Richer, Lisette; Marois, Paul; Lamontagne, Lucie
We investigated eleven outbreaks of naturally occurring bovine respiratory diseases in calves and adult animals in the St-Hyacinthe area of Quebec. Specific antibodies to bovine herpesvirus-1, bovine viral diarrhea virus, respiratory syncytial virus, parainfluenza type 3 virus, reovirus type 3, and serotypes 1 to 7 of bovine adenovirus were found in paired sera from diseased animals. Several bovine viruses with respiratory tropism were involved concomitantly in herds during an outbreak of bovine respiratory disease. In addition, concomitant fourfold rises of antibody titers were frequently observed to two or more viral agents in seroconverted calves (61%) or adult animals (38%). Bovine viral diarrhea virus was found to be the most frequent viral agent associated with multiple viral infection in calves only (92%). PMID:17423116
Preparing for and responding to outbreaks of serious livestock infectious diseases are critical measures to safeguard animal health, public health, and food supply. Almost all of the current control strategies are empirical, and mass culling or “stamping out” is frequently the principal strategy for controlling epidemics. However, there are ethical, ecological, and economic reasons to consider less drastic control strategies. Here we use modeling to quantitatively study the efficacy of different control measures for viral outbreaks, where the infectiousness, transmissibility and death rate of animals commonly depends on their viral load. We develop a broad theoretical framework for exploring and understanding this heterogeneity. The model includes both direct transmission from infectious animals and indirect transmission from an environmental reservoir. We then incorporate a large variety of control measures, including vaccination, antivirals, isolation, environmental disinfection, and several forms of culling, which may result in fewer culled animals. We provide explicit formulae for the basic reproduction number, R0, for each intervention and for combinations. We evaluate the control methods for a realistic simulated outbreak of low pathogenic avian influenza on a mid-sized turkey farm. In this simulated outbreak, culling results in more total dead birds and dramatically more when culling all of the infected birds. PMID:28187137
Oleribe, Obinna Ositadimma; Crossey, Mary Margaret Elizabeth; Taylor-Robinson, Simon David
The Ebola virus disease outbreak that initially hit Guinea, Liberia and Senegal in 2014 was projected to affect Nigeria very badly when the first case was reported in July 2014. However, the outbreak was effectively and swiftly contained with only eight deaths out of 20 cases, confounding even the most optimistic predictions of the disease modelers. A combination of health worker and public education, a coordinated field epidemiology and laboratory training program (with prior experience in disease outbreak control in other diseases) and effective set-up of emergency operations centers were some of the measures that helped to confound the critics and contain what would have been an otherwise deadly outbreak in a densely populated country with a highly mobile population. This article highlights the measures taken in Nigeria and looks to the translatable lessons learnt for future disease outbreaks, whether that be from the Ebola virus or other infectious agents. PMID:26740841
Gautam, Renu; Mishra, Sweta; Milhotra, Archana; Nagpal, Ritika; Mohan, Mradul; Singhal, Anchal; Kumari, Pratibha
The viruses responsible for mosquito-borne diseases are on an exploring mode, expanding their horizon, adapting to the situation and comfortably making their presence felt globally, from South Africa to Asia, Europe and United States. The current global scenario and recent documentations indicate towards the real monsters, outbreak of Zika, dengue and chikungunya viruses. Zika, dengue and chikungunya viruses, all three are positive sense single-stranded RNA arbovirus and so their initial symptoms are almost 80% similar and all three are spread by mosquitos which bite during the day. Zika virus is more dangerous for pregnant women as it is suspected to cause brain damage in babies by targeting their neuron cells. A less common but highly dangerous type of Dengue is the one which causes hemorrhagic fever (DHF) and shock syndrome (DSS) which are lethal. Chikungunya is not as lethal as Zika and Dengue are, but it triggers joints pain which could last for months and even for years. There is no line of treatment for all three viruses and their vaccines are at different stages of development. The challenges associated with the epidemic wave of Zika, dengue and chikungunya viruses have been explained and the current status of drug/ vaccine development against these viruses has been reviewed.
Chu, Chung-Ming; Cheng, Vincent C C; Hung, Ivan F N; Chan, Kin-Sang; Tang, Bone S F; Tsang, Thomas H F; Chan, Kwok-Hung; Yuen, Kwok-Yung
An unprecedented community outbreak of severe acute respiratory syndrome (SARS) occurred in the Amoy Gardens, a high-rise residential complex in Hong Kong. Droplet, air, contaminated fomites, and rodent pests have been proposed to be mechanisms for transmitting SARS in a short period. We studied nasopharyngeal viral load of SARS patients on admission and their geographic distribution. Higher nasopharyngeal viral load was found in patients living in adjacent units of the same block inhabited by the index patient, while a lower but detectable nasopharyngeal viral load was found in patients living further away from the index patient. This pattern of nasopharyngeal viral load suggested that airborne transmission played an important part in this outbreak in Hong Kong. Contaminated fomites and rodent pests may have also played a role.
Fisher-Hoch, Susan P
The outbreak of Marburg haemorrhagic fever in Angola in 2004-2005 shows once again the devastating and rapid spread of viral haemorrhagic fevers in medical settings where hygiene practices are poorly applied or ignored. The legacy of years of war and poverty in Angola has resulted in very poor medical education and services. The initial high rate of infection among infants in Angola may have been related to poor hospital practices, possibly administration of vaccines. Though the outbreak in Angola was in a part of Africa not previously known to have filovirus infection, prior ecological modelling had predicted this location and many others. Prevention of future outbreaks will not be easy. The urgent need is dissemination of knowledge and the training, discipline and resources for good clinical practice. Educating the public to demand higher standards could be a powerful tool. Good practices are difficult to establish and maintain on the scale needed.
Shaman, J. L.
Dynamic models of infectious disease systems abound and are used to study the epidemiological characteristics of disease outbreaks, the ecological mechanisms affecting transmission, and the suitability of various control and intervention strategies. The dynamics of disease transmission are non-linear and consequently difficult to forecast. Here, we describe combined model-inference frameworks developed for the prediction of infectious diseases. We show that accurate and reliable predictions of seasonal influenza outbreaks can be made using a mathematical model representing population-level influenza transmission dynamics that has been recursively optimized using ensemble data assimilation techniques and real-time estimates of influenza incidence. Operational real-time forecasts of influenza and other infectious diseases have been and are currently being generated.
Presents a literature review of disease outbreaks related to fish and shellfish, covering publications of 1976-77. This review covers the chemical, bacterial, and viral diseases that are transmitted by fish and shellfish. A list of 50 references is also presented. (HM)
The emergence of new, transmissible infections poses a significant threat to human populations. As the 2009 novel influenza A/H1N1 pandemic and the 2014-2015 Ebola epidemic demonstrate, we have observed the effects of rapid spread of illness in non-immune populations and experienced disturbing uncertainty about future potential for human suffering and societal disruption. Clinical and epidemiologic characteristics of a newly emerged infectious organism are usually gathered in retrospect as the outbreak evolves and affects populations. Knowledge of potential effects of outbreaks and epidemics and most importantly, mitigation at community, regional, national and global levels is needed to inform policy that will prepare and protect people. Study of possible outcomes of evolving epidemics and application of mitigation strategies is not possible in observational or experimental research designs, but computational modeling allows conduct of `virtual' experiments. Results of well-designed computer simulations can aid in the selection and implementation of strategies that limit illness and death, and maintain systems of healthcare and other critical resources that are vital to public protection. Mitigating Infectious Disease Outbreaks.
Gulbahce, Natali; Yan, Han; Vidal, Marc; Barabasi, Albert-Laszlo
Viral infections induce multiple perturbations that spread along the links of the biological networks of the host cells. Understanding the impact of these cascading perturbations requires an exhaustive knowledge of the cellular machinery as well as a systems biology approach that reveals how individual components of the cellular system function together. Here we describe an integrative method that provides a new approach to studying virus-human interactions and its correlations with diseases. Our method involves the combined utilization of protein - protein interactions, protein -- DNA interactions, metabolomics and gene - disease associations to build a ``viraldiseasome''. By solely using high-throughput data, we map well-known viral associated diseases and predict new candidate viral diseases. We use microarray data of virus-infected tissues and patient medical history data to further test the implications of the viral diseasome. We apply this method to Epstein-Barr virus and Human Papillomavirus and shed light into molecular development of viral diseases and disease pathways.
Craun, Gunther F.
Presents a literature review of the disease outbreaks caused by drinking polluted water, covering publications of 1976-77. Some of the waterborn outbreaks included are: (1) cholera; (2) gastroenteritis; (3) giardiasis; and (4) typhoid fever and salmonellosis. A list of 66 references is also presented. (HM)
Hedberg, C W; Osterholm, M T
Norwalk virus infection is the epidemiologic prototype for outbreaks of food-borne and waterborne gastroenteritis. Around the world, Norwalk virus and Norwalk-like viruses appear to be major causes of food-borne and waterborne illness. Assessment of the overall significance of viral agents to the epidemiology of food-borne and waterborne illness is hampered by the lack of surveillance throughout much of the world. In areas where food-borne and waterborne illness surveillance is conducted, outbreaks of viral gastroenteritis are underreported because of the lack of availability of routine laboratory services to confirm the viral etiology. Routine use of epidemiologic criteria as an alternative to laboratory confirmation will allow better assessments of the importance of viral gastroenteritis until effective laboratory methods can be widely implemented. Outbreaks of viral gastroenteritis have been propagated by contamination of water supplies, raw foods, and ill food handlers. Controlling an outbreak depends on identifying and removing the source of contamination. The demonstrated occurrence of person-to-person transmission and the likely occurrence of transmission of Norwalk-like viruses by aerosol make it necessary to evaluate the potential for transmission by food handlers and servers in every outbreak, regardless of primary source. PMID:8395330
Aitken, Celia; Jeffries, Donald J.
Viruses are important causes of nosocomial infection, but the fact that hospital outbreaks often result from introduction(s) from community-based epidemics, together with the need to initiate specific laboratory testing, means that there are usually insufficient data to allow the monitoring of trends in incidences. The most important defenses against nosocomial transmission of viruses are detailed and continuing education of staff and strict adherence to infection control policies. Protocols must be available to assist in the management of patients with suspected or confirmed viral infection in the health care setting. In this review, we present details on general measures to prevent the spread of viral infection in hospitals and other health care environments. These include principles of accommodation of infected patients and approaches to good hygiene and patient management. They provide detail on individual viral diseases accompanied in each case with specific information on control of the infection and, where appropriate, details of preventive and therapeutic measures. The important areas of nosocomial infection due to blood-borne viruses have been extensively reviewed previously and are summarized here briefly, with citation of selected review articles. Human prion diseases, which present management problems very different from those of viral infection, are not included. PMID:11432812
Caluwaerts, Séverine; Achar, Jay
Ebola viral disease’s interaction with pregnancy is poorly understood and remains a particular challenge for medical and para-medical personnel responding to an outbreak. This review article is written with the benefit of hindsight and experience from the largest recorded Ebola outbreak in history. We have provided a broad overview of the issues that arise for pregnant women and for the professionals treating them during an Ebola outbreak. The discussion focuses on the specifics of Ebola infection in pregnancy and possible management strategies, including the delivery of an infected woman. We have also discussed the wider challenges posed to pregnant women and their carers during an epidemic, including the identification of suspected Ebola-infected pregnant women and the impact of the disease on pre-existing health services. This paper outlines current practices in the field, as well as highlighting the gaps in our knowledge and the paramount need to protect the health-care workers directly involved in the management of pregnant women. PMID:26457118
Thirty-two waterborne disease outbreaks were reported to the Centers for Disease Control (CDC) and the Environmental Protection Agency in 1981. The outbreaks occurred in 17 states and involved 4430 cases. This was only 64% of the number of outbreaks that were reported in 1980 and...
Singh, J; Aggarwal, N R; Bhattacharjee, J; Prakash, C; Bora, D; Jain, D C; Sharma, R S; Datta, K K
A small localised outbreak of viral hepatitis due to HEV occurred in an educated and well placed community. The overall attack rate was found to be 1.9%; the children and adults were equally affected. No fatality was observed. Five blood samples collected from the cases of jaundice were found negative for Anti HAV IgM, HBsAg and Anti HBc IgM, but positive for Anti HEV. The infection spread by contamination of piped water by sewage system resulting from scarcity of water, intermittent water supply and installation of on-line private booster pumps by the residents. Community action, especially the boiling of drinking water till the quality of piped water improved, restricted jaundice cases to only one incubation period. The outbreak highlights the importance of community behaviour in first precipitating the crisis and then limitating the damage.
McEvoy, M; Blake, W; Brown, D; Green, J; Cartwright, R
Three hundred and seventy-eight passengers reported gastroenteritis during four cruises in the western Mediterranean on consecutive weeks of 1995. The rate at which cases were reported each day increased on the fourth cruise. The ship's owner commissioned an epidemiological investigation from the PHLS Communicable Disease Surveillance Centre. Cases reported explosive vomiting and diarrhoea, which lasted from 24 hours to five days, and were suggestive of viral gastroenteritis. No food handlers reported illness, but enquiries suggested that some had been ill and treated themselves. No bacterial pathogens were isolated from faecal specimens provided by cases or from water, food, and environmental samples taken from the galley. Small round structured viruses (SRSV) were identified by reverse transcriptase polymerase chain reaction in two faecal specimens and one specimen of vomit from people who became ill during the fourth cruise. SRSV was also identified in one faecal specimen by electron microscopy. Environmental inspection revealed inappropriate food handling, hygiene, and storage. During one 24 hour period no chlorine was detectable in the water. A case control study conducted on the fourth cruise sought details of exposure to various foodstuffs, unbottled water, and various parts of the ship. No significant associations were found between illness and any exposures. The evidence strongly suggested a continuing outbreak of SRSV infection transmitted from person to person. Some passengers remained on board for a second week and could have transmitted their infection to new arrivals. The ship was cleared and disinfected at the end of the fourth cruise in order to interrupt transmission. Fewer than 10 cases presented in each of the fifth and sixth cruises.
Freimanis, G L; Di Nardo, A; Bankowska, K; King, D J; Wadsworth, J; Knowles, N J; King, D P
Foot and mouth disease virus (FMDV) is an animal pathogen of global economic significance. Identifying the sources of outbreaks plays an important role in disease control; however, this can be confounded by the ease with which FMDV can spread via movement of infected livestock and animal products, aerosols or fomites, e.g. contaminated persons and objects. As sequencing technologies have advanced, this review highlights the uses of viral genomic data in helping to understand the global distribution and transboundary movements of FMDV, and the role that these approaches have played in control and surveillance programmes. The recent application of next-generation sequencing platforms to address important epidemiological and evolutionary challenges is discussed with particular reference to the advent of 'omics' technologies.
de La Vega, Marc-Antoine; Caleo, Grazia; Audet, Jonathan; Qiu, Xiangguo; Kozak, Robert A.; Brooks, James I.; Kern, Steven; Wolz, Anja; Sprecher, Armand; Greig, Jane; Lokuge, Kamalini; Kargbo, David K.; Kargbo, Brima; Di Caro, Antonino; Grolla, Allen; Kobasa, Darwyn; Strong, James E.; Ippolito, Giuseppe; Van Herp, Michel; Kobinger, Gary P.
BACKGROUND. Ebola virus (EBOV) causes periodic outbreaks of life-threatening EBOV disease in Africa. Historically, these outbreaks have been relatively small and geographically contained; however, the magnitude of the EBOV outbreak that began in 2014 in West Africa has been unprecedented. The aim of this study was to describe the viral kinetics of EBOV during this outbreak and identify factors that contribute to outbreak progression. METHODS. From July to December 2014, one laboratory in Sierra Leone processed over 2,700 patient samples for EBOV detection by quantitative PCR (qPCR). Viremia was measured following patient admission. Age, sex, and approximate time of symptom onset were also recorded for each patient. The data was analyzed using various mathematical models to find trends of potential interest. RESULTS. The analysis revealed a significant difference (P = 2.7 × 10–77) between the initial viremia of survivors (4.02 log10 genome equivalents [GEQ]/ml) and nonsurvivors (6.18 log10 GEQ/ml). At the population level, patient viral loads were higher on average in July than in November, even when accounting for outcome and time since onset of symptoms. This decrease in viral loads temporally correlated with an increase in circulating EBOV-specific IgG antibodies among individuals who were suspected of being infected but shown to be negative for the virus by PCR. CONCLUSIONS. Our results indicate that initial viremia is associated with outcome of the individual and outbreak duration; therefore, care must be taken in planning clinical trials and interventions. Additional research in virus adaptation and the impacts of host factors on EBOV transmission and pathogenesis is needed. PMID:26551677
Malani, Anup; Laxminarayan, Ramanan
The global spread of diseases such as swine flu and SARS highlights the difficult decision governments face when presented with evidence of a local outbreak. Reporting the outbreak may bring medical assistance but is also likely to trigger trade sanctions by countries hoping to contain the disease. Suppressing the information may avoid trade…
Yeşilbağ, Kadir; Förster, Christine; Ozyiğit, M Ozgür; Alpay, Gizem; Tuncer, Pelin; Thiel, Heinz-Jürgen; König, Matthias
During 2007 a disease outbreak occurred in cattle in the Marmara region of western Turkey characterised by severe pneumonia and haemorrhagic enteritis in calves. Cases from three farms at different locations were examined and bovine viral diarrhoea virus (BVDV) isolated in all cases. Phylogenetic characterisation of the virus isolates allocated them in a new cluster tentatively named as BVDV-1r.
Foodborne agents cause an estimated 76 million illnesses annually in the United States. Outbreak surveillance provides insights into the causes of foodborne illness, types of implicated foods, and settings of foodborne infections that can be used in food safety strategies to prevent and control foodborne disease. CDC collects data on foodborne disease outbreaks submitted from all states and territories. This report summarizes epidemiologic data for the 1,097 reported outbreaks occurring during 2007 (the most recent finalized data), which resulted in 21,244 cases of foodborne illness and 18 deaths. Among the 497 foodborne outbreaks with a laboratory-confirmed single etiologic agent reported, norovirus was the most common cause, followed by Salmonella. Among the 18 reported deaths, 11 were attributed to bacterial etiologies (five Salmonella, three Listeria monocytogenes, two Escherichia coli O157:H7, and one Clostridium botulinum), two to viral etiologies (norovirus), and one to a chemical (mushroom toxin). Four deaths occurred in outbreaks with unknown etiologies. Among the 235 outbreaks attributed to a single food commodity, poultry (17%), beef (16%), and leafy vegetables (14%) were most often the cause of illness. Public health, regulatory, and agricultural professionals can use this information when creating targeted control strategies and to support efforts to promote safe food preparation practices among food employees and the public.
Saeed, Umar; Piracha, Zahra Zahid
Pakistan is a developing country that has a population of 190 million people and faces a huge burden of viral diseases. Every year during monsoon season heavy rain fall and lack of disaster management skills potentially increase the transmission of waterborne diseases, vector borne diseases and viral outbreaks. Due to severe flooding, thousands of people lose their lives and millions are displaced each year. In most of the cases the children who lose their family members are forced into illegal professions of begging, child labor and prostitution which make them prone to sexually transmitted infections. Up to date, no scientific study has been conducted nationwide to illustrate epidemiological patterns of waterborne diseases, vector borne diseases and viral epidemics during flash flood. Mosquito sprays would not be a sufficient approach for dengue eradication; mass awareness, larvicide and biological control by Guppy fishes are also effective strategies to overcome dengue problem. International health bodies and non-governmental organizations must take note of this alerting situation and take adequate steps such as financial/medical aid in order to defeat the after-effects of flood.
Saeed, Umar; Piracha, Zahra Zahid
Pakistan is a developing country that has a population of 190 million people and faces a huge burden of viral diseases. Every year during monsoon season heavy rain fall and lack of disaster management skills potentially increase the transmission of waterborne diseases, vector borne diseases and viral outbreaks. Due to severe flooding, thousands of people lose their lives and millions are displaced each year. In most of the cases the children who lose their family members are forced into illegal professions of begging, child labor and prostitution which make them prone to sexually transmitted infections. Up to date, no scientific study has been conducted nationwide to illustrate epidemiological patterns of waterborne diseases, vector borne diseases and viral epidemics during flash flood. Mosquito sprays would not be a sufficient approach for dengue eradication; mass awareness, larvicide and biological control by Guppy fishes are also effective strategies to overcome dengue problem. International health bodies and non-governmental organizations must take note of this alerting situation and take adequate steps such as financial/medical aid in order to defeat the after-effects of flood. PMID:27175353
Pan, Huipeng; Preisser, Evan L; Chu, Dong; Wang, Shaoli; Wu, Qingjun; Carriére, Yves; Zhou, Xuguo; Zhang, Youjun
While the management of biological invasions is often characterized by a series of single-specieg decisions, invasive species exist within larger food webs. These biotic interactions can alter the impact of control/eradication programs and may cause suppression efforts to inadvertently facilitate invasion spread and impact. We document the rapid replacement of the invasive Bemisia Middle East-Asia Minor I (MEAM1) cryptic biotype by the cryptic Mediterranean (MED) biotype throughout China and demonstrate that MED is more tolerant of insecticides and a better vector of tomato yellow leaf curl virus (TYLCV) than MEAMJ. While MEAM1 usually excludes MED under natural conditions, insecticide application reverses the MEAM1-MED competitive hierarchy and allows MED to exclude MEAMI. The insecticide-mediated success of MED has led to TYLCV outbreaks throughout China. Our work strongly supports the hypothesis that insecticide use in China reverses the MEAMl-MED competitive hierarchy and allows MED to displace MEAM1 in managed landscapes. By promoting the dominance of a Bemisia species that is a competent viral vector, insecticides thus increase the spread and impact of TYLCV in heterogeneous agroecosystems.
This article summarizes the discussions and conclusions of a workshop held December 7-8, 1998, to consider the inherent limitations and weaknesses of waterborne outbreak investigations and make recommendations for their improvement. In recent years, an increased number of suspec...
Navia-Gine, Wayra G.; Loaiza, Jose R.; Miller, Matthew J.
Mosquito blood meals provide information about the feeding habits and host preference of potential arthropod-borne disease vectors. Although mosquito-borne diseases are ubiquitous in the Neotropics, few studies in this region have assessed patterns of mosquito-host interactions, especially during actual disease outbreaks. Based on collections made during and after an outbreak of equine viral encephalitis, we identified the source of 338 blood meals from 10 species of mosquitoes from Aruza Abajo, a location in Darien province in eastern Panama. A PCR based method targeting three distinct mitochondrial targets and subsequent DNA sequencing was used in an effort to delineate vector-host relationships. At Aruza Abajo, large domesticated mammals dominated the assemblage of mosquito blood meals while wild bird and mammal species represented only a small portion of the blood meal pool. Most mosquito species fed on a variety of hosts; foraging index analysis indicates that eight of nine mosquito species utilize hosts at similar proportions while a stochastic model suggests dietary overlap among species was greater than would be expected by chance. The results from our null-model analysis of mosquito diet overlap are consistent with the hypothesis that in landscapes where large domestic animals dominate the local biomass, many mosquito species show little host specificity, and feed upon hosts in proportion to their biomass, which may have implications for the role of livestocking patterns in vector-borne disease ecology. PMID:24339965
Kawazoe, Ai; Chanlekha, Hutchatai; Collier, Nigel
Background In recent years, there has been a growth in work on the use of information extraction technologies for tracking disease outbreaks from online news texts, yet publicly available evaluation standards (and associated resources) for this new area of research have been noticeably lacking. Objective This study seeks to create a “gold standard” data set against which to test how accurately disease outbreak information extraction systems can identify the semantics of disease outbreak events. Additionally, we hope that the provision of an annotation scheme (and associated corpus) to the community will encourage open evaluation in this new and growing application area. Methods We developed an annotation scheme for identifying infectious disease outbreak events in news texts. An event─in the context of our annotation scheme─consists minimally of geographical (eg, country and province) and disease name information. However, the scheme also allows for the rich encoding of other domain salient concepts (eg, international travel, species, and food contamination). Results The work resulted in a 200-document corpus of event-annotated disease outbreak reports that can be used to evaluate the accuracy of event detection algorithms (in this case, for the BioCaster biosurveillance online news information extraction system). In the 200 documents, 394 distinct events were identified (mean 1.97 events per document, range 0-25 events per document). We also provide a download script and graphical user interface (GUI)-based event browsing software to facilitate corpus exploration. Conclusion In summary, we present an annotation scheme and corpus that can be used in the evaluation of disease outbreak event extraction algorithms. The annotation scheme and corpus were designed both with the particular evaluation requirements of the BioCaster system in mind as well as the wider need for further evaluation resources in this growing research area. PMID:20876049
Navarro, Carmen; Fenoll, Daniel; García, José; González-Diego, Paulino; Jiménez-Buñuales, Teresa; Rodriguez, Miguel; Lopez, Rosa; Pacheco, Francisco; Ruiz, Joaquín; Segovia, Manuel; Baladrón, Beatriz; Pelaz, Carmen
An explosive outbreak of Legionnaires’ disease occurred in Murcia, Spain, in July 2001. More than 800 suspected cases were reported; 449 of these cases were confirmed, which made this the world’s largest outbreak of the disease reported to date. Dates of onset for confirmed cases ranged from June 26 to July 19 , with a case-fatality rate of 1%. The epidemic curve and geographic pattern from the 600 completed epidemiologic questionnaires indicated an outdoor point-source exposure in the northern part of the city. A case-control study matching 85 patients living outside the city of Murcia with two controls each was undertaken to identify the outbreak source; the epidemiologic investigation implicated the cooling towers at a city hospital. An environmental isolate from these towers with an identical molecular pattern as the clinical isolates was subsequently identified and supported that epidemiologic conclusion. PMID:12967487
Johnson, P. T.
Approximately 40 viruses are known from marine sponges; turbellarian and monogenetic flatworms; cephalopod, bivalve, and gastropod mollusks; nereid polychaetes; and isopod and decapod crustaceans. Most of the viruses can be tentatively assigned to the Herpesviridae, Baculoviridae, Iridoviridae, Adenoviridae, Papovaviridae, Reoviridae, “Birnaviridae”, Bunyaviridae, Rhabdoviridae, and Picornaviridae. Viruslike particles found in oysters might be representatives of the Togaviridae and Retroviridae. Enveloped single-stranded RNA viruses from crustaceans have developmental and morphological characteristics intermediate between families, and some show evidence of relationships to the Paramyxoviridae as well as the Bunyaviridae or Rhabdoviridae. Certain small viruses of shrimp cannot be assigned, even tentatively, to a particular family. Some viruses cause disease in wild and captive hosts, others are associated with disease states but may not be primary instigators, and many occur in apparently normal animals. The frequency of viral disease in natural populations of marine invertebrates is unknown. Several viruses that cause disease in captive animals, with or without experimental intervention, have also been found in diseased wild hosts, including herpeslike viruses of crabs and oysters, iridovirus of octopus, and reolike and bunyalike viruses of crabs. Iridolike viruses have been implicated in massive mortalities of cultured oysters. Baculoviruses, and IHHN virus, which is of uncertain affinities, cause economically damaging diseases in cultured penaeid shrimp. Double or multiple viral infection is common in crabs. For example, a reolike virus and associated rhabdolike virus act synergistically to cause paralytic and fatal disease in Callinectes sapidus. Information on host range, most susceptible stage, and viral latency is available only for viruses of shrimp. One baculovirus attacks five species of New World penaeid shrimp. IHHN virus infects three species of
Vivancos, R; Trainor, E; Oyinloye, A; Keenan, A
We assess the effect of key care quality indicators on viral gastroenteritis outbreaks and control in care homes using mandatory inspection data collected by a non-departmental public body. Outbreak occurrence was associated with care home size but not with overall quality or individual environmental standards. Care home size, hygiene and infection control standard scores were inversely associated with attack rate in residents, whereas delayed reporting to the local public health agency was associated with higher attack rates.
Viral infections of the avian gastrointestinal tract negatively impact poultry production; however, determining the complex etiologies of the viral enteric diseases in poultry has been difficult. Project scientists are continuing to investigate the species specificity, molecular phylogenetics, and p...
Mackenzie, J S; Chua, K B; Daniels, P W; Eaton, B T; Field, H E; Hall, R A; Halpin, K; Johansen, C A; Kirkland, P D; Lam, S K; McMinn, P; Nisbet, D J; Paru, R; Pyke, A T; Ritchie, S A; Siba, P; Smith, D W; Smith, G A; van den Hurk, A F; Wang, L F; Williams, D T
Over the past 6 years, a number of zoonotic and vectorborne viral diseases have emerged in Southeast Asia and the Western Pacific. Vectorborne disease agents discussed in this article include Japanese encephalitis, Barmah Forest, Ross River, and Chikungunya viruses. However, most emerging viruses have been zoonotic, with fruit bats, including flying fox species as the probable wildlife hosts, and these will be discussed as well. The first of these disease agents to emerge was Hendra virus, formerly called equine morbillivirus. This was followed by outbreaks caused by a rabies-related virus, Australian bat lyssavirus, and a virus associated with porcine stillbirths and malformations, Menangle virus. Nipah virus caused an outbreak of fatal pneumonia in pigs and encephalitis in humans in the Malay Peninsula. Most recently, Tioman virus has been isolated from flying foxes, but it has not yet been associated with animal or human disease. Of nonzoonotic viruses, the most important regionally have been enterovirus 71 and HIV.
Mackenzie, J. S.; Chua, K. B.; Daniels, P. W.; Eaton, B. T.; Field, H. E.; Hall, R. A.; Halpin, K.; Johansen, C. A.; Kirkland, P. D.; Lam, S. K.; McMinn, P.; Nisbet, D. J.; Paru, R.; Pyke, A. T.; Ritchie, S. A.; Siba, P.; Smith, D. W.; Smith, G. A.; van den Hurk, A. F.; Wang, L. F.; Williams, D. T.
Over the past 6 years, a number of zoonotic and vectorborne viral diseases have emerged in Southeast Asia and the Western Pacific. Vectorborne disease agents discussed in this article include Japanese encephalitis, Barmah Forest, Ross River, and Chikungunya viruses. However, most emerging viruses have been zoonotic, with fruit bats, including flying fox species as the probable wildlife hosts, and these will be discussed as well. The first of these disease agents to emerge was Hendra virus, formerly called equine morbillivirus. This was followed by outbreaks caused by a rabies-related virus, Australian bat lyssavirus, and a virus associated with porcine stillbirths and malformations, Menangle virus. Nipah virus caused an outbreak of fatal pneumonia in pigs and encephalitis in humans in the Malay Peninsula. Most recently, Tioman virus has been isolated from flying foxes, but it has not yet been associated with animal or human disease. Of nonzoonotic viruses, the most important regionally have been enterovirus 71 and HIV. PMID:11485641
The objective of this study was to describe the outcome of natural bovine viral diarrhea virus (BVDV) infection in a herd of 136 bred heifers. This outbreak was notable in that a total of 36 PI calves were generated. Of the 136 bred heifers, 8 failed to deliver a calf. Eight calves died shortly a...
Hatcher, Eneida L.; Zhdanov, Sergey A.; Bao, Yiming; Blinkova, Olga; Nawrocki, Eric P.; Ostapchuck, Yuri; Schäffer, Alejandro A.; Brister, J. Rodney
The Virus Variation Resource is a value-added viral sequence data resource hosted by the National Center for Biotechnology Information. The resource is located at http://www.ncbi.nlm.nih.gov/genome/viruses/variation/ and includes modules for seven viral groups: influenza virus, Dengue virus, West Nile virus, Ebolavirus, MERS coronavirus, Rotavirus A and Zika virus. Each module is supported by pipelines that scan newly released GenBank records, annotate genes and proteins and parse sample descriptors and then map them to controlled vocabulary. These processes in turn support a purpose-built search interface where users can select sequences based on standardized gene, protein and metadata terms. Once sequences are selected, a suite of tools for downloading data, multi-sequence alignment and tree building supports a variety of user directed activities. This manuscript describes a series of features and functionalities recently added to the Virus Variation Resource. PMID:27899678
Ligon, Grant; Bartram, Jamie
Waterborne disease outbreaks attributed to various pathogens and drinking water system characteristics have adversely affected public health worldwide throughout recorded history. Data from drinking water disease outbreak (DWDO) reports of widely varying breadth and depth were synthesized to investigate associations between outbreak attributes and human health impacts. Among 1519 outbreaks described in 475 sources identified during review of the primarily peer-reviewed, English language literature, most occurred in the U.S., the U.K. and Canada (in descending order). The outbreaks are most frequently associated with pathogens of unknown etiology, groundwater and untreated systems, and catchment realm-associated deficiencies (i.e., contamination events). Relative frequencies of outbreaks by various attributes are comparable with those within other DWDO reviews, with water system size and treatment type likely driving most of the (often statistically-significant at p < 0.05) differences in outbreak frequency, case count and attack rate. Temporal analysis suggests that while implementation of surface (drinking) water management policies is associated with decreased disease burden, further strengthening of related policies is needed to address the remaining burden attributed to catchment and distribution realm-associated deficiencies and to groundwater viral and disinfection-only system outbreaks. PMID:27240387
Taylor, L F; Van Donkersgoed, J; Radostits, O M; Booker, C W; Dubovi, E J; van den Hurk, J V; Janzen, E D
This study describes the epidemiological investigation of an outbreak of mucosal disease that occurred on a ranch in southwestern Saskatchewan. Over a six month period during the fall and winter of 1991-1992,in a herd of 515 beef cattle and 96 bison, 20 yearling cattle from a group of 105 housed in one feedlot pen died from mucosal disease. A further eight yearlings were slaughtered for salvage because they were at risk of dying from mucosal disease. Mucosal disease mortalities were the first observed evidence of fetal infections with bovine viral diarrhea virus in this herd. Animals that died from mucosal disease exhibited signs of ill thrift prior to death. Deaths from mucosal disease were confined to the progeny of one herd of beef cows. Following an outbreak of fetal infection with bovine viral diarrhea virus during 1989-1990, at least 28 (22%) of the 128 calves born from this herd of cows in the spring of 1990 were persistently infected with bovine viral diarrhea virus. However, only one calf born from this herd in 1991, and five calves born from all herds in 1992 were persistently infected. Of the five persistently infected calves born in 1992, three were born to persistently infected replacement heifers born in 1990. These heifers calved without assistance in 1992, but only one of their calves survived past three days of age, and it was persistently infected. In January 1992, 82% of the total herd had reciprocal antibody titers to bovine viral diarrhea virus of >/=1024 which suggested a high level of herd immunity to bovine viral diarrhea virus. Thus, following the outbreak of fetal infection with bovine viral diarrhea virus in 1989-1990, herd immunity to bovine viral diarrhea virus had developed rapidly in the breeding cows and heifers. Subsequently, in the next two years, there was a dramatic decline in the number of calves born persistently infected with bovine viral diarrhea virus.
Tulchinsky, T. H.; Burla, E.; Clayman, M.; Sadik, C.; Brown, A.; Goldberger, S.
Waterborne disease remains a major public health problem in many countries. We report findings on nearly three decades of waterborne disease in Israel and the part these diseases play in the total national burden of enteric disease. During the 1970s and 1980s, Israel's community water supplies were frequently of poor quality according to the microbiological standards at that time, and the country experienced many outbreaks of waterborne enteric disease. New regulations raised water quality standards and made chlorination of community water supplies mandatory, as well as imposing more stringent guidelines on maintaining water sources and distribution systems for both surface water and groundwater. This was followed by improved compliance and water quality, and a marked decline in the number of outbreaks of waterborne disease; no outbreaks were detected between 1992 and 1997. The incidence of waterborne salmonellosis, shigellosis, and typhoid declined markedly as proportions of the total burden of these diseases, but peaked during the time in which there were frequent outbreaks of waterborne disease (1980-85). Long-term trends in the total incidence of reported infectious enteric diseases from all sources, including typhoid, shigellosis, and viral hepatitis (all types) declined, while the total incidence of salmonellosis increased. Mandatory chlorination has had an important impact on improving water quality, in reducing outbreaks of waterborne disease in Israel, and reducing the total burden of enteric disease in the country. PMID:11196499
Li, Melissa K; Beck, Melinda A; Shi, Qing; Harruff, Richard C
We present a group of 18 illegal immigrant stowaways who arrived in a shipboard cargo container suffering from gastroenteritis, dehydration, and malnutrition and showing evidence of viral myocarditis in 3 of 4 fatalities. Our investigation included an evaluation of the 2-week ocean voyage, analysis of medical records and laboratory results of the survivors, autopsies on the decedents, and viral studies on their heart tissue. Of 3 stowaways who died shipboard, 2 showed lymphocytic myocarditis and 1 could not be evaluated histologically due to decomposition. A fourth stowaway died 4 months after arrival with dilated cardiomyopathy and lymphocytic myocarditis. Reverse-transcriptase polymerase chain reaction and nucleotide sequencing of viral isolates from the decedents' heart tissues demonstrated Coxsackie virus B3 genome. We believe that these cases represent an outbreak of viral myocarditis, exacerbated by acute dehydration and malnutrition, due to confinement within the shipping container. Our evidence indicates that close confinement promoted the spread of the virus, and nutritional deprivation increased the stowaways' vulnerability. Furthermore, our observations support the conclusion, based on experimental studies, that nutritionally induced oxidative stress increased the virulence of the etiologic viral agent. In summary, these cases represent a potential infectious disease hazard of illegal immigration.
Foodborne agents cause an estimated 48 million illnesses annually in the United States, including 9.4 million illnesses from known pathogens. CDC collects data on foodborne disease outbreaks submitted from all states and territories through the Foodborne Disease Outbreak Surveillance System. During 2008, the most recent year for which data are finalized, 1,034 foodborne disease outbreaks were reported, which resulted in 23,152 cases of illness, 1,276 hospitalizations, and 22 deaths. Among the 479 outbreaks with a laboratory-confirmed single etiologic agent reported, norovirus was the most common, accounting for 49% of outbreaks and 46% of illnesses. Salmonella was the second most common, accounting for 23% of outbreaks and 31% of illnesses. Among the 218 outbreaks attributed to a food vehicle with ingredients from only one of 17 defined food commodities, the top commodities to which outbreaks were attributed were poultry (15%), beef (14%), and finfish (14%), whereas the top commodities to which outbreak-related illnesses were attributed were fruits and nuts (24%), vine-stalk vegetables (23%), and beef (13%). Outbreak surveillance provides insights into the agents that cause foodborne illness, types of implicated foods, and settings where transmission occurs. Public health, regulatory, and food industry professionals can use this information to target prevention efforts against pathogens and foods that cause the most foodborne disease outbreaks.
McMichael, Anthony J
Human-driven climatic changes will fundamentally influence patterns of human health, including infectious disease clusters and epidemics following extreme weather events. Extreme weather events are projected to increase further with the advance of human-driven climate change. Both recent and historical experiences indicate that infectious disease outbreaks very often follow extreme weather events, as microbes, vectors and reservoir animal hosts exploit the disrupted social and environmental conditions of extreme weather events. This review article examines infectious disease risks associated with extreme weather events; it draws on recent experiences including Hurricane Katrina in 2005 and the 2010 Pakistan mega-floods, and historical examples from previous centuries of epidemics and 'pestilence' associated with extreme weather disasters and climatic changes. A fuller understanding of climatic change, the precursors and triggers of extreme weather events and health consequences is needed in order to anticipate and respond to the infectious disease risks associated with human-driven climate change. Post-event risks to human health can be constrained, nonetheless, by reducing background rates of persistent infection, preparatory action such as coordinated disease surveillance and vaccination coverage, and strengthened disaster response. In the face of changing climate and weather conditions, it is critically important to think in ecological terms about the determinants of health, disease and death in human populations.
McMichael, Anthony J
Human-driven climatic changes will fundamentally influence patterns of human health, including infectious disease clusters and epidemics following extreme weather events. Extreme weather events are projected to increase further with the advance of human-driven climate change. Both recent and historical experiences indicate that infectious disease outbreaks very often follow extreme weather events, as microbes, vectors and reservoir animal hosts exploit the disrupted social and environmental conditions of extreme weather events. This review article examines infectious disease risks associated with extreme weather events; it draws on recent experiences including Hurricane Katrina in 2005 and the 2010 Pakistan mega-floods, and historical examples from previous centuries of epidemics and ‘pestilence’ associated with extreme weather disasters and climatic changes. A fuller understanding of climatic change, the precursors and triggers of extreme weather events and health consequences is needed in order to anticipate and respond to the infectious disease risks associated with human-driven climate change. Post-event risks to human health can be constrained, nonetheless, by reducing background rates of persistent infection, preparatory action such as coordinated disease surveillance and vaccination coverage, and strengthened disaster response. In the face of changing climate and weather conditions, it is critically important to think in ecological terms about the determinants of health, disease and death in human populations. PMID:26168924
Assaad, F.; Gispen, R.; Kleemola, M.; Syrůček, L.; Esteves, K.
In 1963 the World Health Organization established a system for the collection and dissemination of information on viral infections and by 1976, laboratories in 49 countries were participating in this scheme. The present study is in two parts: part 1 is an analysis of almost 60 000 reports on neurological disease associated with viral and Mycoplasma pneumoniae infections reported during the 10-year period 1967-76. This analysis showed a steady increase in the yearly number of reports of viral neurological diseases, which closely followed the general increase in the overall reporting of virus diseases. Likewise, the seasonal pattern was similar to that seen in general for any given virus. Over 75% of the cases were in children. Over half of all viral neurological diseases were associated with enteroviruses, while the myxoviruses accounted for almost 30%. Among the myxoviruses, mumps virus was by far the most frequently reported. The polioviruses were the agents most commonly detected in cases of paralytic disease. The other enteroviruses, mumps virus, and the herpesviruses were the most frequently reported viruses in cases of aseptic meningitis or encephalitis. On the other hand, one-third to over one-half of the reports on the myxoviruses (excluding mumps and measles) related to ill-defined clinical conditions. Part 2 of the study deals in particular with viruses whose role in neurological disease is less well documented. One laboratory reported an outbreak of adenoviral aseptic meningitis in Czechoslovakia, while another described neurological disease associated with M. pneumoniae infection in Finland. Part 2 also includes a detailed appraisal of viral infections diagnosed in the Netherlands during the period 1973-76. The results are very similar to those routinely reported. PMID:6249511
O'Mahony, M. C.; Stanwell-Smith, R. E.; Tillett, H. E.; Harper, D.; Hutchison, J. G. P.; Farrell, I. D.; Hutchinson, D. N.; Lee, J. V.; Dennis, P. J.; Duggal, H. V.; Scully, J. A.; Denne, C.
A large outbreak of Legionnaires' disease was associated with Stafford District General Hospital. A total of 68 confirmed cases was treated in hospital and 22 of these patients died. A further 35 patients, 14 of whom were treated at home, were suspected cases of Legionnaires' disease. All these patients had visited the hospital during April 1985. Epidemiological investigations demonstrated that there had been a high risk of acquiring the disease in the out patient department (OPD), but no risk in other parts of the hospital. The epidemic strain of Legionella pneumophila, serogroup 1, subgroup Pontiac 1a was isolated from the cooling water system of one of the air conditioning plants. This plant served several departments of the hospital including the OPD. The water in the cooling tower and a chiller unit which cooled the air entering the OPD were contaminated with legionellae. Bacteriological and engineering investigations showed how the chiller unit could have been contaminated and how an aerosol containing legionellae could have been generated in the U-trap below the chiller unit. These results, together with the epidemiological evidence, suggest that the chiller unit was most likely to have been the major source of the outbreak. Nearly one third of hospital staff had legionella antibodies. These staff were likely to have worked in areas of the hospital ventilated by the contaminated air conditioning plant, but not necessarily the OPD. There was evidence that a small proportion of these staff had a mild legionellosis and that these `influenza-like' illnesses had been spread over a 5-month period. A possible explanation of this finding is that small amounts of aerosol from cooling tower sources could have entered the air-intake and been distributed throughout the areas of the hospital served by this ventilation system. Legionellae, subsequently found to be of the epidemic strain, had been found in the cooling tower found in November 1984 and thus it is possible
O'Mahony, M C; Stanwell-Smith, R E; Tillett, H E; Harper, D; Hutchison, J G; Farrell, I D; Hutchinson, D N; Lee, J V; Dennis, P J; Duggal, H V
A large outbreak of Legionnaires' disease was associated with Stafford District General Hospital. A total of 68 confirmed cases was treated in hospital and 22 of these patients died. A further 35 patients, 14 of whom were treated at home, were suspected cases of Legionnaires' disease. All these patients had visited the hospital during April 1985. Epidemiological investigations demonstrated that there had been a high risk of acquiring the disease in the out patient department (OPD), but no risk in other parts of the hospital. The epidemic strain of Legionella pneumophila, serogroup 1, subgroup Pontiac 1a was isolated from the cooling water system of one of the air conditioning plants. This plant served several departments of the hospital including the OPD. The water in the cooling tower and a chiller unit which cooled the air entering the OPD were contaminated with legionellae. Bacteriological and engineering investigations showed how the chiller unit could have been contaminated and how an aerosol containing legionellae could have been generated in the U-trap below the chiller unit. These results, together with the epidemiological evidence, suggest that the chiller unit was most likely to have been the major source of the outbreak. Nearly one third of hospital staff had legionella antibodies. These staff were likely to have worked in areas of the hospital ventilated by the contaminated air conditioning plant, but not necessarily the OPD. There was evidence that a small proportion of these staff had a mild legionellosis and that these 'influenza-like' illnesses had been spread over a 5-month period. A possible explanation of this finding is that small amounts of aerosol from cooling tower sources could have entered the air-intake and been distributed throughout the areas of the hospital served by this ventilation system. Legionellae, subsequently found to be of the epidemic strain, had been found in the cooling tower pond in November 1984 and thus it is possible
Deregt, D; Loewen, K G
Bovine viral diarrhea virus continues to produce significant economic losses for the cattle industry and challenges investigators with the complexity of diseases it produces and the mechanisms by which it causes disease. This paper updates and attempts to clarify information regarding the roles of noncytopathic and cytopathic bovine viral diarrhea viruses in persistent infections and mucosal disease. It also covers, in brief, what is known of the new diseases: thrombocytopenia and hemorrhagic disease, and a disease resembling mucosal disease that is apparently caused solely by noncytopathic virus. Although a good understanding of the roles of the 2 biotypes in the production of persistent infections and the precipitation of mucosal disease has been obtained, there are still unanswered questions regarding the origin of cytopathic viruses and the mechanism by which they cause pathological changes in cells. It is apparent, however, that cytopathic bovine viral diarrhea viruses arise by mutation of noncytopathic viruses, and it is known that p80 is the marker protein for cytopathic viruses. The previous distinction between mild bovine viral diarrhea and fatal mucosal disease has been eroded with the emergence of new virulent bovine viral diarrhea viruses. The new diseases pose a threat to the cattle industry and present a new challenge for investigators. Index Veterinarius (1984-1994) and Medline (1985-1994) databases and personal files updated since 1987 from BIOSIS Previews and Biosciences Information Services were used to search the literature. Images Figure 1. PMID:7648541
Chiriac, Anca; Foia, Liliana; Chiriac, Anca; Nanescu, Sonia; Filip, Florina; Solovan, C; Gorduza, E V
Hand, foot and mouth disease (HFMD) is a viral illness usually occurring during the summer months in children younger than 5 years of age. In the North-East area of Romania the incidence is usually low, each dermatologist reporting 1-2 cases or even less per year. The diagnosis is usually based on the characteristic clinical aspect: vesicles and papules on the hands and feet and superficial oral ulcers. HFMD is typically a benign and self-limiting disease that resolves in approximately 7 days; in Asia there have been few reported severe cases that developed neurological complications and even death, while in certain areas of China this disease is a more and more serious public health problem. In the summer of 2012 in North-East Romania numerous cases of disease have been reported, some with atypical clinical manifestations and most of them with mild or moderate forms of disease. The present article is a discussion on one of these cases. The diagnosis was made based on lesions location and clinical appearance. An outbreak of HFMD should be confirmed by virology tests.
Brozik, Susan M; Manginell, Ronald P; Moorman, Matthew W; Xiao, Xiaoyin; Edwards, Thayne L.; Anderson, John Moses; Pfeifer, Kent Bryant; Branch, Darren W.; Wheeler, David Roger; Polsky, Ronen; Lopez, DeAnna M.; Ebel, Gregory D.; Prasad, Abhishek N.; Brozik, James A.; Rudolph, Angela R.; Wong, Lillian P.
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 of 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.
Dato, Virginia; Wagner, Michael M.; Fapohunda, Abi
To learn how outbreaks of infectious disease are detected and to describe the entities and information systems that together function to identify outbreaks in the U.S., the authors drew on multiple sources of information to create a description of existing surveillance systems and how they interact to detect outbreaks. The results of this analysis were summarized in a system diagram. The authors reviewed a sample of recent outbreaks to determine how they were detected, with reference to the system diagram. The de facto U.S. system for detection of outbreaks consists of five components: the clinical health care system, local/state health agencies, federal agencies, academic/professional organizations, and collaborating governmental organizations. Primary data collection occurs at the level of clinical health care systems and local health agencies. The review of a convenience sample of outbreaks showed that all five components of the system participated in aggregating, analyzing, and sharing data. The authors conclude that the current U.S. approach to detection of disease outbreaks is complex and involves many organizations interacting in a loosely coupled manner. State and local health departments and the health care system are major components in the detection of outbreaks. PMID:15313109
Beard, P.M.; Sugar, S.; Bazarragchaa, E.; Gerelmaa, U.; Tserendorj, Sh.; Tuppurainen, E.; Sodnomdarjaa, R.
Mongolia had no reported cases of capripoxvirus disease from 1977 until an outbreak of sheeppox in 2006–2007 and then goatpox in 2008. The two outbreaks occurred in geographically distant areas of Mongolia and, most strikingly, were highly species-specific. The 2006–2007 sheeppox outbreak affected no goats and the 2008 goatpox outbreak affected no sheep despite communal herding. The diseases were diagnosed using the polymerase chain reaction and virus neutralisation test. The P32 gene of the Mongolian sheeppox and goatpox viruses from the recent outbreaks were sequenced and compared with an archived 1967 strain of Goatpox virus from Mongolia. The P32 gene of the 2006–2007 Mongolian Sheeppox virus strain was identical to previously published sheeppox strains. The P32 gene of the 2008 Mongolian Goatpox virus strain was identical to the gene from virus isolated from recent goatpox outbreaks in China and Vietnam. The archived Mongolian Goatpox virus strain was unique. PMID:19939588
Bodewes, R; Egberink, H F
In this review, recent developments in the field of viral diseases of the dog and the cat are discussed. In the dog, infection with the coronavirus type 2 is associated with respiratory signs, while infection of a highly pathogenic strain of the coronavirus type 1 has been identified as the cause of mortality in puppies. A new strain of the canine parvovirus is identified, from which the pathogenicity is not yet completely clarified. Infection with West Nile virus is associated with progressive neurological disease and subclinical infections in dogs. Infection with equine influenza A (H3N8) or a highly related influenza virus can cause severe respiratory disease and mortality in greyhounds and other dogs. Infection with avian influenza A (H5N1) can cause disease and mortality in cats and is mostly subclinical in dogs. A number of outbreaks of highly virulent strains of the calicivirus in cats have been described.
Despite advancements in water management and sanitation, waterborne disease outbreaks continue to occur in the United States. CDC collects data on waterborne disease outbreaks submitted from all states and territories* through the Waterborne Disease and Outbreak Surveillance Syst...
Parkes-Ratanshi, Rosalind; Elbireer, Ali; Mbambu, Betty; Mayanja, Faridah; Coutinho, Alex; Merry, Concepta
Introduction There have been 3 outbreaks of viral hemorrhagic fever (VHF) in Uganda in the last 2 years. VHF often starts with non-specific symptoms prior to the onset of haemorrhagic signs. HIV clinics in VHF outbreak countries such as Uganda see large numbers of patients with HIV 1/2 infection presenting with non-specific symptoms every day. Whilst there are good screening tools for general health care facilities expecting VHF suspects, we were unable to find tools for use in HIV or other non-acute clinics. Methods We designed tools to help with communication to staff, infection control and screening of HIV patients with non-specific symptoms in a large HIV clinic during the outbreaks in Uganda. We describe our experiences in using these tools in 2 Ebola Virus Disease outbreaks in Uganda. Results During the Ebola Virus Disease (EVD) outbreaks, enhanced infection control and communication procedures were implemented within 24 hours of the WHO/Ministry of Health announcement of the outbreaks. During course of these outbreaks the clinic saw 12,544 patients with HIV 1/2 infection, of whom 3,713 attended without an appointment, suggesting new symptoms. Of these 4 were considered at risk of EVD and seen with full infection procedures; 3 were sent home after further investigation. One patient was referred to the National Referral Hospital VHF unit, but discharged on the same day. One additional VHF suspect was identified outside of a VHF outbreak; he was transferred to the National Referral Hospital and placed in isolation within 2 hours of arriving at the HIV clinic. Discussion Use of simple screening tools can be helpful in managing large numbers of symptomatic patients attending for routine and non-routine medical care (including HIV care) within a country experiencing a VHF outbreak, and can raise medical staff awareness of VHF outside of the epidemics. PMID:25007269
Heron, S. F.; Willis, B. L.; Skirving, W. J.; Page, C. A.; Eakin, C. M.; Miller, I. R.; Christensen, T. R.; Gledhill, D. K.; Liu, G.; Morgan, J. A.; Parker, B. A.; Strong, A. E.
Several environmental parameters have been linked to outbreaks of coral disease. Here we describe the influence of remotely-sensed summer and winter temperatures, as well as local observations of coral cover, to predict the risk of White Syndrome disease outbreaks on the Great Barrier Reef, Australia. Coral disease is an emerging risk to coral reef ecosystems that is likely to escalate with ocean warming due to climate change. The aim of this work is to provide reef managers with an expert system for predicting disease risk on coral reefs as far as six months in advance of summer outbreaks.
Isshik, T; Nishizawa, T; Kobayashi, T; Nagano, T; Miyazaki, T
A rhabdoviral disease occurred in farmed populations of market sized Japanese flounder (hirame) Paralichthys olivaceus in the Seto Inland Sea of Japan in 1996. The causative agent was identified as viral hemorrhagic septicemia virus (VHSV) based on morphological, immunological, and genetic analyses. Diseased fish that were artificially injected with a representative virus isolate showed the same pathological signs and high mortality as observed in the natural outbreak. This is the first report of an outbreak of VHSV infection in cultured fish in Japan. Clinical signs of diseased fish included dark body coloration, an expanded abdomen due to ascites, congested liver, splenomegaly, and a swollen kidney. Myocardial necrosis was most prominent and accompanied by inflammatory reactions. Necrotic lesions also occurred in the liver, spleen and hematopoietic tissue, and were accompanied by circulatory disturbances due to cardiac failure. Hemorrhagic lesions did not always appear in the lateral musculature. Transmission electron microscopy revealed many rhabdovirus particles and associated inclusion bodies containing nucleocapsids in the necrotized myocardium. The histopathological findings indicated that the necrotizing myocarditis could be considered a pathognomonic sign of VHSV infection in Japanese flounder.
Hossain, Liaquat; Hassan, Muhammad Rabiul; Wigand, Rolf T
Foodborne disease outbreaks are increasingly being seen as a greater concern by public health authorities. It has also become a global research agenda to identify improved pathways to coordinating outbreak detection. Furthermore, a significant need exists for timely coordination of the detection of potential foodborne disease outbreaks to reduce the number of infected individuals and the overall impact on public health security. This study aimed to offer an effective approach for coordinating foodborne disease outbreaks. First, we identify current coordination processes, complexities, and challenges. We then explore social media surveillance strategies, usage, and the power of these strategies to influence decision-making. Finally, based on informal (social media) and formal (organizational) surveillance approaches, we propose a hybrid information network model for improving the coordination of outbreak detection.
Wong, Emmy M. Y.; Cheng, May M. H.; Lo, S.K.
The outbreak of the Influenza A (H1N1) virus has led to numerous precautionary school closures in several countries. No research is available on the school teachers' perceptions as a health protective resource in controlling communicable disease outbreaks. The purposes of this study were to examine the risk perception, the perceived understanding…
Nieuwenhuijse, David F.; Koopmans, Marion P. G.
A plethora of viruses can be transmitted by the food- and waterborne route. However, their recognition is challenging because of the variety of viruses, heterogeneity of symptoms, the lack of awareness of clinicians, and limited surveillance efforts. Classical food- and waterborne viral disease outbreaks are mainly caused by caliciviruses, but the source of the virus is often not known and the foodborne mode of transmission is difficult to discriminate from human-to-human transmission. Atypical food- and waterborne viral disease can be caused by viruses such as hepatitis A and hepatitis E. In addition, a source of novel emerging viruses with a potential to spread via the food- and waterborne route is the repeated interaction of humans with wildlife. Wildlife-to-human adaptation may give rise to self- limiting outbreaks in some cases, but when fully adjusted to the human host can be devastating. Metagenomic sequencing has been investigated as a promising solution for surveillance purposes as it detects all viruses in a single protocol, delivers additional genomic information for outbreak tracing, and detects novel unknown viruses. Nevertheless, several issues must be addressed to apply metagenomic sequencing in surveillance. First, sample preparation is difficult since the genomic material of viruses is generally overshadowed by host- and bacterial genomes. Second, several data analysis issues hamper the efficient, robust, and automated processing of metagenomic data. Third, interpretation of metagenomic data is hard, because of the lack of general knowledge of the virome in the food chain and the environment. Further developments in virus-specific nucleic acid extraction methods, bioinformatic data processing applications, and unifying data visualization tools are needed to gain insightful surveillance knowledge from suspect food samples. PMID:28261185
Simmons, K; Hullinger, P
Foot and Mouth disease (FMD) is a highly infectious and contagious viral disease affecting cloven-hoofed livestock that was last detected in the United States (US) in 1929. The prevalence of FMD in other countries, as well as the current potential for this virus to be used as a form of agroterrorism, has made preparations for a potential FMD outbreak a national priority. To assist in the evaluation of national preparedness, all 50 states were surveyed via e-mail, telephone and web search to obtain emergency response plans for FMD or for foreign animal diseases in general. Information from 33 states was obtained and analyzed for estimates of personnel resources needed to respond to an outbreak. These estimates were consolidated and enhanced to create a tool that could be used by individual states to better understand the personnel that would be needed to complete various tasks over time during an outbreak response. The estimates were then coupled, post-processing, to the output from FMD outbreaks simulated in California using the Multiscale Epidemiological/Economic Simulation and Analysis (MESA) model at Lawrence Livermore National Laboratory to estimate the personnel resource demands, by task, over the course of an outbreak response.
