. We present a nonlinear mathematical framework for modeling the transient dynamics of influenza, applied to historical data sets of patients with influenza-like illness. We estimate the vital time-varying epidemiological parameters of infections from historical data, representing normal epidemiological trends. We then introduce simulated outbreaks of different shapes and magnitudes into the historical data, and estimate the parameters representing the infection rates of anomalous deviations from normal trends. Finally, a dynamic threshold-based detection algorithm is devised to assess the timeliness and sensitivity of detecting the irregularities in the data, under a fixed low false-positive rate. We find that the detection algorithm can identify such designated abnormalities in the data with high sensitivity with specificity held at 97%, but more importantly, early during an outbreak. The proposed methodology can be applied to a broad range of influenza-like infectious diseases, whether naturally occurring or a result of bioterrorism, and thus can be an integral component of a real-time surveillance system. PMID:16556450
Factors That Influence the Transmission of West Nile Virus in Florida.
Day, Jonathan F; Tabachnick, Walter J; Smartt, Chelsea T
2015-09-01
West Nile virus (WNV) was first detected in North America in New York City during the late summer of 1999 and was first detected in Florida in 2001. Although WNV has been responsible for widespread and extensive epidemics in human populations and epizootics in domestic animals and wildlife throughout North America, comparable epidemics have never materialized in Florida. Here, we review some of the reasons why WNV has yet to cause an extensive outbreak in Florida. The primary vector of mosquito-borne encephalitis virus in Florida is Culex nigripalpus Theobald. Rainfall, drought, and temperature are the primary factors that regulate annual populations of this species. Cx. nigripalpus is a competent vector of WNV, St. Louis encephalitis virus, and eastern equine encephalitis virus in Florida, and populations of this species can support focal amplification and transmission of these arboviruses. We propose that a combination of environmental factors influencing Cx. nigripalpus oviposition, blood-feeding behavior, and vector competence have limited WNV transmission in Florida to relatively small focal outbreaks and kept the state free of a major epidemic. Florida must remain vigilant to the danger from WNV, because a change in these environmental factors could easily result in a substantial WNV epidemic rivaling those seen elsewhere in the United States. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Braeye, T; DE Schrijver, K; Wollants, E; van Ranst, M; Verhaegen, J
2015-03-01
SUMMARY On 6 December 2010 a fire in Hemiksem, Belgium, was extinguished by the fire brigade with both river water and tap water. Local physicians were asked to report all cases of gastroenteritis. We conducted a retrospective cohort study among 1000 randomly selected households. We performed a statistical and geospatial analysis. Human stool samples, tap water and river water were tested for pathogens. Of the 1185 persons living in the 528 responding households, 222 (18·7%) reported symptoms of gastroenteritis during the time period 6-13 December. Drinking tap water was significantly associated with an increased risk for gastroenteritis (relative risk 3·67, 95% confidence interval 2·86-4·70) as was place of residence. Campylobacter sp. (2/56), norovirus GI and GII (11/56), rotavirus (1/56) and Giardia lamblia (3/56) were detected in stool samples. Tap water samples tested positive for faecal indicator bacteria and protozoa. The results support the hypothesis that a point-source contamination of the tap water with river water was the cause of the multi-pathogen waterborne outbreak.
Bats and zoonotic viruses: can we confidently link bats with emerging deadly viruses?
Moratelli, Ricardo; Calisher, Charles H
2015-01-01
An increasingly asked question is 'can we confidently link bats with emerging viruses?'. No, or not yet, is the qualified answer based on the evidence available. Although more than 200 viruses - some of them deadly zoonotic viruses - have been isolated from or otherwise detected in bats, the supposed connections between bats, bat viruses and human diseases have been raised more on speculation than on evidence supporting their direct or indirect roles in the epidemiology of diseases (except for rabies). However, we are convinced that the evidence points in that direction and that at some point it will be proved that bats are competent hosts for at least a few zoonotic viruses. In this review, we cover aspects of bat biology, ecology and evolution that might be relevant in medical investigations and we provide a historical synthesis of some disease outbreaks causally linked to bats. We provide evolutionary-based hypotheses to tentatively explain the viral transmission route through mammalian intermediate hosts and to explain the geographic concentration of most outbreaks, but both are no more than speculations that still require formal assessment. PMID:25742261
Label-free detection of salmonella typhimurium with ssDNA aptamers
USDA-ARS?s Scientific Manuscript database
Foodborne pathogen Salmonella enterica is one of the major causes of gastrointestinal infections in human and animals. Conventional detection methods are time consuming and not effective enough under emergency circumstances to control outbreaks immediately. Therefore, biosensors that can detect Salm...
Detection of Staphylococcal Enterotoxin in Food
Casman, Ezra P.; Bennett, Reginald W.
