Sample records for prevent dengue outbreaks

  1. Mediational Effects of Self-Efficacy Dimensions in the Relationship between Knowledge of Dengue and Dengue Preventive Behaviour with Respect to Control of Dengue Outbreaks: A Structural Equation Model of a Cross-Sectional Survey

    PubMed Central

    Isa, Affendi; Loke, Yoon K.; Smith, Jane R.; Papageorgiou, Alexia; Hunter, Paul R.

    2013-01-01

    Background Dengue fever is endemic in Malaysia, with frequent major outbreaks in urban areas. The major control strategy relies on health promotional campaigns aimed at encouraging people to reduce mosquito breeding sites close to people's homes. However, such campaigns have not always been 100% effective. The concept of self-efficacy is an area of increasing research interest in understanding how health promotion can be most effective. This paper reports on a study of the impact of self-efficacy on dengue knowledge and dengue preventive behaviour. Methods and Findings We recruited 280 adults from 27 post-outbreak villages in the state of Terengganu, east coast of Malaysia. Measures of health promotion and educational intervention activities and types of communication during outbreak, level of dengue knowledge, level and strength of self-efficacy and dengue preventive behaviour were obtained via face-to-face interviews and questionnaires. A structural equation model was tested and fitted the data well (?2?=?71.659, df?=?40, p?=?0.002, RMSEA?=?0.053, CFI?=?0.973, TLI?=?0.963). Mass media, local contact and direct information-giving sessions significantly predicted level of knowledge of dengue. Level and strength of self-efficacy fully mediated the relationship between knowledge of dengue and dengue preventive behaviours. Strength of self-efficacy acted as partial mediator in the relationship between knowledge of dengue and dengue preventive behaviours. Conclusions To control and prevent dengue outbreaks by behavioural measures, health promotion and educational interventions during outbreaks should now focus on those approaches that are most likely to increase the level and strength of self-efficacy. PMID:24086777

  2. Impact of a dengue outbreak experience in the preventive perceptions of the community from a temperate region: Madeira island, portugal.

    PubMed

    Nazareth, Teresa; Sousa, Carla Alexandra; Porto, Graça; Gonçalves, Luzia; Seixas, Gonçalo; Antunes, Luís; Silva, Ana Clara; Teodósio, Rosa

    2015-03-01

    The ability to effectively modify behaviours is increasingly relevant to attain and maintain a good health status. Current behaviour-change models and theories present two main approaches for (healthier) decision-making: one analytical/logical, and one experiential/emotional/intuitive. Therefore, to achieve an integral and dynamic understanding of the public perceptions both approaches should be considered: community surveys should measure cognitive understanding of health-risk contexts, and also explore how past experiences affect this understanding. In 2011, community perceptions regarding domestic source reduction were assessed in Madeira Island?. After Madeira's first dengue outbreak (2012) a unique opportunity to compare perceptions before and after the outbreak-experience occurred. This was the aim of this study, which constituted the first report on the effect of an outbreak experience on community perceptions regarding a specific vector-borne disease. A cross-sectional survey was performed within female residents at the most aegypti-infested areas. Perceptions regarding domestic source reduction were assessed according to the Essential Perception (EP)-analysis tool. A matching process paired individuals from studies performed before and after the outbreak, ensuring homogeneity in six determinant variables. After the outbreak, there were more female residents who assimilated the concepts considered to be essential to understand the proposed behaviour. Nevertheless, no significant difference was observed in the number of female residents who achieved the defined 'minimal understanding''. Moreover, most of the population (95.5%) still believed at least in one of the identified myths. After the outbreak some myths disappeared and others appeared. The present study quantified and explored how the experience of an outbreak influenced the perception regarding a dengue-preventive behaviour. The outbreak experience surprisingly led to the appearance of new myths within the population, apart from the expected increase of relevant concepts' assimilation. Monitoring public perceptions is therefore crucial to make preventing dengue campaigns updated and worthy. PMID:25767886

  3. Lessons learned from previous dengue outbreaks

    PubMed Central

    Wiwanitkit, Viroj

    2014-01-01

    Dengue is an important tropical infection caused by an arbovirus dengue. As a mosquito borne infection, this disease is widely spread in several tropical endemic countries. Millions of world populations are at risk for this arboviral infection. Each year, thousands of dengue infections are reported and there are several death cases. Each year, the outbreaks of dengue emerge in several countries and this implies the global importance of this infection. Fighting with dengue outbreak is important in public health. In this specific chapter, the author discussed lessons learned from previous dengue outbreaks.

  4. Dengue Outbreak in Hadramout, Yemen, 2010: An Epidemiological Perspective

    PubMed Central

    Ghouth, Abdulla Salim Bin; Amarasinghe, Ananda; Letson, G. William

    2012-01-01

    We analyzed surveillance data of a dengue outbreak (2010) reported to the Hadramout Health Office (Yemen) and retrospectively analyzed dengue-related epidemiological and entomological events reported in Hadramout from 2005 to 2009. A total of 630 immunoglobulin M (IgM) -confirmed dengue cases of 982 febrile cases was reported during the period from February to June of 2010; 12 cases died, giving case fatality a rate of 1.9%. Among febrile cases, the highest proportion of dengue cases (37.3%) was reported in the 15- to 24-year-old age group. The overall attack rate was 0.89/1,000. The average number of cases reported by month over the preceding 5-year period compared with the 2010 data is consistent with endemicity of dengue in the region and supports epidemic designation for the dengue activity in 2010. Recognition of endemic dengue transmission and potential for substantial dengue epidemics highlight the need for consistent laboratory-based surveillance that can support prevention and control activities accordingly. PMID:22665621

  5. Modelling interventions during a dengue outbreak.

    PubMed

    Barmak, D H; Dorso, C O; Otero, M; Solari, H G

    2014-03-01

    We present a stochastic dynamical model for the transmission of dengue that considers the co-evolution of the spatial dynamics of the vectors (Aedes aegypti) and hosts (human population), allowing the simulation of control strategies adapted to the actual evolution of an epidemic outbreak. We observed that imposing restrictions on the movement of infected humans is not a highly effective strategy. In contrast, isolating infected individuals with high levels of compliance by the human population is efficient even when implemented with delays during an ongoing outbreak. We also studied insecticide-spraying strategies assuming different (hypothetical) efficiencies. We observed that highly efficient fumigation strategies seem to be effective during an outbreak. Nevertheless, taking into account the controversial results on the use of spraying as a single control strategy, we suggest that carrying out combined strategies of fumigation and isolation during an epidemic outbreak should account for a suitable strategy for the attenuation of epidemic outbreaks. PMID:23800514

  6. Cost of dengue outbreaks: literature review and country case studies

    PubMed Central

    2013-01-01

    Background Dengue disease surveillance and vector surveillance are presumed to detect dengue outbreaks at an early stage and to save – through early response activities – resources, and reduce the social and economic impact of outbreaks on individuals, health systems and economies. The aim of this study is to unveil evidence on the cost of dengue outbreaks. Methods Economic evidence on dengue outbreaks was gathered by conducting a literature review and collecting information on the costs of recent dengue outbreaks in 4 countries: Peru, Dominican Republic, Vietnam, and Indonesia. The literature review distinguished between costs of dengue illness including cost of dengue outbreaks, cost of interventions and cost-effectiveness of interventions. Results Seventeen publications on cost of dengue showed a large range of costs from 0.2 Million US$ in Venezuela to 135.2 Million US$ in Brazil. However, these figures were not standardized to make them comparable. Furthermore, dengue outbreak costs are calculated differently across the publications, and cost of dengue illness is used interchangeably with cost of dengue outbreaks. Only one paper from Australia analysed the resources saved through active dengue surveillance. Costs of vector control interventions have been reported in 4 studies, indicating that the costs of such interventions are lower than those of actual outbreaks. Nine papers focussed on the cost-effectiveness of dengue vaccines or dengue vector control; they do not provide any direct information on cost of dengue outbreaks, but their modelling methodologies could guide future research on cost-effectiveness of national surveillance systems. The country case studies – conducted in very different geographic and health system settings - unveiled rough estimates for 2011 outbreak costs of: 12 million US$ in Vietnam, 6.75 million US$ in Indonesia, 4.5 million US$ in Peru and 2.8 million US$ in Dominican Republic (all in 2012 US$). The proportions of the different cost components (vector control; surveillance; information, education and communication; direct medical and indirect costs), as percentage of total costs, differed across the respective countries. Resources used for dengue disease control and treatment were country specific. Conclusions The evidence so far collected further confirms the methodological challenges in this field: 1) to define technically dengue outbreaks (what do we measure?) and 2) to measure accurately the costs in prospective field studies (how do we measure?). Currently, consensus on the technical definition of an outbreak is sought through the International Research Consortium on Dengue Risk Assessment, Management and Surveillance (IDAMS). Best practice guidelines should be further developed, also to improve the quality and comparability of cost study findings. Modelling the costs of dengue outbreaks and validating these models through field studies should guide further research. PMID:24195519

  7. The History of Dengue Outbreaks in the Americas

    PubMed Central

    Brathwaite Dick, Olivia; San Martín, José L.; Montoya, Romeo H.; del Diego, Jorge; Zambrano, Betzana; Dayan, Gustavo H.

    2012-01-01

    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

  8. Factors Associated with Larval Control Practices in a Dengue Outbreak Prone Area

    PubMed Central

    Mohamad, Mariam; Selamat, Mohamad Ikhsan; Ismail, Zaliha

    2014-01-01

    In order to reduce the risk of dengue outbreak recurrence in a dengue outbreak prone area, the members of the community need to sustain certain behavior to prevent mosquito from breeding. Our study aims to identify the factors associated with larval control practices in this particular community. A cross-sectional study involves 322 respondents living in a dengue outbreak prone area who were interviewed using a pretested questionnaire. The level of knowledge about Aedes mosquitoes, dengue transmission, its symptoms, and personal preventive measures ranges from fair to good. The level of attitude towards preventive measures was high. However, reported level of personal larval control practices was low (33.2%). Our multiple logistic regression analysis showed that only those with a good level of attitude towards personal preventive measure and frequent attendance to health campaigns were significantly associated with the good larval control practices. We conclude that, in a dengue outbreak prone area, having a good attitude towards preventive measures and frequent participation in health campaigns are important factors to sustain practices on larval control. PMID:25309602

  9. Predicting outbreaks of dengue fever according to climate

    E-print Network

    N° 410 July 2012 Predicting outbreaks of dengue fever according to climate Scientific news Actualidad cientifica Actualité scientifique Mainly vectored by the mosquito Aedes aegypti, dengue fever, causing more or less severe symptoms such as fever, muscular pain, headaches, digestive disor- ders

  10. Dengue and Dengue Haemorrhagic Fever in Children During the 2000 Outbreak in Chittagong, Bangladesh

    Microsoft Academic Search

    Farid Uddin Ahmed; Chowdhury B Mahmood; Jhulan Das Sharma; Syed Mesbahul Hoque; Rebecca Zaman; M Shameem Hasan

    An outbreak of dengue\\/dengue haemorrhagic fever occurred during 2000 in Chittagong, Bangladesh. A total of 72 children admitted to the Paediatrics ward of the Chittagong Medical College Hospital were evaluated. Sixty-four (89.0%) children came from the Chittagong metropolitan area and the rest 8 (11.0%) from the rural area. The clinical diagnosis of dengue fever (DF) was made in 26 children

  11. Outbreak of dengue virus serotype-2 (DENV-2) of Cambodian origin in Manipur, India - Association with meteorological factors

    PubMed Central

    Sankari, T.; Hoti, S.L.; Singh, Th Bhubonchandra; Shanmugavel, J.

    2012-01-01

    Background & objectives: Dengue is a major health problem in many parts of India and its neighbouring countries. Dengue cases have not been reported from Manipur, a northeastern State of India till 2007. But, the sudden outbreak of fever with febrile illness during 2007 and 2008, suspected to be dengue/dengue haemorrhagic fever was investigated to detect the causative agent. Potential impact of climatic variables on dengue transmission has been documented and hence the association between climatic factors, entomological parameters and dengue cases was also analysed. Methods: Forty two and 16 blood samples were collected from patients suspected to have dengue infection in the year 2007 and 2008, respectively. Viral RNA was extracted from serum samples and subjected to multiplex one step RT-PCR assay. Dengue specific amplicons were sequenced and phylogenetic analysis was carried out. Multiyear trend analysis and ‘t’ test were performed for the comparison of different meteorological variables between the years 2000-2004 and 2005-2008. Results: The aetiological agent was found to be DENV-2 and the phylogenetic analysis showed that the isolate was similar to that of Cambodian isolate. There was a significant difference in minimum temperature (P<0.05), Relative humidity - morning hours (P<0.001), relative humanity - afternoon hours (P<0.01) and cumulative precipitation (P< 0.05) between the years 2000-2004 and 2005-2008. Interpretation & conclusions: The sudden outbreak of dengue fever in Manipur State occurred was possibly due to the increased temperature, relative humidity and decrease in cumulative precipitation. These climatic factors would have contributed to the Aedes mosquito abundance and increased virus transmission. Proper diseases surveillance system integrated with meteorological warning system and management of vector breeding sites will prevent such outbreaks in future. PMID:23168706

  12. An outbreak of dengue fever in St. Croix (U. S. Virgin Islands), 2005.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the summer of 2005, an outbreak of dengue virus serotype-2 with cases of dengue hemorrhagic fever (DHF) occurred in St. Croix, US Virgin Islands. The medical records of all dengue laboratory-positive patients either seen in the Emergency Department of or admitted to the Governor Juan F. Luis Hosp...

  13. Spatiotemporal clustering, climate periodicity, and social-ecological risk factors for dengue during an outbreak in Machala, Ecuador, in 2010.

    PubMed

    Stewart-Ibarra, Anna M; Muñoz, Angel G; Ryan, Sadie J; Ayala, Efraín; Borbor-Cordova, Mercy J; Finkelstein, Julia L; Mejía, Raúl; Ordoñez, Tania; Recalde-Coronel, G; Rivero, Keytia

    2014-11-25

    BackgroundDengue fever, a mosquito-borne viral disease, is a rapidly emerging public health problem in Ecuador and throughout the tropics. However, we have a limited understanding of the disease transmission dynamics in these regions. Previous studies in southern coastal Ecuador have demonstrated the potential to develop a dengue early warning system (EWS) that incorporates climate and non-climate information. The objective of this study was to characterize the spatiotemporal dynamics and climatic and social-ecological risk factors associated with the largest dengue epidemic to date in Machala, Ecuador, to inform the development of a dengue EWS.MethodsThe following data from Machala were included in analyses: neighborhood-level georeferenced dengue cases, national census data, and entomological surveillance data from 2010; and time series of weekly dengue cases (aggregated to the city-level) and meteorological data from 2003 to 2012. We applied LISA and Moran¿s I to analyze the spatial distribution of the 2010 dengue cases, and developed multivariate logistic regression models through a multi-model selection process to identify census variables and entomological covariates associated with the presence of dengue at the neighborhood level. Using data aggregated at the city-level, we conducted a time-series (wavelet) analysis of weekly climate and dengue incidence (2003-2012) to identify significant time periods (e.g., annual, biannual) when climate co-varied with dengue, and to describe the climate conditions associated with the 2010 outbreak.ResultsWe found significant hotspots of dengue transmission near the center of Machala. The best-fit model to predict the presence of dengue included older age and female gender of the head of the household, greater access to piped water in the home, poor housing condition, and less distance to the central hospital. Wavelet analyses revealed that dengue transmission co-varied with rainfall and minimum temperature at annual and biannual cycles, and we found that anomalously high rainfall and temperatures were associated with the 2010 outbreak.ConclusionsOur findings highlight the importance of geospatial information in dengue surveillance and the potential to develop a climate-driven spatiotemporal prediction model to inform disease prevention and control interventions. This study provides an operational methodological framework that can be applied to understand the drivers of local dengue risk. PMID:25420543

  14. Risk factors associated with an outbreak of dengue fever/dengue haemorrhagic fever in Hanoi, Vietnam.

    PubMed

    Toan, D T T; Hoat, L N; Hu, W; Wright, P; Martens, P

    2014-10-13

    SUMMARY Dengue fever/dengue haemorrhagic fever (DF/DHF) appears to be emerging in Hanoi in recent years. A case-control study was performed to investigate risk factors for the development of DF/DHF in Hanoi. A total of 73 patients with DF/DHF and 73 control patients were included in the study. The risk factor analysis indicated that living in rented housing, living near uncovered sewers, and living in a house discharging sewage directly into to ponds were all significantly associated with DF/DHF. People living in rented houses were 2·2 times more at risk of DF/DHF than those living in their own homes [adjusted odds ratio (aOR) 2·2, 95% confidence interval (CI) 1·1-4·6]. People living in an unhygienic house, or in a house discharging sewage directly to the ponds were 3·4 times and 4·3 times, respectively, more likely to be associated with DF/DHF (aOR 3·4, 95% CI 1-11·7; aOR 4·3, 95% CI 1·1-16·9). These results contribute to the understanding of the dynamics of dengue transmission in Hanoi, which is needed to implement dengue prevention and control programmes effectively and efficiently. PMID:25308711

  15. Maiden outbreaks of dengue virus 1 genotype III in rural central India.

    PubMed

    Barde, P V; Kori, B K; Shukla, M K; Bharti, P K; Chand, G; Kumar, G; Ukey, M J; Ali, N A; Singh, N

    2015-01-01

    Dengue is regarded as the most important arboviral disease. Although sporadic cases have been reported, serotypes responsible for outbreaks have not been identified from central India over the last 20 years. We investigated two outbreaks of febrile illness, in August and November 2012, from Korea district (Chhattisgarh) and Narsinghpur district (Madhya Pradesh), respectively. Fever and entomological surveys were conducted in the affected regions. Molecular and serological tests were conducted on collected serum samples. Dengue-specific amplicons were sequenced and phylogenetic analyses were performed. In Korea and Narsinghpur districts 37·3% and 59% of cases were positive, respectively, for dengue infection, with adults being the worst affected. RT-PCR confirmed dengue virus serotype 1 genotype III as the aetiology. Ninety-six percent of infections were primary. This is the first time that dengue virus 1 outbreaks have been documented from central India. Introduction of the virus into the population and a conducive mosquitogenic environment favouring increased vector density caused the outbreak. Timely diagnosis and strengthening vector control measures are essential to avoid future outbreaks. PMID:24667083

  16. Dengue Fever Outbreak in Delhi, North India: A Clinico-Epidemiological Study

    PubMed Central

    Ahmed, Nishat Hussain; Broor, Shobha

    2015-01-01

    Background: Dengue viruses, single-stranded positive polarity ribonucleic acid (RNA) viruses of the family Flaviviridae, are the most common cause of arboviral disease in the world. We report a clinico-epidemiological study of the dengue fever outbreak of 2010 from a tertiary care hospital in Delhi, North India. Objectives: Objectives of the study were to know the incidence of laboratory-confirmed dengue cases among the clinically suspected patients; to study the clinical profile of dengue-positive cases; and to co-relate the above with the prevalent serotype and environmental conditions. Materials and Methods: Four thousand three hundred and seventy serum samples from clinically suspected cases of dengue infection were subjected to ?-capture enzyme-linked immunosorbent assay (ELISA) for detection of dengue-virus-specific IgM antibodies. Virus isolation was done in 55 samples on C6/36 cell mono-layers. Clinical and demographic details of the patients were obtained from requisition forms of the patients or from treating clinicians. Results: Out of the 4,370 serum samples, 1,700 were positive for dengue-virus-specific IgM antibodies (38.9%). Prevalent serotype was dengue virus type-1. Thrombocytopenia and myalgia was seen in 23.1% and 18.3% of the 1,700 dengue IgM-positive patients, respectively. Also, 10.3% of 1,700 were dengue hemorrhagic fever (DHF) patients; and the mortality in serologically confirmed dengue fever cases was 0.06%. Conclusions: A change in the predominant circulating serotype, unprecedented rains, enormous infrastructure development, and increased reporting due to improved diagnostic facilities were the factors responsible for the unexpected number of dengue fever cases confronted in 2010.

  17. Characteristics of a dengue outbreak in a remote pacific island chain--Republic of The Marshall Islands, 2011-2012.

    PubMed

    Sharp, Tyler M; Mackay, Andrew J; Santiago, Gilberto A; Hunsperger, Elizabeth; Nilles, Eric J; Perez-Padilla, Janice; Tikomaidraubuta, Kinisalote S; Colon, Candimar; Amador, Manuel; Chen, Tai-Ho; Lalita, Paul; Muñoz-Jordán, Jorge L; Barrera, Roberto; Langidrik, Justina; Tomashek, Kay M

    2014-01-01

    Dengue is a potentially fatal acute febrile illness caused by four mosquito-transmitted dengue viruses (DENV-1-4). Although dengue outbreaks regularly occur in many regions of the Pacific, little is known about dengue in the Republic of the Marshall Islands (RMI). To better understand dengue in RMI, we investigated an explosive outbreak that began in October 2011. Suspected cases were reported to the Ministry of Health, serum specimens were tested with a dengue rapid diagnostic test (RDT), and confirmatory testing was performed using RT-PCR and IgM ELISA. Laboratory-positive cases were defined by detection of DENV nonstructural protein 1 by RDT, DENV nucleic acid by RT-PCR, or anti-DENV IgM antibody by RDT or ELISA. Secondary infection was defined by detection of anti-DENV IgG antibody by ELISA in a laboratory-positive acute specimen. During the four months of the outbreak, 1,603 suspected dengue cases (3% of the RMI population) were reported. Of 867 (54%) laboratory-positive cases, 209 (24%) had dengue with warning signs, six (0.7%) had severe dengue, and none died. Dengue incidence was highest in residents of Majuro and individuals aged 10-29 years, and ?95% of dengue cases were experiencing secondary infection. Only DENV-4 was detected by RT-PCR, which phylogenetic analysis demonstrated was most closely related to a virus previously identified in Southeast Asia. Cases of vertical DENV transmission, and DENV/Salmonella Typhi and DENV/Mycobacterium leprae co-infection were identified. Entomological surveys implicated water storage containers and discarded tires as the most important development sites for Aedes aegypti and Ae. albopictus, respectively. Although this is the first documented dengue outbreak in RMI, the age groups of cases and high prevalence of secondary infection demonstrate prior DENV circulation. Dengue surveillance should continue to be strengthened in RMI and throughout the Pacific to identify and rapidly respond to future outbreaks. PMID:25268134

  18. Characteristics of a Dengue Outbreak in a Remote Pacific Island Chain – Republic of the Marshall Islands, 2011–2012

    PubMed Central

    Sharp, Tyler M.; Mackay, Andrew J.; Santiago, Gilberto A.; Hunsperger, Elizabeth; Nilles, Eric J.; Perez-Padilla, Janice; Tikomaidraubuta, Kinisalote S.; Colon, Candimar; Amador, Manuel; Chen, Tai-Ho; Lalita, Paul; Muñoz-Jordán, Jorge L.; Barrera, Roberto; Langidrik, Justina; Tomashek, Kay M.

    2014-01-01

    Dengue is a potentially fatal acute febrile illness caused by four mosquito-transmitted dengue viruses (DENV-1–4). Although dengue outbreaks regularly occur in many regions of the Pacific, little is known about dengue in the Republic of the Marshall Islands (RMI). To better understand dengue in RMI, we investigated an explosive outbreak that began in October 2011. Suspected cases were reported to the Ministry of Health, serum specimens were tested with a dengue rapid diagnostic test (RDT), and confirmatory testing was performed using RT-PCR and IgM ELISA. Laboratory-positive cases were defined by detection of DENV nonstructural protein 1 by RDT, DENV nucleic acid by RT-PCR, or anti-DENV IgM antibody by RDT or ELISA. Secondary infection was defined by detection of anti-DENV IgG antibody by ELISA in a laboratory-positive acute specimen. During the four months of the outbreak, 1,603 suspected dengue cases (3% of the RMI population) were reported. Of 867 (54%) laboratory-positive cases, 209 (24%) had dengue with warning signs, six (0.7%) had severe dengue, and none died. Dengue incidence was highest in residents of Majuro and individuals aged 10–29 years, and ?95% of dengue cases were experiencing secondary infection. Only DENV-4 was detected by RT-PCR, which phylogenetic analysis demonstrated was most closely related to a virus previously identified in Southeast Asia. Cases of vertical DENV transmission, and DENV/Salmonella Typhi and DENV/Mycobacterium leprae co-infection were identified. Entomological surveys implicated water storage containers and discarded tires as the most important development sites for Aedes aegypti and Ae. albopictus, respectively. Although this is the first documented dengue outbreak in RMI, the age groups of cases and high prevalence of secondary infection demonstrate prior DENV circulation. Dengue surveillance should continue to be strengthened in RMI and throughout the Pacific to identify and rapidly respond to future outbreaks. PMID:25268134

  19. Evaluation of Inapparent Dengue Infections During an Outbreak in Southern China

    PubMed Central

    Wang, Tao; Wang, Man; Shu, Bo; Chen, Xue-qin; Luo, Le; Wang, Jin-yu; Cen, Yong-zhuang; Anderson, Benjamin D.; Merrill, Mary M.; Merrill, Hunter R.; Lu, Jia-hai

    2015-01-01

    Few studies evaluating inapparent dengue virus (DENV) infections have been conducted in China. In 2013, a large outbreak of DENV occurred in the city of Zhongshan, located in Southern China, which provided an opportunity to assess the clinical spectrum of disease. During the outbreak, an investigation of 887 index case contacts was conducted to evaluate inapparent and symptomatic DENV infections. Post-outbreak, an additional 815 subjects from 4 towns with, and 350 subjects from 2 towns without reported autochthonous DENV transmission, as determined by clinical diagnosis, were evaluated for serological evidence of dengue IgG antibodies. Between July and November 2013, there were 19 imported and 809 autochthonous dengue cases reported in Zhongshan. Of 887 case contacts enrolled during the outbreak, 13 (1.5%) exhibited symptomatic DENV infection, while 28 (3.2%) were inapparent. The overall I:S ratio was 2.2:1 (95% CI: 1.1-4.2:1). Post-outbreak serological data showed that the proportion of DENV IgG antibody detection from the 4 towns with and the 2 towns without reported DENV transmission was 2.7% (95% CI: 1.6%-3.8%) and 0.6% (95% CI: 0-1.4%), respectively. The I:S ratio in the 3 towns where clinical dengue cases were predominately typed as DENV-1 was 11.0:1 (95% CI: 3.7-?:1). The ratio in the town where DENV-3 was predominately typed was 1.0:1 (95% CI: 0.5-?:1). In this cross-sectional study, data suggests a high I:S ratio during a documented outbreak in Zhongshan, Southern China. These results have important implications for dengue control, implying that inapparent cases might influence DENV transmission more than previously thought. PMID:25826297

  20. [Risk factors associated to the epidemic outbreak of dengue virus infection.