Grein, T. W.; Kamara, K. B.; Rodier, G.; Plant, A. J.; Bovier, P.; Ryan, M. J.; Ohyama, T.; Heymann, D. L.
Emerging infectious diseases and the growth of information technology have produced new demands and possibilities for disease surveillance and response. Increasing numbers of outbreak reports must be assessed rapidly so that control efforts can be initiated and unsubstantiated reports can be identified to protect countries from unnecessary economic damage. The World Health Organization has set up a process for timely outbreak verification to convert large amounts of data into accurate information for suitable action. We describe the context and processes of outbreak verification and information dissemination. PMID:10756142
Yang, Kun; LeJeune, Jeffrey; Alsdorf, Doug; Lu, Bo; Shum, C. K.; Liang, Song
Background Water plays an important role in the transmission of many infectious diseases, which pose a great burden on global public health. However, the global distribution of these water-associated infectious diseases and underlying factors remain largely unexplored. Methods and Findings Based on the Global Infectious Disease and Epidemiology Network (GIDEON), a global database including water-associated pathogens and diseases was developed. In this study, reported outbreak events associated with corresponding water-associated infectious diseases from 1991 to 2008 were extracted from the database. The location of each reported outbreak event was identified and geocoded into a GIS database. Also collected in the GIS database included geo-referenced socio-environmental information including population density (2000), annual accumulated temperature, surface water area, and average annual precipitation. Poisson models with Bayesian inference were developed to explore the association between these socio-environmental factors and distribution of the reported outbreak events. Based on model predictions a global relative risk map was generated. A total of 1,428 reported outbreak events were retrieved from the database. The analysis suggested that outbreaks of water-associated diseases are significantly correlated with socio-environmental factors. Population density is a significant risk factor for all categories of reported outbreaks of water-associated diseases; water-related diseases (e.g., vector-borne diseases) are associated with accumulated temperature; water-washed diseases (e.g., conjunctivitis) are inversely related to surface water area; both water-borne and water-related diseases are inversely related to average annual rainfall. Based on the model predictions, “hotspots” of risks for all categories of water-associated diseases were explored. Conclusions At the global scale, water-associated infectious diseases are significantly correlated with socio
Parashar, U. D.; Dow, L.; Fankhauser, R. L.; Humphrey, C. D.; Miller, J.; Ando, T.; Williams, K. S.; Eddy, C. R.; Noel, J. S.; Ingram, T.; Bresee, J. S.; Monroe, S. S.; Glass, R. I.
Although food handlers are often implicated as the source of infection in outbreaks of food-borne viral gastroenteritis, little is known about the timing of infectivity in relation to illness. We investigated a gastroenteritis outbreak among employees of a manufacturing company and found an association (RR = 14.1, 95% CI = 2.0-97.3) between disease and eating sandwiches prepared by 6 food handlers, 1 of whom reported gastroenteritis which had subsided 4 days earlier. Norwalk-like viruses were detected by electron microscopy or reverse transcriptase-polymerase chain reaction (RT-PCR) in stool specimens from several company employees, the sick food handler whose specimen was obtained 10 days after resolution of illness, and an asymptomatic food handler. All RT-PCR product sequences were identical, suggesting a common source of infection. These data support observations from recent volunteer studies that current recommendations to exclude food handlers from work for 48-72 h after recovery from illness may not always prevent transmission of Norwalk-like viruses because virus can be shed up to 10 days after illness or while exhibiting no symptoms. PMID:10030711
Taylor, L F; Van Donkersgoed, J; Radostits, O M; Booker, C W; Dubovi, E J; van den Hurk, J V; Janzen, E D
This study describes the epidemiological investigation of an outbreak of mucosal disease that occurred on a ranch in southwestern Saskatchewan. Over a six-month period during the fall and winter of 1991-1992, in a herd of 515 beef cattle and 96 bison, 20 yearling cattle from a group of 105 housed in one feedlot pen died from mucosal disease. A further eight yearlings were slaughtered for salvage because they were at risk of dying from mucosal disease. Mucosal disease mortalities were the first observed evidence of fetal infections with bovine viral diarrhea virus in this herd. Animals that died from mucosal disease exhibited signs of ill thrift prior to death. Deaths from mucosal disease were confined to the progeny of one herd of beef cows. Following an outbreak of fetal infection with bovine viral diarrhea virus during 1989-1990, at least 28 (22%) of the 128 calves born from this herd of cows in the spring of 1990 were persistently infected with bovine viral diarrhea virus. However, only one calf born from this herd in 1991, and five calves born from all herds in 1992 were persistently infected. Of the five persistently infected calves born in 1992, three were born to persistently infected replacement heifers born in 1990. These heifers calved without assistance in 1992, but only one of their calves survived past three days of age, and it was persistently infected. In January 1992, 82% of the total herd had reciprocal antibody titers to bovine viral diarrhea virus of > or = 1024 which suggested a high level of herd immunity to bovine viral diarrhea virus.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8076288
Jones, Timothy F; Rosenberg, Lauren; Kubota, Kristy; Ingram, L Amanda
Over 1,100 foodborne disease outbreaks cause over 23,000 illnesses in the United States annually, but the rates of outbreaks reported and successful investigation vary dramatically among states. We used data from the Centers for Disease Control and Prevention's outbreak reporting database, Association of Public Health Laboratories' PulseNet laboratory subtyping network survey and Salmonella laboratory survey, national public health surveillance data, and national surveys to examine potential causes of this variability. The mean rate of reporting of Salmonella outbreaks was higher in states requiring submission of all isolates to the state public health laboratory, compared to those that do not (5.9 vs. 4.1 per 10 million population, p=0.0062). Rates of overall outbreak reporting or successful identification of an etiology or food vehicle did not correlate at the state level with population, rates of sporadic disease reporting, health department organizational structure, or self-reported laboratory or epidemiologic capacity. Foodborne disease outbreak surveillance systems are complex, and improving them will require a multi-faceted approach to identifying and overcoming barriers.
Coughlin, Steven S
Anxiety and mood disorders are common in the general population in countries around the world. This article provides a review of the recent literature on anxiety and depressive disorders with a focus on linkages with several important viral diseases. Although the majority of studies have been conducted in developed countries such as the United States and Great Britain, some studies have been carried out in less developed nations where only a small percentage of persons with mental illness receive treatment for their condition. The studies summarized in this review indicate that there are important linkages between anxiety and depression and viral diseases such as influenza A (H1N1) and other influenza viruses, varicella-zoster virus, herpes simplex virus, human immunodeficiency virus/acquired immune deficiency syndrome, and hepatitis C. Additional studies are needed to further clarify the mechanisms for interactions between mental health and communicable diseases, in order to assist patients and further prevention and control efforts.
Wallender, Erika K; Ailes, Elizabeth C; Yoder, Jonathan S; Roberts, Virginia A; Brunkard, Joan M
Disease outbreaks associated with drinking water drawn from untreated groundwater sources represent a substantial proportion (30.3%) of the 818 drinking water outbreaks reported to CDC's Waterborne Disease and Outbreak Surveillance System (WBDOSS) during 1971 to 2008. The objectives of this study were to identify underlying contributing factors, suggest improvements for data collection during outbreaks, and inform outbreak prevention efforts. Two researchers independently reviewed all qualifying outbreak reports (1971 to 2008), assigned contributing factors and abstracted additional information (e.g., cases, etiology, and water system attributes). The 248 outbreaks resulted in at least 23,478 cases of illness, 390 hospitalizations, and 13 deaths. The majority of outbreaks had an unidentified etiology (n = 135, 54.4%). When identified, the primary etiologies were hepatitis A virus (n = 21, 8.5%), Shigella spp. (n = 20, 8.1%), and Giardia intestinalis (n = 14, 5.7%). Among the 172 (69.4%) outbreaks with contributing factor data available, the leading contamination sources included human sewage (n = 57, 33.1%), animal contamination (n = 16, 9.3%), and contamination entering via the distribution system (n = 12, 7.0%). Groundwater contamination was most often facilitated by improper design, maintenance or location of the water source or nearby waste water disposal system (i.e., septic tank; n = 116, 67.4%). Other contributing factors included rapid pathogen transport through hydrogeologic formations (e.g., karst limestone; n = 45, 26.2%) and preceding heavy rainfall or flooding (n = 36, 20.9%). This analysis underscores the importance of identifying untreated groundwater system vulnerabilities through frequent inspection and routine maintenance, as recommended by protective regulations such as Environmental Protection Agency's (EPA's) Groundwater Rule, and the need for special consideration of the local hydrogeology.
Imanishi, Maho; Manikonda, Karunya; Murthy, Bhavini P; Gould, L Hannah
The number of foodborne disease outbreaks reported in the United States declined substantially in 2009, when the surveillance system transitioned from reporting only foodborne disease outbreaks to reporting all enteric disease outbreaks. A 2013 survey found that some outbreaks that would have been previously reported as foodborne are now reported as having other transmission modes.
Singh, Kanwardeep; Sidhu, Shailpreet K; Devi, Pushpa; Kaur, Maninder; Singh, Nachhatarjit
Introduction There is a paucity of published data on epidemiology of the viral infections in Punjab, India. The Viral Research and Diagnostic Laboratory (VRDL) located at Government Medical College (GMC), Amritsar conducts the initial diagnosis of common viruses circulating in the region. Aim To report the seroprevalence of various viral diseases in Amritsar and neighboring districts of Punjab along with the demographic and geographical data of the patients. Materials and Methods Whole blood sera samples from a total of 5781 patients suspected of various viral diseases (chikungunya, dengue, hepatitis A, hepatitis B, hepatitis C, hepatitis E, herpes simplex-1 or herpes simplex-2) were received at VRDL, GMC, Amritsar from January 2015 to April 2016 and a cross sectional study was conducted. The diagnosis was based on serological assays. Results Out of total 5781 suspected cases, 1790 were diagnosed with antibodies for atleast one of the tested viral diseases. Dengue virus was the highest occurring viral disease (56.77%). Male patients infected with viruses outnumbered female cases, except for hepatitis E and herpes simplex-1. The 21-40 years age group appeared to be the most susceptible age group for nearly all studied viral infections. Among the total nine reported outbreak investigations, largest encompassed 1335 dengue cases from Amritsar district. Conclusion VRDL established in GMC, Amritsar has become instrumental in detection of emerging and re-emerging viral diseases including outbreak investigation of communicable diseases. Timely action with the help of adequate information and capacity to diagnose the viruses might help in saving numerous lives. PMID:28208856
Verma, S; Verma, L K; Gupta, V K; Katoch, V C; Dogra, V; Pal, B; Sharma, M
Both sheep and goat pox are contagious viral diseases and affect small ruminants and are caused by sheep pox virus and goat pox virus respectively that belong to genus Capripoxvirus of Poxviridae family. Huge economic losses emanating from the disease outbreaks are the results of the wool and hide damage, subsequent production losses and also the morbidities and mortalities associated with the disease. This communication highlights clinico-epidemiological observations from the two sheep pox and one goat pox outbreaks. Grossly, multisystemic nodular lesions, mucopurulent nasal discharges and respiratory symptoms were observed in the affected animals. The morbidity, mortality and case fatality rates were 5.18%, 2.45% and 32.37%, respectively. Histopathological, haematological, molecular and serological techniques and also isolation of virus in embryonated chicken eggs were used for the diagnosis of the diseases. The spatial distribution of the disease signifies the role of common pasturelands used for grazing the animals while temporally all three outbreaks occurred in winters and were probably associated with cold stress and fodder scarcity. This is the first recorded report of Capripoxvirus infection in recent times and it highlights the disease as one of the emerging diseases in the northern state of Himachal Pradesh in India.
Newcomer, Benjamin W; Givens, M Daniel
The pestiviruses, bovine viral diarrhea virus (BVDV), classical swine fever (CSFV) and border disease virus, are important livestock pathogens in many countries, but current vaccines do not completely prevent the spread of infection. Control of pestiviral diseases is especially difficult due to the constant viremia and viral shedding of persistently infected (PI) animals, which must be identified and eliminated to prevent disease transmission. Existing vaccines are limited by the delay between vaccination and the onset of protection, the difficulty of differentiating serologically between vaccinated and naturally infected animals and the need for broad vaccine cross-protection against diverse virus strains. Antiviral therapy could potentially supplement vaccination by providing immediate protection in the case of an outbreak. Numerous compounds with in vitro antiviral activity against BVDV have been identified through its role as a surrogate for hepatitis C virus. Fewer drugs active against CSFV have been identified, but many compounds that are effective against BVDV will likely inhibit CSFV, given their similar genomic sequences. While in vitro research has been promising, the paucity of efficacy studies in animals has hindered the commercial development of effective antiviral drugs against the pestiviruses. In this article, we summarize the clinical syndromes and routes of transmission of BVD, CSF and border disease, discuss currently approved vaccines, review efforts to develop antiviral therapies for use in outbreak control and suggest promising directions for future research.
Nardis, C; Mosca, L; Mastromarino, P
Healthy vaginal microbiota is an important biological barrier to pathogenic microorganisms. When this predominantly Lactobacillus community is disrupted, decreased in abundance and replaced by different anaerobes, bacterial vaginosis (BV) may occur. BV is associated with prevalence and incidence of several sexually transmitted infections. This review provides background on BV, discusses the epidemiologic data to support a role of altered vaginal microbiota for acquisition of sexually transmitted diseases and analyzes mechanisms by which lactobacilli could counteract sexually transmitted viral infections.
Arcangioli, Marie-Anne; Duet, Arnaud; Meyer, Gilles; Dernburg, Ann; Bézille, Pierre; Poumarat, François; Le Grand, Dominique
To assess the prevalence and relative importance of Mycoplasma bovis among the pathological agents implicated in bovine respiratory disease (BRD), we surveyed 135 veal calves from nine feedlots in eastern France during naturally occurring outbreaks of respiratory disease. Occurrence of respiratory pathogens, M. bovis, bovine viral diarrhoea (BVD) virus, bovine respiratory syncytial (BRS) virus and parainfluenza-3 (PI3) virus was investigated by seroconversion and isolation of bacteria and viruses from broncho-alveolar fluids. M. bovis and pathogenic respiratory bacteria were isolated in eight of the nine feedlots, and from 106 and 32, respectively, of the 135 tested animals. Seroconversion to PI3 virus occurred in four lots. BVD and BRS viruses were detected in eight and one lot, respectively. M. bovis was the most frequently isolated aetiologic agent in these BRD outbreaks, spreading early and widely throughout the affected units (60-100% rate of isolation and seroconversion). These results stress the importance of M. bovis in the BRD complex.
Aarestrup, Frank M; Koopmans, Marion G
Rapid global sharing and comparison of epidemiological and genomic data on infectious diseases would enable more rapid and efficient global outbreak control and tracking of diseases. Several barriers for global sharing exist but, in our opinion, the presumed magnitude of the problems appears larger than they are, and solutions can be found.
Weber, M N; Mósena, A C S; Simões, S V D; Almeida, L L; Pessoa, C R M; Budaszewski, R F; Silva, T R; Ridpath, J F; Riet-Correa, F; Driemeier, D; Canal, C W
The genus Pestivirus of the family Flaviviridae consists of four recognized species: Bovine viral diarrhoea virus 1 (BVDV-1), Bovine viral diarrhoea virus 2 (BVDV-2), Classical swine fever virus (CSFV) and Border disease virus (BDV). Recently, atypical pestiviruses ('HoBi'-like pestiviruses) were identified in batches of contaminated foetal calf serum and in naturally infected cattle with and without clinical symptoms. Here, we describe the first report of a mucosal disease-like clinical presentation (MD) associated with a 'HoBi'-like pestivirus occurring in a cattle herd. The outbreak was investigated using immunohistochemistry, antibody detection, viral isolation and RT-PCR. The sequence and phylogenetic analysis of 5'NCR, N(pro) and E2 regions of the RT-PCR positive samples showed that four different 'HoBi'-like strains were circulating in the herd. The main clinical signs and lesions were observed in the respiratory and digestive systems, but skin lesions and corneal opacity were also observed. MD characteristic lesions and a pestivirus with cytopathic biotype were detected in one calf. The present study is the first report of a MD like presentation associated with natural infection with 'HoBi'-like pestivirus. This report describes the clinical signs and provides a pathologic framework of an outbreak associated with at least two different 'HoBi'-like strains. Based on these observations, it appears that these atypical pestiviruses are most likely underdiagnosed in Brazilian cattle.
Parthiban, Aravindh Babu R; Mahapatra, Mana; Gubbins, Simon; Parida, Satya
The role of foot-and-mouth disease virus (FMDV) carrier cattle in causing new outbreaks is still a matter of debate and it is important to find out these carrier animals by post-outbreak serosurveillance to declare freedom from FMDV infection. In this study we explore the differences in viral shedding between carrier and non-carrier animals, quantify the transmission rate of FMDV infection from carriers to susceptible animals and identify potential viral determinants of viral persistence. We collected nasal and saliva samples from 32 vaccinated and 7 unvaccinated FMDV carrier cattle and 48 vaccinated and 13 unvaccinated non-carrier cattle (total n=100) during the acute phase of infection (up to 28 days post-challenge) and then from limited number of animals up to a maximum 168 days post-challenge. We demonstrate that unvaccinated cattle excrete significantly higher levels of virus for longer periods compared with vaccinated cattle and this is independent of whether or not they subsequently become carriers. By introducing naïve cattle in to the FMDV carrier population we show the risk of new outbreaks is clearly very low in controlled conditions, although there could still be a potential threat of these carrier animals causing new outbreaks in the field situation. Finally, we compared the complete genome sequences of viruses from carrier cattle with the challenge virus and found no evidence for viral determinants of the carrier state.
Background Investigations were conducted by the authors to explore an outbreak of viral hemorrhagic fever (VHF) reported in 2010 from Al-Mukalla city, the capital of Hadramout in Yemen. Methods From 15–17 June 2010, the outbreak investigation period, specimens were obtained within 7 days after onset of illness of 18 acutely ill patients hospitalized with VHF and 15 household asymptomatic contacts of 6 acute cases. Additionally, 189 stored sera taken from acutely ill patients with suspected VHF hospitalized in the preceding 12 months were obtained from the Ministry of Health of Yemen. Thus, a total of 222 human specimens were collected; 207 specimens from acute cases and 15 specimens from contacts. All samples were tested with RT-PCR for dengue (DENV), Alkhumra (ALKV), Rift Valley Fever (RVFV), Yellow Fever (YFV), and Chikungunya (CHIKV) viruses. Samples were also tested for DENV IgM, IgG, and NS1-antigen. Medical records of patients were reviewed and demographic, clinical, and laboratory data was collected. Results Of 207 patients tested, 181 (87.4%) patients were confirmed to have acute dengue with positive dengue NS1-antigen (97 patients, 46.9%) and/or IgM (163 patients, 78.7%). Of the 181 patients with confirmed dengue, 100 (55.2%) patients were IgG-positive. DENV RNA was detected in 2 (1%) patients with acute symptoms; both samples were molecularly typed as DENV type 3. No other VHF viruses were detected. For the 15 contacts tested, RT-PCR tests for the five viruses were negative, one contact was dengue IgM positive, and another one was dengue IgG positive. Of the 181 confirmed dengue patients, 120 (66.3%) patients were males and the median age was 24 years. The most common manifestations included fever (100%), headache (94.5%), backache (93.4%), malaise (88.4%), arthralgia (85.1%), myalgia (82.3%), bone pain (77.9%), and leukopenia (76.2%). Two (1.1%) patients died. Conclusions DENV-3 was confirmed to be the cause of an outbreak of VHF in Al
Brentjens, Mathijs H; Yeung-Yue, Kimberly A; Lee, Patricia C; Tyring, Stephen K
Vaccines against infectious diseases have been available since the 1800s, when an immunization strategy against smallpox developed by Jenner gained wide acceptance. Until recently, the only vaccination strategies available involved the use of protein-based, whole killed, and attenuated live virus vaccines. These strategies have led to the development of effective vaccines against a variety of diseases with primary or prominent cutaneous manifestations. Effective and safe vaccines now used worldwide include those directed against measles and rubella (now commonly used together with a mumps vaccine as the trivalent MMR), chickenpox, and hepatitis B. The eradication of naturally occurring smallpox remains one of the greatest successes in the history of modern medicine, but stockpiles of live smallpox exist in the United States and Russia. Renewed interest in the smallpox vaccine reflects concerns about a possible bioterrorist threat using this virus. Yellow fever is a hemorrhagic virus endemic to tropical areas of South America and Africa. An effective vaccine for this virus has existed since 1937, and it is used widely in endemic areas of South America, and to a lesser extent in Africa. This vaccine is recommended once every 10 years for people who are traveling to endemic areas. Advances in immunology have led to a greater understanding of immune system function in viral diseases. Progress in genetics and molecular biology has allowed researchers to design vaccines with novel mechanisms of action (eg, DNA, vector, and VLP vaccines). Vaccines have also been designed to specifically target particular viral components, allowing for stimulation of various arms of the immune system as desired. Ongoing research shows promise in prophylactic and therapeutic vaccination for viral infections with cutaneous manifestations. Further studies are necessary before vaccines for HSV, HPV, and HIV become commercially available.
Que, Jialan; Tsui, Fu-Chiang
Objective Outbreak detection algorithms monitoring only disease-relevant data streams may be prone to false alarms due to baseline shifts. In this paper, we propose a Multinomial-Generalized-Dirichlet (MGD) model to adjust for baseline shifts. Introduction Population surges or large events may cause shift of data collected by biosurveillance systems . For example, the Cherry Blossom Festival brings hundreds of thousands of people to DC every year, which results in simultaneous elevations in multiple data streams (Fig. 1). In this paper, we propose an MGD model to accommodate the needs of dealing with baseline shifts. Methods Existing multivariate algorithms only model disease-relevant data streams (e.g., anti-fever medication sales or patient visits with constitutional syndrome for detection of flu outbreak). On the contrary, we also incorporate a non-disease-relevant data stream as a control factor. We assume that the counts from all data streams follow a Multinomial distribution. Given this distribution, the expected value of the distribution parameter is not subject to change during a baseline shift; however, it has to change in order to model an outbreak. Therefore, this distribution inherently adjusts for the baseline shifts. In addition, we use the generalized Dirichlet (GD) distribution to model the parameter, since GD distribution is one of the conjugate prior of Multinomial . We call this model the Multinomial-Generalized-Dirichlet (MGD) model. Results We applied MGD model in our previous proposed Rank-Based Spatial Clustering (MRSC) algorithm . We simulated both outbreak cases and baseline shift phenomena. The experiment includes two groups of data sets. The first includes the data sets only injected with outbreak cases, and the second includes the ones with both outbreak cases and baseline shifts. We apply MRSC algorithm and a reference method, the Multivariate Bayesian Scan Statistic (MBSS) algorithm (which only analyzes the disease
Banda, Frank; Kasanga, Christopher J; Sallu, Raphael; Sinkala, Yona; Sinkombe, Tingiya W; Mulumba, Misheck; Rweyemamu, Mark M; Wambura, Philemon N
Foot-and-mouth disease (FMD) is an acute, highly contagious viral infection of domestic and wild cloven-hoofed animals. It is known to be endemic in Zambia, with periodic outbreaks occurring in different geographical areas of the country. This study was conducted to investigate the presence of FMD virus (FMDV) in reported FMD-suspected cases in cattle from the Kazungula and Mbala districts of Zambia. Sixty epithelial tissues or oesophageal-pharyngeal (OP) scrapings (probang samples) were collected from Mbala (n = 51) and Kazungula (n = 9) and examined for FMDV. The FMDV viral RNA and serotypes were examined by realtime reverse transcription polymerase chain reaction (qRT-PCR) and antigen Enzyme- linked immunosorbent assay (ELISA), respectively. Twenty-two samples (36.7%) were positive for the FMDV genome by qRT-PCR with Cycle threshold (Ct) values ranging from 13 to 31. The FMDV-positive samples from epithelial tissues showed relatively higher Ct values compared to those obtained from OP scrapings, irrespective of geographical location. Forty percent (40%; n = 4) of epithelial tissues from Mbala were serotyped into SAT 2 serotype by antigen ELISA. Kazungula samples were serotyped into SAT 1. These findings indicated that Mbala and Kazungula districts had FMD outbreaks in 2012 that were ascribed to at least FMDV serotype SAT 2 and SAT 1 field strains. Furthermore, regular interaction between buffalos from the Mosi-o Tunya Park and domestic animals from surrounding areas could contribute to the occurrence of regular FMD outbreaks in Kazungula, whilst the uncontrolled animal movements across borders between Mbala and Nsumbawanga could be responsible for disease outbreaks in Mbala. In-depth molecular biological studies, including sequencing and phylogeny of the viruses, should be conducted to elucidate the complex epidemiology of FMD in Zambia, thereby providing valuable information needed for the rational control strategy of FMD in Zambia and neighbouring countries.
Angelo, K M; Nisler, A L; Hall, A J; Brown, L G; Gould, L H
Although contamination of food can occur at any point from farm to table, restaurant food workers are a common source of foodborne illness. We describe the characteristics of restaurant-associated foodborne disease outbreaks and explore the role of food workers by analysing outbreaks associated with restaurants from 1998 to 2013 reported to the Centers for Disease Control and Prevention's Foodborne Disease Outbreak Surveillance System. We identified 9788 restaurant-associated outbreaks. The median annual number of outbreaks was 620 (interquartile range 618-629). In 3072 outbreaks with a single confirmed aetiology reported, norovirus caused the largest number of outbreaks (1425, 46%). Of outbreaks with a single food reported and a confirmed aetiology, fish (254 outbreaks, 34%) was most commonly implicated, and these outbreaks were commonly caused by scombroid toxin (219 outbreaks, 86% of fish outbreaks). Most outbreaks (79%) occurred at sit-down establishments. The most commonly reported contributing factors were those related to food handling and preparation practices in the restaurant (2955 outbreaks, 61%). Food workers contributed to 2415 (25%) outbreaks. Knowledge of the foods, aetiologies, and contributing factors that result in foodborne disease restaurant outbreaks can help guide efforts to prevent foodborne illness.
Guimarães, Paulo R., Jr.; de Menezes, Márcio Argollo; Baird, Robin W.; Lusseau, David; Guimarães, Paulo; Dos Reis, Sérgio F.
Emerging infectious diseases are among the main threats to conservation of biological diversity. A crucial task facing epidemiologists is to predict the vulnerability of populations of endangered animals to disease outbreaks. In this context, the network structure of social interactions within animal populations may affect disease spreading. However, endangered animal populations are often small and to investigate the dynamics of small networks is a difficult task. Using network theory, we show that the social structure of an endangered population of mammal-eating killer whales is vulnerable to disease outbreaks. This feature was found to be a consequence of the combined effects of the topology and strength of social links among individuals. Our results uncover a serious challenge for conservation of the species and its ecosystem. In addition, this study shows that the network approach can be useful to study dynamical processes in very small networks.
Xiao, Yanni; Tang, Sanyi; Wu, Jianhong
There are many challenges to quantifying and evaluating the media impact on the control of emerging infectious diseases. We modeled such media impacts using a piecewise smooth function depending on both the case number and its rate of change. The proposed model was then converted into a switching system, with the switching surface determined by a functional relationship between susceptible populations and different subgroups of infectives. By parameterizing the proposed model with the 2009 A/H1N1 influenza outbreak data in the Shaanxi province of China, we observed that media impact switched off almost as the epidemic peaked. Our analysis implies that media coverage significantly delayed the epidemic's peak and decreased the severity of the outbreak. Moreover, media impacts are not always effective in lowering the disease transmission during the entire outbreak, but switch on and off in a highly nonlinear fashion with the greatest effect during the early stage of the outbreak. The finding draws the attention to the important role of informing the public about `the rate of change of case numbers' rather than `the absolute number of cases' to alter behavioral changes, through a self-adaptive media impact switching on and off, for better control of disease transmission.
Xiao, Yanni; Tang, Sanyi; Wu, Jianhong
There are many challenges to quantifying and evaluating the media impact on the control of emerging infectious diseases. We modeled such media impacts using a piecewise smooth function depending on both the case number and its rate of change. The proposed model was then converted into a switching system, with the switching surface determined by a functional relationship between susceptible populations and different subgroups of infectives. By parameterizing the proposed model with the 2009 A/H1N1 influenza outbreak data in the Shaanxi province of China, we observed that media impact switched off almost as the epidemic peaked. Our analysis implies that media coverage significantly delayed the epidemic's peak and decreased the severity of the outbreak. Moreover, media impacts are not always effective in lowering the disease transmission during the entire outbreak, but switch on and off in a highly nonlinear fashion with the greatest effect during the early stage of the outbreak. The finding draws the attention to the important role of informing the public about ‘the rate of change of case numbers' rather than ‘the absolute number of cases' to alter behavioral changes, through a self-adaptive media impact switching on and off, for better control of disease transmission. PMID:25592757
Dewey-Mattia, Daniel; Roberts, Virginia A; Vieira, Antonio; Fullerton, Kathleen E
CDC collects data on foodborne and waterborne disease outbreaks reported by all U.S. states and territories through the Foodborne Disease Outbreak Surveillance System (FDOSS) (http://www.cdc.gov/foodsafety/fdoss/surveillance/index.html) and the Waterborne Disease and Outbreak Surveillance System (WBDOSS) http://www.cdc.gov/healthywater/surveillance), respectively. These two systems are the primary source of national data describing the number of reported outbreaks; outbreak-associated illnesses, hospitalizations, and deaths; etiologic agents; water source or implicated foods; settings of exposure; and other factors associated with recognized foodborne and waterborne disease outbreaks in the United States.
Singh, J.; Bhatia, R.; Gandhi, J. C.; Kaswekar, A. P.; Khare, S.; Patel, S. B.; Oza, V. B.; Jain, D. C.; Sokhey, J.
In India, virtually all outbreaks of viral hepatitis are considered to be due to faeco-orally transmitted hepatitis E virus. Recently, a cluster of 15 cases of viral hepatitis B was found in three villages in Gujarat State. The cases were epidemiologically linked to the use of inadequately sterilized needles and syringes by a local unqualified medical practitioner. The outbreak evolved slowly over a period of 3 months and was marked by a high case fatality rate (46.7%), probably because of concurrent infection with hepatitis D virus (HDV) or sexually transmitted infections. But for the many fatalities within 2-3 weeks of the onset of illness, the outbreak would have gone unnoticed. The findings emphasize the importance of inadequately sterilized needles and syringes in the transmission of viral hepatitis B in India, the need to strengthen the routine surveillance system, and to organize an education campaign targeting all health care workers including private practitioners, especially those working in rural areas, as well as the public at large, to take all possible measures to prevent this often fatal infection. PMID:9615501
Louz, Derrick; Bergmans, Hans E; Loos, Birgit P; Hoeben, Rob C
Mathematical modeling can be used for the development and implementation of infection control policy to combat outbreaks and epidemics of communicable viral diseases. Here an outline is provided of basic concepts and approaches used in mathematical modeling and parameterization of disease transmission. The use of mathematical models is illustrated, using the 2001 UK foot-and-mouth disease (FMD) epidemic, the 2003 global severe acute respiratory syndrome (SARS) epidemic, and human influenza pandemics, as examples. This provides insights in the strengths, limitations, and weaknesses of the various models, and demonstrates their potential for supporting policy and decision making.
Dolan, Thomas W; Butler, Mark J; Shields, Jeffrey D
Social behavior confers numerous benefits to animals but also risks, among them an increase in the spread of pathogenic diseases. We examined the trade-off between risk of predation and disease transmission under different scenarios of host spatial structure and disease avoidance behavior using a spatially explicit, individual-based model of the host pathogen interaction between juvenile Caribbean spiny lobster (Panulirus argus) and Panulirus argus Virus 1 (PaV1). Spiny lobsters are normally social but modify their behavior to avoid diseased conspecifics, a potentially effective means of reducing transmission but one rarely observed in the wild. We found that without lobster avoidance of diseased conspecifics, viral outbreaks grew in intensity and duration in simulations until the virus was maintained continuously at unrealistically high levels. However, when we invoked disease avoidance at empirically observed levels, the intensity and duration of outbreaks was reduced and the disease extirpated within five years. Increased lobster (host) spatial aggregation mimicking that which occurs when sponge shelters for lobsters are diminished by harmful algal blooms, did not significantly increase PaV1 transmission or persistence in lobster populations. On the contrary, behavioral aversion of diseased conspecifics effectively reduced viral prevalence, even when shelters were limited, which reduced shelter availability for all lobsters but increased predation, especially of infected lobsters. Therefore, avoidance of diseased conspecifics selects against transmission by contact, promotes alternative modes of transmission, and results in a more resilient host-pathogen system.
Stene, A; Bang Jensen, B; Knutsen, Ø; Olsen, A; Viljugrein, H
Pancreas disease (PD) is a viral disease causing negative impacts on economy of salmon farms and fish welfare. Its transmission route is horizontal, and water transport by ocean currents is an important factor for transmission. In this study, the effect of temperature changes on PD dynamics in the field has been analysed for the first time. To identify the potential time of exposure to the virus causing PD, a hydrodynamic current model was used. A cohort of salmon was assumed to be infected the month it was exposed to virus from other infective cohorts by estimated water contact. The number of months from exposure to outbreak defined the incubation period, which was used in this investigation to explore the relationship between temperature changes and PD dynamics. The time of outbreak was identified by peak in mortality based on monthly records from active sites. Survival analysis demonstrated that cohorts exposed to virus at decreasing sea temperature had a significantly longer incubation period than cohorts infected when the sea temperature was increasing. Hydrodynamic models can provide information on the risk of being exposed to pathogens from neighbouring farms. With the knowledge of temperature-dependent outbreak probability, the farmers can emphasize prophylactic management, avoid stressful operations until the sea temperature is decreasing and consider removal of cohorts at risk, if possible.
Walker, Peter J; Winton, James R
The rise of aquaculture has been one of the most profound changes in global food production of the past 100 years. Driven by population growth, rising demand for seafood and a levelling of production from capture fisheries, the practice of farming aquatic animals has expanded rapidly to become a major global industry. Aquaculture is now integral to the economies of many countries. It has provided employment and been a major driver of socio-economic development in poor rural and coastal communities, particularly in Asia, and has relieved pressure on the sustainability of the natural harvest from our rivers, lakes and oceans. However, the rapid growth of aquaculture has also been the source of anthropogenic change on a massive scale. Aquatic animals have been displaced from their natural environment, cultured in high density, exposed to environmental stress, provided artificial or unnatural feeds, and a prolific global trade has developed in both live aquatic animals and their products. At the same time, over-exploitation of fisheries and anthropogenic stress on aquatic ecosystems has placed pressure on wild fish populations. Not surprisingly, the consequence has been the emergence and spread of an increasing array of new diseases. This review examines the rise and characteristics of aquaculture, the major viral pathogens of fish and shrimp and their impacts, and the particular characteristics of disease emergence in an aquatic, rather than terrestrial, context. It also considers the potential for future disease emergence in aquatic animals as aquaculture continues to expand and faces the challenges presented by climate change.
Winton, James R.; Walker, Peter J.
The rise of aquaculture has been one of the most profound changes in global food production of the past 100 years. Driven by population growth, rising demand for seafood and a levelling of production from capture fisheries, the practice of farming aquatic animals has expanded rapidly to become a major global industry. Aquaculture is now integral to the economies of many countries. It has provided employment and been a major driver of socio-economic development in poor rural and coastal communities, particularly in Asia, and has relieved pressure on the sustainability of the natural harvest from our rivers, lakes and oceans. However, the rapid growth of aquaculture has also been the source of anthropogenic change on a massive scale. Aquatic animals have been displaced from their natural environment, cultured in high density, exposed to environmental stress, provided artificial or unnatural feeds, and a prolific global trade has developed in both live aquatic animals and their products. At the same time, over-exploitation of fisheries and anthropogenic stress on aquatic ecosystems has placed pressure on wild fish populations. Not surprisingly, the consequence has been the emergence and spread of an increasing array of new diseases. This review examines the rise and characteristics of aquaculture, the major viral pathogens of fish and shrimp and their impacts, and the particular characteristics of disease emergence in an aquatic, rather than terrestrial, context. It also considers the potential for future disease emergence in aquatic animals as aquaculture continues to expand and faces the challenges presented by climate change.
Herrington, James E
Mosquitoes can transmit over 100 of the viruses that can cause encephalitis, meningitis, and hemorrhagic disease in humans (Chin 2000; Gubler 1996; Monath 1989). While much is known about the ecology, epidemiology, and clinical manifestations of the arboviral encephalitides (Campbell et al. 2002; Centers for Disease Control and Prevention 1997; Gubler 1998; Hayes 1989; Hubálek and Halouzka 1999), little empirical research exists regarding the U.S. population's knowledge of mosquitoes and arboviral encephalitis, particularly prior to the U.S. outbreak of West Nile virus (WNV) in 1999. A nationally representative 55-item survey instrument was successfully administered to 1,500 adults in the United States and an additional 250 adults in six states in the Northeast (Connecticut, Delaware, New Jersey, New York, Pennsylvania, and Rhode Island) regarding mosquitoes and mosquito-borne viral encephalitis. A summary outcome measure for mosquito bite prevention was created. Analyses revealed that the following were statistically significant predictors of behaviors taken to prevent mosquito bites: being concerned about being bitten by mosquitoes, perceived effectiveness of staying indoors in late afternoon and early evening was protective, perceived effectiveness that mosquito repellent is not harmful to health, owning dogs and/or cats as pets, being married, and being > or = 18-44 years old. Being concerned about being bitten by mosquitoes was the most robust predictor of behavioral action to prevent mosquito bites (OR = 7.3; 95% CI = 4.3, 12.2). Observed misperceptions and inadequate knowledge regarding insect repellents suggest increased promotion of the safety and efficacy of DEET-containing insect repellents is warranted.
Hunt, D. A.; Cartwright, K. A.; Smith, M. C.; Middleton, J.; Bartlett, C. L.; Lee, J. V.; Dennis, P. J.; Harper, D.
Fourteen people living in or near the city of Gloucester fell ill with Legionnaires' disease caused by Legionella pneumophila serogroup (SG) 1 between 27 August and 27 October 1986. Another patient had fallen ill on 30 May. Nine of the 15 were diagnosed retrospectively during a case finding exercise. There were three deaths. Three cases of Pontiac fever were also diagnosed. The source was probably one or more wet cooling towers. Nineteen premises in the city with such towers were identified, and three just outside Gluocester. Samples from 11 of the 22 premises grew Legionella spp.; from nine of these L. pneumophila SG 1 (Pontiac) was isolated. The efficacy of regular addition of biocide in addition to hypochlorite added at the time of disinfection in inhibiting the growth of Legionella spp. was demonstrated. A survey of patients' movements during their likely incubation period showed that there was no single building that all patients had visited, but there were two areas of the city which nearly all had visited or passed through by car. A case-control study demonstrated an association with one of these areas. Cooling towers near both areas may have been sources but the evidence is insufficient to incriminate any single one. The unexpected finding of L. pneumophila SG 1 (Pontiac) in nine towers supports the hypothesis that there may have been multiple sources. Cooling towers may have been contaminated by mains water or by drift from other towers. PMID:1879480
Hunt, D A; Cartwright, K A; Smith, M C; Middleton, J; Bartlett, C L; Lee, J V; Dennis, P J; Harper, D
Fourteen people living in or near the city of Gloucester fell ill with Legionnaires' disease caused by Legionella pneumophila serogroup (SG) 1 between 27 August and 27 October 1986. Another patient had fallen ill on 30 May. Nine of the 15 were diagnosed retrospectively during a case finding exercise. There were three deaths. Three cases of Pontiac fever were also diagnosed. The source was probably one or more wet cooling towers. Nineteen premises in the city with such towers were identified, and three just outside Gluocester. Samples from 11 of the 22 premises grew Legionella spp.; from nine of these L. pneumophila SG 1 (Pontiac) was isolated. The efficacy of regular addition of biocide in addition to hypochlorite added at the time of disinfection in inhibiting the growth of Legionella spp. was demonstrated. A survey of patients' movements during their likely incubation period showed that there was no single building that all patients had visited, but there were two areas of the city which nearly all had visited or passed through by car. A case-control study demonstrated an association with one of these areas. Cooling towers near both areas may have been sources but the evidence is insufficient to incriminate any single one. The unexpected finding of L. pneumophila SG 1 (Pontiac) in nine towers supports the hypothesis that there may have been multiple sources. Cooling towers may have been contaminated by mains water or by drift from other towers.
Timbury, M. C.; Donaldson, J. R.; McCartney, A. C.; Fallon, R. J.; Sleigh, J. D.; Lyon, D.; Orange, G. V.; Baird, D. R.; Winter, J.; Wilson, T. S.
The bacteriological investigation of an outbreak of Legionnaires' disease in Glasgow Royal Infirmary affecting 16 patients is described. Most of the patients had been treated in high-dependency areas on two floors of the hospital supplied by the same two air-conditioned ventilation systems. The source of infection was traced to contamination of a cooling tower from which a plume of spray discharged into the intake vents of the two ventilation systems. Rubber grommets within the cooling tower probably provided a nidus of infection there. The control and management of the outbreak are discussed: a policy of frankness about the course and progress of the investigations was adopted and helped to allay anxiety on the part of both staff and media. PMID:3540109
Liao, Yilan; Xu, Bing; Wang, Jinfeng; Liu, Xiaochi
Over the past few years, emergent threats posed by infectious diseases and bioterrorism have become public health concerns that have increased the need for prompt disease outbreak warnings. In most of the existing disease surveillance systems, disease outbreak risk is assessed by the detection of disease outbreaks. However, this is a retrospective approach that impacts the timeliness of the warning. Some disease surveillance systems can predict the probabilities of infectious disease outbreaks in advance by determining the relationship between a disease outbreak and the risk factors. However, this process depends on the availability of risk factor data. In this article, we propose a Bayesian belief network (BBN) method to assess disease outbreak risks at different spatial scales based on cases or virus detection rates. Our experimental results show that this method is more accurate than traditional methods and can make uncertainty estimates, even when some data are unavailable. PMID:28067258
Walker, Peter J.; Winton, James R.
The rise of aquaculture has been one of the most profound changes in global food production of the past 100 years. Driven by population growth, rising demand for seafood and a levelling of production from capture fisheries, the practice of farming aquatic animals has expanded rapidly to become a major global industry. Aquaculture is now integral to the economies of many countries. It has provided employment and been a major driver of socio-economic development in poor rural and coastal communities, particularly in Asia, and has relieved pressure on the sustainability of the natural harvest from our rivers, lakes and oceans. However, the rapid growth of aquaculture has also been the source of anthropogenic change on a massive scale. Aquatic animals have been displaced from their natural environment, cultured in high density, exposed to environmental stress, provided artificial or unnatural feeds, and a prolific global trade has developed in both live aquatic animals and their products. At the same time, over-exploitation of fisheries and anthropogenic stress on aquatic ecosystems has placed pressure on wild fish populations. Not surprisingly, the consequence has been the emergence and spread of an increasing array of new diseases. This review examines the rise and characteristics of aquaculture, the major viral pathogens of fish and shrimp and their impacts, and the particular characteristics of disease emergence in an aquatic, rather than terrestrial, context. It also considers the potential for future disease emergence in aquatic animals as aquaculture continues to expand and faces the challenges presented by climate change. PMID:20409453
Spelman, Lucy H; Gilardi, Kirsten V K; Lukasik-Braum, Magdalena; Kinani, Jean-Felix; Nyirakaragire, Elisabeth; Lowenstine, Linda J; Cranfield, Michael R
Between 1990 and 2010, 18 outbreaks of respiratory disease occurred in Rwanda's wild human-habituated mountain gorillas (Gorilla beringei beringei). An outbreak was defined as clinically observable respiratory illness involving at least one third of all the gorillas in a family group (> 30% morbidity) over the course of at least 7 days. Outbreaks lasted 2 wk to 4 mo and affected up to five different gorilla family groups, either concurrently or sequentially. An outbreak was considered over if no further clinical illness was observed in the same or another group for at least 1 mo. Clinical signs varied from nasal discharge, sneezing, and mild intermittent coughing (mild), to spasmodic coughing, lethargy, and partial anorexia (moderate), to dyspnea, tachypnea, respiratory distress, weakness, complete anorexia, and occasionally death (severe). Nearly every mountain gorilla group habituated for tourism or research in Rwanda experienced at least one outbreak, and they may be increasing in frequency. In the first 15 yr of the review period 1990-2005, there were nine outbreaks involving 16 gorilla groups; in the last 5 yr of the review period, 2006-2010, there were nine outbreaks involving 11 groups. Although most gorillas recovered without treatment, 41 veterinary procedures were required to medically manage 35 severely ill individuals. Given the rise of mountain gorilla ecotourism in Rwanda, the possibility that respiratory disease results from contact with infected humans is of great concern, and both the etiology and epidemiology of this problem are active areas of research. The observed clinical signs, response to antimicrobial therapy among the sickest individuals, and postmortem findings are most consistent with viral upper respiratory tract infections complicated in some cases by secondary bacterial infections. The current gorilla visitation rules have been designed to minimize the risk of disease transmission between humans and wild human-habituated great apes.
Ypma, Rolf J F; van Ballegooijen, W Marijn; Wallinga, Jacco
Transmission events are the fundamental building blocks of the dynamics of any infectious disease. Much about the epidemiology of a disease can be learned when these individual transmission events are known or can be estimated. Such estimations are difficult and generally feasible only when detailed epidemiological data are available. The genealogy estimated from genetic sequences of sampled pathogens is another rich source of information on transmission history. Optimal inference of transmission events calls for the combination of genetic data and epidemiological data into one joint analysis. A key difficulty is that the transmission tree, which describes the transmission events between infected hosts, differs from the phylogenetic tree, which describes the ancestral relationships between pathogens sampled from these hosts. The trees differ both in timing of the internal nodes and in topology. These differences become more pronounced when a higher fraction of infected hosts is sampled. We show how the phylogenetic tree of sampled pathogens is related to the transmission tree of an outbreak of an infectious disease, by the within-host dynamics of pathogens. We provide a statistical framework to infer key epidemiological and mutational parameters by simultaneously estimating the phylogenetic tree and the transmission tree. We test the approach using simulations and illustrate its use on an outbreak of foot-and-mouth disease. The approach unifies existing methods in the emerging field of phylodynamics with transmission tree reconstruction methods that are used in infectious disease epidemiology.
Sleeman, Jonathan M.; Ip, Hon S.
The following article provides examples of recently emerged viral diseases of wildlife origin. The examples have been selected to illustrate the drivers of emerging viral diseases, both novel pathogens and previously known diseases, the impacts of these diseases, as well as the role of wildlife both as “villains” or reservoirs as well as “victims” of these viral diseases. The article also discusses potential management strategies for emerging viral diseases in wildlife populations and future science directions in wildlife health to prevent, prepare, respond to, and recover from these disease events. Finally, the concept of One Health and its potential role in developing solutions to these issues of mutual concern is discussed.
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; Branco, Luis M; Khan, Sheik Humarr
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.
Jombart, T; Eggo, R M; Dodd, P J; Balloux, F
Epidemiology and public health planning will increasingly rely on the analysis of genetic sequence data. In particular, genetic data coupled with dates and locations of sampled isolates can be used to reconstruct the spatiotemporal dynamics of pathogens during outbreaks. Thus far, phylogenetic methods have been used to tackle this issue. Although these approaches have proved useful for informing on the spread of pathogens, they do not aim at directly reconstructing the underlying transmission tree. Instead, phylogenetic models infer most recent common ancestors between pairs of isolates, which can be inadequate for densely sampled recent outbreaks, where the sample includes ancestral and descendent isolates. In this paper, we introduce a novel method based on a graph approach to reconstruct transmission trees directly from genetic data. Using simulated data, we show that our approach can efficiently reconstruct genealogies of isolates in situations where classical phylogenetic approaches fail to do so. We then illustrate our method by analyzing data from the early stages of the swine-origin A/H1N1 influenza pandemic. Using 433 isolates sequenced at both the hemagglutinin and neuraminidase genes, we reconstruct the likely history of the worldwide spread of this new influenza strain. The presented methodology opens new perspectives for the analysis of genetic data in the context of disease outbreaks.
Manitz, Juliane; Kneib, Thomas; Schlather, Martin; Helbing, Dirk; Brockmann, Dirk
The key challenge during food-borne disease outbreaks, e.g. the 2011 EHEC/HUS outbreak in Germany, is the design of efficient mitigation strategies based on a timely identification of the outbreak's spatial origin. Standard public health procedures typically use case-control studies and tracings along food shipping chains. These methods are time-consuming and suffer from biased data collected slowly in patient interviews. Here we apply a recently developed, network-theoretical method to identify the spatial origin of food-borne disease outbreaks. Thereby, the network captures the transportation routes of contaminated foods. The technique only requires spatial information on case reports regularly collected by public health institutions and a model for the underlying food distribution network. The approach is based on the idea of replacing the conventional geographic distance with an effective distance that is derived from the topological structure of the underlying food distribution network. We show that this approach can efficiently identify most probable epicenters of food-borne disease outbreaks. We assess and discuss the method in the context of the 2011 EHEC epidemic. Based on plausible assumptions on the structure of the national food distribution network, the approach can correctly localize the origin of the 2011 German EHEC/HUS outbreak.
Elvira Partida, L; Fernández, M; Gutiérrez, J; Esnal, A; Benavides, J; Pérez, V; de la Torre, A; Álvarez, M; Esperón, F
Outbreaks of abortions and lambs born with nervous clinical signs and/or congenital malformations affected different sheep farms in Spain. Initial diagnosis of 'border disease-like' was established, based on clinical signs, serology and/or RNA detection by a pan-pestivirus RT-PCR. However, further investigation using immunohistochemical and molecular techniques identified BVDV-2b as the aetiological agent.
Hampton, Lee M; Garrison, Laurel; Kattan, Jessica; Brown, Ellen; Kozak-Muiznieks, Natalia A; Lucas, Claressa; Fields, Barry; Fitzpatrick, Nicole; Sapian, Luis; Martin-Escobar, Teresa; Waterman, Stephen; Hicks, Lauri A; Alpuche-Aranda, Celia; Lopez-Gatell, Hugo
Background. A Legionnaires' disease (LD) outbreak at a resort on Cozumel Island in Mexico was investigated by a joint Mexico-United States team in 2010. This is the first reported LD outbreak in Mexico, where LD is not a reportable disease. Methods. Reports of LD among travelers were solicited from US health departments and the European Working Group for Legionella Infections. Records from the resort and Cozumel Island health facilities were searched for possible LD cases. In April 2010, the resort was searched for possible Legionella exposure sources. The temperature and total chlorine of the water at 38 sites in the resort were measured, and samples from those sites were tested for Legionella. Results. Nine travelers became ill with laboratory-confirmed LD within 2 weeks of staying at the resort between May 2008 and April 2010. The resort and its potable water system were the only common exposures. No possible LD cases were identified among resort workers. Legionellae were found to have extensively colonized the resort's potable water system. Legionellae matching a case isolate were found in the resort's potable water system. Conclusions. Medical providers should test for LD when treating community-acquired pneumonia that is severe or affecting patients who traveled in the 2 weeks before the onset of symptoms. When an LD outbreak is detected, the source should be identified and then aggressively remediated. Because LD can occur in tropical and temperate areas, all countries should consider making LD a reportable disease if they have not already done so.
Hampton, Lee M.; Garrison, Laurel; Kattan, Jessica; Brown, Ellen; Kozak-Muiznieks, Natalia A.; Lucas, Claressa; Fields, Barry; Fitzpatrick, Nicole; Sapian, Luis; Martin-Escobar, Teresa; Waterman, Stephen; Hicks, Lauri A.; Alpuche-Aranda, Celia; Lopez-Gatell, Hugo
Background. A Legionnaires' disease (LD) outbreak at a resort on Cozumel Island in Mexico was investigated by a joint Mexico-United States team in 2010. This is the first reported LD outbreak in Mexico, where LD is not a reportable disease. Methods. Reports of LD among travelers were solicited from US health departments and the European Working Group for Legionella Infections. Records from the resort and Cozumel Island health facilities were searched for possible LD cases. In April 2010, the resort was searched for possible Legionella exposure sources. The temperature and total chlorine of the water at 38 sites in the resort were measured, and samples from those sites were tested for Legionella. Results. Nine travelers became ill with laboratory-confirmed LD within 2 weeks of staying at the resort between May 2008 and April 2010. The resort and its potable water system were the only common exposures. No possible LD cases were identified among resort workers. Legionellae were found to have extensively colonized the resort's potable water system. Legionellae matching a case isolate were found in the resort's potable water system. Conclusions. Medical providers should test for LD when treating community-acquired pneumonia that is severe or affecting patients who traveled in the 2 weeks before the onset of symptoms. When an LD outbreak is detected, the source should be identified and then aggressively remediated. Because LD can occur in tropical and temperate areas, all countries should consider making LD a reportable disease if they have not already done so. PMID:27704023
Brown, A C; Grass, J E; Richardson, L C; Nisler, A L; Bicknese, A S; Gould, L H
Although most non-typhoidal Salmonella illnesses are self-limiting, antimicrobial treatment is critical for invasive infections. To describe resistance in Salmonella that caused foodborne outbreaks in the United States, we linked outbreaks submitted to the Foodborne Disease Outbreak Surveillance System to isolate susceptibility data in the National Antimicrobial Resistance Monitoring System. Resistant outbreaks were defined as those linked to one or more isolates with resistance to at least one antimicrobial drug. Multidrug resistant (MDR) outbreaks had at least one isolate resistant to three or more antimicrobial classes. Twenty-one per cent (37/176) of linked outbreaks were resistant. In outbreaks attributed to a single food group, 73% (16/22) of resistant outbreaks and 46% (31/68) of non-resistant outbreaks were attributed to foods from land animals (P < 0·05). MDR Salmonella with clinically important resistance caused 29% (14/48) of outbreaks from land animals and 8% (3/40) of outbreaks from plant products (P < 0·01). In our study, resistant Salmonella infections were more common in outbreaks attributed to foods from land animals than outbreaks from foods from plants or aquatic animals. Antimicrobial susceptibility data on isolates from foodborne Salmonella outbreaks can help determine which foods are associated with resistant infections.
CDC is assisting ministries of health and working with other organizations to control and end the ongoing outbreak of Ebola virus disease (Ebola) in West Africa. The updated data in this report were compiled from ministry of health situation reports and World Health Organization (WHO) sources. Total case counts include all suspected, probable, and confirmed cases as defined by each country. These data reflect reported cases, which make up an unknown proportion of all actual cases. The data also reflect reporting delays that might vary from country to country.
CDC is assisting ministries of health and working with other organizations to control and end the ongoing outbreak of Ebola virus disease (Ebola) in West Africa. The updated data in this report were compiled from situation reports from the Guinea Interministerial Committee for Response Against the Ebola Virus and the World Health Organization, the Liberia Ministry of Health and Social Welfare, and the Sierra Leone Ministry of Health and Sanitation. Total case counts include all suspected, probable, and confirmed cases as defined by each country. These data reflect reported cases, which make up an unknown proportion of all actual cases and reporting delays that vary from country to country.
Ridpath, J F; Bayles, D O; Neill, J D; Falkenberg, S M; Bauermann, F V; Holler, L; Braun, L J; Young, D B; Kane, S E; Chase, C C L
Exposure to bovine viral diarrhea viruses (BVDV) results in acute and persistent infections. Persistent infections result from in utero exposure during the first trimester of gestation. Clinical presentation, in persistently infected cattle (PI), is highly variable. The reasons for this variation is largely unknown. The BVDV circulating in PI exist as quasispecies (swarms of individual viruses). An outbreak resulting in 34 PI cattle presented an opportunity to compare a large number of PI׳s. Methods were developed to compare the circulating viral populations within PI animals. It was found that PI animals generated in the same outbreak carry circulating viral populations that differ widely in size and diversity. Further, it was demonstrated that variation in PI viral populations could be used as a quantifiable phenotype. This observation makes it possible to test the correlation of this phenotype to other phenotypes such as growth rate, congenital defects, viral shed and cytokine expression.
Kroschewski, K; Kramer, M; Micklich, A; Staubach, C; Carmanns, R; Conraths, F J
In this era of globalisation the effective control of animal disease outbreaks requires powerful crisis management tools. In the 1990s software packages for different sectors of the government and agricultural industry began to be developed. In 2004, as a special application for tracking the movement of animals and animal products, the European Union developed the Trade Control and Expert System (TRACES) on the basis of its predecessor, the ANImal MOvement (ANIMO) project. The nationwide use of the ANIMO system by the veterinary authorities in Germany marked the beginning of the development in 1993 of a computerised national animal disease reporting system--the TierSeuchenNachrichten (TSN)--using the ANIMO hardware and software components. In addition to TRACES and TSN the third pillar for the management of animal disease outbreaks and crises in Germany is the national cattle and swine database--called Herkunftssicherungs- und Informationssystem für Tiere. A high degree of standardisation is necessary when integrating the different solutions at all levels of government and with the private sector. In this paper, the authors describe the use of these tools on the basis of their experience and in relation to what we can do now and what we should opt for in the future.
Fähnrich, C; Denecke, K; Adeoye, O O; Benzler, J; Claus, H; Kirchner, G; Mall, S; Richter, R; Schapranow, M P; Schwarz, N; Tom-Aba, D; Uflacker, M; Poggensee, G; Krause, G
In the context of controlling the current outbreak of Ebola virus disease (EVD), the World Health Organization claimed that 'critical determinant of epidemic size appears to be the speed of implementation of rigorous control measures', i.e. immediate follow-up of contact persons during 21 days after exposure, isolation and treatment of cases, decontamination, and safe burials. We developed the Surveillance and Outbreak Response Management System (SORMAS) to improve efficiency and timeliness of these measures. We used the Design Thinking methodology to systematically analyse experiences from field workers and the Ebola Emergency Operations Centre (EOC) after successful control of the EVD outbreak in Nigeria. We developed a process model with seven personas representing the procedures of EVD outbreak control. The SORMAS system architecture combines latest In-Memory Database (IMDB) technology via SAP HANA (in-memory, relational database management system), enabling interactive data analyses, and established SAP cloud tools, such as SAP Afaria (a mobile device management software). The user interface consists of specific front-ends for smartphones and tablet devices, which are independent from physical configurations. SORMAS allows real-time, bidirectional information exchange between field workers and the EOC, ensures supervision of contact follow-up, automated status reports, and GPS tracking. SORMAS may become a platform for outbreak management and improved routine surveillance of any infectious disease. Furthermore, the SORMAS process model may serve as framework for EVD outbreak modeling.