1965-01-01
Methods are described for the extraction and serological detection of trace amounts of enterotoxins A and B in foods incriminated in outbreaks of staphylococcal food poisoning. Evidence is presented for the probable applicability of the methods for the detection of unidentified enterotoxins. PMID:14325876
Zachariah, Rony; Woldeyohannes, Desalegn; Bangoura, Adama; Chérif, Gba-Foromo; Loua, Francis; Hermans, Veerle; Tayler-Smith, Katie; Sikhondze, Welile; Camara, Lansana-Mady
2016-01-01
Setting Ten targeted health facilities supported by Damien Foundation (a Belgian Non Governmental Organization) and the National Tuberculosis (TB) Program in Conakry, Guinea. Objectives To uphold TB program performance during the Ebola outbreak in the presence of a package of pre-emptive additional measures geared at reinforcing the routine TB program, and ensuring Ebola infection control, health-workers safety and motivation. Design A retrospective comparative cohort study of a TB program assessing the performance before (2013) and during the (2014) Ebola outbreak. Results During the Ebola outbreak, all health facilities were maintained opened, there were no reported health-worker Ebola infections, drug stockouts or health staff absences. Of 2,475 presumptive pulmonary TB cases, 13% were diagnosed with TB in both periods (160/1203 in 2013 and 163/1272 in 2014). For new TB, treatment success improved from 84% before to 87% during the Ebola outbreak (P = 0.03). Adjusted Hazard-ratios (AHR) for an unfavorable outcome was alwo lower during the Ebola outbreak, AHR = 0.8, 95% CI:0.7–0.9, P = 0.04). Treatment success improved for HIV co-infected patients (72% to 80%, P<0.01). For retreatment patients, the proportion achieving treatment success was maintained (68% to 72%, P = 0.05). Uptake of HIV-testing and Cotrimoxazole Preventive Treatment was maintained over 85%, and Anti-Retroviral Therapy uptake increased from 77% in 2013 to 86% in 2014 (P<0.01). Conclusion Contingency planning and health system and worker support during the 2014 Ebola outbreak was associated with encouraging and sustained TB program performance. This is of relevance to future outbreaks. PMID:27533499
Surface Sampling and Detection Investigations at the CDC
NASA Astrophysics Data System (ADS)
Rose, L. J.; Coulliette, A. D.
2015-03-01
The Environmental and Applied Microbiology Team is tasked with investigating disease outbreaks in healthcare settings. We will summarize and discuss applied research endeavors to understand and optimize sampling and detection of microorganisms.
Lapierre, Pascal; Nazarian, Elizabeth; Zhu, Yan; Wroblewski, Danielle; Saylors, Amy; Passaretti, Teresa; Hughes, Scott; Tran, Anthony; Lin, Ying; Kornblum, John; Morrison, Shatavia S; Mercante, Jeffrey W; Fitzhenry, Robert; Weiss, Don; Raphael, Brian H; Varma, Jay K; Zucker, Howard A; Rakeman, Jennifer L; Musser, Kimberlee A
2017-11-01
During the summer of 2015, New York, New York, USA, had one of the largest and deadliest outbreaks of Legionnaires' disease in the history of the United States. A total of 138 cases and 16 deaths were linked to a single cooling tower in the South Bronx. Analysis of environmental samples and clinical isolates showed that sporadic cases of legionellosis before, during, and after the outbreak could be traced to a slowly evolving, single-ancestor strain. Detection of an ostensibly virulent Legionella strain endemic to the Bronx community suggests potential risk for future cases of legionellosis in the area. The genetic homogeneity of the Legionella population in this area might complicate investigations and interpretations of future outbreaks of Legionnaires' disease.
Nazarian, Elizabeth; Zhu, Yan; Wroblewski, Danielle; Saylors, Amy; Passaretti, Teresa; Hughes, Scott; Tran, Anthony; Lin, Ying; Kornblum, John; Morrison, Shatavia S.; Mercante, Jeffrey W.; Fitzhenry, Robert; Weiss, Don; Raphael, Brian H.; Varma, Jay K.; Zucker, Howard A.; Rakeman, Jennifer L.; Musser, Kimberlee A.