    PubMed

    García-Gutiérrez, María Del Rocío; Romero-Zepeda, Hilda; Salvador Romero-Márquez, Rubén

    2013-01-01

    Objective: to identify the risk factors associated to the epidemic of dengue virus infections occurred at Queretaro, Mexico. Methods: a case-control study was carried out on 49 cases and 49 controls. The data included: age, sex, residency, schooling, occupation, clinical data, sources infected with Aedes aegypti, travelling, source of waters, and protection to water recipients. The protection to door and windows was investigated. ?(2) test and odds ratio were estimated. Results: the age group of 20-39 years was the most affected and women predominated. The Satellite area contributed with 38 cases (77.1 %). The absence of mosquito nettings on windows had an OR = 1.8, and ignorance of preventive activities had an OR = 2.8, while the use of insecticides (OR = 0.30) and mosquito repellents (OR = 0.54) were protective factors. Conclusions: the epidemic outbreak in Queretaro confirmed that Aedes aegypti has adapted to greater heights. This fact should alert to the sanitary authorities to face the possibility of an epidemic outbreak with great affectation among population. PMID:24290012

  1. Dengue and chikungunya: long-distance spread and outbreaks in naïve areas.

    PubMed

    Rezza, Giovanni

    2014-12-01

    Mosquito-borne virus infections, such as dengue and chikungunya, are continuously expanding their geographical range. The dengue virus, which is known to be a common cause of febrile illness in tropical areas of the Old World, is now widespread in the Americas. In most affected areas, all the four dengue virus serotypes have circulated. Recently, small clusters of dengue have been identified also in Southern Europe during the hot season. The chikungunya virus, initially restricted to Central Africa, where is a common cause of sporadic cases or small outbreaks, and Asia, where it is used to cause large epidemics, has recently invaded new territories. After ravaging Indian Ocean Islands and the Indian subcontinent, CHIKV caused an outbreak in north-eastern Italy. Recently, chikungunya has reached the Caribbean, causing for the first time a large epidemic on the American continent. Although Aedes aegypti is the main vector of both viruses, Aedes albopictus, the Asian 'Tiger' mosquito, is now playing an increasingly important role, contributing to their spread in temperate climate areas. Hereby, we focus the attention on outbreaks of dengue and chikungunya occurring in previously disease-free areas and discuss factors associated with the long-distance spread of the vector-borne infections, such as mutations increasing viral fitness, climate change, urbanization, and globalization of humans and vectors. PMID:25491436

  2. The 2012 Madeira Dengue Outbreak: Epidemiological Determinants and Future Epidemic Potential

    PubMed Central

    Lourenço, José; Recker, Mario

    2014-01-01

    Dengue, a vector-borne viral disease of increasing global importance, is classically associated with tropical and sub-tropical regions around the world. Urbanisation, globalisation and climate trends, however, are facilitating the geographic spread of its mosquito vectors, thereby increasing the risk of the virus establishing itself in previously unaffected areas and causing large-scale epidemics. On 3 October 2012, two autochthonous dengue infections were reported within the Autonomous Region of Madeira, Portugal. During the following seven months, this first ‘European’ dengue outbreak caused more than 2000 local cases and 81 exported cases to mainland Europe. Here, using an ento-epidemiological mathematical framework, we estimate that the introduction of dengue to Madeira occurred around a month before the first official cases, during the period of maximum influx of airline travel, and that the naturally declining temperatures of autumn were the determining factor for the outbreak's demise in early December 2012. Using key estimates, together with local climate data, we further propose that there is little support for dengue endemicity on this island, but a high potential for future epidemic outbreaks when seeded between May and August—a period when detection of imported cases is crucial for Madeira's public health planning. PMID:25144749

  3. The 2012 Madeira dengue outbreak: epidemiological determinants and future epidemic potential.

    PubMed

    Lourenço, José; Recker, Mario

    2014-08-01

    Dengue, a vector-borne viral disease of increasing global importance, is classically associated with tropical and sub-tropical regions around the world. Urbanisation, globalisation and climate trends, however, are facilitating the geographic spread of its mosquito vectors, thereby increasing the risk of the virus establishing itself in previously unaffected areas and causing large-scale epidemics. On 3 October 2012, two autochthonous dengue infections were reported within the Autonomous Region of Madeira, Portugal. During the following seven months, this first 'European' dengue outbreak caused more than 2000 local cases and 81 exported cases to mainland Europe. Here, using an ento-epidemiological mathematical framework, we estimate that the introduction of dengue to Madeira occurred around a month before the first official cases, during the period of maximum influx of airline travel, and that the naturally declining temperatures of autumn were the determining factor for the outbreak's demise in early December 2012. Using key estimates, together with local climate data, we further propose that there is little support for dengue endemicity on this island, but a high potential for future epidemic outbreaks when seeded between May and August-a period when detection of imported cases is crucial for Madeira's public health planning. PMID:25144749

  4. Concurrent chikungunya and dengue virus infections during simultaneous outbreaks, Gabon, 2007.

    PubMed

    Leroy, Eric M; Nkoghe, Dieudoné; Ollomo, Benjamin; Nze-Nkogue, Chimène; Becquart, Pierre; Grard, Gilda; Pourrut, Xavier; Charrel, Rémi; Moureau, Grégory; Ndjoyi-Mbiguino, Angélique; De-Lamballerie, Xavier

    2009-04-01

    An outbreak of febrile illness occurred in Gabon in 2007, with 20,000 suspected cases. Chikungunya or dengue-2 virus infections were identified in 321 patients; 8 patients had documented co-infections. Aedes albopictus was identified as the principal vector for the transmission of both viruses. PMID:19331740

  5. Factors Affecting Dengue Prevention Practices: Nationwide Survey of the Malaysian Public

    PubMed Central

    Wong, Li Ping; Shakir, Sharina Mahavera Mohamad; Atefi, Narges; AbuBakar, Sazaly

    2015-01-01

    Background Efforts to stamp dengue in many dengue endemic countries has met little success. There is a need to re-examine and understand how the public at large view the dengue prevention efforts. This study aimed to examine the demographic factors, theoretical constructs of the Health Belief Model and knowledge about dengue and how these influence the practice of dengue prevention. Methods A national telephone survey was carried out with 2,512 individuals of the Malaysian public aged 18–60 years. Results The majority (73%) of the Malaysian public had a total dengue prevention score of 51–100 (of a possible score of 1–100). Multivariate analysis suggests significant correlates of higher dengue prevention practices with demographic background, perception of susceptibility to dengue, perceived density of mosquitoes in the neighbourhood and knowledge about dengue. Households of lower income of which the majority (40.7%) were from the rural areas, were associated with the highest odds [OR = 1.33; 95%CI = 1.09–1.67; p = 0.004] of dengue prevention. Dengue prevention practices were also less likely to be undertaken in neighbourhoods where the responders perceived there is no and/or low density of mosquitoes. Dengue prevention practices are also less likely to be practiced by skilled workers [OR = 0.78; 95%CI = 0.63–0.95; p = 0.029] compared to those unemployed. Higher perceived susceptibility to dengue was associated with higher dengue prevention practices and participants with higher dengue knowledge were found to have a higher level of involvement in dengue prevention practices. Conclusion Results from the study suggest that in formulating approaches to contain dengue, strategies should be developed to cultivate dengue prevention practices among urban population and target areas with low density of mosquitoes where public perceived a less likely chance of getting dengue. Dengue prevention campaigns should focus on messages highlighting the risk of contracting dengue and education to increase knowledge about dengue. PMID:25836366

  6. EXPLORATORY SPACE-TIME ANALYSIS OF REPORTED DENGUE CASES DURING AN OUTBREAK IN FLORIDA, PUERTO RICO, 1991-1992

    Microsoft Academic Search

    AMY C. MORRISON; ARTHUR GETIS; MARILYN SANTIAGO; JOSE G. RIGAU-PEREZ; PAUL REITER

    1998-01-01

    The spatial and temporal distributions of dengue cases reported during a 1991-1992 outbreak in Florida, Puerto Rico (population 5 8,689), were studied by using a Geographic Information System. A total of 377 dengue cases were identified from a laboratory-based dengue surveillance system and georeferenced by their residential addresses on digital zoning and U.S. Geological Survey topographic maps. Weekly case maps

  7. E. Coli: Preventing Outbreaks at Camp.

    ERIC Educational Resources Information Center

    McKinney, Mary D.

    1996-01-01

    One strain of E. coli is not usually found in foods, but has been related to consumption of undercooked ground beef. Symptoms are stomach cramps and diarrhea, and 2-7% of infections lead to hemolytic uremic syndrome, which is life threatening. Camps can prevent outbreaks by avoiding uncooked meat on overnight campouts and requiring appropriate…

  8. Public Health Responses to a Dengue Outbreak in a Fragile State: A Case Study of Nepal

    PubMed Central

    Griffiths, Karolina; Banjara, Megha Raj; O'Dempsey, T.; Munslow, B.; Kroeger, Axel

    2013-01-01

    Objectives. The number of countries reporting dengue cases is increasing worldwide. Nepal saw its first dengue outbreak in 2010, with 96% of cases reported in three districts. There are numerous policy challenges to providing an effective public health response system in a fragile state. This paper evaluates the dengue case notification, surveillance, laboratory facilities, intersectoral collaboration, and how government and community services responded to the outbreak. Methods. Qualitative data were collected through 20 in-depth interviews, with key stakeholders, and two focus-group discussions, with seven participants. Results. Limitations of case recognition included weak diagnostic facilities and private hospitals not incorporated into the case reporting system. Research on vectors was weak, with no virological surveillance. Limitations of outbreak response included poor coordination and an inadequate budget. There was good community mobilization and emergency response but no routine vector control. Conclusions. A weak state has limited response capabilities. Disease surveillance and response plans need to be country-specific and consider state response capacity and the level of endemicity. Two feasible solutions for Nepal are (1) go upwards to regional collaboration for disease and vector surveillance, laboratory assistance, and staff training; (2) go downwards to expand upon community mobilisation, ensuring that vector control is anticipatory to outbreaks. PMID:23690789

  9. Best Practices in Dengue Surveillance: A Report from the Asia-Pacific and Americas Dengue Prevention Boards

    PubMed Central

    Beatty, Mark E.; Stone, Amy; Fitzsimons, David W.; Hanna, Jeffrey N.; Lam, Sai Kit; Vong, Sirenda; Guzman, Maria G.; Mendez-Galvan, Jorge F.; Halstead, Scott B.; Letson, G. William; Kuritsky, Joel; Mahoney, Richard; Margolis, Harold S.

    2010-01-01

    Background Dengue fever is a virus infection that is spread by the Aedes aegypti mosquito and can cause severe disease especially in children. Dengue fever is a major problem in tropical and sub-tropical regions of the world. Methodology/Principal Findings We invited dengue experts from around the world to attend meetings to discuss dengue surveillance. We reviewed literature, heard detailed reports on surveillance programs, and shared expert opinions. Results Presentations by 22 countries were heard during the 2.5 day meetings. We describe the best methods of surveillance in general, the stakeholders in dengue surveillance, and the steps from mosquito bite to reporting of a dengue case to explore how best to carry out dengue surveillance. We also provide details and a comparison of the dengue surveillance programs by the presenting countries. Conclusions/Significance The experts provided recommendations for achieving the best possible data from dengue surveillance accepting the realities of the real world (e.g., limited funding and staff). Their recommendations included: (1) Every dengue endemic country should make reporting of dengue cases to the government mandatory; (2) electronic reporting systems should be developed and used; (3) at minimum dengue surveillance data should include incidence, hospitalization rates, deaths by age group; (4) additional studies should be completed to check the sensitivity of the system; (5) laboratories should share expertise and data; (6) tests that identify dengue virus should be used in patients with fever for four days or less and antibody tests should be used after day 4 to diagnose dengue; and (7) early detection and prediction of dengue outbreaks should be goals for national surveillance systems. PMID:21103381

  10. Vector dynamics and transmission of dengue virus: implications for dengue surveillance and prevention strategies: vector dynamics and dengue prevention.

    PubMed

    Scott, Thomas W; Morrison, Amy C

    2010-01-01

    Accounting for variation in mosquito vector populations will improve dengue surveillance and prevention. Because Aedes aegypti, the principle dengue virus (DENV) vector, transmit the virus with remarkable efficiency, entomological thresholds are especially low. Assessing risk of human infection based on immature mosquito indices has proven difficult. Greater emphasis should be placed on relative abundance of adult vectors in relation to human serotype-specific herd immunity, introduction of unique viruses, mosquito-human contact and weather. The most appropriate spatial scale for assessing entomological risk is the individual household. The scale for measuring DENV transmission risk has yet to be determined but is clearly larger than the household and likely to exceed several city blocks. Because households are expected to be a primary site for human DENV infection, intradomicile vector control strategies should be a priority, especially when the force of transmission is high. The most effective intervention strategy will combine vector control with vaccine delivery for rapid and sustained disease prevention. PMID:19802582

  11. Dengue Outbreak in a Hilly State of Arunachal Pradesh in Northeast India

    PubMed Central

    Khan, Siraj A.; Dutta, Prafulla; Topno, Rashmee; Soni, Monika; Mahanta, Jagadish

    2014-01-01

    Dengue has been reported from plains as well as hilly regions of India including some parts of Northeast India. In July-August 2012, outbreak of fever with unknown origin (FUO) indicative of Dengue was reported in Pasighat, East Siang district of Arunachal Pradesh (AP) state. Serum samples (n = 164) collected from patients from Health Training and Research Centre General Hospital, Pasighat, were tested for NS1 antigen and IgM antibodies. NS1-positive samples were analyzed by RT-PCR assay and entomological surveys were carried out. The majority of suspected cases reported NS1 antigen positivity. Females and young adults were mostly affected. The majority of the amplified NS1-positive samples showed Dengue serotype 3 infection. Aedes (Stegomyia) albopictus, known as semiurban breeding mosquitoes, was the only potential vector species identified from the affected areas of Pasighat which single handedly contributed to the outbreak. Thus, the present work identifies Dengue as an emerging arboviral infection in hilly state of AP along with a looming risk of its spread to neighbouring areas. PMID:24587732

  12. Intra- and interseasonal autoregressive prediction of dengue outbreaks using local weather and regional climate for a tropical environment in Colombia.

    PubMed

    Eastin, Matthew D; Delmelle, Eric; Casas, Irene; Wexler, Joshua; Self, Cameron

    2014-09-01

    Dengue fever transmission results from complex interactions between the virus, human hosts, and mosquito vectors-all of which are influenced by environmental factors. Predictive models of dengue incidence rate, based on local weather and regional climate parameters, could benefit disease mitigation efforts. Time series of epidemiological and meteorological data for the urban environment of Cali, Colombia are analyzed from January of 2000 to December of 2011. Significant dengue outbreaks generally occur during warm-dry periods with extreme daily temperatures confined between 18°C and 32°C--the optimal range for mosquito survival and viral transmission. Two environment-based, multivariate, autoregressive forecast models are developed that allow dengue outbreaks to be anticipated from 2 weeks to 6 months in advance. These models have the potential to enhance existing dengue early warning systems, ultimately supporting public health decisions on the timing and scale of vector control efforts. PMID:24957546

  13. Intra- and Interseasonal Autoregressive Prediction of Dengue Outbreaks Using Local Weather and Regional Climate for a Tropical Environment in Colombia

    PubMed Central

    Eastin, Matthew D.; Delmelle, Eric; Casas, Irene; Wexler, Joshua; Self, Cameron

    2014-01-01

    Dengue fever transmission results from complex interactions between the virus, human hosts, and mosquito vectors—all of which are influenced by environmental factors. Predictive models of dengue incidence rate, based on local weather and regional climate parameters, could benefit disease mitigation efforts. Time series of epidemiological and meteorological data for the urban environment of Cali, Colombia are analyzed from January of 2000 to December of 2011. Significant dengue outbreaks generally occur during warm-dry periods with extreme daily temperatures confined between 18°C and 32°C—the optimal range for mosquito survival and viral transmission. Two environment-based, multivariate, autoregressive forecast models are developed that allow dengue outbreaks to be anticipated from 2 weeks to 6 months in advance. These models have the potential to enhance existing dengue early warning systems, ultimately supporting public health decisions on the timing and scale of vector control efforts. PMID:24957546

  14. Advances in the understanding, management, and prevention of dengue.

    PubMed

    Hermann, Laura L; Gupta, Swati B; Manoff, Susan B; Kalayanarooj, Siripen; Gibbons, Robert V; Coller, Beth-Ann G

    2015-03-01

    Dengue causes more human morbidity globally than any other vector-borne viral disease. Recent research has led to improved epidemiological methods that predict disease burden and factors involved in transmission, a better understanding of immune responses in infection, and enhanced animal models. In addition, a number of control measures, including preventative vaccines, are in clinical trials. However, significant gaps remain, including the need for better surveillance in large parts of the world, methods to predict which individuals will develop severe disease, and immunologic correlates of protection against dengue illness. During the next decade, dengue will likely expand its geographic reach and become an increasing burden on health resources in affected areas. Licensed vaccines and antiviral agents are needed in order to effectively control dengue and limit disease. PMID:25453329

  15. Dengue and Severe Dengue

    MedlinePLUS

    ... new areas, but explosive outbreaks are occurring. The threat of a possible outbreak of dengue fever now ... C/100°F) and include: severe abdominal pain, persistent vomiting, rapid breathing, bleeding gums, fatigue, restlessness and ...

  16. Preventing extinction and outbreaks in chaotic populations

    E-print Network

    Frank M. Hilker; Frank H. Westerhoff

    2007-08-29

    Interactions in ecological communities are inherently nonlinear and can lead to complex population dynamics including irregular fluctuations induced by chaos. Chaotic population dynamics can exhibit violent oscillations with extremely small or large population abundances that might cause extinction and recurrent outbreaks, respectively. We present a simple method that can guide management efforts to prevent crashes, peaks, or any other undesirable state. At the same time, the irregularity of the dynamics can be preserved when chaos is desirable for the population. The control scheme is easy to implement because it relies on time series information only. The method is illustrated by two examples: control of crashes in the Ricker map and control of outbreaks in a stage-structured model of the flour beetle Tribolium. It turns out to be effective even with few available data and in the presence of noise, as is typical for ecological settings.

  17. Sharing experiences: towards an evidence based model of dengue surveillance and outbreak response in Latin America and Asia

    PubMed Central

    2013-01-01

    Background The increasing frequency and intensity of dengue outbreaks in endemic and non-endemic countries requires a rational, evidence based response. To this end, we aimed to collate the experiences of a number of affected countries, identify strengths and limitations in dengue surveillance, outbreak preparedness, detection and response and contribute towards the development of a model contingency plan adaptable to country needs. Methods The study was undertaken in five Latin American (Brazil, Colombia, Dominican Republic, Mexico, Peru) and five in Asian countries (Indonesia, Malaysia, Maldives, Sri Lanka, Vietnam). A mixed-methods approach was used which included document analysis, key informant interviews, focus-group discussions, secondary data analysis and consensus building by an international dengue expert meeting organised by the World Health Organization, Special Program for Research and Training in Tropical Diseases (WHO-TDR). Results Country information on dengue is based on compulsory notification and reporting (“passive surveillance”), with laboratory confirmation (in all participating Latin American countries and some Asian countries) or by using a clinical syndromic definition. Seven countries additionally had sentinel sites with active dengue reporting, some also had virological surveillance. Six had agreed a formal definition of a dengue outbreak separate to seasonal variation in case numbers. Countries collected data on a range of warning signs that may identify outbreaks early, but none had developed a systematic approach to identifying and responding to the early stages of an outbreak. Outbreak response plans varied in quality, particularly regarding the early response. The surge capacity of hospitals with recent dengue outbreaks varied; those that could mobilise additional staff, beds, laboratory support and resources coped best in comparison to those improvising a coping strategy during the outbreak. Hospital outbreak management plans were present in 9/22 participating hospitals in Latin-America and 8/20 participating hospitals in Asia. Conclusions Considerable variation between countries was observed with regard to surveillance, outbreak detection, and response. Through discussion at the expert meeting, suggestions were made for the development of a more standardised approach in the form of a model contingency plan, with agreed outbreak definitions and country-specific risk assessment schemes to initiate early response activities according to the outbreak phase. This would also allow greater cross-country sharing of ideas. PMID:23800243

  18. Dengue

    MedlinePLUS

    ... the continental United States, it is endemic in Puerto Rico and in many popular tourist destinations in Latin ... Climate Dengue Update CDC's Dengue Branch Dengue in Puerto Rico Print page Get email updates View page in ...

  19. Dengue

    MedlinePLUS

    ... in the United States. Symptoms include a high fever, headaches, joint and muscle pain, vomiting, and a ... In some cases, dengue turns into dengue hemorrhagic fever, which causes bleeding from your nose, gums, or ...

  20. The Basic Reproduction Number ?0 and Effectiveness of Reactive Interventions during Dengue Epidemics: The 2002 Dengue Outbreak in Easter Island, Chile

    PubMed Central

    Chowell, G.; Fuentes, R.; Olea, A.; Aguilera, X.; Nesse, H.; Hyman, J. M.

    2015-01-01

    We use a stochastic simulation model to explore the effect of reactive intervention strategies during the 2002 dengue outbreak in the small population of Easter Island, Chile. We quantified the effect of interventions on the transmission dynamics and epidemic size as a function of the simulated control intensity levels and the timing of initiation of control interventions. Because no dengue outbreaks had been reported prior to 2002 in Easter Island, the 2002 epidemic provided a unique opportunity to estimate the basic reproduction number ?0 during the initial epidemic phase, prior to the start of control interventions. We estimated ?0 at 27.2 (95%CI: 14.8, 49.3). We found that the final epidemic size is highly sensitive to the timing of start of interventions. However, even when the control interventions start several weeks after the epidemic onset, reactive intervention efforts can have a significant impact on the final epidemic size. Our results indicate that the rapid implementation of control interventions can have a significant effect in reducing the epidemic size of dengue epidemics. PMID:24245625

  1. Study on Entomological Surveillance and its Significance during a Dengue Outbreak in the District of Tirunelveli in Tamil Nadu, India

    PubMed Central

    Basker, Parasuraman; Kannan, Pichai; Porkaipandian, Rajagopal Thirugnanasambandam; Saravanan, Sivsankaran; Sridharan, Subramaniam; Kadhiresan, Mahaligam

    2013-01-01

    Objectives To study the significance of entomological surveillance, the house index (HI), container index (CI), and Breteau index (BI) were determined to estimate the degree of a major dengue outbreak in Tirunelveli, Tamil Nadu, India (Latitude: 8°42?N; Longitude: 77°42?E) in May 2012. Methods The HI, CI, and BI were determined in a primary health center (PHC) in the village of Maruthamputhur (Pappakudi taluk, Tirunelveli) by carrying out an antilarval (AL) work that involved door-to-door search for immature stages of Aedes spp. mosquitoes by trained field workers and volunteers. The work of field workers was evaluated by a junior and senior entomologist the following day. Results Before the AL work, the reported numbers of fever cases from Week 1 to 5 in Maruthamputhur were 211, 394, 244, 222, and 144 with two deaths. By contrast, after the AL work, these numbers were considerably reduced and there was no fever-related death (the HI was reduced from 48.2% to 1.6%, the CI from 28.6% to 0.4%, and the BI from 48.2 to 1.6). Conclusion Because no specific medicine and vaccines are available to treat dengue fever and dengue hemorrhagic fever, entomological surveillance and its significance can be used to halt the outbreak of dengue as shown in this study. PMID:24159547

  2. Vaccines for Dengue

    Cancer.gov

    Among the arthropod-borne flaviviruses, the four dengue virus serotypes, dengue type 1 virus (DENV-1), dengue type 2 virus (DENV-2), dengue type 3 virus (DENV-3), and dengue type 4 virus (DENV-4) are most important in terms of human morbidity and geographic distribution. Dengue viruses cause dengue outbreaks and major epidemics in most tropical and subtropical areas where Aedes albopictus and Aedes aegypti mosquitoes are abundant.

  3. ProactiveVector control strategies and improved monitoring and evaluation practices for dengue prevention.

    PubMed

    Eisen, Lars; Beaty, Barry J; Morrison, Amy C; Scott, Thomas W

    2009-11-01

    Despite tremendous efforts by public health organizations in dengue-endemic countries, it has proven difficult to achieve effective and sustainable control of the primary dengue virus vector Aedes aegypti (L.) and to effectively disrupt dengue outbreaks. This problem has multiple root causes, including uncontrolled urbanization, increased global spread of dengue viruses, and vector and dengue control programs not being provided adequate resources. In this forum article, we give an overview of the basic elements of a vector and dengue control program and describe a continuous improvement cyclical model to systematically and incrementally improve control program performance by regular efforts to identify ineffective methods and inferior technology, and then replacing them with better performing alternatives. The first step includes assessments of the overall resource allocation among vector/dengue control program activities, the efficacy of currently used vector control methods, and the appropriateness of technology used to support the program. We expect this will reveal that 1) some currently used vector control methods are not effective, 2) resource allocations often are skewed toward reactive vector control measures, and 3) proactive approaches commonly are underfunded and therefore poorly executed. Next steps are to conceptualize desired changes to vector control methods or technologies used and then to operationally determine in pilot studies whether these changes are likely to improve control program performance. This should be followed by a shift in resource allocation to replace ineffective methods and inferior technology with more effective and operationally tested alternatives. The cyclical and self-improving nature of the continuous improvement model will produce locally appropriate management strategies that continually are adapted to counter changes in vector population or dengue virus transmission dynamics. We discuss promising proactive vector control approaches and the continued need for the vector and dengue control community to incorporate emerging technologies and to partner with academia, business and the community-at-large to identify new solutions that reduce dengue. PMID:19960667

  4. Shellfish-associated enteric virus illness: virus localization, disease outbreaks and prevention

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  5. Dengue: a continuing global threat

    Microsoft Academic Search

    Maria G. Guzman; Scott B. Halstead; Harvey Artsob; Philippe Buchy; Jeremy Farrar; Duane J. Gubler; Elizabeth Hunsperger; Axel Kroeger; Harold S. Margolis; Eric Martínez; Michael B. Nathan; Jose Luis Pelegrino; Cameron Simmons; Sutee Yoksan; Rosanna W. Peeling

    Dengue fever and dengue haemorrhagic fever are important arthropod-borne viral diseases. Each year, there are ?50 million dengue infections and ?500,000 individuals are hospitalized with dengue haemorrhagic fever, mainly in Southeast Asia, the Pacific and the Americas. Illness is produced by any of the four dengue virus serotypes. A global strategy aimed at increasing the capacity for surveillance and outbreak

  6. Dengue Outbreaks in High-Income Area, Kaohsiung City, Taiwan, 2003–2009

    PubMed Central

    Schiøler, Karin L.; Jepsen, Martin R.; Ho, Chi-Kung; Li, Shu-Hua; Konradsen, Flemming

    2012-01-01

    Kaohsiung City, a modern metropolis of 1.5 million persons, has been the focus of dengue virus activity in Taiwan for several decades. The aim of this study was to provide a temporal and spatial description of dengue virus epidemiology in Kaohsiung City by using data for all laboratory-confirmed dengue cases during 2003–2009. We investigated age- and sex-dependent incidence rates and the spatiotemporal patterns of all cases confirmed through passive or active surveillance. Elderly persons were at particularly high risk for dengue virus–related sickness and death. Of all confirmed cases, ?75% were detected through passive surveillance activities; case-patients detected through active surveillance included immediate family members, neighbors, and colleagues of confirmed case-patients. Changing patterns of case clustering could be due to the effect of unmeasured environmental and demographic factors. PMID:23017369

  7. Effect of community participation on household environment to mitigate dengue transmission in Thailand.

    PubMed

    Suwannapong, N; Tipayamongkholgul, M; Bhumiratana, A; Boonshuyar, C; Howteerakul, N; Poolthin, S

    2014-03-01

    Due to the absence of dengue vaccination, vector control is the only measure to prevent dengue outbreaks. The key element of dengue prevention is to eliminate vector habitats. Clean household environment, preventive behaviors of household members and community participation in dengue prevention and control are key successful elements. This study aimed to investigate the associations between environmental factors, dengue knowledge, perception and preventive behaviors of household and collaboration of community members and household risk of dengue by using mixed methods. One dengue epidemic province was selected from each region of Thailand including Bangkok. Two districts, one from the highest and another from the lowest dengue incidence areas, were selected from those provinces. The household leaders, community members, and local authorities in highest dengue incidence areas were interviewed by using questionnaire and through group interviews. The environment of each selected household was observed. Of 4,561 households, 194 were reported having dengue case(s) in the past year and that outdoor solid waste disposal significantly influenced household risk of dengue (OR=1.62; 95% CI=1.16-2.29). In contrast, having gardening areas reduced dengue risk at household level by 32%. High level of community participation in dengue prevention and control in uninfected areas and the information from local authorities and community members reconfirmed that community participation was the key factor against dengue outbreaks. Sustainable process of encouraging community members to eliminate vector breeding sites such as outdoor solid waste disposal is likely to lead to an achievement in dengue prevention and control. PMID:24862055

  8. 75 FR 34146 - Draft Guideline for the Prevention and Control of Norovirus Gastroenteritis Outbreaks in...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-16

    ...Norovirus Gastroenteritis Outbreaks in Healthcare Settings AGENCY: Centers for Disease...Norovirus Gastroenteritis Outbreaks in Healthcare Settings, available on the following...use by infection prevention staff, healthcare epidemiologists, healthcare...

  9. Assessing Positivity and Circulating Levels of NS1 in Samples from a 2012 Dengue Outbreak in Rio de Janeiro, Brazil

    PubMed Central

    Allonso, Diego; Meneses, Marcelo D. F.; Fernandes, Carlos A.; Ferreira, Davis F.; Mohana-Borges, Ronaldo

    2014-01-01

    Dengue virus (DENV) represents a major threat to public health worldwide. Early DENV diagnosis should not only detect the infection but also identify patients with a higher likelihood to develop severe cases. Previous studies have suggested the potential for NS1 to serve as a viral marker for dengue severity. However, further studies using different sera panels are required to confirm this hypothesis. In this context, we developed a lab-based ELISA to detect and quantitate NS1 protein from the four DENV serotypes and from primary and secondary cases. This approach was used to calculate the circulating NS1 concentration in positive samples. We also tested the NS1 positivity of DENV-positive samples according to the Platelia Dengue NS1 Ag assay. A total of 128 samples were positive for DENV infection and were classified according to the WHO guidelines. The overall NS1 positivity was 68% according to the Platelia assay, whereas all samples were NS1-positive when analyzed with our lab-based ELISA. Fifty-four samples were positive by PCR, revealing a co-circulation of DENV1 and DENV4, and the NS1 positivity for DENV4 samples was lower than that for DENV1. The circulating NS1 concentration ranged from 7 to 284 ng/mL. Our results support previous data indicating the low efficiency of the Platelia assay to detect DENV4 infection. Moreover, this work is the first to analyze NS1 antigenemia using retrospective samples from a Brazilian outbreak. PMID:25412084

  10. Emergence of dengue virus 4 genotype II in Guangzhou, China, 2010: Survey and molecular epidemiology of one community outbreak

    PubMed Central

    2012-01-01

    Background The re-emergence of dengue virus 4 (DENV-4) has become a public health concern in South America, Southeast Asia and South Asia. However, it has not been known to have caused a local outbreak in China for the past 20 years. The purpose of this study was to elucidate the epidemiology of one local community outbreak caused by DENV-4 in Guangzhou city, China, in 2010; and to determine the molecular characteristics of the genotype II virus involved. Case presentations During September and October of 2010, one imported case, a Guangzhou resident who travelled back from Thailand, resulted in 18 secondary autochthonous cases in Guangzhou City, with an incidence rate of 5.53 per 10,000 residents. In indigenous cases, 14 serum samples tested positive for IgM against DENV and 7 for IgG from a total of 15 submitted serum samples, accompanied by 5 DENV-4 isolates. With identical envelope gene nucleotide sequences, the two isolates (D10168-GZ from the imported index case and Guangzhou 10660 from the first isolate in the autochthonous cases) were grouped into DENV-4 genotype II after comparison to 32 previous DENV-4 isolates from GenBank that originated from different areas. Conclusions Based on epidemiological and phylogenetic analyses, the outbreak, which was absent for 20 years after the DENV-4 genotype I outbreak in 1990, was confirmed as DENV-4 genotype II and initially traced to the imported index case, a Guangzhou resident who travelled back from Thailand. PMID:22497881

  11. Management of animal botulism outbreaks: from clinical suspicion to practical countermeasures to prevent or minimize outbreaks.