Pavone, Silvia; Salamida, Sonia; Pecorelli, Ivan; Rossi, Elisabetta; Manuali, Elisabetta
A widespread deadly outbreak occurred in captive birds belonging to the family Turdidae in Italy. The present study was performed on 46 dead birds coming from 3 small decoy-bird breeders in central Italy. Only Turdus pilaris, Turdus iliacus, Turdus philomelos and Turdus merula were affected. No other species of bird held by these breeders died. A change of diet before the hunting season was reported from all breeders. Full necropsy of the animals and histological investigations of representative tissue samples were performed. Microscopical examination showed marked iron deposits in liver samples. Bacteriological investigations and molecular analysis to exclude bacterial and viral diseases were carried out. Contamination of food pellet samples by mycotoxins and analysis to detect heavy metal contaminants in food pellet samples were considered. An interesting result was the high iron content found in food pellets. It was higher than that considered suitable for birds, especially for species susceptible to development iron storage disease (ISD). Taken together, the results suggested an outbreak of ISD caused by the high iron content of food given to the birds before the hunting season. The high mortality recorded only in species belonging to the family Turdidae suggests a genetic predisposition in the affected birds.
PAVONE, Silvia; SALAMIDA, Sonia; PECORELLI, Ivan; ROSSI, Elisabetta; MANUALI, Elisabetta
ABSTRACT A widespread deadly outbreak occurred in captive birds belonging to the family Turdidae in Italy. The present study was performed on 46 dead birds coming from 3 small decoy-bird breeders in central Italy. Only Turdus pilaris, Turdus iliacus, Turdus philomelos and Turdus merula were affected. No other species of bird held by these breeders died. A change of diet before the hunting season was reported from all breeders. Full necropsy of the animals and histological investigations of representative tissue samples were performed. Microscopical examination showed marked iron deposits in liver samples. Bacteriological investigations and molecular analysis to exclude bacterial and viral diseases were carried out. Contamination of food pellet samples by mycotoxins and analysis to detect heavy metal contaminants in food pellet samples were considered. An interesting result was the high iron content found in food pellets. It was higher than that considered suitable for birds, especially for species susceptible to development iron storage disease (ISD). Taken together, the results suggested an outbreak of ISD caused by the high iron content of food given to the birds before the hunting season. The high mortality recorded only in species belonging to the family Turdidae suggests a genetic predisposition in the affected birds. PMID:24920545
Background Diarrheal illness remains a leading cause of global morbidity and mortality, with the majority of deaths occurring in children <5 years of age. Lack of resources often prohibits the evaluation of outbreak characteristics and limits progress in managing this important disease syndrome, particularly in Africa. Relying only on existing medical staff and hospital resources, we assess the use of a questionnaire survey tool to identify baseline outbreak characteristics during recurrent diarrheal outbreaks in Chobe, Botswana. Methods Using historical surveillance data (2006–2009), the temporal pattern of recurrent diarrheal outbreaks was evaluated among patients <5 years of age presenting to health facilities in Chobe District. Using a questionnaire survey tool, medical staff from selected health facilities assessed patients (all ages) presenting with diarrheal disease during two diarrheal outbreaks (2011–2012). Cluster analysis and classification and regression trees (CART) were used to evaluate patient attributes by outbreak. Results We identified a bimodal, annual pattern of acute diarrhea in children <5 years of age across years (Wilcox test, W = 456.5, p = 0.052). Historical outbreak periods appeared to coincide with major hydrological phenomena (rainfall/flood recession). Across health facilities, a significant percent of patients in the prospective study were in the ≥5 age class (44%, n = 515 and 35%, n = 333 in the dry and wet season outbreaks, respectively). Cluster analysis of questionnaire data identified two main branches associated with patient age (<5 and ≥5 years of age). Patients did not cluster by outbreak or village. CART examination identified sex and hospitalization as being most predictive of patients <5 years and household diarrhea in patients ≥5 years. Water shortages and water quality deficiencies were identified in both outbreaks. Conclusions Diarrhea is a persistent, seasonally occurring disease in Chobe
Advances in water management and sanitation have reduced waterborne disease in the United States, although outbreaks continue to occur. Public health agencies in the U.S. states and territories* report information on waterborne disease outbreaks to the CDC Waterborne Disease and ...
Molecular epidemiology is a science which utilizes molecular biology to define the distribution of disease in a population (descriptive epidemiology) and relies heavily on integration of traditional (or analytical) epidemiological approaches to identify the etiological determinants of this distribution. The study of viral pathogens of aquaculture has provided many exciting opportunities to apply such tools. This review considers the extent to which molecular epidemiological studies have contributed to better understanding and control of disease in aquaculture, drawing on examples of viral diseases of salmonid fish of commercial significance including viral haemorrhagic septicaemia virus (VHSV), salmonid alphavirus (SAV) and infectious salmon anaemia virus (ISAV). Significant outcomes of molecular epidemiological studies include:Improved taxonomic classification of viruses. A better understanding of the natural distribution of viruses. An improved understanding of the origins of viral pathogens in aquaculture. An improved understanding of the risks of translocation of pathogens outwith their natural host range. An increased ability to trace the source of new disease outbreaks. Development of a basis for ensuring development of appropriate diagnostic tools. An ability to classify isolates and thus target future research aimed at better understanding biological function. While molecular epidemiological studies have no doubt already made a significant contribution in these areas, the advent of new technologies such as pyrosequencing heralds a quantum leap in the ability to generate descriptive molecular sequence data. The ability of molecular epidemiology to fulfil its potential to translate complex disease pathways into relevant fish health policy is thus unlikely to be limited by the generation of descriptive molecular markers. More likely, full realisation of the potential to better explain viral transmission pathways will be dependent on the ability to assimilate
Background Haff disease is unexplained rhabdomyolysis caused by consumption of fishery products in the previous 24 h. It was first identified in Europe in 1924 but the condition is extremely rare in China. Here we describe a past outbreak of acute food borne muscle poisoning that occurred in Guangdong Province (South China) in 2009. Methods The first full outbreak of Haff disease reported in Jiangsu Province (East China) in 2010, indicated that the incidence of the disease may be increasing in China. We, therefore first retrospectively reviewed epidemiologic, trace-back, environmental studies, and laboratory analyses, including oral toxicity testing to ascertain risk and chemical analysis to identify toxin(s), from the 2009 Guangdong outbreak. Then we compared data from the 2009 outbreak with data from all other Haff disease outbreaks that were available. Results Clinical symptoms and laboratory findings indicated that the 2009 Guangdong outbreak disease was consistent with rhabdomyolysis. Epidemiologic, trace-back, environmental studies and laboratory analyses implied that the disease was caused by freshwater Pomfrets consumed prior to the onset of symptoms. We also identified common factors between the 2009 Guangdong outbreak and previous Haff disease outbreaks reported around the world, while as with other similar outbreaks, the exact etiological factor(s) of the disease remains unknown. Conclusions The 2009 Guangdong outbreak of ‘muscle poisoning’ was retrospectively identified as an outbreak of Haff disease. This comprised the highest number of cases reported in China thus far. Food borne diseases emerging in this unusual form and the irregular pattern of outbreaks present an ongoing public health risk, highlighting the need for improved surveillance and diagnostic methodology. PMID:23642345
Bianchi, M V; Konradt, G; de Souza, S O; Bassuino, D M; Silveira, S; Mósena, A C S; Canal, C W; Pavarini, S P; Driemeier, D
Bovine viral diarrhea virus (BVDV) belongs to the Pestivirus genus, which is further divided into subgenotypes (1a-1u and 2a-c). When persistent infection occurs, the calf will be immunotolerant to BVDV and possibly develop mucosal disease. This study describes an outbreak of BVDV-1d-induced mucosal disease lacking intestinal lesions. Eleven calves presented with anorexia, sialorrhea, lameness, recumbency, and death. Three calves were necropsied, showing ulceration of the interdigital skin and the oral and nasal mucosa; linear ulcers in the tongue, esophagus, and rumen; and rounded ulcers in the abomasum. Microscopically, mucosa and skin had superficial necrosis, with single-cell necrosis and vacuolation in epithelial cells, and severe parakeratosis. Immunohistochemistry (IHC) showed BVDV antigen in the cytoplasm of epithelial cells in skin and mucosa. All 11 dead calves were positive upon reverse transcription-polymerase chain reaction (RT-PCR) for the detection of Pestivirus along with another 11 live calves from the herd, which were positive again by RT-PCR and IHC after a 4-week interval. Sequencing of the 5' untranslated region and N-terminal protease showed that viruses from these 22 calves were homologous and of subgenotype BVDV-1d. Cytopathic BVDV was isolated from 8 of 11 dead calves, but only noncytopathic BVDV was isolated from the 11 live animals. The findings indicate that this was an outbreak of mucosal disease caused by BVDV-1d, with high morbidity, and lesions restricted to the upper alimentary system and skin and absent from intestine. Thus, the epidemiological and pathological features in this form of mucosal disease may be similar to vesicular diseases, including foot and mouth disease.
Rooney, Roisin M.; Cramer, Elaine H.; Mantha, Stacey; Nichols, Gordon; Bartram, Jamie K.; Farber, Jeffrey M.; Benembarek, Peter K.
OBJECTIVE: Foodborne disease outbreaks on ships are of concern because of their potentially serious health consequences for passengers and crew and high costs to the industry. The authors conducted a review of outbreaks of foodborne diseases associated with passenger ships in the framework of a World Health Organization project on setting guidelines for ship sanitation. METHODS: The authors reviewed data on 50 outbreaks of foodborne disease associated with passenger ships. For each outbreak, data on pathogens/toxins, type of ship, factors contributing to outbreaks, mortality and morbidity, and food vehicles were collected. RESULTS: The findings of this review show that the majority of reported outbreaks were associated with cruise ships and that almost 10,000 people were affected. Salmonella spp were most frequently associated with outbreaks. Foodborne outbreaks due to enterotoxigenic E. coli spp, Shigella spp, noroviruses (formally called Norwalk-like viruses), Vibrio spp, Staphylococcus aureus, Clostridium perfringens, Cyclospora sp, and Trichinella sp also occurred on ships. Factors associated with the outbreaks reviewed include inadequate temperature control, infected food handlers, contaminated raw ingredients, cross-contamination, inadequate heat treatment, and onshore excursions. Seafood was the most common food vehicle implicated in outbreaks. CONCLUSIONS: Many ship-associated outbreaks could have been prevented if measures had been taken to ensure adequate temperature control, avoidance of cross-contamination, reliable food sources, adequate heat treatment, and exclusion of infected food handlers from work. PMID:15219800
Gardy, Jennifer L; Naus, Monika; Amlani, Ashraf; Chung, Walter; Kim, Hochan; Tan, Malcolm; Severini, Alberto; Krajden, Mel; Puddicombe, David; Sahni, Vanita; Hayden, Althea S; Gustafson, Reka; Henry, Bonnie; Tang, Patrick
We used whole-genome sequencing to investigate a dual-genotype outbreak of measles occurring after the XXI Olympic Winter Games in Vancouver, Canada. By sequencing 27 complete genomes from H1 and D8 genotype measles viruses isolated from outbreak cases, we estimated the virus mutation rate, determined that person-to-person transmission is typically associated with 0 mutations between isolates, and established that a single introduction of H1 virus led to the expansion of the outbreak beyond Vancouver. This is the largest measles genomics project to date, revealing novel aspects of measles virus genetics and providing new insights into transmission of this reemerging viral pathogen.
In 2006, we collected 12203 biting flies from a vesicular stomatitis outbreak in Natrona County, Wyoming. Flies were identified to the species level and viruses were isolated and identified by RT-PCR. We detected vesicular stomatitis virus-New Jersey serotype in two pools of Simulium bivittatum, W...
McDonnell, R J; Wall, P G; Adak, G K; Evans, H S; Cowden, J M; Caul, E O
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.
Golde, William T; Pacheco, Juan M; Duque, Hernando; Doel, Timothy; Penfold, Barry; Ferman, Geoffrey S; Gregg, Douglas R; Rodriguez, Luis L
Recent outbreaks of foot-and-mouth disease virus (FMDV) demonstrate that this highly contagious viral infection of cloven hoofed animals continues to be a significant economic problem worldwide. Debate about the most effective way to respond to outbreaks of FMDV in disease free countries continues to center on the use of vaccines. In this report, we present data showing that a commercially available, standard dose vaccine formulation can fully protect cattle against direct challenge with the virus in as little as 7 days with no carrier transmission to naïve animals. Cattle challenged 4 days after vaccination have reduced disease severity, no detectable virus in blood and little virus shedding from nasal secretions. These significant effects at 4 days post vaccination, confirmed in two separate trials, support the value of using currently available vaccines as a first line of defense against foot-and-mouth disease (FMD) outbreaks.
Barr, B.C.; Jessup, David A.; Docherty, Douglas E.; Lownestine, L.J.
Several muscovy ducks from a free-roaming flock of 65 muscovy and mallard ducks died over a 3-week period. Three muscovy ducks were necropsied. Gross and microscopic changes were compatible with duck virus enteritis, and the virus was isolated. In addition to intranuclear viral inclusion bodies in several tissues, intracytoplasmic inclusion bodies were present in esophageal and cloacal epithelium, By electron microscopy, the membrane-bound intracytoplasmic inclusions were found to contain enveloped herpesvirus, and nuclei contained herpes viral nucleocapsids.
Lee, Jong-Kyung; Kwak, No-Seong; Kim, Hyun Jung
This study systemically analyzed data on the prevalence of foodborne pathogens and foodborne disease outbreaks to identify the priorities of foodborne infection risk management in Korea. Multiple correspondence analysis was applied to three variables: origin of food source, phase of food supply chain, and 12 pathogens using 358 cases from 76 original papers and official reports published in 1998-2012. In addition, correspondence analysis of two variables--place and pathogen--was conducted based on epidemiological data of 2357 foodborne outbreaks in 2002-2011 provided by the Korean Ministry of Food and Drug Safety. The results of this study revealed three distinct areas of food monitoring: (1) livestock-derived raw food contaminated with Campylobacter spp., pathogenic Escherichia coli, Salmonella spp., and Listeria monocytogenes; (2) multi-ingredient and ready-to-eat food related to Staphylococcus aureus; and (3) water associated with norovirus. Our findings emphasize the need to track the sources and contamination pathways of foodborne pathogens for more effective risk management.
Eubank, Stephen; Guclu, Hasan; Anil Kumar, V. S.; Marathe, Madhav V.; Srinivasan, Aravind; Toroczkai, Zoltán; Wang, Nan
Most mathematical models for the spread of disease use differential equations based on uniform mixing assumptions or ad hoc models for the contact process. Here we explore the use of dynamic bipartite graphs to model the physical contact patterns that result from movements of individuals between specific locations. The graphs are generated by large-scale individual-based urban traffic simulations built on actual census, land-use and population-mobility data. We find that the contact network among people is a strongly connected small-world-like graph with a well-defined scale for the degree distribution. However, the locations graph is scale-free, which allows highly efficient outbreak detection by placing sensors in the hubs of the locations network. Within this large-scale simulation framework, we then analyse the relative merits of several proposed mitigation strategies for smallpox spread. Our results suggest that outbreaks can be contained by a strategy of targeted vaccination combined with early detection without resorting to mass vaccination of a population.
Knust, Barbara; Schafer, Ilana J; Wamala, Joseph; Nyakarahuka, Luke; Okot, Charles; Shoemaker, Trevor; Dodd, Kimberly; Gibbons, Aridth; Balinandi, Stephen; Tumusiime, Alex; Campbell, Shelley; Newman, Edmund; Lasry, Estrella; DeClerck, Hilde; Boum, Yap; Makumbi, Issa; Bosa, Henry Kyobe; Mbonye, Anthony; Aceng, Jane Ruth; Nichol, Stuart T; Ströher, Ute; Rollin, Pierre E
In October 2012, a cluster of illnesses and deaths was reported in Uganda and was confirmed to be an outbreak of Marburg virus disease (MVD). Patients meeting the case criteria were interviewed using a standard investigation form, and blood specimens were tested for evidence of acute or recent Marburg virus infection by reverse transcription-polymerase chain reaction (RT-PCR) and antibody enzyme-linked immunosorbent assay. The total count of confirmed and probable MVD cases was 26, of which 15 (58%) were fatal. Four of 15 laboratory-confirmed cases (27%) were fatal. Case patients were located in 4 different districts in Uganda, although all chains of transmission originated in Ibanda District, and the earliest case detected had an onset in July 2012. No zoonotic exposures were identified. Symptoms significantly associated with being a MVD case included hiccups, anorexia, fatigue, vomiting, sore throat, and difficulty swallowing. Contact with a case patient and attending a funeral were also significantly associated with being a case. Average RT-PCR cycle threshold values for fatal cases during the acute phase of illness were significantly lower than those for nonfatal cases. Following the institution of contact tracing, active case surveillance, care of patients with isolation precautions, community mobilization, and rapid diagnostic testing, the outbreak was successfully contained 14 days after its initial detection.
Grass, Julian E; Gould, L Hannah; Mahon, Barbara E
Clostridium perfringens is estimated to be the second most common bacterial cause of foodborne illness in the United States, causing one million illnesses each year. Local, state, and territorial health departments voluntarily report C. perfringens outbreaks to the U.S. Centers for Disease Control and Prevention through the Foodborne Disease Outbreak Surveillance System. Our analysis included outbreaks confirmed by laboratory evidence during 1998-2010. A food item was implicated if C. perfringens was isolated from food or based on epidemiologic evidence. Implicated foods were classified into one of 17 standard food commodities when possible. From 1998 to 2010, 289 confirmed outbreaks of C. perfringens illness were reported with 15,208 illnesses, 83 hospitalizations, and eight deaths. The number of outbreaks reported each year ranged from 16 to 31 with no apparent trend over time. The annual number of outbreak-associated illnesses ranged from 359 to 2,173, and the median outbreak size was 24 illnesses. Outbreaks occurred year round, with the largest number in November and December. Restaurants (43%) were the most common setting of food preparation. Other settings included catering facility (19%), private home (16%), prison or jail (11%), and other (10%). Among the 144 (50%) outbreaks attributed to a single food commodity, beef was the most common commodity (66 outbreaks, 46%), followed by poultry (43 outbreaks, 30%), and pork (23 outbreaks, 16%). Meat and poultry outbreaks accounted for 92% of outbreaks with an identified single food commodity. Outbreaks caused by C. perfringens occur regularly, are often large, and can cause substantial morbidity yet are preventable if contamination of raw meat and poultry products is prevented at the farm or slaughterhouse or, after contamination, if these products are properly handled and prepared, particularly in restaurants and catering facilities.
Towner, Jonathan S; Rollin, Pierre E; Bausch, Daniel G; Sanchez, Anthony; Crary, Sharon M; Vincent, Martin; Lee, William F; Spiropoulou, Christina F; Ksiazek, Thomas G; Lukwiya, Mathew; Kaducu, Felix; Downing, Robert; Nichol, Stuart T
The largest outbreak on record of Ebola hemorrhagic fever (EHF) occurred in Uganda from August 2000 to January 2001. The outbreak was centered in the Gulu district of northern Uganda, with secondary transmission to other districts. After the initial diagnosis of Sudan ebolavirus by the National Institute for Virology in Johannesburg, South Africa, a temporary diagnostic laboratory was established within the Gulu district at St. Mary's Lacor Hospital. The laboratory used antigen capture and reverse transcription-PCR (RT-PCR) to diagnose Sudan ebolavirus infection in suspect patients. The RT-PCR and antigen-capture diagnostic assays proved very effective for detecting ebolavirus in patient serum, plasma, and whole blood. In samples collected very early in the course of infection, the RT-PCR assay could detect ebolavirus 24 to 48 h prior to detection by antigen capture. More than 1,000 blood samples were collected, with multiple samples obtained from many patients throughout the course of infection. Real-time quantitative RT-PCR was used to determine the viral load in multiple samples from patients with fatal and nonfatal cases, and these data were correlated with the disease outcome. RNA copy levels in patients who died averaged 2 log(10) higher than those in patients who survived. Using clinical material from multiple EHF patients, we sequenced the variable region of the glycoprotein. This Sudan ebolavirus strain was not derived from either the earlier Boniface (1976) or Maleo (1979) strain, but it shares a common ancestor with both. Furthermore, both sequence and epidemiologic data are consistent with the outbreak having originated from a single introduction into the human population.
Simonen, Marja-Leena; Roivainen, Merja; Iber, Jane; Burns, Cara; Hovi, Tapani
In 1984, a wild type 3 poliovirus (PV3/FIN84) spread all over Finland causing nine cases of paralytic poliomyelitis and one case of aseptic meningitis. The outbreak was ended in 1985 with an intensive vaccination campaign. By limited sequence comparison with previously isolated PV3 strains, closest relatives of PV3/FIN84 were found among strains circulating in the Mediterranean region. Now we wanted to reanalyse the relationships using approaches currently exploited in poliovirus surveillance. Cell lysates of 22 strains isolated during the outbreak and stored frozen were subjected to RT-PCR amplification in three genomic regions without prior subculture. Sequences of the entire VP1 coding region, 150 nucleotides in the VP1-2A junction, most of the 5' non-coding region, partial sequences of the 3D RNA polymerase coding region and partial 3' non-coding region were compared within the outbreak and with sequences available in data banks. In addition, complete nucleotide sequences were obtained for 2 strains isolated from two different cases of disease during the outbreak. The results confirmed the previously described wide intraepidemic variation of the strains, including amino acid substitutions in antigenic sites, as well as the likely Mediterranean region origin of the strains. Simplot and bootscanning analyses of the complete genomes indicated complicated evolutionary history of the non-capsid coding regions of the genome suggesting several recombinations with different HEV-C viruses in the past.
Gould, L Hannah; Rosenblum, Ida; Nicholas, David; Phan, Quyen; Jones, Timothy F
An estimated 48 million cases of foodborne illness occur each year in the United States, resulting in approximately 128,000 hospitalizations and 3,000 deaths. Over half of all foodborne disease outbreaks reported to the Centers for Disease Control and Prevention are associated with eating in restaurants or delicatessens. We reviewed data from restaurant-associated foodborne disease outbreaks to better understand the factors that contribute to these outbreaks. Data on restaurant-associated foodborne disease outbreaks reported by sites participating in the Foodborne Diseases Active Surveillance Network (FoodNet) were analyzed to characterize contributing factors reported in foodborne disease outbreaks and the levels of evidence used to identify these factors. Of 457 foodborne disease outbreaks reported in 2006 and 2007 by FoodNet sites, 300 (66%) were restaurant associated, and of these 295 (98%) had at least one reported contributing factor. One to nine (with a median of two) contributing factors were reported per outbreak. Of the 257 outbreaks with a single etiology reported, contributing factors associated with food worker health and hygiene were reported for 165 outbreaks (64%), factors associated with food preparation practices within the establishment were reported for 88 outbreaks (34%), and factors associated with contamination introduced before reaching the restaurant were reported for 56 outbreaks (22%). The pronounced role of food workers in propagating outbreaks makes it clear that more work is needed to address prevention at the local level. Food workers should be instructed not to prepare food while ill to prevent the risk of transmitting pathogens.
Reactive oxygen species (ROS) are essential molecules for many physiological functions and act as second messengers in a large variety of tissues. An imbalance in the production and elimination of ROS is associated with human diseases including neurodegenerative disorders. In the last years the notion that neurodegenerative diseases are accompanied by chronic viral infections, which may result in an increase of neurodegenerative diseases progression, emerged. It is known in literature that enhanced viral infection risk, observed during neurodegeneration, is partly due to the increase of ROS accumulation in brain cells. However, the molecular mechanisms of viral infection, occurring during the progression of neurodegeneration, remain unclear. In this review, we discuss the recent knowledge regarding the role of influenza, herpes simplex virus type-1, and retroviruses infection in ROS/RNS-mediated Parkinson's disease (PD), Alzheimer's disease (AD), and amyotrophic lateral sclerosis (ALS). PMID:27110325
Dreyfus, David H
Many chronic human diseases may have an underlying autoimmune mechanism. In this review, the author presents a case of autoimmune CIU (chronic idiopathic urticaria) in stable remission after therapy with a retroviral integrase inhibitor, raltegravir (Isentress). Previous reports located using the search terms "autoimmunity" and "anti-viral" and related topics in the pubmed data-base are reviewed suggesting that novel anti-viral agents such as retroviral integrase inhibitors, gene silencing therapies and eventually vaccines may provide new options for anti-viral therapy of autoimmune diseases. Cited epidemiologic and experimental evidence suggests that increased replication of epigenomic viral pathogens such as Epstein-Barr Virus (EBV) in chronic human autoimmune diseases such as rheumatoid arthritis (RA), systemic lupus Erythematosus (SLE), and multiple sclerosis (MS) may activate endogenous human retroviruses (HERV) as a pathologic mechanism. Memory B cells are the reservoir of infection of EBV and also express endogenous retroviruses, thus depletion of memory b-lymphocytes by monoclonal antibodies (Rituximab) may have therapeutic anti-viral effects in addition to effects on B-lymphocyte presentation of both EBV and HERV superantigens. Other novel anti-viral therapies of chronic autoimmune diseases, such as retroviral integrase inhibitors, could be effective, although not without risk.
Ng, Lee-Ching; Chem, Yu-Kie; Koo, Carmen; Mudin, Rose Nani Binti; Amin, Faridah Mohd; Lee, Kim-Sung; Kheong, Chong Chee
Characterization of 14,079 circulating dengue viruses in a cross-border surveillance program, UNITEDengue, revealed that the 2013 outbreaks in Singapore and Malaysia were associated with replacement of predominant serotype. While the predominant virus in Singapore switched from DENV2 to DENV1, DENV2 became predominant in neighboring Malaysia. Dominance of DENV2 was most evident on the southern states where higher fatality rates were observed.
Ng, Lee-Ching; Chem, Yu-kie; Koo, Carmen; Mudin, Rose Nani Binti; Amin, Faridah Mohd; Lee, Kim-Sung; Kheong, Chong Chee
Characterization of 14,079 circulating dengue viruses in a cross-border surveillance program, UNITEDengue, revealed that the 2013 outbreaks in Singapore and Malaysia were associated with replacement of predominant serotype. While the predominant virus in Singapore switched from DENV2 to DENV1, DENV2 became predominant in neighboring Malaysia. Dominance of DENV2 was most evident on the southern states where higher fatality rates were observed. PMID:25846296
Greenhouse tomato productions in North America have suffered from several high profile viroid disease outbreaks in recent years. In this presentation, I will summarize and briefly describe each of these viroid disease outbreak and their relationship. What are viroids and their transmission through ...
Recent clusters of outbreaks of mosquito-borne diseases (Rift Valley fever and chikungunya) in Africa and parts of the Indian Ocean islands illustrate how interannual climate variability influences the changing risk patterns of disease outbreaks. Extremes in rainfall (drought and flood) during the p...
Elderd, Bret D; Reilly, James R
While rising global temperatures are increasingly affecting both species and their biotic interactions, the debate about whether global warming will increase or decrease disease transmission between individuals remains far from resolved. This may stem from the lack of empirical data. Using a tractable and easily manipulated insect host-pathogen system, we conducted a series of field and laboratory experiments to examine how increased temperatures affect disease transmission using the crop-defoliating pest, the fall armyworm (Spodoptera frugiperda) and its species-specific baculovirus, which causes a fatal infection. To examine the effects of temperature on disease transmission in the field, we manipulated baculovirus density and temperature. As infection occurs when a host consumes leaf tissue on which the pathogen resides, baculovirus density was controlled by placing varying numbers of infected neonate larvae on experimental plants. Temperature was manipulated by using open-top chambers (OTCs). The laboratory experiments examined how increased temperatures affect fall armyworm feeding and development rates, which provide insight into how host feeding behaviour and physiology may affect transmission. Disease transmission and outbreak intensity, measured as the cumulative fraction infected during an epizootic, increased at higher temperatures. However, there was no appreciable change in the mean transmission rate of the disease, which is often the focus of empirical and theoretical research. Instead, the coefficient of variation (CV) associated with the transmission rate shrunk. As the CV decreased, heterogeneity in disease risk across individuals declined, which resulted in an increase in outbreak intensity. In the laboratory, increased temperatures increased feeding rates and decreased developmental times. As the host consumes the virus along with the leaf tissue on which it resides, increased feeding rate is likely to increase the probability of an individual
The frequency and magnitude of recognized and declared filovirus-disease outbreaks have increased in recent years, while pathogenic filoviruses are potentially ubiquitous throughout sub-Saharan Africa. Meanwhile, the efficiency and effectiveness of filovirus-disease outbreak preparedness and response efforts are currently limited by inherent challenges and persistent shortcomings. This paper delineates some of these challenges and shortcomings and provides a proposal for enhancing future filovirus-disease outbreak preparedness and response. The proposal serves as a call for prompt action by the organizations that comprise filovirus-disease outbreak response teams, namely, Ministries of Health of outbreak-prone countries, the World Health Organization, Médecins Sans Frontières, the Centers for Disease Control and Prevention-Atlanta, and others.
Pinzón-Redondo, Hernando; Coronell-Rodriguez, Wilfrido; Díaz-Martinez, Inés; Guzmán-Corena, Ángel; Constenla, Dagna
ABSTRACT Meningococcal disease is a serious and potentially life-threatening infection that is caused by the bacterium Neisseria meningitidis (N. meningitidis), and it can cause meningitis, meningococcaemia outbreaks and epidemics. The disease is fatal in 9-12% of cases and with a death rate of up to 40% among patients with meningococcaemia. The objective of this study was to estimate the costs of a meningococcal outbreak that occurred in a Caribbean city of Colombia. We contacted experts involved in the outbreak and asked them specific questions about the diagnosis and treatment for meningococcal cases during the outbreak. Estimates of costs of the outbreak were also based on extensive review of medical records available during the outbreak. The costs associated with the outbreak were divided into the cost of the disease response phase and the cost of the disease surveillance phase. The costs associated with the outbreak control and surveillance were expressed in US$ (2011) as cost per 1,000 inhabitants. The average age of patients was 4.6 years (SD 3.5); 50% of the cases died; 50% of the cases were reported to have meningitis (3/6); 33% were diagnosed with meningococcaemia and myocarditis (2/6); 50% of the cases had bacteraemia (3/6); 66% of the cases had a culture specimen positive for Neisseria meningitidis; 5 of the 6 cases had RT-PCR positive for N. meningitidis. All N. meningitidis were serogroup B; 50 doses of ceftriaxone were administered as prophylaxis. Vaccine was not available at the time. The costs associated with control of the outbreak were estimated at US$ 0.8 per 1,000 inhabitants, disease surveillance at US$ 4.1 per 1,000 inhabitants, and healthcare costs at US$ 5.1 per 1,000 inhabitants. The costs associated with meningococcal outbreaks are substantial, and the outbreaks should be prevented. The mass chemoprophylaxis implemented helped control the outbreak. PMID:25395916
Bovine viral diarrhea virus (BVDV) genotype 1 subtype b caused an outbreak of premature births, late term abortions, brachygnathism, growth retardation, brain deformities and rare other skeletal deformities in Holstein calves born to first calf heifers on one dairy. Experimental challenge of three,...
Brinkmann, Annika; Nitsche, Andreas; Kohl, Claudia
Surveillance and monitoring of viral pathogens circulating in humans and wildlife, together with the identification of emerging infectious diseases (EIDs), are critical for the prediction of future disease outbreaks and epidemics at an early stage. It is advisable to sample a broad range of vertebrates and invertebrates at different temporospatial levels on a regular basis to detect possible candidate viruses at their natural source. However, virus surveillance systems can be expensive, costly in terms of finances and resources and inadequate for sampling sufficient numbers of different host species over space and time. Recent publications have presented the concept of a new virus surveillance system, coining the terms “flying biological syringes”, “xenosurveillance” and “vector-enabled metagenomics”. According to these novel and promising surveillance approaches, viral metagenomics on engorged mosquitoes might reflect the viral diversity of numerous mammals, birds and humans, combined in the mosquitoes’ blood meal during feeding on the host. In this review article, we summarize the literature on vector-enabled metagenomics (VEM) techniques and its application in disease surveillance in humans. Furthermore, we highlight the combination of VEM and “invertebrate-derived DNA” (iDNA) analysis to identify the host DNA within the mosquito midgut. PMID:27775568
Factors known to trigger the emergence or re-emergence of infectious diseases include globalisation, population growth, migration, international trade, urbanisation, forest destruction, climate change, loss of biodiversity, poverty, famine and war. Epidemics not only lead to disastrous loss of human life but may also have catastrophic economic, political and social consequences. Outbreaks may rapidly jeopardize industry, trade or tourism in countries that are unprepared. Dengue is currently spreading throughout the tropics, while another arbovirus, chikungunya, infected 30 to 75% of the population in some parts of the Indian Ocean region between 2005 and 2006. Chikungunya is now spreading through India, where more than a million people have so far been infected. This viral disease can cause lasting disability, and the first deaths were recently reported in La Réunion and Mayotte. All countries are at risk from emerging or re-emerging diseases, but the consequences are far worse in poor countries. Microbial pathogens and wild mammals, birds and arthropods do not respect man-made borders. There is still time to act against this threat of emerging and re-emerging infectious diseases, through prevention, anticipation, monitoring and research.
Background: Since 1978, CDC, EPA, and the Council of State and Territorial Epidemiologists have collaborated on the Waterborne Disease and Outbreak Surveillance System (WBDOSS) to capture data on waterborne disease outbreaks associated with recreational water. WBDOSS is the prima...
Problem/Condition: Since 1971, the Centers for Disease Control and Prevention (CDC), the U.S. Environmental Protection Agency (EPA), and the Council of State and Territorial Epidemiologists have maintained a collaborative Waterborne Disease and Outbreak Surveillance System (WBDOS...
Ferguson, Neil M.; Keeling, Matt J.; John Edmunds, W.; Gani, Raymond; Grenfell, Bryan T.; Anderson, Roy M.; Leach, Steve
Mathematical models of viral transmission and control are important tools for assessing the threat posed by deliberate release of the smallpox virus and the best means of containing an outbreak. Models must balance biological realism against limitations of knowledge, and uncertainties need to be accurately communicated to policy-makers. Smallpox poses the particular challenge that key biological, social and spatial factors affecting disease spread in contemporary populations must be elucidated largely from historical studies undertaken before disease eradication in 1979. We review the use of models in smallpox planning within the broader epidemiological context set by recent outbreaks of both novel and re-emerging pathogens.
Zhang, Shuo; Li, Dexin
Since Zika virus (ZIKV) has firstly been isolated in 1947, Uganda, outbreaks of Zika fever have been reported in many areas such as in Africa, Southeast Asia and America. Imported cases in China also have been reported. Zika virus belongs to the family Flaviviridae, genus Flavivirus, and include Africa subtype and Asia subtype. It is a mosquito-borne virus primarily transmitted by Aedes aegypti mosquitoes. Sexual transmission, Blood transmission and mother-to-fetus transmission were also reported. Zika virus can go though blood-brain barrier and infect central nervous system. Symptoms are generally mild and self-limited, but recent evidence suggests a possible association between maternal Zika virus infection and adverse fetal outcomes, such as congenital microcephaly, as well as a possible association with Guillain-Barré syndrome. Laboratorial Diagnosis includes nucleic acid detection, Serological test, and isolation of virus. Currently, no vaccine or medication exists to prevent or treat Zika virus infection. Preventive measures against Zika virus infection should be taken through prevention of mosquito bites and surveillance in epidemic area.
Schafer, Ilana J; Knudsen, Erik; McNamara, Lucy A; Agnihotri, Sachin; Rollin, Pierre E; Islam, Asad
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.
Harvey, R Reid; Zakhour, Christine M; Gould, L Hannah
Consumer demand for organically produced foods is increasing in the United States as well as globally. Consumer perception often credits organic foods as being safer than conventionally produced foods, although organic standards do not directly address safety issues such as microbial or chemical hazards. We reviewed outbreaks reported to the Centers for Disease Control and Prevention's Foodborne Disease Outbreak Surveillance System where the implicated food was reported to be organic. Information collected for each outbreak included the year, state, number of illnesses, pathogen, and implicated food. We identified 18 outbreaks caused by organic foods from 1992 to 2014, resulting in 779 illnesses, 258 hospitalizations, and 3 deaths; 56% of outbreaks occurred from 2010 to 2014. Nine outbreaks occurred in a single state, and nine outbreaks were multistate. Salmonella sp. (44% of outbreaks) and Escherichia coli O157:H7 (33%) were the most commonly occurring pathogens. Eight of the outbreaks were attributed to produce items, four to unpasteurized dairy products, two to eggs, two to nut and seed products, and two to multi-ingredient foods. Fifteen (83%) outbreaks were associated with foods that were definitely or likely U.S. Department of Agriculture certified. More foodborne outbreaks associated with organic foods in the United States have been reported in recent years, in parallel with increases in organic food production and consumption. We are unable to assess risk of outbreaks due to organic foods compared with conventional foods because foodborne outbreak surveillance does not systematically collect food production method. Food safety requires focused attention by consumers, regardless of whether foods are produced organically or conventionally. Consumers should be aware of the risk of milk and produce consumed raw, including organic.
Grenón, S L; Robledo, M L; von Specht, M H; Cisterna, D M; Lema, C L; Freire, M C
A descriptive retrospective study was carried out to describe an epidemic outbreak of enteroviral meningitis in Misiones. We reviewed records of 143 children from 1 month to 14 years of age who were hospitalized with aseptic meningitis in the Pediatric Hospital of Posadas from August to December 2005. Increased number of cases was observed between weeks 33 to 50 which reached a maximum peak in weeks 47 and 48, confirming an outbreak. The median of age was 8 years old, 55.2% were males. Eighty percent of cases were in 5 to 14 years old children. The average length of time spent in the hospital was 4.5+/-1.7 days, no deaths were reported. We performed cell counts, chemical and bacterial studies of CSF, and culture or RT-Nested/PCR for enteroviruses. Isolates were serotyped by RT-PCR amplification and genetic sequencing. Cell counts were from 6 to 5040 cells/mm3. Ninety two percent had less than 500 cells/mm3 and 43.5% had lymphocyte predominance. Glucose levels were normal with slightly elevated protein counts in 56% of cases. Of the cultured samples, 28% (17/60) showed cytopathic effect compatible with enterovirus. RT-n-PCR detected enterovirus in 73% (43/59) of the analyzed CSF. Echovirus type 4 was identified in 6 of them. The positive indicator obtained by combining both techniques was 83% (58/70).
Known pathogens cause an estimated 9.4 million foodborne illnesses annually in the United States. CDC collects data on foodborne disease outbreaks submitted by all states, the District of Columbia, and Puerto Rico through CDC's Foodborne Disease Outbreak Surveillance System. Data reported for each outbreak include the number of illnesses, hospitalizations, and deaths; the etiologic agent; the implicated food vehicle; and other factors involved in food preparation and consumption. During 2009-2010, a total of 1,527 foodborne disease outbreaks (675 in 2009 and 852 in 2010) were reported, resulting in 29,444 cases of illness, 1,184 hospitalizations, and 23 deaths. Among the 790 outbreaks with a single laboratory-confirmed etiologic agent, norovirus was the most commonly reported, accounting for 42% of outbreaks. Salmonella was second, accounting for 30% of outbreaks. Among the 299 outbreaks attributed to a food composed of ingredients from one of 17 predefined, mutually exclusive food commodities, those most often implicated were beef (13%), dairy (12%), fish (12%), and poultry (11%). The commodities in the 299 outbreaks associated with the most illnesses were eggs (27% of illnesses), beef (11%), and poultry (10%). Public health, regulatory, and food industry professionals can use this information when creating targeted control strategies along the farm-to-table continuum for specific agents, specific foods, and specific pairs of agents and foods. This information also supports efforts to promote safe food-handling practices among food workers and the public.
Chen, M M; Tan, Y; Tang, Z Z; Lin, M; Zhou, K J; He, W T; Yang, Y P; Wang, J
Objective: To understand the epidemiological characteristics and viral sources of dengue fever outbreak in Guangxi Zhuang Autonomous Region (Guangxi) in 2014. Methods: A combined analysis of epidemiological characteristics and genetic characteristics were performed in this study. The time, population and area distributions of the cases were analyzed. Serum samples were collected from dengue fever cases to detect NS1 antigen by using commercial ELISA kits according to the guideline of the manufacture. RT-PCR assay was conducted to detect dengue virus in NS1 positive samples. Phylogenetic tree based on E gene sequence of dengue virus were further analyzed. Results: During September-December 2014, an outbreak of dengue fever caused by dengue virus type 1 and 2 occurred in Guangxi, a total of 854 cases were reported without death, including 712 laboratory confirmed cases and 142 clinical diagnosed cases, in which 79.63% (680/854) occurred during 22 September-21 October 2014. All the cases had typical dengue fever symptoms. Most cases occurred in Nanning and Wuzhou, in which 83.61% (714/854) were in age group 15-59 years; 46.60% (398/854) were staff or people engaged in commercial service. A total 526 serum samples were tested for dengue virus serotype by RT-PCR assay. Among 414 positive samples, 345 were positive for dengue virus type 1 (DENV-1) and 69 were positive for dengue virus type 2 (DENV-2), no DENV-3 and DENV-4 were detected. The results of phylogenetic analysis of E gene sequence indicated that the sequences of 99.12%(113/114) of DENV-1 strains in Nanning in China shared 100.00% homology with the isolate (SG EHI D1/529Y13) from Singapore in 2013, which belonged to the genotype Ⅰ; All the DENV-2 isolates from Wuzhou shared 99.80% homology with the isolate (D14005) from Guangdong province, which belonged to genotype Cosmopolitan. Conclusions: The outbreak was caused by DENV-1 from Singapore and DENV-2 from Guangdong province in China. It is necessary to
Mitchell, E.; O'Mahony, M.; Watson, J. M.; Lynch, D.; Joseph, C.; Quigley, C.; Aston, R.; Constable, G. N.; Farrand, R. J.; Maxwell, S.; Hutchinson, D. N.; Craske, J.; Lee, J. V.
In 1988, there were two outbreaks of legionellosis in Bolton Health District. Altogether 37 cases of Legionnaires' disease and 23 cases of non-pneumonic legionellosis were identified. Twenty-five patients with Legionnaires' disease were associated with an engineering plant, 4 with Bolton town centre, and 8 with both the plant and town centre. Twenty-two people with non-pneumonic legionellosis were linked with the engineering plant and one with the plant and the town centre. A case-control study carried out among 37 employees with legionellosis and 109 control subjects at the plant showed that infection was associated with one of the 15 cooling towers on the site. Legionella pneumophila indistinguishable by serological and genetic typing methods was isolated from this cooling tower and from sputum samples from two patients. In the town centre, no one tower was linked with infection and L. pneumophila was not cultured from any of the nine towers identified. Control measures were implemented and to date there have been no further cases of legionellosis associated with Bolton Health District. PMID:2323354
Nawas, Zeena Y; Tong, Yun; Kollipara, Ramya; Peranteau, Andrew J; Woc-Colburn, Laila; Yan, Albert C; Lupi, Omar; Tyring, Stephen K
Given increased international travel, immigration, and climate change, bacterial and viral infections that were once unrecognized or uncommon are being seen more frequently in the Western Hemisphere. A delay in diagnosis and treatment of these diseases can lead to significant patient morbidity and mortality. However, the diagnosis and management of these infections is fraught with a lack of consistency because there is a dearth of dermatology literature on the cutaneous manifestations of these infections. We review the epidemiology, cutaneous manifestations, diagnosis, and management of these emerging bacterial and viral diseases.
Jeon, Sangho; Krasnow, Charles; Bhalsod, Gemini; Granke, Leah; Harlan, Blair; Hausbeck, Mary; Zhang, Wei
Previous research has been extensively focused on understanding the fate and transport of human microbial pathogens in soil and water environments. However, little is known about the transport of plant pathogens, although these pathogens are often found in irrigation waters and could cause severe crop damage and economical loss. Water mold pathogens including Phytophthora spp. and Pythium spp. are infective to a wide range of vegetable and floriculture crops, and they are primarily harbored in soils and disseminated through water flow. It is challenging to control these pathogens because they often quickly develop resistance to many fungicides. Therefore, this multi-scale study aimed to investigate physical removal of plant pathogens from water by filtration, thus reducing the pathogen exposure risks to crops. In column-scale experiments, we studied controlling factors on the transport and retention of Phytophthora capsici zoospores in saturated columns packed with iron oxide coated-sand and uncoated-sand under varying solution chemistry. Biflagellate zoospores were less retained than encysted zoospores, and lower solution pH and greater iron oxide content increased the retention of encysted zoospores. These results provided insights on environmental dispersal of Phytophthora zoospores in natural soils as well as on developing cost-effective engineered filtration systems for pathogen removal. Using small-scale greenhouse filtration systems, we further investigated the performance of varying filter media (i.e., granular sand, iron oxide coated ceramic porous media, and activated carbon) in mitigating disease outbreaks of Phytophthora and Pythium for greenhouse-grown squash and poinsettia, respectively, in comparison with fungicide treatment. For squash, filtration by iron oxide coated media was more effective in reducing the Phytophthora infection, comparing to sand filtration and fungicide application. For poinsettia, sand filtration performed better in controlling
In the summer of 2009, a new strain of Aeromonas hydrophila was implicated in severe disease outbreaks in farm-raised catfish in Alabama, Arkansas and Mississippi. These outbreaks mostly afflicted large fish and resulted in considerable losses in short periods. Given the rapid onset and biosecurity ...
Scott, Alister; Christie, Michael; Midmore, Peter
This paper assesses the impact of the 2001 foot-and-mouth disease outbreak in terms of its implications for the discipline of rural studies. In particular, it focuses on the position of agriculture in rural economy and society, the standing of the government after its management of the outbreak, and the performance of the new devolved regional…
Recreational water–associated disease outbreaks result from exposure to infectious pathogens or chemical agents in treated recreational–water (e.g., pools and hot tubs or spas) or untreated recreational¬–water (e.g., lakes and oceans) venues. Outbreaks occurring during 2009–2010 ...
Kline, Jennifer; Monahan, Caitlin; Vierk, Katherine
The proportion of US food that is imported is increasing; most seafood and half of fruits are imported. We identified a small but increasing number of foodborne disease outbreaks associated with imported foods, most commonly fish and produce. New outbreak investigation tools and federal regulatory authority are key to maintaining food safety. PMID:28221117
Amemura-Maekawa, Junko; Ohya, Hitomi; Furukawa, Ichiro; Suzuki, Miyuki; Masaoka, Tomoka; Aikawa, Kastuhiro; Hibi, Kazumi; Morita, Masatomo; Lee, Ken-ichi; Ohnishi, Makoto; Kura, Fumiaki
In Japan, hot springs and public baths are the major sources of legionellosis. In 2015, an outbreak of Legionnaires’ disease occurred among 7 patients who had visited a spa house. Laboratory investigation indicated that L. pneumophila serogroup 1 and 13 strains caused the outbreak and that these strains were genetically related. PMID:28098535
Forde, Taya; Pruvot, Mathieu; De Buck, Jeroen; Orsel, Karin
Following an outbreak of Johne’s disease on an elk farm in northern Alberta, Canada, fecal culture, fecal polymerase chain reaction (PCR), and serum enzyme-linked immunosorbent assay (ELISA) tests were performed on individual animals. The magnitude of the outbreak is described and the challenges associated with poor test agreement, as well as herd management options, are discussed. PMID:25969580
Maynard, J. A.; Anthony, K. R. N.; Harvell, C. D.; Burgman, M. A.; Beeden, R.; Sweatman, H.; Heron, S. F.; Lamb, J. B.; Willis, B. L.
Links between anomalously high sea temperatures and outbreaks of coral diseases known as White Syndromes (WS) represent a threat to Indo-Pacific reefs that is expected to escalate in a changing climate. Further advances in understanding disease aetiologies, determining the relative importance of potential risk factors for outbreaks and in trialing management actions are hampered by not knowing where or when outbreaks will occur. Here, we develop a tool to target research and monitoring of WS outbreaks in the Great Barrier Reef (GBR). The tool is based on an empirical regression model and takes the form of user-friendly interactive ~1.5-km resolution maps. The maps denote locations where long-term monitoring suggests that coral cover exceeds 26% and summer temperature stress (measured by a temperature metric termed the mean positive summer anomaly) is equal to or exceeds that experienced at sites in 2002 where the only severe WS outbreaks documented on the GBR to date were observed. No WS outbreaks were subsequently documented at 45 routinely surveyed sites from 2003 to 2008, and model hindcasts for this period indicate that outbreak likelihood was never high. In 2009, the model indicated that outbreak likelihood was high at north-central GBR sites. The results of the regression model and targeted surveys in 2009 revealed that the threshold host density for an outbreak decreases as thermal stress increases, suggesting that bleaching could be a more important precursor to WS outbreaks than previously anticipated, given that bleaching was severe at outbreak sites in 2002 but not at any of the surveyed sites in 2009. The iterative approach used here has led to an improved understanding of disease causation, will facilitate management responses and can be applied to other coral diseases and/or other regions.
Kyriakis, C S; Billinis, C; Papadopoulos, E; Vasileiou, N G C; Athanasiou, L V; Fthenakis, G C
Bluetongue is an arthropod-borne viral disease of ruminants, especially of sheep, caused by Bluetongue virus, which belongs to the genus Orbivirus of the family Reoviridae and is classified into 26 antigenically distinct serotypes. Once thought to be restricted in Africa and parts of the Middle East, bluetongue has now become a concern in sheep-rearing countries around the world. In the past 10 years, severe outbreaks have occurred in Europe with important economic consequences; of these, the 2006-20008 outbreak in Europe was caused by a serotype 8 strain and the 2014 outbreak in Greece and the other countries of south-east Europe was caused by a serotype 4 strain, suggested to be a reassortant strain with genome segments from lineages of serotype 1, 2 and 4. Immunisation campaigns can be implemented for successful control and limiting of the disease. Nevertheless, in both of the above outbreaks, late application of vaccinations led to a wide spread of the disease, which subsequently resulted in significant losses in livestock in the affected regions. In view of that, standardisation of control measures in the future will be beneficial for efficiently limiting outbreaks of the disease.
Ahearn, Donald G; Doyle Stulting, R
Fungi rarely cause disease outbreaks associated with use of microbe-contaminated drugs. These rare episodes typically involve a restricted spectrum of common environmental species with relatively low virulence, rather than classical pathogens. Review of data involving over-the-counter contact lens solutions and prescription drug-related recalls revealed six episodes during the past decade with significant adverse health and financial impact (including loss of vision and death). Contaminations involved fungi mostly identified with the genera Aspergillus, Exserohilum, Fusarium, Paecilomyces, and Rhizopus. These organisms are noted for their capacity to produce resistant morphotypes (chlamydoconidia, ascospores) under various adverse conditions, generally with temperature survival/tolerances markedly in excess of maximal growth temperatures. High constituent levels of melanin, trehalose and heat-shock proteins facilitate differential survival of morphotypes following exposures to toxic chemicals and temperatures above 80 °C. Adverse environmental factors that induce resistant morphotypes are suggested to occur more readily in situ than during in vitro testing. Rare unexplained, sporadic drug contamination episodes with select thermotolerant fungi may relate, in part, to resistant dormant stages.
Kapil, Sanjay; Yeary, Teresa; Evermann, James F
The increased popularity and population of New World camelids in the United States requires the development of a broader base of knowledge of the health and disease parameters for these animals by the veterinary livestock practitioner. Although our knowledge regarding infectious diseases of camelids has increased greatly over the past decade, the practice of camelid medicine is a relatively new field in North America, so it is important to seek out seasoned colleagues and diagnostic laboratories that are involved in camelid health treatment and diagnosis.
This report demonstrates how data from the Waterborne Disease Outbreak Surveillance System (WBDOSS) can be used to estimate disease burden and presents results using 30 years of data. This systematic analysis does not attempt to provide an estimate of the actual incidence and b...
Rooney, Roisin M.; Bartram, Jamie K.; Cramer, Elaine H.; Mantha, Stacey; Nichols, Gordon; Suraj, Rohini; Todd, Ewen C. D.
OBJECTIVE: The organization of water supply to and on ships differs considerably from that of water supply on land. Risks of contamination can arise from source water at the port or during loading, storage, or distribution on the ship. The purpose of this article is to review documented outbreaks of waterborne diseases associated with passenger, cargo, fishing, and naval ships to identify contributing factors so that similar outbreaks can be prevented in the future. METHODS: The authors reviewed 21 reported outbreaks of waterborne diseases associated with ships. For each outbreak, data on pathogens/toxins, type of ship, factors contributing to outbreaks, mortality and morbidity, and remedial action are presented. RESULTS: The findings of this review show that the majority of reported outbreaks were associated with passenger ships and that more than 6,400 people were affected. Waterborne outbreaks due to Enterotoxigenic Escherichia coli, noroviruses, Salmonella spp, Shigella sp, Cryptosporidium sp, and Giardia lamblia occurred on ships. Enterotoxigenic E. coli was the pathogen most frequently associated with outbreaks. One outbreak of chemical water poisoning also occurred on a ship. Risk factors included contaminated port water, inadequate treatment, improper loading techniques, poor design and maintenance of storage tanks, ingress of contamination during repair and maintenance, cross-connections, back siphonage, and insufficient residual disinfectant. CONCLUSIONS: Waterborne disease outbreaks on ships can be prevented. The factors contributing to outbreaks emphasize the need for hygienic handling of water along the supply chain from source to consumption. A comprehensive approach to water safety on ships is essential. This may be achieved by the adoption of Water Safety Plans that cover design, construction, operation, and routine inspection and maintenance. PMID:15219801
Crim, Marcus J; Riley, Lela K
Naturally occurring viral infections have the potential to introduce confounding variability that leads to invalid and misinterpreted data. Whereas the viral diseases of research rodents are well characterized and closely monitored, no naturally occurring viral infections have been characterized for the laboratory zebrafish (Danio rerio), an increasingly important biomedical research model. Despite the ignorance about naturally occurring zebrafish viruses, zebrafish models are rapidly expanding in areas of biomedical research where the confounding effects of unknown infectious agents present a serious concern. In addition, many zebrafish research colonies remain linked to the ornamental (pet) zebrafish trade, which can contribute to the introduction of new pathogens into research colonies, whereas mice used for research are purpose bred, with no introduction of new mice from the pet industry. Identification, characterization, and monitoring of naturally occurring viruses in zebrafish are crucial to the improvement of zebrafish health, the reduction of unwanted variability, and the continued development of the zebrafish as a model organism. This article addresses the importance of identifying and characterizing the viral diseases of zebrafish as the scope of zebrafish models expands into new research areas and also briefly addresses zebrafish susceptibility to experimental viral infection and the utility of the zebrafish as an infection and immunology model.
Crim, Marcus J.; Riley, Lela K.
Naturally occurring viral infections have the potential to introduce confounding variability that leads to invalid and misinterpreted data. Whereas the viral diseases of research rodents are well characterized and closely monitored, no naturally occurring viral infections have been characterized for the laboratory zebrafish (Danio rerio), an increasingly important biomedical research model. Despite the ignorance about naturally occurring zebrafish viruses, zebrafish models are rapidly expanding in areas of biomedical research where the confounding effects of unknown infectious agents present a serious concern. In addition, many zebrafish research colonies remain linked to the ornamental (pet) zebrafish trade, which can contribute to the introduction of new pathogens into research colonies, whereas mice used for research are purpose bred, with no introduction of new mice from the pet industry. Identification, characterization, and monitoring of naturally occurring viruses in zebrafish are crucial to the improvement of zebrafish health, the reduction of unwanted variability, and the continued development of the zebrafish as a model organism. This article addresses the importance of identifying and characterizing the viral diseases of zebrafish as the scope of zebrafish models expands into new research areas and also briefly addresses zebrafish susceptibility to experimental viral infection and the utility of the zebrafish as an infection and immunology model. PMID:23382345
Beer, Karlyn D; Gargano, Julia W; Roberts, Virginia A; Hill, Vincent R; Garrison, Laurel E; Kutty, Preeta K; Hilborn, Elizabeth D; Wade, Timothy J; Fullerton, Kathleen E; Yoder, Jonathan S
Advances in water management and sanitation have substantially reduced waterborne disease in the United States, although outbreaks continue to occur. Public health agencies in the U.S. states and territories* report information on waterborne disease outbreaks to the CDC Waterborne Disease and Outbreak Surveillance System (http://www.cdc.gov/healthywater/surveillance/index.html). For 2011-2012, 32 drinking water-associated outbreaks were reported, accounting for at least 431 cases of illness, 102 hospitalizations, and 14 deaths. Legionella was responsible for 66% of outbreaks and 26% of illnesses, and viruses and non-Legionella bacteria together accounted for 16% of outbreaks and 53% of illnesses. The two most commonly identified deficiencies† leading to drinking water-associated outbreaks were Legionella in building plumbing§ systems (66%) and untreated groundwater (13%). Continued vigilance by public health, regulatory, and industry professionals to identify and correct deficiencies associated with building plumbing systems and groundwater systems could prevent most reported outbreaks and illnesses associated with drinking water systems.
Blanchard, Patricia C; Ridpath, Julia F; Walker, Jennifer B; Hietala, Sharon K
Bovine viral diarrhea virus 1 (BVDV-1) subtype b was isolated from premature Holstein calves from a dairy herd that experienced an outbreak of premature births, late-term abortions, brachygnathism, growth retardation, malformations of the brain and cranium, and rare extracranial skeletal malformations in calves born to first-calf heifers. Experimental inoculation of 3 colostrum-deprived calves aged 2-4 months old with this BVDV isolate resulted in thrombocytopenia, lymphopenia, and leukopenia. Outbreaks of brachygnathism are rarely associated with BVDV, and thrombocytopenia is rarely associated with BVDV-1 strains.