2017-01-01
During the summer of 2015, New York, New York, USA, had one of the largest and deadliest outbreaks of Legionnaires’ disease in the history of the United States. A total of 138 cases and 16 deaths were linked to a single cooling tower in the South Bronx. Analysis of environmental samples and clinical isolates showed that sporadic cases of legionellosis before, during, and after the outbreak could be traced to a slowly evolving, single-ancestor strain. Detection of an ostensibly virulent Legionella strain endemic to the Bronx community suggests potential risk for future cases of legionellosis in the area. The genetic homogeneity of the Legionella population in this area might complicate investigations and interpretations of future outbreaks of Legionnaires’ disease. PMID:29047425
Marx, James O; Gaertner, Diane J; Smith, Abigail L
2017-09-01
Control of rodent adventitial infections in biomedical research facilities is of extreme importance in assuring both animal welfare and high-quality research results. Sixty-three U.S. institutions participated in a survey reporting the methods used to detect and control these infections and the prevalence of outbreaks from 1 January 2014 through 31 December 2015. These results were then compared with the results of 2 similar surveys published in 1998 and 2008. The results of the current survey demonstrated that the rate of viral outbreaks in mouse colonies was decreasing, particularly in barrier facilities, whereas the prevalence of parasitic outbreaks has remained constant. These results will help our profession focus its efforts in the control of adventitial rodent disease outbreaks to the areas of the greatest needs.
Polio-Like Illness Associated With Outbreak of Upper Respiratory Tract Infection in Children.
Crone, Megan; Tellier, Raymond; Wei, Xing-Chang; Kuhn, Susan; Vanderkooi, Otto G; Kim, Jong; Mah, Jean K; Mineyko, Aleksandra
2016-03-01
Poliomyelitis is a historically devastating neurological complication of poliovirus infection. Poliovirus vaccines have decreased the incidence of poliomyelitis to 209 global cases in 2014, with new cases of acute flaccid myelitis primarily associated with nonpolio enteroviruses. Recently, during outbreaks of enterovirus D68 throughout North America and Europe, cases of acute flaccid myelitis have been reported, suggesting another nonpolio enterovirus associated with acute flaccid myelitis. The authors describe 3 patients diagnosed with acute flaccid myelitis during a province-wide outbreak of enterovirus D68 with the virus detected in 2 of the patients. Given the significant morbidity associated with acute flaccid myelitis and potential for nonpolio enterovirus to cause outbreaks, prompt identification and notification of public health authorities are warranted. © The Author(s) 2015.
An outbreak of food-borne gastroenteritis due to sapovirus among junior high school students.
Usuku, Shuzo; Kumazaki, Makoto; Kitamura, Katsuhiko; Tochikubo, Osamu; Noguchi, Yuzo
2008-11-01
The human sapovirus (SaV) causes acute gastroenteritis mainly in infants and young children. A food-borne outbreak of gastroenteritis associated with SaV occurred among junior high school students in Yokohama, Japan, during and after a study trip. The nucleotide sequences of the partial capsid gene derived from the students exhibited 98% homology to a SaV genogroup IV strain, Hu/Angelholm/SW278/2004/SE, which was isolated from an adult with gastroenteritis in Solna, Sweden. An identical nucleotide sequence was detected from a food handler at the hotel restaurant, suggesting that the causative agent of the outbreak was transmitted from the food handler. This is the first description of a food-borne outbreak associated with the SaV genogroup IV strain in Japan.
[Vancomycin-resistant enterococcus--chronicle of a foretold problem].
Bonten, Marc J M; Willems, Rob J
2012-01-01
There have recently been 12 outbreaks of infection caused by vancomycin-resistant enterococci (VRE) in Dutch hospitals. Although the first VRE outbreaks were reported almost 12 years ago, such outbreaks remained uncommon and the question is why they are occurring now. Based on molecular epidemiological studies we have learned that a subpopulation of Enterococcus faecium, resistant to amoxicillin but susceptible to vancomycin, has become highly endemic in Dutch hospitals in the past 12 years. Initial analyses suggest that several transposons containing vancomycin-resistance genes have been introduced into this population, followed by nosocomial spread. We recommend that hospitals without detected VRE outbreaks screen high-risk patients for the presence of VRE. If transmission has already occurred in many hospitals, it will be extremely difficult (and costly) to eradicate VRE.
Veenemans, J; Overdevest, I T; Snelders, E; Willemsen, I; Hendriks, Y; Adesokan, A; Doran, G; Bruso, S; Rolfe, A; Pettersson, A; Kluytmans, J A J W
2014-07-01
Next-generation sequencing (NGS) has the potential to provide typing results and detect resistance genes in a single assay, thus guiding timely treatment decisions and allowing rapid tracking of transmission of resistant clones. We evaluated the performance of a new NGS assay (Hospital Acquired Infection BioDetection System; Pathogenica) during an outbreak of sequence type 131 (ST131) Escherichia coli infections in a nursing home in The Netherlands. The assay was performed on 56 extended-spectrum-beta-lactamase (ESBL) E. coli isolates collected during 2 prevalence surveys (March and May 2013). Typing results were compared to those of amplified fragment length polymorphism (AFLP), whereby we visually assessed the agreement of the BioDetection phylogenetic tree with clusters defined by AFLP. A microarray was considered the gold standard for detection of resistance genes. AFLP identified a large cluster of 31 indistinguishable isolates on adjacent departments, indicating clonal spread. The BioDetection phylogenetic tree showed that all isolates of this outbreak cluster were strongly related, while the further arrangement of the tree also largely agreed with other clusters defined by AFLP. The BioDetection assay detected ESBL genes in all but 1 isolate (sensitivity, 98%) but was unable to discriminate between ESBL and non-ESBL TEM and SHV beta-lactamases or to specify CTX-M genes by group. The performance of the hospital-acquired infection (HAI) BioDetection System for typing of E. coli isolates compared well with the results of AFLP. Its performance with larger collections from different locations, and for typing of other species, was not evaluated and needs further study. Copyright © 2014, American Society for Microbiology. All Rights Reserved.