    PubMed

    Anniballi, Fabrizio; Fiore, Alfonsina; Löfström, Charlotta; Skarin, Hanna; Auricchio, Bruna; Woudstra, Cédric; Bano, Luca; Segerman, Bo; Koene, Miriam; Båverud, Viveca; Hansen, Trine; Fach, Patrick; Tevell Aberg, Annica; Hedeland, Mikael; Olsson Engvall, Eva; De Medici, Dario

    2013-09-01

    Botulism is a severe neuroparalytic disease that affects humans, all warm-blooded animals, and some fishes. The disease is caused by exposure to toxins produced by Clostridium botulinum and other botulinum toxin-producing clostridia. Botulism in animals represents a severe environmental and economic concern because of its high mortality rate. Moreover, meat or other products from affected animals entering the food chain may result in a public health problem. To this end, early diagnosis is crucial to define and apply appropriate veterinary public health measures. Clinical diagnosis is based on clinical findings eliminating other causes of neuromuscular disorders and on the absence of internal lesions observed during postmortem examination. Since clinical signs alone are often insufficient to make a definitive diagnosis, laboratory confirmation is required. Botulinum antitoxin administration and supportive therapies are used to treat sick animals. Once the diagnosis has been made, euthanasia is frequently advisable. Vaccine administration is subject to health authorities' permission, and it is restricted to a small number of animal species. Several measures can be adopted to prevent or minimize outbreaks. In this article we outline all phases of management of animal botulism outbreaks occurring in wet wild birds, poultry, cattle, horses, and fur farm animals. PMID:23971806

  12. Historical Compilation and Georeferencing of Dengue and Chikungunya outbreak data for Disease Modeling

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  13. Dengue Virus 2 American-Asian Genotype Identified during the 2006/2007 Outbreak in Piauí, Brazil Reveals a Caribbean Route of Introduction and Dissemination of Dengue Virus in Brazil

    PubMed Central

    Barcelos Figueiredo, Leandra; Sakamoto, Tetsu; Leomil Coelho, Luiz Felipe; de Oliveira Rocha, Eliseu Soares; Gomes Cota, Marcela Menezes; Ferreira, Gustavo Portela; de Oliveira, Jaquelline Germano; Kroon, Erna Geessien

    2014-01-01

    Dengue virus (DENV) is the most widespread arthropod-borne virus, and the number and severity of outbreaks has increased worldwide in recent decades. Dengue is caused by DENV-1, DENV- 2, DENV-3 and DENV-4 which are genetically distant. The species has been subdivided into genotypes based on phylogenetic studies. DENV-2, which was isolated from dengue fever patients during an outbreak in Piaui, Brazil in 2006/2007 was analyzed by sequencing the envelope (E) gene. The results indicated a high similarity among the isolated viruses, as well as to other DENV-2 from Brazil, Central America and South America. A phylogenetic and phylogeographic analysis based on DENV-2E gene sequences revealed that these viruses are grouped together with viruses of the American-Asian genotype in two distinct lineages. Our results demonstrate the co-circulation of two American-Asian genotype lineages in northeast Brazil. Moreover, we reveal that DENV-2 lineage 2 was detected in Piauí before it disseminated to other Brazilian states and South American countries, indicating the existence of a new dissemination route that has not been previously described. PMID:25127366

  14. Varicella outbreak in a daycare: challenges and opportunities for preventing varicella outbreaks in this setting.

    PubMed

    Daskalaki, Irini; Thermitus, Rodrerica; Perella, Dana; Viner, Kendra; Spells, Niya; Mohanty, Salini; Lopez, Adriana; Johnson, Caroline

    2014-04-01

    As a result of single-dose varicella vaccination, daycare outbreaks have become rare. We investigated a daycare outbreak resulting from a misdiagnosed varicella case in an unvaccinated attendee. Of 25 attendees aged 12-32 months without evidence of immunity, 7 (28%) were unvaccinated due to religious/philosophical opposition or recent 1st birthday. Single-dose vaccination reduced disease by 92% compared with no vaccination. PMID:24136372

  15. Outbreak!

    NSDL National Science Digital Library

    Geoffrey Battle Smith

    2004-09-01

    Outbreak! is an online, interactive educational game that helps students and teachers learn and evaluate clinical microbiology skills. When the game was used in introductory microbiology laboratories, qualitative evaluation by students showed very positiv

  16. CD8+ T cells prevent antigen-induced antibody-dependent enhancement of dengue disease in mice.

    PubMed

    Zellweger, Raphaël M; Eddy, William E; Tang, William W; Miller, Robyn; Shresta, Sujan

    2014-10-15

    Dengue virus (DENV) causes pathologies ranging from the febrile illness dengue fever to the potentially lethal severe dengue disease. A major risk factor for developing severe dengue disease is the presence of subprotective DENV-reactive Abs from a previous infection (or from an immune mother), which can induce Ab-dependent enhancement of infection (ADE). However, infection in the presence of subprotective anti-DENV Abs does not always result in severe disease, suggesting that other factors influence disease severity. In this study we investigated how CD8(+) T cell responses influence the outcome of Ab-mediated severe dengue disease. Mice were primed with aluminum hydroxide-adjuvanted UV-inactivated DENV prior to challenge with DENV. Priming failed to induce robust CD8(+) T cell responses, and it induced nonneutralizing Ab responses that increased disease severity upon infection. Transfer of exogenous DENV-activated CD8(+) T cells into primed mice prior to infection prevented Ab-dependent enhancement and dramatically reduced viral load. Our results suggest that in the presence of subprotective anti-DENV Abs, efficient CD8(+) T cell responses reduce the risk of Ab-mediated severe dengue disease. PMID:25217165

  17. Post-infectious fatigue syndrome in dengue infection

    Microsoft Academic Search

    Raymond C. S. Seet; Amy M. L. Quek; Erle C. H. Lim

    2007-01-01

    Background: Although the acute manifestations of dengue are well known, few studies have assessed the long-term consequences of dengue infection. We prospectively studied the incidence and factors associated with fatigue in a cohort of patients following dengue infection. Methods: We included patients with serologically confirmed dengue infection admitted to the National University Hospital, Singapore, during a dengue outbreak from October-November

  18. Dengue Surveillance in Veterans Affairs Healthcare Facilities, 2007–2010

    PubMed Central

    Schirmer, Patricia L.; Lucero-Obusan, Cynthia A.; Benoit, Stephen R.; Santiago, Luis M.; Stanek, Danielle; Dey, Achintya; Martinez, Mirsonia; Oda, Gina; Holodniy, Mark

    2013-01-01

    Background Although dengue is endemic in Puerto Rico (PR), 2007 and 2010 were recognized as epidemic years. In the continental United States (US), outside of the Texas-Mexico border, there had not been a dengue outbreak since 1946 until dengue re-emerged in Key West, Florida (FL), in 2009–2010. The objective of this study was to use electronic and manual surveillance systems to identify dengue cases in Veterans Affairs (VA) healthcare facilities and then to clinically compare dengue cases in Veterans presenting for care in PR and in FL. Methodology Outpatient encounters from 1/2007–12/2010 and inpatient admissions (only available from 10/2009–12/2010) with dengue diagnostic codes at all VA facilities were identified using VA's Electronic Surveillance System for Early Notification of Community-based Epidemics (ESSENCE). Additional case sources included VA data from Centers for Disease Control and Prevention BioSense and VA infection preventionists. Case reviews were performed. Categorical data was compared using Mantel-Haenszel or Fisher Exact tests and continuous variables using t-tests. Dengue case residence was mapped. Findings Two hundred eighty-eight and 21 PR and FL dengue cases respectively were identified. Of 21 FL cases, 12 were exposed in Key West and 9 were imported. During epidemic years, FL cases had significantly increased dengue testing and intensive care admissions, but lower hospitalization rates and headache or eye pain symptoms compared to PR cases. There were no significant differences in clinical symptoms, laboratory abnormalities or outcomes between epidemic and non-epidemic year cases in FL and PR. Confirmed/probable cases were significantly more likely to be hospitalized and have thrombocytopenia or leukopenia compared to suspected cases. Conclusions Dengue re-introduction in the continental US warrants increased dengue surveillance and education in VA. Throughout VA, under-testing of suspected cases highlights the need to emphasize use of diagnostic testing to better understand the magnitude of dengue among Veterans. PMID:23516642

  19. Dengue: a continuing global threat

    PubMed Central

    Guzman, Maria G.; Halstead, Scott B.; Artsob, Harvey; Buchy, Philippe; Farrar, Jeremy; Gubler, Duane J.; Hunsperger, Elizabeth; Kroeger, Axel; Margolis, Harold S.; Martínez, Eric; Nathan, Michael B.; Pelegrino, Jose Luis; Simmons, Cameron; Yoksan, Sutee; Peeling, Rosanna W.

    2014-01-01

    Dengue fever and dengue haemorrhagic fever are important arthropod-borne viral diseases. Each year, there are ~50 million dengue infections and ~500,000 individuals are hospitalized with dengue haemorrhagic fever, mainly in Southeast Asia, the Pacific and the Americas. Illness is produced by any of the four dengue virus serotypes. A global strategy aimed at increasing the capacity for surveillance and outbreak response, changing behaviours and reducing the disease burden using integrated vector management in conjunction with early and accurate diagnosis has been advocated. Antiviral drugs and vaccines that are currently under development could also make an important contribution to dengue control in the future. PMID:21079655

  20. Use of Insecticide-Treated School Uniforms for Prevention of Dengue in Schoolchildren: A Cost-Effectiveness Analysis

    PubMed Central

    Tozan, Yesim; Ratanawong, Pitcha; Louis, Valérie R.; Kittayapong, Pattamaporn; Wilder-Smith, Annelies

    2014-01-01

    Background Dengue-related illness is a leading cause of hospitalization and death, particularly among children. Practical, acceptable and affordable measures are urgently needed to protect this age group. Schools where children spend most of their day is proposed as an ideal setting to implement preventive strategies against day-biting Aedes mosquitoes. The use of insecticide-treated school uniforms is a promising strategy currently under investigation. Methods Using a decision-analytic model, we evaluated the cost-effectiveness of the use of insecticide-treated school uniforms for prevention of dengue, compared with a “do-nothing” alternative, in schoolchildren from the societal perspective. We explored how the potential economic value of the intervention varied under various scenarios of intervention effectiveness and cost, as well as dengue infection risk in school-aged children, using data specific to Thailand. Results At an average dengue incidence rate of 5.8% per year in school-aged children, the intervention was cost-effective (ICER?$16,440) in a variety of scenarios when the intervention cost per child was $5.3 or less and the intervention effectiveness was 50% or higher. In fact, the intervention was cost saving (ICER<0) in all scenarios in which the intervention cost per child was $2.9 or less per year and the intervention effectiveness was 50% or higher. The results suggested that this intervention would be of no interest to Thai policy makers when the intervention cost per child was $10.6 or higher per year regardless of intervention effectiveness (ICER>$16,440). Conclusions Our results present the potential economic value of the use of insecticide-treated uniforms for prevention of dengue in schoolchildren in a typical dengue endemic setting and highlight the urgent need for additional research on this intervention. PMID:25247556

  1. Dengue viral infections

    PubMed Central

    Malavige, G; Fernando, S; Fernando, D; Seneviratne, S

    2004-01-01

    Dengue viral infections are one of the most important mosquito borne diseases in the world. They may be asymptomatic or may give rise to undifferentiated fever, dengue fever, dengue haemorrhagic fever (DHF), or dengue shock syndrome. Annually, 100 million cases of dengue fever and half a million cases of DHF occur worldwide. Ninety percent of DHF subjects are children less than 15 years of age. At present, dengue is endemic in 112 countries in the world. No vaccine is available for preventing this disease. Early recognition and prompt initiation of appropriate treatment are vital if disease related morbidity and mortality are to be limited. This review outlines aspects of the epidemiology of dengue infections, the dengue virus and its mosquito vector, clinical features and pathogenesis of dengue infections, and the management and control of these infections. PMID:15466994

  2. Managing and preventing outbreaks of Gram-negative infections in UK neonatal units.

    PubMed

    Anthony, Mark; Bedford-Russell, Alison; Cooper, Tracey; Fry, Carole; Heath, Paul T; Kennea, Nigel; McCartney, Maureen; Patel, Bharat; Pollard, Tina; Sharland, Mike; Wilson, Peter

    2013-11-01

    De novo guidance on the management of Gram-negative bacteria outbreaks in UK neonatal units was developed in 2012 by a Department of Health, England Antimicrobial Resistance and Healthcare Associated Infection working group. The recommendations included activation of an organisational response and establishing a control team when an outbreak is suspected; screening for the specific organism only during an outbreak; undertaking multidisciplinary reviews of cleaning routines, hand hygiene and Gram-negative bacteria transmission risks; considering deep-cleaning; cohorting colonised and infected babies preferably but not necessarily in isolation cubicles; and considering reducing beds or closing a unit to new admissions as a way of improving spacing and staff:patient ratios until the outbreak is under control. The group advised establishing mechanisms to communicate effectively across the network; informing parents of the outbreak as early as possible, and providing prewritten 'infection outbreak' information sheets. For prevention of outbreaks, the group advised meeting national staffing and cot-spacing requirements; following a Water Action Plan; using infection reduction care bundles and benchmarking; and introducing breast milk early and limiting antibiotic use. PMID:23792354

  3. Transmission-Blocking Antibodies against Mosquito C-Type Lectins for Dengue Prevention

    PubMed Central

    Liu, Yang; Zhang, Fuchun; Liu, Jianying; Xiao, Xiaoping; Zhang, Siyin; Qin, Chengfeng; Xiang, Ye; Wang, Penghua; Cheng, Gong

    2014-01-01

    C-type lectins are a family of proteins with carbohydrate-binding activity. Several C-type lectins in mammals or arthropods are employed as receptors or attachment factors to facilitate flavivirus invasion. We previously identified a C-type lectin in Aedes aegypti, designated as mosquito galactose specific C-type lectin-1 (mosGCTL-1), facilitating the attachment of West Nile virus (WNV) on the cell membrane. Here, we first identified that 9 A. aegypti mosGCTL genes were key susceptibility factors facilitating DENV-2 infection, of which mosGCTL-3 exhibited the most significant effect. We found that mosGCTL-3 was induced in mosquito tissues with DENV-2 infection, and that the protein interacted with DENV-2 surface envelop (E) protein and virions in vitro and in vivo. In addition, the other identified mosGCTLs interacted with the DENV-2 E protein, indicating that DENV may employ multiple mosGCTLs as ligands to promote the infection of vectors. The vectorial susceptibility factors that facilitate pathogen invasion may potentially be explored as a target to disrupt the acquisition of microbes from the vertebrate host. Indeed, membrane blood feeding of antisera against mosGCTLs dramatically reduced mosquito infective ratio. Hence, the immunization against mosGCTLs is a feasible approach for preventing dengue infection. Our study provides a future avenue for developing a transmission-blocking vaccine that interrupts the life cycle of dengue virus and reduces disease burden. PMID:24550728

  4. Large Outbreak Caused by Methicillin Resistant Staphylococcus pseudintermedius ST71 in a Finnish Veterinary Teaching Hospital – From Outbreak Control to Outbreak Prevention

    PubMed Central

    Grönthal, Thomas; Moodley, Arshnee; Nykäsenoja, Suvi; Junnila, Jouni; Guardabassi, Luca; Thomson, Katariina; Rantala, Merja

    2014-01-01

    Introduction The purpose of this study was to describe a nosocomial outbreak caused by methicillin resistant Staphylococcus pseudintermedius (MRSP) ST71 SCCmec II-III in dogs and cats at the Veterinary Teaching Hospital of the University of Helsinki in November 2010 – January 2012, and to determine the risk factors for acquiring MRSP. In addition, measures to control the outbreak and current policy for MRSP prevention are presented. Methods Data of patients were collected from the hospital patient record software. MRSP surveillance data were acquired from the laboratory information system. Risk factors for MRSP acquisition were analyzed from 55 cases and 213 controls using multivariable logistic regression in a case-control study design. Forty-seven MRSP isolates were analyzed by pulsed field gel electrophoresis and three were further analyzed with multi-locus sequence and SCCmec typing. Results Sixty-three MRSP cases were identified, including 27 infections. MRSPs from the cases shared a specific multi-drug resistant antibiogram and PFGE-pattern indicated clonal spread. Four risk factors were identified; skin lesion (OR?=?6.2; CI95% 2.3–17.0, P?=?0.0003), antimicrobial treatment (OR?=?3.8, CI95% 1.0–13.9, P?=?0.0442), cumulative number of days in the intensive care unit (OR?=?1.3, CI95% 1.1–1.6, P?=?0.0007) or in the surgery ward (OR?=?1.1, CI95% 1.0–1.3, P?=?0.0401). Tracing and screening of contact patients, enhanced hand hygiene, cohorting and barrier nursing, as well as cleaning and disinfection were used to control the outbreak. To avoid future outbreaks and spread of MRSP a search-and-isolate policy was implemented. Currently nearly all new MRSP findings are detected in screening targeted to risk patients on admission. Conclusion Multidrug resistant MRSP is capable of causing a large outbreak difficult to control. Skin lesions, antimicrobial treatment and prolonged hospital stay increase the probability of acquiring MRSP. Rigorous control measures were needed to control the outbreak. We recommend the implementation of a search-and-isolate policy to reduce the burden of MRSP. PMID:25333798

  5. Dengue Prevention

    MedlinePLUS

    ... water containers like pet and animal watering containers, flower planter dishes or cover water storage barrels. Look ... water indoors such as in vases with fresh flowers and clean at least once a week. The ...

  6. Clinical, Molecular, and Epidemiological Analysis of Dengue Cases during a Major Outbreak in the Midwest Region of Minas Gerais, Brazil

    PubMed Central

    Braga, Juliana Cristina Duarte; da Silva, Leandro César; Tibúrcio, Jacqueline Domingues; Silva, Mirna de Abreu e; Pereira, Lailah Horácio Sales; Dutra, Karina Rocha; Ferreira, Jaqueline Maria Siqueira; Lopes, Débora de Oliveira; dos Santos, Luciana Lara

    2014-01-01

    This study aims to perform the first molecular and clinical-epidemiological analysis of dengue cases in Divinopolis, MG, Brazil. Data from 4,110 cases of dengue were accessed and 190 clinical samples were collected for molecular analyses. In this study, 2.7% of the men and 3.0% of the women were admitted to hospital. There was no association between gender and hospital admission. The symptoms observed in this study are according to the Health Ministry, but fever was present in 82.2% and not in 100% of cases. The chance of hospital admission was 1.55 higher in patients with any kind of bleeding (334) and 2.4% of individuals without bleeding were also hospitalized due to other warning signs. In the molecular analyses, 23% of the samples were positive for DENV. DENV-2 and DENV-3 were identified in 2010, DENV-3 in 2011, DENV-1 in 2012, and DENV-1 and DENV-4 in 2013. DENV detection was possible in samples with only one day of symptoms. This first report of dengue data in Divinópolis provided more insight into the viral types and effects of disease in the city, confirming the need for caution in assessing cases of suspected dengue and for revision of the criteria proposed by the Health Ministry to classify cases of the disease. PMID:25120572

  7. Spatial, environmental and entomological risk factors analysis on a rural dengue outbreak in Lundu District in Sarawak, Malaysia.

    PubMed

    Cheah, Whye Lian; Chang, Moh Seng; Wang, Yin Chai

    2006-06-01

    The objective of this study was to elucidate the association of various risk factors with dengue cases reported in Lundu district, Sarawak, by analyzing the interaction between environmental, entomological, socio-demographic factors. Besides conventional entomological, serological and house surveys, this study also used GIS technology to generate geographic and environmental data on Aedes albopictus and dengue transmission. Seven villages were chosen based on the high number of dengue cases reported. A total of 551 households were surveyed. An overall description of the socio-demographic background and basic facilities was presented together with entomological and geographical profiles. For serological and ovitrap studies, systematic random sampling was used. Serological tests indicated that 23.7% of the 215 samples had a history of dengue, either recent or previous infections. Two samples (0.9%) were confirmed by IgM ELISA and 49 samples (22.8%) had IgG responses. A total of 32,838 Aedes albopictus eggs were collected in 56 days of trapping. Cluster sampling was also done to determine whether any of the risk factors (entomological or geographical) were influenced by geographical location. These clusters were defined as border villages with East Kalimantan and roadside villages along Lundu/Biawas trunk road. The data collected were analyzed using SPSS version 10.01. Descriptive analysis using frequency, means, and median were used. To determine the association between variables and dengue cases reported, and to describe the differences between the two clusters of villages, two-sample t-test, and Pearson's Chi-Square were used. Accurate maps were produced with overlay and density function, which facilitates the map visualization and report generating phases. This study also highlights the use of differential Global Positioning System in mapping sites of 1m accuracy. Analysis of the data revealed there are significant differences in clusters of villages attributable to container density, house density, distance of the house from the main road, and number of Ae. albopictus eggs from ovitraps set indoor, outdoor and in dumping sites (Person's Chi-Square = 6.111, df = 1, p < 0.01). Further analysis using t-test showed that house density, container density, indoor mosquitoes egg count, outdoor mosquitoes egg count, and dumping sites mosquitoes egg count were higher at the roadside villages compared to border villages. A number of potential risk factors including those generated from GIS were investigated. None of the factors investigated in this study were associated with the dengue cases reported. PMID:17041556

  8. Dengue virus and Japanese encephalitis virus epidemiological shifts in Nepal: a case of opposing trends.

    PubMed

    Dumre, Shyam P; Shakya, Geeta; Na-Bangchang, Kesara; Eursitthichai, Veerachai; Rudi Grams, Hans; Upreti, Senendra R; Ghimire, Prakash; KC, Khagendra; Nisalak, Ananda; Gibbons, Robert V; Fernandez, Stefan

    2013-04-01

    We report on the changing epidemiology of two important flaviviruses in Nepal: Japanese encephalitis (JE) and dengue viruses. Morbidity and mortality in Nepal is in the thousands since JE was introduced in 1978. Nepal launched an extensive laboratory-based JE surveillance in 2004. Nepal experienced a remarkable reduction in disease burden after mass immunizations from 2005 to 2010, when 2,040 JE infections and 205 JE-related deaths were confirmed. With its emergence in 2006, dengue has become a significant challenge in the country, highlighted by a sudden outbreak in 2010 that resulted in 359 confirmed dengue infections. Currently, both viruses cocirculate in Nepal. Here, we document the remarkable expansion of dengue in Nepal, which urgently requires national surveillance to refine the burden and make recommendations regarding control and prevention programs. We believe that the use of existing JE surveillance network for integrated dengue surveillance may represent the most appropriate alternative. PMID:23419366

  9. Time series analysis of dengue incidence in Guadeloupe, French West Indies: Forecasting models using climate variables as predictors

    PubMed Central

    2011-01-01

    Background During the last decades, dengue viruses have spread throughout the Americas region, with an increase in the number of severe forms of dengue. The surveillance system in Guadeloupe (French West Indies) is currently operational for the detection of early outbreaks of dengue. The goal of the study was to improve this surveillance system by assessing a modelling tool to predict the occurrence of dengue epidemics few months ahead and thus to help an efficient dengue control. Methods The Box-Jenkins approach allowed us to fit a Seasonal Autoregressive Integrated Moving Average (SARIMA) model of dengue incidence from 2000 to 2006 using clinical suspected cases. Then, this model was used for calculating dengue incidence for the year 2007 compared with observed data, using three different approaches: 1 year-ahead, 3 months-ahead and 1 month-ahead. Finally, we assessed the impact of meteorological variables (rainfall, temperature and relative humidity) on the prediction of dengue incidence and outbreaks, incorporating them in the model fitting the best. Results The 3 months-ahead approach was the most appropriate for an effective and operational public health response, and the most accurate (Root Mean Square Error, RMSE = 0.85). Relative humidity at lag-7 weeks, minimum temperature at lag-5 weeks and average temperature at lag-11 weeks were variables the most positively correlated to dengue incidence in Guadeloupe, meanwhile rainfall was not. The predictive power of SARIMA models was enhanced by the inclusion of climatic variables as external regressors to forecast the year 2007. Temperature significantly affected the model for better dengue incidence forecasting (p-value = 0.03 for minimum temperature lag-5, p-value = 0.02 for average temperature lag-11) but not humidity. Minimum temperature at lag-5 weeks was the best climatic variable for predicting dengue outbreaks (RMSE = 0.72). Conclusion Temperature improves dengue outbreaks forecasts better than humidity and rainfall. SARIMA models using climatic data as independent variables could be easily incorporated into an early (3 months-ahead) and reliably monitoring system of dengue outbreaks. This approach which is practicable for a surveillance system has public health implications in helping the prediction of dengue epidemic and therefore the timely appropriate and efficient implementation of prevention activities. PMID:21658238

  10. Prevention of Dengue Fever: An Exploratory School-Community Intervention Involving Students Empowered as Change Agents

    ERIC Educational Resources Information Center

    Jayawardene, Wasantha P.; Lohrmann, David K.; YoussefAgha, Ahmed H.; Nilwala, Dayani C.

    2011-01-01

    Background: Dengue fever and dengue hemorrhagic fever (DF/DHF) are epidemic and endemic in tropical and subtropical countries including Sri Lanka. Numerous structural and community interventions have been shown to be effective in interrupting the life cycle of mosquitoes that transmit DF/DHF; however, these interventions are not always implemented…

  11. Integrating participatory community mobilization processes to improve dengue prevention: an eco-bio-social scaling up of local success in Machala, Ecuador

    PubMed Central

    Mitchell-Foster, Kendra; Ayala, Efraín Beltrán; Breilh, Jaime; Spiegel, Jerry; Wilches, Ana Arichabala; Leon, Tania Ordóñez; Delgado, Jefferson Adrian

    2015-01-01

    Background This project investigates the effectiveness and feasibility of scaling-up an eco-bio-social approach for implementing an integrated community-based approach for dengue prevention in comparison with existing insecticide-based and emerging biolarvicide-based programs in an endemic setting in Machala, Ecuador. Methods An integrated intervention strategy (IIS) for dengue prevention (an elementary school-based dengue education program, and clean patio and safe container program) was implemented in 10 intervention clusters from November 2012 to November 2013 using a randomized controlled cluster trial design (20 clusters: 10 intervention, 10 control; 100 households per cluster with 1986 total households). Current existing dengue prevention programs served as the control treatment in comparison clusters. Pupa per person index (PPI) is used as the main outcome measure. Particular attention was paid to social mobilization and empowerment with IIS. Results Overall, IIS was successful in reducing PPI levels in intervention communities versus control clusters, with intervention clusters in the six paired clusters that followed the study design experiencing a greater reduction of PPI compared to controls (2.2 OR, 95% CI: 1.2 to 4.7). Analysis of individual cases demonstrates that consideration for contexualizing programs and strategies to local neighborhoods can be very effective in reducing PPI for dengue transmission risk reduction. Conclusions In the rapidly evolving political climate for dengue control in Ecuador, integration of successful social mobilization and empowerment strategies with existing and emerging biolarvicide-based government dengue prevention and control programs is promising in reducing PPI and dengue transmission risk in southern coastal communities like Machala. However, more profound analysis of social determination of health is called for to assess sustainability prospects. PMID:25604763

  12. Reemergence of Dengue in Mauritius

    PubMed Central

    Pursem, Vidula N.; Barkham, Timothy M.S.; Ng, Lee-Ching; Inoue, Masafumi; Manraj, Shyam S.

    2010-01-01

    Dengue reemerged in Mauritius in 2009 after an absence of >30 years, and >200 cases were confirmed serologically. Molecular studies showed that the outbreak was caused by dengue virus type 2. Phylogenetic analysis of the envelope gene identified 2 clades of the virus. No case of hemorrhagic fever was recorded. PMID:20350397

  13. The Prevalence and Endemic Nature of Dengue Infections in Guangdong, South China: An Epidemiological, Serological, and Etiological Study from 2005–2011

    PubMed Central

    Guo, Ru-ning; Lin, Jin-yan; Li, Lin-hui; Ke, Chang-wen; He, Jian-feng; Zhong, Hao-jie; Zhou, Hui-qiong; Peng, Zhi-qiang; Yang, Fen; Liang, Wen-jia

    2014-01-01

    Objectives Frequent outbreaks of dengue are considered to be associated with an increased risk for endemicity of the disease. The occurrence of a large number of indigenous dengue cases in consecutive years indicates the possibility of a changing dengue epidemic pattern in Guangdong, China. Methods To have a clear understanding of the current dengue epidemic, a retrospective study of epidemiological profile, serological response, and virological features of dengue infections from 2005–2011 was conducted. Case data were collected from the National Notifiable Infectious Diseases Reporting Network. Serum samples were collected and prepared for serological verification and etiological confirmation. Incidence, temporal and spatial distribution, and the clinical manifestation of dengue infections were analyzed. Pearson's Chi-Square test was used to compare incidences between different age groups. A seroprevalence survey was implemented in local healthy inhabitants to obtain the overall positive rate for the specific immunoglobulin (Ig) G antibody against dengue virus (DENV). Results The overall annual incidence rate was 1.87/100000. A significant difference was found in age-specific incidence (Pearson's Chi-Square value 498.008, P<0.001). Children under 5 years of age had the lowest incidence of 0.28/100000. The vast majority of cases presented with a mild manifestation typical to dengue fever. The overall seroprevalence of dengue IgG antibody in local populations was 2.43% (range 0.28%–5.42%). DENV-1 was the predominant serotype in circulation through the years, while all 4 serotypes were identified in indigenous patients from different outbreak localities since 2009. Conclusions A gradual change in the epidemic pattern of dengue infection has been observed in recent years in Guangdong. With the endemic nature of dengue infections, the transition from a monotypic to a multitypic circulation of dengue virus in the last several years will have an important bearing on the prevention and control of dengue in the province and in the neighboring districts. PMID:24465613

  14. Dengue in children.

    PubMed

    Verhagen, Lilly M; de Groot, Ronald

    2014-11-01

    Dengue is a mosquito-borne viral disease of expanding geographical range and increasing incidence. The vast majority of dengue cases are children less than 15 years of age. Dengue causes a spectrum of illness from mild fever to severe disease with plasma leakage and shock. Infants and children with secondary heterologous dengue infections are most at risk for severe dengue disease. Laboratory diagnosis of dengue can be established within five days of disease onset by direct detection of viral components in serum. After day five, serologic diagnosis provides indirect evidence of dengue. Currently, no effective antiviral agents are available to treat dengue infection. Therefore, treatment remains supportive, with emphasis on close hematological monitoring, recognition of warning signs of severe disease and fluid-replacement therapy and/or blood transfusions when required. Development of a dengue vaccine is considered a high public health priority. A safe and efficacious dengue vaccine would also be important for travelers. This review highlights the current understanding of dengue in children, including its clinical manifestations, pathogenesis, diagnostic tests, management and prevention. PMID:25225163

  15. Economic and Disease Burden of Dengue in Mexico

    PubMed Central

    Undurraga, Eduardo A.; Betancourt-Cravioto, Miguel; Ramos-Castañeda, José; Martínez-Vega, Ruth; Méndez-Galván, Jorge; Gubler, Duane J.; Guzmán, María G.; Halstead, Scott B.; Harris, Eva; Kuri-Morales, Pablo; Tapia-Conyer, Roberto; Shepard, Donald S.