Bankiewicz, Krystof; Cunningham, Janet
Methods of delivering viral vectors, particularly recombinant adeno-associated virus (rAAV) virions, to the central nervous system (CNS) using convection enhanced delivery (CED) are provided. The rAAV virions include a nucleic acid sequence encoding a therapeutic polypeptide. The methods can be used for treating CNS disorders such as for treating Parkinson's Disease.
Kirrage, David; Hunt, David; Ibbotson, Sue; McCloskey, Brian; Reynolds, Gary; Hawker, Jeremy; Smith, Gillian E; Olowokure, Babatunde
The outbreak of Legionnaires' disease that occurred in Hereford, West Midlands UK in 2003 was the single largest outbreak of Legionnaires' in Hereford and one of the first to challenge the newly formed Health Protection Agency. This was, de facto a 'public health incident' requiring not only the investigation and management of a community outbreak of infectious disease, but also one that had to take into account other issues including: uncertainty regarding roles and responsibilities, political considerations and communication needs including sustained media attention. The incident also demonstrated the 'added value' of an integrated health protection response. The practical lessons learned from outbreaks are rarely described, particularly operational aspects. This paper summarises the outbreak, outlines specific elements of the response and identifies some of the key learning points for the new Agency and its partners. A number of these lessons have a generic applicability to the handling of public health incidents.
Roep, Bart O
Viral infections have been associated with the development of several neurological and neuroendocrine autoimmune diseases. Structural similarities between environmental proteins and self-proteins have long been proposed to be targets for immune cross reactivity associated with initiation of autoimmune diseases. This mechanism called molecular mimicry has also been put forward for immune mediated neurological diseases associated with viral infection. Although many potential candidates for cross reactivity have been put forward, only few have been substantiated on the molecular level. For the definition of cellular immune cross-reactivity, it proved critical to appreciate that recognition patterns of T-cells are not linear. Subsequent microarray studies unequivocally demonstrated functional mimicry of seemingly disparate amino acid sequences. This review summarises the present evidence for molecular mimicry in neurological autoimmune diseases and virus
Fernández-Sirera, Laura; Riba, Landry; Cabezón, Oscar; Rosell, Rosa; Serrano, Emmanuel; Lavín, Santiago; Marco, Ignasi
The Principality of Andorra is surrounded by areas in which Pyrenean chamois (Rupicapra pyrenaica pyrenaica) populations were severely affected by infection with border disease virus (BDV) which caused disease outbreaks between 2001 and 2009. Nevertheless, the Andorran chamois populations were not affected during this period. In light of the severe impact of BDV on several of the neighboring Pyrenean chamois populations, we monitored local Andorran populations in an effort to detect pestivirus antibodies and BDV in wild ungulates. In addition, an episode of mortality between 2009 and 2010 in chamois was investigated. We analyzed samples (spleen or serum) from 175 Pyrenean chamois, 284 European mouflon (Ovis orientalis musimon), 13 roe deer (Capreolus capreolus capreolus), and five wild boars (Sus scrofa castilianus). With the exception of three dead chamois found between 2009 and 2010, all samples came from healthy animals hunted during the hunting season. A commercial blocking enzyme-linked immunosorbent assay (ELISA) was used to test sera for antibodies against pestivirus. Positive sera were tested with a comparative virus neutralization test (VNT) using three BDV strains and a bovine viral diarrhea virus strain. Reverse-transcription-polymerase chain reaction (RT-PCR) was performed on all sera and spleen homogenates. Antibodies against pestivirus were detected by ELISA in four of the 69 chamois (5%; 95% CI= 1.29-13.11). The VNT confirmed three of these chamois were infected with a BDV. Viral RNA was detected by RT-PCR in three chamois-one apparently healthy animal hunted in 2009 and two dead animals. Viral sequences showed that the three chamois were infected with a BDV-4, the same genotype that was involved in previous episodes of mortality in the Pyrenees. Although Pyrenean chamois from Andorra had had little contact with the pestiviruses until 2009, in this year BDV was associated with a severe disease outbreak.
Godsey, Marvin S.; Burkhalter, Kristen; Young, Ginger; Delorey, Mark; Smith, Kirk; Townsend, John; Levy, Craig; Mutebi, John-Paul
Entomologic investigations were conducted during an intense outbreak of West Nile virus (WNV) disease in Maricopa County, Arizona during July 31–August 9, 2010. The investigations compared the East Valley outbreak area, and a demographically similar control area in northwestern metropolitan Phoenix where no human cases were reported. Five mosquito species were identified in each area, and species composition was similar in both areas. Significantly more Culex quinquefasciatus females were collected by gravid traps at Outbreak sites (22.2 per trap night) than at control sites (8.9 per trap night), indicating higher Cx. quinquefasciatus abundance in the outbreak area. Twenty-eight WNV TaqMan reverse transcription-polymerase chain reaction–positive mosquito pools were identified, including 24 of Cx. quinquefasciatus, 3 of Psorophora columbiae, and 1 of Culex sp. However, Cx. quinquefasciatus WNV infection rates did not differ between outbreak and control sites. At outbreak sites, 30 of 39 engorged Cx. quinquefasciatus had fed on birds, 8 of 39 on humans, and 1 of 39 on a lizard. At control sites, 20 of 20 identified blood meals were from birds. Data suggest that Cx. quinquefasciatus was the primary enzootic and epidemic vector of this outbreak. The most important parameters in the outbreak were vector abundance and blood meal analysis, which suggested more frequent contact between Cx. quinquefasciatus and human hosts in the outbreak area compared with the control area. PMID:23109372
Rowe, Regina K; Gill, Michelle A
Respiratory viruses and allergens synergistically contribute to disease pathogenesis in asthma. Potential mechanisms underlying this clinically relevant association are the subject of intense investigation. This review summarizes current knowledge and recent advances in this area, with an emphasis on potential mechanisms involving immunoglobulin E, type I interferon antiviral responses, epithelial factors, and the role of dendritic cells and other antigen-presenting cells in linking viral and allergic inflammatory responses relevant to asthmatic disease.
Long, Jason; Wright, Edward; Molesti, Eleonora; Temperton, Nigel; Barclay, Wendy
Emerging viral diseases pose a threat to the global population as intervention strategies are mainly limited to basic containment due to the lack of efficacious and approved vaccines and antiviral drugs. The former was the only available intervention when the current unprecedented Ebolavirus (EBOV) outbreak in West Africa began. Prior to this, the development of EBOV vaccines and anti-viral therapies required time and resources that were not available. Therefore, focus has turned to re-purposing of existing, licenced medicines that may limit the morbidity and mortality rates of EBOV and could be used immediately. Here we test three such medicines and measure their ability to inhibit pseudotype viruses (PVs) of two EBOV species, Marburg virus (MARV) and avian influenza H5 (FLU-H5). We confirm the ability of chloroquine (CQ) to inhibit viral entry in a pH specific manner. The commonly used proton pump inhibitors, Omeprazole and Esomeprazole were also able to inhibit entry of all PVs tested but at higher drug concentrations than may be achieved in vivo. We propose CQ as a priority candidate to consider for treatment of EBOV. PMID:26069727
Eastwood, Daniel; Green, Julian; Grogan, Helen; Burton, Kerry
The symptoms of viral infections of fungi range from cryptic to severe, but there is little knowledge of the factors involved in this transition of fungal/viral interactions. Brown cap mushroom disease of the cultivated Agaricus bisporus is economically important and represents a model system to describe this transition. Differentially expressed transcript fragments between mushrooms showing the symptoms of brown cap mushroom disease and control white noninfected mushrooms have been identified and sequenced. Ten of these RNA fragments have been found to be upregulated over 1,000-fold between diseased and nondiseased tissue but are absent from the Agaricus bisporus genome sequence and hybridize to double-stranded RNAs extracted from diseased tissue. We hypothesize that these transcript fragments are viral and represent components of the disease-causing agent, a bipartite virus with similarities to the family Partitiviridae. The virus fragments were found at two distinct levels within infected mushrooms, at raised levels in infected, nonsymptomatic, white mushrooms and at much greater levels (3,500 to 87,000 times greater) in infected mushrooms exhibiting brown coloration. In addition, differential screening revealed 9 upregulated and 32 downregulated host Agaricus bisporus transcripts. Chromametric analysis was able to distinguish color differences between noninfected white mushrooms and white infected mushrooms at an early stage of mushroom growth. This method may be the basis for an "on-farm" disease detection assay.
Shultz, James M.; Espinel, Zelde; Espinola, Maria; Rechkemmer, Andreas
ABSTRACT The 2013–2016 West Africa Ebola virus disease epidemic was notable for its scope, scale, and complexity. This briefing presents a series of distinguishing epidemiological features that set this outbreak apart. Compared to one concurrent and 23 previous outbreaks of the disease over 40 years, this was the only occurrence of Ebola virus disease involving multiple nations and qualifying as a pandemic. Across multiple measures of magnitude, the 2013–2016 outbreak was accurately described using superlatives: largest and deadliest in terms of numbers of cases and fatalities; longest in duration; and most widely dispersed geographically, with outbreak-associated cases occurring in 10 nations. In contrast, the case-fatality rate was much lower for the 2013–2016 outbreak compared to the other 24 outbreaks. A population of particular interest for ongoing monitoring and public health surveillance is comprised of more than 17,000 “survivors,” Ebola patients who successfully recovered from their illness. The daunting challenges posed by this outbreak were met by an intensive international public health response. The near-exponential rate of increase of incident Ebola cases during mid-2014 was successfully slowed, reversed, and finally halted through the application of multiple disease containment and intervention strategies. PMID:28229017
Social media introduce pivotal changes to communication between individuals, organizations and communities. A clear example of the power of social media is the spread of the revolutionary outbreaks in the Arabic countries during 2011, where people used Facebook, YouTube and Skype to communicate, organise meetings and protest actions. Here I report how Doctor-Activists use these social media as an alarm system for 'war disease' outbreaks in the Syrian Spring. Social media are used as an alarm system to attract the attention of international organizations, which should assume their responsibilities and play their part in controlling the outbreak of such war diseases.
Zhao, Yujiao; Li, Lihua; Ma, Dehong; Luo, Jia; Ma, Zhiqiang; Wang, Xiaodan; Pan, Yue; Chen, Junying; Xi, Juemin; Yang, Jiajia; Qiu, Lijuan; Bai, Chunhai; Jiang, Liming; Shan, Xiyun; Sun, Qiangming
A total of 1067 serum samples were collected from febrile patients in Xishuangbanna, Yunnan, 2015. Of these, 852 cases were confirmed to be dengue NS1-positive. 76 structural protein genes were sequenced through RT-PCR based on the viral RNAs extracted from serum samples. Phylogenetic analysis revealed that all strains were classified as cosmopolitan genotype of DENV-2. After comparing with the DENV-2SS, 173 base substitutions were found in 76 sequences, resulting in 43 nonsynonymous mutations, of which 22 mutations existed among all samples. According to secondary structure prediction, 8 new possible nucelotide/protein binding sites were found and another 4 sites were lost among the 775 amino acids of DENV structural proteins as compared with DENV-2SS. Meanwhile, 6 distinct amino acid changes were found in the helix and strand regions, and the distribution of the exposed and buried regions was slightly altered. The results indicated that the epidemic dengue strains of Xishuangbanna in 2015 are most similar to the Indian strain in 2001 and the Sri Lankan strain in 2004. Moreover, it also show a very strong similarity to the epidemic strains of Fujian province in 1999 and 2010, which show that there is an internal recycling epidemic trend of DENV in China. PMID:27681163
Despite advances in water management and sanitation, waterborne disease outbreaks continue to occur in the United States. CDC collects data on waterborne disease outbreaks submitted from all states and territories through the Waterborne Disease and Outbreak Surveillance System. During 2009-2010, the most recent years for which finalized data are available, 33 drinking water-associated outbreaks were reported, comprising 1,040 cases of illness, 85 hospitalizations, and nine deaths. Legionella accounted for 58% of outbreaks and 7% of illnesses, and Campylobacter accounted for 12% of outbreaks and 78% of illnesses. The most commonly identified outbreak deficiencies in drinking water-associated outbreaks were Legionella in plumbing systems (57.6%), untreated ground water (24.2%), and distribution system deficiencies (12.1%), suggesting that efforts to identify and correct these deficiencies could prevent many outbreaks and illnesses associated with drinking water. In addition to the drinking water outbreaks, 12 outbreaks associated with other nonrecreational water were reported, comprising 234 cases of illness, 51 hospitalizations, and six deaths. Legionella accounted for 58% of these outbreaks, 42% of illnesses, 96% of hospitalizations, and all deaths. Public health, regulatory, and industry professionals can use this information to target prevention efforts against pathogens, infrastructure problems, and water sources associated with waterborne disease outbreaks.
Pourbohloul, Babak; Meyers, Lauren A.; Newman, Mark E. J.; Skowronski, Danuta M.
A large class of infectious diseases spread through direct person-to-person contact. Traditional ``compartmental'' modeling in epidemiology assumes that in population groups every individual has an equal chance of spreading the disease to every other. The patterns of these contacts, however, tend to be highly heterogeneous. Explicit models of the patterns of contact among individuals in a community, contact network models, underlie a powerful approach to predicting and controlling the spread of such infectious disease and provide detailed and valuable insight into the fate and control of an outbreak. We use contact network epidemiology to predict the impact of various control policies for both a mildly contagious disease such as SARS and a more highly contagious disease such as smallpox. We demonstrate how integrating these tools into public health decision-making should facilitate more rational strategies for managing newly emerging diseases, bioterrorism and pandemic influenza in situations where empirical data are not yet available to guide decision making.
Beeden, Roger; Maynard, Jeffrey A; Marshall, Paul A; Heron, Scott F; Willis, Bette L
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.
Beeden, Roger; Maynard, Jeffrey A.; Marshall, Paul A.; Heron, Scott F.; Willis, Bette L.
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.
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
Spengler, Jessica R.; Ervin, Elizabeth D.; Towner, Jonathan S.; Rollin, Pierre E.
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
Spengler, Jessica R.; Ervin, Elizabeth D.; Towner, Jonathan S.; Rollin, Pierre E.; Nichol, Stuart T.
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 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.
Larson, Robert L
Bovine viral diarrhea virus (BVDv) is associated with bovine respiratory disease complex and other diseases of feedlot cattle. Although occasionally a primary pathogen, BVDv's impact on cattle health is through the immunosuppressive effects of the virus and its synergism with other pathogens. The simple presence or absence of BVDv does not result in consistent health outcomes because BVDv is only one of many risk factors that contribute to disease syndromes. Current interventions have limitations and the optimum strategy for their uses to limit the health, production, and economic costs associated with BVDv have to be carefully considered for optimum cost-effectiveness.
Boxrud, David; Monson, Timothy; Stiles, Tracy; Besser, John
In recent years, there have been several high-profile nationwide foodborne outbreaks due to enteric organisms in food products, including Salmonella Typhimurium in peanut products, Salmonella Saintpaul in peppers, and Escherichia coli O157:H7 in spinach. PulseNet, the national molecular subtyping network for foodborne disease surveillance, played a key role in detecting each of these outbreaks. PulseNet laboratories use bacterial subtyping methods to rapidly detect clusters of foodborne disease, which are often the first indication that an outbreak is occurring. Rapid outbreak detection reduces ongoing transmission through product recalls, restaurant closures, and other mechanisms. By greatly increasing the sensitivity of outbreak detection, PulseNet allows us to identify and correct problems with our food production and distribution systems that would not otherwise have come to our attention. Annually, millions of potentially preventable cases of foodborne illness result in billions of dollars in lost productivity and health-care expenses. We describe the critical role PulseNet laboratories play in the detection of foodborne outbreaks and discuss current challenges and potential improvements for PulseNet laboratories to more rapidly identify future foodborne outbreaks.
Smerdon, W J; Adak, G K; O'Brien, S J; Gillespie, I A; Reacher, M
Between 1992 and 1999, 1,426 foodborne general outbreaks of infectious intestinal disease (IID) were reported to the Public Health Laboratory Service (PHLS) Communicable Disease Surveillance Centre (CDSC). Sixteen percent were linked with the consumption of red meat. Over 5,000 people were affected, with 186 hospital admissions and nine deaths. Beef (34%) and pig meat (32%) were the most frequently implicated meat types, with lamb implicated in 11% of outbreaks. The organisms most frequently reported were Clostridium perfringens (43.4%) and salmonellas (34.3%). During the summer, outbreaks were mainly of Salmonella spp. and attributed to the consumption of pig meat. In December, outbreaks of C. perfringens linked with beef predominated. Most outbreaks occurred as a result of food cooked on commercial catering premises (46%). The highlight of this surveillance period is a fall in the number of outbreaks linked with foods containing red meat. This corresponds with a steady decline in red meat consumption over the last two decades, as well as a transient though marked decline in the purchase and consumption of red meat in the UK during the BSE crisis in the early to mid 1990s. As cited in the Pennington Report, further reducing the morbidity and mortality from red meat outbreaks means targeting meat production at various points along the food chain from abattoir and butchering, to cooking and holding of cooked food, especially on commercial catering premises.
Culley, Fiona J; Pennycook, Alasdair M J; Tregoning, John S; Dodd, Jonathan S; Walzl, Gerhard; Wells, Timothy N; Hussell, Tracy; Openshaw, Peter J M
CCL5/RANTES is a key proinflammatory chemokine produced by virus-infected epithelial cells and present in respiratory secretions of asthmatics. To examine the role of CCL5 in viral lung disease, we measured its production during primary respiratory syncytial virus (RSV) infection and during secondary infection after sensitizing vaccination that induces Th2-mediated eosinophilia. A first peak of CCL5 mRNA and protein production was seen at 18 to 24 h of RSV infection, before significant lymphocyte recruitment occurred. Treatment in vivo with Met-RANTES (a competitive chemokine receptor blocker) throughout primary infection decreased CD4+ and CD8+ cell recruitment and increased viral replication. In RSV-infected, sensitized mice with eosinophilic disease, CCL5 production was further augmented; Met-RANTES treatment again reduced inflammatory cell recruitment and local cytokine production. A second wave of CCL5 production occurred on day 7, attributable to newly recruited T cells. Paradoxically, mice treated with Met-RANTES during primary infection demonstrated increased cellular infiltration during reinfection. We therefore show that RSV induces CCL5 production in the lung and this causes the recruitment of RSV-specific cells, including those making additional CCL5. If this action is blocked with Met-RANTES, inflammation decreases and viral clearance is delayed. However, the exact effects of chemokine modulation depend critically on time of administration, a factor that may potentially complicate the use of chemokine blockers in inflammatory diseases.
Eiguer, T; Caffer, M I; Fronchkowsky, G B
This paper reports on the outbreaks of food-borne-diseases due to Salmonella Enteritidis which occurred in Argentina between 1986 and 1988. In 39 registered episodes 210 strains were isolated from human feces (28 outbreaks) and 59 from food (23 outbreaks). More than 2,500 people in different provinces were affected, the chief characteristics of the clinical picture being the gravity of the symptoms (high temperature, vomiting, diarrhea and severe dehydration). The main source of infection was related to raw eggs, eaten in the form of home-made mayonnaise. It is considered necessary to carry out an effective control of poultry products, as well as a permanent surveillance of salmonellosis.
Morand, Serge; Jittapalapong, Sathaporn; Suputtamongkol, Yupin; Abdullah, Mohd Tajuddin; Huan, Tan Boon
Despite increasing control measures, numerous parasitic and infectious diseases are emerging, re-emerging or causing recurrent outbreaks particularly in Asia and the Pacific region, a hot spot of both infectious disease emergence and biodiversity at risk. We investigate how biodiversity affects the distribution of infectious diseases and their outbreaks in this region, taking into account socio-economics (population size, GDP, public health expenditure), geography (latitude and nation size), climate (precipitation, temperature) and biodiversity (bird and mammal species richness, forest cover, mammal and bird species at threat). We show, among countries, that the overall richness of infectious diseases is positively correlated with the richness of birds and mammals, but the number of zoonotic disease outbreaks is positively correlated with the number of threatened mammal and bird species and the number of vector-borne disease outbreaks is negatively correlated with forest cover. These results suggest that, among countries, biodiversity is a source of pathogens, but also that the loss of biodiversity or its regulation, as measured by forest cover or threatened species, seems to be associated with an increase in zoonotic and vector-borne disease outbreaks. PMID:24587201
Ghosh, Saurav; Chakraborty, Prithwish; Nsoesie, Elaine O.; Cohn, Emily; Mekaru, Sumiko R.; Brownstein, John S.; Ramakrishnan, Naren
In retrospective assessments, internet news reports have been shown to capture early reports of unknown infectious disease transmission prior to official laboratory confirmation. In general, media interest and reporting peaks and wanes during the course of an outbreak. In this study, we quantify the extent to which media interest during infectious disease outbreaks is indicative of trends of reported incidence. We introduce an approach that uses supervised temporal topic models to transform large corpora of news articles into temporal topic trends. The key advantages of this approach include: applicability to a wide range of diseases and ability to capture disease dynamics, including seasonality, abrupt peaks and troughs. We evaluated the method using data from multiple infectious disease outbreaks reported in the United States of America (U.S.), China, and India. We demonstrate that temporal topic trends extracted from disease-related news reports successfully capture the dynamics of multiple outbreaks such as whooping cough in U.S. (2012), dengue outbreaks in India (2013) and China (2014). Our observations also suggest that, when news coverage is uniform, efficient modeling of temporal topic trends using time-series regression techniques can estimate disease case counts with increased precision before official reports by health organizations.
Ghosh, Saurav; Chakraborty, Prithwish; Nsoesie, Elaine O.; Cohn, Emily; Mekaru, Sumiko R.; Brownstein, John S.; Ramakrishnan, Naren
In retrospective assessments, internet news reports have been shown to capture early reports of unknown infectious disease transmission prior to official laboratory confirmation. In general, media interest and reporting peaks and wanes during the course of an outbreak. In this study, we quantify the extent to which media interest during infectious disease outbreaks is indicative of trends of reported incidence. We introduce an approach that uses supervised temporal topic models to transform large corpora of news articles into temporal topic trends. The key advantages of this approach include: applicability to a wide range of diseases and ability to capture disease dynamics, including seasonality, abrupt peaks and troughs. We evaluated the method using data from multiple infectious disease outbreaks reported in the United States of America (U.S.), China, and India. We demonstrate that temporal topic trends extracted from disease-related news reports successfully capture the dynamics of multiple outbreaks such as whooping cough in U.S. (2012), dengue outbreaks in India (2013) and China (2014). Our observations also suggest that, when news coverage is uniform, efficient modeling of temporal topic trends using time-series regression techniques can estimate disease case counts with increased precision before official reports by health organizations. PMID:28102319
Amend, Donald F.
Three viral diseases of salmonids are of worldwide concern: infectious pancreatic necrosis (IPN) viral hemorrhagic septicemia (VHS), and infectious hematopoietic necrosis (IHN). Six principal approaches are being used to prevent or control these diseases: 1) preventing contact o the pathogen with the host, 2) environmental manipulation, 3) immunization, 4) chemotherapy, 5 selective breeding for disease resistance, and 6) reducing stress conditions which augment disease conditions. Preventing the introduction of a pathogen into a new stock of fish has been accomplished mainly by implementing stringent laws to prevent transport of infected fish into uninfected areas. Stocks of fish already infected are sometimes destroyed, and the hatchery is disinfected and restocked with fish free of specific pathogens. Environmental manipulation (elevated water temperature) has been successfully used to control IHN. Chemotherapeutics such as povidone-iodine for IPN and benzipyrene for IHN show promise of controlling mortalities; however, the practicality of using these drugs to eliminate the carrier fish has not been evaluated. Salmonids are capable of developing immune responses to viruses; however, development of effective vaccines, selective breeding for disease resistance, and identification of stress conditions which augment disease are still in the experimental phase.
Haigh, J C; Mackintosh, C; Griffin, F
The most important viral disease of farmed deer and bison is malignant catarrhal fever. The other herpesviruses which have been isolated from these species are briefly described. Other viral agents that are recognised in these animals, including adenovirus, parapox, foot and mouth disease, bluetongue, epizootic haemorrhagic disease, bovine virus diarrhoea, rotavirus and coronavirus, are also discussed. Ectoparasites of importance in this group in various parts of the world include a variety of ticks, as well as lice, keds, Oestridae, mange mites and fire ants. Helminth parasites include liver flukes (Fascioloides and Fasciola), gastrointestinal nematodes of the family Trichostrongylidae, pulmonary lungworms of the genus Dictyocaulus and extra-pulmonary lungworms of the family Protostrongylidae. Chronic wasting disease is principally important in North America, where the disease occurs in wild cervids in a limited area and has been reported in farmed deer in a small number of states in the United States of America and one province in Canada. These diseases are summarised in terms of their classification, epidemiology, clinical signs, pathology, diagnosis, treatment and control.
Zmak, Ljiljana; Obrovac, Mihaela; Lovric, Zvjezdana; Jankovic Makek, Mateja; Katalinic Jankovic, Vera
As tuberculosis incidence decreases, the possibility of overlooking the disease increases, especially in vulnerable populations. We describe here a major tuberculosis outbreak among mentally ill patients in Croatia, focusing on 1 regional hospital where most patients were hospitalized. The outbreak emphasizes the vulnerability of mentally ill patients to tuberculosis infection and the complexity of infection control measures in psychiatric institutions. The awareness of tuberculosis in these settings should be maintained to interrupt prolonged exposure and avoid unnecessary infection.
Mohammed, Ibrahim; Saidu, Yauba
The West African sub-continent is currently experiencing its first, and ironically, the largest and longest Ebola viral diseases (EVD) outbreak ever documented in modern medical history. The current outbreak is significant in several ways, including longevity, magnitude of morbidity and mortality, occurrence outside the traditional niches, rapid spread and potential of becoming a global health tragedy. The authors provided explicit insights into the current and historical background, drivers of the epidemic, societal impacts, status of vaccines and drugs development and proffered recommendations to halt and prevent future occurrences. The authors reviewed mainly five databases and a hand search of key relevant literature. We reviewed 51 articles that were relevant up until the 18th of August 2014. The authors supplemented the search with reference list of relevant articles and grey literature as well as relevant Internet websites. Article searches were limited to those published either in English or French. There are strong indications that the EVD may have been triggered by increased human activities and encroachment into the forest ecosystem spurred by increasing population and poverty-driven forest-dependent local economy. Containment efforts are being hampered by weak and fragile health systems, including public health surveillance and weak governance, certain socio-anthropological factors, fast travels (improved transport systems) and globalization. The societal impacts of the EBV outbreak are grave, including economic shutdown, weakening of socio-political systems, psychological distress, and unprecedented consumption of scarce health resources. The research and development (R&D) pipeline for product against EBV seems grossly insufficient. The outbreak of Ebola and the seeming difficulty to contain the epidemic is simply a reflection of the weak health system, poor surveillance and emergency preparedness/response, poverty and disconnect between the government
Omoleke, Semeeh Akinwale; Mohammed, Ibrahim; Saidu, Yauba
The West African sub-continent is currently experiencing its first, and ironically, the largest and longest Ebola viral diseases (EVD) outbreak ever documented in modern medical history. The current outbreak is significant in several ways, including longevity, magnitude of morbidity and mortality, occurrence outside the traditional niches, rapid spread and potential of becoming a global health tragedy. The authors provided explicit insights into the current and historical background, drivers of the epidemic, societal impacts, status of vaccines and drugs development and proffered recommendations to halt and prevent future occurrences. The authors reviewed mainly five databases and a hand search of key relevant literature. We reviewed 51 articles that were relevant up until the 18(th) of August 2014. The authors supplemented the search with reference list of relevant articles and grey literature as well as relevant Internet websites. Article searches were limited to those published either in English or French. There are strong indications that the EVD may have been triggered by increased human activities and encroachment into the forest ecosystem spurred by increasing population and poverty-driven forest-dependent local economy. Containment efforts are being hampered by weak and fragile health systems, including public health surveillance and weak governance, certain socio-anthropological factors, fast travels (improved transport systems) and globalization. The societal impacts of the EBV outbreak are grave, including economic shutdown, weakening of socio-political systems, psychological distress, and unprecedented consumption of scarce health resources. The research and development (R&D) pipeline for product against EBV seems grossly insufficient. The outbreak of Ebola and the seeming difficulty to contain the epidemic is simply a reflection of the weak health system, poor surveillance and emergency preparedness/response, poverty and disconnect between the
Fischer, D Luke; Gombash, Sara E; Kemp, Christopher J; Manfredsson, Fredric P; Polinski, Nicole K; Duffy, Megan F; Sortwell, Caryl E
Gene therapy methods are increasingly used to model Parkinson's disease (PD) in animals in an effort to test experimental therapeutics within a more relevant context to disease pathophysiology and neuropathology. We have detailed several criteria that are critical or advantageous to accurately modeling PD in a murine model or in a nonhuman primate. Using these criteria, we then evaluate approaches made to model PD using viral vectors to date, including both adeno-associated viruses and lentiviruses. Lastly, we comment on the consideration of aging as a critical factor for modeling PD.
Heneidi Zeckua, A; Zepeda Sein, C; Mateos Poumián, A; Velázquez, G
Viral haemorrhagic disease (VHD) of rabbits was introduced into Mexico from the United States of America in November 1988, following the importation of infected carcasses from China. In February 1989, the National System for Animal Health Emergencies was created, and an eradication programme was implemented at that time. The VHD virus was eradicated in 1992, by means of disease control procedures which included active epidemiological surveillance, publicity campaigns, slaughter, cleaning and disinfection of affected premises, the use of sentinel animals, serological monitoring and repopulation. The eradication programme involved the serological sampling of 39,727 rabbits (revealing an incidence of 1.4%) and the slaughter of 121,275 affected rabbits and rabbits at risk of exposure to infection. The final outbreak of the disease was recorded in April 1991. The country maintained strict epidemiological surveillance through serological testing, certification of premises free from the disease, and control of movement of animals and animal products. Mexico was declared free from the disease on 20 January 1993, becoming the first country to have eradicated VHD. The authors propose a model to evaluate the risk of introducing VHD through the importation of animals and animal products. A guide is provided to evaluate each branch of the relevant scenario tree and the principal criteria which indicate the event at each parameter.
Karunasagar, Iddya; Ababouch, Lahsen
Shrimp is an important commodity in international trade accounting for 15 % in terms of value of internationally traded seafood products which reached $102.00 billion in 2008. Aquaculture contributes to over 50 % of global shrimp production. One of the major constraints faced by shrimp aquaculture is the loss due to viral diseases like white spot syndrome, yellow head disease, and Taura syndrome. There are several examples of global spread of shrimp diseases due to importation of live shrimp for aquaculture. Though millions of tonnes of frozen or processed shrimp have been traded internationally during the last two decades despite prevalence of viral diseases in shrimp producing areas in Asia and the Americas, there is no evidence of diseases having been transmitted through shrimp imported for human consumption. The guidelines developed by the World Animal Health Organisation for movement of live animals for aquaculture, frozen crustaceans for human consumption, and the regulations implemented by some shrimp importing regions in the world are reviewed.
A high number of infectious diseases affecting livestock and companion animals are caused by pathogens of viral etiology. Ensuring the maximum standards of quality and welfare in animal production requires developing effective tools to halt and prevent the spread of those infectious diseases affecting animal husbandry. To date, one of the best strategies is to implement vaccination policies whenever possible. However many of the currently manufactured vaccines relies in classical vaccine technologies (killed or attenuated vaccines) which, under some circumstances, may not be optimal in terms of safety or adequate for widespread application in disease-free countries at risk of disease introduction. One step ahead is needed to improve and adapt vaccine manufacturing to the use of new generation vaccine technologies already tested in experimental settings. Here we present in the context of animal viral diseases of veterinary interest, an overview of some current vaccine technologies that can be approached for virus pathogens with a brief insight in the type of immunity elicited.
Idoiaga Mondragon, Nahia; Gil de Montes, Lorena; Valencia, Jose
This study examined the collective image of the 2014-2015 Ebola outbreak, to understand how people incorporate this epidemic in their everyday thinking. A free association exercise elicited by Ebola was answered by 294 people from Spain and the content was analysed using Alceste software. First, results showed that Ebola was represented as inherently African. Second, it was also depicted as a global threat creating fear. People also felt anger, and they blamed political authorities and the mass media for the failure to manage this crisis. Finally, this research underlines the importance of the social representations to understand how current outbreaks are cognitively represented and emotionally faced as a key factor to appropriately manage future epidemics.
On 19 October 2010, ten months after a devastating earthquake hit Haiti, the Haitian Ministry of Public Health and Population (MSPP) was notified of a sudden surge in patients suffering from watery diarrhea and dehydration. Two days later, the Haiti National Public Health Laboratory identified the culprit: Vibrio cholerae. On 22 October, officials announced the first cholera outbreak in Haiti in more than a century.
Di Giallonardo, Francesca; Holmes, Edward C.
Although viral emergence is commonly associated with cross-species transmission, the processes and determinants of viral evolution in a novel host environment are poorly understood. We address key questions in virus emergence and evolution using data generated from two unique natural experiments: the deliberate release of myxoma virus (MYXV) and rabbit hemorrhagic disease virus (RHDV) as biological control (biocontrol) agents against the European rabbit in Australia, and which have been of enormous benefit to Australia’s ecosystem and agricultural industries. Notably, although virulence evolution in MYXV and RHDV followed different trajectories, a strongly parallel evolutionary process was observed in Australia and Europe. These biocontrol agents were also characterised by a lack of transmission to non-target host species, suggesting that there are major barriers to successful emergence. PMID:25455418
Di Giallonardo, Francesca; Holmes, Edward C
Although viral emergence is commonly associated with cross-species transmission, the processes and determinants of viral evolution in a novel host environment are poorly understood. We address key questions in virus emergence and evolution using data generated from two unique natural experiments: the deliberate release of myxoma virus (MYXV) and rabbit hemorrhagic disease virus (RHDV) as biological control (biocontrol) agents against the European rabbit in Australia, and which have been of enormous benefit to Australia's ecosystem and agricultural industries. Notably, although virulence evolution in MYXV and RHDV followed different trajectories, a strongly parallel evolutionary process was observed in Australia and Europe. These biocontrol agents were also characterized by a lack of transmission to nontarget host species, suggesting that there are major barriers to successful emergence.
Sa'idu, L.; Jamilu, A.; Andamin, A. D.; Akpavie, S. O.
Clinical and pathological investigations were conducted on outbreaks of infectious bursal disease (IBD) in pullets under brooding using the battery cage system in a commercial poultry farm in Kaduna, Nigeria. Two consecutive outbreaks of IBD on the same farm were studied. The onset of the disease and morbidity and mortality rates were recorded. Postmortem examinations were conducted and gross lesions recorded. Tissues were collected and fixed in 10% buffered formalin and processed for histopathological examinations. In the first outbreak, 80 to 100% of the chicks were affected at the age of 4 to 5 weeks and mortality rate was 95.8% and lasted for 9 days. In the second outbreak, the mortality rate was 43.3% and it also lasted for 9 days. At the onset of the disease, the birds were also 4-week-old like in case 1. The disease was diagnosed based on clinical signs, pathology, and agar gel immunodiffusion test (AGID). Clinical signs, gross lesions, and histopathological findings were characteristic of virulent infectious bursal disease. After the first outbreak (case 1) the house was disinfected using polidine® (iodophor compound), V-ox® (inorganic peroxygen compounds), CID20® (quaternary ammonium chloride, aldehydes, and alcohol), terminator III® (phenols), and glutasan® (aldehyde and quaternary ammonium chloride). But they failed to eliminate the IBD virus from the poultry pen. PMID:27597990
Anyamba, Assaf; Linthicum, Kenneth J.; Small, Jennifer L.; Collins, Kathrine M.; Tucker, Compton J.; Pak, Edwin W.; Britch, Seth C.; Eastman, James Ronald; Pinzon, Jorge E.; Russell, Kevin L.
Background Recent clusters of outbreaks of mosquito-borne diseases (Rift Valley fever and chikungunya) in Africa and parts of the Indian Ocean islands illustrate how interannual climate variability influences the changing risk patterns of disease outbreaks. Although Rift Valley fever outbreaks have been known to follow periods of above-normal rainfall, the timing of the outbreak events has largely been unknown. Similarly, there is inadequate knowledge on climate drivers of chikungunya outbreaks. We analyze a variety of climate and satellite-derived vegetation measurements to explain the coupling between patterns of climate variability and disease outbreaks of Rift Valley fever and chikungunya. Methods and Findings We derived a teleconnections map by correlating long-term monthly global precipitation data with the NINO3.4 sea surface temperature (SST) anomaly index. This map identifies regional hot-spots where rainfall variability may have an influence on the ecology of vector borne disease. Among the regions are Eastern and Southern Africa where outbreaks of chikungunya and Rift Valley fever occurred 2004–2009. Chikungunya and Rift Valley fever case locations were mapped to corresponding climate data anomalies to understand associations between specific anomaly patterns in ecological and climate variables and disease outbreak patterns through space and time. From these maps we explored associations among Rift Valley fever disease occurrence locations and cumulative rainfall and vegetation index anomalies. We illustrated the time lag between the driving climate conditions and the timing of the first case of Rift Valley fever. Results showed that reported outbreaks of Rift Valley fever occurred after ∼3–4 months of sustained above-normal rainfall and associated green-up in vegetation, conditions ideal for Rift Valley fever mosquito vectors. For chikungunya we explored associations among surface air temperature, precipitation anomalies, and chikungunya outbreak
Mathur, P K; Herrero-Medrano, J M; Alexandri, P; Knol, E F; ten Napel, J; Rashidi, H; Mulder, H A
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
Castañón-González, Jorge Alberto; Macías, Alejandro E.; Samaniego, José Lino; Buhse, Thomas; Villanueva-Martínez, Sebastián
A severe respiratory disease epidemic outbreak correlates with a high demand of specific supplies and specialized personnel to hold it back in a wide region or set of regions; these supplies would be beds, storage areas, hemodynamic monitors, and mechanical ventilators, as well as physicians, respiratory technicians, and specialized nurses. We describe an online cumulative sum based model named Overcrowd-Severe-Respiratory-Disease-Index based on the Modified Overcrowd Index that simultaneously monitors and informs the demand of those supplies and personnel in a healthcare network generating early warnings of severe respiratory disease epidemic outbreaks through the interpretation of such variables. A post hoc historical archive is generated, helping physicians in charge to improve the transit and future allocation of supplies in the entire hospital network during the outbreak. The model was thoroughly verified in a virtual scenario, generating multiple epidemic outbreaks in a 6-year span for a 13-hospital network. When it was superimposed over the H1N1 influenza outbreak census (2008–2010) taken by the National Institute of Medical Sciences and Nutrition Salvador Zubiran in Mexico City, it showed that it is an effective algorithm to notify early warnings of severe respiratory disease epidemic outbreaks with a minimal rate of false alerts. PMID:24069063
Polanco, Carlos; Castañón-González, Jorge Alberto; Macías, Alejandro E; Samaniego, José Lino; Buhse, Thomas; Villanueva-Martínez, Sebastián
A severe respiratory disease epidemic outbreak correlates with a high demand of specific supplies and specialized personnel to hold it back in a wide region or set of regions; these supplies would be beds, storage areas, hemodynamic monitors, and mechanical ventilators, as well as physicians, respiratory technicians, and specialized nurses. We describe an online cumulative sum based model named Overcrowd-Severe-Respiratory-Disease-Index based on the Modified Overcrowd Index that simultaneously monitors and informs the demand of those supplies and personnel in a healthcare network generating early warnings of severe respiratory disease epidemic outbreaks through the interpretation of such variables. A post hoc historical archive is generated, helping physicians in charge to improve the transit and future allocation of supplies in the entire hospital network during the outbreak. The model was thoroughly verified in a virtual scenario, generating multiple epidemic outbreaks in a 6-year span for a 13-hospital network. When it was superimposed over the H1N1 influenza outbreak census (2008-2010) taken by the National Institute of Medical Sciences and Nutrition Salvador Zubiran in Mexico City, it showed that it is an effective algorithm to notify early warnings of severe respiratory disease epidemic outbreaks with a minimal rate of false alerts.
Musa, Emmanuel Onunche; Adedire, Elizabeth; Adeoye, Olawunmi; Adewuyi, Peter; Waziri, Ndadilnasiya; Nguku, Patrick; Nanjuya, Miriam; Adebayo, Bisola; Fatiregun, Akinola; Enya, Bassey; Ohuabunwo, Chima; Sabitu, Kabiru; Shuaib, Faisal; Okoh, Alex; Oguntimehin, Olukayode; Onyekwere, Nnanna; Nasidi, Abdulsalami; Olayinka, Adebola
Introduction In July 2014, Nigeria experienced an outbreak of Ebola virus disease following the introduction of the disease by an ill Liberian Traveler. The Government of Nigeria with the support of Technical and Development Partners responded quickly and effectively to contain the outbreak. The epidemiological profile of the outbreak that majorly affected two States in the country in terms of person, place and time characteristics of the cases identified is hereby described. Methods Using field investigation technique, all confirmed and probable cases were identified, line-listed and analysed using Microsoft Excel 2007 by persons, time and place. Results A total of 20 confirmed and probable cases; 16 in Lagos (including the index case from Liberia) and 4 in Port Harcourt were identified. The mean age was 39.5 ± 12.4 years with over 40% within the age group 30-39 years. The most frequent exposure type was direct physical contact in 70% of all cases and 73% among health care workers. The total case-fatality was 40%; higher among healthcare workers (46%) compared with non-healthcare workers (22%). The epidemic curve initially shows a typical common source outbreak, followed by a propagated pattern. Conclusion Investigation revealed the size and spread of the outbreak and provided information on the characteristics of persons, time and place. Enhanced surveillance measures, including contact tracing and follow- up proved very useful in early case detection and containment of the outbreak. PMID:26587177
Hrudey, Steve E; Hrudey, Elizabeth J
Residents of affluent nations are remarkably lucky to have high-quality, safe drinking water supplies that most residents of modem cities enjoy, particularly when considered in contrast to the toll of death and misery that unsafe drinking water causes for most of the world's population. Some may presume that drinking-water disease outbreaks are a thing of the past, but complacency can easily arise. A review of drinking water outbreaks in developed countries over the past 3 decades reveals some of the reasons why drinking water outbreaks keep occurring when society clearly has the means to prevent them. Prevention of future outbreaks does not demand perfection, only a commitment to learn from past mistakes and to act on what has been learned.
Bull, M; Hall, I M; Leach, S; Robesyn, E
A literature review was conducted to highlight the application and potential benefit of using geographic information systems (GIS) during Legionnaires' disease outbreak investigations. Relatively few published sources were identified, however, certain types of data were found to be important in facilitating the use of GIS, namely: patient data, locations of potential sources (e.g. cooling towers), demographic data relating to the local population and meteorological data. These data were then analysed to gain a better understanding of the spatial relationships between cases and their environment, the cases' proximity to potential outbreak sources, and the modelled dispersion of contaminated aerosols. The use of GIS in an outbreak is not a replacement for traditional outbreak investigation techniques, but it can be a valuable supplement to a response.
de Wit, Emmie; Falzarano, Darryl; Onyango, Clayton; Rosenke, Kyle; Marzi, Andrea; Ochieng, Melvin; Juma, Bonventure; Fischer, Robert J.; Prescott, Joseph B.; Safronetz, David; Omballa, Victor; Owuor, Collins; Hoenen, Thomas; Groseth, Allison; van Doremalen, Neeltje; Zemtsova, Galina; Self, Joshua; Bushmaker, Trenton; McNally, Kristin; Rowe, Thomas; Emery, Shannon L.; Feldmann, Friederike; Williamson, Brandi; Nyenswah, Tolbert G.; Grolla, Allen; Strong, James E.; Kobinger, Gary; Stroeher, Ute; Rayfield, Mark; Bolay, Fatorma K.; Zoon, Kathryn C.; Stassijns, Jorgen; Tampellini, Livia; de Smet, Martin; Nichol, Stuart T.; Fields, Barry; Sprecher, Armand; Feldmann, Heinz; Massaquoi, Moses
Malaria is a major public health concern in the countries affected by the Ebola virus disease epidemic in West Africa. We determined the feasibility of using molecular malaria diagnostics during an Ebola virus disease outbreak and report the incidence of Plasmodium spp. parasitemia in persons with suspected Ebola virus infection. PMID:26814608
The risk of vector-borne disease spread is increasing due to significant changes and variability in the global climate and increasing global travel and trade. Understanding the relationships between climate variability and disease outbreak patterns are critical to the design and construction of pred...
Trop Skaza, A; Beskovnik, L; Storman, A; Ursic, S; Groboljsek, B; Kese, D
We report an outbreak of Legionnaires' disease ina nursing home in Slovenia in August 2010 affecting 15 of 234 residents. To date, Legionnaires' disease has been confirmed in four patients. Further serum analyses and genotyping of isolates are ongoing. The building's water distribution system with dead end sections has been identified as the probable source of infection.
de Wit, Emmie; Falzarano, Darryl; Onyango, Clayton; Rosenke, Kyle; Marzi, Andrea; Ochieng, Melvin; Juma, Bonventure; Fischer, Robert J; Prescott, Joseph B; Safronetz, David; Omballa, Victor; Owuor, Collins; Hoenen, Thomas; Groseth, Allison; van Doremalen, Neeltje; Zemtsova, Galina; Self, Joshua; Bushmaker, Trenton; McNally, Kristin; Rowe, Thomas; Emery, Shannon L; Feldmann, Friederike; Williamson, Brandi; Nyenswah, Tolbert G; Grolla, Allen; Strong, James E; Kobinger, Gary; Stroeher, Ute; Rayfield, Mark; Bolay, Fatorma K; Zoon, Kathryn C; Stassijns, Jorgen; Tampellini, Livia; de Smet, Martin; Nichol, Stuart T; Fields, Barry; Sprecher, Armand; Feldmann, Heinz; Massaquoi, Moses; Munster, Vincent J
Malaria is a major public health concern in the countries affected by the Ebola virus disease epidemic in West Africa. We determined the feasibility of using molecular malaria diagnostics during an Ebola virus disease outbreak and report the incidence of Plasmodium spp. parasitemia in persons with suspected Ebola virus infection.
Njeru, Ian; Zurovac, Dejan; Tipo, Shikanga O; Kareko, David; Mwau, Matilu; Morita, Kouichi
We conducted a randomized, controlled trial to test the effectiveness of a text-messaging system used for notification of disease outbreaks in Kenya. Health facilities that used the system had more timely notifications than those that did not (19.2% vs. 2.6%), indicating that technology can enhance disease surveillance in resource-limited settings. PMID:26981628
Toda, Mitsuru; Njeru, Ian; Zurovac, Dejan; O-Tipo, Shikanga; Kareko, David; Mwau, Matilu; Morita, Kouichi
We conducted a randomized, controlled trial to test the effectiveness of a text-messaging system used for notification of disease outbreaks in Kenya. Health facilities that used the system had more timely notifications than those that did not (19.2% vs. 2.6%), indicating that technology can enhance disease surveillance in resource-limited settings.
Anyamba, Assaf; Linthicum, Kenneth J.; Small, Jennifer L.; Collins, Katherine M.; Tucker, Compton J.; Pak, Edwin W.; Britch, Seth C.; Eastman, James Ronald; Pinzon, Jorge E.; Russell, Kevin L.
Recent clusters of outbreaks of mosquito-borne diseases (Rift Valley fever and chikungunya) in Africa and parts of the Indian Ocean islands illustrate how interannual climate variability influences the changing risk patterns of disease outbreaks. Extremes in rainfall (drought and flood) during the period 2004 - 2009 have privileged different disease vectors. Chikungunya outbreaks occurred during the severe drought from late 2004 to 2006 over coastal East Africa and the western Indian Ocean islands and in the later years India and Southeast Asia. The chikungunya pandemic was caused by a Central/East African genotype that appears to have been precipitated and then enhanced by global-scale and regional climate conditions in these regions. Outbreaks of Rift Valley fever occurred following excessive rainfall period from late 2006 to late 2007 in East Africa and Sudan, and then in 2008 - 2009 in Southern Africa. The shift in the outbreak patterns of Rift Valley fever from East Africa to Southern Africa followed a transition of the El Nino/Southern Oscillation (ENSO) phenomena from the warm El Nino phase (2006-2007) to the cold La Nina phase (2007-2009) and associated patterns of variability in the greater Indian Ocean basin that result in the displacement of the centres of above normal rainfall from Eastern to Southern Africa. Understanding the background patterns of climate variability both at global and regional scale and their impacts on ecological drivers of vector borne-diseases is critical in long-range planning of appropriate response and mitigation measures.
The genus Pestivirus of the family Flaviviridae consists of four recognized species: Bovine viral diarrhea virus 1 (BVDV-1), Bovine viral diarrhea virus 2 (BVDV-2), Classical swine fever virus (CSFV) And Border disease virus (BDV). Recently, atypical pestiviruses (‘HoBi’-like pestiviruses) were iden...
Goubraim, Rabia; Kabbaj, Nawal; Salihoun, Mouna; Chaoui, Zakia; Nya, M'Hamed; Amrani, Naima
Background/Aim. Metabolic Bone disorders are well-recognized extrahepatic complications of cirrhosis. The aim was to report their prevalence and the associated factors to their development in patients with viral cirrhosis. Patients and Methods. All consecutive patients with viral cirrhosis were prospectively enrolled. Parathyroid hormone, 25-hydroxyvitamin D, liver function, and phosphocalcic tests were measured in all patients. Bone mineral density was measured at the lumbar spine and total hip by dual-energy X-ray absorptiometry. Data were analyzed using SPSS software. Results. Forty-six cirrhotic patients were included with hepatitis C (87%) and hepatitis B (13%). The Child-Pugh score was grade A in 87% of cases and grade B in 13%. Thirty-seven patients had decreased bone mineral density with osteopenia in 24 patients and osteoporosis in 13 patients. Decreased 25-hydroxyvitamin D was found in 95.6% of cases. Bone disorders were significantly more frequent in old patients with low body mass index, long duration of liver disease, and low 25-hydroxyvitamin D level. None of these factors was an independent factor associated with bone disorders. Conclusion. Our study revealed a high prevalence of metabolic bone disorders among viral cirrhotic patients. Consequently, bone mineral density assessment should be performed systematically in all cirrhotic patients. PMID:27398385
Imbert, Marine; Dias-Florencio, Gabriella; Goyenvalle, Aurélie
RNA plays complex roles in normal health and disease and is becoming an important target for therapeutic intervention; accordingly, therapeutic strategies that modulate RNA function have gained great interest over the past decade. Antisense oligonucleotides (AOs) are perhaps the most promising strategy to modulate RNA expression through a variety of post binding events such as gene silencing through degradative or non-degradative mechanisms, or splicing modulation which has recently demonstrated promising results. However, AO technology still faces issues like poor cellular-uptake, low efficacy in target tissues and relatively rapid clearance from the circulation which means repeated injections are essential to complete therapeutic efficacy. To overcome these limitations, viral vectors encoding small nuclear RNAs have been engineered to shuttle antisense sequences into cells, allowing appropriate subcellular localization with pre-mRNAs and permanent correction. In this review, we outline the different strategies for antisense therapy mediated by viral vectors and provide examples of each approach. We also address the advantages and limitations of viral vector use, with an emphasis on their clinical application. PMID:28134780
Hitchcock, Penny; Chamberlain, Allison; Van Wagoner, Megan; Inglesby, Thomas V; O'Toole, Tara
This article presents a notional scheme of global surveillance and response to infectious disease outbreaks and reviews 14 international surveillance and response programs. In combination, the scheme and the programs illustrate how, in an ideal world and in the real world, infectious disease outbreaks of public health significance could be detected and contained. Notable practices and achievements of the programs are cited; these may be useful when instituting new programs or redesigning existing ones. Insufficiencies are identified in four critical areas: health infrastructure; scientific methods and concepts of operation; essential human, technical, and financial resources; and international policies. These insufficiencies challenge global surveillance of and response to infectious disease outbreaks of international importance. This article is intended to help policymakers appreciate the complexity of the problem and assess the impact and cost-effectiveness of proposed solutions. An assessment of the potential contribution of appropriate diagnostic tests to surveillance and response is included.
Patel, Radha V; Shaeer, Kristy M; Patel, Pooja; Garmaza, Aleksey; Wiangkham, Kornwalee; Franks, Rachel B; Pane, Olivia; Carris, Nicholas W
In many parts of the United States, mosquitoes were previously nuisance pests. However, they now represent a potential threat in the spread of viral diseases. The Aedes aegypti, Aedes albopictus, and Culex species mosquitoes are endemic to the United States and together may transmit a variety of viral diseases of growing concern, including West Nile virus, chikungunya, dengue fever, and Zika virus. The Centers for Disease Control and Prevention and the Environmental Protection Agency (EPA) recommend N,N-diethyl-meta-toluamide (DEET) as a first-line mosquito repellent, but for patients refusing to use DEET or other conventional repellents, guidance is limited to any EPA-registered product. Therefore, we conducted a systematic review of the literature to identify which EPA-registered personal mosquito repellent provides the best protection from A. aegypti, A. albopictus, and Culex spp. mosquitoes. We abstracted data from 62 published reports of EPA-registered mosquito repellents. The conventional repellent picaridin has the strongest data to support its use as a second-line agent, while IR3535 and oil of lemon eucalyptus are reasonably effective natural products. Citronella, catnip, and 2-undecanone offer limited protection or have limited data. These results can be used by pharmacists and other health care professionals to advise patients on the selection of an EPA-registered mosquito repellent. Regardless of the repellent chosen, it is vital for patients to follow all instructions/precautions in the product labeling to ensure safe and effective use.
Zhou, Hao; Deem, Michael
Theoretical methods of statistical mechanics are developed and applied to study the immunological response against viral disease, such as dengue. We use this theory to show how the immune response to four different dengue serotypes may be sculpted. It is the ability of avian influenza, to change and to mix, that has given rise to the fear of a new human flu pandemic. Here we propose to utilize a scale free network based stochastic model to investigate the mitigation strategies and analyze the risk.
The paper summarizes available evidence regarding the determinants of spread of Ebola virus disease, including health care and community related risk factors. It was observed that the level of uncertainty for the estimations is relatively high which may hinder to make some predictions for the future evolution of EVD outbreak. The natural history of EVD has shown that the disease may pose a problem to developed countries and may present a thread to individuals. Although observed modes of transmission mainly include direct contact and contaminated staff, high case fatality ratio and frequent contacts among individuals in developed countries are among determinants which may lead to the development of the EVD outbreak.
Singh, Sarabjeet; Schneider, David J.; Myers, Christopher R.
Branching processes have served as a model for chemical reactions, biological growth processes, and contagion (of disease, information, or fads). Through this connection, these seemingly different physical processes share some common universalities that can be elucidated by analyzing the underlying branching process. In this work we focus on coupled branching processes as a model of infectious diseases spreading from one population to another. An exceedingly important example of such coupled outbreaks are zoonotic infections that spill over from animal populations to humans. We derive several statistical quantities characterizing the first spillover event from animals to humans, including the probability of spillover, the first passage time distribution for human infection, and disease prevalence in the animal population at spillover. Large stochastic fluctuations in those quantities can make inference of the state of the system at the time of spillover difficult. Focusing on outbreaks in the human population, we then characterize the critical threshold for a large outbreak, the distribution of outbreak sizes, and associated scaling laws. These all show a strong dependence on the basic reproduction number in the animal population and indicate the existence of a novel multicritical point with altered scaling behavior. The coupling of animal and human infection dynamics has crucial implications, most importantly allowing for the possibility of large human outbreaks even when human-to-human transmission is subcritical.
de Noya, Belkisyolé Alarcón; Díaz-Bello, Zoraida; Colmenares, Cecilia; Ruiz-Guevara, Raiza; Mauriello, Luciano; Muñoz-Calderón, Arturo; Noya, Oscar
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
Farrington, C. Paddy; Noufaily, Angela; Andrews, Nick J.; Charlett, Andre
A large-scale multiple surveillance system for infectious disease outbreaks has been in operation in England and Wales since the early 1990s. Changes to the statistical algorithm at the heart of the system were proposed and the purpose of this paper is to compare two new algorithms with the original algorithm. Test data to evaluate performance are created from weekly counts of the number of cases of each of more than 2000 diseases over a twenty-year period. The time series of each disease is separated into one series giving the baseline (background) disease incidence and a second series giving disease outbreaks. One series is shifted forward by twelve months and the two are then recombined, giving a realistic series in which it is known where outbreaks have been added. The metrics used to evaluate performance include a scoring rule that appropriately balances sensitivity against specificity and is sensitive to variation in probabilities near 1. In the context of disease surveillance, a scoring rule can be adapted to reflect the size of outbreaks and this was done. Results indicate that the two new algorithms are comparable to each other and better than the algorithm they were designed to replace. PMID:27513749
Noya, Belkisyolé Alarcón de; Díaz-Bello, Zoraida; Colmenares, Cecilia; Ruiz-Guevara, Raiza; Mauriello, Luciano; Muñoz-Calderón, Arturo; Noya, Oscar
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.