Allonso, Diego; Meneses, Marcelo D. F.; Fernandes, Carlos A.; Ferreira, Davis F.; Mohana-Borges, Ronaldo
2014-01-01
Dengue virus (DENV) represents a major threat to public health worldwide. Early DENV diagnosis should not only detect the infection but also identify patients with a higher likelihood to develop severe cases. Previous studies have suggested the potential for NS1 to serve as a viral marker for dengue severity. However, further studies using different sera panels are required to confirm this hypothesis. In this context, we developed a lab-based ELISA to detect and quantitate NS1 protein from the four DENV serotypes and from primary and secondary cases. This approach was used to calculate the circulating NS1 concentration in positive samples. We also tested the NS1 positivity of DENV-positive samples according to the Platelia Dengue NS1 Ag assay. A total of 128 samples were positive for DENV infection and were classified according to the WHO guidelines. The overall NS1 positivity was 68% according to the Platelia assay, whereas all samples were NS1-positive when analyzed with our lab-based ELISA. Fifty-four samples were positive by PCR, revealing a co-circulation of DENV1 and DENV4, and the NS1 positivity for DENV4 samples was lower than that for DENV1. The circulating NS1 concentration ranged from 7 to 284 ng/mL. Our results support previous data indicating the low efficiency of the Platelia assay to detect DENV4 infection. Moreover, this work is the first to analyze NS1 antigenemia using retrospective samples from a Brazilian outbreak. PMID:25412084
Wang, Ruiping; Jiang, Yonggen; Guo, Xiaoqin; Wu, Yiling; Zhao, Genming
2017-01-01
Objective The Chinese Center for Disease Control and Prevention developed the China Infectious Disease Automated-alert and Response System (CIDARS) in 2008. The CIDARS can detect outbreak signals in a timely manner but generates many false-positive signals, especially for diseases with seasonality. We assessed the influence of seasonality on infectious disease outbreak detection performance. Methods Chickenpox surveillance data in Songjiang District, Shanghai were used. The optimized early alert thresholds for chickenpox were selected according to three algorithm evaluation indexes: sensitivity (Se), false alarm rate (FAR), and time to detection (TTD). Performance of selected proper thresholds was assessed by data external to the study period. Results The optimized early alert threshold for chickenpox during the epidemic season was the percentile P65, which demonstrated an Se of 93.33%, FAR of 0%, and TTD of 0 days. The optimized early alert threshold in the nonepidemic season was P50, demonstrating an Se of 100%, FAR of 18.94%, and TTD was 2.5 days. The performance evaluation demonstrated that the use of an optimized threshold adjusted for seasonality could reduce the FAR and shorten the TTD. Conclusions Selection of optimized early alert thresholds based on local infectious disease seasonality could improve the performance of the CIDARS. PMID:28728470
Wang, Ruiping; Jiang, Yonggen; Guo, Xiaoqin; Wu, Yiling; Zhao, Genming
2018-01-01
Objective The Chinese Center for Disease Control and Prevention developed the China Infectious Disease Automated-alert and Response System (CIDARS) in 2008. The CIDARS can detect outbreak signals in a timely manner but generates many false-positive signals, especially for diseases with seasonality. We assessed the influence of seasonality on infectious disease outbreak detection performance. Methods Chickenpox surveillance data in Songjiang District, Shanghai were used. The optimized early alert thresholds for chickenpox were selected according to three algorithm evaluation indexes: sensitivity (Se), false alarm rate (FAR), and time to detection (TTD). Performance of selected proper thresholds was assessed by data external to the study period. Results The optimized early alert threshold for chickenpox during the epidemic season was the percentile P65, which demonstrated an Se of 93.33%, FAR of 0%, and TTD of 0 days. The optimized early alert threshold in the nonepidemic season was P50, demonstrating an Se of 100%, FAR of 18.94%, and TTD was 2.5 days. The performance evaluation demonstrated that the use of an optimized threshold adjusted for seasonality could reduce the FAR and shorten the TTD. Conclusions Selection of optimized early alert thresholds based on local infectious disease seasonality could improve the performance of the CIDARS.