    2015-01-01

    Background Dengue imposes a substantial economic and disease burden in most tropical and subtropical countries. Dengue incidence and severity have dramatically increased in Mexico during the past decades. Having objective and comparable estimates of the economic burden of dengue is essential to inform health policy, increase disease awareness, and assess the impact of dengue prevention and control technologies. Methods and Findings We estimated the annual economic and disease burden of dengue in Mexico for the years 2010–2011. We merged multiple data sources, including a prospective cohort study; patient interviews and macro-costing from major hospitals; surveillance, budget, and health data from the Ministry of Health; WHO cost estimates; and available literature. We conducted a probabilistic sensitivity analysis using Monte Carlo simulations to derive 95% certainty levels (CL) for our estimates. Results suggest that Mexico had about 139,000 (95%CL: 128,000–253,000) symptomatic and 119 (95%CL: 75–171) fatal dengue episodes annually on average (2010–2011), compared to an average of 30,941 symptomatic and 59 fatal dengue episodes reported. The annual cost, including surveillance and vector control, was US$170 (95%CL: 151–292) million, or $1.56 (95%CL: 1.38–2.68) per capita, comparable to other countries in the region. Of this, $87 (95%CL: 87–209) million or $0.80 per capita (95%CL: 0.62–1.12) corresponds to illness. Annual disease burden averaged 65 (95%CL: 36–99) disability-adjusted life years (DALYs) per million population. Inclusion of long-term sequelae, co-morbidities, impact on tourism, and health system disruption during outbreaks would further increase estimated economic and disease burden. Conclusion With this study, Mexico joins Panama, Puerto Rico, Nicaragua, and Thailand as the only countries or areas worldwide with comprehensive (illness and preventive) empirical estimates of dengue burden. Burden varies annually; during an outbreak, dengue burden may be significantly higher than that of the pre-vaccine level of rotavirus diarrhea. In sum, Mexico’s potential economic benefits from dengue control would be substantial. PMID:25786225

  16. Salmonella enteritidis outbreak in a restaurant chain: the continuing challenges of prevention.

    PubMed Central

    Vugia, D. J.; Mishu, B.; Smith, M.; Tavris, D. R.; Hickman-Brenner, F. W.; Tauxe, R. V.

    1993-01-01

    In 1990, a Salmonella enteritidis (SE) outbreak occurred in a restaurant chain in Pennsylvania. To determine its cause(s), we conducted a case-control study and a cohort study at one restaurant, and a survey of restaurants. Egg dishes were associated with illness (P = 0.03). Guests from one hotel eating at the restaurant had a diarrhoeal attack rate of 14%, 4.7-fold higher than among those not eating there (P = 0.04). There were no differences in egg handling between affected and unaffected restaurants. Eggs supplied to affected restaurants were medium grade AA eggs from a single farm, and were reportedly refrigerated during distribution. Human and hen SE isolates were phage type 8 and had similar plasmid profiles and antibiograms. We estimate the prevalence of infected eggs during the outbreak to be as high as 1 in 12. Typical restaurant egg-handling practices and refrigeration during distribution appear to be insufficient by themselves to prevent similar outbreaks. PMID:8432323

  17. Post-dengue parkinsonism

    PubMed Central

    2013-01-01

    Background Dengue is a common illness in the tropics. Equally common are neurological complications that stem from dengue infection. However, to date, parkinsonism following dengue has not been reported in medical literature. Case presentation A previously well 18-year old man developed parkinsonism, in addition to other neurological symptoms following serologically confirmed dengue fever. Alternative etiologies were excluded by way of imaging and blood investigations. Conclusions The authors detail the first reported case of parkinsonism complicating dengue fever. Keeping rare presentations of common illnesses in mind, it behoves clinicians to consider parkinsonism as a complication following dengue infection. This would prevent injudicious treatment with L-dopa and dopamine agonists. Immunosuppression with steroids has been shown to be helpful in certain cases. PMID:23594500

  18. [Dengue outbreak by virus type 4 in French Polynesia. II. Preliminary biological observations on epidemiology and physiopathology of the disease (author's transl)].

    PubMed

    Parc, F; Tetaria, C; Pichon, G

    1981-01-01

    Authors report some accurate epidemiologic and physiopathologic data about dengue 4. Thanks to virus intrathoracic inoculation in Toxorhynchites amboinensis (Doleshall, 1857), 202 viral strains have been isolated from 633 sera samples. The incidence of the disease has decreased very early after immunization of the whole population and resulted in an eradication of dengue type 1 virus which was endemic in French Polynesia since 1976. Only one type of dengue virus seems to be tolerated in French Polynesian ecosystem in the same time. There is no crossing protection with dengue 1. Clinically, the picture has been the same in both new and previously infected by dengue 1 patients. Duration of viremia during the secondary dengue fever is not shorter than in the primary one. The hemagglutination inhibiting antibodies do not protect patients, but do not result in immune-complexes pathology. PMID:7278575

  19. Public knowledge and preventive behavior during a large-scale Salmonella outbreak: results from an online survey in the Netherlands

    PubMed Central

    2014-01-01

    Background Food-borne Salmonella infections are a worldwide concern. During a large-scale outbreak, it is important that the public follows preventive advice. To increase compliance, insight in how the public gathers its knowledge and which factors determine whether or not an individual complies with preventive advice is crucial. Methods In 2012, contaminated salmon caused a large Salmonella Thompson outbreak in the Netherlands. During the outbreak, we conducted an online survey (n?=?1,057) to assess the general public’s perceptions, knowledge, preventive behavior and sources of information. Results Respondents perceived Salmonella infections and the 2012 outbreak as severe (m?=?4.21; five-point scale with 5 as severe). Their knowledge regarding common food sources, the incubation period and regular treatment of Salmonella (gastro-enteritis) was relatively low (e.g., only 28.7% knew that Salmonella is not normally treated with antibiotics). Preventive behavior differed widely, and the majority (64.7%) did not check for contaminated salmon at home. Most information about the outbreak was gathered through traditional media and news and newspaper websites. This was mostly determined by time spent on the medium. Social media played a marginal role. Wikipedia seemed a potentially important source of information. Conclusions To persuade the public to take preventive actions, public health organizations should deliver their message primarily through mass media. Wikipedia seems a promising instrument for educating the public about food-borne Salmonella. PMID:24479614

  20. Investigating an outbreak of acute fever in Chuuk, Federated States of Micronesia

    PubMed Central

    Yichiro, Yoster; Otoko, Kasian; Heldart, Helden; Meyshine, Andita; Assito, Prisca; Pretrick, Moses; Souares, Yvan; Hancock, Thane; Durand, Mark; Roth, Adam

    2014-01-01

    Objective In September 2012, there was an unexpected increase of acute febrile illness (AFI) in Chuuk State of the Federated States of Micronesia. At the same time, dengue outbreaks were occurring in two of the Federated States of Micronesia’s other three states. The cause of AFI was suspected to be dengue; however, by the end of October, only one of 39 samples was positive for dengue. The objective of the investigation was to establish the cause of the outbreak. Methods A line list was created and data analysed by time, place, person and clinical features. Reported symptoms were compared with the published symptoms of several diagnoses and laboratory testing undertaken. Results Of the 168 suspected cases, 62% were less than 20 years of age and 60% were male. The clinical features of the cases were not typical for dengue but suggestive of respiratory illness. Nasopharyngeal swabs were subsequently collected and found to be positive for influenza. Public health measures were undertaken and the AFI returned to expected levels. Discussion Clinical diagnosis of acute febrile illness (AFI) can often be difficult and misleading. This can mean that opportunities for preventive measures early on in an outbreak are missed. In any outbreak, descriptive epidemiological analyses are valuable in helping to ascertain the cause of the outbreak. PMID:25685599

  1. Improved dengue fever prevention through innovative intervention methods in the city of Salto, Uruguay

    PubMed Central

    Basso, César; García da Rosa, Elsa; Romero, Sonnia; González, Cristina; Lairihoy, Rosario; Roche, Ingrid; Caffera, Ruben M.; da Rosa, Ricardo; Calfani, Marisel; Alfonso-Sierra, Eduardo; Petzold, Max; Kroeger, Axel; Sommerfeld, Johannes

    2015-01-01

    Background Uruguay is located at the southern border of Aedes aegypti distribution on the South American sub-continent. The reported dengue cases in the country are all imported from surrounding countries. One of the cities at higher risk of local dengue transmission is Salto, a border city with heavy traffic from dengue endemic areas. Methods We completed an intervention study using a cluster randomized trial design in 20 randomly selected ‘clusters’ in Salto. The clusters were located in neighborhoods of differing geography and economic, cultural and social aspects. Results Entomological surveys were carried out to measure the impact of the intervention on vector densities. Through participatory processes of all stakeholders, an appropriate ecosystem management intervention was defined. Residents collected the abundant small water holding containers and the Ministry of Public Health and the Municipality of Salto were responsible for collecting and eliminating them. Additional vector breeding places were large water tanks; they were either altered so that they could not hold water any more or covered so that oviposition by mosquitoes could not take place. Conclusions The response from the community and national programme managers was encouraging. The intervention evidenced opportunities for cost savings and reducing dengue vector densities (although not to statistically significant levels). The observed low vector density limits the potential reduction due to the intervention. A larger sample size is needed to obtain a statistically significant difference. PMID:25604764

  2. A spatiotemporal dengue fever early warning model accounting for nonlinear associations with meteorological factors: a Bayesian maximum entropy approach

    NASA Astrophysics Data System (ADS)

    Lee, Chieh-Han; Yu, Hwa-Lung; Chien, Lung-Chang

    2014-05-01

    Dengue fever has been identified as one of the most widespread vector-borne diseases in tropical and sub-tropical. In the last decade, dengue is an emerging infectious disease epidemic in Taiwan especially in the southern area where have annually high incidences. For the purpose of disease prevention and control, an early warning system is urgently needed. Previous studies have showed significant relationships between climate variables, in particular, rainfall and temperature, and the temporal epidemic patterns of dengue cases. However, the transmission of the dengue fever is a complex interactive process that mostly understated the composite space-time effects of dengue fever. This study proposes developing a one-week ahead warning system of dengue fever epidemics in the southern Taiwan that considered nonlinear associations between weekly dengue cases and meteorological factors across space and time. The early warning system based on an integration of distributed lag nonlinear model (DLNM) and stochastic Bayesian Maximum Entropy (BME) analysis. The study identified the most significant meteorological measures including weekly minimum temperature and maximum 24-hour rainfall with continuous 15-week lagged time to dengue cases variation under condition of uncertainty. Subsequently, the combination of nonlinear lagged effects of climate variables and space-time dependence function is implemented via a Bayesian framework to predict dengue fever occurrences in the southern Taiwan during 2012. The result shows the early warning system is useful for providing potential outbreak spatio-temporal prediction of dengue fever distribution. In conclusion, the proposed approach can provide a practical disease control tool for environmental regulators seeking more effective strategies for dengue fever prevention.

  3. Outbreak of Escherichia coli O157 in a nursery: lessons for prevention

    PubMed Central

    Al-Jader, L; Salmon, R; Walker, A; Williams, H; Willshaw, G; Cheasty, T

    1999-01-01

    OBJECTIVES—To identify risk factors for transmission of verocytotoxin producing Escherichia coli O157 (VTECO157) and means of prevention.?STUDY DESIGN—Outbreak investigation: retrospective cohort study.?SETTING—A nursery (child care centre) in North Wales.?SUBJECTS—Children attending (n = 104).?METHODS—Faeces were examined using sorbitol MacConkey agar (SMAC), with cefixime, tellurite, and rhamnose; enrichment in modified tryptone soya broth; and immunomagnetic separation. Symptoms and exposure data were obtained from questionnaires to parents/guardians and children's toiletting and feeding records kept at the nursery.?MAIN OUTCOME MEASURE—A "case" was defined as a child with verocytotoxin producing E coli O157 isolated from faeces, or a history of haemolytic uraemic syndrome (HUS) and antibodies to E coli O157 lipopolysaccharide, during the period 10 August to 30 September 1995.?RESULTS—The attack rate was 31 in 104. Two children developed HUS. There were higher attack rates among girls and friends who played together. Cases were more likely to attend the nursery more frequently. The mean number of recorded bowel motions/child/half day was 0.51in cases and 0.21 in well children. Child to staff ratios were high preceding and during the outbreak.?CONCLUSIONS—A sick child is the most plausible source of infection with subsequent person to person transmission. The record of children's toiletting discriminated between cases and well children and might have allowed earlier detection of the outbreak. This simple record could be considered by other child care facilities as a means of giving early warning of problems with infectious intestinal diseases.?? PMID:10373138

  4. Dengue Fever

    MedlinePLUS

    ... help lower the chances of infection. About Dengue Fever Dengue (DEN-gee) fever is caused by four similar viruses spread by ... else, that person can be infected with dengue fever. The virus can't spread directly from person ...

  5. Lethal Antibody Enhancement of Dengue Disease in Mice Is Prevented by Fc Modification

    Microsoft Academic Search

    Scott J. Balsitis; Katherine L. Williams; Ruben Lachica; Diana Flores; Jennifer L. Kyle; Erin Mehlhop; Syd Johnson; Michael S. Diamond; P. Robert Beatty; Eva Harris

    2010-01-01

    Immunity to one of the four dengue virus (DV) serotypes can increase disease severity in humans upon subsequent infection with another DV serotype. Serotype cross-reactive antibodies facilitate DV infection of myeloid cells in vitro by promoting virus entry via Fc? receptors (Fc?R), a process known as antibody-dependent enhancement (ADE). However, despite decades of investigation, no in vivo model for antibody

  6. Flavonoid from Carica papaya inhibits NS2B-NS3 protease and prevents Dengue 2 viral assembly

    PubMed Central

    Senthilvel, Padmanaban; Lavanya, Pandian; Kumar, Kalavathi Murugan; Swetha, Rayapadi; Anitha, Parimelzaghan; Bag, Susmita; Sarveswari, Sundaramoorthy; Vijayakumar, Vijayaparthasarathi; Ramaiah, Sudha; Anbarasu, Anand

    2013-01-01

    Dengue virus belongs to the virus family Flaviviridae. Dengue hemorrhagic disease caused by dengue virus is a public health problem worldwide. The viral non structural 2B and 3 (NS2B-NS3) protease complex is crucial for virus replication and hence, it is considered to be a good anti-viral target. Leaf extracts from Carica papaya is generally prescribed for patients with dengue fever, but there are no scientific evidences for its anti-dengue activity; hence we intended to investigate the anti-viral activity of compounds present in the leaves of Carica papaya against dengue 2 virus (DENV-2). We analysed the anti-dengue activities of the extracts from Carica papaya by using bioinformatics tools. Interestingly, we find the flavonoid quercetin with highest binding energy against NS2B-NS3 protease which is evident by the formation of six hydrogen bonds with the amino acid residues at the binding site of the receptor. Our results suggest that the flavonoids from Carica papaya have significant anti-dengue activities. Abbreviations ADME - Absorption, distribution, metabolism and excretion, BBB - Blood brain barrier, CYP - Cytochrome P450, DENV - – Dengue virus, DHF - Dengue hemorrhagic fever, DSS - Dengue shock syndrome, GCMS - – Gas chromatography- Mass spectrometry, MOLCAD - Molecular Computer Aided Design, NS - Non structural, PDB - Protein data bank, PMF - Potential Mean Force. PMID:24307765

  7. Effectiveness analysis of fumigation strategy in dengue disease prevention program (Case study: Jakarta province, Indonesia)

    NASA Astrophysics Data System (ADS)

    Agustine, D.; Mahatma, Y.; Aldila, D.

    2015-03-01

    Mathematical model of dengue disease with fumigation intervention for mosquito population will discussed in this article. Interaction between human and mosquitoes population will based on SIR-SI host-vector model. Side effect of fumigation where mosquito capable to developed a resistance to fumigation will be accommodated in to the model. Equilibrium points and basic reproductive ratio as the endemic criteria will be shown analytically. Some numerical results are shown to give a back up reasoning for analytical result. We conclude that resistance of mosquitoes to fumigation intervention play an important role in fumigation strategy.

  8. [Classical dengue transmission dynamics involving mechanical control and prophylaxis].

    PubMed

    Toro-Zapata, Hernán D; Restrepo, Leonardo D; Vergaño-Salazar, Juan G; Muñoz-Loaiza, Aníbal

    2010-12-01

    Dengue fever transmission dynamics were studied in an endemic region considering the use of preventative measures and mechanical control in reducing transmission of the disease. A system of ordinary differential equations was proposed, describing the dynamics and their evolution as determined by numerical simulation. Different mechanical control and prophylaxis strategies were compared to the situation without control. The basic reproduction number R? was determined R? to show that if R? > 1 there would be a risk of an epidemic and otherwise the disease would have low impact levels. The basic reproduction number helps determine the dynamics' future pattern and contrast the results so obtained with those obtained numerically. It was concluded that although prophylaxis and mechanical control alone provide effective results in controlling the disease, if both controls are combined then infection levels become significantly reduced. Around 60 % mechanical control and prevention levels are needed to provide suitable results in controlling dengue outbreaks. PMID:22030689

  9. Surveillance for Dengue and Dengue-Associated Neurologic Syndromes in the United States.

    PubMed

    Waterman, Stephen H; Margolis, Harold; Sejvar, James J

    2014-11-01

    Autochthonous dengue virus transmission has occurred in the continental United States with increased frequency during the last decade; the principal vector, Aedes aegypti, has expanded its geographic distribution in the southern United States. Dengue, a potentially fatal arboviral disease, is underreported, and US clinicians encountering patients with acute febrile illness consistent with dengue are likely to not be fully familiar with dengue diagnosis and management. Recently, investigators suggested that an outbreak of dengue likely occurred in Houston during 2003 based on retrospective laboratory testing of hospitalized cases with encephalitis and aseptic meningitis. Although certain aspects of the Houston testing results and argument for local transmission are doubtful, the report highlights the importance of prospective surveillance for dengue in Aedes-infested areas of the United States, the need for clinical training on dengue and its severe manifestations, and the need for laboratory testing in domestic patients presenting with febrile neurologic illness in these regions to include dengue. PMID:25371183

  10. Healthcare-Associated Hepatitis B and C Outbreaks Reported to the Centers for Disease Control and Prevention (CDC) in 2008-2012

    E-print Network

    Straight, Aaron

    Healthcare-Associated Hepatitis B and C Outbreaks Reported to the Centers for Disease Control and Prevention (CDC) in 2008-2012 1 The tables below summarize healthcare-associated outbreaks of hepatitis B virus (HBV) and hepatitis C virus (HCV) infection reported in the United States during 2008

  11. Lessons raised by the major 2010 dengue epidemics in the French West Indies.

    PubMed

    Larrieu, S; Cassadou, S; Rosine, J; Chappert, J L; Blateau, A; Ledrans, M; Quénel, P

    2014-03-01

    Dengue fever has been endemo-epidemic in the whole Region of America. In 2010, Guadeloupe and Martinique experienced historical epidemics, with an estimated attack rate of 10% in two islands. When considering the temporal evolution of epidemiological indicators, an unusual increase in the number of dengue cases could be detected very early. Two main factors might have facilitated the settlement of a viral transmission despite the dry season: a low immunity of the population against the circulating serotype and particular climatic conditions, notably very high temperatures which could have improved both virus and vector efficiency. This unusual situation was considered as a warning sign, and indeed led to major outbreaks in both islands a few weeks later. This event underlines that follow-up of epidemiological indicators is necessary to detect the unusual situations as soon as possible. Furthermore, development of biological and modelling tools should be promoted, as well as integrated management strategies for dengue prevention and control. PMID:24315801

  12. Mosquitoes, models, and dengue.

    PubMed

    Lifson, A R

    1996-05-01

    In the last 10 years dengue has spread markedly through Latin America and the Caribbean (Dominican Republic, Jamaica, Barbados, Mexico, Guatemala, El Salvador, Honduras, Nicaragua, Costa Rica, Panama, Ecuador, Colombia, Venezuela, and Brazil). The mosquito Aedes aegypti has taken advantage of increased urbanization and crowding to transmit the dengue virus. The mosquito infests tires, cans, and water jars near dwellings. The female mosquito practices multiple, interrupted feeding. Thus, mosquito infesting and feeding practices facilitate dengue transmission in crowded conditions. Factors contributing to the spread of dengue include numbers of infected and susceptible human hosts, strain of dengue virus, size of mosquito population, feeding habits, time from infection to ability to transmit virus for both vector and host, likelihood of virus transmission from human to mosquito to human, and temperature (which affects vector distribution, size, feeding habits, and extrinsic incubation period). Public health models may use simulation models to help them plan or evaluate the potential impact of different intervention strategies and/or of environmental changes (e.g., global warming). Other factors contributing to the dengue epidemic are international travel, urbanization, population growth, crowding, poverty, a weakened public health infrastructure, and limited support for sustained disease control programs. Molecular epidemiology by nucleic acid sequence analysis is another sophisticated technique used to study infectious diseases. It showed that dengue type 3 isolated from Panama and Nicaragua in 1994 was identical to that responsible for the major dengue hemorrhagic fever epidemics in Sri Lanka and India in the 1980s. Public health officials must remember three priorities relevant to dengue and other emerging infections: the need to strengthen surveillance efforts, dedicated and sustained involvement in prevention and control needs at the local level, and a strong public health infrastructure at the international, national, and local levels to maintain support for surveillance and control activities. PMID:8622446

  13. 75 FR 6211 - Prospective Grant of Exclusive License: Purified Inactivated Dengue Tetravalent Vaccine...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-08

    ...1970 only nine countries had experienced Dengue Hemorrhagic Fever (DHF) epidemics, a number that had increased more than four-fold...means for prevention of dengue infection and dengue hemorrhagic fever (DHF) by immunization with attenuated, immunogenic...

  14. [Prevention of an outbreak of Acinetobacter baumannii in intensive care units: study of the efficacy of different mathematical methods].

    PubMed

    Fresnadillo-Martínez, M J; García-Merino, E; García-Sánchez, E; Martín-Del Rey, A; Rodríguez-Encinas, A; Rodríguez-Sánchez, G; García-Sánchez, J E

    2015-02-01

    Introduction. Although in past decades, Acinetobacter baumanni infections have been sporadically identified in hospitals, nowadays the nosocomial infections due to this pathogen have notably increased. Its importance is due to its multidrug- resistance, morbidity and mortatility in healthcare settings. Consequently, it is important to predict the evolution of these outbreaks in order to stablish the most efficient control measures. There are several experimental studies shown that the compliance with hand and environmental hygiene and the efficient management of the healthcare work help to control the evolution of these outbreaks. The goal of this work is to formally proof these experimental results by means of the analysis of the results provided by the model. Methods. A stochastic mathematical model based on cellular automata was developed. The variables and parameters involved in it have been identified from the knowledge of the epidemiology and main characteristics of Acinetobacter infections. Results. The model provides several simulations from different initial conditions. The analysis of these results proofs in a formal way that the compliance with hand and environmental hygiene and an efficient plannification of the work of healtcare workers yield a decrease in the colonized patients. Moreover, this is the unique model proposed studying the dynamics of an outbreak of A. baumanni. Conclusions. The computational implementation of the model provides us an efficient tool in the management of outbreaks due to A. baumanni. The analysis of the simulations obtained allows us to obtain a formal proof of the behaviour of the measures for control and prevention. PMID:25690140

  15. Current perspectives on the spread of dengue in India

    PubMed Central

    Gupta, Ekta; Ballani, Neha

    2014-01-01

    Dengue fever (DF) and dengue hemorrhagic fever (DHF) are important arthropod-borne viral diseases. Each year, there are ~50 million dengue infections and ~500,000 individuals are hospitalized with DHF, mainly in Southeast Asia. Dengue in India has dramatically expanded over the last few decades, with rapidly changing epidemiology. The first major DHF outbreak in the entire nation occurred in 1996 by dengue virus serotype 2, and after a gap of almost a decade, the country faced yet another DF outbreak in the year 2003 by dengue virus serotype 3. A dramatic increase in the number and frequency of outbreaks followed, and, at present, in most of the states of India, dengue is almost endemic. At present, all the four serotypes are seen in circulation, but the predominant serotype keeps changing. Despite this trend, surveillance, reporting, and diagnosis of dengue remain largely passive in India. More active community-based epidemiological studies with intensive vector control and initiatives for dengue vaccine development should be geared up to control the spread of dengue in India. We review here the factors that may have contributed to the changing epidemiology of dengue in India. PMID:25525374

  16. Foodborne Outbreaks Surveillance Data

    MedlinePLUS

    ... and Reporting Food Safety Share Compartir Surveillance for Foodborne Disease Outbreaks Captures outbreak data from local and state ... departments on agents, foods, and settings responsible for foodborne illness Prevention from the Farm to the Table Click ...

  17. Dengue hemorrhagic fever

    MedlinePLUS

    Hemorrhagic dengue; Dengue shock syndrome; Philippine hemorrhagic fever; Thai hemorrhagic fever; Singapore hemorrhagic fever ... dengue viruses are known to cause dengue hemorrhagic fever. Dengue hemorrhagic fever occurs when a person is ...

  18. Policymakers' views on dengue fever/dengue haemorrhagic fever and the need for dengue vaccines in four southeast Asian countries.

    PubMed

    DeRoeck, Denise; Deen, Jacqueline; Clemens, John D

    2003-12-01

    A survey of policymakers and other influential professionals in four southeast Asian countries (Cambodia, Indonesia, Philippines and Vietnam) was conducted to determine policymakers' views on the public health importance of dengue fever and dengue haemorrhagic fever (DHF), the need for a vaccine and the determinants influencing its potential introduction. The survey, which involved face-to-face interviews with policymakers, health programme managers, researchers, opinion leaders and other key informants, revealed an almost uniformly high level of concern about dengue fever/DHF and a high perceived need for a dengue vaccine. Several characteristics of the disease contribute to this high sense of priority, including its geographic spread, occurrence in outbreaks, the recurrent risk of infection each dengue season, its severity and the difficulty in diagnosis and management, its urban predominance, its burden on hospitals, and its economic toll on governments and families. Research felt to be key to future decision-making regarding dengue vaccine introduction include: disease surveillance studies, in-country vaccine trials or pilot projects, and studies on the economic burden of dengue and the cost-effectiveness of dengue vaccines. The results suggest favourable conditions for public and private sector markets for dengue vaccines and the need for creative financing strategies to ensure their accessibility to poor children in dengue-endemic countries. PMID:14604579

  19. Analyzing the spatio-temporal relationship between dengue vector larval density and land-use using factor analysis and spatial ring mapping

    PubMed Central

    2012-01-01

    Background Dengue, a mosquito-borne febrile viral disease, is found in tropical and sub-tropical regions and is now extending its range to temperate regions. The spread of the dengue viruses mainly depends on vector population (Aedes aegypti and Aedes albopictus), which is influenced by changing climatic conditions and various land-use/land-cover types. Spatial display of the relationship between dengue vector density and land-cover types is required to describe a near-future viral outbreak scenario. This study is aimed at exploring how land-cover types are linked to the behavior of dengue-transmitting mosquitoes. Methods Surveys were conducted in 92 villages of Phitsanulok Province Thailand. The sampling was conducted on three separate occasions in the months of March, May and July. Dengue indices, i.e. container index (C.I.), house index (H.I.) and Breteau index (B.I.) were used to map habitats conducible to dengue vector growth. Spatial epidemiological analysis using Bivariate Pearson’s correlation was conducted to evaluate the level of interdependence between larval density and land-use types. Factor analysis using principal component analysis (PCA) with varimax rotation was performed to ascertain the variance among land-use types. Furthermore, spatial ring method was used as to visualize spatially referenced, multivariate and temporal data in single information graphic. Results Results of dengue indices showed that the settlements around gasoline stations/workshops, in the vicinity of marsh/swamp and rice paddy appeared to be favorable habitat for dengue vector propagation at highly significant and positive correlation (p = 0.001) in the month of May. Settlements around the institutional areas were highly significant and positively correlated (p = 0.01) with H.I. in the month of March. Moreover, dengue indices in the month of March showed a significant and positive correlation (p <= 0.05) with deciduous forest. The H.I. of people living around horticulture land were significantly and positively correlated (p = 0.05) during the month of May, and perennial vegetation showed a highly significant and positive correlation (p = 0.001) in the month of March with C.I. and significant and positive correlation (p <= 0.05) with B.I., respectively. Conclusions The study concluded that gasoline stations/workshops, rice paddy, marsh/swamp and deciduous forests played highly significant role in dengue vector growth. Thus, the spatio-temporal relationships of dengue vector larval density and land-use types may help to predict favorable dengue habitat, and thereby enables public healthcare managers to take precautionary measures to prevent impending dengue outbreak. PMID:23043443

  20. Co-circulation of Dengue and Chikungunya Viruses, Al Hudaydah, Yemen, 2012.

    PubMed

    Rezza, Giovanni; El-Sawaf, Gamal; Faggioni, Giovanni; Vescio, Fenicia; Al Ameri, Ranya; De Santis, Riccardo; Helaly, Ghada; Pomponi, Alice; Metwally, Dalia; Fantini, Massimo; Qadi, Hussein; Ciccozzi, Massimo; Lista, Florigio

    2014-08-01

    We investigated 400 cases of dengue-like illness in persons hospitalized during an outbreak in Al Hudaydah, Yemen, in 2012. Overall, 116 dengue and 49 chikungunya cases were diagnosed. Dengue virus type 2 was the predominant serotype. The co-circulation of these viruses indicates that mosquitoborne infections represent a public health threat in Yemen. PMID:25061762

  1. Novel Dengue Virus Type 1 from Travelers to Yap State, Micronesia

    PubMed Central

    Nukui, Yoko; Tajima, Shigeru; Kotaki, Akira; Ito, Mikako; Takasaki, Tomohiko; Koike, Kazuhiko

    2006-01-01

    Dengue virus type 1 (DENV-1), which was responsible for the dengue fever outbreak in Yap State, Micronesia, in 2004, was isolated from serum samples of 4 dengue patients in Japan. Genome sequencing demonstrated that this virus belonged to genotype IV and had a 29-nucleotide deletion in the 3´ noncoding region. PMID:16494770

  2. Pertussis Outbreak Trends

    MedlinePLUS

    ... Prevention Laboratory Public Health Professionals Fast Facts Surveillance & Reporting Outbreaks About Trends Questions & Answers Resources & Publications Prophylaxis Control Guidelines Pertussis in Other Countries Materials For Healthcare ...

  3. Dengue/dengue haemorrhagic fever

    NSDL National Science Digital Library

    0000-00-00

    A World Health Organization page devoted to the control of dengue. Many excellent informative PDF files are available from this page dealing with vector control, as well as recognition of symptoms, and treatment of dengue haemorrhagic fever. Estimated numbers of at risk people are staggering. A powerful resource for teaching the importance of vector borne diseases.