The Armed Forces Health Surveillance Center, Division of Global Emerging Infections Surveillance and Response System Operations (AFHSC-GEIS) initiated a coordinated, multidisciplinary program to link data sets and information derived from eco-climatic remote sensing activities, ecologic niche modeling, arthropod vector, animal disease-host/reservoir, and human disease surveillance for febrile illnesses, into a predictive surveillance program that generates advisories and alerts on emerging infectious disease outbreaks. The program’s ultimate goal is pro-active public health practice through pre-event preparedness, prevention and control, and response decision-making and prioritization. This multidisciplinary program is rooted in over 10 years experience in predictive surveillance for Rift Valley fever outbreaks in Eastern Africa. The AFHSC-GEIS Rift Valley fever project is based on the identification and use of disease-emergence critical detection points as reliable signals for increased outbreak risk. The AFHSC-GEIS predictive surveillance program has formalized the Rift Valley fever project into a structured template for extending predictive surveillance capability to other Department of Defense (DoD)-priority vector- and water-borne, and zoonotic diseases and geographic areas. These include leishmaniasis, malaria, and Crimea-Congo and other viral hemorrhagic fevers in Central Asia and Africa, dengue fever in Asia and the Americas, Japanese encephalitis (JE) and chikungunya fever in Asia, and rickettsial and other tick-borne infections in the U.S., Africa and Asia. PMID:21388561
Knowing how to prevent and treat diabetes mellitus (DM) earlier is essential to improving outcomes. Through participating in synthesis and catabolism of glycogen, the liver helps to regulate glucose homeostasis. Viral related liver diseases are associated with glycometabolism disorders, which means effective management of viral liver diseases may be a therapeutic strategy for DM. The present article reviews the correlation between DM and liver diseases to give an update of the management of DM rooted by viral liver diseases. PMID:28352640
Bone, Eric; Grono, Shawn; Johnson, David H; Johnson, Marcia
One assumption of pandemic planning is that, during an influenza outbreak, acute care facilities may be quickly overrun with patients and as such must prepare in advance. In order to operationalise one component of a pandemic plan, Capital Health in Edmonton, Alberta, piloted a mobile triage centre facility (portable isolation containment systems) and tested pandemic influenza triage and assessment guidelines in the winter of 2006-07. The mobile model provided emergency department surge capacity for communicable disease emergencies with scalable deployment capabilities. The deployable module has several advantages over a fixed structure like a community facility. The triage facility is a location for short-term treatments, such as intravenous therapy, prescriptions, medication distribution, and self-care education, which are needed during a pandemic influenza outbreak. Decanting infectious patients away from the emergency department protects a highly-vulnerable hospitalised group from viral transmission. Based on the pilot, it is found that community triage centres are a viable support option for emergency departments in an urban setting during pandemic influenza.
Kendall, Magdalena E; Mody, Rajal K; Mahon, Barbara E; Doyle, Michael P; Herman, Karen M; Tauxe, Robert V
Fresh salsa and guacamole often contain diced raw produce, are often made in large batches, and are often poorly refrigerated, which may make them prone to contamination that can cause foodborne illness. The safety of salsa and guacamole is increasingly important as these foods gain popularity. Since 1973, local, state, and territorial health departments have voluntarily reported foodborne disease outbreaks to the Centers for Disease Control and Prevention's Foodborne Disease Outbreak Surveillance System (FDOSS) using a standard reporting form. FDOSS used paper-based reporting for 1973-1997 and switched to electronic reporting for 1998-2008. We reviewed all reports of outbreaks during 1973-2008 in which salsa or guacamole was reported as a vehicle. We found 136 outbreaks in which salsa or guacamole was reported as a possible vehicle, which resulted in 5,658 illnesses. Of these 136 salsa- or guacamole-associated (SGA) outbreaks additional possible food vehicles were reported for 33 (24%) outbreaks. There were no SGA outbreaks reported before 1984. Among reported outbreaks, most were caused by norovirus (24%), nontyphoidal Salmonella (19%), and Shigella (7%). Eighty-four percent of outbreaks were caused by foods prepared in restaurants or delis; of these, 19% reported ill foodworkers, and 29% reported improper storage as possible contributing factors. Among all foodborne disease outbreaks with a reported food vehicle during 1984-1997, 26 (0.9%) of 2,966 outbreaks were SGA, and during 1998-2008, 110 (1.4%) of 7,738 outbreaks were SGA. The number of reported foodborne disease outbreaks attributable to salsa or guacamole increased in the United States from 1984 to 2008, especially in later years, and especially in restaurants. Fresh salsa and guacamole require careful preparation and storage. Focused prevention strategies should reduce the risk of illness and ensure that these foods are enjoyed safely.
van Vuurden, Klaske; Hartvigsen, Gunnar; Bellika, Johan Gustav
Even after a decade of increased research into the problem of detecting disease outbreaks, we lack a system that can limit the number of patients affected by a potential epidemic by recognising its existence at an early stage. In this paper we suggest the use of a weighted graph representing symptoms with an exceptionally high prevalence. Cliques with high weighted edges in such a graph will represent groups of symptoms that occur together more often than usual. As a result each clique will represent the main symptoms of a disease with a high incidence rate. This will make it easier to diagnose the nature of an outbreak, to reach the affected patients at an early stage and to distinguish between outbreaks occurring simultaneously.
Rulli, Maria Cristina; Santini, Monia; Hayman, David T. S.; D’Odorico, Paolo
Tropical forests are undergoing land use change in many regions of the world, including the African continent. Human populations living close to forest margins fragmented and disturbed by deforestation may be particularly exposed to zoonotic infections because of the higher likelihood for humans to be in contact with disease reservoirs. Quantitative analysis of the nexus between deforestation and the emergence of Ebola virus disease (EVD), however, is still missing. Here we use land cover change data in conjunction with EVD outbreak records to investigate the association between recent (2004–2014) outbreaks in West and Central Africa, and patterns of land use change in the region. We show how in these EVD outbreaks the index cases in humans (i.e. spillover from wildlife reservoirs) occurred mostly in hotspots of forest fragmentation. PMID:28195145
Rulli, Maria Cristina; Santini, Monia; Hayman, David T. S.; D’Odorico, Paolo
Tropical forests are undergoing land use change in many regions of the world, including the African continent. Human populations living close to forest margins fragmented and disturbed by deforestation may be particularly exposed to zoonotic infections because of the higher likelihood for humans to be in contact with disease reservoirs. Quantitative analysis of the nexus between deforestation and the emergence of Ebola virus disease (EVD), however, is still missing. Here we use land cover change data in conjunction with EVD outbreak records to investigate the association between recent (2004–2014) outbreaks in West and Central Africa, and patterns of land use change in the region. We show how in these EVD outbreaks the index cases in humans (i.e. spillover from wildlife reservoirs) occurred mostly in hotspots of forest fragmentation.
Rulli, Maria Cristina; Santini, Monia; Hayman, David T S; D'Odorico, Paolo
Tropical forests are undergoing land use change in many regions of the world, including the African continent. Human populations living close to forest margins fragmented and disturbed by deforestation may be particularly exposed to zoonotic infections because of the higher likelihood for humans to be in contact with disease reservoirs. Quantitative analysis of the nexus between deforestation and the emergence of Ebola virus disease (EVD), however, is still missing. Here we use land cover change data in conjunction with EVD outbreak records to investigate the association between recent (2004-2014) outbreaks in West and Central Africa, and patterns of land use change in the region. We show how in these EVD outbreaks the index cases in humans (i.e. spillover from wildlife reservoirs) occurred mostly in hotspots of forest fragmentation.
Johnston, J M; Latham, R H; Meier, F A; Green, J A; Boshard, R; Mooney, B R; Edelstein, P H
Molecular laboratory techniques were used to study the epidemiology of an outbreak of nosocomial Legionnaires' disease. All patient isolates were Legionella pneumophila serogroup 1 and showed identical plasmid profiles and reactions with serogroup-specific monoclonal antibodies. L pneumophila was also cultured from four of five cooling tower water samples; however, the isolate from only one tower was serogroup 1 of the same subtype as patient isolates. Since the cases were temporally clustered and epidemiologically associated with exposure to cooling tower aerosols, the single cooling tower implicated by molecular analysis was the most likely source of the outbreak. Chlorination of cooling tower ponds has eradicated the epidemic strain. Since potable water also harbored the infecting organism and was the probable source for cooling tower contamination, decontamination of the hospital water system was also undertaken. Superchlorination of hot water holding tanks to 17 ppm on a weekly basis has effectively eradicated L pneumophila from the potable water system and appears to be a reasonable, simple, and relatively inexpensive alternative to previously described methods of control.
Pérez, S I; Rodríguez, S
The number of viruses isolated from fish has grown in the last few years as a reflection of the increasing interest in fish diseases, particularly those occurring in aquaculture facilities. Of all the described viruses, only a few are considered to be of serious concern and economic importance; they are described in this review, drawing special attention to the four families of viruses (Birnaviridae, Rhabdoviridae, Iridoviridae and Reoviridae) that have been reported in Spanish aquaculture. Infectious pancreatic necrosis virus, a member of the first family, is the most spread virus with a prevalence of 39%. Viral diseases are untreatable and because effective and safe vaccines for fish are not yet commercially available, a great care needs to be exercised when moving fish or eggs from one site or country to another. Some fish health control regulations have been legislated in Europe and USA.
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
Taha, Muhamed-Kheir; Becher, Dörte; Deghmane, Ala-Eddine; Frosch, Matthias; Hellenbrand, Wiebke; Hong, Eva; Parent du Châtelet, Isabelle; Prior, Karola; Harmsen, Dag; Vogel, Ulrich
Meningococci spread via respiratory droplets, whereas the closely related gonococci are transmitted sexually. Several outbreaks of invasive meningococcal disease have been reported in Europe and the United States among men who have sex with men (MSM). We recently identified an outbreak of serogroup C meningococcal disease among MSM in Germany and France. In this study, genomic and proteomic techniques were used to analyze the outbreak isolates. In addition, genetically identical urethritis isolates were recovered from France and Germany and included in the analysis. Genome sequencing revealed that the isolates from the outbreak among MSM and from urethritis cases belonged to a clade within clonal complex 11. Proteome analysis showed they expressed nitrite reductase, enabling anaerobic growth as previously described for gonococci. Invasive isolates from MSM, but not urethritis isolates, further expressed functional human factor H binding protein associated with enhanced survival in a newly developed transgenic mouse model expressing human factor H, a complement regulatory protein. In conclusion, our data suggest that urethritis and outbreak isolates followed a joint adaptation route including adaption to the urogenital tract. PMID:27167067
Correa, Adrienne M. S.; Ainsworth, Tracy D.; Rosales, Stephanie M.; Thurber, Andrew R.; Butler, Christopher R.; Vega Thurber, Rebecca L.
Previous studies of coral viruses have employed either microscopy or metagenomics, but few have attempted to comprehensively link the presence of a virus-like particle (VLP) to a genomic sequence. We conducted transmission electron microscopy imaging and virome analysis in tandem to characterize the most conspicuous viral types found within the dominant Pacific reef-building coral genus Acropora. Collections for this study inadvertently captured what we interpret as a natural outbreak of viral infection driven by aerial exposure of the reef flat coincident with heavy rainfall and concomitant mass bleaching. All experimental corals in this study had high titers of viral particles. Three of the dominant VLPs identified were observed in all tissue layers and budding out from the epidermis, including viruses that were ∼70, ∼120, and ∼150 nm in diameter; these VLPs all contained electron dense cores. These morphological traits are reminiscent of retroviruses, herpesviruses, and nucleocytoplasmic large DNA viruses (NCLDVs), respectively. Some 300–500 nm megavirus-like VLPs also were observed within and associated with dinoflagellate algal endosymbiont (Symbiodinium) cells. Abundant sequence similarities to a gammaretrovirus, herpesviruses, and members of the NCLDVs, based on a virome generated from five Acropora aspera colonies, corroborated these morphology-based identifications. Additionally sequence similarities to two diagnostic genes, a MutS and (based on re-annotation of sequences from another study) a DNA polymerase B gene, most closely resembled Pyramimonas orientalis virus, demonstrating the association of a cosmopolitan megavirus with Symbiodinium. We also identified several other virus-like particles in host tissues, along with sequences phylogenetically similar to circoviruses, phages, and filamentous viruses. This study suggests that viral outbreaks may be a common but previously undocumented component of natural bleaching events, particularly
Yu, Pengbo; Ma, Chaofeng; Nawaz, Muhammad; Han, Lei; Zhang, Jianfang; Du, Quanli; Zhang, Lixia; Feng, Qunling; Wang, Jingjun; Xu, Jiru
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.
Balamurugan, Vinayagamurthy; Venkatesan, Gnanavel; Sen, Arnab; Annamalai, Lakshmanan; Bhanuprakash, Veerakyathappa; Singh, Raj Kumar
Identification of pathogens or antibody response to pathogens in human and animals modulates the treatment strategies for naive population and subsequent infections. Diseases can be controlled and even eradicated based on the epidemiology and effective prophylaxis, which often depends on development of efficient diagnostics. In addition, combating newly emerging diseases in human as well as animal healthcare is challenging and is dependent on developing safe and efficient diagnostics. Detection of antibodies directed against specific antigens has been the method of choice for documenting prior infection. Other than zoonosis, development of inexpensive vaccines and diagnostics is a unique problem in animal healthcare. The advent of recombinant DNA technology and its application in the biotechnology industry has revolutionized animal healthcare. The use of recombinant DNA technology in animal disease diagnosis has improved the rapidity, specificity and sensitivity of various diagnostic assays. This is because of the absence of host cellular proteins in the recombinant derived antigen preparations that dramatically decrease the rate of false-positive reactions. Various recombinant products are used for disease diagnosis in veterinary medicine and this article discusses recombinant-based viral disease diagnostics currently used for detection of pathogens in livestock and poultry.
Marek’s disease was diagnosed based on clinical signs, gross and histopathology in 15 to 17 week-old in February of 2012 and in 10 to 13-week-old Brown laying-type chickens in December of 2012 on the same farm. The outbreak involved all the 16 houses on the farm with each house containing 20,000 chi...
PROBLEM/CONDITION: Since 1971, CDC and the U.S. Environmental Protection Agency (EPA) have maintained a collaborative surveillance system for collecting and periodically reporting data relating to occurrences and causes of waterborne-disease outbreaks (WBDOs). REPORTING PERIOD CO...
Despite the enormous relevance of zoonotic infections to world-wide public health, and despite much effort in modeling individual zoonoses, a fundamental understanding of the disease dynamics and the nature of outbreaks emanating from such a complex system is still lacking. We introduce a simple sto...
Gogoi, Polakshee; Morla, Sudhir; Kaore, Megha; Kurkure, Nitin Vasantrao
The complete genome sequence of a Newcastle disease virus (NDV) strain NDV/Chicken/Nagpur/01/12 was isolated from vaccinated chicken farms in India during outbreaks in 2012. The genome is 15,192 nucleotides in length and is classified as genotype VII in class II. PMID:25593257
PROBLEM/CONDITION: Since 1971, CDC, the U.S. Environmental Protection Agency (EPA), and the Council of State and Territorial Epidemiologists (CSTE) have maintained a collaborative surveillance system for the occurrences and causes of waterborne-disease outbreaks (WBDOs).This surv...
During the post-8th International Coral Reef Symposium field trip to the eastern Caribbean region of Panama, 3-5 July 1996, we observed an extensive outbreak of a new and significant disease of the scleractinian corals Montastraea faveolata and M. annularis. The first reported si...
Earth observing technologies, including data from with earth-orbiting satellites, coupled with new investigations and a better understanding of the impact of environmental factors on transmission dynamics of mosquito-borne diseases permitted us to forecast Rift Valley fever (RVF) outbreaks in animal...
de Jesús Durán-Avelar, Ma; Pérez-Enríquez, Ricardo; Zambrano-Zaragoza, José Francisco; Montoya-Rodríguez, Leobardo; Vázquez-Juárez, Ricardo; Vibanco-Pérez, Norberto
White spot disease (WSD) causes high mortality in cultured shrimp throughout the world. Its etiologic agent is the white spot syndrome virus (WSSV). The genomic repeat regions ORF 75, ORF 94, and ORF 125 have been used to classify WSSV isolates in epidemiological studies using PCR with specific primers and sequencing. The present study investigated the variation in nucleotide sequences from 107, 150, and 143 isolates of WSSV collected from Litopenaeus vannamei shrimp ponds with WSD outbreaks in northwestern Mexico during the period 2010-2012, in the genomic repeat regions ORFs 75, 94, and 125, respectively. The haplotypic nomenclature for each isolate was based on the number of repeat units and the position of single nucleotide polymorphisms on each ORF. We report finding 17, 43, and 66 haplotypes of ORFs 75, 94, and 125, respectively. The study found high haplotypic diversity in WSSV using the complete sequences of ORFs 94 and 125 as independent variables, but low haplotypic diversity for ORF 75. Different haplotypes of WSSV were found from region-to-region and year-to-year, though some individual haplotypes were found in different places and in more than one growing cycle. While these results suggest a high rate of mutation of the viral genome at these loci, or perhaps the introduction of new viral strains into the area, they are useful as a tool for epidemiological surveys. Two haplotypes from some of the ORFs in the same shrimp were encountered, suggesting the possibility of multiple infections.
Shen, Yanna; Adamou, Christina; Dowling, John N; Cooper, Gregory F
The goals of automated biosurveillance systems are to detect disease outbreaks early, while exhibiting few false positives. Evaluation measures currently exist to estimate the expected detection time of biosurveillance systems. Researchers also have developed models that estimate clinician detection of cases of outbreak diseases, which is a process known as clinical case finding. However, little research has been done on estimating how well biosurveillance systems augment traditional outbreak detection that is carried out by clinicians. In this paper, we introduce a general approach for doing so for non-endemic disease outbreaks, which are characteristic of bioterrorist induced diseases, such as respiratory anthrax. We first layout the basic framework, which makes minimal assumptions, and then we specialize it in several ways. We illustrate the method using a Bayesian outbreak detection algorithm called PANDA, a model of clinician outbreak detection, and simulated cases of a windborne anthrax release. This analysis derives a bound on how well we would expect PANDA to augment clinician detection of an anthrax outbreak. The results support that such analyses are useful in assessing the extent to which computer-based outbreak detection systems are expected to augment traditional clinician outbreak detection.
Garner, Michael G.; East, Iain J.; Stevenson, Mark A.; Sanson, Robert L.; Rawdon, Thomas G.; Bradhurst, Richard A.; Roche, Sharon E.; Van Ha, Pham; Kompas, Tom
Disease managers face many challenges when deciding on the most effective control strategy to manage an outbreak of foot-and-mouth disease (FMD). Decisions have to be made under conditions of uncertainty and where the situation is continually evolving. In addition, resources for control are often limited. A modeling study was carried out to identify characteristics measurable during the early phase of a FMD outbreak that might be useful as predictors of the total number of infected places, outbreak duration, and the total area under control (AUC). The study involved two modeling platforms in two countries (Australia and New Zealand) and encompassed a large number of incursion scenarios. Linear regression, classification and regression tree, and boosted regression tree analyses were used to quantify the predictive value of a set of parameters on three outcome variables of interest: the total number of infected places, outbreak duration, and the total AUC. The number of infected premises (IPs), number of pending culls, AUC, estimated dissemination ratio, and cattle density around the index herd at days 7, 14, and 21 following first detection were associated with each of the outcome variables. Regression models for the size of the AUC had the highest predictive value (R2 = 0.51–0.9) followed by the number of IPs (R2 = 0.3–0.75) and outbreak duration (R2 = 0.28–0.57). Predictability improved at later time points in the outbreak. Predictive regression models using various cut-points at day 14 to define small and large outbreaks had positive predictive values of 0.85–0.98 and negative predictive values of 0.52–0.91, with 79–97% of outbreaks correctly classified. On the strict assumption that each of the simulation models used in this study provide a realistic indication of the spread of FMD in animal populations. Our conclusion is that relatively simple metrics available early in a control program can be used to indicate the likely magnitude of an FMD
Ramadona, Aditya Lia; Lazuardi, Lutfan; Hii, Yien Ling; Holmner, Åsa; Kusnanto, Hari; Rocklöv, Joacim
Research is needed to create early warnings of dengue outbreaks to inform stakeholders and control the disease. This analysis composes of a comparative set of prediction models including only meteorological variables; only lag variables of disease surveillance; as well as combinations of meteorological and lag disease surveillance variables. Generalized linear regression models were used to fit relationships between the predictor variables and the dengue surveillance data as outcome variable on the basis of data from 2001 to 2010. Data from 2011 to 2013 were used for external validation purposed of prediction accuracy of the model. Model fit were evaluated based on prediction performance in terms of detecting epidemics, and for number of predicted cases according to RMSE and SRMSE, as well as AIC. An optimal combination of meteorology and autoregressive lag terms of dengue counts in the past were identified best in predicting dengue incidence and the occurrence of dengue epidemics. Past data on disease surveillance, as predictor alone, visually gave reasonably accurate results for outbreak periods, but not for non-outbreaks periods. A combination of surveillance and meteorological data including lag patterns up to a few years in the past showed most predictive of dengue incidence and occurrence in Yogyakarta, Indonesia. The external validation showed poorer results than the internal validation, but still showed skill in detecting outbreaks up to two months ahead. Prior studies support the fact that past meteorology and surveillance data can be predictive of dengue. However, to a less extent has prior research shown how the longer-term past disease incidence data, up to years, can play a role in predicting outbreaks in the coming years, possibly indicating cross-immunity status of the population.
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
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.
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
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.; Braunstein, Lidia Adriana
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 improve 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
On November 17, 1993, the state health departments of Louisiana, Maryland, and Mississippi notified CDC of several outbreaks of gastroenteritis occurring in their states since November 12. Preliminary epidemiologic investigations identified consumption of oysters as the primary risk factor for illness. On November 16, the Louisiana Department of Health and Hospitals (LDHH) had identified the Grand Pass and Cabbage Reef harvesting areas off the Louisiana coast as the source of oysters associated with outbreaks in Louisiana and Mississippi. Tagged oysters associated with outbreaks in Maryland were traced to the same oyster beds. The oysters harvested from these areas had been distributed throughout the United States. On November 18 and 19, the LDHH and CDC notified state epidemiologists of the potential for oyster-associated illness; outbreaks of oyster-associated gastroenteritis subsequently were identified in Florida and North Carolina. Collaborative investigations by state health officials, the Food and Drug Administration (FDA), and CDC were initiated to determine the magnitude and characteristics of the multistate outbreak, identify the etiologic agent, and trace the oysters. This report summarizes the preliminary findings of the ongoing investigation.
Hauri, A. M.; Ehrhard, I.; Frank, U.; Ammer, J.; Fell, G.; Hamouda, O.; Petersen, L.
In the week following a carnival during 19-24 February 1998, an outbreak of meningococcal disease occurred in a rural German county. The available isolates belonged to phenotype C:2a:P1.2,5 and were clonally related by pulsed-field gel electrophoresis. A case-control study was done to identify risk factors for the outbreak and to define possible vaccination target groups. Five persons aged 13-16 years who fell ill during 24-27 February were included in the study. Four of 5 cases and 10 of 32 controls visited local discotheques (OR = 8.8; P = 0.06). Cases also visited discotheques more frequently than controls (chi2 for trend, P = 0.0002). Multiple discotheques during the carnival may have been predominant locations of transmission in this outbreak. Because this risk factor was limited in time, a mass community vaccination campaign was not initiated. PMID:10722132
Torner, Nuria; Carnicer-Pont, Dolors; Castilla, Jesus; Cayla, Joan; Godoy, Pere; Dominguez, Angela
Public health activities, especially infectious disease control, depend on effective teamwork. We present the results of a pilot audit questionnaire aimed at assessing the quality of public health services in the management of VPD outbreaks. Audit questionnaire with three main areas indicators (structure, process and results) was developed. Guidelines were set and each indicator was assessed by three auditors. Differences in indicator scores according to median size of outbreaks were determined by ANOVA (significance at p≤0.05). Of 154 outbreaks; eighteen indicators had a satisfactory mean score, indicator “updated guidelines” and “timely reporting” had a poor mean score (2.84±106 and 2.44±1.67, respectively). Statistically significant differences were found according to outbreak size, in the indicators “availability of guidelines/protocol updated less than 3 years ago” (p = 0.03) and “days needed for outbreak control” (p = 0.04). Improving availability of updated guidelines, enhancing timely reporting and adequate recording of control procedures taken is needed to allow for management assessment and improvement. PMID:21249188
Torner, Nuria; Carnicer-Pont, Dolors; Castilla, Jesus; Cayla, Joan; Godoy, Pere; Dominguez, Angela
Public health activities, especially infectious disease control, depend on effective teamwork. We present the results of a pilot audit questionnaire aimed at assessing the quality of public health services in the management of VPD outbreaks. Audit questionnaire with three main areas indicators (structure, process and results) was developed. Guidelines were set and each indicator was assessed by three auditors. Differences in indicator scores according to median size of outbreaks were determined by ANOVA (significance at p≤0.05). Of 154 outbreaks; eighteen indicators had a satisfactory mean score, indicator "updated guidelines" and "timely reporting" had a poor mean score (2.84±106 and 2.44±1.67, respectively). Statistically significant differences were found according to outbreak size, in the indicators "availability of guidelines/protocol updated less than 3 years ago" (p = 0.03) and "days needed for outbreak control" (p = 0.04). Improving availability of updated guidelines, enhancing timely reporting and adequate recording of control procedures taken is needed to allow for management assessment and improvement.
Panisello, P J; Rooney, R; Quantick, P C; Stanwell-Smith, R
Five-hundred and thirty general foodborne outbreaks of food poisoning reported in England and Wales between 1992 and 1996 were reviewed to study their application to the development and maintenance of HACCP systems. Retrospective investigations of foodborne disease outbreaks provided information on aetiological agents, food vehicles and factors that contributed to the outbreaks. Salmonella spp. and foods of animal origin (red meat, poultry and seafood) were most frequently associated with outbreaks during this period. Improper cooking, inadequate storage, cross-contamination and use of raw ingredients in the preparation of food were the most common factors contributing to outbreaks. Classification and cross tabulation of surveillance information relating to aetiological agents, food vehicles and contributory factors facilitates hazard analysis. In forming control measures and their corresponding critical limits, this approach focuses monitoring on those aspects that are critical to the safety of the product. Incorporation of epidemiological data in the documentation of HACCP systems provides assurance that the system is based on the best scientific information available.
Petrov, A A; Lebedev, V N; Kulish, V S; Pyshnaya, N S; Stovba, L F; Borisevich, S V
Epidemiologic analysis of epidemic outbreaks caused by American equine encephalitis causative agents is carried out in the review. Eastern equine encephalomyelitis (EEE), Western equine encephalomyelitis (WEE) and Venezuela equine encephalomyelitis (VEE) viruses are etiologic agents of dangerous transmissive diseases that are usually accompanied by fever and neurologic symptoms. Among the New World alphaviruses, VEE virus has the most potential danger for humans and domestic animals. Currently, enzootic strains of VEE play an increasing role as etiologic agents of human diseases. Most of the VEE cases in humans in endemic regions during inter-epidemic period are caused by infection with VEE subtype ID virus. A possibility of emergence of novel epidemic outbreaks of VEE is determined by mutations of ID subtype strains into IC subtype, and those currently pose a potential threat as an etiologic agent of the disease. Despite low morbidity, EEE and WEE are a problem for healthcare due to a relatively high frequency of lethal outcomes of the disease.
Background Acute viral necrosis virus (AVNV) is the causative agent of a serious disease resulting in high mortality in cultured Chinese scallops, Chlamys farreri. We have sequenced and analyzed the complete genome of AVNV. Results The AVNV genome is a linear, double-stranded DNA molecule of 210,993 bp with a nucleotide composition of 38.5% G + C. A total of 123 open reading frames were predicted to encode functional proteins, ranging from 41 to 1,878 amino acid residues. The DNA sequence of AVNV is 97% identical to that of ostreid herpesvirus 1 (OsHV-1), and the amino acid sequences of the encoded proteins of these two viruses are 94-100% identical. The genomic organization of AVNV is similar to that of OsHV-1, and consists of two unique regions (170.4 kb and 3.4 kb, respectively), each flanked by two inverted repeats (7.6 kb and 10.2 kb, respectively), with a third unique region (1.5 kb) situated between the two internal repeats. Conclusions Our results indicate that AVNV is a variant of OsHV-1. The AVNV genome sequence provides information useful for understanding the evolution and divergence of OsHV-1 in marine molluscs. PMID:23566284
Farid, Rabia; Khan, Mohammad Haroon; Rashid, Hamid
Poliovirus causes flaccid paralysis through the destruction of motor neurons in the CNS. Susceptibility to its infection is mainly due to the interaction in between the surface capsid proteins and its receptors on the host cell surface, important for binding, penetration and other necessary events during early infection. Receptor modification is a new approach to treat viral diseases by the modification of target proteins structure. Binding domains are modified in an effective way to make it difficult for the virus to recognize it. In this study, tolerant and intolerant induced mutations in the poliovirus receptor, VP1 and VP2 were identified and substituted in the seed sequence to get the modified versions. Substitutions causing changes in initial folding were short listed and further analyzed for high level folding, physiochemical properties and interactions. Highest RMSD values were observed in between the seed and the mutant K90F (3.265 Å) and Q130W (3.270Å) respectively. The proposed substitutions were found to have low functional impact and thus can be further tested and validated by the experimental researchers. Interactions analyses proved most of the substitutions having decreased affinity for both the VP1 and VP2 and thus are of significant importance against poliovirus. This study will play an important role for bridging computational biology to other fields of applied biology and also will provide an insight to develop resistance against viral diseases. It is also expected that same approach can also be applicable against other viruses like HCV, HIV and other in near future. PMID:22553391
Lee, Changhwan; Ki, Moran
The recent outbreak of Middle East Respiratory Syndrome (MERS) coronavirus infection in Korea resulted in large socioeconomic losses. This provoked the Korean government and the general public to recognize the importance of having a well-established system against infectious diseases. Although epidemiologic investigation is one of the most important aspects of prevention, it has been pointed out that much needs to be improved in Korea. We review here the current status of the Korean epidemiologic service and suggest possible supplementation measures. We examine the current national preventive infrastructure, including human resources such as Epidemic Intelligence Service officers, its governmental management, and related policies. In addition, we describe the practical application of these resources to the recent MERS outbreak and the progress in preventive measures. The spread of MERS demonstrated that the general readiness for emerging infectious diseases in Korea is considerably low. We believe that it is essential to increase society's investment in disease prevention. Fostering public health personnel, legislating management policies, and establishing research centers for emerging infectious diseases are potential solutions. Evaluating international preventive systems, developing cooperative measures, and initiating improvements are necessary. We evaluated the Korean epidemiologic investigation system and the public preventive measures against infectious diseases in light of the recent MERS outbreak. We suggest that governmental authorities in Korea enforce preventive policies, foster the development of highly qualified personnel, and increase investment in the public health domain of infectious disease prevention.
Lee, Changhwan; Ki, Moran
The recent outbreak of Middle East Respiratory Syndrome (MERS) coronavirus infection in Korea resulted in large socioeconomic losses. This provoked the Korean government and the general public to recognize the importance of having a well-established system against infectious diseases. Although epidemiologic investigation is one of the most important aspects of prevention, it has been pointed out that much needs to be improved in Korea. We review here the current status of the Korean epidemiologic service and suggest possible supplementation measures. We examine the current national preventive infrastructure, including human resources such as Epidemic Intelligence Service officers, its governmental management, and related policies. In addition, we describe the practical application of these resources to the recent MERS outbreak and the progress in preventive measures. The spread of MERS demonstrated that the general readiness for emerging infectious diseases in Korea is considerably low. We believe that it is essential to increase society’s investment in disease prevention. Fostering public health personnel, legislating management policies, and establishing research centers for emerging infectious diseases are potential solutions. Evaluating international preventive systems, developing cooperative measures, and initiating improvements are necessary. We evaluated the Korean epidemiologic investigation system and the public preventive measures against infectious diseases in light of the recent MERS outbreak. We suggest that governmental authorities in Korea enforce preventive policies, foster the development of highly qualified personnel, and increase investment in the public health domain of infectious disease prevention. PMID:26493654
Martin, C; Gaudin, O; Martin, H; Prades, J M; Vidalain, E
A viral etiology is often advanced to explain the origin of Bell's palsy, sudden deafness and certain vertigos. Virology findings were compared in 72 patients with either chicken pox, herpes, zona or other "viral" infections, where the viral origin was not absolutely clear, and a population of healthy volunteers. Results confirmed the indefinite viral nature of these affections. However, recent studies have shown that definite viral disorders are not always associated with an increase in antibody levels, and the intervention of a virus should not be totally discounted in some of these affections, especially as several particularly demonstrative cases have provided confirmation of a virus origin, particularly the Epstein-Barr virus.
Foot and mouth disease (FMD) is a highly infectious and contagious viral disease affecting bovidae (cattle, zebus, domestic buffaloes, yaks), sheep, goats, swine, all wild ruminants and suidae. Camelidae (camels, dromedaries, llamas, vicunas) have low susceptibility. Foot and mouth disease is caused by a RNS virus of the family Picornaviridae, genus Aphthovirus. There are seven immunologically distinct serotypes: A, O, C, SAT1, SAT2, SAT3, Asia 1. Foot and mouth disease causes significant economic loss both to countries who manage it as an endemic disease (with or without vaccination), as well as those FMD free countries which may become infected. The mortality rate is low in adult animals, but often higher in young due to myocarditis. Foot and mouth disease is endemic in parts of Asia, Africa, the Middle East and South America (sporadic outbreaks in free areas). The Office of International Epizootics (OIE), also referred to the World Organization for Animal Health maintains an official list of free countries and zones.1 The OIE Terrestrial Code (Chapter 2.2.10) provides detailed information on the categories of freedom that can be allocated to a country as well as guidelines for the surveillance for foot and mouth disease (Appendix 3.8.7). In short, countries may be completely free of FMD, free with vaccination or infected with foot and mouth disease virus (FMDV). Source of FMDV include incubating and clinically affected animals with virus present in breath, saliva, faeces, urine, milk and semen. In experimental settings virus has been detected in milk several days before the onset of clinical signs2. Additional sources of virus are meat and by-products in which pH has remained above 6.0 as well as persistently infected carrier animals. Carrier animals may include cattle and water buffalo; convalescent animals and exposed vaccinates (virus persists in the oropharynx for up to 30 months in cattle or longer in buffalo, 9 months in sheep). Pigs do not become carriers
Cole, Jennifer; Watkins, Chris
This paper presents the findings of research carried out into the information-seeking behaviour, and information requirements of a small sample of international workers stationed in West Africa during the Zaire Ebola virus outbreak of 2014-15. The research study under which these results were obtained was part of exploratory research for a PhD focused on the use, and potential uses, of social media platforms during serious disease outbreaks that might be used to inform policy planning for public health and emergency response interventions. Thus, the findings from this study may provide valuable insights to business continuity managers and emergency planners in making future decisions about information exchange and crisis decision-making during future serious disease outbreaks.
Werber, D; Lausević, D; Mugosa, B; Vratnica, Z; Ivanović-Nikolić, L; Zizić, L; Alexandre-Bird, A; Fiore, L; Ruggeri, F M; Di Bartolo, I; Battistone, A; Gassilloud, B; Perelle, S; Nitzan Kaluski, D; Kivi, M; Andraghetti, R; Pollock, K G J
On 24 August 2008, an outbreak alert regarding cases of acute gastroenteritis in Podgorica triggered investigations to guide control measures. From 23 August to 7 September, 1699 cases were reported in Podgorica (population 136 000) and we estimated the total size of the outbreak to be 10 000-15 000 corresponding to an attack rate of approximately 10%. We conducted an age- and neighbourhood-matched case-control study, microbiologically analysed faecal and municipal water samples and assessed the water distribution system. All cases (83/83) and 90% (80/90) [corrected] of controls drank unboiled chlorinated municipal water [matched odds ratio (mOR) 11.2, 95% confidence interval (CI), 1.6-infinity]. Consumption of bottled water was inversely associated with illness (mOR 0.3, 95% CI 0.1-0.8). Analyses of faecal samples identified six norovirus genotypes (21/38 samples) and occasionally other viruses. Multiple defects in the water distribution system were noted. These results suggest that the outbreak was caused by faecally contaminated municipal water. It is unusual to have such a large outbreak in a European city especially when the municipal water supply is chlorinated. Therefore, it is important to establish effective multiple-barrier water-treatment systems whenever possible, but even with an established chlorinated supply, sustained vigilance is central to public health.
Colville, A.; Crowley, J.; Dearden, D.; Slack, R. C.; Lee, J. V.
Twelve patients in a large teaching hospital contracted Legionnaires' disease over a period of 11 months. The source was a domestic hot water system in one of the hospital blocks, which was run at a temperature of 43 degrees C. Five different subtypes of Legionella pneumophila serogroup 1 have been isolated from water in different parts of the hospital, over a period of time. Only one subtype, Benidorm RFLP 14, was implicated in disease. Circumstantial evidence suggested that the outbreak may have been due to recent colonization of the hot water system with a virulent strain of Legionella pneumophila. The outbreak was controlled by raising the hot water temperature to 60 degrees C, but careful surveillance uncovered two further cases in the following 30 months. Persistent low numbers of Legionella pneumophila were isolated from the domestic hot water of wards where Legionnaires' disease had been contracted, until an electrolytic unit was installed releasing silver and copper ions into this supply. PMID:8432314
Thacker, S B; Bennett, J V; Tsai, T F; Fraser, D W; McDade, J E; Shepard, C C; Williams, K H; Stuart, W H; Dull, H B; Eickhoff, T C
In January 1977 an unsolved outbreak of infection at St. Elizabeth's Hospital (Washington, D.C.) that occurred in 1965 was linked with Legionnaires' disease. The link was made by fluorescent antibody testing with the bacterium isolated from tissues of persons with Legionnaires' disease in the 1976 outbreak in Philadelphia. In July and August 1965, an epidemic of severe respiratory disease characterized by abrupt onset of high fever, weakness, malaise, and nonproductive cough, frequently accompanied by radiographic evidence of pneumonia, affected at least 81 patients at St. Elizabeth's Hospital, a general psychiatric hospital. Fourteen (17%) of the affected patients died. Intensive epidemiologic and laboratory investigations in 1965 did not determine the etiology. The etiologic organism may have become airborne from sites of soil excavation.
Baluka, Sylvia Angubua
Aim: Disease outbreaks increase the cost of animal production; reduce milk and beef yield, cattle sales, farmers’ incomes, and enterprise profitability. The study assessed the economic effects of foot and mouth disease (FMD) outbreaks along the cattle marketing chain in selected study districts in Uganda. Materials and Methods: The study combined qualitative and quantitative study designs. Respondents were selected proportionally using simple random sampling from the sampling frame comprising of 224, 173, 291, and 185 farmers for Nakasongola, Nakaseke, Isingiro, and Rakai, respectively. Key informants were selected purposively. Data analysis combined descriptive, modeling, and regression analysis. Data on the socio-economic characteristics and how they influenced FMD outbreaks, cattle markets revenue losses, and the economic cost of the outbreaks were analyzed using descriptive measures including percentages, means, and frequencies. Results: Farmers with small and medium herds incurred higher control costs, whereas large herds experienced the highest milk losses. Total income earned by the actors per month at the processing level reduced by 23%. In Isingiro, bulls and cows were salvage sold at 83% and 88% less market value, i.e., a loss of $196.1 and $1,552.9 in small and medium herds, respectively. Conclusion: All actors along the cattle marketing chain incur losses during FMD outbreaks, but smallholder farmers are most affected. Control and prevention of FMD should remain the responsibility of the government if Uganda is to achieve a disease-free status that is a prerequisite for free movement and operation of cattle markets throughout the year which will boost cattle marketing. PMID:27397974
Neiger, Regg; Thomas, Milton; Das, Seema; Barnes, Michael; Fletcher, Brian; Snekvik, Kevin; Thompson, Jim
We report here the genome sequences of three Flavobacterium psychrophilum strains causing a bacterial coldwater disease (BCWD) outbreak, isolated from infected rainbow trout from hatcheries in Montana and South Dakota. The availability of these virulent outbreak-causing strain genome sequences will help further understand the pathogenesis of BCWD. PMID:26966210
Mummert, Anna; Weiss, Howard
During outbreaks of infectious diseases with high morbidity and mortality, individuals closely follow media reports of the outbreak. Many will attempt to minimize contacts with other individuals in order to protect themselves from infection and possibly death. This process is called social distancing. Social distancing strategies include restricting socializing and travel, and using barrier protections. We use modeling to show that for short-term outbreaks, social distancing can have a large influence on reducing outbreak morbidity and mortality. In particular, public health agencies working together with the media can significantly reduce the severity of an outbreak by providing timely accounts of new infections and deaths. Our models show that the most effective strategy to reduce infections is to provide this information as early as possible, though providing it well into the course of the outbreak can still have a significant effect. However, our models for long-term outbreaks indicate that reporting historic infection data can result in more infections than with no reporting at all. We examine three types of media influence and we illustrate the media influence with a simulated outbreak of a generic emerging infectious disease in a small city. Social distancing can never be complete; however, for a spectrum of outbreaks, we show that leaving isolation (stopping applying social distancing measures) for up to 4 hours each day has modest effect on the overall morbidity and mortality.
Fluctuations in climate lead to extremes in temperature, rainfall, flooding, and droughts. These climate extremes create ideal ecological conditions that promote mosquito-borne disease transmission that impact global human and animal health. One well known driver of such global scale climate fluctua...
Smales, F C; Samaranyake, L P
During the three months from March 2003 the economically vibrant city of Hong Kong was seriously dislocated after becoming 'second port of call' of the new and potentially fatal disease, Severe Acute Respiratory Syndrome (SARS). The uncertainties during that period had a significant impact on the provision of dental care. However the city's only dental hospital continued to function and to support the Faculty of Dentistry of the University of Hong Kong in educating dental students and other members of the dental team. At the time of writing no transmissions of the disease have been attributed to procedures associated with dental healthcare. This article chronicles the sequence of events during the outbreak from a dental perspective. It highlights information that may be useful to dental colleagues who might someday be confronted with similar outbreaks of newly emerged potentially lethal infections.
Lin, Mei; Wang, Xin; Liang, Dabin
Over the past decade, syndromic surveillance, as supplementation of disease surveillance, has provided possibility of early alert in a real-time way for detection of emerging infectious diseases and outbreaks of widespread infectious diseases, resulting in improvement in sensitivity of outbreak detection and public health alert capacity. This tool has been highly valued and widely used in the world, and effective implementation has been observed in China. Upon abundant literature search, the authors reviewed the progress and advance of syndromic surveillance in early alert of emerging infectious diseases and outbreaks, and analyzed the problem met in the current situation in China when implementing syndromic surveillance in local facilities, which are high cost, lack of medical information platform, lack of real-time digital alert system and lack of a comprehensive information exchange platform. The authors suggested that syndromic surveillance should be implemented considering the local situation and performed in a more effective way in the current situation. Syndromic surveillance has to be integrated into the conventional public health surveillance systems and advanced laboratory networks. Digital information system is urgently needed to achieve real-time alert.
Gaillardia plants exhibiting symptoms characteristic of viral and phytoplasmal diseases were collected at botanical gardens and floriculture farms in Lithuania. Cucumber mosaic virus was isolated from diseased plants exhibiting symptoms characterized stunting, color breaking and malformation of flo...
DeVincenzo, John P.; Wilkinson, Tom; Vaishnaw, Akshay; Cehelsky, Jeff; Meyers, Rachel; Nochur, Saraswathy; Harrison, Lisa; Meeking, Patricia; Mann, Alex; Moane, Elizabeth; Oxford, John; Pareek, Rajat; Moore, Ryves; Walsh, Ed; Studholme, Robert; Dorsett, Preston; Alvarez, Rene; Lambkin-Williams, Robert
Rationale: Respiratory syncytial virus (RSV) is the leading cause of childhood lower respiratory infection, yet viable therapies are lacking. Two major challenges have stalled antiviral development: ethical difficulties in performing pediatric proof-of-concept studies and the prevailing concept that the disease is immune-mediated rather than being driven by viral load. Objectives: The development of a human experimental wild-type RSV infection model to address these challenges. Methods: Healthy volunteers (n = 35), in five cohorts, received increasing quantities (3.0–5.4 log plaque-forming units/person) of wild-type RSV-A intranasally. Measurements and Main Results: Overall, 77% of volunteers consistently shed virus. Infection rate, viral loads, disease severity, and safety were similar between cohorts and were unrelated to quantity of RSV received. Symptoms began near the time of initial viral detection, peaked in severity near when viral load peaked, and subsided as viral loads (measured by real-time polymerase chain reaction) slowly declined. Viral loads correlated significantly with intranasal proinflammatory cytokine concentrations (IL-6 and IL-8). Increased viral load correlated consistently with increases in multiple different disease measurements (symptoms, physical examination, and amount of nasal mucus). Conclusions: Viral load appears to drive disease manifestations in humans with RSV infection. The observed parallel viral and disease kinetics support a potential clinical benefit of RSV antivirals. This reproducible model facilitates the development of future RSV therapeutics. PMID:20622030
Morla, Sudhir; Deka, Pankaj; Kumar, Sachin
Infectious bursal disease virus (IBDV) is a highly infectious disease of young chicken that predominantly affects the immune system. In the present study, we are reporting first comprehensive study of IBDV outbreaks from the Northeastern part of India. Northeast India shares a porous border with four different countries; and as a rule any outbreak in the neighboring countries substantially affects the poultry population in the adjoining states. Nucleotide sequence analysis of the VP2 gene of the IBDV isolates from the Northeastern part of India suggested the extreme virulent nature of the virus. The virulent marker amino acids (A222, I242, Q253, I256 and S299) in the hypervariable region of the Northeastern isolates were found identical with the reported very virulent strains of IBDV. A unique insertion of I/L294V was recorded in all the isolates of the Northeastern India. The study will be useful in understanding the circulating pathotypes of IBDV in India.
Furuya, Kenta; Nakajima, Hitoshi; Sasaki, Yousuke; Ishiko, Akira; Urita, Yoshihisa
Scabies is an infection caused by Sarcoptes scabiei. In developed countries, scabies remains an important public health problem in hospitals and care facilities among elderly or immunocompromised patients. There are a number of medical providers who have not experienced scabies and there has been confusion surrounding its management and prevention. Therefore, the aim of the present study was to identify the optimal approach for the management and prevention of scabies. A scabies outbreak occurred between June 2014 and October 2014 in the Toho University School of Medicine, Omori Hospital (Tokyo, Japan), and the current study investigates factors concerning the outbreak, such as disease recognition, diagnostic strategy, medical staff experience and correspondence after the outbreak occurred. Six patients were newly diagnosed with scabies including patients, medical staff and family of the medical staff. An infection control committee was implemented and required a follow-up survey of 181 people (144 patients and 37 medical staff). It took ~4 months to resolve the outbreak. Scabies is highly infectious, and sufficient knowledge is required to care for the patients and prevent the infection of healthy people. In this example, the spread of infection was controlled by prompt action. PMID:28105102
Leggat, Peter A; Melrose, Wayne
Lymphatic filariasis (LF) is the second most common parasitic disease worldwide, after malaria. It should always be considered in the differential diagnosis for military personnel returning from disease-endemic areas. Numerous outbreaks of LF have been reported in military deployments from World War II. In contrast to the presentation of LF in indigenous populations, which often involves such uncommon complications as elephantiasis and hydrocele, the clinical presentation of LF in military personnel can vary widely and is often vague and nondescript. Common symptoms are pain and swelling of the genitalia, closely followed by lymphangitis of the arms and legs. All three species produce similar disease.
manuscript. Competing Interests: The authors have declared that no competing interests exist. * E-mail: email@example.com Introduction Climate...NUMBER 6. AUTHOR (S) 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Armed Forces Health...disease outbreaks including Rift Valley fever, Murray Valley encephalitis, chikungunya, malaria, Hantavirus pulmonary syndrome, and various other
2012 24-Mar-2014 Approved for Public Release; Distribution Unlimited Research Area 7.4:Identifying a Path Towards Rapid Discrimination of Infection ...Identifying a Path Towards Rapid Discrimination of Infection Disease Outbreaks Report Title The low cost and relative ease of obtaining, producing, and...MRSA is a bacterium responsible for several difficult-to-treat infections in humans. Metagenomics: The study of metagenomes, or DNA collected
Lee, Jib Ho; Lee, Joon-Hak; Kim, Moo Sang; Park, Seog Gee
Foodborne disease (FBD) is a common food safety problem in Seoul, Republic of Korea. To identify target areas for improvement of the food safety programs, FBD outbreaks from 2002 to 2006 were analyzed with regard to facility, monthly occurrences, and causative agents. A total of 147 FBD outbreaks were reported, with an average of 29.4 FBD outbreaks per year and 49 cases per outbreak. Restaurants and school lunches were two main facilities associated with 76.2% of the outbreaks. A majority of FBD cases (73.1%) were from school lunches. The highest number of outbreaks and cases occurred in June, followed by March. Among the seven identified causative agents, norovirus was the most significant in the number of outbreaks and cases. Among the outbreaks and cases with causative agents identified, norovirus and Staphylococcus aureus were responsible for 61.7% of outbreaks and 81.5% of cases. The analysis indicates that the efficiency of current food safety programs could be enhanced if critical control points in school lunch programs are identified and incorporated in the training and inspection. Identifying risk factors for contamination of norovirus and Staphylococcus aureus would also be beneficial.
Roughton, R D
In 1971, an outbreak of a hemorrhagic disease occurred in captive and free-ranging white-tailed deer (Odocoileus virginianus) in Mammoth Cave National Park, Kentucky, Clinical signs and gross pathological lesions were consistent with those of epizootic hemorrhagic disease and bluetongue, as were serological and histopathological findings for samples sent to other laboratories. The infection rate among the 104 captive deer was 88-92%, and that among the free-ranging Park deer appeared to be similar. Mortality was negligible in the Park deer, but 65 (62%) of the captive deer died. The deaths were bimodally distributed over a 36-day period, and the mortality rate decreased from 97-100% for deer clinically ill during the first 17 days of the outbreak to 58% for deer first exhibiting clinical signs on day 16 or later. Mortality was equal in males and females, but less in yearlings than among fawns or adults. Winter mortality among survivors of the initial outbreak was associated with low ambient temperatures and sometimes fungal and bacterial abscesses, possibly sequelae or complications of the hemorrhagic disease. The pregnancy and birth rates among surviving does appeared to be normal.
Woolhouse, M. E.; Haydon, D. T.; Pearson, A.; Kitching, R. P.
Outbreaks of foot-and-mouth disease persist in dairy cattle herds in Saudi Arabia despite revaccination at intervals of 4-6 months. Vaccine trials provide data on antibody responses following vaccination. Using this information we developed a mathematical model of the decay of protective antibodies with which we estimated the fraction of susceptible animals at a given time after vaccination. The model describes the data well, suggesting over 95% take with an antibody half-life of 43 days. Farm records provided data on the time course of five outbreaks. We applied a 'SLIR' epidemiological model to these data, fitting a single parameter representing disease transmission rate. The analysis provides estimates of the basic reproduction number R(0), which may exceed 70 in some cases. We conclude that the critical intervaccination interval which would provide herd immunity against FMDV is unrealistically short, especially for heterologous challenge. We suggest that it may not be possible to prevent foot-and-mouth disease outbreaks on these farms using currently available vaccines. PMID:8666082
IR imaging in mass screening for the containment of pandemic disease is based on detecting a febril (fever) state in individuals. The ability to use IR affectively for this is dependent on a good understanding of the physiology and physics related to the pathology that we are trying to screen for and is not restricted to temperature measurements alone. The radiometric thermal data processed during real-time imaging must include calibrated reference sources, thermal pattern recognition and comparative analysis between individual people being screened. A screening test should have high `sensitivity' rather than `specificity' and to be effective the false negative rate must be very low. To achieve this the false positive rate will be higher by necessity and so a `secondary' level of screening can be implemented to bring the false positive rate to within a manageable level by the higher `specificity' secondary level of screening.
Elnekave, E; Zamir, L; Hamd, F; Even Tov, B; Klement, E
Foot and mouth disease (FMD) is considered one of the most important diseases of cattle. Recurrence of FMD outbreaks in Israel is common, even though routine vaccination of livestock is mandatory and control measures are applied during the outbreaks. Grazing beef herds are occasionally involved in these outbreaks and play an important role in disseminating the disease, due to the large efflux of animals from these herds to feedlots. Nevertheless, the risk factors for the occurrence of FMD among these herds have never been investigated. In 2011, Israel faced a large scale outbreak of serotype O FMD virus, which strongly affected beef cattle. We conducted a case-control study of 44 beef cattle herds grazing in the Golan Heights in order to determine the risk factors for FMDV infection. Data were analyzed using a generalized estimation equation (GEE) with a logit link function. Multivariable analysis was conducted for factors with p-value lower than 0.1 in the univariable analysis. The presence of calves under 6 months of age was found as a significant risk factor for FMDV infection in the univariable analysis (odds ratio (OR)=5.95, confidence intervals of 95% (CI95%)=1.59-22.29, p=0.008). This was also the only variable that remained statistically significant in the multivariable analysis. Herds in which more than 6 months between vaccination of adults and exposure had elapsed were in higher risk, albeit not statistically significant, for the occurrence of FMDV infection (OR=3.29, CI95%=0.83-12.99, p=0.089). The higher probability of infection in herds, which included young calves may be a result of their higher susceptibility due to administration of only one or no vaccine prior to the outbreak. The results of the study thus support increasing the frequency of vaccination of both cows and calves in grazing beef herds. Intensifying surveillance where young calves are abundant may also prove efficient for early detection of infected herds and for mitigating outbreaks
Hoa, Tran Thi Tuyet; Zwart, Mark P; Phuong, Nguyen T; Oanh, Dang T H; de Jong, Mart C M; Vlak, Just M
Outbreaks of white spot syndrome virus (WSSV) in shrimp culture and the relationship between the virus and virulence are not well understood. Here, we provide evidence showing that WSSV mixed-genotype infections correlate with lower outbreak incidence and that disease outbreaks correlate with single-genotype infections. We tested 573 shrimp samples from 81 shrimp ponds in the Mekong delta with outbreak or non-outbreak status. The variable number tandem repeat (VNTR) loci of WSSV were used as molecular markers for the characterization of single- and mixed-genotype infections. The overall prevalence of mixed-genotype WSSV infections was 25.7 %. Non-outbreak ponds had a significantly higher frequency of mixed-genotype infections than outbreak ponds for all VNTR loci, both at the individual shrimp as well as at the pond level. The genetic composition of WSSV populations appears to correlate with the health status of shrimp culture in ponds. The causal relationship between genotypic diversity and disease outbreaks can now be experimentally approached.
Hall, M D; Woolhouse, M E J; Rambaut, A
Genetic sequence data from pathogens present a novel means to investigate the spread of infectious disease between infected hosts or infected premises, complementing traditional contact-tracing approaches, and much recent work has gone into developing methods for this purpose. The objective is to recover the epidemic transmission tree, which identifies who infected whom. This paper reviews the various approaches that have been taken. The first step is to define a measure of difference between sequences, which must be done while taking into account such factors as recombination and convergent evolution. Three broad categories of method exist, of increasing complexity: those that assume no withinhost genetic diversity or mutation, those that assume no within-host diversity but allow mutation, and those that allow both. Until recently, the assumption was usually made that every host in the epidemic could be identified, but this is now being relaxed, and some methods are intended for sparsely sampled data, concentrating on the identification of pairs of sequences that are likely to be the result of direct transmission rather than inferring the complete transmission tree. Many of the procedures described here are available to researchers as free software.
Decaro, N; Camero, M; Greco, G; Zizzo, N; Tinelli, A; Campolo, M; Pratelli, A; Buonavoglia, C
An outbreak of canine distemper in a kennel of German shepherds in the province of Bari is reported. Six 42-day-old pups developed typical signs of canine distemper (fever, conjunctivitis, respiratory distress and enteritis) and died within 7-10 days. Neurological symptoms were observed only in one pup. Four additional pups, which had shown no sign of illness, were separated and vaccinated, but two of these developed a severe, fatal nervous form 15 days later. Post-mortem examination, carried out on two pups which died without neurological signs, showed pneumonia and enteritis, more severe in one of the two examined pups. Smears from the brain and the conjunctiva of both dogs tested positive for canine distemper virus (CDV) by an immunofluorescent assay, confirmed by the identification of viral RNA using RT-PCR. Bordetella bronchiseptica and a canine adenovirus strain, characterized as canine adenovirus type 2 by a differential PCR assay, were isolated from the lungs of the pup showing the most pronounced lesions. Furthermore, canine coronavirus was detected by PCR in the intestinal content of this pup, suggesting a multifactorial aetiology of the outbreak.
Characterisation of a SAT-1 outbreak of foot-and-mouth disease in captive African buffalo (Syncerus caffer): clinical symptoms, genetic characterisation and phylogenetic comparison of outbreak isolates.
Vosloo, W; de Klerk, L-M; Boshoff, C I; Botha, B; Dwarka, R M; Keet, D; Haydon, D T
African buffalo (Syncerus caffer) play an important role in the maintenance of the SAT types of foot-and-mouth disease (FMD) in southern Africa. These long-term carriers mostly become sub-clinically infected, maintaining the disease and posing a threat to other susceptible wildlife and domestic species. During an unrelated bovine tuberculosis experiment using captive buffalo in the Kruger National Park (KNP), an outbreak of SAT-1 occurred and was further investigated. The clinical signs were recorded and all animals demonstrated significant weight loss and lymphopenia that lasted 100 days. In addition, the mean cell volume and mean cell haemoglobin values were significantly higher than before the outbreak started. Virus was isolated from several buffalo over a period of 167 days post infection and the molecular clock estimated to be 3 x 10(-5) nucleotide substitutions per site per day. Seven amino acid changes occurred of which four occurred in hypervariable regions previously described for SAT-1. The genetic relationship of the outbreak virus was compared to buffalo viruses previously obtained from the KNP but the phylogeny was largely unresolved, therefore the relationship of this outbreak strain to others isolated from the KNP remains unclear.