  4. Experience with the use of palivizumab together with infection control measures to prevent respiratory syncytial virus outbreaks in neonatal intensive care units.

    PubMed

    Kurz, H; Herbich, K; Janata, O; Sterniste, W; Bauer, K

    2008-11-01

    Respiratory syncytial virus (RSV) frequently causes nosocomial outbreaks in general paediatric wards and occasionally in neonatal intensive care units (NICUs). Conventional infection control measures often fail to prevent the spread of RSV, and it can cause significant morbidity especially in preterm and young infants. We report our experience in preventing an outbreak on a NICU after RSV had been detected in a premature infant. The index case was a 34-day-old premature infant who presented with clinical infection and RSV was detected in a clinical specimen. There were 11 patients in the ward at the time including the index case. The RSV-positive patient was isolated, the ward closed to admissions and infection control measures were implemented. Two patients were transferred to another hospital. Palivizumab 15 mg/kg i.m. was given to all patients and no further cases occurred. All subsequent RSV tests on nasal secretions were negative. Palivizumab combined with conventional infection control measures appeared to prevent the spread of RSV in this NICU. Strategies for the prevention of RSV outbreaks on NICUs all recommend the reinforcement of routine infection control measures. Recommendations concerning the use of palivizumab range from monthly prophylaxis to all infants at risk, to prophylaxis of selected cases only. Currently there are no guidelines for the use of palivizumab in NICUs or for the control of RSV outbreaks. PMID:18799241

  5. Dengue Fever

    MedlinePLUS

    ... email updates Order publications Featured Research One small RNA regulates mosquito development, growth, and reproduction. Read more ... the 20th century, many tropical regions of the world saw an increase in dengue cases. Epidemics also ...

  6. Dengue fever

    MedlinePLUS

    ... that is spread by mosquitoes. See also: Dengue hemorrhagic fever ... by the bite of mosquitoes, most commonly the mosquito Aedes aegypti ... hemorrhagic fever , which is a separate disease that is caused ...

  7. Detection of dengue virus 4 from central India

    PubMed Central

    Barde, P.V.; Godbole, S.; Bharti, P.K.; Chand, Gyan; Agarwal, M.; Singh, Neeru

    2012-01-01

    Background & objectives: Dengue is an important arboviral disease. All four dengue virus serotypes are reported to be circulating in India. It is also known that different serotypes, genotypes and clades of genotype determine outbreak severity. Dengue affected children are known to have serious disease outcome. We carried out this study to give reliable diagnosis of dengue infection in children and to detect circulating serotype in central India. Methods: Samples collected from paediatric patients suspected to have dengue fever were subjected to IgM and IgG ELISA to determine dengue virus infection. Samples collected within 0-5 days of onset of illness and positive by IgM ELISA were tested by nested reverse transcription polymerase chain reaction (nRT-PCR). The PCR products were sequenced and analyzed. Results: Of the 89 samples tested, 18 and 7 were positive for dengue IgM and IgG, respectively. Dengue activity was observed in both Jabalpur city and adjoining rural settings. One sample found positive by nRT-PCR was further sequenced to confirm dengue virus 4 as aetiological agent. Interpretation & conclusions: Our findings demonstrated dengue virus infection in children and adolescent in central India. Because of continuous changing epidemiology, it is important to monitor dengue virus activity at both serological and molecular level in this part of the country for better patient care and management. PMID:23041745

  8. Strategies for preventing invasive plant outbreaks after prescribed fire in ponderosa pine forest

    USGS Publications Warehouse

    Symstad, Amy J.; Newton, Wesley E.; Swanson, Daniel J.

    2014-01-01

    Land managers use prescribed fire to return a vital process to fire-adapted ecosystems, restore forest structure from a state altered by long-term fire suppression, and reduce wildfire intensity. However, fire often produces favorable conditions for invasive plant species, particularly if it is intense enough to reveal bare mineral soil and open previously closed canopies. Understanding the environmental or fire characteristics that explain post-fire invasive plant abundance would aid managers in efficiently finding and quickly responding to fire-caused infestations. To that end, we used an information-theoretic model-selection approach to assess the relative importance of abiotic environmental characteristics (topoedaphic position, distance from roads), pre-and post-fire biotic environmental characteristics (forest structure, understory vegetation, fuel load), and prescribed fire severity (measured in four different ways) in explaining invasive plant cover in ponderosa pine forest in South Dakota’s Black Hills. Environmental characteristics (distance from roads and post-fire forest structure) alone provided the most explanation of variation (26%) in post-fire cover of Verbascum thapsus (common mullein), but a combination of surface fire severity and environmental characteristics (pre-fire forest structure and distance from roads) explained 36–39% of the variation in post-fire cover of Cirsium arvense (Canada thistle) and all invasives together. For four species and all invasives together, their pre-fire cover explained more variation (26–82%) in post-fire cover than environmental and fire characteristics did, suggesting one strategy for reducing post-fire invasive outbreaks may be to find and control invasives before the fire. Finding them may be difficult, however, since pre-fire environmental characteristics explained only 20% of variation in pre-fire total invasive cover, and less for individual species. Thus, moderating fire intensity or targeting areas of high severity for post-fire invasive control may be the most efficient means for reducing the chances of post-fire invasive plant outbreaks when conducting prescribed fires in this region.

  9. [Dengue fever in the Reunion Island and in South Western islands of the Indian Ocean].

    PubMed

    D'Ortenzio, E; Balleydier, E; Baville, M; Filleul, L; Renault, P

    2011-09-01

    South Western islands of the Indian Ocean are permanently threatened by dengue fever outbreaks. On the Reunion Island, two dengue outbreaks were biologically documented (1977-1978 and 2004). And since July 2004 there has been an inter-epidemic period for the island with sporadic cases and clusters. Between January 1, 2007 and October 5, 2009, the epidemiologic surveillance system detected five confirmed autochthonous cases, five confirmed imported cases (South-East Asia), and 71 probable cases. All the five autochthonous confirmed cases occurred in Saint-Louis during two consecutive clusters. In other South Western islands of the Indian Ocean, several dengue fever outbreaks have been reported. Importation of dengue virus from South-East Asia is a major risk for a new outbreak on the island. The introduction of a new serotype could lead to the emergence of new and severe clinical forms, including dengue hemorrhagic fever. PMID:21295427

  10. Confusion, knock-down and kill of Aedes aegypti using metofluthrin in domestic settings: a powerful tool to prevent dengue transmission?

    PubMed Central

    2013-01-01

    Background Dengue control methods are reliant upon control of the vector, primarily Aedes aegypti. Current adulticiding methods in North Queensland include treating premises with residual synthetic pyrethroid insecticides (interior residual spraying; IRS), a laborious, intrusive task. The vapor active synthetic pyrethroid metofluthrin might offer an efficient alternative as some studies indicate that it prevents biting and has strong knockdown effects. However, its expellant and/or irritant effects, longevity, residual activity and the speed with which biting behavior is disrupted have not yet been characterized. Methods We exposed cohorts of Cairns colony (F2-4) Ae. aegypti to rooms (17–24 m3) treated with 5% and 10% AI metofluthrin emanators. Using free-flying and caged populations we measured biting (human landing rate), expulsion through unscreened windows, knockdown and death over periods ranging between a few minutes and 24 hrs. Observations of the behavior of single female Ae. aegypti exposed to metofluthrin were also made. Results Female Ae. aegypti exposed to 5% or 10% metofluthrin formulations were almost entirely inhibited from biting. This was the result of rapid knockdown and mortality (80-90% in less than one hour) and to the behavioral impacts of exposure that, within minutes, caused female Ae. aegypti to become disoriented, stop landing on hosts, and seek resting sites. Exposed mosquitoes did not exhibit any increased propensity to exit treated rooms and the 10% AI resin remained fully active for at least 20 days. Conclusion The new, high-dose, resin formulations of metofluthrin act quickly to prevent biting and to knockdown and kill free-flying female Ae. aegypti in our experimental rooms. There was no evidence that metofluthrin induced escape from treated areas. Resin-based metofluthrin emanators show great potential as a replacement for labor intensive IRS for dengue vector control. PMID:24025232

  11. Dengue Occurrence in the Population (Epidemiology)

    MedlinePLUS

    ... occurs every year, usually during a season when Aedes mosquito populations are high, often when rainfall is optimal ... United States, 1999 and 2000 ) Because contact between Aedes and people is ... Hemorrhagic Fever - U.S.- Mexico Border, 2005 ) A small dengue outbreak ...

  12. [Hepatitis B outbreak in a day care center affected several families. It could have been prevented by vaccination of all children].

    PubMed

    Broholm, K A; Sjödin, L; Backlund, I; Johansson, B; Norder, H; Magnius, L

    2001-05-01

    An outbreak of hepatitis B originating in a family day nursery affected several children with Somali background. The transmission chain was confirmed by sequence analysis of the S gene. In Africa hepatitis B is often spread horizontally among children of pre-school age, a pattern of transmission that was retained in this outbreak. To limit the outbreak 126 children in the nursery and 50 members of staff had to be vaccinated. The total cost for this intervention was estimated to about 300,000 SEK. Considering the great number of immigrants in Sweden from areas highly endemic for hepatitis B the inclusion of vaccination in the general child immunisation program seems to be the most cost effective measure for long term prevention not only of hepatitis B transmission among children but also of venereal spread in early adulthood. PMID:11402989

  13. Dengue vaccines: challenges, development, current status and prospects.

    PubMed

    Ghosh, A; Dar, L

    2015-01-01

    Infection with dengue virus (DENV) is the most rapidly spreading mosquito-borne viral disease in the world. The clinical spectrum of dengue, caused by any of the four serotypes of DENV, ranges from mild self-limiting dengue fever to severe dengue, in the form dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS). Increased rates of hospitalization due to severe dengue, during outbreaks, result in massive economic losses and strained health services. In the absence of specific antiviral therapy, control of transmission of DENV by vector management is the sole method available for decreasing dengue-associated morbidity. Since vector control strategies alone have not been able to satisfactorily achieve reduction in viral transmission, the implementation of a safe, efficacious and cost-effective dengue vaccine as a supplementary measure is a high public health priority. However, the unique and complex immunopathology of dengue has complicated vaccine development. Dengue vaccines have also been challenged by critical issues like lack of animal models for the disease and absence of suitable markers of protective immunity. Although no licensed dengue vaccine is yet available, several vaccine candidates are under phases of development, including live attenuated virus vaccines, live chimeric virus vaccines, inactivated virus vaccines, subunit vaccines, DNA vaccines and viral-vectored vaccines. Although some vaccine candidates have progressed from animal trials to phase II and III in humans, a number of issues regarding implementation of dengue vaccine in countries like India still need to be addressed. Despite the current limitations, collaborative effects of regulatory bodies like World Health Organization with vaccine manufacturers and policy makers, to facilitate vaccine development and standardize field trials can make a safe and efficacious dengue vaccine a reality in near future. PMID:25559995

  14. Travelers' Health: Dengue Fever

    MedlinePLUS

    ... with any 1 of 4 related positive-strand RNA viruses of the genus Flavivirus , dengue viruses (DENV) ... Box 3-01 for information regarding the new World Health Organization (WHO) guidelines for classifying dengue. Dengue ...

  15. Direct costs associated with a nosocomial outbreak of Salmonella infection: An ounce of prevention is worth a pound of cure

    Microsoft Academic Search

    N. M. Spearing; A. Jensen; B. J. McCall; A. S. Neill; J. G. McCormack

    2000-01-01

    Background: Nosocomial outbreaks of Salmonella infections in Australia are an infrequent but significant source of morbidity and mortality. Such an outbreak results in direct, measurable expenses for acute care management, as well as numerous indirect (and less quantifiable) costs to those affected, the hospital, and the wider community. This article describes the significant direct costs incurred as a result of

  16. Evaluation of ASSURE® Dengue IgA Rapid Test using dengue-positive and dengue-negative samples.

    PubMed

    Ahmed, Firoz; Mursalin, Huzzatul; Alam, Meer Taifur; Amin, Ruhul; Sekaran, Shamala Devi; Wang, Seok Mui; Tan, Yun Ying; Sil, Bijon Kumar; Hossain, M Anowar

    2010-12-01

    ASSURE® Dengue IgA Rapid Test, an immunochromatographic anti-Dengue IgA Rapid Test based on reverse flow technology, was evaluated using archived sera. The sera were obtained during hospital admission and discharge of 204 patients during 2000 to 2001 dengue outbreak in Bangladesh and 220 negative sera collected in 2009. Based on characterization by reference ELISA (nonstructural protein 1 [NS1] Ag ELISA, immunoglobulin M [IgM]-Cap ELISA, and immunoglobulin G [IgG]-Cap ELISA), 179 (87.7%) patients were positive for dengue infection, and the remaining 245 patients had nondengue febrile illness. The performance of Dengue IgA Rapid Test was compared to reference ELISA. Of 179 dengue-positive sera, 79 (44.1%) were positive by NS1 Ag ELISA, 174 (97.2%) were positive by IgM-Cap ELISA, and 142 (79.3%) were positive by IgG-Cap ELISA. Among 142 IgG-positive cases, 121 (85.2%) patients had shown high level of IgG (PanBio units ? 22, equivalent to hemagglutination inhibition (HI) titer ? 2560) during hospital admission, indicating secondary infections. Dengue IgA Rapid Test demonstrated 99.4% (178 of 179) sensitivity in diagnosing dengue infection with the ability to detect 100% primary (58 of 58) and 99.2% (120 of 121) secondary infections, and the specificity was found 99.2% (2 of 245). The capability of Dengue IgA Rapid Test in detecting dengue infection in terms of day of illness was comparable to reverse transcriptase polymerase chain reaction and was found better than in-house IgM ELISA. Compared with in-house IgM ELISA, Dengue IgA Rapid Test also detected similar number of dengue virus (DENV) 1, DENV 2, and more DENV 3 and DENV 4 cases. The overall performance thus suggested its usefulness as one of the dengue early diagnostic tools where diagnostic facility is limited. PMID:20884152

  17. Climate-Based Models for Understanding and Forecasting Dengue Epidemics

    PubMed Central

    Descloux, Elodie; Mangeas, Morgan; Menkes, Christophe Eugène; Lengaigne, Matthieu; Leroy, Anne; Tehei, Temaui; Guillaumot, Laurent; Teurlai, Magali; Gourinat, Ann-Claire; Benzler, Justus; Pfannstiel, Anne; Grangeon, Jean-Paul; Degallier, Nicolas; De Lamballerie, Xavier

    2012-01-01

    Background Dengue dynamics are driven by complex interactions between human-hosts, mosquito-vectors and viruses that are influenced by environmental and climatic factors. The objectives of this study were to analyze and model the relationships between climate, Aedes aegypti vectors and dengue outbreaks in Noumea (New Caledonia), and to provide an early warning system. Methodology/Principal Findings Epidemiological and meteorological data were analyzed from 1971 to 2010 in Noumea. Entomological surveillance indices were available from March 2000 to December 2009. During epidemic years, the distribution of dengue cases was highly seasonal. The epidemic peak (March–April) lagged the warmest temperature by 1–2 months and was in phase with maximum precipitations, relative humidity and entomological indices. Significant inter-annual correlations were observed between the risk of outbreak and summertime temperature, precipitations or relative humidity but not ENSO. Climate-based multivariate non-linear models were developed to estimate the yearly risk of dengue outbreak in Noumea. The best explicative meteorological variables were the number of days with maximal temperature exceeding 32°C during January–February–March and the number of days with maximal relative humidity exceeding 95% during January. The best predictive variables were the maximal temperature in December and maximal relative humidity during October–November–December of the previous year. For a probability of dengue outbreak above 65% in leave-one-out cross validation, the explicative model predicted 94% of the epidemic years and 79% of the non epidemic years, and the predictive model 79% and 65%, respectively. Conclusions/Significance The epidemic dynamics of dengue in Noumea were essentially driven by climate during the last forty years. Specific conditions based on maximal temperature and relative humidity thresholds were determinant in outbreaks occurrence. Their persistence was also crucial. An operational model that will enable health authorities to anticipate the outbreak risk was successfully developed. Similar models may be developed to improve dengue management in other countries. PMID:22348154

  18. Role of cognitive parameters in dengue hemorrhagic fever and dengue shock syndrome

    PubMed Central

    2013-01-01

    Dengue is becoming recognized as one of the most important vector-borne human diseases. It is predominant in tropical and subtropical zones but its geographical distribution is progressively expanding, making it an escalating global health problem of today. Dengue presents with spectrum of clinical manifestations, ranging from asymptomatic, undifferentiated mild fever, dengue fever (DF), to dengue hemorrhagic fever (DHF) with or without shock (DSS), a life-threatening illness characterized by plasma leakage due to increased vascular permeability. Currently, there are no antiviral modalities or vaccines available to treat and prevent dengue. Supportive care with close monitoring is the standard clinical practice. The mechanisms leading to DHF/DSS remains poorly understood. Multiple factors have been attributed to the pathological mechanism, but only a couple of these hypotheses are popular in scientific circles. The current discussion focuses on underappreciated factors, temperature, natural IgM, and endotoxin, which may be critical components playing roles in dengue pathogenesis. PMID:24305068

  19. Epidemiology of dengue: past, present and future prospects

    PubMed Central

    Murray, Natasha Evelyn Anne; Quam, Mikkel B; Wilder-Smith, Annelies

    2013-01-01

    Dengue is currently regarded globally as the most important mosquito-borne viral disease. A history of symptoms compatible with dengue can be traced back to the Chin Dynasty of 265–420 AD. The virus and its vectors have now become widely distributed throughout tropical and subtropical regions of the world, particularly over the last half-century. Significant geographic expansion has been coupled with rapid increases in incident cases, epidemics, and hyperendemicity, leading to the more severe forms of dengue. Transmission of dengue is now present in every World Health Organization (WHO) region of the world and more than 125 countries are known to be dengue endemic. The true impact of dengue globally is difficult to ascertain due to factors such as inadequate disease surveillance, misdiagnosis, and low levels of reporting. Currently available data likely grossly underestimates the social, economic, and disease burden. Estimates of the global incidence of dengue infections per year have ranged between 50 million and 200 million; however, recent estimates using cartographic approaches suggest this number is closer to almost 400 million. The expansion of dengue is expected to increase due to factors such as the modern dynamics of climate change, globalization, travel, trade, socioeconomics, settlement and also viral evolution. No vaccine or specific antiviral therapy currently exists to address the growing threat of dengue. Prompt case detection and appropriate clinical management can reduce the mortality from severe dengue. Effective vector control is the mainstay of dengue prevention and control. Surveillance and improved reporting of dengue cases is also essential to gauge the true global situation as indicated in the objectives of the WHO Global Strategy for Dengue Prevention and Control, 2012–2020. More accurate data will inform the prioritization of research, health policy, and financial resources toward reducing this poorly controlled disease. The objective of this paper is to review historical and current epidemiology of dengue worldwide and, additionally, reflect on some potential reasons for expansion of dengue into the future. PMID:23990732

  20. Re-Emergence of Dengue Virus Type 3 in Canton, China, 2009–2010, Associated with Multiple Introductions through Different Geographical Routes

    PubMed Central

    Di, Biao; Bai, Zhijun; He, Peng; Jing, Qinlong; Zheng, Xueli

    2013-01-01

    Background Endemic dengue virus type 3 (DENV-3) infections have not been reported in Canton, China, since 1980. In March 2009, DENV-3 was isolated for the second time, occurring about 30 years after the previous circulation. In August, 3 other cases emerged. One much larger outbreak occurred again in 2010. To address the origin and particularly to determine whether the outbreaks were caused by the same viral genotype, we investigated the epidemiological and molecular characteristics of the introduction, spread and genetic microevolution of DENV-3 involved. Methodology/Principal Findings Three imported cases (index-1,2,3) separately traveled back from Vietnam, India and Tanzania, resulted in 1, 3 and 60 secondary autochthonous cases, respectively. In autochthonous cases, 64.6% positive in IgM anti-DENV and 18.6% in IgG from a total of 48 submitted serum samples, accompanied by 7 DENV-3 isolates. With 99.8%, 99.7%, and 100% envelope gene nucleotidic identity, 09/GZ/1081 from index-1 and endemic strain (09/GZ/1483) belonged to genotype V; 09/GZ/10616 from index-2 and endemic strains (09/GZ/11144 and 09/GZ/11194) belonged to genotype III Clade-A; and 10/GZ/4898 from index-3 and all four 2010 endemic DENV-3 strains belonged to genotype III Clade-B, respectively. Conclusions/Significance Both epidemiological and phylogenetic analyses showed that the 2010 outbreak of dengue was not a reemergence of the 2009 strain. Introductions of different genotypes following more than one route were important contributory factors for the 2009–2010 dengue epidemics/outbreaks in Canton. These findings underscore the importance of early detection and case management of imported case in preventing large-scale dengue epidemics among indigenous peoples of Canton. PMID:23405138

  1. Community beliefs and practices about dengue in Puerto Rico

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In spite of long-term endemicity and repeated government and private efforts, effective, sustained community participation for dengue prevention is still a challenge in Puerto Rico. This study explored differences found in interviews conducted in 2001 in attitudes toward dengue and its prevention by...

  2. Importance of Internet Surveillance in Public Health Emergency Control and Prevention: Evidence From a Digital Epidemiologic Study During Avian Influenza A H7N9 Outbreaks

    PubMed Central

    Zhu, Honghong; Jiang, Tao; Wang, Xinyi; Chen, Lei; Jiang, Zhenggang; Zheng, Dawei

    2014-01-01

    Background Outbreaks of human infection with a new avian influenza A H7N9 virus occurred in China in the spring of 2013. Control and prevention of a new human infectious disease outbreak can be strongly affected by public reaction and social impact through the Internet and social media. Objective This study aimed to investigate the potential roles of Internet surveillance in control and prevention of the human H7N9 outbreaks. Methods Official data for the human H7N9 outbreaks were collected via the China National Health and Family Planning Committee website from March 31 to April 24, 2013. We obtained daily posted and forwarded number of blogs for the keyword “H7N9” from Sina microblog website and a daily Baidu Attention Index (BAI) from Baidu website, which reflected public attention to the outbreak. Rumors identified and confirmed by the authorities were collected from Baidu search engine. Results Both daily posted and forwarded number and BAI for keyword H7N9 increased quickly during the first 3 days of the outbreaks and remained at a high level for 5 days. The total daily posted and forwarded number for H7N9 on Sina microblog peaked at 850,000 on April 3, from zero blogs before March 31, increasing to 97,726 on April 1 and to 370,607 on April 2, and remaining above 500,000 from April 5-8 before declining to 208,524 on April 12. The total daily BAI showed a similar pattern of change to the total daily posted and forwarded number over time from March 31 to April 12. When the outbreak locations spread, especially into other areas of the same province/city and the capital, Beijing, daily posted and forwarded number and BAI increased again to a peak at 368,500 and 116,911, respectively. The median daily BAI during the studied 25 days was significantly higher among the 7 provinces/cities with reported human H7N9 cases than the 2 provinces without any cases (P<.001). So were the median daily posted and forwarded number and daily BAI in each province/city except Anhui province. We retrieved a total of 32 confirmed rumors spread across 19 provinces/cities in China. In all, 84% (27/32) of rumors were disseminated and transmitted by social media. Conclusions The first 3 days of an epidemic is a critical period for the authorities to take appropriate action through Internet surveillance to prevent and control the epidemic, including preparation of personnel, technology, and other resources; information release; collection of public opinion and reaction; and clarification, prevention, and control of rumors. Internet surveillance can be used as an efficient and economical tool to prevent and control public health emergencies, such as H7N9 outbreaks. PMID:24440770

  3. Dengue/Severe Dengue Frequently Asked Questions

    MedlinePLUS

    ... ??????? Español RSS Feed Youtube Twitter Facebook Google + iTunes Play Store Dengue control Menu Dengue Control strategies ... Twitter WHO Facebook page WHO Google+ page WHO iTunes WHO Play Store © WHO 2015 Back to top ...

  4. Wolbachia versus dengue

    PubMed Central

    Bull, James J.; Turelli, Michael

    2013-01-01

    A novel form of biological control is being applied to the dengue virus. The agent is the maternally transmitted bacterium Wolbachia, naturally absent from the main dengue vector, the mosquito Aedes aegypti. Three Wolbachia-based control strategies have been proposed. One is suppression of mosquito populations by large-scale releases of males incompatible with native females; this intervention requires ongoing releases. The other interventions transform wild mosquito populations with Wolbachia that spread via the frequency-dependent fitness advantage of Wolbachia-infected females; those interventions potentially require just a single, local release for area-wide disease control. One of these latter strategies uses Wolbachia that shortens mosquito life, indirectly preventing viral maturation/transmission. The other strategy uses Wolbachia that block viral transmission. All interventions can be undermined by viral, bacterial or mosquito evolution; viral virulence in humans may also evolve. We examine existing theory, experiments and comparative evidence to motivate predictions about evolutionary outcomes. (i) The life-shortening strategy seems the most likely to be thwarted by evolution. (ii) Mosquito suppression has a reasonable chance of working locally, at least in the short term, but long-term success over large areas is challenging. (iii) Dengue blocking faces strong selection for viral resistance but may well persist indefinitely at some level. Virulence evolution is not mathematically predictable, but comparative data provide no precedent for Wolbachia increasing dengue virulence. On balance, our analysis suggests that the considerable possible benefits of these technologies outweigh the known negatives, but the actual risk is largely unknown. PMID:24481199

  5. Neutralizing Dengue Antibody in Pregnant Thai Women and Cord Blood

    PubMed Central

    Khamim, Kriangsak; Hattasingh, Weerawan; Nisalak, Ananda; Kaewkungwal, Jaranit; Fernandez, Stefan; Thaisomboonsuk, Butsaya; Pengsaa, Krisana; Thisyakorn, Usa

    2015-01-01

    Background The WHO ‘Global Strategy for Dengue Prevention and Control, 2012–2020’ addresses the growing need for the treatment of dengue, and targets a 25% reduction in morbidity and 50% in mortality (using 2010 estimates as baseline). Achieving these goals requires future dengue prevention strategies that will employ both potential vaccines and sustainable vector-control measures. Maternally transferred dengue antibody is an important factor in determining the optimal age for dengue vaccination. Objectives To estimate the seroprevalence of dengue antibodies among mothers living in an area of high endemicity – Ban Pong, Ratchaburi Province – and to assess maternal dengue antibodies transferred to cord blood. Materials & Methods A cross-sectional study was conducted with 141 pregnant women who delivered at Ban Pong Hospital, Ratchaburi, Thailand. Maternal-cord paired sera were tested for dengue neutralizing (NT) antibody by PRNT50 assay. A ratio of ? 1:10 NT titer to dengue serotype was considered seropositive. Results Most mothers (137/141, 97.2%) had NT antibodies to at least one dengue serotype in their sera. At birth, the proportion of cord sera with NT antibodies to DEN-1, DEN-2, DEN-3, and DEN-4, were high and similar to the sera of their mothers, at 93.6%, 97.2%, 97.9%, and 92.2%, respectively. The dengue geometric mean titers (GMT) in cord blood were significantly higher than the maternal antibodies (p<0.001): highest in DEN-2, followed by DEN-3, and then DEN-1. The GMT of DEN-4 was the lowest among all four serotypes. Conclusions Dengue infection is highly prevalent among pregnant women in this dengue-endemic area. Most of the cord blood had transferred dengue antibodies, which may have an impact on the disease burden in this population. PMID:25658481

  6. Eventual Role of Asymptomatic Cases of Dengue for the Introduction and Spread of Dengue Viruses in Non-Endemic Regions

    PubMed Central

    Chastel, Claude

    2012-01-01

    In dengue virus infections the asymptomatic cases are much more frequent than the symptomatic ones, but their true role in the introduction and subsequent spread of dengue viruses in non-endemic regions remains to de clarified. We analyzed data from English and French literatures to assess if viremia in asymptomatic dengue infections might be sufficient to represent a true risk. During outbreaks of dengue a large number of individuals are infected and since viremia levels in symptomatic patients are known to vary by many orders of magnitude, it is reasonable to augur that a proportion of asymptomatic cases might reach levels of viremia sufficient to infect competent mosquitoes. In addition, a number of new ways of contamination in man by dengue viruses were recently described such as blood transfusion, bone marrow transplantation, and nosocomial infections that may be worth considering. PMID:22479252

  7. Knowledge, attitudes and practices regarding dengue infection in Westmoreland, Jamaica

    PubMed Central

    Shuaib, Faisal; Todd, Dana; Campbell-Stennett, Dianne; Ehiri, John; Jolly, Pauline E.

    2010-01-01

    Background Dengue virus infection causes significant morbidity and mortality in most tropical and sub-tropical countries of the world. Dengue fever is endemic in Jamaica and continues to be a public health concern. There is a paucity of information on knowledge, attitudes, and practices (KAP) of Jamaicans regarding dengue infection. Objective To describe dengue related knowledge, attitudes and practices (KAP) of residents of Westmoreland, Jamaica. Methods A cross-sectional questionnaire survey of 192 parents attending child health clinics in the Parish of Westmoreland was conducted. Results More than half of the parents (54%) had good knowledge about signs, symptoms, and modes of transmission of dengue. Approximately 47% considered dengue to be a serious but preventable disease to which they are vulnerable. Nevertheless, a majority (77%) did not use effective dengue preventive methods such as screening of homes and 51% did not use bed nets. Educational attainment (OR, 2.98; CI, 1.23–7.23) was positively associated with knowledge of dengue. There was no correlation between knowledge about dengue and preventive practices (p=0.34). Radio and TV were the predominant sources of information about dengue fever. Conclusion Our findings suggest that the good knowledge about dengue fever among residents of Westmoreland did not translate to adoption of preventive measures. Health program planners and practitioners need to identify and facilitate removal of barriers to behavior change related to control of dengue fever among the population. Future campaigns should focus on educating and encouraging individuals and families to adopt such simple, inexpensive preventive actions, such as, use of insecticide treated bed nets and screening of homes. PMID:21132094

  8. Quantifying the Emergence of Dengue in Hanoi, Vietnam: 1998–2009

    PubMed Central

    Cuong, Hoang Quoc; Hien, Nguyen Tran; Duong, Tran Nhu; Phong, Tran Vu; Cam, Nguyen Nhat; Farrar, Jeremy; Nam, Vu Sinh; Thai, Khoa T. D.; Horby, Peter

    2011-01-01

    Background An estimated 2.4 billion people live in areas at risk of dengue transmission, therefore the factors determining the establishment of endemic dengue in areas where transmission suitability is marginal is of considerable importance. Hanoi, Vietnam is such an area, and following a large dengue outbreak in 2009, we set out to determine if dengue is emerging in Hanoi. Methods and Principal Findings We undertook a temporal and spatial analysis of 25,983 dengue cases notified in Hanoi between 1998 and 2009. Age standardized incidence rates, standardized age of infection, and Standardized Morbidity Ratios (SMR) were calculated. A quasi-Poisson regression model was used to determine if dengue incidence was increasing over time. Wavelet analysis was used to explore the periodicity of dengue transmission and the association with climate variables. After excluding the two major outbreak years of 1998 and 2009 and correcting for changes in population age structure, we identified a significant annual increase in the incidence of dengue cases over the period 1999–2008 (incidence rate ratio ?=?1.38, 95% confidence interval ?=?1.20–1.58, p value ?=?0.002). The age of notified dengue cases in Hanoi is high, with a median age of 23 years (mean 26.3 years). After adjusting for changes in population age structure, there was no statistically significant change in the median or mean age of dengue cases over the period studied. Districts in the central, highly urban, area of Hanoi have the highest incidence of dengue (SMR>3). Conclusions Hanoi is a low dengue transmission setting where dengue incidence has been increasing year on year since 1999. This trend needs to be confirmed with serological surveys, followed by studies to determine the underlying drivers of this emergence. Such studies can provide insights into the biological, demographic, and environmental changes associated with vulnerability to the establishment of endemic dengue. PMID:21980544

  9. A brief review on dengue molecular virology, diagnosis, treatment and prevalence in Pakistan.

    PubMed

    Idrees, Sobia; Ashfaq, Usman A

    2012-01-01

    Dengue virus infection is a serious health problem infecting 2.5 billion people worldwide. Dengue is now endemic in more than 100 countries, including Pakistan. Each year hundreds of people get infected with dengue in Pakistan. Currently, there is no vaccine available for the prevention of Dengue virus infection due to four viral serotypes. Dengue infection can cause death of patients in its most severity, meanwhile many antiviral compounds are being tested against dengue virus infection to eradicate this disease but still there is a need to develop an efficient, low-cost and safe vaccine that can target all the four serotypes of dengue virus. This review summarizes dengue molecular virology, important drug targets, prevalence in Pakistan, diagnosis, treatment and medicinal plant inhibitors against dengue. PMID:22929369

  10. A brief review on dengue molecular virology, diagnosis, treatment and prevalence in Pakistan

    PubMed Central

    2012-01-01

    Dengue virus infection is a serious health problem infecting 2.5 billion people worldwide. Dengue is now endemic in more than 100 countries, including Pakistan. Each year hundreds of people get infected with dengue in Pakistan. Currently, there is no vaccine available for the prevention of Dengue virus infection due to four viral serotypes. Dengue infection can cause death of patients in its most severity, meanwhile many antiviral compounds are being tested against dengue virus infection to eradicate this disease but still there is a need to develop an efficient, low-cost and safe vaccine that can target all the four serotypes of dengue virus. This review summarizes dengue molecular virology, important drug targets, prevalence in Pakistan, diagnosis, treatment and medicinal plant inhibitors against dengue. PMID:22929369

  11. Spatio-Temporal Diffusion Pattern and Hotspot Detection of Dengue in Chachoengsao Province, Thailand

    PubMed Central

    Jeefoo, Phaisarn; Tripathi, Nitin Kumar; Souris, Marc

    2011-01-01

    In recent years, dengue has become a major international public health concern. In Thailand it is also an important concern as several dengue outbreaks were reported in last decade. This paper presents a GIS approach to analyze the spatial and temporal dynamics of dengue epidemics. The major objective of this study was to examine spatial diffusion patterns and hotspot identification for reported dengue cases. Geospatial diffusion pattern of the 2007 dengue outbreak was investigated. Map of daily cases was generated for the 153 days of the outbreak. Epidemiological data from Chachoengsao province, Thailand (reported dengue cases for the years 1999–2007) was used for this study. To analyze the dynamic space-time pattern of dengue outbreaks, all cases were positioned in space at a village level. After a general statistical analysis (by gender and age group), data was subsequently analyzed for temporal patterns and correlation with climatic data (especially rainfall), spatial patterns and cluster analysis, and spatio-temporal patterns of hotspots during epidemics. The results revealed spatial diffusion patterns during the years 1999–2007 representing spatially clustered patterns with significant differences by village. Villages on the urban fringe reported higher incidences. The space and time of the cases showed outbreak movement and spread patterns that could be related to entomologic and epidemiologic factors. The hotspots showed the spatial trend of dengue diffusion. This study presents useful information related to the dengue outbreak patterns in space and time and may help public health departments to plan strategies to control the spread of disease. The methodology is general for space-time analysis and can be applied for other infectious diseases as well. PMID:21318014

  12. A review of the vector management methods to prevent and control outbreaks of West Nile virus infection and the challenge for Europe

    PubMed Central

    2014-01-01

    West Nile virus infection is a growing concern in Europe. Vector management is often the primary option to prevent and control outbreaks of the disease. Its implementation is, however, complex and needs to be supported by integrated multidisciplinary surveillance systems and to be organized within the framework of predefined response plans. The impact of the vector control measures depends on multiple factors and the identification of the best combination of vector control methods is therefore not always straightforward. Therefore, this contribution aims at critically reviewing the existing vector control methods to prevent and control outbreaks of West Nile virus infection and to present the challenges for Europe. Most West Nile virus vector control experiences have been recently developed in the US, where ecological conditions are different from the EU and vector control is organized under a different regulatory frame. The extrapolation of information produced in North America to Europe might be limited because of the seemingly different epidemiology in the European region. Therefore, there is an urgent need to analyse the European experiences of the prevention and control of outbreaks of West Nile virus infection and to perform robust cost-benefit analysis that can guide the implementation of the appropriate control measures. Furthermore, to be effective, vector control programs require a strong organisational backbone relying on a previously defined plan, skilled technicians and operators, appropriate equipment, and sufficient financial resources. A decision making guide scheme is proposed which may assist in the process of implementation of vector control measures tailored on specific areas and considering the available information and possible scenarios. PMID:25015004

  13. Dengue in China: a clinical review.

    PubMed Central

    Qiu, F. X.; Gubler, D. J.; Liu, J. C.; Chen, Q. Q.

    1993-01-01

    Three etiologically proven outbreaks of dengue fever and one etiologically confirmed epidemic of dengue haemorrhagic fever have occurred in south China since 1978. The first of these, an epidemic of dengue due to virus type 4 took place in Shiwan town, Foshan city, Guangdong Province, in 1978; the epidemic began in May and ended in November. The clinical manifestations of 583 hospitalized patients were observed from August to October. The majority (81.3%) of patients were aged 21-50 years (male:female = 1.2:1). The course of illness was about 1 week in most cases; three patients (0.5%) died. A local outbreak of dengue due to virus type 1 occurred in Shiqi town, Zhongshan County, Guangdong Province, from September to November 1979. The majority of patients were older children and adolescents. There was no marked difference between males and females in terms of the course of the illness, and there were no complications or deaths. A large epidemic of dengue due to virus type 3 occurred on Hainan Island in 1980. The clinical manifestations of 510 hospitalized patients (mostly adolescents and adults) were observed from April to September. Some patients developed rare complications, such as loss of hair, acute intravascular haemolysis, and multiple peripheral paralysis; there were four deaths (0.78%). The first known epidemic of dengue haemorrhagic fever in China occurred among 10-29-year-olds on Hainan Island in 1985 and 1986. There were no essential differences between males and females. Some cases had rare complications such as acute intravascular haemolysis, while others had diffuse intravascular coagulation and altered mental status; 10 patients (6.5%) died. PMID:8324854

  14. Infection prevention and control interventions in the first outbreak of methicillin-resistant Staphylococcus aureus infections in an equine hospital in Sweden

    PubMed Central

    2012-01-01

    Background The first outbreak of methicillin-resistant Staphylococcus aureus (MRSA) infection in horses in Sweden occurred in 2008 at the University Animal Hospital and highlighted the need for improved infection prevention and control. The present study describes interventions and infection prevention control in an equine hospital setting July 2008 - April 2010. Method This descriptive study of interventions is based on examination of policy documents, medical records, notes from meetings and cost estimates. MRSA cases were identified through clinical sampling and telephone enquiries about horses post-surgery. Prospective sampling in the hospital environment with culture for MRSA and genotyping of isolates by spa-typing and pulsed-field gel electrophoresis (PFGE) were performed. Results Interventions focused on interruption of indirect contact spread of MRSA between horses via staff and equipment and included: Temporary suspension of elective surgery; and identification and isolation of MRSA-infected horses; collaboration was initiated between authorities in animal and human public health, human medicine infection control and the veterinary hospital; extensive cleaning and disinfection was performed; basic hygiene and cleaning policies, staff training, equipment modification and interior renovation were implemented over seven months. Ten (11%) of 92 surfaces sampled between July 2008 and April 2010 tested positive for MRSA spa-type 011, seven of which were from the first of nine sampling occasions. PFGE typing showed the isolates to be the outbreak strain (9 of 10) or a closely related strain. Two new cases of MRSA infection occurred 14 and 19 months later, but had no proven connections to the outbreak cases. Conclusions Collaboration between relevant authorities and the veterinary hospital and formation of an infection control committee with an executive working group were required to move the intervention process forward. Support from hospital management and the dedication of staff were essential for the development and implementation of new, improved routines. Demonstration of the outbreak strain in the environment was useful for interventions such as improvement of cleaning routines and interior design, and increased compliance with basic hygienic precautions. The interventions led to a reduction in MRSA-positive samples and the outbreak was considered curbed as no new cases occurred for over a year. PMID:22401493

  15. Flu Outbreaks Force Schools to Adjust Plans: Classes Canceled in Some Places to Prevent Spread of Influenza

    ERIC Educational Resources Information Center

    Jacobson, Linda; Bowman, Darcia Harris

    2004-01-01

    A flu outbreak at Madison Junior High School in Ohio prompted school officials to close the building for two days. At Webber Junior High School in Fort Collins, Colorado, where absenteeism recently hit 20 percent for two bad weeks, educators were forced to slow the pace of schoolwork so sick students did not fall behind. This article reports on…

  16. Applying the One Health principles: a trans-sectoral coordination framework for preventing and responding to Rift Valley fever outbreaks.

    PubMed

    de La Rocque, S; Formenty, P

    2014-08-01

    Rift Valley fever (RVF) is a good example of a disease for which a One Health approach can significantly improve the management of outbreaks: RVF is a vector- borne zoonotic disease, its dynamics differ between eco-epidemiological patterns and are modulated by eco-climatic factors. Therefore, collaboration between sectors, disciplines and role players, as well as an understanding of the local epidemiology of the disease, are key prerequisites for proper risk assessment and outbreak control. These principles drove the Food and Agriculture Organization of the United Nations (FAO) and the World Health Organization (WHO) to develop an inter-sectoral strategic approach, with specific actions recommended for each of the four periods in the development of the outbreak (forecasting and preparedness, alert, epidemic control, post-epidemic). Through several outbreak response missions between 2006 and 2012 in various countries, an implementation framework was developed by WHO, FAO and the national authorities of affected countries and used to build national response action plans. The framework proposes a structured attribution of duty and responsibilities to committees made up of representatives of the various institutional and operational role players, and with clear mandates and terms of reference (TOR). Such an approach, ensuring real-time sharing of information, coherence in the various aspects of the response, and ownership of the strategy, has proven its efficiency. It could also be used, with appropriate adjustments in the TOR, for other zoonotic diseases. PMID:25707183

  17. Acta Tropica 104 (2007) 17 Surveillance of dengue fever cases using a novel

    E-print Network

    Severson, David

    Acta Tropica 104 (2007) 1­7 Surveillance of dengue fever cases using a novel Aedes aegypti 100 suspected dengue fever (DF) cases in county St. Patrick, Trinidad, West Indies. From the 30 that this eradication program initially sup- pressed the vector populations and prevented the spread of dengue fever (DF

  18. Outbreak of tick-borne relapsing fever at the north rim of the Grand Canyon: evidence for effectiveness of preventive measures.

    PubMed

    Paul, W S; Maupin, G; Scott-Wright, A O; Craven, R B; Dennis, D T

    2002-01-01

    An outbreak of tick-borne relapsing fever (TBRF) originating at the North Rim of Grand Canyon National Park was investigated in 1990. To determine risk factors for the disease, almost 7,000 parties of visitors were surveyed; over half responded, representing > 10,000 people. Fifteen cases of confirmed or probable TBRF were identified in visitors and 2 in employees. All patients except one experienced symptoms after overnight stays in a group of cabins that had not been rodent-proofed after a TBRF outbreak in 1973 (relative risk for visitors [RR] 8.2, 95% confidence interval [CI] 1.1-62). Seven cases of TBRF were associated with a single cabin (RR 98, 95% CI 30-219). Structural flaws and rodent nests were common in the implicated cabins and rare in unaffected cabins. This investigation suggests that measures to rodent-proof cabins at sites where TBRF is endemic prevent reinfestation of cabins by infected rodents and tick vectors, thereby preventing the spread of disease in humans. PMID:12135272

  19. In the midst of a large measles outbreak, EDs take steps to bolster screening procedures, prevent potential transmissions.

    PubMed

    2015-04-01

    A large, multi-state outbreak of measles is prompting EDs around the country to bolster their screening procedures and provide education to staff, most of whom have never seen a measles case. Dozens of people in more than 17 states have been confirmed to have the disease, with most of these cases associated with an outbreak that began at an amusement park in southern California. Measles is extremely contagious, infecting nine out of 10 people exposed to the virus if they are susceptible to the disease. In cases in which a contagious disease is suspected, experts advise emergency providers to protect themselves before proceeding to the traditional vital signs. It's a concept referred to as "vital sign zero." Once a measles case is confirmed, experts say emergency staff should isolate the patient with protection such as an N-95 mask, and inform both the hospital's infection control department and public health authorities. PMID:25844431

  20. Developing a Social Autopsy Tool for Dengue Mortality: A Pilot Study

    PubMed Central

    Arauz, María José; Ridde, Valéry; Hernández, Libia Milena; Charris, Yaneth; Carabali, Mabel; Villar, Luis Ángel

    2015-01-01

    Background Dengue fever is a public health problem in the tropical and sub-tropical world. Dengue cases have grown dramatically in recent years as well as dengue mortality. Colombia has experienced periodic dengue outbreaks with numerous dengue related-deaths, where the Santander department has been particularly affected. Although social determinants of health (SDH) shape health outcomes, including mortality, it is not yet understood how these affect dengue mortality. The aim of this pilot study was to develop and pre-test a social autopsy (SA) tool for dengue mortality. Methods and Findings The tool was developed and pre-tested in three steps. First, dengue fatal cases and ‘near misses’ (those who recovered from dengue complications) definitions were elaborated. Second, a conceptual framework on determinants of dengue mortality was developed to guide the construction of the tool. Lastly, the tool was designed and pre-tested among three relatives of fatal cases and six near misses in 2013 in the metropolitan zone of Bucaramanga. The tool turned out to be practical in the context of dengue mortality in Colombia after some modifications. The tool aims to study the social, individual, and health systems determinants of dengue mortality. The tool is focused on studying the socioeconomic position and the intermediary SDH rather than the socioeconomic and political context. Conclusions The SA tool is based on the scientific literature, a validated conceptual framework, researchers’ and health professionals’ expertise, and a pilot study. It is the first time that a SA tool has been created for the dengue mortality context. Our work furthers the study on SDH and how these are applied to neglected tropical diseases, like dengue. This tool could be integrated in surveillance systems to provide complementary information on the modifiable and avoidable death-related factors and therefore, be able to formulate interventions for dengue mortality reduction. PMID:25658485

  1. Epidemiological Trends of Dengue Disease in Colombia (2000-2011): A Systematic Review

    PubMed Central

    Villar, Luis Angel; Rojas, Diana Patricia; Besada-Lombana, Sandra; Sarti, Elsa

    2015-01-01

    A systematic literature review was conducted to describe the epidemiology of dengue disease in Colombia. Searches of published literature in epidemiological studies of dengue disease encompassing the terms “dengue”, “epidemiology,” and “Colombia” were conducted. Studies in English or Spanish published between 1 January 2000 and 23 February 2012 were included. The searches identified 225 relevant citations, 30 of which fulfilled the inclusion criteria defined in the review protocol. The epidemiology of dengue disease in Colombia was characterized by a stable “baseline” annual number of dengue fever cases, with major outbreaks in 2001–2003 and 2010. The geographical spread of dengue disease cases showed a steady increase, with most of the country affected by the 2010 outbreak. The majority of dengue disease recorded during the review period was among those <15 years of age. Gaps identified in epidemiological knowledge regarding dengue disease in Colombia may provide several avenues for future research, namely studies of asymptomatic dengue virus infection, primary versus secondary infections, and under-reporting of the disease. Improved understanding of the factors that determine disease expression and enable improvement in disease control and management is also important. PMID:25790245

  2. Analysis of Effects of Meteorological Factors on Dengue Incidence in Sri Lanka Using Time Series Data

    PubMed Central

    Goto, Kensuke; Kumarendran, Balachandran; Mettananda, Sachith; Gunasekara, Deepa; Fujii, Yoshito; Kaneko, Satoshi

    2013-01-01

    In tropical and subtropical regions of eastern and South-eastern Asia, dengue fever (DF) and dengue hemorrhagic fever (DHF) outbreaks occur frequently. Previous studies indicate an association between meteorological variables and dengue incidence using time series analyses. The impacts of meteorological changes can affect dengue outbreak. However, difficulties in collecting detailed time series data in developing countries have led to common use of monthly data in most previous studies. In addition, time series analyses are often limited to one area because of the difficulty in collecting meteorological and dengue incidence data in multiple areas. To gain better understanding, we examined the effects of meteorological factors on dengue incidence in three geographically distinct areas (Ratnapura, Colombo, and Anuradhapura) of Sri Lanka by time series analysis of weekly data. The weekly average maximum temperature and total rainfall and the total number of dengue cases from 2005 to 2011 (7 years) were used as time series data in this study. Subsequently, time series analyses were performed on the basis of ordinary least squares regression analysis followed by the vector autoregressive model (VAR). In conclusion, weekly average maximum temperatures and the weekly total rainfall did not significantly affect dengue incidence in three geographically different areas of Sri Lanka. However, the weekly total rainfall slightly influenced dengue incidence in the cities of Colombo and Anuradhapura. PMID:23671694

  3. The dengue viruses.

    PubMed Central

    Henchal, E A; Putnak, J R

    1990-01-01

    Dengue, a major public health problem throughout subtropical and tropical regions, is an acute infectious disease characterized by biphasic fever, headache, pain in various parts of the body, prostration, rash, lymphadenopathy, and leukopenia. In more severe or complicated dengue, patients present with a severe febrile illness characterized by abnormalities of hemostasis and increased vascular permeability, which in some instances results in a hypovolemic shock. Four distinct serotypes of the dengue virus (dengue-1, dengue-2, dengue-3, and dengue-4) exist, with numerous virus strains found worldwide. Molecular cloning methods have led to a greater understanding of the structure of the RNA genome and definition of virus-specific structural and nonstructural proteins. Progress towards producing safe, effective dengue virus vaccines, a goal for over 45 years, has been made. Images PMID:2224837

  4. Dengue Fever Treatment

    MedlinePLUS

    ... on. Read more information on enabling JavaScript. Dengue Fever Skip Content Marketing Share this: Main Content Area ... There is no specific treatment for classic dengue fever, and most people recover within 2 weeks. To ...

  5. Genetic and biological differentiation of dengue 3 isolates obtained from clinical cases in Java, Indonesia, 1976–1978

    Microsoft Academic Search

    E. Lee; D. J. Gubler; R. C. Weir; L. Dalgarno

    1993-01-01

    Summary Previous epidemiological, virological and clinical studies have documented a series of outbreaks of dengue fever and dengue haemorrhagic fever\\/dengue shock syndrome which occured in Java, Indonesia in 1976–1978. In the current study we compare growth characteristics in cell culture, and nucleotide sequence data for the viral prM and E genes, of five low passage DEN-3 isolates obtained during these

  6. Dengue in Cape Verde: vector control and vaccination

    E-print Network

    Rodrigues, Helena Sofia; Torres, Delfim F M

    2012-01-01

    In 2009, for the first time in Cape Verde, an outbreak of dengue was reported and over twenty thousand people were infected. Only a few prophylactic measures were taken. The effects of vector control on disease spreading, such as insecticide (larvicide and adulticide) and mechanical control, as well as an hypothetical vaccine, are estimated through simulations with the Cape Verde data.

  7. A new challenge for hospitals in southeast France: monitoring local populations of Aedes albopictus to prevent nosocomial transmission of dengue or chikungunya.

    PubMed

    Cotteaux-Lautard, Christelle; Berenger, Jean-Michel; Fusca, François; Chardon, Hubert; Simon, Fabrice; Pagès, Frederic

    2013-03-01

    Aedes albopictus was first identified in southern France in 2004, inducing an emerging risk for autochthonous transmission around imported cases of dengue or chikungunya, and also for mosquito-borne nosocomial transmission in hospitals. Aedes albopictus has been present in Marseille since September 2009 and in Aix-en-Provence since August 2010. Because of the possible admission of viremic patients with dengue or chikungunya in the hospitals of these cities, a mosquito survey was conducted in 2011 in 2 of the hospitals, with the use of mosquito traps. Aedes albopictus was detected with Eisenhans II traps and egg traps in both hospitals during the warm season. PMID:23687863

  8. Global situation of dengue and dengue haemorrhagic fever, and its emergence in the Americas.

    PubMed

    Pinheiro, F P; Corber, S J

    1997-01-01

    About two-thirds of the world's population live in areas infested with dengue vectors, mainly Aedes aegypti. All four dengue viruses are circulating, sometimes simultaneously, in most of these areas. It is estimated that up to 80 million persons become infected annually although marked underreporting results in the notification of much smaller figures. Currently dengue is endemic in all continents except Europe and epidemic dengue haemorrhagic fever (DHF) occurs in Asia, the Americas and some Pacific islands. The incidence of DHF is much greater in the Asian countries than in other regions. In Asian countries the disease continues to affect children predominantly although a marked increase in the number of DHF cases in people over 15 years old has been observed in the Philippines and Malaysia during recent years. In the 1990's DHF has continued to show a higher incidence in South-East Asia, particularly in Viet Nam and Thailand which together account for more than two-thirds of the DHF cases reported in Asia. However, an increase in the number of reported cases has been noted in the Philippines, Lao People's Democratic Republic, Cambodia, Myanmar, Malaysia, India, Singapore and Sri Lanka during the period 1991-1995 as compared to the preceding 5-year period. In the Americas, the emergence of epidemic DHF occurred in 1981 almost 30 years after its appearance in Asia, and its incidence is showing a marked upward trend. In 1981 Cuba reported the first major outbreak of DHF in the Americas, during which a total of 344,203 cases of dengue were notified, including 10,312 severe cases and 158 deaths. The DHF Cuban epidemic was associated with a strain of dengue-2 virus and it occurred four years after dengue-1 had been introduced in the island causing epidemics of dengue fever. Prior to this event suspected cases of DHF or fatal dengue cases had been reported by five countries but only a few of them fulfilled the WHO criteria for diagnosis of DHF. The outbreak in Cuba is the most important event in the history of dengue in the Americas. Subsequently to it, in every year except 1983, confirmed or suspected cases of DHF have been reported in the Region. The second major outbreak in the Americas occurred in Venezuela in 1989 and since then this country has suffered epidemics of DHF every year. Between 1981 and 1996 a total of 42,246 cases of DHF and 582 deaths were reported by 25 countries in the Americas, 53% of which originated from Venezuela and 24% from Cuba. Colombia, Nicaragua and Mexico have each reported over 1,000 cases during the period 1992-1996. About 74% of the Colombian cases and 97% of the Mexican cases were reported during 1995-1996. A main cause of the emergence of DHF in the Americas was the failure of the hemispheric campaign to eradicate Aedes aegypti. Following a successful period that resulted in the elimination of the mosquito from 18 countries by 1962, the programme began to decline and as a result there was a progressive dissemination of the vector so that by 1997 with the exception of Canada, Chile and Bermuda, all countries in the Americas are infested. Other factors contributing to the emergence/re-emergence of dengue/DHF include the rapid growth and urbanization of populations in Latin America and the Caribbean, and increased travel of persons which facilitates dissemination of dengue viruses. Presently, all four dengue serotypes are circulating in the Americas, thus increasing the risk for DHF in this region. PMID:9477544

  9. Spotlight on measles in Italy: why outbreaks of a vaccine-preventable infection continue in the 21st century.

    PubMed

    Piccirilli, Giulia; Lazzarotto, Tiziana; Chiereghin, Angela; Serra, Laura; Gabrielli, Liliana; Lanari, Marcello

    2015-03-01

    Measles is a serious infectious disease that can lead to significant morbidity and mortality. Remarkable progress has been made through measles vaccination in reducing the number of people dying from measles. In the last years, concerns about the safety of vaccines have led to decline in immunization coverage rates and new outbreaks of measles in many European countries, including Italy. We believe that it is important to reinforce the message that measles vaccine is safe and highly effective through appropriate information campaigns and public awareness. PMID:25612664

  10. Prediction of High Incidence of Dengue in the Philippines

    PubMed Central

    Buczak, Anna L.; Baugher, Benjamin; Babin, Steven M.; Ramac-Thomas, Liane C.; Guven, Erhan; Elbert, Yevgeniy; Koshute, Phillip T.; Velasco, John Mark S.; Roque, Vito G.; Tayag, Enrique A.; Yoon, In-Kyu; Lewis, Sheri H.

    2014-01-01

    Background Accurate prediction of dengue incidence levels weeks in advance of an outbreak may reduce the morbidity and mortality associated with this neglected disease. Therefore, models were developed to predict high and low dengue incidence in order to provide timely forewarnings in the Philippines. Methods Model inputs were chosen based on studies indicating variables that may impact dengue incidence. The method first uses Fuzzy Association Rule Mining techniques to extract association rules from these historical epidemiological, environmental, and socio-economic data, as well as climate data indicating future weather patterns. Selection criteria were used to choose a subset of these rules for a classifier, thereby generating a Prediction Model. The models predicted high or low incidence of dengue in a Philippines province four weeks in advance. The threshold between high and low was determined relative to historical incidence data. Principal Findings Model accuracy is described by Positive Predictive Value (PPV), Negative Predictive Value (NPV), Sensitivity, and Specificity computed on test data not previously used to develop the model. Selecting a model using the F0.5 measure, which gives PPV more importance than Sensitivity, gave these results: PPV?=?0.780, NPV?=?0.938, Sensitivity?=?0.547, Specificity?=?0.978. Using the F3 measure, which gives Sensitivity more importance than PPV, the selected model had PPV?=?0.778, NPV?=?0.948, Sensitivity?=?0.627, Specificity?=?0.974. The decision as to which model has greater utility depends on how the predictions will be used in a particular situation. Conclusions This method builds prediction models for future dengue incidence in the Philippines and is capable of being modified for use in different situations; for diseases other than dengue; and for regions beyond the Philippines. The Philippines dengue prediction models predicted high or low incidence of dengue four weeks in advance of an outbreak with high accuracy, as measured by PPV, NPV, Sensitivity, and Specificity. PMID:24722434

  11. Natural or deliberate outbreak in Pakistan: how to prevent or detect and trace its origin: biosecurity, surveillance, forensics.

    PubMed

    Shinwari, Zabta Khan; Khalil, Ali Talha; Nasim, Anwar

    2014-08-01

    Over the last few decades biosecurity and biosafety have emerged as a prominent public health concern due to some high-profile accidents. Effective strategies to deal with the outbreak, whether deliberate or non-deliberate requires a multidisciplinary approach and coordinated decision-making by various state departments such as health, forensics, agriculture, environment, intelligence, law and enforcement, etc. In a dynamic global environment and the overwhelming asymmetric threats from the non-state actors, it is of utmost importance to understand the biosecurity issues and initiate a coordinated global effort to cope with biosecurity and biosafety breaches and develop an as effective response mechanism. An attractive choice for the terrorists, state enemies and non-state actors is the use of biological weapons. An unwanted incident may not only bring chaos to the people, but also can inflict severe economic damage industrially and locally as was in the notorious foot-and-mouth disease outbreak. Because of special geopolitical compulsion, Pakistan is one of the hot spots where special action needs to be taken. The current review focuses on the various approaches, technologies that can be used to alleviate the chances of biosafety and biosecurity incident and emphasizes the role of modern technology that can be used in this regard. PMID:24942803

  12. Health Beliefs and Practices Related to Dengue Fever: A Focus Group Study

    PubMed Central

    Wong, Li Ping; AbuBakar, Sazaly

    2013-01-01

    Background This qualitative study aimed to provide an in-depth understanding of the meaning of dengue fever (DF) amongst people living in a dengue endemic region, dengue prevention and treatment-seeking behaviours. The Health Belief Model was used as a framework to explore and understand dengue prevention behaviours. Methods A total of 14 focus group discussions were conducted with 84 Malaysian citizens of different socio-demographic backgrounds between 16th December, 2011 and 12th May, 2012. Results The study revealed that awareness about DF and prevention measures were high. The pathophysiology of dengue especially dengue haemorrhagic fever (DHF) and dengue shock syndrome (DSS) were rarely known; as a result, it was seen as deadly by some but was also perceived as easily curable by others without a basis of understanding. Young adults and elderly participants had a low perception of susceptibility to DF. In general, the low perceived susceptibility emerged as two themes, namely a perceived natural ability to withstand infection and a low risk of being in contact with the dengue virus vector, Aedes spp. mosquitoes. The barriers to sustained self-prevention against dengue prevention that emerged in focus groups were: i) lack of self-efficacy, ii) lack of perceived benefit, iii) low perceived susceptibility, and iv) unsure perceived susceptibility. Low perceived benefit of continued dengue prevention practices was a result of lack of concerted action against dengue in their neighborhood. Traditional medical practices and home remedies were widely perceived and experienced as efficacious in treating DF. Conclusion Behavioural change towards attaining sustainability in dengue preventive practices may be enhanced by fostering comprehensive knowledge of dengue and a change in health beliefs. Wide use of unconventional therapy for DF warrants the need to enlighten the public to limit their reliance on unproven alternative treatments. PMID:23875045

  13. Agent-based modeling to simulate the dengue spread

    NASA Astrophysics Data System (ADS)

    Deng, Chengbin; Tao, Haiyan; Ye, Zhiwei

    2008-10-01

    In this paper, we introduce a novel method ABM in simulating the unique process for the dengue spread. Dengue is an acute infectious disease with a long history of over 200 years. Unlike the diseases that can be transmitted directly from person to person, dengue spreads through a must vector of mosquitoes. There is still no any special effective medicine and vaccine for dengue up till now. The best way to prevent dengue spread is to take precautions beforehand. Thus, it is crucial to detect and study the dynamic process of dengue spread that closely relates to human-environment interactions where Agent-Based Modeling (ABM) effectively works. The model attempts to simulate the dengue spread in a more realistic way in the bottom-up way, and to overcome the limitation of ABM, namely overlooking the influence of geographic and environmental factors. Considering the influence of environment, Aedes aegypti ecology and other epidemiological characteristics of dengue spread, ABM can be regarded as a useful way to simulate the whole process so as to disclose the essence of the evolution of dengue spread.