Rainey, Jeanette J.; Phelps, Tiffani; Shi, Jianrong
Background Because mass gatherings create environments conducive for infectious disease transmission, public health officials may recommend postponing or canceling large gatherings during a moderate or severe pandemic. Despite these recommendations, limited empirical information exists on the frequency and characteristics of mass gathering-related respiratory disease outbreaks occurring in the United States. Methods We conducted a systematic literature review to identify articles about mass gathering-related respiratory disease outbreaks occurring in the United States from 2005 to 2014. A standard form was used to abstract information from relevant articles identified from six medical, behavioral and social science literature databases. We also analyzed data from the National Outbreaks Reporting System (NORS), maintained by the Centers for Disease Control and Prevention since 2009, to estimate the frequency of mass gathering-related respiratory disease outbreaks reported to the system. Results We identified 21 published articles describing 72 mass gathering-related respiratory disease outbreaks. Of these 72, 40 (56%) were associated with agriculture fairs and Influenza A H3N2v following probable swine exposure, and 25 (35%) with youth summer camps and pandemic Influenza A H1N1. Outbreaks of measles (n = 1) and mumps (n = 2) were linked to the international importation of disease. Between 2009 and 2013, 1,114 outbreaks were reported to NORS, including 96 respiratory disease outbreaks due to Legionella. None of these legionellosis outbreaks was linked to a mass gathering according to available data. Conclusion Mass gathering-related respiratory disease outbreaks may be uncommon in the United States, but have been reported from fairs (zoonotic transmission) as well as at camps where participants have close social contact in communal housing. International importation can also be a contributing factor. NORS collects information on certain respiratory diseases and could
Pastula, Daniel M.; Hancock, W. Thane; Bel, Martin; Biggs, Holly; Marfel, Maria; Lanciotti, Robert; Laven, Janeen; Chen, Tai-Ho; Staples, J. Erin; Fischer, Marc
Background Chikungunya virus is a mosquito-borne alphavirus which causes an acute febrile illness associated with polyarthralgia. Beginning in August 2013, clinicians from the Yap State Department of Health in the Federated States of Micronesia (FSM) identified an unusual cluster of illness which was subsequently confirmed to be chikungunya virus disease. Chikungunya virus disease previously had not been recognized in FSM. Methodology/Principal findings Information from patients presenting to healthcare facilities was collected and analyzed. During August 11, 2013, to August 10, 2014, a total of 1,761 clinical cases were reported for an attack rate of 155 clinical cases per 1,000 population. Among residents of Yap Main Island, 3% were hospitalized. There were no deaths. The outbreak began on Yap Main Island and rapidly spread throughout Yap Main Island and to three neighboring islands. Conclusions/Significance Chikungunya virus can cause explosive outbreaks with substantial morbidity. Given the increasing globalization of chikungunya virus, strong surveillance systems and access to laboratory testing are essential to detect outbreaks. PMID:28248978
Ross, B C; Johnson, P D; Oppedisano, F; Marino, L; Sievers, A; Stinear, T; Hayman, J A; Veitch, M G; Robins-Browne, R M
Mycobacterium ulcerans is an environmental bacterium which causes chronic skin ulcers. Despite significant epidemiological evidence to suggest that water is the source of infection, the organism has never been identified in the environment. Environmental water samples were collected from a small town in which an outbreak of 29 cases had occurred in a 3-year period. These were examined by mycobacterial culture and PCR amplification. Similar to previous studies, M. ulcerans was not cultured from the water samples. However, five samples were positive for M. ulcerans by PCR. These samples were collected from a swamp and a golf course irrigation system within the outbreak area. This is the first time that M. ulcerans has been demonstrated to be present in the environment and supports the postulated epidemiology of disease due to this organism.
Scaturro, M; Fontana, S; Crippa, S; Caporali, M G; Seyler, T; Veschetti, E; Villa, G; Rota, M C; Ricci, M L
An unusually long-lasting community-acquired outbreak of Legionnaires' disease (LD) occurred in the inhabitants of a town in northern Italy from 2005 to 2008. Overall, 43 cases were diagnosed including five deaths. Hundreds of water samples were collected for Legionella isolation but only two clinical samples were obtained. Clinical strains were ST23 as were environmental isolates detected in most Legionella-positive patients' homes and those from a public fountain. Although no Legionella was found in the municipal water mains, a continuous chlorination was applied in 2008. This action resulted in a halving of cases, although incidence remained tenfold higher than the Italian average incidence until the end of 2013, when it dropped to the expected rate. Retrospective analyses of prevalent wind direction suggested that a hidden cooling tower could have been the main cause of this uncommon outbreak, highlighting the importance of implementation of cooling tower registers in supporting LD investigations.
The outbreak of Ebola virus disease, reported in West Africa in 2014, has become the largest ever one in the history. Tremendous efforts by all the parties concerned are now bringing this epidemic closer to the end, while observing a large number of cases and deaths, including health care workers.This paper features five questions:1. Why did it emerge in West Africa?2. Why has it spread so wide and intensely?3. Why were so many health care workers infected?4. Why is it being brought under control?5. Would it emerge and spread in Japan in the same way?Ebola virus transmits through human acts such as caregiving of the sick and attending a funeral, therefore an epidemic is not likely to subside naturally, but intentional interventions are needed to terminate its transmission. Who the outbreak response is meant for, either patients, the general public in the affected countries, or international communities, also determines its success or failure.
Implementing public health surveillance at mass gatherings might help detect outbreaks or possible acts of biologic terrorism and enable prompt public health intervention. In July 2005, a daily syndromic sentinel surveillance system was implemented to monitor disease and injury among approximately 43,000 youths and adults attending a 10-day camping event held every 4 years by a national youth organization. Camp activities began on July 25, 2005, and included events such as mountain boarding, rappelling, and whittling. This report describes public health surveillance and response activities during the 10-day event and presents recommendations for health surveillance at large outdoor events. Public health surveillance should be implemented at mass gatherings to facilitate rapid detection of outbreaks and other health-related events and enable public health teams to respond with timely control measures.
Johnson, N; Dicker, A; Mork, T; Marston, D A; Fooks, A R; Tryland, M; Fuglei, E; Müller, T
Periodic wildlife rabies epizootics occur in Arctic regions. The original sources of these outbreaks are rarely identified. In 1980, a wildlife epizootic of rabies occurred on the previously rabies-free Svalbard Islands, Norway. After this outbreak of rabies in the arctic fox population (Alopex lagopus), only single cases have been reported from the Islands over the following two decades. Phylogenetic characterization of four viruses isolated from infected arctic foxes from Svalbard from three different time periods suggest that the source of these epizootics could have been migration of this species from the Russian mainland. Arctic fox migration has likely contributed to the establishment of another zoonotic disease, Echinococcus multilocularis, on Svalbard in recent years.
Foot and Mouth Disease (FMD) is considered to be endemic throughout mainland South-East Asia (SEA). The South-East Asia and China FMD (SEACFMD) campaign is a regional control programme which has been ongoing since 1997. The programme encourages countries to submit reports of outbreaks regularly. This paper evolved from a collaboration with SEACFMD to evaluate 10 years worth of reporting. All publicly available outbreak reports (5237) were extracted from the ASEAN Region Animal Health Information System (ARAHIS) for the period from 2000 to mid 2010. These reports included date, outbreak location (at the province and district level) and serotype (if known) plus information on the outbreak size and affected species. Not all records had complete information on the population at-risk or the number of animals affected. This data was transferred into a spatially enabled database (along with data from other sources) and analysed using R and SaTScan. Outbreak serotype was unknown in 2264 (43%) of reports and some countries had very few laboratory confirmed cases (range <1-86%). Outbreak reports were standardised by number of villages in each province. Outbreak intensity varied however there did not appear to be a consistent pattern, nor was there any seasonal trend in outbreaks. Spatial and spatio-temporal cluster detection methods were applied. These identified significant clusters of disease reports. FMD is endemic across the region but is not uniformly present. ARAHIS reports can be regarded as indicators of disease reporting: there may be reports in which laboratory confirmation has not occurred, and in some cases clinical signs are inconsistent with FMD. This raises questions about the specificity of the data. Advances in decentralised testing techniques offer hope for improved verification of FMD as the cause of disease outbreaks. Advances in molecular typing may provide a substantial leap forward in understanding the circulation of FMD in South East Asia.
Lu, Ailing; Diao, Youxiang; Chen, Hao; Wang, Jiao; Ge, Pingping; Sun, Xiaoyan; Hao, Dongmin
Outbreaks of Newcastle disease in flocks of geese with high morbidity and mortality in southern and eastern China have been reported frequently since the late 1990s, which broke the traditional view that geese are considered to be the natural reservoir of Newcastle disease virus (NDV) but show few or no clinical signs after infection. In this present study, geese were infected intranasally with a local strain of NDV. Clinical disease and gross pathology were observed. Serum and immune organs were collected from geese sequentially euthanized or after disease-associated death. We studied the histopathology of immune organs by haematoxylin and eosin staining and NDV fusion protein was detected in tissues by immunohistochemistry. At the same time, the SYBR Green I real-time polymerase chain reaction assay was used to detect the viral load from the collected samples. Serum samples were tested for NDV-specific antibodies and avian influenza virus (AIV)-specific antibodies by haemagglutination inhibition (HI) test. The results showed that severe lesions and numerous positive reactions of NDV antigen were detected in the immune organs. High viral loads developed in immune organs of infected geese, correlating with the severity of clinical signs and lesions in the tissues. Furthermore, the infected geese developed low HI antibody titres to both AIV and NDV. The present study showed that the replication and dissemination of the NDV isolate was widespread in immune organs of geese. The study revealed that waterfowl may not only be a natural reservoir of NDV but also become susceptible to disease and may play a major role in the epidemiology of Newcastle disease.
... from medicines, which usually move through your bloodstream. Antibiotics do not work for viral infections. There are a few antiviral medicines available. Vaccines can help prevent you from getting many viral diseases. NIH: National Institute of Allergy and Infectious Diseases
Glynn, J. R.; Bradley, D. J.
The relationship between size of the infecting dose and severity of the resulting disease has been investigated for salmonella infections by reanalysis of data within epidemics for 32 outbreaks, and comparing data between outbreaks for 68 typhoid epidemics and 49 food-poisoning outbreaks due to salmonellas. Attack rate, incubation period, amount of infected food consumed and type of vehicle are used as proxy measures of infecting dose, while case fatality rates for typhoid and case hospitalization rates for food poisoning salmonellas were used to assess severity. Limitations of the data are discussed. Both unweighted and logit analysis models are used. There is no evidence for a dose-severity relationship for Salmonella typhi, but evidence of a correlation between dose and severity is available from within-epidemic or between-epidemic analysis, or both, for Salmonella typhimurium, S. enteritidis, S. infantis, S. newport, and S. thompson. The presence of such a relationship affects the way in which control interventions should be assessed. PMID:1468522
Kurlenda, J; Grinholc, M; Krzysztoń-Russjan, J; Wiśniewska, K
During a 1-month period, eight neonates developed staphylococcal skin disease diagnosed as a bullous impetigo in the maternity unit of the Provincial Hospital in Gdansk. An epidemiological investigation based on phenotyping and genotyping methods was performed. All neonates involved in the outbreak, their mothers and 15 staff members were screened for carriage of Staphylococcus aureus by nasal swabs. Isolated strains were compared with strains cultured from affected skin and purulent conjunctiva of infected newborns. Isolates were analyzed for the presence of the etA and etB genes using polymerase chain reaction and genotyped by pulsed-field gel electrophoresis (PFGE) and coa gene polymorphism. The analyzed S. aureus strains were methicillin-sensitive and could be divided into two groups according to antibiotyping, phage typing, coa polymorphism and PFGE pattern. The first group consisted of etA and etB negative strains, and the second one involved only the etB positive ones. Our results have shown that there were two different clusters of infection caused by two populations of S. aureus strains. Among the 15 medical staff members screened we have found seven carriers. However, phage typing revealed that distinct strains unrelated to the outbreak isolates were carried. Although we have not been able to establish the source of bacteria involved in the outbreak, our results suggest that for both groups, mothers could be the source of the infecting strains.
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.
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
Numerous outbreaks of shellfish-borne enteric virus illness have been reported worldwide. Most notable among the outbreaks are those involving norovirus illness and hepatitis A. Lessons learned from outbreak investigations indicate that most outbreaks are preventable. Anthropogenic sources of con...
Fast, Shannon M.; González, Marta C.; Markuzon, Natasha
Background Studies of cost-effective disease prevention have typically focused on the tradeoff between the cost of disease transmission and the cost of applying control measures. We present a novel approach that also accounts for the cost of social disruptions resulting from the spread of disease. These disruptions, which we call social response, can include heightened anxiety, strain on healthcare infrastructure, economic losses, or violence. Methodology The spread of disease and social response are simulated under several different intervention strategies. The modeled social response depends upon the perceived risk of the disease, the extent of disease spread, and the media involvement. Using Monte Carlo simulation, we estimate the total number of infections and total social response for each strategy. We then identify the strategy that minimizes the expected total cost of the disease, which includes the cost of the disease itself, the cost of control measures, and the cost of social response. Conclusions The model-based simulations suggest that the least-cost disease control strategy depends upon the perceived risk of the disease, as well as media intervention. The most cost-effective solution for diseases with low perceived risk was to implement moderate control measures. For diseases with higher perceived severity, such as SARS or Ebola, the most cost-effective strategy shifted toward intervening earlier in the outbreak, with greater resources. When intervention elicited increased media involvement, it remained important to control high severity diseases quickly. For moderate severity diseases, however, it became most cost-effective to implement no intervention and allow the disease to run its course. Our simulation results imply that, when diseases are perceived as severe, the costs of social response have a significant influence on selecting the most cost-effective strategy. PMID:26288274
Anyamba, Assaf; Small, Jennifer L; Britch, Seth C; Tucker, Compton J; Pak, Edwin W; Reynolds, Curt A; Crutchfield, James; Linthicum, Kenneth J
We document significant worldwide weather anomalies that affected agriculture and vector-borne disease outbreaks during the 2010-2012 period. We utilized 2000-2012 vegetation index and land surface temperature data from NASA's satellite-based Moderate Resolution Imaging Spectroradiometer (MODIS) to map the magnitude and extent of these anomalies for diverse regions including the continental United States, Russia, East Africa, Southern Africa, and Australia. We demonstrate that shifts in temperature and/or precipitation have significant impacts on vegetation patterns with attendant consequences for agriculture and public health. Weather extremes resulted in excessive rainfall and flooding as well as severe drought, which caused ∼10 to 80% variation in major agricultural commodity production (including wheat, corn, cotton, sorghum) and created exceptional conditions for extensive mosquito-borne disease outbreaks of dengue, Rift Valley fever, Murray Valley encephalitis, and West Nile virus disease. Analysis of MODIS data provided a standardized method for quantifying the extreme weather anomalies observed during this period. Assessments of land surface conditions from satellite-based systems such as MODIS can be a valuable tool in national, regional, and global weather impact determinations.
Anyamba, Assaf; Small, Jennifer L.; Britch, Seth C.; Tucker, Compton J.; Pak, Edwin W.; Reynolds, Curt A.; Crutchfield, James; Linthicum, Kenneth J.
We document significant worldwide weather anomalies that affected agriculture and vector-borne disease outbreaks during the 2010-2012 period. We utilized 2000-2012 vegetation index and land surface temperature data from NASA's satellite-based Moderate Resolution Imaging Spectroradiometer (MODIS) to map the magnitude and extent of these anomalies for diverse regions including the continental United States, Russia, East Africa, Southern Africa, and Australia. We demonstrate that shifts in temperature and/or precipitation have significant impacts on vegetation patterns with attendant consequences for agriculture and public health. Weather extremes resulted in excessive rainfall and flooding as well as severe drought, which caused,10 to 80% variation in major agricultural commodity production (including wheat, corn, cotton, sorghum) and created exceptional conditions for extensive mosquito-borne disease outbreaks of dengue, Rift Valley fever, Murray Valley encephalitis, and West Nile virus disease. Analysis of MODIS data provided a standardized method for quantifying the extreme weather anomalies observed during this period. Assessments of land surface conditions from satellite-based systems such as MODIS can be a valuable tool in national, regional, and global weather impact determinations.
Mehlhorn, Heinz; Walldorf, Volker; Klimpel, Sven; Schmahl, Günter
In August 2006, the blue tongue virus (BTV-type South Africa serotype 8) was detected for the first time in cattle blood probes in the Netherlands, immediately followed by cases in Belgium and in cattle on German farms, which were situated close to Aachen at the border to those countries. Within less than 2 months the disease spread eastwards crossing the Rhine, southwards to Luxemburg and to Northern France. At the end of the year 2006, nearly 1,000 farms were affected in Germany. Catches on two German cattle farms proved that the ceratopogonid species Culicoides obsoletus was obviously the vector, since many females-fed and unfed ones-were found to be infected with this virus. This sudden outbreak of bluetongue disease (BTD) is surely not a primary result of global warming, but rather an effect of globalization-i.e. the intensive worldwide import and export of animals; but a hot summer, as in 2006, and a warm winter like that of the years 2006/2007 supported the new spread starting again in masses in August 2007 leading to 596 PCR-confirmed cases until then with more than 200,000 animals infected. Thus, new agents coming from elsewhere have only a chance to spread if appropriate vectors are available and the conditions remain favourable during a reasonably long period. Effects of global warming-of course-will support persistence of such outbreaks of diseases due to offering of spreading of imported viruses, bacteria and/or parasites.
Cuevas-Romero, S; Hernández-Baumgarten, E; Kennedy, S; Hernández-Jáuregui, P; Berg, M; Moreno-López, J
The persistence of porcine rubulavirus (PorPV-LPMV) in five pigs that had survived an outbreak of a natural infection was determined. After the resolution of the outbreak, each animal was housed in an isolation pen together with one sentinel pig. Approximately every 2 months thereafter one group of animals was euthanized and tissue samples taken for virological and serological analysis. Infectious virus was not isolated from any samples; antibodies to PorPV-LPMV were detected in convalescent pigs by virus neutralisation test and blocking ELISA but not in sentinel pigs. PorPV-LPMV mRNA of the nucleoprotein (NP) and phosphoprotein (P) genes was detected by a nested polymerase chain reaction (nPCR) in samples of trigeminal and optic nerves, cervical spinal cord, tonsils, salivary gland, lung and pancreas from convalescent pigs. mRNA was also detected in the midbrain, corpus callosum, or olfactory bulb in four out of five pigs by nRT-PCR, this result was confirmed by the sequencing of a 260bp PCR product of P gene region. The highest average viral copies/μg of total RNA occurred in the olfactory bulb and pancreas tissues of convalescent pigs and midbrain, tonsil and pancreas of sentinel pigs housed with the convalescent pigs. Satellitosis and gliosis of the midbrain, olfactory bulb, corpus callosum, medulla oblongata or choroid plexus were microscopically observed in four convalescent pigs. The control pig remained negative in all tests. The results indicate that PorPV-LPMV mRNA persists and induces a durable humoral immune response in pigs that have recovered from a natural infection. After a possible reactivation of the virus, it was transmitted to sentinel pigs in contact with the convalescent pigs.
Paton, David J.; Taylor, Geraldine
Vaccines remain the main tool for the control of livestock viral diseases that pose a serious threat to animal and occasionally human health, reduce food security, distort trade in animals and their products, and undermine agricultural development in poor countries. Globalization and climate change increase the likelihood for new patterns of emergence and spread of livestock viruses. Conventionally attenuated and killed virus products have had spectacular success, and recent examples include the global eradication of rinderpest and the control of bluetongue in the UK and northern Europe. However, in many cases, livestock vaccines could benefit from improvement in some properties (e.g. stability, speed of onset and duration of immunity, and breadth of cross-protection to different serotypes or strains) and in some cases are not available at all. Compared with human vaccines, uptake of livestock products is highly cost-sensitive and their use may also need to be compatible with post-vaccination screening methods to determine whether or not animals continue to be infected. Requirements and prospects for new or improved vaccines are described for some priority viral diseases with potential for transboundary spread, particularly for foot-and-mouth disease. PMID:21893540
Paton, David J; Taylor, Geraldine
Vaccines remain the main tool for the control of livestock viral diseases that pose a serious threat to animal and occasionally human health, reduce food security, distort trade in animals and their products, and undermine agricultural development in poor countries. Globalization and climate change increase the likelihood for new patterns of emergence and spread of livestock viruses. Conventionally attenuated and killed virus products have had spectacular success, and recent examples include the global eradication of rinderpest and the control of bluetongue in the UK and northern Europe. However, in many cases, livestock vaccines could benefit from improvement in some properties (e.g. stability, speed of onset and duration of immunity, and breadth of cross-protection to different serotypes or strains) and in some cases are not available at all. Compared with human vaccines, uptake of livestock products is highly cost-sensitive and their use may also need to be compatible with post-vaccination screening methods to determine whether or not animals continue to be infected. Requirements and prospects for new or improved vaccines are described for some priority viral diseases with potential for transboundary spread, particularly for foot-and-mouth disease.
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.
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
Bankiewicz, Krys; Cunningham, Janet
Methods of delivering viral vectors, particularly recombinant AAV virions, to the central nervous system (CNS) are provided for the treatment of CNS disorders, particularly those disorders which involve the neurotransmitter dopamine. The methods entail providing rAAV virions that comprise a transgene encoding aromatic amino acid decarboxylase (AADC) and administering the virions to the brain of a mammal using a non-manual pump.
Purayidathil, Fanta W; Ibrahim, Jennifer
Multistate foodborne disease outbreaks (FBDOs) pose a particular threat to public health. The study described in this article sought to describe the incidence and health outcomes of multistate FBDOs in the U.S. from 1998 to 2007. The Centers for Disease Control and Prevention's (CDC's) OutbreakNet Foodborne Outbreak online database was used to analyze FBDOs reported to and confirmed by CDC between 1998 and 2007. Univariate analysis and ANOVA were used to examine outcomes of illnesses, hospitalizations, and deaths. Over 100 multistate FBDOs occurred between 1998 and 2007, with a slight increase over time. Average illnesses, hospitalizations, and deaths were 74.075 (SD = 106.24), 14.11 (SD = 23.23), and 0.826 (SD = 2.88), respectively. Vectors most often identified as the cause of the FBDOs were Salmonella (n = 57) and E. coli (n = 30), making up 81% of all multistate outbreaks. Policy makers and health officials need to reconsider the means by which industry and government coordinate response to outbreaks--particularly across jurisdictions--to ensure an efficient and seamless system of response, particularly in the case of multistate outbreaks.
Kumar, U; Kumar, S
Newcastle disease (ND) is a highly contagious disease of poultry. The ND virus (NDV) encodes an error-prone RNA-dependent RNA polymerase which can cause high mutation rate leading to the emergence of its new antigenic variants. Antigenic difference of NDV strains may result in massive outbreak in vaccinated and unvaccinated poultry flocks around the globe. Apart from its pathogenic potential NDV has been explored as an oncolytic agent for a broad range of human cancers. In the present study, we isolated a novel NDV strain from an outbreak in chicken flock from the eastern part of India. Molecular characterization showed the NDV strain to be virulent in nature. The complete genome sequence analysis of the newly isolated strains belongs to genotype XIII. Moreover, the newly isolated strain of NDV showed positive results in various apoptotic assays in human breast cancer cells, MCF-7. The study will be useful to explore the possibility of using a newly isolated strain of NDV for virotherapy.
Bloom, Ronald M.; Buckeridge, David L.; Cheng, Karen E.
Bioterrorism and emerging infectious diseases such as influenza have spurred research into rapid outbreak detection. One primary thrust of this research has been to identify data sources that provide early indication of a disease outbreak by being leading indicators relative to other established data sources. Researchers tend to rely on the sample cross-correlation function (CCF) to quantify the association between two data sources. There has been, however, little consideration by medical informatics researchers of the influence of methodological choices on the ability of the CCF to identify a lead–lag relationship between time series. We draw on experience from the econometric and environmental health communities, and we use simulation to demonstrate that the sample CCF is highly prone to bias. Specifically, long-scale phenomena tend to overwhelm the CCF, obscuring phenomena at shorter wave lengths. Researchers seeking lead–lag relationships in surveillance data must therefore stipulate the scale length of the features of interest (e.g., short-scale spikes versus long-scale seasonal fluctuations) and then filter the data appropriately—to diminish the influence of other features, which may mask the features of interest. Otherwise, conclusions drawn from the sample CCF of bi-variate time-series data will inevitably be ambiguous and often altogether misleading. PMID:17068353
Inzana, T J; Pichichero, M E
Thirty isolates of Haemophilus influenzae type b were obtained during an outbreak of invasive H. influenzae type b disease and were classified by the electrophoretic profile of their lipopolysaccharide (LPS). The LPS was extracted by a rapid micromethod and analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and silver staining. The isolates could be divided into 1 of 14 subtypes based on the profile of two to four bands. No subtype was predominant. However, all isolates obtained from duplicate sites of the same individual were of the same subtype. Isolates obtained from two patients (6 weeks apart) who attended the same day-care center differed in LPS subtype but were identical in their major outer membrane protein electrophoretic profile. Nasopharyngeal cultures were obtained from healthy children, their immediate families, and employees of the day-care center. Of 13 H. influenzae isolates examined from these contacts, only 1 was type b, which was obtained from a day-care worker and had the same LPS subtype and major outer membrane protein electrophoretic profile as one of the disease isolates. The remaining nasopharyngeal isolates were untypable, and most, but not all, were different in LPS pattern. Thus, LPS subtyping of H. influenzae type b may be useful in examining the predominance or transmission of a strain during an outbreak and may distinguish some strains not differentiated by outer membrane protein pattern. Images PMID:6333433
In West Alabama, disease outbreaks in 2009 caused by Aeromonas hydrophila have led to an estimated loss of more than $3 million. In 2010, disease outbreak occurred again in West Alabama, causing losses of hundreds of thousands of pounds of market size channel catfish. During the 2010 disease outbrea...
Gilboa, Suzanne M.; Johansson, Michael A.; Valencia, Diana; Simeone, Regina M.; Hills, Susan L.; Polen, Kara; Jamieson, Denise J.; Petersen, Lyle R.; Honein, Margaret A.
The marked increase in infants born with microcephaly in Brazil after a 2015 outbreak of Zika virus (Zika virus) disease suggests an association between maternal Zika virus infection and congenital microcephaly. To project the timing of delivery of infants born to mothers infected during early pregnancy in 1 city in Bahia State, Brazil, we incorporated data on reported Zika virus disease cases and microcephaly cases into a graphical schematic of weekly birth cohorts. We projected that these births would occur through February 2016. Applying similar projections to a hypothetical location at which Zika virus transmission started in November, we projected that full-term infants at risk for Zika virus infection would be born during April–September 2016. We also developed a modifiable spreadsheet tool that public health officials and researchers can use for their countries to plan for deliveries of infants to women who were infected with Zika virus during different pregnancy trimesters. PMID:27088494
Reefhuis, Jennita; Gilboa, Suzanne M; Johansson, Michael A; Valencia, Diana; Simeone, Regina M; Hills, Susan L; Polen, Kara; Jamieson, Denise J; Petersen, Lyle R; Honein, Margaret A
The marked increase in infants born with microcephaly in Brazil after a 2015 outbreak of Zika virus (Zika virus) disease suggests an association between maternal Zika virus infection and congenital microcephaly. To project the timing of delivery of infants born to mothers infected during early pregnancy in 1 city in Bahia State, Brazil, we incorporated data on reported Zika virus disease cases and microcephaly cases into a graphical schematic of weekly birth cohorts. We projected that these births would occur through February 2016. Applying similar projections to a hypothetical location at which Zika virus transmission started in November, we projected that full-term infants at risk for Zika virus infection would be born during April-September 2016. We also developed a modifiable spreadsheet tool that public health officials and researchers can use for their countries to plan for deliveries of infants to women who were infected with Zika virus during different pregnancy trimesters.
Durrheim, D. N.; Harris, B. N.; Speare, R.; Billinghurst, K.
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
Senchina, David S
Infectious diseases are potential catalysts for exploring 'engaged citizen' or socioscientific themes given their interwoven economic, political, scientific and social dimensions. This article describes how an undergraduate course on the history of infectious diseases was modified to explore the impact of two 'engaged citizen' themes (poverty and technology), and to consider the ramifications of those themes on past, present and future infectious disease outbreaks. Four outbreaks were used as the foundation for the course: plague (1350s), puerperal fever (1840s), cholera (1850s) and syphilis (1930s). The first part of the article describes the general course structure and the role of university-wide 'engaged citizen' themes in its semester-specific construction. The second part of the article demonstrates how poverty and technology 'threads' were explored in each of the four historical contexts, and subsequently how they were considered in current and future contexts; appendices with lesson suggestions are provided. The third and final part of the article discusses how this specific model might be more broadly applied to other microbiology instructional contexts.
Newcomer, Benjamin W; Givens, Daniel
Both bovine viral diarrhea virus and bovine herpesvirus 1 can have significant negative reproductive impacts on cattle health. Vaccination is the primary control method for the viral pathogens in US cattle herds. Polyvalent, modified-live vaccines are recommended to provide optimal protection against various viral field strains. Of particular importance to bovine viral diarrhea control is the limitation of contact of pregnant cattle with potential viral reservoirs during the critical first 125 days of gestation.
Foo, Suan-Sin; Chen, Weiqiang; Taylor, Adam; Sheng, Kuo-Ching; Yu, Xing; Teng, Terk-Shin; Reading, Patrick C.; Blanchard, Helen; Garlanda, Cecilia; Mantovani, Alberto; Ng, Lisa F. P.; Herrero, Lara J.; Mahalingam, Suresh
The rising prevalence of arthritogenic alphavirus infections, including chikungunya virus (CHIKV) and Ross River virus (RRV), and the lack of antiviral treatments highlight the potential threat of a global alphavirus pandemic. The immune responses underlying alphavirus virulence remain enigmatic. We found that pentraxin 3 (PTX3) was highly expressed in CHIKV and RRV patients during acute disease. Overt expression of PTX3 in CHIKV patients was associated with increased viral load and disease severity. PTX3-deficient (PTX3-/-) mice acutely infected with RRV exhibited delayed disease progression and rapid recovery through diminished inflammatory responses and viral replication. Furthermore, binding of the N-terminal domain of PTX3 to RRV facilitated viral entry and replication. Thus, our study demonstrates the pivotal role of PTX3 in shaping alphavirus-triggered immunity and disease and provides new insights into alphavirus pathogenesis. PMID:25695775
Gan, Lu; O'Hanlon, Terrance P; Lai, Zhennan; Fannin, Rick; Weller, Melodie L; Rider, Lisa G; Chiorini, John A; Miller, Frederick W
Viral agents are of interest as possible autoimmune triggers due to prior reported associations and widely studied molecular mechanisms of antiviral immune responses in autoimmunity. Here we examined new viral candidates for the initiation and/or promotion of systemic autoimmune diseases (SAID), as well as possible related signaling pathways shared in the pathogenesis of those disorders. RNA isolated from peripheral blood samples from 33 twins discordant for SAID and 33 matched, unrelated healthy controls was analyzed using a custom viral-human gene microarray. Paired comparisons were made among three study groups-probands with SAID, their unaffected twins, and matched, unrelated healthy controls-using statistical and molecular pathway analyses. Probands and unaffected twins differed significantly in the expression of 537 human genes, and 107 of those were associated with viral infections. These 537 differentially expressed human genes participate in overlapping networks of several canonical, biologic pathways relating to antiviral responses and inflammation. Moreover, certain viral genes were expressed at higher levels in probands compared to either unaffected twins or unrelated, healthy controls. Interestingly, viral gene expression levels in unaffected twins appeared intermediate between those of probands and the matched, unrelated healthy controls. Of the viruses with overexpressed viral genes, herpes simplex virus-2 (HSV-2) was the only human viral pathogen identified using four distinct oligonucleotide probes corresponding to three HSV-2 genes associated with different stages of viral infection. Although the effects from immunosuppressive therapy on viral gene expression remain unclear, this exploratory study suggests a new approach to evaluate shared viral agents and antiviral immune responses that may be involved in the development of SAID.
Gan, Lu; O’Hanlon, Terrance P.; Lai, Zhennan; Fannin, Rick; Weller, Melodie L.; Rider, Lisa G.; Chiorini, John A.; Miller, Frederick W.
Viral agents are of interest as possible autoimmune triggers due to prior reported associations and widely studied molecular mechanisms of antiviral immune responses in autoimmunity. Here we examined new viral candidates for the initiation and/or promotion of systemic autoimmune diseases (SAID), as well as possible related signaling pathways shared in the pathogenesis of those disorders. RNA isolated from peripheral blood samples from 33 twins discordant for SAID and 33 matched, unrelated healthy controls was analyzed using a custom viral-human gene microarray. Paired comparisons were made among three study groups—probands with SAID, their unaffected twins, and matched, unrelated healthy controls—using statistical and molecular pathway analyses. Probands and unaffected twins differed significantly in the expression of 537 human genes, and 107 of those were associated with viral infections. These 537 differentially expressed human genes participate in overlapping networks of several canonical, biologic pathways relating to antiviral responses and inflammation. Moreover, certain viral genes were expressed at higher levels in probands compared to either unaffected twins or unrelated, healthy controls. Interestingly, viral gene expression levels in unaffected twins appeared intermediate between those of probands and the matched, unrelated healthy controls. Of the viruses with overexpressed viral genes, herpes simplex virus-2 (HSV-2) was the only human viral pathogen identified using four distinct oligonucleotide probes corresponding to three HSV-2 genes associated with different stages of viral infection. Although the effects from immunosuppressive therapy on viral gene expression remain unclear, this exploratory study suggests a new approach to evaluate shared viral agents and antiviral immune responses that may be involved in the development of SAID. PMID:26556803
Segovia Hernández, Manuel
Legionella, the causative agent of legionnaire's disease (LD), can survive and grow in amoebic cells. Free-living amoebae may play a role in the selection of virulence traits and in adaptation to survival in macrophages, and represent an important reservoir of Legionella. These amoebae may act as a Trojan horse bringing hidden bacteria within the human environments. The community outbreak of LD that occurred in Murcia in July 2001, the largest such outbreak ever reported, afforded an unusual opportunity to improve the knowledge of this disease.
Harrison, T. G.; Saunders, N. A.; Haththotuwa, A.; Hallas, G.; Birtles, R. J.; Taylor, A. G.
One hundred and seventy-nine isolates of Legionella pneumophila serogroup 1, obtained from a site associated with an outbreak of Legionnaires' disease, were examined by monoclonal antibody subgrouping, restriction fragment length polymorphism typing, restriction endonuclease analysis and plasmid content. Nine distinct phenotypes were detected but at the genotypic level all strains were closely related. The data presented indicate that phenotypic variation of a single parent strain can occur within an environmental site. The implications of these findings are discussed in relation to the investigation of outbreaks of Legionnaires' disease. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 PMID:1969803
Musto, Jennie; Gregory, Joy; Fullerton, Kathleen
Every year, Australia identifies 2–3 outbreaks associated with imported foods. To examine national authorities’ obligations under the International Health Regulations (2005), we reviewed outbreaks in 2001–2007 that implicated internationally distributed foods. Under these regulations, 6 (43%) of 14 outbreaks would have required notification to the World Health Organization. PMID:18760015
Munang’andu, Hetron M.
Studies on the epidemiology of viral diseases in aquaculture have for a long time depended on isolation of viruses from infected aquatic organisms. The role of aquatic environments in the epidemiology of viral diseases in aquaculture has not been extensively expounded mainly because of the lack of appropriate tools for environmental studies on aquatic viruses. However, the upcoming of metagenomics analyses opens great avenues in which environmental samples can be used to study the epidemiology of viral diseases outside their host species. Hence, in this review I have shown that epidemiological factors that influence the composition of viruses in different aquatic environments include ecological factors, anthropogenic activities and stocking densities of cultured organisms based on environmental metagenomics studies carried out this far. Ballast water transportation and global trade of aquatic organisms are the most common virus dispersal process identified this far. In terms of disease control for outdoor aquaculture systems, baseline data on viruses found in different environments intended for aquaculture use can be obtained to enable the design of effective disease control strategies. And as such, high-risk areas having a high specter of pathogenic viruses can be identified as an early warning system. As for the control of viral diseases for indoor recirculation aquaculture systems (RAS), the most effective disinfection methods able to eliminate pathogenic viruses from water used in RAS can be identified. Overall, the synopsis I have put forth in this review shows that environmental samples can be used to study the epidemiology of viral diseases in aquaculture using viral metagenomics analysis as an overture for the design of rational disease control strategies. PMID:28018317
Munang'andu, Hetron M
Studies on the epidemiology of viral diseases in aquaculture have for a long time depended on isolation of viruses from infected aquatic organisms. The role of aquatic environments in the epidemiology of viral diseases in aquaculture has not been extensively expounded mainly because of the lack of appropriate tools for environmental studies on aquatic viruses. However, the upcoming of metagenomics analyses opens great avenues in which environmental samples can be used to study the epidemiology of viral diseases outside their host species. Hence, in this review I have shown that epidemiological factors that influence the composition of viruses in different aquatic environments include ecological factors, anthropogenic activities and stocking densities of cultured organisms based on environmental metagenomics studies carried out this far. Ballast water transportation and global trade of aquatic organisms are the most common virus dispersal process identified this far. In terms of disease control for outdoor aquaculture systems, baseline data on viruses found in different environments intended for aquaculture use can be obtained to enable the design of effective disease control strategies. And as such, high-risk areas having a high specter of pathogenic viruses can be identified as an early warning system. As for the control of viral diseases for indoor recirculation aquaculture systems (RAS), the most effective disinfection methods able to eliminate pathogenic viruses from water used in RAS can be identified. Overall, the synopsis I have put forth in this review shows that environmental samples can be used to study the epidemiology of viral diseases in aquaculture using viral metagenomics analysis as an overture for the design of rational disease control strategies.
This paper reviews the contribution of bovine viral diarrhea viruses (BVDV) to the development of Bovine Respiratory Disease (BRD). Veterinarians and producers generally consider BRD as one of the most significant diseases affecting production in the cattle industry. BRD can affect the performance (...
Stamm, Lola V.
Ebola virus disease (EVD) is a life-threatening zoonosis caused by infection with the Ebola virus. Since the first reported EVD outbreak in the Democratic Republic of the Congo, several small outbreaks have been reported in central Africa with about 2,400 cases occurring between 1976 and 2013. The 2013–2015 EVD outbreak in west Africa is the first documented outbreak in this region and the largest ever with over 27,000 cases and more than 11,000 deaths. Although EVD transmission rates have recently decreased in west Africa, this crisis continues to threaten global health and security, particularly since infected travelers could spread EVD to other resource-limited areas of the world. Because vaccines and drugs are not yet licensed for EVD, outbreak control is dependent on the use of non-pharmaceutical interventions (e.g., infection control practices, isolation of EVD cases, contact tracing with follow-up and quarantine, sanitary burial, health education). However, delays in diagnosing and reporting EVD cases in less accessible rural areas continue to hamper control efforts. New advances in rapid diagnostics for identifying presumptive EVD cases and in mobile-based technologies for communicating critical health-related information should facilitate deployment of an early response to prevent the amplification of sporadic EVD cases into large-scale outbreaks. PMID:26175026
Iatsyshina, S B; Astakhova, T S; Romanenko, V V; Platonov, A E; Zhukova, Iu V; Braslavskaia, S I; Tartakovskiĭ, I S; Shipulin, G A
The aim of the study was to perform molecular genetic analysis based on multi-locus sequence typing in order to identify source of Legionnaires' disease outbreak in town Verkhnyaya Pyshma in July 2007 and genetic profile of the causative agent. Sequence-based typing protocol recommended by European Working Group on Legionella infection (EWGLI) was used. It was not possible to obtain satisfactory results of Fla gene sequencing for all samples. Obtained allelic profiles of other genes were typical for L. pneumophila. Allelic profiles of L. pneumophila isolated from patients were identical and matched with L. pneumophila DNA detected in water from hot water supply of domestic building, but differed from cooling tower's isolates and isolates from showerhead in apartment of one patient. Identity of 5 genes of L. pneumophila isolated from autopsy samples and from hot water of central hot water supply of domestic building confirms aspiration route of infection through hot water contaminated by the microorganism. L. pneumophila detected in water from cooling tower, showerhead in apartment of one patient, and from drainage canal of hot water supply station belonged to other allelic variants and, therefore, are not related with the outbreak.
Reuter, Tim; Xu, Weiping; Alexander, Trevor W; Gilroyed, Brandon H; Inglis, G Douglas; Larney, Francis J; Stanford, Kim; McAllister, Tim A
Intensive livestock production systems are particularly vulnerable to natural or intentional (bioterrorist) infectious disease outbreaks. Large numbers of animals housed within a confined area enables rapid dissemination of most infectious agents throughout a herd. Rapid containment is key to controlling any infectious disease outbreak, thus depopulation is often undertaken to prevent spread of a pathogen to the larger livestock population. In that circumstance, a large number of livestock carcasses and contaminated manure are generated that require rapid disposal. Composting lends itself as a rapid-response disposal method for infected carcasses as well as manure and soil that may harbor infectious agents. We designed a bio-contained mortality composting procedure and tested its efficacy for bovine tissue degradation and microbial deactivation. We used materials available on-farm or purchasable from local farm supply stores in order that the system can be implemented at the site of a disease outbreak. In this study, temperatures exceeded 55 degrees C for more than one month and infectious agents implanted in beef cattle carcasses and manure were inactivated within 14 days of composting. After 147 days, carcasses were almost completely degraded. The few long bones remaining were further degraded with an additional composting cycle in open windrows and the final mature compost was suitable for land application. Duplicate compost structures (final dimensions 25 m x 5 m x 2.4 m; L x W x H) were constructed using barley straw bales and lined with heavy black silage plastic sheeting. Each was loaded with loose straw, carcasses and manure totaling approximately 95,000 kg. A 40-cm base layer of loose barley straw was placed in each bunker, onto which were placed 16 feedlot cattle mortalities (average weight 343 kg) aligned transversely at a spacing of approximately 0.5 m. For passive aeration, lengths of flexible, perforated plastic drainage tubing (15 cm diameter) were
Natesan, Mohan; Jensen, Stig M; Keasey, Sarah L; Kamata, Teddy; Kuehne, Ana I; Stonier, Spencer W; Lutwama, Julius Julian; Lobel, Leslie; Dye, John M; Ulrich, Robert G
A detailed understanding of serological immune responses to Ebola and Marburg virus infections will facilitate the development of effective diagnostic methods, therapeutics, and vaccines. We examined antibodies from Ebola or Marburg survivors 1 to 14 years after recovery from disease, by using a microarray that displayed recombinant nucleoprotein (NP), viral protein 40 (VP40), envelope glycoprotein (GP), and inactivated whole virions from six species of filoviruses. All three outbreak cohorts exhibited significant antibody responses to antigens from the original infecting species and a pattern of additional filoviruses that varied by outbreak. NP was the most cross-reactive antigen, while GP was the most specific. Antibodies from survivors of infections by Marburg marburgvirus (MARV) species were least cross-reactive, while those from survivors of infections by Sudan virus (SUDV) species exhibited the highest cross-reactivity. Based on results revealed by the protein microarray, persistent levels of antibodies to GP, NP, and VP40 were maintained for up to 14 years after infection, and survival of infection caused by one species imparted cross-reactive antibody responses to other filoviruses.
Longini, Ira M.; Morris, J. Glenn
Mathematical modeling can be a valuable tool for studying infectious disease outbreak dynamics and simulating the effects of possible interventions. Here, we describe approaches to modeling cholera outbreaks and how models have been applied to explore intervention strategies, particularly in Haiti. Mathematical models can play an important role in formulating and evaluating complex cholera outbreak response options. Major challenges to cholera modeling are insufficient data for calibrating models and the need to tailor models for different outbreak scenarios. PMID:23412687
Hobbs, Jean-Paul A.; Frisch, Ashley J.; Newman, Stephen J.; Wakefield, Corey B.
Coral diseases represent a significant and increasing threat to coral reefs. Among the most destructive diseases is White Syndrome (WS), which is increasing in distribution and prevalence throughout the Indo-Pacific. The aim of this study was to determine taxonomic and spatial patterns in mortality rates of corals following the 2008 outbreak of WS at Christmas Island in the eastern Indian Ocean. WS mainly affected Acropora plate corals and caused total mortality of 36% of colonies across all surveyed sites and depths. Total mortality varied between sites but was generally much greater in the shallows (0–96% of colonies at 5 m depth) compared to deeper waters (0–30% of colonies at 20 m depth). Site-specific mortality rates were a reflection of the proportion of corals affected by WS at each site during the initial outbreak and were predicted by the initial cover of live Acropora plate cover. The WS outbreak had a selective impact on the coral community. Following the outbreak, live Acropora plate coral cover at 5 m depth decreased significantly from 7.0 to 0.8%, while the cover of other coral taxa remained unchanged. Observations five years after the initial outbreak revealed that total Acropora plate cover remained low and confirmed that corals that lost all their tissue due to WS did not recover. These results demonstrate that WS represents a significant and selective form of coral mortality and highlights the serious threat WS poses to coral reefs in the Indo-Pacific. PMID:26147291
Bentham, R. H.; Broadbent, C. R.
Cooling towers have been demonstrated to be amplifiers and disseminators of legionella, the causative organism of Legionnaires' disease. Community outbreaks associated with cooling towers have been reported with several common factors. Small towers (< 300 kW) have predominantly been implicated in outbreaks. Cooling tower-associated outbreaks are most frequent in autumn, and frequently implicated systems have been operated after a period of shutdown. This paper reports field study data relating system operation to legionella colonization of systems. Operating systems have been shown to be more frequently colonized by legionella than shutdown systems. In some cases operation of systems after periods of shutdown raised legionella concentrations from below detection limits to between 50 and 950 c.f.u./ml within 10 min. These data and previously reported data relating to biofilm and sediment colonization of the systems, and community outbreaks of Legionnaires' disease, have been used to develop a model explaining the seasonal nature of outbreaks associated with irregularly operated, small cooling tower systems. PMID:8405155
Ashu, Eta Ebasi; Xu, Jianping
Sexual reproduction commonly refers to the reproductive process in which genomes from two sources are combined into a single cell through mating and then the zygote genomes are partitioned to progeny cells through meiosis. Reproduction in the absence of mating and meiosis is referred to as asexual or clonal reproduction. One major advantage of sexual reproduction is that it generates genetic variation among progeny which may allow for faster adaptation of the population to novel and/or stressful environments. However, adaptation to stressful or new environments can still occur through mutation, in the absence of sex. In this review, we analyzed the relative contributions of sexual and asexual reproduction in the origin and spread of strains causing fungal infectious diseases outbreaks. The necessity of sex and the ability of asexual fungi to initiate outbreaks are discussed. We propose a framework that relates the modes of reproduction to the origin and propagation of fungal disease outbreaks. Our analyses suggest that both sexual and asexual reproduction can play critical roles in the origin of outbreak strains and that the rapid spread of outbreak strains is often accomplished through asexual expansion.
After the International Health Regulations of 2005, 194 states agreed to minimal standards to assure health; accordingly, the obligation for safeguarding appropriate laboratory diagnostic capacities has existed under international law since 15 June 2007. Basically, developing and optimizing faster and more innovative testing methods should be the main aim of public health reference laboratories in order to guarantee optimal outbreak detection, control measures, and patient management. All these measures can only be successfully implemented if microbiological primary diagnostics remain comprehensive and do not fall victim to apparent budgetary restrictions. Effective microbiological diagnostics not only help the patient who is directly affected, but also have an effect on the efforts of public health services in controlling infectious disease. In this respect, microbiological routine diagnostics differ substantially from medical-chemical laboratory diagnostics.
Baker, H J; Scrimgeour, H J
In anticipation of the need to euthanize large numbers of cattle in the event of a foreign animal disease outbreak, two models of captive bolt gun and various firearms and ammunition loads were tested in order to assess their suitability. In the first phase of the project, two models of captive bolt stunner were used in an abattoir, and assessed for effectiveness. In the second phase, several firearms and ammunition were used on isolated bovine heads and assessed for effectiveness. Little difference was found between the two captive bolt stunners. Of the firearms and ammunition evaluated, the Ruger Mini-14 and the Core-Shot round, a prefragmented projectile, were determined to be most suitable. In situations where large herds of livestock are to be depopulated, and where the restraint required for the use of captive bolt stunners is not practical, there are commercially available firearms and ammunition that are suitable for this purpose. PMID:7757921
Kadi, Adiveppa S.; Avaradi, Shivakumari R.
Background. Emergence of infectious diseases like influenza pandemic (H1N1) 2009 has become great concern, which posed new challenges to the health authorities worldwide. To control these diseases various studies have been developed in the field of mathematical modelling, which is useful tool for understanding the epidemiological dynamics and their dependence on social mixing patterns. Method. We have used Bayesian approach to quantify the disease outbreak through key epidemiological parameter basic reproduction number (R0), using effective contacts, defined as sum of the product of incidence cases and probability of generation time distribution. We have estimated R0 from daily case incidence data for pandemic influenza A/H1N1 2009 in India, for the initial phase. Result. The estimated R0 with 95% credible interval is consistent with several other studies on the same strain. Through sensitivity analysis our study indicates that infectiousness affects the estimate of R0. Conclusion. Basic reproduction number R0 provides the useful information to the public health system to do some effort in controlling the disease by using mitigation strategies like vaccination, quarantine, and so forth. PMID:25784956
Colwell, Rita R.; Rose, Joan B.; Morse, Stephen S.; Rogers, David J.; Yates, Terry L.
Recent events clearly illustrate a continued vulnerability of large populations to infectious diseases, which is related to our changing human-constructed and natural environments. A single person with multidrug-resistant tuberculosis in 2007 provided a wake-up call to the United States and global public health infrastructure, as the health professionals and the public realized that today’s ease of airline travel can potentially expose hundreds of persons to an untreatable disease associated with an infectious agent. Ease of travel, population increase, population displacement, pollution, agricultural activity, changing socioeconomic structures, and international conflicts worldwide have each contributed to infectious disease events. Today, however, nothing is larger in scale, has more potential for long-term effects, and is more uncertain than the effects of climate change on infectious disease outbreaks, epidemics, and pandemics. We discuss advances in our ability to predict these events and, in particular, the critical role that satellite imaging could play in mounting an effective response. PMID:19788799
DeBeck, Heidi J.; LeBlanc, Pamela; Mogen, Kathryn M.; Wolpert, Beverly J.; Sabo, Jonathan L.; Salter, Monique; Seelman, Sharon L.; Lance, Susan E.; Monahan, Caitlin; Steigman, David S.; Gensheimer, Kathleen
Objective Liver disease is a potential complication from using dietary supplements. This study investigated an outbreak of non-viral liver disease associated with the use of OxyELITE ProTM, a dietary supplement used for weight loss and/or muscle building. Methods Illness details were ascertained from MedWatch reports submitted to the U.S. Food and Drug Administration (FDA) describing consumers who ingested OxyELITE Pro alone or in combination with other dietary supplements. FDA's Forensic Chemistry Center analyzed samples of OxyELITE Pro. Results From February 2012 to February 2014, FDA received 114 reports of adverse events of all kinds involving consumers who ingested OxyELITE Pro. The onset of illness for the first report was December 2010 and for the last report was January 2014. Thirty-three states, two foreign nations, and Puerto Rico submitted reports. Fifty-five of the reports (48%) described liver disease in the absence of viral infection, gallbladder disease, autoimmune disease, or other known causes of liver damage. A total of 33 (60%) of these patients were hospitalized, and three underwent liver transplantation. In early 2013, OxyELITE Pro products entered the market with a formulation distinct from products sold previously. The new formulation replaced 1,3-dimethylamylamine with aegeline. However, the manufacturer failed to submit to FDA a required “new dietary ingredient” notice for the use of aegeline in OxyELITE Pro products. Laboratory analysis identified no drugs, poisons, pharmaceuticals, toxic metals, usnic acid, N-Nitroso-fenfluramine, pyrrolizidine alkaloids, aristocholic acid, or phenethylamines in the products. Conclusions Vigilant surveillance is required for adverse events linked to the use of dietary supplements. PMID:26327730
Jones-Bitton, Andria; McEwen, Scott; Pintar, Katarina; Papadopoulos, Andrew
Background Reports of outbreaks in Canada and the United States (U.S.) indicate that approximately 50% of all waterborne diseases occur in small non-community drinking water systems (SDWSs). Summarizing these investigations to identify the factors and conditions contributing to outbreaks is needed in order to help prevent future outbreaks. Objectives The objectives of this study were to: 1) identify published reports of waterborne disease outbreaks involving SDWSs in Canada and the U.S. since 1970; 2) summarize reported factors contributing to outbreaks, including water system characteristics and events surrounding the outbreaks; and 3) identify terminology used to describe SDWSs in outbreak reports. Methods Three electronic databases and grey literature sources were searched for outbreak reports involving SDWSs throughout Canada and the U.S. from 1970 to 2014. Two reviewers independently screened and extracted data related to water system characteristics and outbreak events. The data were analyzed descriptively with ‘outbreak’ as the unit of analysis. Results From a total of 1,995 citations, we identified 50 relevant articles reporting 293 unique outbreaks. Failure of an existing water treatment system (22.7%) and lack of water treatment (20.2%) were the leading causes of waterborne outbreaks in SDWSs. A seasonal trend was observed with 51% of outbreaks occurring in summer months (p<0.001). There was large variation in terminology used to describe SDWSs, and a large number of variables were not reported, including water source and whether water treatment was used (missing in 31% and 66% of reports, respectively). Conclusions More consistent reporting and descriptions of SDWSs in future outbreak reports are needed to understand the epidemiology of these outbreaks and to inform the development of targeted interventions for SDWSs. Additional monitoring of water systems that are used on a seasonal or infrequent basis would be worthwhile to inform future protection
Problem/Condition: Since 1978, CDC, the U.S. Environmental Protection Agency, and the Council of State and Territorial Epidemiologists have collaborated on the Waterborne Disease and Outbreak Surveillance System (WBDOSS) for collecting and reporting data on occurrences and causes...
Kennedy, Edward M; Cullen, Bryan R
The emergence of the CRISPR/Cas system of antiviral adaptive immunity in bacteria as a facile system for gene editing in mammalian cells may well lead to gene editing becoming a novel treatment for a range of human diseases, especially those caused by deleterious germline mutations. Another potential target for gene editing are DNA viruses that cause chronic pathogenic diseases that cannot be cured by using currently available drugs. We review the current state of this field and discuss the potential advantages and problems with using a gene editing approach as a treatment for diseases caused by DNA viruses.
Nanduri, Srinivas; Foo, Chelsea; Ngo, Van; Jarashow, Claire; Civen, Rachel; Schwartz, Ben; Holguin, John; Shearer, Eric; Zahn, Matt; Harriman, Kathleen; Winter, Kathleen; Kretz, Cecilia; Chang, How Yi; Meyer, Sarah; MacNeil, Jessica
During March 4-August 11, 2016, 25 outbreak-associated cases of meningococcal disease, including two deaths (8% case-fatality ratio), were reported in Southern California. Twenty-four of the cases were caused by serogroup C Neisseria meningitidis (NmC) and one by N. meningitidis with an undetermined serogroup (Figure). On June 24, 2016, in response to this increase in NmC cases, primarily among men who have sex with men (MSM) in Los Angeles County, the city of Long Beach, and Orange County, the California Department of Public Health (CDPH) issued a press release and health advisory, declaring an outbreak of NmC in Southern California (1).
Samir, Mohamed; Pessler, Frank
MicroRNAs (miRNAs) represent a class of small non-coding RNA (sncRNA) molecules that can regulate mRNAs by inducing their degradation or by blocking translation. Considering that miRNAs are ubiquitous, stable, and conserved across animal species, it seems feasible to exploit them for clinical applications. Unlike in human viral diseases, where some miRNA-based molecules have progressed to clinical application, in veterinary medicine, this concept is just starting to come into view. Clinically, miRNAs could represent powerful diagnostic tools to pinpoint animal viral diseases and/or prognostic tools to follow up disease progression or remission. Additionally, the possible consequences of miRNA dysregulation make them potential therapeutic targets and open the possibilities to use them as tools to generate viral disease-resistant livestock. This review presents an update of preclinical studies on using sncRNAs to combat viral diseases that affect pet and farm animals. Moreover, we discuss the possibilities and challenges of bringing these bench-based discoveries to the veterinary clinic. PMID:27092305
Zell, Roland; Krumbholz, Andi; Wutzler, Peter
Global warming is believed to induce a gradual climate change. Hence, it was predicted that tropical insects might expand their habitats thereby transmitting pathogens to humans. Although this concept is a conclusive presumption, clear evidence is still lacking--at least for viral diseases. Epidemiological data indicate that seasonality of many diseases is further influenced by strong single weather events, interannual climate phenomena, and anthropogenic factors. So far, emergence of new diseases was unlinked to global warming. Re-emergence and dispersion of diseases was correlated with translocation of pathogen-infected vectors or hosts. Coupled ocean/atmosphere circulations and 'global change' that also includes shifting of demographic, social, and economical conditions are important drivers of viral disease variability whereas global warming at best contributes.
Haapkylä, J.; Melbourne-Thomas, J.; Flavell, M.; Willis, B. L.
Coral disease is a major threat to the resilience of coral reefs; thus, understanding linkages between disease outbreaks and disturbances predicted to increase with climate change is becoming increasingly important. Coral disease surveys conducted twice yearly between 2008 and 2011 at a turbid inshore reef in the central Great Barrier Reef spanned two disturbance events, a coral bleaching event in 2009 and a severe cyclone (cyclone `Yasi') in 2011. Surveys of coral cover, community structure and disease prevalence throughout this 4-yr study provide a unique opportunity to explore cumulative impacts of disturbance events and disease for inshore coral assemblages. The principal coral disease at the study site was atramentous necrosis (AtN), and it primarily affected the key inshore, reef-building coral Montipora aequituberculata. Other diseases detected were growth anomalies, white syndrome and brown band syndrome. Diseases affected eight coral genera, although Montipora was, by far, the genus mostly affected. The prevalence of AtN followed a clear seasonal pattern, with disease outbreaks occurring only in wet seasons. Mean prevalence of AtN on Montipora spp. (63.8 % ± 3.03) was three- to tenfold greater in the wet season of 2009, which coincided with the 2009 bleaching event, than in other years. Persistent wet season outbreaks of AtN combined with the impacts of bleaching and cyclone events resulted in a 50-80 % proportional decline in total coral cover. The greatest losses of branching and tabular acroporids occurred following the low-salinity-induced bleaching event of 2009, and the greatest losses of laminar montiporids occurred following AtN outbreaks in 2009 and in 2011 following cyclone Yasi. The shift to a less diverse coral assemblage and the concomitant loss of structural complexity are likely to have long-term consequences for associated vertebrate and invertebrate communities on Magnetic Island reefs.
The effectiveness of comparing complete genomes for elucidating mechanisms of virulence in pathogenic organisms has been demonstrated recently in foodborne and waterborne human disease outbreaks. We built upon this concept to investigate virulence mechanisms in bovine respiratory disease complex (B...
Montaner, Silvia; Kufareva, Irina; Abagyan, Ruben; Gutkind, J Silvio
G protein-coupled receptors (GPCRs) represent the largest family of cell surface molecules involved in signal transduction. Surprisingly, open reading frames for multiple GPCRs were hijacked in the process of coevolution between Herpesviridae family viruses and their human and mammalian hosts. Virally encoded GPCRs (vGPCRs) evolved as parts of viral genomes, and this evolution allowed the power of host GPCR signaling circuitries to be harnessed in order to ensure viral replicative success. Phylogenetically, vGPCRs are distantly related to human chemokine receptors, although they feature several unique characteristics. Here, we describe the molecular mechanisms underlying vGPCR-mediated viral pathogenesis. These mechanisms include constitutive activity, aberrant coupling to human G proteins and β-arrestins, binding and activation by human chemokines, and dimerization with other GPCRs expressed in infected cells. The likely structural basis for these molecular events is described for the two closest viral homologs of human GPCRs. This information may aid in the development of novel targeted therapeutic strategies against viral diseases.
Wojda, Thomas R; Valenza, Pamela L; Cornejo, Kristine; McGinley, Thomas; Galwankar, Sagar C; Kelkar, Dhanashree; Sharpe, Richard P; Papadimos, Thomas J; Stawicki, Stanislaw P
The Ebola outbreak of 2014-2015 exacted a terrible toll on major countries of West Africa. Latest estimates from the World Health Organization indicate that over 11,000 lives were lost to the deadly virus since the first documented case was officially recorded. However, significant progress in the fight against Ebola was made thanks to a combination of globally-supported containment efforts, dissemination of key information to the public, the use of modern information technology resources to better track the spread of the outbreak, as well as more effective use of active surveillance, targeted travel restrictions, and quarantine procedures. This article will outline the progress made by the global public health community toward containing and eventually extinguishing this latest outbreak of Ebola. Economic consequences of the outbreak will be discussed. The authors will emphasize policies and procedures thought to be effective in containing the outbreak. In addition, we will outline selected episodes that threatened inter-continental spread of the disease. The emerging topic of post-Ebola syndrome will also be presented. Finally, we will touch on some of the diagnostic (e.g., point-of-care [POC] testing) and therapeutic (e.g., new vaccines and pharmaceuticals) developments in the fight against Ebola, and how these developments may help the global public health community fight future epidemics. PMID:26752867
Giray, Tuba; Biçer, Suat; Küçük, Öznur; Çöl, Defne; Yalvaç, Zerrin; Gürol, Yeşim; Yilmaz, Gülden; Saç, Ahmet; Mogol, Yigit
The aetiology of Kawasaki disease has not yet been precisely determined. It has been associated with a variety of bacterial and viral agents. Some viruses including human adenovirus, coronavirus, and parainfluenza virus type 3 have been isolated from patients with Kawasaki disease. Clinical presentation of patients with human coronavirus and adenovirus infections mimics Kawasaki disease. In addition, these viruses may also be detected in Kawasaki disease as a coinfection. In this report, we present four Kawasaki disease patients infected with adenovirus, coronavirus OC43/HKU1 and parainfluenza virus type 3.
Olowookere, Samuel Anu; Abioye-Kuteyi, Emmanuel Akintunde; Adepoju, Olusegun Kayode; Esan, Oluwaseun Taiwo; Adeolu, Temitope Michael; Adeoye, Tolulope Kola; Adepoju, Adesola Adebayo; Aderogba, Adedayo Titilayo
Background. Health workers are more prone to Ebola viral disease (EVD) than the general population. This study assessed the preparedness of health workers in the control and management of EVD. Methods. A descriptive cross-sectional study. Consenting 400 health workers completed a semistructured questionnaire that assessed participants' general knowledge, emergency preparedness, and control and management of EVD. Data were analysed using descriptive and inferential statistics. Results. The mean age (SD) was 34.5 ± 8.62 years ranging from 20 to 59 years. Most participants were medical doctors (24.6%) and nurses (52.2%). The majority had practised <10 years (73.8%) and were aware of the EVD outbreak in the West African subregion (85.5%). Colleagues (40%) and radio (37.2%) were their major sources of information. Only 42% had good knowledge while 27% knew that there was no vaccine presently to prevent EVD. About one-quarter (24.2%) had low risk perception. The majority (89%) felt the hospital infection control policy was inadequate to protect against EVD. The only predictor of good knowledge was participants' occupation. Conclusion. There is knowledge gap and poor infection control preparedness among respondents. Thus, knowledge and practices of health workers towards EVD need improvement.
Klein, Sabra L
The intensity and prevalence of viral infections are typically higher in males, whereas disease outcome can be worse for females. Females mount higher innate and adaptive immune responses than males, which can result in faster clearance of viruses, but also contributes to increased development of immunopathology. In response to viral vaccines, females mount higher antibody responses and experience more adverse reactions than males. The efficacy of antiviral drugs at reducing viral load differs between the sexes, and the adverse reactions to antiviral drugs are typically greater in females than males. Several variables should be considered when evaluating male/female differences in responses to viral infection and treatment: these include hormones, genes, and gender-specific factors related to access to, and compliance with, treatment. Knowledge that the sexes differ in their responses to viruses and to treatments for viral diseases should influence the recommended course of action differently for males and females. Editor's suggested further reading in BioEssays X-chromosome-located microRNAs in immunity: Might they explain male/female differences Abstract.
Brathwaite Dick, Olivia; San Martín, José L.; Montoya, Romeo H.; del Diego, Jorge; Zambrano, Betzana; Dayan, Gustavo H.
Dengue is a viral disease usually transmitted by Aedes aegypti mosquitoes. Dengue outbreaks in the Americas reported in medical literature and to the Pan American Health Organization are described. The outbreak history from 1600 to 2010 was categorized into four phases: Introduction of dengue in the Americas (1600–1946); Continental plan for the eradication of the Ae. aegypti (1947–1970) marked by a successful eradication of the mosquito in 18 continental countries by 1962; Ae. aegypti reinfestation (1971–1999) caused by the failure of the mosquito eradication program; Increased dispersion of Ae. aegypti and dengue virus circulation (2000–2010) characterized by a marked increase in the number of outbreaks. During 2010 > 1.7 million dengue cases were reported, with 50,235 severe cases and 1,185 deaths. A dramatic increase in the number of outbreaks has been reported in recent years. Urgent global action is needed to avoid further disease spread. PMID:23042846
Brathwaite Dick, Olivia; San Martín, José L; Montoya, Romeo H; del Diego, Jorge; Zambrano, Betzana; Dayan, Gustavo H
Dengue is a viral disease usually transmitted by Aedes aegypti mosquitoes. Dengue outbreaks in the Americas reported in medical literature and to the Pan American Health Organization are described. The outbreak history from 1600 to 2010 was categorized into four phases: Introduction of dengue in the Americas (1600-1946); Continental plan for the eradication of the Ae. aegypti (1947-1970) marked by a successful eradication of the mosquito in 18 continental countries by 1962; Ae. aegypti reinfestation (1971-1999) caused by the failure of the mosquito eradication program; Increased dispersion of Ae. aegypti and dengue virus circulation (2000-2010) characterized by a marked increase in the number of outbreaks. During 2010 > 1.7 million dengue cases were reported, with 50,235 severe cases and 1,185 deaths. A dramatic increase in the number of outbreaks has been reported in recent years. Urgent global action is needed to avoid further disease spread.
Lubogo, Mutaawe; Donewell, Bangure; Godbless, Lucas; Shabani, Sasita; Maeda, Justin; Temba, Herilinda; Malibiche, Theophil C; Berhanu, Naod
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
Lubogo, Mutaawe; Donewell, Bangure; Godbless, Lucas; Shabani, Sasita; Maeda, Justin; Temba, Herilinda; Malibiche, Theophil C; Berhanu, Naod
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
Bond, Katherine C.; Macfarlane, Sarah B.; Burke, Charlanne; Ungchusak, Kumnuan; Wibulpolprasert, Suwit
We examine the emergence, development, and value of regional infectious disease surveillance networks that neighboring countries worldwide are organizing to control cross-border outbreaks at their source. The regional perspective represented in the paper is intended to serve as an instructive framework for others who decide to launch such networks as new technologies and emerging threats bring countries even closer together. Distinct from more formal networks in geographic regions designated by the World Health Organization (WHO), these networks usually involve groupings of fewer countries chosen by national governments to optimize surveillance efforts. Sometimes referred to as sub-regional, these “self-organizing” networks complement national and local government recognition with informal relationships across borders among epidemiologists, scientists, ministry officials, health workers, border officers, and community members. Their development over time reflects both incremental learning and growing connections among network actors; and changing disease patterns, with infectious disease threats shifting over time from local to regional to global levels. Not only has this regional disease surveillance network model expanded across the globe, it has also expanded from a mostly practitioner-based network model to one that covers training, capacity-building, and multidisciplinary research. Today, several of these networks are linked through Connecting Organizations for Regional Disease Surveillance (CORDS). We explore how regional disease surveillance networks add value to global disease detection and response by complementing other systems and efforts, by harnessing their power to achieve other goals such as health and human security, and by helping countries adapt to complex challenges via multi-sectoral solutions. We note that governmental commitment and trust among participating individuals are critical to the success of regional infectious disease
Baştuğ, Aliye; Bodur, Hürrem
Ebola virus disease (EVD) was defined first in 1976. Since then, more than 24 epidemics have been reported from Africa, predominantly with the Zaire species. On 21 March 2014, the current West Africa outbreak was reported by the World Health Organization, the largest one ever recorded. The Congo epidemic was reported in July 2014. It was considered that the two epidemics had unrelated origins with 96.8% identical genomic sequence of the virus. EVD outbreaks occurred in areas with limited resources but it has a potentially global effect due to the possibility of imported infection and the potential misuse of the virus as a bioweapon agent. Although EVD is a zoonotic disease with the reservoir of fruit bats, human-to-human transmission is essential in the spread of the infection. The case-fatality rate of EVD was reported as 70.8%. There is no approved prophylaxis, effective treatment, or licensed vaccine. Early diagnosis and isolation of the patients, contact tracing, appropriate use of personal protective equipment, and adherence to the guidance for safe funeral practices constitute the essential requirements to control the epidemics. This article provides a review of the literature regarding the characteristics and management of EVD outbreak.
Saito-Obata, Mariko; Saito, Mayuko; Tan, Titus C.; Medado, Inez Andrea P.; Dapat, Clyde; Okamoto, Michiko; Tamaki, Raita; Capistrano, Rowena C.; Segubre-Mercado, Edelwisa; Lupisan, Socorro P.; Oshitani, Hitoshi
Introduction: Typhoon Yolanda (Haiyan) hit the central part of the Philippines on November 8, 2013. To identify possible outbreaks of communicable diseases after the typhoon, nasopharyngeal swabs, stool and blood samples were collected from patients who visited the Eastern Visayas Regional Medical Center due to acute respiratory infection (ARI), acute gastroenteritis (AGE) or other febrile illness (OFI) including suspected dengue fever, between November 28, 2013 and February 5, 2014. Methods: Samples were tested on-site for selected pathogens using rapid diagnostic tests. Confirmation and further analysis were conducted at the Research Institute for Tropical Medicine (RITM) in Manila using polymerase chain reaction (PCR) and sequencing. Residues of the rapid diagnostic tests and samples collected in the filter papers (FTATM card) were transported to Manila under suboptimal conditions. PCR results were compared between the kit residues and the filter papers. Results: A total of 185 samples were collected. Of these, 128 cases were ARI, 17 cases were AGE and 40 cases were OFI. For nasopharyngeal swab samples, detection rates for enterovirus and rhinovirus residues were higher than the filter papers. For stool samples, rotavirus positive rate for the filter paper was higher than the kit residues. We also managed to obtain the sequence data from some of the kit residues and filter papers. Discussion: Our results confirmed the importance of PCR for the laboratory diagnosis of infectious diseases in post-disaster situations when diagnostic options are limited. PMID:27917305
Ahmadi, Elham; Pourbakhsh, Seyed Ali; Ahmadi, Malahat; Mardani, Karim; Talebi, Alireza
The northwest of Iran shares long borders with three neighboring countries; therefore, it is considered one of the main entry portals of Newcastle disease virus (NDV) into the country. Ten virulent NDVs were recovered from 19 poultry farms of various prefectures in northwestern Iran during Newcastle disease outbreaks in 2010. The isolates were genotypically analyzed using an F-gene-specific reverse transcription polymerase chain reaction (RT-PCR) assay. The amplified F gene (nucleotides 189-1666) sequences of the NDV isolates were compared phylogenetically with those of previously published strains in GenBank. All of the NDV isolates belonged to genotype VIIb and were closely related to some isolates from Iran, Russia, and Sweden. Therefore, it can be postulated that these isolates evolved from previously reported strains. The velogenic viruses carried the motif (112)R-R-Q-K-R/F(117) at the F0 cleavage site and a unique substitution of (190)L→F which had never been reported in any NDV genotype VIIb isolate. They shared high sequence similarity with each other but were distinct from current NDV vaccines and NDV strains reported from other countries. This information is fundamental for improving the efficacy of controlling strategies and vaccine development for NDV.
Sáfadi, Marco Aurelio Palazzi; Carvalhanas, Telma Regina Marques Pinto; Paula de Lemos, Ana; Gorla, Maria Cecilia Outeiro; Salgado, Maristela; Fukasawa, Lucila O; Gonçalves, Maria Gisele; Higa, Fabio; Brandileone, Maria Cristina Cunto; Sacchi, Claudio Tavares; Ribeiro, Ana Freitas; Sato, Helena Keico; Bricks, Lucia Ferro; Cassio de Moraes, José
During 2010, outbreaks of serogroup C meningococcal (MenC) disease occurred in 2 oil refineries in São Paulo State, Brazil, leading to mass vaccination of employees at 1 refinery with a meningococcal polysaccharide A/C vaccine. A cross-sectional study was conducted to assess the prevalence of meningococci carriage among workers at both refineries and to investigate the effect of vaccination on and the risk factors for pharyngeal carriage of meningococci. Among the vaccinated and nonvaccinated workers, rates of overall meningococci carriage (21.4% and 21.6%, respectively) and of MenC carriage (6.3% and 4.9%, respectively) were similar. However, a MenC strain belonging to the sequence type103 complex predominated and was responsible for the increased incidence of meningococcal disease in Brazil. A low education level was associated with higher risk of meningococci carriage. Polysaccharide vaccination did not affect carriage or interrupt transmission of the epidemic strain. These findings will help inform future vaccination strategies.
Catry, B; Duchateau, L; Van de Ven, J; Laevens, H; Opsomer, G; Haesebrouck, F; De Kruif, A
The efficacy of an injectable formulation of florfenicol (300 mg/mL) as metaphylactic control of naturally occurring bovine respiratory disease (BRD) was evaluated in two double-blind randomly controlled field studies on two Dutch veal calf herds (A and B). Cattle aged not older than 3 months and in the direct presence of calves with clinical respiratory disease were randomly allocated to treatment with 40 mg/kg florfenicol subcutaneously (s.c.) a positive control treatment (12.5 mg/kg tilmicosin p.o. twice daily for five consecutive days in herd A, and 12.5 mg/kg doxycycline p.o. twice daily for five consecutive days in herd B), or a negative control (one placebo saline s.c. administration on D0). The predominant respiratory pathogens present in pretreatment respiratory samples from affected animals were Mycoplasma bovis and Pasteurella multocida in outbreaks A and B, respectively. Metaphylactic administration of florfenicol resulted in a statistically significant weight gain, decreased rectal temperature for five consecutive days after treatment and decreased metaphylactic failure percentages compared with both positive and negative control groups. In summary, these studies demonstrated that a single s.c. injection of florfenicol is effective and practical for control of the bacterial component of BRD in veal calves.
Ladner, J T; Kuhn, J H; Palacios, G
Viral genome sequencing has become the cornerstone of almost all aspects of virology. In particular, high-throughput, next-generation viral genome sequencing has become an integral part of molecular epidemiological investigations into outbreaks of viral disease, such as the recent outbreaks of Middle Eastern respiratory syndrome, Ebola virus disease and Zika virus infection. Multiple institutes have acquired the expertise and necessary infrastructure to perform such investigations, as evidenced by the accumulation of thousands of novel viral sequences over progressively shorter time periods. The authors recently proposed a nomenclature comprised of five high-throughput sequencing standard categories to describe the quality of determined viral genome sequences. These five categories (standard draft, high quality, coding complete, complete and finished) cover all levels of viral genome finishing and can be applied to sequences determined by any technology platform or assembly technique.
Haga, Yuki; Kanda, Tatsuo; Sasaki, Reina; Nakamura, Masato; Nakamoto, Shingo; Yokosuka, Osamu
Nonalcoholic fatty liver disease (NAFLD) including nonalcoholic steatohepatitis (NASH) is globally increasing and has become a world-wide health problem. Chronic infection with hepatitis B virus or hepatitis C virus (HCV) is associated with hepatic steatosis. Viral hepatitis-associated hepatic steatosis is often caused by metabolic syndrome including obesity, type 2 diabetes mellitus and/or dyslipidemia. It has been reported that HCV genotype 3 exerts direct metabolic effects that lead to hepatic steatosis. In this review, the differences between NAFLD/NASH and viral hepatitis-associated steatosis are discussed.
Brown, Douglas (Sandia National Laboratories, Livermore, CA); Gray, Genetha Anne (Sandia National Laboratories, Livermore, CA)
Due to the nature of many infectious agents, such as anthrax, symptoms may either take several days to manifest or resemble those of less serious illnesses leading to misdiagnosis. Thus, bioterrorism attacks that include the release of such agents are particularly dangerous and potentially deadly. For this reason, a system is needed for the quick and correct identification of disease outbreaks. The Real-time Outbreak Disease Surveillance System (RODS), initially developed by Carnegie Mellon University and the University of Pittsburgh, was created to meet this need. The RODS software implements different classifiers for pertinent health surveillance data in order to determine whether or not an outbreak has occurred. In an effort to improve the capability of RODS at detecting outbreaks, we incorporate a data fusion method. Data fusion is used to improve the results of a single classification by combining the output of multiple classifiers. This paper documents the first stages of the development of a data fusion system that can combine the output of the classifiers included in RODS.
Information with regard to foot-and-mouth disease (FMD) outbreaks that occurred in the Kruger National Park (KNP) and adjacent areas of South Africa between 1970 and 2009 was collected from reports and files of various government departments and collated into one report. The collected data were summarised in a table and assessed for patterns. Fifty-one FMD outbreaks occurred during this period in the target area, of which 16 were SAT 1, 31 were SAT 2,4 were SAT 3 and 3 were not serotyped. No pattern could be discerned although SAT 1 outbreaks occurred more frequently in the summer months while more SAT 2 outbreaks occurred in winter.
Attaf, Meriem; Sewell, Andrew K
The importance of T-cell receptor (TCR) repertoire diversity is highlighted in murine models of immunodeficiency and in many human pathologies. However, the true extent of TCR diversity and how this diversity varies in health and disease is poorly understood. In a previous issue of the European Journal of Immunology, Lossius et al. [Eur. J. Immunol. 2014. 44: 3439-3452] dissected the composition of the TCR repertoire in the context of multiple sclerosis (MS) using high-throughput sequencing of TCR-β chains in cerebrospinal fluid samples and blood. The authors demonstrated that the TCR repertoire of the CSF was largely distinct from the blood and enriched in EBV-reactive CD8(+) T cells in MS patients. Studies of this kind have long been hindered by technical limitations and remain scarce in the literature. However, TCR sequencing methodologies are progressing apace and will undoubtedly shed light on the genetic basis of T-cell responses and the ontogeny of T-cell-mediated diseases, such as MS.
Eshofonie, Anthony O; Lin, Huai; Valcin, Randy P; Martin, LaTasha R; Grunenwald, Paul E
During 2012, an increase in the number of pertussis cases or outbreaks was reported among most states within the United States. The majority of these cases included previously vaccinated children between the ages of 7-10 years. This underscores the growing concern regarding current immunization practices and vaccine efficacy, especially as it pertains to pertussis prevention within this age group. In the fall of 2012, an outbreak of pertussis occurred within a school district in a rural Texas county that was reflective of this national pattern. Our objective is to describe this outbreak, highlight the similarities with the national trend, and identify strategies for better disease prevention. The cases in this outbreak were interviewed and laboratory testing done. Information regarding exposure and immunization history among cases was obtained. Immunization audits of the affected institutions were also conducted. We performed a descriptive analysis of the collected data using EPI-INFO software v.3.5.3. A total of 34 cases were identified in this outbreak, of which 23 were PCR confirmed and 11 were epidemiologically linked. Ages ranged from 5 months to 12 years, and 62 % were among children aged 7-10 years. All cases were up-to-date on their pertussis vaccinations. Immunization coverage rate was over 90 % within each of the affected institutions. The characteristics of this outbreak bear striking similarities to the current national trend in terms of age groups and immunization status of the affected cases. Increased focus on this vulnerable target group, including heightened scrutiny of vaccine efficacy and delivery, is indicated.
Gaze, Rosangela; Carvalho, Diana Maul de; Santoro-Lopes, Guilherme; Tura, Luiz Fernando Rangel
Viral hepatitis A, B, C, D and E--systemic hepatotropic viral infections--present as acute hepatitis that, depending on the etiological agent, viral load and host conditions, may evolve into chronic hepatitis, cirrhosis, liver cancer and acute fulminant disease. The ecological versatility of these viruses, their spectrum of transmission in time and space, potentialized by the sub-clinical course of a large proportion of infections, comprise an epidemiological challenge. This essay describes scenarios and tendencies in the socioepidemiologic profile, based on the history of these infections, and indicates the need to overcome patterns, models, and protocols and instead investigate each particular situation. In other words, it highlights the need to explore singularities in order to be able to develop new proposals for general actions tailored to local specificities.
Qin, Yao; Zheng, Shijun J
Infectious bursal disease (IBD) is an acute, highly contagious and immunosuppressive poultry disease caused by IBD virus (IBDV). The consequent immunosuppression increases susceptibility to other infectious diseases and the risk of subsequent vaccination failure as well. Since the genome of IBDV is relatively small, it has a limited number of proteins inhibiting the cellular antiviral responses and acting as destroyers to the host defense system. Thus, these virulence factors must be multifunctional in order to complete the viral replication cycle in a host cell. Insights into the roles of these viral proteins along with their multiple cellular targets in different pathways will give rise to a rational design for safer and effective vaccines. Here we summarize the recent findings that focus on the virus-cell interactions during IBDV infection at the protein level.
Qin, Yao; Zheng, Shijun J.
Infectious bursal disease (IBD) is an acute, highly contagious and immunosuppressive poultry disease caused by IBD virus (IBDV). The consequent immunosuppression increases susceptibility to other infectious diseases and the risk of subsequent vaccination failure as well. Since the genome of IBDV is relatively small, it has a limited number of proteins inhibiting the cellular antiviral responses and acting as destroyers to the host defense system. Thus, these virulence factors must be multifunctional in order to complete the viral replication cycle in a host cell. Insights into the roles of these viral proteins along with their multiple cellular targets in different pathways will give rise to a rational design for safer and effective vaccines. Here we summarize the recent findings that focus on the virus–cell interactions during IBDV infection at the protein level. PMID:28098808
MacLachlan, N James; Balasuriya, Udeni B; Davis, Nancy L; Collier, Martha; Johnston, Robert E; Ferraro, Gregory L; Guthrie, Alan J
Viral diseases constitute an ever growing threat to the horse industry worldwide because of the rapid movement of large numbers of horses for competition and breeding. A number of different types of vaccines are available for protective immunization of horses against viral diseases. Traditional inactivated and live-attenuated (modified live virus, MLV) virus vaccines remain popular and efficacious but recombinant vaccines are increasingly being developed and used, in part because of the perceived deficiencies of some existing products. New generation vaccines include MLVs with deletions and/or mutations of critical genes, subunit vaccines that incorporate immunogenic proteins (or portions thereof) or expression vectors that produce these proteins as immunogens, and DNA vaccines. New generation vaccines have been developed for several viral diseases of horses. We recently have developed an alphavirus replicon-vectored equine arteritis virus (EAV) vaccine, and evaluated a commercial canary pox virus-vectored vaccine for West Nile disease. The success of these new-generation vaccines has catalyzed efforts to develop improved vaccines for the prevention of African horse sickness, a disease of emerging global significance.
Gethmann, Jörn; Probst, Carolina; Sauter-Louis, Carola; Conraths, Franz Josef
Although there is a long tradition of research on animal disease control, economic evaluation of control measures is rather limited in veterinary medicine. This may, on the one hand, be due to the different types of costs and refunds and the different people and organizations bearing them, such as animal holders, county, region, state or European Union, but it may also be due to the fact that economic analyses are both complex and time consuming. Only recently attention has turned towards economic analysis in animal disease control. Examples include situations, when decisions between different control measures must be taken, especially if alternatives to culling or compulsory vaccination are under discussion. To determine an optimal combination of control measures (strategy), a cost-benefit analysis should be performed. It is not necessary to take decisions only based on the financial impact, but it becomes possible to take economic aspects into account. To this end, the costs caused by the animal disease and the adopted control measures must be assessed. This article presents a brief overview of the methodological approaches used to retrospectively analyse the economic impact of two particular relevant diseases in Germany in the last few years: Blue-tongue disease (BT) and Bovine Spongiform Encephalopathy (BSE).
Morton, S; Bartlett, C L; Bibby, L F; Hutchinson, D N; Dyer, J V; Dennis, P J
In September and October 1981 six cases of pneumonia occurred among men working in a power station under construction. Three were identified as cases of legionella pneumonia and two others had serology suggestive of legionella infection. In a sample of 92 men from the site 10 had low levels of antibodies to legionella; a similar sample of men working on an adjacent site showed none with positive serology. In a case control study it was found that cases of pneumonia were more likely than controls to have worked on a part of the site where four small capacity cooling towers were located. Legionella pneumophila serogroup 1 was isolated from the water systems of these four towers but was not found in samples from any other cooling towers or hot or cold water outlets on the site. It would appear that there was airborne spread of the organism from these cooling water systems which had not received conventional treatment to inhibit corrosion and organic growth. This is the first outbreak of legionnaires' disease to be recorded in an industrial setting in the United Kingdom. No cases of legionella infection have occurred on the site since the introduction of control measures. PMID:3756116
Thompson, D; Muriel, P; Russell, D; Osborne, P; Bromley, A; Rowland, M; Creigh-Tyte, S; Brown, C
The authors present estimates of the economic costs to agriculture and industries affected by tourism of the outbreak of foot and mouth disease (FMD) in the United Kingdom (UK) in 2001. The losses to agriculture and the food chain amount to about Pound Sterling3.1 billion. The majority of the costs to agriculture have been met by the Government through compensation for slaughter and disposal as well as clean-up costs. Nonetheless, agricultural producers will have suffered losses, estimated at Pound Sterling355 million, which represents about 20% of the estimated total income from farming in 2001. Based on data from surveys of tourism, businesses directly affected by tourist expenditure are estimated to have lost a similar total amount (between Pound Sterling2.7 and Pound Sterling3.2 billion) as a result of reduced numbers of people visiting the countryside. The industries which supply agriculture, the food industries and tourist-related businesses will also have suffered losses. However, the overall costs to the UK economy are substantially less than the sum of these components, as much of the expenditure by tourists was not lost, but merely displaced to other sectors of the economy. Overall, the net effect of FMD is estimated to have reduced the gross domestic product in the UK by less than 0.2% in 2001.
Rocchi, G.; Ragona, G.; Piga, C.; Pelosio, A.; Volpi, A.; Vella, S.; Legniti, N.; de Felici, A.
Immunization procedures with live attenuated and inactivated vaccines were carried out on a group of young recruits at the beginning of an outbreak of infection due to an A/Victoria/3/75-related virus strain, which occurred in February 1977 in a military camp. A retrospective investigation on protection from clinical influenza was then performed in order to investigate whether immunization with live virus vaccines, administered at the beginning of an epidemic, could provide early protection from the disease. In the course of the two weeks following vaccination, laboratory-confirmed clinical influenza cases occurred in 4 subjects among the 110 volunteers of the control group which received placebo, and in 8, 7 and 4 subjects respectively of the 3 groups of about 125 individuals, each of which received one of the following vaccine preparations: (a), live attenuated A/Victoria/3/75 influenza virus oral vaccine, grown on chick embryo kidney culture; (b), live attenuated nasal vaccine, a recombinant of A/Puerto Rico/8/34 with A/Victoria/3/75 virus; and (c), inactivated A/Victoria/3/75 virus intramuscular vaccine. These data do not support the hypothesis that, during an epidemic of infection, early protection from clinical influenza can be achieved through immunization with live attenuated or inactivated influenza virus vaccines, in spite of the high immunizing capability of the vaccine preparations. PMID:512351
Waldram, Alison; McKerr, Caoimhe; Gobin, Maya; Adak, Goutam; Stuart, James M; Cleary, Paul
Successful investigation of national outbreaks of communicable disease relies on rapid identification of the source. Case-control methodologies are commonly used to achieve this. We assessed control selection methods used in recently published case-control studies for methodological and resource issues to determine if a standard approach could be identified. Neighbourhood controls were the most frequently used method in 53 studies of a range of different sizes, infections and settings. The most commonly used method of data collection was face to face interview. Control selection issues were identified in four areas: method of identification of controls, appropriateness of controls, ease of recruitment of controls, and resource requirements. Potential biases arising from the method of control selection were identified in half of the studies assessed. There is a need to develop new ways of selecting controls in a rapid, random and representative manner to improve the accuracy and timeliness of epidemiological investigations and maximise the effectiveness of public health interventions. Innovative methods such as prior recruitment of controls could improve timeliness and representativeness of control selection.
Nguku, Patrick; Waziri, Ndadilnasiya; Adewuyi, Peter; Adeoye, Olawunmi; Adeseye, Aderonke; Oguntimehin, Olukayode; Shuaib, Faisal
The recent outbreak of Ebola Virus Disease (EVD) in West Africa has ravaged many lives. Effective containment of this outbreak relies on prompt and effective coordination and communication across various interventions; early detection and response being critical to successful control. The use of information and communications technology (ICT) in active surveillance has proved to be effective but its use in Ebola outbreak response has been limited. Due to the need for timeliness in reporting and communication for early discovery of new EVD cases and promptness in response; it became imperative to empower the response team members with technologies and solutions which would enable smooth and rapid data flow. The Open Data Kit and Form Hub technology were used in combination with the Dashboard technology and ArcGIS mapping for follow up of contacts, identification of cases, case investigation and management and also for strategic planning during the response. A remarkable improvement was recorded in the reporting of daily follow-up of contacts after the deployment of the integrated real time technology. The turnaround time between identification of symptomatic contacts and evacuation to the isolation facility and also for receipt of laboratory results was reduced and informed decisions could be taken by all concerned. Accountability in contact tracing was ensured by the use of a GPS enabled device. The use of innovative technologies in the response of the EVD outbreak in Nigeria contributed significantly to the prompt control of the outbreak and containment of the disease by providing a valuable platform for early warning and guiding early actions. PMID:26115402
Goens, S Denise
The economic importance of bovine viral diarrhea is increasing with the emergence of seemingly more virulent viruses, as evidenced by outbreaks of hemorrhagic syndrome and severe acute bovine viral diarrhea beginning in the 1980s and 1990s. It appears that evolutionary changes in bovine viral diarrhea virus were responsible for these outbreaks. The genetic properties of the classical bovine viral diarrhea virus that contribute to the basis of current diagnostic tests, vaccines, and our understanding of pathogenic mechanisms are now being reevaluated because of these "new" virus strains. This shift in virulence has confounded both nomenclature and the significance of current bovine viral diarrhea virus categorization. The purpose of this review is to summarize our current understanding of bovine viral diarrhea virus with a chronological review of prevailing scientific tenets and practices as described in clinical and scientific North American veterinary journals and textbooks. The first part of this review describes how we have arrived at our current understanding of the viruses, the diseases, and their nomenclature. The second part of the review deals with current concepts in virology and how these concepts may both explain and predict bovine viral diarrhea virus pathogenesis. By reviewing how knowledge of bovine viral diarrhea has evolved and the theories of how the virus itself is able to evolve, the interpretation of diagnostic tests are more effectively utilized in the control and treatment of bovine viral diarrhea virus associated disease.
Bekolo, Cavin Epie; van Loenhout, Joris Adriaan Frank; Rodriguez-Llanes, Jose Manuel; Rumunu, John; Ramadan, Otim Patrick
Abstract Objective To determine whether pre-emptive oral cholera vaccination reduces disease severity and mortality in people who develop cholera disease during an outbreak. Methods The study involved a retrospective analysis of demographic and clinical data from 41 cholera treatment facilities in South Sudan on patients who developed cholera disease between 23 April and 20 July 2014 during a large outbreak, a few months after a pre-emptive oral vaccination campaign. Patients who developed severe dehydration were regarded as having a severe cholera infection. Vaccinated and unvaccinated patients were compared and multivariate logistic regression analysis was used to identify factors associated with developing severe disease or death. Findings In total, 4115 cholera patients were treated at the 41 facilities: 1946 (47.3%) had severe disease and 62 (1.5%) deaths occurred. Multivariate analysis showed that patients who received two doses of oral cholera vaccine were 4.5-fold less likely to develop severe disease than unvaccinated patients (adjusted odds ratio, aOR: 0.22; 95% confidence interval, CI: 0.11–0.44). Moreover, those with severe cholera were significantly more likely to die than those without (aOR: 4.76; 95% CI: 2.33–9.77). Conclusion Pre-emptive vaccination with two doses of oral cholera vaccine was associated with a significant reduction in the likelihood of developing severe cholera disease during an outbreak in South Sudan. Moreover, severe disease was the strongest predictor of death. Two doses of oral cholera vaccine should be used in emergencies to reduce the disease burden. PMID:27708472
Lin, Yeou-Liang; Chang, Chia-Yi; Pan, Chu-Hsiang; Deng, Ming-Chung; Tsai, Hsiang-Jung; Lee, Fan
Foot-and-mouth disease virus, a member of genus Aphthovirus within the family Picornaviridae, affects cloven-hoofed animals, causing foot-and-mouth disease characterized by vesicle development. The Southeast Asia topotype, one of the topotypes within serotype O of the virus, is prevalent in some Asian countries, but had not previously been found in Taiwan. The topotype was first found in pigs in Kinmen Island, Taiwan, in 2012 and identified by nucleotide sequence comparison and phylogenetic analysis. Outbreaks were reported at 4 farms, resulting in the culling of 628 pigs and 1 cattle. Pigs were the only species infected during the outbreak. The incursion of Southeast Asia topotype into Taiwan implies the expansion of the topotype in East Asia.
LIN, Yeou-Liang; CHANG, Chia-Yi; PAN, Chu-Hsiang; DENG, Ming-Chung; TSAI, Hsiang-Jung; LEE, Fan
ABSTRACT Foot-and-mouth disease virus, a member of genus Aphthovirus within the family Picornaviridae, affects cloven-hoofed animals, causing foot-and-mouth disease characterized by vesicle development. The Southeast Asia topotype, one of the topotypes within serotype O of the virus, is prevalent in some Asian countries, but had not previously been found in Taiwan. The topotype was first found in pigs in Kinmen Island, Taiwan, in 2012 and identified by nucleotide sequence comparison and phylogenetic analysis. Outbreaks were reported at 4 farms, resulting in the culling of 628 pigs and 1 cattle. Pigs were the only species infected during the outbreak. The incursion of Southeast Asia topotype into Taiwan implies the expansion of the topotype in East Asia. PMID:25056674
Fonnesbeck, C.J.; Dodd, C.K.
We estimated survivorship, recapture probabilities and recovery rates in a threatened population of Flattened Musk Turtles (Sternotherus depressus) through a disease outbreak in Alabama in 1985. We evaluated a set of models for the demographic effects of disease by analyzing recaptures and recoveries simultaneously. Multiple-model inference suggested survival was temporally dynamic, whereas recapture probability was sex- and age-specifc. Biweekly survivorship declined from 98-99% before to 82-88% during the outbreak. Live recapture was twice as likely for male turtles relative to juveniles or females, whereas dead recoveries varied only slightly by sex and age. Our results suggest modest reduction in survival over a relatively short time period may severely affect population status.
McLaws, Melissa; Ribble, Carl
The objective of this investigation was to describe the detection of foot and mouth disease (FMD) outbreaks in nonendemic areas, and to consider how events early in an epidemic influence the epidemic’s course. We identified 24 epidemics that occurred between 1992 and 2003 in areas officially considered free of FMD. We obtained information about these epidemics from many sources, including the scientific literature, the grey (non peer-reviewed) literature, and individuals involved with the outbreaks. While most of the epidemics consisted of fewer than 150 infected premises, there were 4 extremely large epidemics, each consisting of more than 2000 infected premises. There was no direct relationship between the time to detection and either the total number of infected premises or the number of animals killed for disease control purposes. We believe that the movement of infected animals through markets was the most critical factor that contributed to the unusual magnitude of the very large epidemics. PMID:17987967
Stott, A W; Humphry, R W; Gunn, G J
A previously published model was re-employed to examine the potential impact of different epidemiological circumstances on output losses due to bovine viral diarrhoea virus (BVDV) infection in typical British hill cow-calf enterprises. The average annuity equivalent of unchecked losses from 100 simulated 10-year disease scenarios ranged from almost pound0/cow to approximately pound40/cow. Significant differences were found under certain circumstances, depending on the initial disease status of the herd, the initial source of virus, the probability and source of further infection, the probability of virus transmission within the herd and herd size. For naïve herds, losses depended only on the risk of incursion. In most other circumstances, the losses could be mitigated if the annual risk of incursion was <0.3 and risk of within herd transmission was extremely low. Greater understanding of the interaction between these risk factors and management actions are required so that total costs of BVDV infection can be minimised under different circumstances.
Owada, Kei; Eckmanns, Tim; Kamara, Kande-Bure O'Bai; Olu, Olushayo Oluseun
Sierra Leone experienced intense transmission of Ebola virus disease (EVD) from May 2014 to November 2015 during which a total of 8,704 confirmed cases and over 3,589 confirmed deaths were reported. Our field observation showed many issues in the EVD data management system, which may have contributed to the magnitude and long duration of the outbreak. In this perspective article, we explain the key issues with EVD data management in the field, and the resulting obstacles in analyzing key epidemiological indicators during the outbreak response work. Our observation showed that, during the latter part of the EVD outbreak, surveillance and data management improved at all levels in the country as compared to the earlier stage. We identified incomplete filling and late arrival of the case investigation forms at data management centers, difficulties in detecting double entries and merging identified double entries in the database, and lack of clear process of how death of confirmed cases in holding, treatment, and community care centers are reported to the data centers as some of challenges to effective data management. Furthermore, there was no consolidated database that captured and linked all data sources in a structured way. We propose development of a new application tool easily adaptable to new occurrences, regular data harmonization meetings between national and district data management teams, and establishment of a data quality audit system to assure good quality data as ways to improve EVD data management during future outbreaks.
Owada, Kei; Eckmanns, Tim; Kamara, Kande-Bure O’Bai; Olu, Olushayo Oluseun
Sierra Leone experienced intense transmission of Ebola virus disease (EVD) from May 2014 to November 2015 during which a total of 8,704 confirmed cases and over 3,589 confirmed deaths were reported. Our field observation showed many issues in the EVD data management system, which may have contributed to the magnitude and long duration of the outbreak. In this perspective article, we explain the key issues with EVD data management in the field, and the resulting obstacles in analyzing key epidemiological indicators during the outbreak response work. Our observation showed that, during the latter part of the EVD outbreak, surveillance and data management improved at all levels in the country as compared to the earlier stage. We identified incomplete filling and late arrival of the case investigation forms at data management centers, difficulties in detecting double entries and merging identified double entries in the database, and lack of clear process of how death of confirmed cases in holding, treatment, and community care centers are reported to the data centers as some of challenges to effective data management. Furthermore, there was no consolidated database that captured and linked all data sources in a structured way. We propose development of a new application tool easily adaptable to new occurrences, regular data harmonization meetings between national and district data management teams, and establishment of a data quality audit system to assure good quality data as ways to improve EVD data management during future outbreaks. PMID:27551675
2012 24-Mar-2014 Approved for Public Release; Distribution Unlimited Research Area 7.4:Identifying a Path Towards Rapid Discrimination of Infection ...Identifying a Path Towards Rapid Discrimination of Infection Disease Outbreaks Report Title The low cost and relative ease of obtaining, producing, and...MRSA is a bacterium responsible for several difficult-to-treat infections in humans. Metagenomics: The study of metagenomes, or DNA collected
Hubálek, Z.; Halouzka, J.
West Nile virus causes sporadic cases and outbreaks of human and equine disease in Europe (western Mediterranean and southern Russia in 1962-64, Belarus and Ukraine in the 1970s and 1980s, Romania in 1996-97, Czechland in 1997, and Italy in 1998). Environmental factors, including human activities, that enhance population densities of vector mosquitoes (heavy rains followed by floods, irrigation, higher than usual temperature, or formation of ecologic niches that enable mass breeding of mosquitoes) could increase the incidence of West Nile fever. PMID:10511520
Barão Da Cunha, M; Correia, J J; Fagulha, T; Fevereiro, M; Peleteiro, M C; Vollrath, G; Kaleta, E F
The Lisbon's Zoological Garden, Portugal, has maintained for many years a large collection of psittacine birds without any serious health problems. Unexpectedly, in April 1999, a total of nine macaws died after a short period of illness. Clinical signs consisted mainly of anorexia, ruffled feathers and yellowish droppings. A herpesvirus was isolated from brain, trachea, lung, liver, spleen, kidney and intestine of each of the examined dead birds, confirming that all animals succumbed during viraemia. Serotyping of the isolate in cross neutralization tests with reference sera prove that the outbreak was caused by serotype 3 of Pacheco's parrot disease herpesviruses. An autogenous, formalin-inactivated vaccine with adjuvant (aluminium hydroxid gel) was prepared from one of the isolates and injected intramuscularly 14 days and six weeks after the onset of mortality in an attempt to protect the remaining psittacine birds in the zoo from the disease. The autogenous vaccine was well tolerated and was able to rapidly stop virus spread and morbidity and mortality among the psittacine birds. Follow-up studies demonstrate that all nine blood samples from vaccinated birds obtained nine month' after the second vaccination contain neutralizing antibodies. Twenty five month' after vaccination two out of four serum samples were still antibody positive. No herpesvirus was isolated from faecal samples nine and twenty five months after the onset of the outbreak. These data prove that the autogenous vaccine played a major role in containing a severe outbreak of Pacheco's parrot disease in a large collection of psittacine birds.
Meyers, Linda; Frawley, Thomas; Goss, Sarah; Kang, Christopher
The 2014 Ebola outbreak in West Africa is the largest in history. Ebola viral disease is a severe and fatal illness characterized by a nonspecific viral syndrome followed by fulminant septic shock and coagulopathy. Despite ongoing efforts directed at experimental treatments and vaccine development, current medical management of Ebola viral disease is largely limited to supportive therapy, thus making early case identification and immediate implementation of appropriate control measures critical. Because a case of Ebola viral disease was confirmed in the United States on September 30, 2014, emergency medicine providers should be knowledgeable about it for a number of reasons: we are being called on to answer questions about Ebola and allay public fears, we are likely to be first to encounter an infected patient, and there are increasing numbers of US emergency physicians working in Africa who risk coming in direct contact with the disease. This article seeks to provide emergency physicians with the essential and up-to-date information required to identify, evaluate, and manage Ebola viral disease and to join global efforts to contain the current outbreak.
Kumar, Tripurari; Shrivastava, Aakash; Kumar, Anil; Laserson, Kayla F; Narain, Jai P; Venkatesh, Srinivasaraghavan; Chauhan, Lakhbir S; Averhoff, Francisco
The burden of viral hepatitis in India is not well characterized. In 2009, the national Integrated Disease Surveillance Programme (IDSP) began conducting surveillance across all Indian states for epidemic-prone diseases, including foodborne and waterborne forms of viral hepatitis (e.g., hepatitis A and E). Information on outbreaks of all forms of viral hepatitis, including A, B, C, and E, also is collected. This report summarizes viral hepatitis surveillance and outbreak data reported to IDSP during 2011-2013. During this period, 804,782 hepatitis cases and 291 outbreaks were reported; the virus type was unspecified in 92% of cases. Among 599,605 cases tested for hepatitis A, 44,663 (7.4%) were positive, and among 187,040 tested for hepatitis E, 19,508 (10.4%) were positive. At least one hepatitis outbreak report was received from 23 (66%) of 35 Indian states. Two-thirds of outbreaks were reported from rural areas. Among 163 (56%) outbreaks with known etiology, 78 (48%) were caused by hepatitis E, 54 (33%) by hepatitis A, 19 (12%) by both hepatitis A and E, and 12 (7%) by hepatitis B or hepatitis C. Contaminated drinking water was the source of most outbreaks. Improvements in water quality and sanitation as well as inclusion of hepatitis A vaccine in childhood immunization programs should be considered to reduce the public health burden of hepatitis in India. Efforts to decrease the proportion of cases for which the etiology is unspecified, including expanding the IDSP to support hepatitis B and C testing, might help further elucidate the epidemiology of these diseases.
Aeby, Greta S.; Work, Thierry M.; Runyon, Christina M.; Shore-Maggio, Amanda; Ushijima, Blake; Videau, Patrick; Beurmann, Silvia; Callahan, Sean M.
A high number of coral colonies, Montipora spp., with progressive tissue loss were reported from the north shore of Kaua‘i by a member of the Eyes of the Reef volunteer reporting network. The disease has a distinct lesion (semi-circular pattern of tissue loss with an adjacent dark band) that was first observed in Hanalei Bay, Kaua‘i in 2004. The disease, initially termedMontipora banded tissue loss, appeared grossly similar to black band disease (BBD), which affects corals worldwide. Following the initial report, a rapid response was initiated as outlined in Hawai‘i’s rapid response contingency plan to determine outbreak status and investigate the disease. Our study identified the three dominant bacterial constituents indicative of BBD (filamentous cyanobacteria, sulfate-reducing bacteria, sulfide-oxidizing bacteria) in coral disease lesions from Kaua‘i, which provided the first evidence of BBD in the Hawaiian archipelago. A rapid survey at the alleged outbreak site found disease to affect 6-7% of the montiporids, which is higher than a prior prevalence of less than 1% measured on Kaua‘i in 2004, indicative of an epizootic. Tagged colonies with BBD had an average rate of tissue loss of 5.7 cm2/day over a two-month period. Treatment of diseased colonies with a double band of marine epoxy, mixed with chlorine powder, effectively reduced colony mortality. Within two months, treated colonies lost an average of 30% less tissue compared to untreated controls.
Aeby, Greta S.; Work, Thierry M.; Runyon, Christina M.; Shore-Maggio, Amanda; Ushijima, Blake; Videau, Patrick; Beurmann, Silvia; Callahan, Sean M.
A high number of coral colonies, Montipora spp., with progressive tissue loss were reported from the north shore of Kaua‘i by a member of the Eyes of the Reef volunteer reporting network. The disease has a distinct lesion (semi-circular pattern of tissue loss with an adjacent dark band) that was first observed in Hanalei Bay, Kaua‘i in 2004. The disease, initially termed Montipora banded tissue loss, appeared grossly similar to black band disease (BBD), which affects corals worldwide. Following the initial report, a rapid response was initiated as outlined in Hawai‘i’s rapid response contingency plan to determine outbreak status and investigate the disease. Our study identified the three dominant bacterial constituents indicative of BBD (filamentous cyanobacteria, sulfate-reducing bacteria, sulfide-oxidizing bacteria) in coral disease lesions from Kaua‘i, which provided the first evidence of BBD in the Hawaiian archipelago. A rapid survey at the alleged outbreak site found disease to affect 6-7% of the montiporids, which is higher than a prior prevalence of less than 1% measured on Kaua‘i in 2004, indicative of an epizootic. Tagged colonies with BBD had an average rate of tissue loss of 5.7 cm2/day over a two-month period. Treatment of diseased colonies with a double band of marine epoxy, mixed with chlorine powder, effectively reduced colony mortality. Within two months, treated colonies lost an average of 30% less tissue compared to untreated controls. PMID:25774800
Ansumana, Rashid; Keitell, Samuel; Roberts, Gregory M T; Ntoumi, Francine; Petersen, Eskild; Ippolito, Giuseppe; Zumla, Alimuddin
The World Health Organization (WHO) Global Tuberculosis Report 2015 states that 28% of the world's 9.6 million new tuberculosis (TB) cases are in the WHO Africa Region. The Mano River Union (MRU) countries of West Africa-Guinea, Sierra Leone, and Liberia-have made incremental sustained investments into TB control programmes over the past two decades. The devastating Ebola virus disease (EVD) outbreak of 2014-2015 in West Africa impacted significantly on all sectors of the healthcare systems in the MRU countries, including the TB prevention and control programmes. The EVD outbreak also had an adverse impact on the healthcare workforce and healthcare service delivery. At the height of the EVD outbreak, numerous staff members in all MRU countries contracted EBV at the Ebola treatment units and died. Many healthcare workers were also infected in healthcare facilities that were not Ebola treatment units but were national hospitals and peripheral health units that were unprepared for receiving patients with EVD. In all three MRU countries, the disruption to TB services due to the EVD epidemic will no doubt have increased Mycobacterium tuberculosis transmission, TB morbidity and mortality, and decreased patient adherence to TB treatment, and the likely impact will not be known for several years to come. In this viewpoint, the impact that the EVD outbreak had on TB diagnostic, management, and prevention services is described. Vaccination against TB with BCG in children under 5 years of age was affected adversely by the EVD epidemic. The EVD outbreak was a result of global failure and represents yet another 'wake-up call' to the international community, and particularly to African governments, to reach a consensus on new ways of thinking at the national, regional, and global levels for building healthcare systems that can sustain their function during outbreaks. This is necessary so that other disease control programmes (like those for TB, malaria, and HIV) are not
Diseases and Conditions Viral gastroenteritis (stomach flu) By Mayo Clinic Staff Viral gastroenteritis is an intestinal infection marked by watery diarrhea, abdominal cramps, nausea or vomiting, and ...
Aeby, Greta S.; Callahan, Sean; Cox, Evelyn F.; Runyon, Christina M.; Smith, Ashley; Stanton, Frank G.; Ushijima, Blake; Work, Thierry M.
In March 2010 and January 2012, we documented 2 widespread and severe coral disease outbreaks on reefs throughout Kāne‘ohe Bay, Hawai‘i (USA). The disease, acute Montipora white syndrome (aMWS), manifested as acute and progressive tissue loss on the common reef coral M. capitata. Rapid visual surveys in 2010 revealed 338 aMWS-affected M. capitata colonies with a disease abundance of (mean ± SE) 0.02 ± 0.01 affected colonies per m of reef surveyed. In 2012, disease abundance was significantly higher (1232 aMWS-affected colonies) with 0.06 ± 0.02 affected colonies m-1. Prior surveys found few acute tissue loss lesions in M. capitata in Kāne‘ohe Bay; thus, the high number of infected colonies found during these outbreaks would classify this as an emerging disease. Disease abundance was highest in the semi-enclosed region of south Kāne‘ohe Bay, which has a history of nutrient and sediment impacts from terrestrial runoff and stream discharge. In 2010, tagged colonies showed an average tissue loss of 24% after 1 mo, and 92% of the colonies continued to lose tissue in the subsequent month but at a slower rate (chronic tissue loss). The host-specific nature of this disease (affecting only M. capitata) and the apparent spread of lesions between M. capitatacolonies in the field suggest a potential transmissible agent. The synchronous appearance of affected colonies on multiple reefs across Kāne‘ohe Bay suggests a common underlying factor. Both outbreaks occurred during the colder, rainy winter months, and thus it is likely that some parameter(s) associated with winter environmental conditions are linked to the emergence of disease outbreaks on these reefs.
In 1999, in Toledo, Ohio, an outbreak of gastroenteritis occurred among people who had attended a Christmas dinner banquet and had eaten food prepared by a local caterer. Overall, 93 of the 137 attendees (67.9 percent) reported illness. Eight sought medical care, and one was hospitalized. Case-control studies revealed that the illness was associated with eating tossed salad (odds ratio [OR] = 2.5, 95 percent confidence interval [CI] = 1.02-6.26). Eleven of 12 stool specimens that were taken from ill people tested positive for a Norwalk-like virus (NLV) but were negative for E. coli O157:H7, Salmonella, and Shigella. The primary source of the outbreak was not determined, but an infected food handler may have played a role in the transmission of the virus. The catering facility had been cited frequently for food safety and hygiene violations. None of the personnel or food handlers at this facility had been appropriately trained in safe food-handling practices, nor had the personnel at another local caterer that had prepared food items suspected of causing a multistate outbreak of NLVs. In Toledo, food service operations with trained personnel/food handlers received better inspection reports than food service operations without trained personnel and were less likely to contribute to foodborne outbreaks. Training of personnel and food handlers may be important for preventing outbreaks.
There is growing concern in Sub-Saharan Africa about the spread of the Ebola virus disease (EVD), formerly known as Ebola haemorrhagic fever, and the public health burden that it ensues. Since 1976, there have been 885,343 suspected and laboratory confirmed cases of EVD and the disease has claimed 2,512 cases and 932 fatality in West Africa. There are certain requirements that must be met when responding to EVD outbreaks and this process could incur certain challenges. For the purposes of this paper, five have been identified: (i) the deficiency in the development and implementation of surveillance response systems against Ebola and others infectious disease outbreaks in Africa; (ii) the lack of education and knowledge resulting in an EVD outbreak triggering panic, anxiety, psychosocial trauma, isolation and dignity impounding, stigmatisation, community ostracism and resistance to associated socio-ecological and public health consequences; (iii) limited financial resources, human technical capacity and weak community and national health system operational plans for prevention and control responses, practices and management; (iv) inadequate leadership and coordination; and (v) the lack of development of new strategies, tools and approaches, such as improved diagnostics and novel therapies including vaccines which can assist in preventing, controlling and containing Ebola outbreaks as well as the spread of the disease. Hence, there is an urgent need to develop and implement an active early warning alert and surveillance response system for outbreak response and control of emerging infectious diseases. Understanding the unending risks of transmission dynamics and resurgence is essential in implementing rapid effective response interventions tailored to specific local settings and contexts. Therefore, the following actions are recommended: (i) national and regional inter-sectorial and trans-disciplinary surveillance response systems that include early warnings, as well
Ahmadivand, Sohrab; Soltani, Mehdi; Mardani, Karim; Shokrpoor, Sara; Hassanzadeh, Reza; Ahmadpoor, Mehran; Rahmati-Holasoo, Hooman; Meshkini, Saeid
Infectious hematopoietic necrosis virus (IHNV) is the etiological agent of a contagious disease (IHN) mainly in salmonid fish. In the present study, we isolated and identified IHNV in trout fry from Iranian trout farms with unexplained high mortality in 2016. The affected fry showed cumulative mortality of 90% with the gross pathological signs including exophthalmia and hemorrhage of the eye, skin darkening, abdominal distension, ulceration of the snout, and the visceral pallor and yellowish fluid in the intestine. Histopathological examination revealed marked necrosis in the anterior kidney, liver and spleen with the intracytoplasmic inclusion bodies in the liver sections. Also, intranuclear inclusion body and marginated chromatin were observable in the hematopoietic cells of the kidney. The homogenates tissues of infected fry induced IHNV-positive cytopathic effects (CPE) in EPC cells and confirmed by RT-PCR reactions and sequencing. Phylogenetic analysis revealed the Iranian IHNV isolates belonged to the European (E) genogroup with 100% identity to some Italian isolates. This is the first report of IHNV infection in farmed trout fry in Iran describing the viral isolation, clinical symptoms, histopathological findings, molecular confirmation, and genetic analysis suggestion of the specific country of origin.
Gossner, C M; de Jong, B; Hoebe, C J; Coulombier, D
During 2008 to 2013, 215 outbreak alerts, also known as 'urgent inquiries' (UI), for food- and waterborne diseases were launched in Europe, the majority of them (135; 63%) being related to salmonellosis. For 110 (51%) UI, a potential food vehicle of infection was identified, with vegetables being the most reported category (34;31%). A total of 28% (n = 60) of the outbreaks reported had an international dimension, involving at least two countries (mean: 4; standard deviation: 2; range:2–14). Participating countries posted 2,343 messages(initial posts and replies, excluding updates), with a median of 11 messages per urgent inquiry (range:1–28). Of 60 multicountry UI, 50 involved between two and four countries. The UI allowed early detection of multicountry outbreaks, facilitated the identification of the suspected vehicles and consequently contributed to the timely implementation of control measures. The introduction of an epidemic intelligence information system platform in 2010 has strengthened the role of the Food- and Waterborne Diseases and Zoonoses network in facilitating timely exchange of information between public health authorities of the participating countries.
Speed, B R; Gerrard, M P; Kennett, M L; Catton, M G; Harvey, B M
In developing countries, the major outbreaks of viral haemorrhagic fevers such as Marburg, Ebola and Lassa fever viruses have been nosocomially spread. The high mortality and absence of specific treatment have had a devastating effect. Epidemics of this highly contagious disease remain a constant threat to Australia and, as a result, carefully planned laboratory and public health strategies and clinical infection control measures have been instituted for the management of suspected cases.
Changula, Katendi; Kajihara, Masahiro; Mweene, Aaron S; Takada, Ayato
Filoviral hemorrhagic fever (FHF) is caused by ebolaviruses and marburgviruses, which both belong to the family Filoviridae. Egyptian fruit bats (Rousettus aegyptiacus) are the most likely natural reservoir for marburgviruses and entry into caves and mines that they stay in has often been associated with outbreaks of MVD. On the other hand, the natural reservoir for ebola viruses remains elusive; however, handling of wild animal carcasses has been associated with some outbreaks of EVD. In the last two decades, there has been an increase in the incidence of FHF outbreaks in Africa, some being caused by a newly found virus and some occurring in previously unaffected areas such as Guinea, Liberia and Sierra Leone, in which the most recent EVD outbreak occurred in 2014. Indeed, the predicted geographic distribution of filoviruses and their potential reservoirs in Africa includes many countries in which FHF has not been reported. To minimize the risk of virus dissemination in previously unaffected areas, there is a need for increased investment in health infrastructure in African countries, policies to facilitate collaboration between health authorities from different countries, implementation of outbreak control measures by relevant multi-disciplinary teams and education of the populations at risk.