  14. Latest developments and future directions in dengue vaccines

    PubMed Central

    Thisyakorn, Chule

    2014-01-01

    Dengue is a mosquito-borne disease which is currently an expanding global health problem. The disease is caused by four closely related viruses, the dengue virus. There are no specific dengue therapeutics and prevention is currently limited to vector control measures. Development of an effective tetravalent dengue vaccine would therefore represent a major advance in the control of the disease and is considered a high public health priority. While a licensed dengue vaccine is not yet available, the scope and intensity of dengue vaccine development has increased dramatically in the last decade. The uniqueness of the dengue viruses and the spectrum of disease resulting from infection have made dengue vaccine development difficult. Several vaccine candidates are currently being evaluated in clinical studies. The candidate currently at the most advanced clinical development stage, a live-attenuated tetravalent vaccine based on chimeric yellow fever dengue virus, has progressed to phase III efficacy studies. Several other live-attenuated vaccines, as well as subunit, DNA and purified inactivated vaccine candidates, are at earlier stages of clinical development. Additional technological approaches, such as virus-vectored and virus-like particle-based vaccines, are under evaluation in preclinical studies. PMID:24757522

  15. Mosquito habitat and dengue risk potential in Kenya: alternative methods to traditional risk mapping techniques.

    PubMed

    Attaway, David F; Jacobsen, Kathryn H; Falconer, Allan; Manca, Germana; Rosenshein Bennett, Lauren; Waters, Nigel M

    2014-11-01

    Outbreaks, epidemics and endemic conditions make dengue a disease that has emerged as a major threat in tropical and sub-tropical countries over the past 30 years. Dengue fever creates a growing burden for public health systems and has the potential to affect over 40% of the world population. The problem being investigated is to identify the highest and lowest areas of dengue risk. This paper presents "Similarity Search", a geospatial analysis aimed at identifying these locations within Kenya. Similarity Search develops a risk map by combining environmental susceptibility analysis and geographical information systems, and then compares areas with dengue prevalence to all other locations. Kenya has had outbreaks of dengue during the past 3 years, and we identified areas with the highest susceptibility to dengue infection using bioclimatic variables, elevation and mosquito habitat as input to the model. Comparison of the modelled risk map with the reported dengue epidemic cases obtained from the open source reporting ProMED and Government news reports from 1982-2013 confirmed the high-risk locations that were used as the Similarity Search presence cells. Developing the risk model based upon the bioclimatic variables, elevation and mosquito habitat increased the efficiency and effectiveness of the dengue fever risk mapping process. PMID:25545930

  16. Dengue in India

    PubMed Central

    Gupta, Nivedita; Srivastava, Sakshi; Jain, Amita; Chaturvedi, Umesh C.

    2012-01-01

    Dengue virus belongs to family Flaviviridae, having four serotypes that spread by the bite of infected Aedes mosquitoes. It causes a wide spectrum of illness from mild asymptomatic illness to severe fatal dengue haemorrhagic fever/dengue shock syndrome (DHF/DSS). Approximately 2.5 billion people live in dengue-risk regions with about 100 million new cases each year worldwide. The cumulative dengue diseases burden has attained an unprecedented proportion in recent times with sharp increase in the size of human population at risk. Dengue disease presents highly complex pathophysiological, economic and ecologic problems. In India, the first epidemic of clinical dengue-like illness was recorded in Madras (now Chennai) in 1780 and the first virologically proved epidemic of dengue fever (DF) occurred in Calcutta (now Kolkata) and Eastern Coast of India in 1963-1964. During the last 50 years a large number of physicians have treated and described dengue disease in India, but the scientific studies addressing various problems of dengue disease have been carried out at limited number of centres. Achievements of Indian scientists are considerable; however, a lot remain to be achieved for creating an impact. This paper briefly reviews the extent of work done by various groups of scientists in this country. PMID:23041731

  17. Is dengue a threat to the blood supply?

    PubMed Central

    Teo, D; Ng, L C; Lam, S

    2009-01-01

    Dengue is the most common arthropod-borne infection worldwide, affecting at least 50 million people every year and endemic in more than 100 countries. The dengue virus is a single-stranded RNA virus with four major serotypes. Infection with one serotype confers homotypic immunity but not heterologous immunity, and secondary infection with another serotype may lead to more severe disease. The major route of transmission occurs through the Aedes aegypti mosquito vector, but dengue has also been transmitted through blood transfusion and organ transplantation. Infection results in a spectrum of clinical illness ranging from asymptomatic infection, undifferentiated fever, dengue fever, dengue haemorrhagic fever (DHF) to dengue shock syndrome (DSS). Dengue is spreading rapidly to new areas and with increasing frequency of major outbreaks. A trend has also been observed towards increasing age among infected patients. This will impact blood supply availability as more blood donors are deferred because of dengue infection or exposure to infection. The risk of transmission through transfusion of blood from asymptomatic viraemic donors will also increase. Although screening tests for dengue and effective pathogen reduction processes are now available for the blood supply, the value of implementing these costly measures needs to be carefully considered. Demand for platelets and fresh frozen plasma will rise with increasing number of DHF/DSS. Evidence-based guidelines for the clinical use of these blood components in the management of patients with DHF/DSS have not been well established, and inappropriate use will contribute to the challenges faced by blood services. PMID:19392949

  18. Dengue encephalitis-A rare manifestation of dengue fever

    PubMed Central

    Madi, Deepak; Achappa, Basavaprabhu; Ramapuram, John T; Chowta, Nityananda; Laxman, Mridula; Mahalingam, Soundarya

    2014-01-01

    The clinical spectrum of dengue fever ranges from asymptomatic infection to dengue shock syndrome. Dengue is classically considered a non-neurotropic virus. Neurological complications are not commonly seen in dengue. The neurological manifestations seen in dengue are encephalitis, meningitis, encephalopathy, stroke and Guillain-Barré syndrome. Dengue encephalitis is a rare disease. We report an interesting case of dengue encephalitis from Southern India. A 49-year-old gentleman presented with fever, altered sensorium and seizures. Dengue NS-1 antigen test was reactive. Dengue IgM was also positive. CSF PCR was negative for herpes simplex 1 & 2. Dengue encephalitis should be considered in the differential diagnosis of fever with altered sensorium, especially in countries like India where dengue is rampant. PMID:25183150

  19. An optimal control problem arising from a dengue disease transmission model.

    PubMed

    Aldila, Dipo; Götz, Thomas; Soewono, Edy

    2013-03-01

    An optimal control problem for a host-vector Dengue transmission model is discussed here. In the model, treatments with mosquito repellent are given to adults and children and those who undergo treatment are classified in treated compartments. With this classification, the model consists of 11 dynamic equations. The basic reproductive ratio that represents the epidemic indicator is obtained from the largest eigenvalue of the next generation matrix. The optimal control problem is designed with four control parameters, namely the treatment rates for children and adult compartments, and the drop-out rates from both compartments. The cost functional accounts for the total number of the infected persons, the cost of the treatment, and the cost related to reducing the drop-out rates. Numerical results for the optimal controls and the related dynamics are shown for the case of epidemic prevention and outbreak reduction strategies. PMID:23274179

  20. Reemergence of dengue virus type-3 (subtype-III) in India: Implications for increased incidence of DHF & DSS

    PubMed Central

    Dash, Paban Kumar; Parida, Man Mohan; Saxena, Parag; Abhyankar, Ajay; Singh, CP; Tewari, KN; Jana, Asha Mukul; Sekhar, K; Rao, PV Lakshmana

    2006-01-01

    Background Dengue virus infection has recently taken endemic proportion in India implicating all the four known dengue serotypes. There was a major dengue outbreak in northern India including Delhi in October- December, 2003 and again in 2004. We have carried out a detailed investigation of the 2004 outbreak by Serosurveillance, RT-PCR, nested PCR, virus isolation and genotyping. We also report the molecular epidemiological investigation of these outbreaks. Results The serological investigation of 162 suspected serum samples using an in-house dengue dipstick ELISA revealed 11%-IgM, 51%-IgG and 38%-both IgM and IgG antibody positivity. The RT-PCR analysis revealed presence of dengue RNA in 17 samples. Further subtyping and genotyping by nested PCR and nucleotide sequencing of C-prM gene junction revealed the association of subtype III of dengue virus type 3 in the outbreak. Conclusion The sudden shifting and dominance of the dengue virus serotype-3 (subtype III) replacing the earlier circulating serotype-2 (subtype IV) is a point of major concern and may be attributed to increased incidence of DHF and DSS in India. PMID:16824209

  1. Foodborne disease outbreaks in Australia, 1995 to 2000

    Microsoft Academic Search

    Craig B Dalton; Joy Gregory; Martyn D Kirk; Russell J Stafford; Rod Givney; Ed Kraa; David Gould

    2004-01-01

    Health agencies are increasingly conducting systematic reviews of foodborne disease outbreak inves- tigations to develop strategies to prevent future outbreaks. We surveyed state and territory health departments to summarise the epidemiology of foodborne disease outbreaks in Australia from 1995 to 2000. From 1995 through 2000, 293 outbreaks were identifi ed, with 214 being of foodborne origin. One hundred and seventy-four

  2. Hyperferritinaemia in Dengue Virus Infected Patients Is Associated with Immune Activation and Coagulation Disturbances

    PubMed Central

    Pannuti, Cláudio S.; Brouns, Rosalba M.; van den Berg, Riemsdijk W. A.; van den Ham, Henk-Jan; Martina, Byron E. E.; Osterhaus, Albert D. M. E.; Netea, Mihai G.; Meijers, Joost C. M.; van Gorp, Eric C. M.; Kallas, Esper G.

    2014-01-01

    Background During a dengue outbreak on the Caribbean island Aruba, highly elevated levels of ferritin were detected in dengue virus infected patients. Ferritin is an acute-phase reactant and hyperferritinaemia is a hallmark of diseases caused by extensive immune activation, such as haemophagocytic lymphohistiocytosis. The aim of this study was to investigate whether hyperferritinaemia in dengue patients was associated with clinical markers of extensive immune activation and coagulation disturbances. Methodology/Principal Findings Levels of ferritin, standard laboratory markers, sIL-2R, IL-18 and coagulation and fibrinolytic markers were determined in samples from patients with uncomplicated dengue in Aruba. Levels of ferritin were significantly increased in dengue patients compared to patients with other febrile illnesses. Moreover, levels of ferritin associated significantly with the occurrence of viraemia. Hyperferritinaemia was also significantly associated with thrombocytopenia, elevated liver enzymes and coagulation disturbances. The results were validated in a cohort of dengue virus infected patients in Brazil. In this cohort levels of ferritin and cytokine profiles were determined. Increased levels of ferritin in dengue virus infected patients in Brazil were associated with disease severity and a pro-inflammatory cytokine profile. Conclusions/Significance Altogether, we provide evidence that ferritin can be used as a clinical marker to discriminate between dengue and other febrile illnesses. The occurrence of hyperferritinaemia in dengue virus infected patients is indicative for highly active disease resulting in immune activation and coagulation disturbances. Therefore, we recommend that patients with hyperferritinaemia are monitored carefully. PMID:25299654

  3. Assessing Weather Effects on Dengue Disease in Malaysia

    PubMed Central

    Cheong, Yoon Ling; Burkart, Katrin; Leitão, Pedro J.; Lakes, Tobia

    2013-01-01

    The number of dengue cases has been increasing on a global level in recent years, and particularly so in Malaysia, yet little is known about the effects of weather for identifying the short-term risk of dengue for the population. The aim of this paper is to estimate the weather effects on dengue disease accounting for non-linear temporal effects in Selangor, Kuala Lumpur and Putrajaya, Malaysia, from 2008 to 2010. We selected the weather parameters with a Poisson generalized additive model, and then assessed the effects of minimum temperature, bi-weekly accumulated rainfall and wind speed on dengue cases using a distributed non-linear lag model while adjusting for trend, day-of-week and week of the year. We found that the relative risk of dengue cases is positively associated with increased minimum temperature at a cumulative percentage change of 11.92% (95% CI: 4.41–32.19), from 25.4 °C to 26.5 °C, with the highest effect delayed by 51 days. Increasing bi-weekly accumulated rainfall had a positively strong effect on dengue cases at a cumulative percentage change of 21.45% (95% CI: 8.96, 51.37), from 215 mm to 302 mm, with the highest effect delayed by 26–28 days. The wind speed is negatively associated with dengue cases. The estimated lagged effects can be adapted in the dengue early warning system to assist in vector control and prevention plan. PMID:24287855

  4. Evaluation of the National Notifiable Diseases Surveillance System for Dengue Fever in Taiwan, 2010–2012

    PubMed Central

    McKerr, Caoimhe; Lo, Yi-Chun; Edeghere, Obaghe; Bracebridge, Sam

    2015-01-01

    Background In Taiwan, around 1,500 cases of dengue fever are reported annually and incidence has been increasing over time. A national web-based Notifiable Diseases Surveillance System (NDSS) has been in operation since 1997 to monitor incidence and trends and support case and outbreak management. We present the findings of an evaluation of the NDSS to ascertain the extent to which dengue fever surveillance objectives are being achieved. Methodology We extracted the NDSS data on all laboratory-confirmed dengue fever cases reported during 1 January 2010 to 31 December 2012 to assess and describe key system attributes based on the Centers for Disease Control and Prevention surveillance evaluation guidelines. The system’s structure and processes were delineated and operational staff interviewed using a semi-structured questionnaire. Crude and age-adjusted incidence rates were calculated and key demographic variables were summarised to describe reporting activity. Data completeness and validity were described across several variables. Principal Findings Of 5,072 laboratory-confirmed dengue fever cases reported during 2010–2012, 4,740 (93%) were reported during July to December. The system was judged to be simple due to its minimal reporting steps. Data collected on key variables were correctly formatted and usable in > 90% of cases, demonstrating good data completeness and validity. The information collected was considered relevant by users with high acceptability. Adherence to guidelines for 24-hour reporting was 99%. Of 720 cases (14%) recorded as travel-related, 111 (15%) had an onset >14 days after return, highlighting the potential for misclassification. Information on hospitalization was missing for 22% of cases. The calculated PVP was 43%. Conclusions/Significance The NDSS for dengue fever surveillance is a robust, well maintained and acceptable system that supports the collection of complete and valid data needed to achieve the surveillance objectives. The simplicity of the system engenders compliance leading to timely and accurate reporting. Completeness of hospitalization information could be further improved to allow assessment of severity of illness. To minimize misclassification, an algorithm to accurately classify travel cases should be established. PMID:25794177

  5. Dengue disease surveillance: an updated systematic literature review

    PubMed Central

    Runge-Ranzinger, S; McCall, P J; Kroeger, A; Horstick, O

    2014-01-01

    Objectives To review the evidence for the application of tools for dengue outbreak prediction/detection and trend monitoring in passive and active disease surveillance systems in order to develop recommendations for endemic countries and identify important research needs. Methods This systematic literature review followed the protocol of a review from 2008, extending the systematic search from January 2007 to February 2013 on PubMed, EMBASE, CDSR, WHOLIS and Lilacs. Data reporting followed the PRISMA statement. The eligibility criteria comprised (i) population at risk of dengue, (ii) dengue disease surveillance, (iii) outcome of surveillance described and (iv) empirical data evaluated. The analysis classified studies based on the purpose of the surveillance programme. The main limitation of the review was expected publication bias. Results A total of 1116 papers were identified of which 36 articles were included in the review. Four cohort-based prospective studies calculated expansion factors demonstrating remarkable levels of underreporting in the surveillance systems. Several studies demonstrated that enhancement methods such as laboratory support, sentinel-based reporting and staff motivation contributed to improvements in dengue reporting. Additional improvements for passive surveillance systems are possible by incorporating simple data forms/entry/electronic-based reporting; defining clear system objectives; performing data analysis at the lowest possible level (e.g. district); seeking regular data feedback. Six studies showed that serotype changes were positively correlated with the number of reported cases or with dengue incidence, with lag times of up to 6 months. Three studies found that data on internet searches and event-based surveillance correlated well with the epidemic curve derived from surveillance data. Conclusions Passive surveillance providing the baseline for outbreak alert should be strengthened and appropriate threshold levels for outbreak alerts investigated. Additional enhancement tools such as syndromic surveillance, laboratory support and motivation strategies can be added. Appropriate alert signals need to be identified and integrated into a risk assessment tool. Shifts in dengue serotypes/genotype or electronic event-based surveillance have also considerable potential as indicator in dengue surveillance. Further research on evidence-based response strategies and cost-effectiveness is needed. Objectifs Analyser les résultats de l'application d'outils pour la prédiction/détection des épidémies de dengue et la surveillance des tendances dans les systèmes de surveillance active et passive des maladies, afin d’élaborer des recommandations pour les pays endémiques et identifier les besoins importants de recherche. PMID:24889501

  6. An update on the incidence of dengue gaining strength in Saudi Arabia and current control approaches for its vector mosquito

    PubMed Central

    2014-01-01

    Background The cases of dengue reported earlier in the late 1990s from the Kingdom of Saudi Arabia (KSA) occurred in the cities of Jeddah and Makkah. Although the kingdom has ample financial resources to establish effective control measures for the dengue vector, numerous cases of dengue occur and fluctuate in numbers from year to year. This necessitates a serious review of the current vector control strategies being practiced in order to identify the existing shortcomings. This short report provides an update on epidemiology of dengue in KSA (specifically in cities of Jeddah and Makkah) with a critical look at the current vector control strategies. Findings In 2013, 4411 cases of dengue were reported, with 8 cases of mortality. This number of dengue incidence was four times higher compared to 2012. In 2013, the highest number of 1272 dengue cases was reported in May, while the lowest number (37) of cases was reported in September. Conclusions It is evident that the control strategies of the dengue vector presently employed are inadequate. There seems to be serious deficiencies in following proper scientific procedures during field application(s) of control materials against the vector as is evident by the increases in the number of dengue cases as well as frequent outbreaks of the vector mosquito populations. In this review, some specific suggestions are made to draw attention to the relevant KSA authorities of the possible reasons behind unsuccessful control results and as to how to improve the strategy of dengue vector control in the kingdom. PMID:24890567

  7. Phylogenetic reconstruction of dengue virus type 2 in Colombia

    PubMed Central

    2012-01-01

    Background Dengue fever is perhaps the most important viral re-emergent disease especially in tropical and sub-tropical countries, affecting about 50 million people around the world yearly. In Colombia, dengue virus was first detected in 1971 and still remains as a major public health issue. Although four viral serotypes have been recurrently identified, dengue virus type 2 (DENV-2) has been involved in the most important outbreaks during the last 20 years, including 2010 when the fatality rate highly increased. As there are no major studies reviewing virus origin and genotype distribution in this country, the present study attempts to reconstruct the phylogenetic history of DENV-2 using a sequence analysis from a 224 bp PCR-amplified product corresponding to the carboxyl terminus of the envelope (E) gene from 48 Colombian isolates. Results As expected, the oldest isolates belonged to the American genotype (subtype V), but the strains collected since 1990 represent the American/Asian genotype (subtype IIIb) as previously reported in different American countries. Interestingly, the introduction of this genotype coincides with the first report of dengue hemorrhagic fever in Colombia at the end of 1989 and the increase of cases during the next years. Conclusion After replacement of the American genotype, several lineages of American/Asian subtype have rapidly spread all over the country evolving in new clades. Nevertheless, the direct association of these new variants in the raise of lethality rate observed during the last outbreak has to be demonstrated. PMID:22405440

  8. Temporal Correlations Between Mosquito-Based Dengue Virus Surveillance Measures or Indoor Mosquito Abundance and Dengue Case Numbers in Mérida City, México

    PubMed Central

    EISEN, LARS; GARCÍA-REJÓN, JULIÁN E.; GÓMEZ-CARRO, SALVADOR; VÁSQUEZ, MARÍA DEL ROSARIO NÁJERA; KEEFE, THOMAS J.; BEATY, BARRY J.; LOROÑO-PINO, MARÍA ALBA

    2014-01-01

    Surveillance of dengue virus (DENV) in Aedes (Stegomyia) aegypti (L.) females is of potential interest because human DENV infections are commonly asymptomatic, which decreases the effectiveness of dengue case surveillance to provide early warning of building outbreaks. Our primary aim was to examine if mosquito-based virological measures – monthly percentages of examined Ae. aegypti females infected with DENV or examined homes from which ?1 DENV-infected Ae. aegypti female was collected – are correlated with reported dengue cases in the same or subsequent months within study neighborhoods in Mérida City, México. The study encompassed ~30 neighborhoods in the southern and eastern parts of the city. Mosquitoes were collected monthly over a 15-month period within study homes (average of 145 homes examined per month); this produced ~5,800 Ae. aegypti females subsequently examined for DENV RNA. Although monthly dengue case numbers in the study neighborhoods varied more than 100-fold during the study period, we did not find statistically significant positive correlations between monthly data for mosquito-based DENV surveillance measures and reported dengue cases in the same or subsequent months. Monthly average temperature, rainfall, and indoor abundance of Ae. aegypti females were positively correlated (P ? 0.001) with dengue case numbers in subsequent months with lag times of 3–5, 2, and 1–2 months, respectively. However, because dengue outbreak risk is strongly influenced by serotype-specific susceptibility of the human population to DENV, the value of weather conditions and entomological indices to predict outbreaks is very limited. Potential ways to improve the sensitivity of mosquito-based DENV surveillance are discussed. PMID:25118425

  9. Acute Pancreatitis Complicating Severe Dengue

    PubMed Central

    Jain, Vishakha; Gupta, OP; Rao, Tarun; Rao, Siddharth

    2014-01-01

    Dengue is an arthropod borne viral infection endemic in tropical and subtropical continent. Severe dengue is life threatening. Various atypical presentations of dengue have been documented. But we present a rare and fatal complication of severe dengue in form of acute pancreatitis. A 27-year-old male had presented with severe dengue in decompensated shock and with pain in abdomen due to pancreatitis. The pathogenesis of acute pancreatitis in dengue is not clearly understood, but various mechanisms are postulated. The awareness and timely recognition of this complication is very important for proper management. PMID:24926168

  10. Reappearance of chikungunya, formerly called dengue, in the americas.

    PubMed

    Halstead, Scott B

    2015-04-01

    After an absence of ?200 years, chikungunya returned to the American tropics in 2013. The virus is maintained in a complex African zoonotic cycle but escapes into an urban cycle at 40- to 50-year intervals, causing global pandemics. In 1823, classical chikungunya, a viral exanthem in humans, occurred on Zanzibar, and in 1827, it arrived in the Caribbean and spread to North and South America. In Zanzibar, the disease was known as kidenga pepo, Swahili for a sudden cramp-like seizure caused by an evil spirit; in Cuba, it was known as dengue, a Spanish homonym of denga. During the eighteenth century, dengue (present-day chikungunya) was distinguished from breakbone fever (present-day dengue), another febrile exanthem. In the twentieth century, experiments resulted in the recovery and naming of present-day dengue viruses. In 1952, chikungunya virus was recovered during an outbreak in Tanzania, but by then, the virus had lost its original name to present-day dengue viruses. PMID:25816211

  11. Reappearance of Chikungunya, Formerly Called Dengue, in the Americas

    PubMed Central

    2015-01-01

    After an absence of ?200 years, chikungunya returned to the American tropics in 2013. The virus is maintained in a complex African zoonotic cycle but escapes into an urban cycle at 40- to 50-year intervals, causing global pandemics. In 1823, classical chikungunya, a viral exanthem in humans, occurred on Zanzibar, and in 1827, it arrived in the Caribbean and spread to North and South America. In Zanzibar, the disease was known as kidenga pepo, Swahili for a sudden cramp-like seizure caused by an evil spirit; in Cuba, it was known as dengue, a Spanish homonym of denga. During the eighteenth century, dengue (present-day chikungunya) was distinguished from breakbone fever (present-day dengue), another febrile exanthem. In the twentieth century, experiments resulted in the recovery and naming of present-day dengue viruses. In 1952, chikungunya virus was recovered during an outbreak in Tanzania, but by then, the virus had lost its original name to present-day dengue viruses. PMID:25816211

  12. Perceptions of representatives of a committee against dengue in the health education actions, Goiás, Brazil.

    PubMed

    Cançado, Myrella Silveira Macedo; Barbosa, Maria Alves; Teixeira, Ricardo Antônio Gonçalves; Oliveira, Ellen Synthia Fernandes de

    2014-12-01

    This study aimed to analyze how the educational actions of prevention and control of dengue are performed in Goiás, from the perspective of representatives of the State Mobilization Committee against Dengue. It is a cross-sectional descriptive-analytical study, carried out in Goiânia with 43 representatives of public-private institutions, members of the State Mobilization Committee against Dengue of Goiás, in 2013. The data collection was done through questioning about the perception of health education for dengue prevention. Data were analyzed using content analysis and the WebQDA software. Three dimensions emerged from the analysis: educational aspects, management aspects, and community involvement. Respondents recognized the importance of health education for the prevention of dengue, and of the planning to strengthen the activities of the Committee. PMID:25830742

  13. Using Geographically Weighted Regression (GWR) to Explore Spatial Varying Relationships of Immature Mosquitoes and Human Densities with the Incidence of Dengue

    PubMed Central

    Lin, Chia-Hsien; Wen, Tzai-Hung

    2011-01-01

    The only way for dengue to spread in the human population is through the human-mosquito-human cycle. Most research in this field discusses the dengue-mosquito or dengue-human relationships over a particular study area, but few have explored the local spatial variations of dengue-mosquito and dengue-human relationships within a study area. This study examined whether spatial heterogeneity exists in these relationships. We used Ordinary Least Squares (OLS) and Geographically Weighted Regression (GWR) models to analyze spatial relationships and identify the geographical heterogeneities by using the information of entomology and dengue cases in the cities of Kaohsiung and Fengshan in 2002. Our findings indicate that dengue-mosquito and dengue-human relationships were significantly spatially non-stationary. This means that in some areas higher dengue incidences were associated with higher vector/host densities, but in some areas higher incidences were related to lower vector/host densities. We demonstrated that a GWR model can be used to geographically differentiate the relationships of dengue incidence with immature mosquito and human densities. This study provides more insights into spatial targeting of intervention and control programs against dengue outbreaks within the study areas. PMID:21845159

  14. A climate-based spatiotemporal prediction for dengue fever epidemics: a case study in southern Taiwan

    NASA Astrophysics Data System (ADS)

    Yu, H.-L.; Yang, S.-J.; Lin, Y.-C.

    2012-04-01

    Dengue Fever (DF) has been identified by the World Health organization (WHO) as one of the most serious vector-borne infectious diseases in tropical and sub-tropical areas. DF has been one of the most important epidemics in Taiwan which occur annually especially in southern Taiwan during summer and autumn. Most DF studies have focused mainly on temporal DF patterns and its close association with climatic covariates, whereas few studies have investigated the spatial DF patterns (spatial dependence and clustering) and composite space-time effects of the DF epidemics. The present study proposes a spatio-temporal DF prediction approach based on stochastic Bayesian Maximum Entropy (BME) analysis. Core and site-specific knowledge bases are considered, including climate and health datasets under conditions of uncertainty, space-time dependence functions, and a Poisson regression model of climatic variables contributing to DF occurrences in southern Taiwan during 2007, when the highest number of DF cases was recorded in the history of Taiwan epidemics (over 2000). The obtained results show that the DF outbreaks in the study area are highly influenced by climatic conditions. Furthermore, the analysis can provide the required "one-week-ahead" outbreak warnings based on spatio-temporal predictions of DF distributions. Therefore, the proposed analysis can provide the Taiwan Disease Control Agency with a valuable tool to timely identify, control, and even efficiently prevent DF spreading across space-time.