Peton, M; Vilain, P; Reilhes, O; Cardinale, E; Gaüzère, B A; Filleul, L
In Reunion Island, the risk of emerging infectious diseases lies mainly in several viral zoonoses: West Nile fever, Sindbis virus, Nipah virus, Wesselsbron virus, Rift Valley fever and Japanese encephalitis. There morbidity and consequences are more or less important but they all have a non-negligible epidemic potential, so they have to be monitored. Indeed, the struggle against these emerging infectious diseases requires an early detection of the cases, thus a surveillance system capable of detecting them as early as possible, thanks to a real international network of information, warning and prevention.
Itsathitphaisarn, Ornchuma; Thitamadee, Siripong; Weerachatyanukul, Wattana; Sritunyalucksana, Kallaya
Viral pathogens pose a primary threat to global shrimp aquaculture. Despite the urgent industry need for them, practical anti-viral control methods are unavailable due, in part, to lack of an adaptive immune response in crustaceans that renders conventional vaccination methods ineffective. One currently studied method of high interest for protecting shrimp against viral infection relies on the post-transcriptional gene silencing mechanism called RNA interference (RNAi) that is induced by gene-specific constructs of double stranded RNA (dsRNA). Although this approach was first described for successful protection of shrimp against white spot disease (WSD) by injecting dsRNA specific to genes of white spot syndrome virus (WSSV) into shrimp in the laboratory in 2005 no practical method for use of dsRNA in shrimp farms has been developed to date. The apparent bottleneck for farm-scale applications of RNAi-mediated viral control in shrimp aquaculture is the lack of simple and cost-effective delivery methods. This review summarizes recent studies on use and delivery of dsRNA to shrimp via injection and oral routes in hatcheries and on farms and it discusses the research directions that might lead to development of practical methods for applications with farmed shrimp. Oral delivery methods tested so far include use of dsRNA-expressing bacteria as a component of dry feed pellets or use of living brine shrimp (Artemia) pre-fed with dsRNA before they are fed to shrimp. Also tested have been dsRNA enclosed in nanocontainers including chitosan, liposomes and viral-like particles (VLP) before direct injection or use as components of feed pellets for hatchery or pond-reared shrimp.
Jesus, Hiane Santos de; Nascimento, Gilmara Lima; Rosa, Fabiano Marques; Santos, Deise Aparecida dos
In July 27th, 2010, witnessed the late notification of a positive test result for measles IgM antibodies in Belém, Pará State, Brazil, sparking an epidemiological investigation and control and preventive measures. Two more confirmed cases were identified, both of whom were siblings of the index case, with clinical signs and symptoms and incubation period consistent with measles. We conducted a retrospective search in hospitals and laboratories for suspected cases that lived in or had visited Pará State from May 1st to August 4th, 2010, and had presented fever and exanthema accompanied by cough and/or sneezing and/or conjunctivitis. All identified cases were investigated by telephone contact and/or home visits. We reviewed 183,854 consultation forms and identified 56 (0.03%) suspected cases. We applied 2,535 doses of triple viral vaccine distributed between blockades vaccination intensifications. A household measles outbreak occurred in Belém with the detection and isolation of a viral genotype imported from Europe. Timely and sensitive epidemiological surveillance is recommended for the detection of suspected cases of measles and maintenance of high immunization coverage.
Squires, R A
Viruses commonly cause gastrointestinal illnesses in dogs and cats that range in severity from mild diarrhoea to malignant neoplasia. Perpetual evolution of viruses is reflected in changing disease patterns, so that familiar viruses are sometimes discovered to cause new or unexpected diseases. For example, canine parvovirus (CPV) has regained the ability to infect felids and cause a panleucopenia-like illness. Feline panleucopenia virus (FPV) has been shown to cause fading in young kittens and has recently been implicated as a possible cause of feline idiopathic cardiomyopathy. Molecular scrutiny of viral diseases sometimes permits deeper understanding of pathogenesis and epizootiology. Feline gastrointestinal lymphomas have not, in the past, been strongly associated with retroviral infections, yet some of these tumours harbour retroviral proviruses. Feline leukaemia virus (FeLV) may play a role in lymphomagenesis, even in cats diagnosed as uninfected using conventional criteria. There is strong evidence that feline immunodeficiency virus (FIV) can also be oncogenic. The variant feline coronaviruses that cause invariably-fatal feline infectious peritonitis (FIP) arise by sporadic mutation of an ubiquitous and only mildly pathogenic feline enteric coronavirus (FECV); a finding that has substantial management implications for cat breeders and veterinarians. Conversely, canine enteric coronavirus (CECV) shows considerable genetic and antigenic diversity but causes only mild, self-limiting diarrhoea in puppies. Routine vaccination against this virus is not recommended. Although parvoviruses, coronaviruses and retroviruses are the most important known viral causes of canine and feline gastrointestinal disease, other viruses play a role. Feline and canine rotaviruses have combined with human rotaviruses to produce new, reassortant, zoonotic viruses. Some companion animal rotaviruses can infect humans directly. Undoubtedly, further viral causes of canine and feline
Gunn, G J; Stott, A W; Humphry, R W
Results from an epidemiological model of an outbreak of Bovine Viral Diarrhoea (BVD) within a Scottish beef suckler herd are presented. These results concurred with field observations and encouraged us to fulfill the objective of providing an estimate of losses due to BVD to assist decision makers. Using the output from the model, estimates were made of losses associated with the outbreak. Without taking into account any financial premiums associated with disease-free status, the estimate of pound 37 (58) mean loss per cow per annum suggests that health schemes and vaccination should be of immediate financial interest to farmers and veterinary advisors.
Sasaki, Takashi; Matsumoto, Nobuhiro; Nakao, Hiroyuki; Katoh, Takahiko; Fukuda, Yusuke; Nakazato, Masamitsu; Okayama, Akihiko
Few reports have analyzed the clinical manifestations of patients with Legionnaires' disease in large outbreaks throughout the world. We retrospectively evaluated the clinical presentation and prognostic factors in 76 patients with Legionnaires' disease, reported by local physicians, in a large outbreak resulting from contamination of the water in a public bathhouse in Miyazaki, Japan. Fever, gastrointestinal tract symptoms, and abnormal neurological findings were seen in 95%, 35%, and 21% of the 76 patients, respectively. Respiratory tract symptoms were seen in only 42% of the patients, although all of these patients revealed pneumonia on chest X-ray. Only 20 (31%) of the 64 patients who had microbiological tests were reported to have positive results for one of the three microbiological tests (sputum culture, serology, and urinary antigen) which are specific for Legionella infection. Based on univariate analysis, the existence of neurological symptoms, elevated levels of C-reactive protein and transaminases, hyponatremia, a positive urinary antigen test, and serological evidence of Legionella infection were independent risk factors for poor clinical courses in patients with Legionnaires' disease. Patients treated with antimicrobial agents, such as macrolides, tetracyclines, and/or fluoroquinolones, within 3 days of onset of illness exhibited significantly better outcomes, when assessed by a multivariate logistic-regression model, after adjusting for the severity of pneumonia. Taking a careful history and documenting potential Legionella exposure, as well as microbiological testing, is important for an accurate diagnosis of Legionnaires' disease. Antimicrobials effective against Legionella bacteria should be administered without delay in subjects with suspected Legionnaires' disease.
Rift Valley fever (RVF) is a serious viral disease of animals and humans in Africa and the Middle East that is transmitted by mosquitoes. First isolated in Kenya during an outbreak in 1930, subsequent outbreaks have had a significant impact on animal and human health, as well as national economies. ...
Rift Valley fever (RVF) is a serious viral disease of animals and humans in Africa and the Middle East that is transmitted by mosquitoes. First isolated in Kenya during an outbreak in 1930 subsequent outbreaks have had a significant impact on animal and human health and national economies, and it is...
Schmidt, DJ; Pickett, BE; Camacho, D; Comach, G; Xhaja, K; Lennon, NJ; Rizzolo, K; de Bosch, N; Becerra, A; Nogueira, ML; Mondini, A; da Silva, EV; Vasconcelos, PF; Muñoz-Jordán, JL; Santiago, GA; Ocazionez, R; Gehrke, L; Lefkowitz, EJ; Birren, BW; Henn, MR; Bosch, I
Dengue virus currently causes 50-100 million infections annually. Comprehensive knowledge about the evolution of Dengue in response to selection pressure is currently unavailable, but would greatly enhance vaccine design efforts. In the current study, we sequenced 187 new dengue virus serotype 3(DENV-3) genotype III whole genomes isolated from Asia and the Americas. We analyzed them together with previously-sequenced isolates to gain a more detailed understanding of the evolutionary adaptations existing in this prevalent American serotype. In order to analyze the phylogenetic dynamics of DENV-3 during outbreak periods; we incorporated datasets of 48 and 11 sequences spanning two major outbreaks in Venezuela during 2001 and 2007-2008 respectively. Our phylogenetic analysis of newly sequenced viruses shows that subsets of genomes cluster primarily by geographic location, and secondarily by time of virus isolation. DENV-3 genotype III sequences from Asia are significantly divergent from those from the Americas due to their geographical separation and subsequent speciation. We measured amino acid variation for the E protein by calculating the Shannon entropy at each position between Asian and American genomes. We found a cluster of 7 amino acid substitutions having high variability within E protein domain III, which has previously been implicated in serotype-specific neutralization escape mutants. No novel mutations were found in the E protein of sequences isolated during either Venezuelan outbreak. Shannon entropy analysis of the NS5 polymerase mature protein revealed that a G374E mutation, in a region that contributes to interferon resistance in other flaviviruses by interfering with JAK-STAT signaling was present in both the Asian and American sequences from the 2007-2008 Venezuelan outbreak, but was absent in the sequences from the 2001 Venezuelan outbreak. In addition to E, several NS5 amino acid changes were unique to the 2007-2008 epidemic in Venezuela and may
Erfe, J Mark
The deadliest Ebola outbreak the world has ever seen is currently ravaging West Africa, despite the concerted efforts of the World Health Organization and many national governments. The current picture is troubling, but not altogether unexpected. Ebola was initially identified in 1976, and since that time, few drugs have been developed to combat it. The same is true for myriad other dangerous infectious diseases to which the world is currently susceptible. One proposal that might prevent outbreaks of this scale and magnitude from recurring would be to have the World Health Organization (WHO) and its technical partners assess which of its member states are at high risk for a disease, either directly or indirectly, and facilitate the creation of international governmental risk pools of those member states. Risk pools would offer open-indexed grant contracts to fund vaccine and drug development for a particular disease, and pharmaceutical companies could browse the index to apply for these grants. If the risk-pool states and a particular company sign a contract, a mutually agreed upon amount of the vaccine or drug would be produced at a below-market purchase price for those states. In return, the company would keep any patents or intellectual property rights for the developed vaccines or drugs. Risk-pool countries that did not use their vaccine or drug could resell that supply on secondary markets to other countries outside of the risk pool. This arrangement will increase the supply of tested drug and vaccine candidates available for combatting unexpected outbreaks of any previously discovered major infectious disease in the future.
Erfe, J. Mark
The deadliest Ebola outbreak the world has ever seen is currently ravaging West Africa, despite the concerted efforts of the World Health Organization and many national governments. The current picture is troubling, but not altogether unexpected. Ebola was initially identified in 1976, and since that time, few drugs have been developed to combat it. The same is true for myriad other dangerous infectious diseases to which the world is currently susceptible. One proposal that might prevent outbreaks of this scale and magnitude from recurring would be to have the World Health Organization (WHO) and its technical partners assess which of its member states are at high risk for a disease, either directly or indirectly, and facilitate the creation of international governmental risk pools of those member states. Risk pools would offer open-indexed grant contracts to fund vaccine and drug development for a particular disease, and pharmaceutical companies could browse the index to apply for these grants. If the risk-pool states and a particular company sign a contract, a mutually agreed upon amount of the vaccine or drug would be produced at a below-market purchase price for those states. In return, the company would keep any patents or intellectual property rights for the developed vaccines or drugs. Risk-pool countries that did not use their vaccine or drug could resell that supply on secondary markets to other countries outside of the risk pool. This arrangement will increase the supply of tested drug and vaccine candidates available for combatting unexpected outbreaks of any previously discovered major infectious disease in the future. PMID:25506281
Wood, J. L. N.; Newton, J. R.; Chanter, N.; Mumford, J. A.
Respiratory disease is important in horses, particularly in young Thoroughbred racehorses, and inflammation that is detected in the trachea and bronchi (termed inflammatory airway disease [IAD]) is more significant in this population in terms of impact and frequency than other presentations of respiratory disease. IAD, which is characterized by neutrophilic inflammation, mild clinical signs, and accumulation of mucus in the trachea, may be multifactorial, possibly involving infections and environmental and immunological factors, and its etiology remains unclear. This 3-year longitudinal study of young Thoroughbred racehorses was undertaken to characterize the associations of IAD and nasal discharge with viral and bacterial infections. IAD was statistically associated with tracheal infection with Streptococcus pneumoniae (capsule type 3), Streptococcus zooepidemicus, Actinobacillus spp., and Mycoplasma equirhinis and equine herpesvirus 1 and 4 infections, after adjustment for variation between training yards, seasons, and age groups. The association with S. pneumoniae and S. zooepidemicus was independent of prior viral infection and, critically, was dependent on the numbers of organisms isolated. S. pneumoniae was significant only in horses that were 2 years old or younger. The prevalence and incidence of IAD, S. zooepidemicus, and S. pneumoniae decreased in parallel with age, consistent with increased disease resistance, perhaps by the acquisition of immunity. The study provided evidence for S. zooepidemicus and S. pneumoniae playing an important etiological role in the pathogenesis of IAD in young horses. PMID:15634959
Wu, Kangyun; Byers, Derek E; Jin, Xiaohua; Agapov, Eugene; Alexander-Brett, Jennifer; Patel, Anand C; Cella, Marina; Gilfilan, Susan; Colonna, Marco; Kober, Daniel L; Brett, Tom J; Holtzman, Michael J
Viral infections and type 2 immune responses are thought to be critical for the development of chronic respiratory disease, but the link between these events needs to be better defined. Here, we study a mouse model in which infection with a mouse parainfluenza virus known as Sendai virus (SeV) leads to long-term activation of innate immune cells that drive IL-13-dependent lung disease. We find that chronic postviral disease (signified by formation of excess airway mucus and accumulation of M2-differentiating lung macrophages) requires macrophage expression of triggering receptor expressed on myeloid cells-2 (TREM-2). Analysis of mechanism shows that viral replication increases lung macrophage levels of intracellular and cell surface TREM-2, and this action prevents macrophage apoptosis that would otherwise occur during the acute illness (5-12 d after inoculation). However, the largest increases in TREM-2 levels are found as the soluble form (sTREM-2) long after clearance of infection (49 d after inoculation). At this time, IL-13 and the adapter protein DAP12 promote TREM-2 cleavage to sTREM-2 that is unexpectedly active in preventing macrophage apoptosis. The results thereby define an unprecedented mechanism for a feed-forward expansion of lung macrophages (with IL-13 production and consequent M2 differentiation) that further explains how acute infection leads to chronic inflammatory disease.
Subramaniam, Saravanan; Mohapatra, Jajati K; Das, Biswajit; Sanyal, Aniket; Pattnaik, Bramhadev
In recent times, majority of the foot-and-mouth disease (FMD) outbreaks in India are caused by serotype O Ind2001 lineage. The lineage has diverged into four sub-lineages (Ind2001a, b, c and d). We report here the genetic and antigenic analyses of nine Ind2001d isolates that caused outbreaks during April 2013-March 2014 in India. The length of the genomes of outbreak viruses varied between 8153 and 8181 nucleotides without any insertion or deletion in the coding region. Of the nine isolates analyzed antigenically against the currently used Indian vaccine strain INDR2/1975, eight showed good cross serological match (>0.3) indicating optimal antigenic coverage by the vaccine strain. An unprecedented deletion of 22 nucleotides between position 57 and 78 was observed in the 3' untranslated region of one of the isolates without compromising the virus viability, which imply that partial distortion in SL2 of 3'UTR may not have influence on virus viability at least under in-vitro conditions. Recently the Ind2001 lineage has been reported from several countries including Libya and spread of this lineage across a wide geographical area needs to be monitored carefully to avoid any future pandemic.
Schilling, Stefan; Emmerich, Petra; Klempa, Boris; Auste, Brita; Schnaith, Ebbo; Schmitz, Herbert; Krüger, Detlev H.; Günther, Stephan; Meisel, Helga
In Europe, hemorrhagic fever with renal syndrome results mainly from infection with Puumala virus (PUUV) or Dobrava virus. For 31 patients from a hantavirus disease outbreak in Lower Bavaria, a district in southeast Germany, serodiagnosis was undertaken by enzyme-linked immunosorbent assay, immunofluorescence assay, and immunoblot analysis. In a few of these cases, however, PUUV-specific typing of antibodies by these standard assays failed and a virus neutralization assay under biosafety level 3 conditions was required to verify the infection by this virus type. PUUV RNA was amplified by reverse transcription-PCR from acute-phase sera of three patients and was found to be very closely related to virus sequences obtained from bank voles (Clethrionomys glareolus) trapped in the same area. These findings link the outbreak with a novel PUUV lineage, “Bavaria,” circulating in the local rodent population. The Bavaria lineage associated with the outbreak is only distantly related to other PUUV lineages from Germany. PMID:17626170
Monma, Chie; Hatakeyama, Kaoru; Obata, Hiromi; Yokoyama, Keiko; Konishi, Noriko; Itoh, Takeshi; Kai, Akemi
The epidemiological and bacteriological investigations on four foodborne outbreaks caused by a new type of enterotoxin-producing Clostridium perfringens are described. C. perfringens isolated from patients of these outbreaks did not produce any known enterotoxin and did not carry the C. perfringens enterotoxin gene. However, the culture filtrates of these isolates induced the accumulation of fluid in rabbit ileal loop tests. The molecular weight of the new enterotoxin may be between 50,000 and 100,000, although the known C. perfringens enterotoxin is ca. 35,000. This new enterotoxin was heat labile, and its biological activities were inactivated by heating for 5 min at 60°C. The new enterotoxin was sensitive to pH values higher than 11.0 and protease treatment but was resistant to trypsin treatment. These results suggest that the new enterotoxin may be a protein. Although C. perfringens enterotoxin induced morphological changes in Vero cells, the changes induced by the new enterotoxin differed from those by the known C. perfringens enterotoxin. The new enterotoxin also induced morphological changes in L929 cells, whereas the known C. perfringens enterotoxin did not, because L929 cells lacked an appropriate enterotoxin receptor. Although C. perfringens enterotoxin is recognized as the only diarrheagenic toxin responsible for C. perfringens foodborne outbreaks, the results of the present study indicate that C. perfringens isolated from these four outbreaks produced a new type of enterotoxin.
Sabria, M; Alvarez, J; Dominguez, A; Pedrol, A; Sauca, G; Salleras, L; Lopez, A; Garcia-Nuñez, M A; Parron, I; Barrufet, M P
A community outbreak of Legionella pneumonia in the district of Cerdanyola, Mataró (Catalonia, Spain) was investigated in an epidemiological, environmental and molecular study. Each patient was interviewed to ascertain personal risk-factors and the clinical and epidemiological data. Isolates of Legionella from patients and water samples were subtyped by pulsed-field gel electrophoresis. Between 7 August and 25 August 2002, 113 cases of Legionella pneumonia fulfilling the outbreak case definition criteria were reported, with 84 (74%) cases being located within a 500-m radius of the suspected cooling tower source. In this area, the relative risk of being infected was 54.6 (95% CI 25.3-118.1) compared with individuals living far from the cooling tower. Considering the population residing in the Cerdanyola district (28,256 inhabitants) as a reference population, the attack rate for the outbreak was 399.9 cases/100,000 inhabitants, and the case fatality rate was 1.8%. A single DNA subtype was observed among the ten clinical isolates, and one of the subtypes from the cooling tower matched exactly with the clinical subtype. Nine days after closing the cooling tower, new cases of pneumonia caused by Legionella ceased to appear. The epidemiological features of the outbreak, and the microbiological and molecular investigations, implicated the cooling tower as the source of infection.
Srikiatkhachorn, Anon; Wichit, Sineewanlaya; Gibbons, Robert V.; Green, Sharone; Libraty, Daniel H.; Endy, Timothy P.; Ennis, Francis A.; Kalayanarooj, Siripen; Rothman, Alan L.
Background Infection with dengue viruses (DENV) causes a wide range of manifestations from asymptomatic infection to a febrile illness called dengue fever (DF), to dengue hemorrhagic fever (DHF). The in vivo targets of DENV and the relation between the viral burden in these cells and disease severity are not known. Method The levels of positive and negative strand viral RNA in peripheral blood monocytes, T/NK cells, and B cells and in plasma of DF and DHF cases were measured by quantitative RT-PCR. Results Positive strand viral RNA was detected in monocytes, T/NK cells and B cells with the highest amounts found in B cells. Viral RNA levels in CD14+ cells and plasma were significantly higher in DHF compared to DF, and in cases with a secondary infection compared to those undergoing a primary infection. The distribution of viral RNA among cell subpopulations was similar in DF and DHF cases. Small amounts of negative strand RNA were found in a few cases only. The severity of plasma leakage correlated with viral RNA levels in plasma and in CD14+ cells. Conclusions B cells were the principal cells containing DENV RNA in peripheral blood, but overall there was little active DENV RNA replication detectable in peripheral blood mononuclear cells (PBMC). Secondary infection and DHF were associated with higher viral burden in PBMC populations, especially CD14+ monocytes, suggesting that viral infection of these cells may be involved in disease pathogenesis. PMID:23284680
Gott, Chloe; Gates, Thomas; Dermody, Nadene; Brew, Bruce J.
Background The longitudinal rate and profile of cognitive decline in persons with stable, treated, and virally suppressed HIV infection is not established. To address this question, the current study quantifies the rate of cognitive decline in a cohort of virally suppressed HIV+ persons using clinically relevant definitions of decline, and determine cognitive trajectories taking into account historical and baseline HAND status. Methods Ninety-six HIV+ (clinically stable and virally undetectable) and 44 demographically comparable HIV- participants underwent standard neuropsychological testing at baseline and 18-months follow-up. We described clinically relevant cognitive trajectories based on standard definitions of historical and baseline HAND status and cognitive decline. Historical, moderate to severe HAND was formally diagnosed at the start of the cART era in 15/96 participants based on clinical neurological and neuropsychological assessment. The same standard of care has been applied to all participants at St. Vincent’s Hospital Infectious Disease Department for the duration of their HIV infection (median of 20 years). Results Relative to HIV- controls (4.5%), 14% of HIV+ participants declined (p = .11), they also scored significantly lower on the global change score (p = .03), processing speed (p = .02), and mental flexibility/inhibition (p = .02) domains. Having HAND at baseline significantly predicted cognitive decline at follow up (p = .005). We determined seven clinically relevant cognitive trajectories taking into account whether participant has a history of HAND prior to study entry (yes/no); their results on the baseline assessment (baseline impairment: yes/no) and their results on the 18-month follow up (decline or stable) which in order of prevalence were: 1) No HAND history, no baseline impairment, 18-month follow-up stable (39%), 2) No HAND history, baseline impairment, 18-month follow-up stable (35%), 3) History of HAND; baseline impairment, 18
Edmunds, Kelly L; Hunter, Paul R; Few, Roger; Bell, Diana J
Highly pathogenic avian influenza virus (HPAI) strain H5N1 has had direct and indirect economic impacts arising from direct mortality and control programmes in over 50 countries reporting poultry outbreaks. HPAI H5N1 is now reported as the most widespread and expensive zoonotic disease recorded and continues to pose a global health threat. The aim of this research was to assess the potential of utilising Hazard Analysis of Critical Control Points (HACCP) assessments in providing a framework for a rapid response to emerging infectious disease outbreaks. This novel approach applies a scientific process, widely used in food production systems, to assess risks related to a specific emerging health threat within a known zoonotic disease hotspot. We conducted a HACCP assessment for HPAI viruses within Vietnam's domestic poultry trade and relate our findings to the existing literature. Our HACCP assessment identified poultry flock isolation, transportation, slaughter, preparation and consumption as critical control points for Vietnam's domestic poultry trade. Introduction of the preventative measures highlighted through this HACCP evaluation would reduce the risks posed by HPAI viruses and pressure on the national economy. We conclude that this HACCP assessment provides compelling evidence for the future potential that HACCP analyses could play in initiating a rapid response to emerging infectious diseases.
Prikhodko, Victor G; Sandoval-Jaime, Carlos; Abente, Eugenio J; Bok, Karin; Parra, Gabriel I; Rogozin, Igor B; Ostlund, Eileen N; Green, Kim Y; Sosnovtsev, Stanislav V
Feline calicivirus (FCV) is a common cause of mild to severe upper respiratory tract disease (URTD) in cats. FCV strain 21223 was isolated from a kitten with severe pneumonia in a disease outbreak with unusually high mortality (35 %) that occurred in a Missouri feline colony in 1995-1996. Phylogenetic analysis of the genome sequence of strain 21223 indicated the emergence of a new FCV strain. Analysis of the full-length genome sequence of a closely related (99.5 % nucleotide identity) strain, 3786, obtained from an asymptomatic animal in the same colony four months later, showed the presence of seven amino acid substitutions, with six of them located in the VP1 capsid sequence encoded by ORF2. Comparative analysis of the E-region sequences (426-521 aa ORF2) presumably involved in virus-host cell receptor interactions did not identify amino acid substitutions unique to the virulent strain. We determined the complete genome sequences of four virus isolates that were collected in regional catteries in the months following the outbreak that were associated with different manifestations of the disease (URTD, chronic stomatitis, and gingivitis). We show that genetically distinct FCV strains were cocirculating in the area, and no apparent correlation could be made between overall sequence and observed disease.
Fehér, Enikő; Doszpoly, Andor; Horváth, Balázs; Marton, Szilvia; Forró, Barbara; Farkas, Szilvia L; Bányai, Krisztián; Juhász, Tamás
Ranaviruses are emerging pathogens associated with high mortality diseases in fish, amphibians and reptiles. Here we describe the whole genome sequence of two ranavirus isolates from brown bullhead (Ameiurus nebulosus) specimens collected in 2012 at two different locations in Hungary during independent mass mortality events. The two Hungarian isolates were highly similar to each other at the genome sequence level (99.9% nucleotide identity) and to a European sheatfish (Silurus glanis) origin ranavirus (ESV, 99.7%-99.9% nucleotide identity). The coding potential of the genomes of both Hungarian isolates, with 136 putative proteins, were shared with that of the ESV. The core genes commonly used in phylogenetic analysis of ranaviruses were not useful to differentiate the two brown bullhead ESV strains. However genome-wide distribution of point mutations and structural variations observed mainly in the non-coding regions of the genome suggested that the ranavirus disease outbreaks in Hungary were caused by different virus strains. At this moment, due to limited whole genome sequence data of ESV it is unclear whether these genomic changes are useful in molecular epidemiological monitoring of ranavirus disease outbreaks. Therefore, complete genome sequencing of further isolates will be needed to identify adequate genetic markers, if any, and demonstrate their utility in disease control and prevention.
Herod, Morgan R.; Ferrer-Orta, Cristina; Loundras, Eleni-Anna; Ward, Joseph C.; Verdaguer, Nuria; Rowlands, David J.
ABSTRACT The Picornaviridae is a large family of positive-sense RNA viruses that contains numerous human and animal pathogens, including foot-and-mouth disease virus (FMDV). The picornavirus replication complex comprises a coordinated network of protein-protein and protein-RNA interactions involving multiple viral and host-cellular factors. Many of the proteins within the complex possess multiple roles in viral RNA replication, some of which can be provided in trans (i.e., via expression from a separate RNA molecule), while others are required in cis (i.e., expressed from the template RNA molecule). In vitro studies have suggested that multiple copies of the RNA-dependent RNA polymerase (RdRp) 3D are involved in the viral replication complex. However, it is not clear whether all these molecules are catalytically active or what other function(s) they provide. In this study, we aimed to distinguish between catalytically active 3D molecules and those that build a replication complex. We report a novel nonenzymatic cis-acting function of 3D that is essential for viral-genome replication. Using an FMDV replicon in complementation experiments, our data demonstrate that this cis-acting role of 3D is distinct from the catalytic activity, which is predominantly trans acting. Immunofluorescence studies suggest that both cis- and trans-acting 3D molecules localize to the same cellular compartment. However, our genetic and structural data suggest that 3D interacts in cis with RNA stem-loops that are essential for viral RNA replication. This study identifies a previously undescribed aspect of picornavirus replication complex structure-function and an important methodology for probing such interactions further. IMPORTANCE Foot-and-mouth disease virus (FMDV) is an important animal pathogen responsible for foot-and-mouth disease. The disease is endemic in many parts of the world with outbreaks within livestock resulting in major economic losses. Propagation of the viral genome
Mercante, Jeffrey W.; Morrison, Shatavia S.; Desai, Heta P.; Raphael, Brian H.; Winchell, Jonas M.
Legionella pneumophila was first recognized as a cause of severe and potentially fatal pneumonia during a large-scale outbreak of Legionnaires’ disease (LD) at a Pennsylvania veterans’ convention in Philadelphia, 1976. The ensuing investigation and recovery of four clinical isolates launched the fields of Legionella epidemiology and scientific research. Only one of the original isolates, “Philadelphia-1”, has been widely distributed or extensively studied. Here we describe the whole-genome sequencing (WGS), complete assembly, and comparative analysis of all Philadelphia LD strains recovered from that investigation, along with L. pneumophila isolates sharing the Philadelphia sequence type (ST36). Analyses revealed that the 1976 outbreak was due to multiple serogroup 1 strains within the same genetic lineage, differentiated by an actively mobilized, self-replicating episome that is shared with L. pneumophila str. Paris, and two large, horizontally-transferred genomic loci, among other polymorphisms. We also found a completely unassociated ST36 strain that displayed remarkable genetic similarity to the historical Philadelphia isolates. This similar strain implies the presence of a potential clonal population, and suggests important implications may exist for considering epidemiological context when interpreting phylogenetic relationships among outbreak-associated isolates. Additional extensive archival research identified the Philadelphia isolate associated with a non-Legionnaire case of “Broad Street pneumonia”, and provided new historical and genetic insights into the 1976 epidemic. This retrospective analysis has underscored the utility of fully-assembled WGS data for Legionella outbreak investigations, highlighting the increased resolution that comes from long-read sequencing and a sequence type-matched genomic data set. PMID:27684472
Johnson, Matthew G; Adams, Jaymes; McDonald-Hamm, Christie; Wendelboe, Aaron; Bradley, Kristy K
West Nile virus (WNV) activity has fluctuated in the south-central United States since its introduction. Seasonal outbreaks are common, with three in Oklahoma during 2003, 2007, and 2012. Morbidity and mortality rates vary during each outbreak. Long-term neurologic sequelae in association with West Nile virus disease (WNVD) are well-described, but limited information is available about delayed mortality among acute WNV infection survivors. A retrospective cohort analysis of all confirmed and probable WNVD cases reported to the Oklahoma State Department of Health (OSDH) during 2003, 2007, and 2012 was performed. OSDH surveillance data and mortality data from Oklahoma's vital statistics database were used to construct a descriptive epidemiologic analysis of the geography, temporality, severity, and associated mortality for each outbreak season. A Kaplan-Meier survival curve and standardized mortality ratios (SMRs) were calculated to measure survival of the 2003 and 2007 WNVD cohorts. Seventy-nine cases during 2003, 107 cases during 2007, and 180 cases during 2012 met inclusion criteria. Median ages of the 2003, 2007, and 2012 cohorts were 48, 58, and 59 years, respectively; race, sex, and symptom information were not substantially different. Each outbreak season had a different severity, temporality, and geography. Age- and sex-adjusted SMRs for the combined 2003 and 2007 cohorts censored at 5 years was 0.9 (95% confidence interval 0.51-1.75); no substantial difference was observed between the survival curves. Although similar patterns of long-term mortality were evident on the survival curves, SMRs did not demonstrate increased 5-year cumulative risk for death for patients surviving acute WNV infection.
Dr. Susan Fisher-Hoch, Virologist and Epidemiologist, will discuss her research and travels associated with viral hemorrhagic fevers. From the Ebola outbreak in Reston, Virginia to outbreaks of Crimean Congo Hemorrhagic Fever in South Africa, Senegal, and Saudi Arabia, Dr. Fisher-Hoch has studied and tracked the pathophysiology of these viral diseases. These studies have led her from the Center for Disease Control in the United States, to Lyon, France where she was instrumental in designing, constructing, and rendering operational a laboratory capable of containing some of the world's most dangerous diseases.
Fisher-Hoch, Susan [University of Texas School of Public Health
Dr. Susan Fisher-Hoch, Virologist and Epidemiologist, will discuss her research and travels associated with viral hemorrhagic fevers. From the Ebola outbreak in Reston, Virginia to outbreaks of Crimean Congo Hemorrhagic Fever in South Africa, Senegal, and Saudi Arabia, Dr. Fisher-Hoch has studied and tracked the pathophysiology of these viral diseases. These studies have led her from the Center for Disease Control in the United States, to Lyon, France where she was instrumental in designing, constructing, and rendering operational a laboratory capable of containing some of the world's most dangerous diseases.
Rademacher, Chris; Linhares, Daniel; Harmon, Karen; Rotolo, Marisa; Sun, Yaxuan; Baum, David H.; Zimmerman, Jeffrey; Piñeyro, Pablo
We performed a longitudinal field study in a swine breeding herd that presented with an outbreak of vesicular disease (VD) that was associated with an increase in neonatal mortality. Initially, a USDA Foreign Animal Disease (FAD) investigation confirmed the presence of Senecavirus A (SVA) and ruled out the presence of exotic agents that produce vesicular lesions, e.g., foot-and-mouth disease virus and others. Subsequently, serum samples, tonsil swabs, and feces were collected from sows (n = 22) and their piglets (n = 33) beginning 1 week after the onset of the clinical outbreak and weekly for 6 weeks. The presence of SVA RNA was evaluated in all specimens collected by reverse transcriptase quantitative PCR (RT-qPCR) targeting a conserved region of the 5′ untranslated region (5′-UTR). The serological response (IgG) to SVA was evaluated by the weekly testing of sow and piglet serum samples on a SVA VP1 recombinant protein (rVP1) indirect enzyme-linked immunosorbent assay (ELISA). The rVP1 ELISA detected seroconversion against SVA in clinically affected and non-clinically affected sows at early stages of the outbreak as well as maternal SVA antibodies in offspring. Overall, the absence of vesicles (gross lesions) in SVA-infected animals and the variability of RT-qPCR results among specimen type demonstrated that a diagnostic algorithm based on the combination of clinical observations, RT-qPCR in multiple diagnostic specimens, and serology are essential to ensure an accurate diagnosis of SVA. PMID:27225408
Kouadio, Koffi Isidore; Clement, Peter; Bolongei, Josephus; Tamba, Alpha; Gasasira, Alex Ntale; Warsame, Abdihamid; Okeibunor, Joseph Chukwudi; Ota, Martin Okechukwu; Tamba, Boima; Gumede, Nicksy; Shaba, Keith; Poy, Alain; Salla, Mbaye; Mihigo, Richard; Nshimirimana, Deo
Ebola Virus Disease (EVD) outbreak was confirmed in Liberia on March 31st 2014. A response comprising of diverse expertise was mobilized and deployed to the country to contain transmission of Ebola and give relief to a people already impoverished from protracted civil war. This paper describes the epidemiological and surveillance response to the EVD outbreak in Lofa County in Liberia from March to September 2014. Five of the 6 districts of Lofa were affected. The most affected districts were Voinjama/Guardu Gbondi and Foya. By 26th September, 2014, a total of 619 cases, including 19.4% probable cases, 20.3% suspected cases and 44.2% confirmed cases were recorded by the Ebola Emergency Response Team (EERT) of Lofa County. Adults (20-50 years) were the most affected. Overall fatality rate was 53.3%. Twenty two (22) cases were reported among the Health Care Workers with a fatality rate of 81.8%. Seventy eight percent (78%) of the contacts successfully completed 21 days follow-up while 134 (6.15%) that developed signs and symptoms of EVD were referred to the ETU in Foya. The contributions of the weak health systems as well as socio-cultural factors in fueling the epidemic are highlighted. Importantly, the lessons learnt including the positive impact of multi-sectorial and multidisciplinary and coordinated response led by the government and community. Again, given that the spread of infectious disease can be considered a security threat every effort has to put in place to strengthen the health systems in developing countries including the International Health Regulation (IHR)'s core capacities. Key words: Ebola virus disease, outbreak, epidemiology and surveillance, socio-cultural factors, health system, West Africa.
Marques, Juan; Mendoza, Iván; Noya, Belkisyolé; Acquatella, Harry; Palacios, Igor; Marques-Mejias, María
Background Chagas disease affects more than 15 million people worldwide. Although vector-borne transmission has decreased, oral transmission has become important. Recently, our group published the clinical and epidemiological characteristics of the largest outbreak of orally transmitted Chagas disease reported till date. Objective: To describe electrocardiographic changes occurring in the study population during the outbreak caused by ingestion of contaminated guava juice. Methods We evaluated 103 positive cases, of which 76 (74%) were aged ≤ 18 years (average age: 9.1 ± 3.1 years) and 27 (26%) were aged > 18 years (average age: 46 ± 11.8 years). All patients underwent clinical evaluations and ECG. If the patients had palpitations or evident alterations of rhythm at baseline, ambulatory ECG monitoring was performed. Results A total of 68 cases (66%; 53 children and 15 adults) had ECG abnormalities. Further, 69.7% (53/76) of those aged ≤ 18 years and 56% (15/27) of those aged >18 years showed some ECG alteration (p = ns). ST-T abnormalities were observed in 37.86% cases (39/103) and arrhythmias were evident in 28.16% cases (29/103). ST alterations occurred in 72% of those aged ≤18 years compared with 19% of th ose aged >18 years (p < 0.0001). Conclusion This study reports the largest number of cases in the same outbreak of acute Chagas disease caused by oral contamination, with recorded ECGs. ECG changes suggestive of acute myocarditis and arrhythmias were the most frequent abnormalities found. PMID:23887736
Fa, John E.; Sharples, Colin M.; Bell, Diana J.; DeAngelis, Donald L.
We developed an individual-based model of Rabbit Viral Hemorrhagic Disease (RVHD) for European wild rabbits (Oryctolagus cuniculus L.), representing up to 1000 rabbits in four hectares. Model output for productivity and recruitment matched published values. The disease was density-dependent and virulence affected outcome. Strains that caused death after several days produced greater overall mortality than strains in which rabbits either died or recovered very quickly. Disease effect also depended on time of year. We also elaborated a larger scale model representing 25 km2 and 100,000+ rabbits, split into a number of grid-squares. This was a more traditional model that did not represent individual rabbits, but employed a system of dynamic equations for each grid-square. Disease spread depended on probability of transmission between neighboring grid-squares. Potential recovery from a major population crash caused by the disease relied on disease virulence and frequency of recurrence. The model's dependence on probability of disease transmission between grid-squares suggests the way that the model represents the spatial distribution of the population affects simulation. Although data on RVHD in Europe are lacking, our models provide a basis for describing the disease in realistic detail and for assessing influence of various social and spatial factors on spread.
Quiroz, Evelia; Aguilar, Patricia V; Cisneros, Julio; Tesh, Robert B; Weaver, Scott C
Venezuelan equine encephalitis (VEE) is a reemerging, mosquito-borne viral disease of the neotropics that is severely debilitating and sometimes fatal to humans. Periodic epidemics mediated by equine amplification have been recognized since the 1920s, but interepidemic disease is rarely recognized. We report here clinical findings and genetic characterization of 42 cases of endemic VEE detected in Panama from 1961-2004. Recent clusters of cases occurred in Darien (eastern Panama) and Panama provinces (central Panama) near rainforest and swamp habitats. Patients ranged from 10 months to 48 years of age, and the more severe cases with neurological complications, including one fatal infection, were observed in children. The VEE virus strains isolated from these cases all belonged to an enzootic, subtype ID lineage known to circulate among sylvatic vectors and rodent reservoir hosts in Panama and Peru. These findings underscore endemic VEE as an important but usually neglected arboviral disease of Latin America.
Nath, Barnali; Barman, Nagendra N; Kumar, Sachin
Newcastle disease virus (NDV) isolates recovered from different outbreaks in chicken flocks in Assam during 2014-15 were genotypically and pathotypically characterized. Nucleotide sequence analysis of fusion (F) and hemagglutinin protein genes showed a close similarity with genotype XIII strains of NDV. Amino acid sequence of F protein showed a virulent cleavage site (112)R-R-Q-K-R-F(117). Furthermore, pathogenicity test in one-day-old chicks and embryonated chicken eggs showed a virulent pathotype of the isolated NDV strains. The study will help us to understand the biology of circulating strains of NDV in Northeastern part of India.
Bastos, Claudilson J. C.; Aras, Roque; Mota, Gildo; Reis, Francisco; Dias, Juarez Pereira; de Jesus, Robson Silva; Freire, Miralba Silva; de Araújo, Eline G.; Prazeres, Juliana; Grassi, Maria Fernanda Rios
Background Outbreaks of orally transmitted Trypanosoma cruzi continue to be reported in Brazil and are associated with a high mortality rate, mainly due to myocarditis. Methods This study is a detailed report on the disease progression of acute Chagas disease in 13 patients who were infected during two micro-outbreaks in two northeastern Brazilian towns. Clinical outcomes as well as EKG and ECHO results are described, both before and after benznidazole treatment. Results Fever and dyspnea were the most frequent symptoms observed. Other clinical findings included myalgia, periorbital edema, headache and systolic murmur. Two patients died of cardiac failure before receiving benznidazole treatment. EKG and ECHO findings frequently showed a disturbance in ventricular repolarization and pericardial effusion. Ventricular dysfunction (ejection fraction <55%) was present in 27.3% of patients. After treatment, EKG readings normalized in 91.7% of patients. Ventricular repolarization abnormalities persisted in 50% of the patients, while sinus bradycardia was observed in 18%. The systolic ejection fraction normalized in two out of three patients with initially depressed ventricular function, while pericardial effusion disappeared. Conclusions Myocarditis is frequently found and potentially severe in patients with acute Chagas disease. Benznidazole treatment may improve clinical symptoms, as well as EKG and ECHO findings. PMID:20559542
Haga, Y; Funakoshi, O; Kuroe, K; Kanazawa, K; Nakajima, H; Saito, H; Murata, Y; Munakata, A; Yoshida, Y
The aetiology of Crohn's disease remains unknown, although evidence for a viral cause has long been sought. Recent studies have shown inflammation of the submucosal microvascular endothelium and granulomata, and endothelial cell cytoplasmic inclusions, consistent with paramyxovirus, were identified by electron microscopy suggesting a persistent measles virus infection in Crohn's disease. Measles, mumps, and rubella viruses were tested for Crohn's disease by polymerase chain reaction (PCR). RNA was extracted from resected intestinal specimens from 15 patients with Crohn's disease, 14 with ulcerative colitis, and 14 controls without inflammatory bowel disease. This was used to perform nested PCR after reverse transcription (RT) of the RNA to cDNA with primer pairs directed against two regions in the genome of the measles virus and one region in the mumps and rubella viral genomes. Despite enhanced sensitivity of nested RT-PCR, measles, mumps, and rubella viral genomic sequences were not found in any intestinal specimen. Images Figure 1 Figure 2 PMID:8801199
Filter, Matthias; Falenski, Alexander; Appel, Bernd; Käsbohrer, Annemarie
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
Weiser, Armin A; Thöns, Christian; Filter, Matthias; Falenski, Alexander; Appel, Bernd; Käsbohrer, Annemarie
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.
Deng, Zhuo-Hui; Lv, Shan; Lin, Jin-Yan; Lin, Rong-Xing; Pei, Fu-Quan
Angiostrongyliasis has been frequently reported from the People's Republic of China during the last decade. An outbreak of angiostrongyliasis among migrant laborers in Guangning, Guangdong Province is described here. A questionnaire was developed to collect epidemiological and clinical information about 17 migrant laborers from the Bai ethnic group in Dali, Yunnan Province. Serum samples were collected and tested by enzyme-linked immunosorbent assay. Rats and mollusks from the same area where patients had collected Pomacea canaliculata were examined for presence of Angiostrongylus cantonensis. All 17 Bai migrant laborers consumed P. canaliculata and six had meningitis 3-19 days after consumption of P. canaliculata. Headache, myalgia and fatigue were the most common symptoms. Blood samples from 5 patients were positive for antibodies to A. cantonensis. The places where the migrant laborers collected P. canaliculata were identified as endemic areas for A. cantonensis. This outbreak highlights the vulnerability of migrants to angiostrongyliasis.
Aota, Noriko; Shiohara, Tetsuo
Viral infections are most likely triggering factors of autoimmune diseases, although a single vial infection is not sufficient to cause clinically evident autoimmune diseases. Any disease that profoundly alters the immune system may cause perturbed viral infections, thereby rendering otherwise refractory patients susceptible to autoimmune diseases. In this regard, drug-induced hypersensitivity syndrome (DIHS), a drug rash characterized by sequential reactivations of herpesviruses and the subsequent development of autoimmune diseases, offers a unique opportunity to investigate the mechanism of how autoimmunity is elicited after viral infections. Indeed, several autoimmune diseases have been reported to occur at intervals of several months to years after clinical resolution of DIHS. Two representative cases who developed autoimmune diseases three to four years after DIHS are shown. Our recent analyses of the kinetics of a developing disease have shown that fully functional FoxP3(+) regulatory T (Treg) cells are expanded at the acute stage thereby allowing viral reactivations but lose their suppressive function coincident with their contraction upon clinical resolution. The functional defect of Treg cells would be responsible for the subsequent development of autoimmune diseases. Patients with DIHS need close monitoring because of possible progression to autoimmune diseases even after the complete resolution.
Sobarzo, Ariel; Eskira, Yael; Herbert, Andrew S.; Kuehne, Ana I.; Stonier, Spencer W.; Ochayon, David E.; Fedida-Metula, Shlomit; Balinandi, Steven; Kislev, Yaara; Tali, Neta; Lewis, Eli C.; Lutwama, Julius Julian; Dye, John M.; Yavelsky, Victoria; Lobel, Leslie
Recovery from ebolavirus infection in humans is associated with the development of both cell-mediated and humoral immune responses. According to recent studies, individuals that did not survive infection with ebolaviruses appear to have lacked a robust adaptive immune response and the expression of several early innate response markers. However, a comprehensive protective immune profile has yet to be described. Here, we examine cellular memory immune responses among survivors of two separate Ebolavirus outbreaks (EVDs) due to Sudan virus (SUDV) infection in Uganda—Gulu 2000–2001 and Kibaale 2012. Freshly collected blood samples were stimulated with inactivated SUDV, as well as with recombinant SUDV or Ebola virus (EBOV) GP (GP1–649). In addition, ELISA and plaque reduction neutralization assays were performed to determine anti-SUDV IgG titers and neutralization capacity. Cytokine expression was measured in whole blood cultures in response to SUDV and SUDV GP stimulation in both survivor pools, demonstrating recall responses that indicate immune memory. Cytokine responses between groups were similar but had distinct differences. Neutralizing, SUDV-specific IgG activity against irradiated SUDV and SUDV recombinant proteins were detected in both survivor cohorts. Furthermore, humoral and cell-mediated crossreactivity to EBOV and EBOV recombinant GP1–649 was observed in both cohorts. In conclusion, immune responses in both groups of survivors demonstrate persistent recognition of relevant antigens, albeit larger cohorts are required in order to reach greater statistical significance. The differing cytokine responses between Gulu and Kibaale outbreak survivors suggests that each outbreak may not yield identical memory responses and promotes the merits of studying the immune responses among outbreaks of the same virus. Finally, our demonstration of cross-reactive immune recognition suggests that there is potential for developing cross-protective vaccines for
Weese, J. Scott; Stull, Jason
A cluster of canine parainfluenza virus infections was identified in a veterinary referral hospital. While hospital-associated outbreaks of canine parainfluenza virus infection have not been previously reported, veterinary hospitals possess some of the same risk factors that may be present in traditional high-risk sites such as kennels. Hospital-associated transmission of canine respiratory pathogens, therefore, must be considered. PMID:23814307
Tuppurainen, E S M; Venter, E H; Coetzer, J A W; Bell-Sakyi, L
Lumpy skin disease (LSD) is of substantial economic importance for the cattle industry in Africa and the Near and Middle East. Several insect species are thought to transmit the disease mechanically. Recent transmission studies have demonstrated the first evidence for a role of hard (ixodid) ticks as vectors of lumpy skin disease virus (LSDV). The aim of this study was to attempt in vitro growth of the virus in Rhipicephalus spp. tick cell lines and investigate in vivo the presence of the virus in ticks collected from cattle during LSD outbreaks in Egypt and South Africa. No evidence was obtained for replication of LSDV in tick cell lines although the virus was remarkably stable, remaining viable for 35 days at 28°C in tick cell cultures, in growth medium used for tick cells and in phosphate buffered saline. Viral DNA was detected in two-thirds of the 56 field ticks, making this the first report of the presence of potentially virulent LSDV in ticks collected from naturally infected animals.
Garske, Tini; Van Kerkhove, Maria D.; Yactayo, Sergio; Ronveaux, Olivier; Lewis, Rosamund F.; Staples, J. Erin; Perea, William; Ferguson, Neil M.
Background Yellow fever is a vector-borne disease affecting humans and non-human primates in tropical areas of Africa and South America. While eradication is not feasible due to the wildlife reservoir, large scale vaccination activities in Africa during the 1940s to 1960s reduced yellow fever incidence for several decades. However, after a period of low vaccination coverage, yellow fever has resurged in the continent. Since 2006 there has been substantial funding for large preventive mass vaccination campaigns in the most affected countries in Africa to curb the rising burden of disease and control future outbreaks. Contemporary estimates of the yellow fever disease burden are lacking, and the present study aimed to update the previous estimates on the basis of more recent yellow fever occurrence data and improved estimation methods. Methods and Findings Generalised linear regression models were fitted to a dataset of the locations of yellow fever outbreaks within the last 25 years to estimate the probability of outbreak reports across the endemic zone. Environmental variables and indicators for the surveillance quality in the affected countries were used as covariates. By comparing probabilities of outbreak reports estimated in the regression with the force of infection estimated for a limited set of locations for which serological surveys were available, the detection probability per case and the force of infection were estimated across the endemic zone. The yellow fever burden in Africa was estimated for the year 2013 as 130,000 (95% CI 51,000–380,000) cases with fever and jaundice or haemorrhage including 78,000 (95% CI 19,000–180,000) deaths, taking into account the current level of vaccination coverage. The impact of the recent mass vaccination campaigns was assessed by evaluating the difference between the estimates obtained for the current vaccination coverage and for a hypothetical scenario excluding these vaccination campaigns. Vaccination campaigns
Enhanced surveillance of shellfish mortality to improve early detection and investigation of outbreaks of exotic or emerging infectious diseases: An example of a mass mortality outbreak of mussels, France 2014.
Lupo, C; Prou, J
This paper explores the relevance and feasibility of enhanced surveillance of mussel-related mortality based on regular telephone interviews of a key informant in a farming community. Based on qualitative analyses of data collected through semi-structured interviews, this method of participatory disease surveillance enabled the retrieval of high quality data during an outbreak of mussel mortality which occurred in Pertuis Charentais, France, in 2014. The findings illustrated that such an enhanced surveillance approach compared with the institutional shellfish health surveillance system could improve the early detection of outbreaks of mussel mortality by one week. This approach enabled a detailed description of the outbreak, showing higher incidence proportion in the Northern water bodies. It also captured relevant data for hypothesis generation for further outbreak investigations, integrating a global view of the health and disturbance of the coastal marine ecosystem. However, to be effective and sustainable, this flexible approach requires a pre-existing knowledge of the structure of the information network of the farmers' community. Such a community-based enhanced surveillance could increase the reactivity of the entire system to enable the earliest possible and most appropriate interventions to protect shellfish populations against exotic or emerging infectious diseases. This would also help to improve the vigilance of mussel farmers and foster their commitment, which is an essential element for sustainable shellfish health surveillance.
Jori, F; Caron, A; Thompson, P N; Dwarka, R; Foggin, C; de Garine-Wichatitsky, M; Hofmeyr, M; Van Heerden, J; Heath, L
Foot-and-mouth disease (FMD) inflicts severe economic losses within infected countries and is arguably the most important trade-restricting livestock disease in the world. In southern Africa, infected African buffaloes (Syncerus caffer) are the major reservoir of the South African Territories (SAT) types of the virus. With the progressive expansion of transfrontier conservation areas (TFCAs), the risk of FMD outbreaks is expected to increase due to a higher probability of buffalo/livestock contacts. To investigate the dynamics of FMD within and around the Great Limpopo TFCA (GLTFCA), 5 herds of buffaloes were sampled in June 2010 to characterize circulating viruses in South Africa and Zimbabwe. Three SAT-2 and three SAT-3 viral strains were isolated in both countries, including one that was genetically linked with a recent SAT-2 outbreak in Mozambique in 2011. In addition, two groups of unvaccinated cattle (n = 192) were serologically monitored for 1 year at the wildlife/livestock interface of Gonarezhou National Park (GNP) in Zimbabwe between April 2009 and January 2010, using the liquid-phase blocking ELISA (LPBE) and a test for antibodies directed against non-structural proteins (NSP). Neither clinical signs nor vaccination of cattle were reported during the study, yet a high proportion of the monitored cattle showed antibody responses against SAT-3 and SAT-1. Antibodies against NSP were also detected in 10% of the monitored cattle. The results of this study suggest that cattle grazing in areas adjacent to the GLTFCA can be infected by buffalo or other infected livestock and that cattle trade movements can act as efficient disseminators of FMD viruses to areas several hundred kilometres from the virus source. Current methods of surveillance of FMD at the GLTFCA interface seem insufficient to control for FMD emergence and dissemination and require urgent reassessment and regional coordination.
Barbieri, Elena S; Rodríguez, Daniela V; Marin, Raúl E; Setti, Walter; Romero, Sandra; Barrandeguy, María; Parreño, Viviana
Llama population from Argentina is mainly concentrated in the Andean Puna, Jujuy. Llamas represent an important economic resource for the Andean communities. The aim of this study was to investigate the prevalence of antibodies against viral antigens associated to viral diseases of economic impact (neonatal diarrhea, reproductive and respiratory syndromes). A total of 349 serum samples from adult llamas were analyzed. The obtained antibody prevalence was 100 % for Rotavirus A and 70 % for Bovine parainfluenza virus 3. In contrast, no reactors were detected to Bovine herpesvirus 1, Bovine viral diarrhea virus 1, Human influenza A virus (H1N1) and Equine influenza virus (H3N8). These results confirm the wide circulation of rotavirus and parainfluenza virus in Argentinean llamas and suggest that susceptibility to infection with bovine herpesvirus, pestivirus and influenza A viruses is low. This serologic survey provides novel information regarding the epidemiology of viral diseases affecting llamas from the Argentinean Andean Puna.
Exposure to bovine viral diarrhea viruses (BVDV) may result in acute and persistent infections. Persistent infections are the consequence of in utero exposure during the first trimester of gestation. The resulting persistently infected (PI) animals are immunotolerant to the virus. Clinical presen...
Bogus, Joshua; Gankpala, Lincoln; Fischer, Kerstin; Krentel, Alison; Weil, Gary J.; Fischer, Peter U.; Kollie, Karsor; Bolay, Fatorma K.
The recent outbreak of Ebola virus disease (EVD) interrupted mass drug administration (MDA) programs to control and eliminate neglected tropical diseases in Liberia. MDA programs treat entire communities with medication regardless of infection status to interrupt transmission and eliminate lymphatic filariasis and onchocerciasis. Following reports of hostilities toward health workers and fear that they might be spreading EVD, it was important to determine whether attitudes toward MDA might have changed after the outbreak. We surveyed 140 community leaders from 32 villages in Lofa County, Liberia, that had previously participated in MDA and are located in an area that was an early epicenter of the EVD outbreak. Survey respondents reported a high degree of community trust in the MDA program, and 97% thought their communities were ready to resume MDA. However, respondents predicted that fewer people would comply with MDA after the EVD epidemic than before. The survey also uncovered fears in the community that EVD and MDA might be linked. Respondents suggested that MDA programs emphasize to people that the medications are identical to those previously distributed and that MDA programs have nothing to do with EVD. PMID:26666700
Hershberger, P.; Gregg, J.; Grady, C.; Collins, R.; Winton, J.
Losses from infectious diseases are an important component of natural mortality among marine fish species, but factors controlling the ecology of these diseases and their potential responses to anthropogenic changes are poorly understood. We used viral hemorrhagic septicemia virus (VHSV) and a laboratory stock of Pacific herring Clupea pallasii to investigate the kinetics of viral shedding and its effect on disease transmission and host mortality. Outbreaks of acute disease, accompanied by mortality and viral shedding, were initiated after waterborne exposure of herring to concentrations of VHSV as low as 10 1 plaque-forming units (pfu) ml-1. Shed virus in flow-through tanks was first detected 4 to 5 d post-exposure, peaked after 6 to 10 d, and was no longer detected after 16 d. Shedding rates, calculated from density, flow and waterborne virus titer reached 1.8 to 5.0 ?? ?10 8 pfu fish-1 d-1. Onset of viral shedding was dose-dependent and preceded initial mortality by 2 d. At 21 d, cumulative mortality in treatment groups ranged from 81 to 100% and was dependent not on challenge dose, but on the kinetics and level of viral shedding by infected fish in the tank. Possible consequences of the viral shedding and disease kinetics are discussed in the context of epizootic initiation and perpetuation among populations of wild Pacific herring. ?? Inter-Research 2010.
Hershberger, Paul K.; Gregg, Jacob L.; Winton, James R.; Grady, Courtney; Collins, Rachael
Losses from infectious diseases are an important component of natural mortality among marine fish species, but factors controlling the ecology of these diseases and their potential responses to anthropogenic changes are poorly understood. We used viral hemorrhagic septicemia virus (VHSV) and a laboratory stock of Pacific herring Clupea pallasii to investigate the kinetics of viral shedding and its effect on disease transmission and host mortality. Outbreaks of acute disease, accompanied by mortality and viral shedding, were initiated after waterborne exposure of herring to concentrations of VHSV as low as 101 plaque-formin