  15. Use of insecticide-treated house screens to reduce infestations of dengue virus vectors, Mexico.

    PubMed

    Manrique-Saide, Pablo; Che-Mendoza, Azael; Barrera-Perez, Mario; Guillermo-May, Guillermo; Herrera-Bojorquez, Josue; Dzul-Manzanilla, Felipe; Gutierrez-Castro, Cipriano; Lenhart, Audrey; Vazquez-Prokopec, Gonzalo; Sommerfeld, Johannes; McCall, Philip J; Kroeger, Axel; Arredondo-Jimenez, Juan I

    2015-02-01

    Dengue prevention efforts rely on control of virus vectors. We investigated use of insecticide-treated screens permanently affixed to windows and doors in Mexico and found that the screens significantly reduced infestations of Aedes aegypti mosquitoes in treated houses. Our findings demonstrate the value of this method for dengue virus vector control. PMID:25625483

  16. Use of Insecticide-Treated House Screens to Reduce Infestations of Dengue Virus Vectors, Mexico

    PubMed Central

    Manrique-Saide, Pablo; Che-Mendoza, Azael; Barrera-Perez, Mario; Guillermo-May, Guillermo; Herrera-Bojorquez, Josue; Dzul-Manzanilla, Felipe; Gutierrez-Castro, Cipriano; Lenhart, Audrey; Vazquez-Prokopec, Gonzalo; Sommerfeld, Johannes; McCall, Philip J.; Kroeger, Axel

    2015-01-01

    Dengue prevention efforts rely on control of virus vectors. We investigated use of insecticide-treated screens permanently affixed to windows and doors in Mexico and found that the screens significantly reduced infestations of Aedes aegypti mosquitoes in treated houses. Our findings demonstrate the value of this method for dengue virus vector control. PMID:25625483

  17. International Dispersal of Dengue through Air Travel: Importation Risk for Europe

    PubMed Central

    Semenza, Jan C.; Sudre, Bertrand; Miniota, Jennifer; Rossi, Massimiliano; Hu, Wei; Kossowsky, David; Suk, Jonathan E.; Van Bortel, Wim; Khan, Kamran

    2014-01-01

    Background The worldwide distribution of dengue is expanding, in part due to globalized traffic and trade. Aedes albopictus is a competent vector for dengue viruses (DENV) and is now established in numerous regions of Europe. Viremic travellers arriving in Europe from dengue-affected areas of the world can become catalysts of local outbreaks in Europe. Local dengue transmission in Europe is extremely rare, and the last outbreak occurred in 1927–28 in Greece. However, autochthonous transmission was reported from France in September 2010, and from Croatia between August and October 2010. Methodology We compiled data on areas affected by dengue in 2010 from web resources and surveillance reports, and collected national dengue importation data. We developed a hierarchical regression model to quantify the relationship between the number of reported dengue cases imported into Europe and the volume of airline travellers arriving from dengue-affected areas internationally. Principal Findings In 2010, over 5.8 million airline travellers entered Europe from dengue-affected areas worldwide, of which 703,396 arrived at 36 airports situated in areas where Ae. albopictus has been recorded. The adjusted incidence rate ratio for imported dengue into European countries was 1.09 (95% CI: 1.01–1.17) for every increase of 10,000 travellers; in August, September, and October the rate ratios were 1.70 (95%CI: 1.23–2.35), 1.46 (95%CI: 1.02–2.10), and 1.35 (95%CI: 1.01–1.81), respectively. Two Italian cities where the vector is present received over 50% of all travellers from dengue-affected areas, yet with the continuing vector expansion more cities will be implicated in the future. In fact, 38% more travellers arrived in 2013 into those parts of Europe where Ae. albopictus has recently been introduced, compared to 2010. Conclusions The highest risk of dengue importation in 2010 was restricted to three months and can be ranked according to arriving traveller volume from dengue-affected areas into cities where the vector is present. The presence of the vector is a necessary, but not sufficient, prerequisite for DENV onward transmission, which depends on a number of additional factors. However, our empirical model can provide spatio-temporal elements to public health interventions. PMID:25474491

  18. Dengue viruses – an overview

    PubMed Central

    Bäck, Anne Tuiskunen; Lundkvist, Åke

    2013-01-01

    Dengue viruses (DENVs) cause the most common arthropod-borne viral disease in man with 50–100 million infections per year. Because of the lack of a vaccine and antiviral drugs, the sole measure of control is limiting the Aedes mosquito vectors. DENV infection can be asymptomatic or a self-limited, acute febrile disease ranging in severity. The classical form of dengue fever (DF) is characterized by high fever, headache, stomach ache, rash, myalgia, and arthralgia. Severe dengue, dengue hemorrhagic fever (DHF), and dengue shock syndrome (DSS) are accompanied by thrombocytopenia, vascular leakage, and hypotension. DSS, which can be fatal, is characterized by systemic shock. Despite intensive research, the underlying mechanisms causing severe dengue is still not well understood partly due to the lack of appropriate animal models of infection and disease. However, even though it is clear that both viral and host factors play important roles in the course of infection, a fundamental knowledge gap still remains to be filled regarding host cell tropism, crucial host immune response mechanisms, and viral markers for virulence. PMID:24003364

  19. Fault tree analysis of the causes of waterborne outbreaks.

    PubMed

    Risebro, Helen L; Doria, Miguel F; Andersson, Yvonne; Medema, Gertjan; Osborn, Keith; Schlosser, Olivier; Hunter, Paul R

    2007-01-01

    Prevention and containment of outbreaks requires examination of the contribution and interrelation of outbreak causative events. An outbreak fault tree was developed and applied to 61 enteric outbreaks related to public drinking water supplies in the EU. A mean of 3.25 causative events per outbreak were identified; each event was assigned a score based on percentage contribution per outbreak. Source and treatment system causative events often occurred concurrently (in 34 outbreaks). Distribution system causative events occurred less frequently (19 outbreaks) but were often solitary events contributing heavily towards the outbreak (a mean % score of 87.42). Livestock and rainfall in the catchment with no/inadequate filtration of water sources contributed concurrently to 11 of 31 Cryptosporidium outbreaks. Of the 23 protozoan outbreaks experiencing at least one treatment causative event, 90% of these events were filtration deficiencies; by contrast, for bacterial, viral, gastroenteritis and mixed pathogen outbreaks, 75% of treatment events were disinfection deficiencies. Roughly equal numbers of groundwater and surface water outbreaks experienced at least one treatment causative event (18 and 17 outbreaks, respectively). Retrospective analysis of multiple outbreaks of enteric disease can be used to inform outbreak investigations, facilitate corrective measures, and further develop multi-barrier approaches. PMID:17890833

  20. Dengue-associated kidney disease

    PubMed Central

    J Lizarraga, Karlo; Nayer, Ali

    2014-01-01

    Context: A mosquito-borne viral illness highly prevalent in the tropics and subtropics, dengue is considered a major global health threat by the World Health Organization. Evidence Acquisitions: Directory of Open Access Journals (DOAJ), Google Scholar, PubMed (NLM), LISTA (EBSCO) and Web of Science have been searched. Results: An RNA virus from the genus Flavivirus, dengue virus is transmitted by Aedes aegypti,the yellow fever mosquito. Dengue is asymptomatic in as many as one half of infected individuals. Dengue fever is an acute febrile illness accompanied by constitutional symptoms. Dengue hemorrhagic fever and dengue shock syndrome are the severe forms of dengue infection.Dengue infection has been associated with a variety of renal disorders. Acute renal failure is a potential complication of severe dengue infection and is typically associated with hypotension, rhabdomyolysis, or hemolysis. Acute renal failure complicates severe dengue infection in 2-5% of the cases and carries a high mortality rate. Proteinuria has been detected in as high as 74% of patients with severe dengue infection. Hematuria has been reported in up to 12.5% of patients. Various types of glomerulonephritis have been reported during or shortly after dengue infection in humans and mouse models of dengue infection. Mesangial proliferation and immune complex deposition are the dominant histologic features of dengue-associated glomerulonephritis. On a rare occasion, dengue infection is associated with systemic autoimmune disorders involving the kidneys. Conclusions: In the vast majority of cases, dengue infection and associated renal disorders are self-limited. PMID:24772398

  1. Characterization of the Temporal and Spatial Dynamics of the Dengue Epidemic in Northern Sri Lanka

    NASA Astrophysics Data System (ADS)

    Anno, S.; Imaoka, K.; Tadono, T.; Igarashi, T.; Sivaganesh, S.; Kannathasan, S.; Kumaran, V.; Surendran, S.

    2014-11-01

    Dengue outbreaks are affected by biological, ecological, socio-economic and demographic factors that vary over time and space. These factors have been examined separately, with limited success, and still require clarification. The present study aimed to investigate the spatial and temporal relationships between these factors and dengue outbreaks in the northern region of Sri Lanka. Remote sensing (RS) data gathered from a plurality of satellites: TRMM TMI, Aqua AMSR-E, GCOM-W AMSR2, DMSP SSM/I, DMSP SSMIS, NOAA-19 AMSU, MetOp-A AMSU and GEO IR were used to develop an index comprising rainfall. Humidity (total precipitable water, or vertically integrated water vapor amount) and temperature (surface temperature) data were acquired from the JAXA Satellite Monitoring for Environmental Studies (JASMES) portal which were retrieved and processed from the Aqua/MODIS and Terra/MODIS data. RS data gathered by ALOS/AVNIR-2 were used to detect urbanization, and a digital land cover map was used to extract land cover information. Other data on relevant factors and dengue outbreaks were collected through institutions and extant databases. The analyzed RS data and databases were integrated into geographic information systems, enabling both spatial association analysis and spatial statistical analysis. Our findings show that the combination of ecological factors derived from RS data and socio-economic and demographic factors is suitable for predicting spatial and temporal patterns of dengue outbreaks.

  2. Aedes aegypti in Brazil: genetically differentiated populations with high susceptibility to dengue and yellow fever viruses

    Microsoft Academic Search

    R Lourenço-de-Oliveira; M Vazeille; A. M. B de Filippis; A. B Failloux

    2004-01-01

    Aedes aegypti was eliminated from Brazil in 1955, but re-infested the country in the 1970s. Dengue outbreaks have occurred since 1981 and became endemic in several cities in Brazil after 1986. Urban yellow fever has not occurred since 1942, and only jungle yellow fever cases have been reported. A population genetic analysis using isoenzyme variation combined with an evaluation of

  3. Epidemic dengue 2 in the city of Djibouti 1991–1992

    Microsoft Academic Search

    Guénaël R. Kodier; Duane J. Gubler; Stanton E. Cope; C. Bruce Cropp; Atef K. Soliman; Dominique Polycarpe; Mohamed A. Abdourhaman; Jean-Pierre Parra; Jérôme Maslin; Ray R. Arthur

    1996-01-01

    From October 1991 to February 1992, an outbreak of acute fever (in which thick blood films were negative for malaria) spread rapidly in the city of Djibouti, Djibouti Republic, affecting all age groups and both nationals and foreigners. The estimated number of cases was 12 000. The clinical features were consistent with a non-haemorrhagic dengue-like illness. Serum samples from 91

  4. Dengue 3 epidemic, Havana, 2001.

    PubMed

    Peláez, Otto; Guzmán, María G; Kourí, Gustavo; Pérez, Raúl; San Martín, José L; Vázquez, Susana; Rosario, Delfina; Mora, Regla; Quintana, Ibrahim; Bisset, Juan; Cancio, Reynel; Masa, Ana M; Castro, Osvaldo; González, Daniel; Avila, Luis C; Rodríguez, Rosmari; Alvarez, Mayling; Pelegrino, Jose L; Bernardo, Lídice; Prado, Irina

    2004-04-01

    In June 2001, dengue transmission was detected in Havana, Cuba; 12,889 cases were reported. Dengue 3, the etiologic agent of the epidemic, caused the dengue hemorrhagic fever only in adults, with 78 cases and 3 deaths. After intensive vector control efforts, no new cases have been detected. PMID:15200868

  5. Assessing the Relationship between Vector Indices and Dengue Transmission: A Systematic Review of the Evidence

    PubMed Central

    Bowman, Leigh R.; Runge-Ranzinger, Silvia; McCall, P. J.

    2014-01-01

    Background Despite doubts about methods used and the association between vector density and dengue transmission, routine sampling of mosquito vector populations is common in dengue-endemic countries worldwide. This study examined the evidence from published studies for the existence of any quantitative relationship between vector indices and dengue cases. Methodology/Principal Findings From a total of 1205 papers identified in database searches following Cochrane and PRISMA Group guidelines, 18 were included for review. Eligibility criteria included 3-month study duration and dengue case confirmation by WHO case definition and/or serology. A range of designs were seen, particularly in spatial sampling and analyses, and all but 3 were classed as weak study designs. Eleven of eighteen studies generated Stegomyia indices from combined larval and pupal data. Adult vector data were reported in only three studies. Of thirteen studies that investigated associations between vector indices and dengue cases, 4 reported positive correlations, 4 found no correlation and 5 reported ambiguous or inconclusive associations. Six out of 7 studies that measured Breteau Indices reported dengue transmission at levels below the currently accepted threshold of 5. Conclusions/Significance There was little evidence of quantifiable associations between vector indices and dengue transmission that could reliably be used for outbreak prediction. This review highlighted the need for standardized sampling protocols that adequately consider dengue spatial heterogeneity. Recommendations for more appropriately designed studies include: standardized study design to elucidate the relationship between vector abundance and dengue transmission; adult mosquito sampling should be routine; single values of Breteau or other indices are not reliable universal dengue transmission thresholds; better knowledge of vector ecology is required. PMID:24810901

  6. Simultaneous circulation of genotypes I and III of dengue virus 3 in Colombia

    PubMed Central

    Usme-Ciro, Jose A; Mendez, Jairo A; Tenorio, Antonio; Rey, Gloria J; Domingo, Cristina; Gallego-Gomez, Juan C

    2008-01-01

    Background Dengue is a major health problem in tropical and subtropical regions. In Colombia, dengue viruses (DENV) cause about 50,000 cases annually, 10% of which involve Dengue Haemorrhagic Fever/Dengue Shock Syndrome. The picture is similar in other surrounding countries in the Americas, with recent outbreaks of severe disease, mostly associated with DENV serotype 3, strains of the Indian genotype, introduced into the Americas in 1994. Results The analysis of the 3'end (224 bp) of the envelope gene from 32 DENV-3 strains recently recovered in Colombia confirms the circulation of the Indian genotype, and surprisingly the co-circulation of an Asian-Pacific genotype only recently described in the Americas. Conclusion These results have important implications for epidemiology and surveillance of DENV infection in Central and South America. Molecular surveillance of the DENV genotypes infecting humans could be a very valuable tool for controlling/mitigating the impact of the DENV infection. PMID:18764951

  7. A 21st century approach to tackling dengue: Crowdsourced surveillance, predictive mapping and tailored communication.

    PubMed

    Lwin, May O; Vijaykumar, Santosh; Fernando, Owen Noel Newton; Cheong, Siew Ann; Rathnayake, Vajira Sampath; Lim, Gentatsu; Theng, Yin-Leng; Chaudhuri, Subhasis; Foo, Schubert

    2013-10-23

    This paper describes a social media system to prevent dengue in Sri Lanka and potentially in the rest of the South and Southeast Asia regions. The system integrates three concepts of public health prevention that have thus far been implemented only in silos. First, the predictive surveillance component uses a computer simulation to forewarn health authorities and the general public about impending disease outbreaks. The civic engagement component allows the general public to use social media tools to interact and engage with health authorities by aiding them in surveillance efforts by reporting symptoms, mosquito bites and breeding sites using smartphone technologies. The health communication component utilizes citizen data gathered from the first two components to disseminate customized health awareness messages to enhance knowledge and increase preventive behaviors among citizens. The system, known as "Mo-Buzz," will be made available on a host of digital platforms like simple mobile phones, smart phones and a website. We present challenges and lessons learnt including content validation, stakeholder collaborations and applied trans-disciplinary research. PMID:24161879

  8. Outbreak of Nosocomial Listeriosis — Texas, 2010

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background: Invasive listeriosis is a potentially fatal foodborne disease caused by Listeria monocytogenes. In February 2010, a listeriosis cluster was identified in Texas. We investigated to confirm the outbreak, identify the source, and prevent additional infections. Methods: All clinical isol...

  9. Novel, Meso-Substituted Cationic Porphyrin Molecule for Photo-Mediated Larval Control of the Dengue Vector Aedes aegypti

    PubMed Central

    Lucantoni, Leonardo; Magaraggia, Michela; Lupidi, Giulio; Ouedraogo, Robert Kossivi; Coppellotti, Olimpia; Esposito, Fulvio; Fabris, Clara; Jori, Giulio; Habluetzel, Annette

    2011-01-01

    Background Control of the mosquito vector population is the most effective strategy currently available for the prevention of dengue fever and the containment of outbreaks. Photo-activated oxidants may represent promising tools for developing effective, safe and ecofriendly novel larvicides. The purpose of this study was to evaluate the potential of the synthetic meso-substituted porphyrin meso-tri(N-methylpyridyl), meso-mono(N-tetradecylpyridyl)porphine (C14) as a photoactivatable larvicide against the dengue vector Aedes (Stegomyia) aegypti. Methodology The photophysical and photochemical properties of the C14 molecule were assessed spectrophotometrically. Photomediated larvicidal efficacy, route of intake and site of action were determined on Ae. aegypti larvae by laboratory bioassays and fluorescence microscopy. Using powdered food pellet for laboratory rodents (a common larval food used in the laboratory) as a carrier for C14, loading-release dynamics, larvicidal efficacy and residual activity of the C14-carrier complex were investigated. Main Findings The C14 molecule was found to exert a potent photosensitizing activity on Ae. aegypti larvae. At irradiation intervals of 12 h and 1 h, at a light intensity of 4.0 mW/cm2, which is 50–100 times lower than that of natural sunlight, LC50 values of 0.1 µM (0.15 mg/l) and 0.5 µM (0.77 mg/l) were obtained, respectively. The molecule was active after ingestion by the larvae and caused irreversible, lethal damage to the midgut and caecal epithelia. The amphiphilic nature of C14 allowed a formulate to be produced that not only was as active against the larvae as C14 in solution, but also possessed a residual activity of at least two weeks, in laboratory conditions. Conclusions The meso-substituted synthetic porphyrin C14, thanks to its photo-sensitizing properties represents an attractive candidate for the development of novel photolarvicides for dengue vector control. PMID:22206031

  10. Describing the Breakbone Fever: IDODEN, an Ontology for Dengue Fever

    PubMed Central

    Mitraka, Elvira; Topalis, Pantelis; Dritsou, Vicky; Dialynas, Emmanuel; Louis, Christos

    2015-01-01

    Background Ontologies represent powerful tools in information technology because they enhance interoperability and facilitate, among other things, the construction of optimized search engines. To address the need to expand the toolbox available for the control and prevention of vector-borne diseases we embarked on the construction of specific ontologies. We present here IDODEN, an ontology that describes dengue fever, one of the globally most important diseases that are transmitted by mosquitoes. Methodology/Principal Findings We constructed IDODEN using open source software, and modeled it on IDOMAL, the malaria ontology developed previously. IDODEN covers all aspects of dengue fever, such as disease biology, epidemiology and clinical features. Moreover, it covers all facets of dengue entomology. IDODEN, which is freely available, can now be used for the annotation of dengue-related data and, in addition to its use for modeling, it can be utilized for the construction of other dedicated IT tools such as decision support systems. Conclusions/Significance The availability of the dengue ontology will enable databases hosting dengue-associated data and decision-support systems for that disease to perform most efficiently and to link their own data to those stored in other independent repositories, in an architecture- and software-independent manner. PMID:25646954

  11. [Modern immunological and clinical determinants of virus dengue infection].

    PubMed

    P?usa, Tadeusz

    2014-11-01

    The growing problem of widespread viral infections is a challenge for modern medicine. Emerging reports of dengue virus infections in Europe create a new epidemic problem. The virus responsible for causing the symptoms of the disease is transmitted by mosquitoes. Over 50% of the world's population lives in areas where the risk of dengue feveris high. In total, according to WHO, infected with dengue is 2.4 million people and outbreaks of endemic diseases are present in 100 countries that threaten the 2.5 billion population. There are four serotypes of dengue virus, which belong to the family Flaviviridae and the type of Flavirus. Serotypes are known as DENV-1, DENV-2, DENV-3 and DENV-4. Contact each of the serotypes of the virus causes long-lasting resistance to the other, and each of them is responsible for the induction of disease epidemics, including severe cases. In the first stage of the disease should seek to replace lost fluids and electrolytes. Because of the elevated body temperature is recommended to administer paracetamol formulations and the use of cold compresses. Contraindicated is the use of aspirin and non-steroidal anti-inflammatory drugs. In severe forms of dengue patients absolutely should be hospitalized and treatment in the intensive care centers. In the treatment of shock, it is recommended that the administration of isotonic crystalloid fluids at 5-10 ml/kg/hr. under the control of hematocrit and fill peripheral microcirculation. The administration of blood products for the large current is required to control bleeding. Dengue vaccine containing DEN-DEN chimeras is still at the stage of preclinical studies. PMID:25546995

  12. Leptospirosis prevalence in patients with initial diagnosis of dengue.

    PubMed

    Dircio Montes Sergio, A; González Figueroa, E; María Saadia, Verdalet Guzmán; Elizabeth, Soler Huerta; Beatriz, Rivas Sánchez; Altuzar Aguilar Víctor, M; Navarrete Espinosa, J

    2012-01-01

    Objective. To determine the prevalence of leptospirosis in patients from Veracruz with initial diagnosis of dengue and its association with risk factors. Materials and Methods. Transversal study in patients who sought medical attention under the suspicion of dengue. Backgrounds were researched and blood samples were drawn to determine dengue (NS1, RT-PCR) and leptospirosis (IFI). Simple frequencies, central tendency and dispersion measures, and prevalence and trust intervals at 95% (IC95%) were obtained. Prevalence reasons (RP) and IC(95%) were obtained and a multivariate logistic model was applied, using SPSS?V15. Results. 171 patients were included, 56% women (32 ± 14 years) and 44% men (32 ± 17 years). 48% of the cases (IC95%?40.5-55.4) was positive to dengue, with a cut point of 1?:?80, seroprevalence for leptospirosis was of 6% (IC(95%)?2.7-10); 12% (IC95%?7-16.5) was positive to both pathologies and 34% was negative to both tests. Although the largest number of isolations corresponded to serotype 2, the four dengue virus serotypes were identified. In the bivariate analysis, overcrowding RP?=?1.33, (IC?=?0.46-3.5), bathing in rivers (RP?=?1.31, IC?=?0.13-7.4), and walking barefoot (RP?=?1.39, IC?=?0.58-3.3) were the variables associated with leptospirosis, although the relation was not statistically significant. Conclusions. Leptospirosis prevalence in subjects under suspicion of dengue fever is high, as well as the coincidence of both infections. The results show the coexistence of overlapped outbreaks of several diseases sharing the side of transmission. It is necessary the intentional search of other pathologies, such as influenza, rickettsiosis, and brucella, among others. PMID:22685476

  13. Leptospirosis Prevalence in Patients with Initial Diagnosis of Dengue

    PubMed Central

    Dircio Montes Sergio, A.; González Figueroa, E.; María Saadia, Verdalet Guzmán; Elizabeth, Soler Huerta; Beatriz, Rivas Sánchez; Altuzar Aguilar Víctor, M.; Navarrete Espinosa, J.

    2012-01-01

    Objective. To determine the prevalence of leptospirosis in patients from Veracruz with initial diagnosis of dengue and its association with risk factors. Materials and Methods. Transversal study in patients who sought medical attention under the suspicion of dengue. Backgrounds were researched and blood samples were drawn to determine dengue (NS1, RT-PCR) and leptospirosis (IFI). Simple frequencies, central tendency and dispersion measures, and prevalence and trust intervals at 95% (IC95%) were obtained. Prevalence reasons (RP) and IC95% were obtained and a multivariate logistic model was applied, using SPSS?V15. Results. 171 patients were included, 56% women (32 ± 14 years) and 44% men (32 ± 17 years). 48% of the cases (IC95%?40.5–55.4) was positive to dengue, with a cut point of 1?:?80, seroprevalence for leptospirosis was of 6% (IC95%?2.7–10); 12% (IC95%?7–16.5) was positive to both pathologies and 34% was negative to both tests. Although the largest number of isolations corresponded to serotype 2, the four dengue virus serotypes were identified. In the bivariate analysis, overcrowding RP?=?1.33, (IC?=?0.46–3.5), bathing in rivers (RP?=?1.31, IC?=?0.13–7.4), and walking barefoot (RP?=?1.39, IC?=?0.58–3.3) were the variables associated with leptospirosis, although the relation was not statistically significant. Conclusions. Leptospirosis prevalence in subjects under suspicion of dengue fever is high, as well as the coincidence of both infections. The results show the coexistence of overlapped outbreaks of several diseases sharing the side of transmission. It is necessary the intentional search of other pathologies, such as influenza, rickettsiosis, and brucella, among others. PMID:22685476

  14. The interaction between claudin-1 and dengue viral prM/M protein for its entry.

    PubMed

    Che, Pulin; Tang, Hengli; Li, Qianjun

    2013-11-01

    Dengue disease is becoming a huge public health concern around the world as more than one-third of the world's population living in areas at risk of infection. In an effort to assess host factors interacting with dengue virus, we identified claudin-1, a major tight junction component, as an essential cell surface protein for dengue virus entry. When claudin-1 was knocked down in Huh 7.5 cells via shRNA, the amount of dengue virus entering host cells was reduced. Consequently, the progeny virus productions were decreased and dengue virus-induced CPE was prevented. Furthermore, restoring the expression of claudin-1 in the knockdown cells facilitated dengue virus entry. The interaction between claudin-1 and dengue viral prM protein was further demonstrated using the pull-down assay. Deletion of the extracellular loop 1 (ECL1) of claudin-1 abolished such interaction, so did point mutations C54A, C64A and I32M on ECL1. These results suggest that the interaction between viral protein prM and host protein claudin-1 was essential for dengue entry. Since host and viral factors involved in virus entry are promising therapeutic targets, determining the essential role of claudin-1 could lead to the discovery of entry inhibitors with attractive therapeutic potential against dengue disease. PMID:24074594

  15. Use of Multiple Data Sources to Estimate the Economic Cost of Dengue Illness in Malaysia

    PubMed Central

    Shepard, Donald S.; Undurraga, Eduardo A.; Lees, Rosemary Susan; Halasa, Yara; Lum, Lucy Chai See; Ng, Chiu Wan

    2012-01-01

    Dengue represents a substantial burden in many tropical and sub-tropical regions of the world. We estimated the economic burden of dengue illness in Malaysia. Information about economic burden is needed for setting health policy priorities, but accurate estimation is difficult because of incomplete data. We overcame this limitation by merging multiple data sources to refine our estimates, including an extensive literature review, discussion with experts, review of data from health and surveillance systems, and implementation of a Delphi process. Because Malaysia has a passive surveillance system, the number of dengue cases is under-reported. Using an adjusted estimate of total dengue cases, we estimated an economic burden of dengue illness of US$56 million (Malaysian Ringgit MYR196 million) per year, which is approximately US$2.03 (Malaysian Ringgit 7.14) per capita. The overall economic burden of dengue would be even higher if we included costs associated with dengue prevention and control, dengue surveillance, and long-term sequelae of dengue. PMID:23033404

  16. Aedes aegypti larval indices and risk for dengue epidemics.

    PubMed

    Sanchez, Lizet; Vanlerberghe, Veerle; Alfonso, Lázara; Marquetti, Maria del Carmen; Guzman, Maria Guadalupe; Bisset, Juan; van der Stuyft, Patrick

    2006-05-01

    We assessed in a case-control study the test-validity of Aedes larval indices for the 2000 Havana outbreak. "Cases" were blocks where a dengue fever patient lived during the outbreak. "Controls" were randomly sampled blocks. Before, during, and after the epidemic, we calculated Breteau index (BI) and house index at the area, neighborhood, and block level. We constructed receiver operating characteristic (ROC) curves to determine their performance as predictors of dengue transmission. We observed a pronounced effect of the level of measurement. The BI(max) (maximum block BI in a radius of 100 m) at 2-month intervals had an area under the ROC curve of 71%. At a cutoff of 4.0, it significantly (odds ratio 6.00, p<0.05) predicted transmission with 78% sensitivity and 63% specificity. Analysis of BI at the local level, with human-defined boundaries, could be introduced in control programs to identify neighborhoods at high risk for dengue transmission. PMID:16704841

  17. Optimization model of vaccination strategy for dengue transmission

    NASA Astrophysics Data System (ADS)

    Widayani, H.; Kallista, M.; Nuraini, N.; Sari, M. Y.

    2014-02-01

    Dengue fever is emerging tropical and subtropical disease caused by dengue virus infection. The vaccination should be done as a prevention of epidemic in population. The host-vector model are modified with consider a vaccination factor to prevent the occurrence of epidemic dengue in a population. An optimal vaccination strategy using non-linear objective function was proposed. The genetic algorithm programming techniques are combined with fourth-order Runge-Kutta method to construct the optimal vaccination. In this paper, the appropriate vaccination strategy by using the optimal minimum cost function which can reduce the number of epidemic was analyzed. The numerical simulation for some specific cases of vaccination strategy is shown.

  18. Dengue Serosurvey in Sint Eustatius

    PubMed Central

    Leslie, Teresa; Martin, Nicholas J.; Jack-Roosberg, Carol; Odongo, George; Beausoleil, Edwin; Tuck, Jennifer; Raviprakash, Kanakatte; Kochel, Tadeusz J.

    2014-01-01

    Four distinct serotypes of dengue viruses (DENV) are the cause of re-emerging dengue fever (DF) and dengue hemorrhagic fever (DHF). Dengue circulation in the Caribbean has gone from none or single serotype to multiple serotypes co-circulating with reports of continuing cycles of progressively more severe disease in the region. Few studies have investigated dengue on Sint Eustatius. Blood samples were collected to determine the prevalence of antibodies against dengue in the Sint Eustatius population. Greater than 90% of the serum samples (184 of 204) were positive for anti-flavivirus antibodies by enzyme linked immunosorbance assay (ELISA). Plaque reduction neutralization test (PRNT), specific for dengue viruses, showed that 171 of these 184 flavivirus antibody positive sera had a neutralization titer against one or more DENV serotypes. A majority of the sera (62%) had neutralizing antibody to all four dengue serotypes. Only 26 PRNT positive sera (15%) had monotypic dengue virus neutralizing antibody, most of which (20 of 26) were against DENV2. Evidence of infection with all four serotypes was observed across all age groups except in the youngest age group (10–19 years) which contained only DENV2 positive individuals. In a multiple logistic regression model, only the length of residence on the island was a predictor of a positive dengue PRNT50 result. To our knowledge this is the first dengue serosurveillance study conducted on Sint Eustatius since the 1970s. The lack of antibodies to the DEN1, 3, and 4 in the samples collected from participants under 20 years of age suggests that only DEN2 has circulated on island since the early 1990s. The high prevalence of antibodies against dengue (83.8%) and the observation that the length of time on the island was the strongest predictor of infection suggests dengue is endemic on Sint Eustatius and a public health concern that warrants further investigation. PMID:24914538

  19. Dengue fever in patients under biologics.

    PubMed

    Deligny, Christophe; de Bandt, Michel; Dehlinger, Véronique; Numéric, Patrick; Cabié, André; Lombard, Frederic; Polomat, Katlyne; JeanBaptiste, Georges; Arfi, Serge

    2014-11-01

    Dengue fever (DF) is an epidemic viral mosquito-borne infection limited to tropical and subtropical countries. Biological therapies have been frequently used for the last 15 years in the treatment of inflammatory rheumatic conditions like rheumatoid arthritis. However, no data is available regarding the characteristics of this infection in patients on biological therapy. Yet, numerous patients on biotherapy have holidays in countries where DF exists. Moreover, the mosquitoes Aedes albopictus, vector of this viral disease, is now found in some developed countries such as southern Europe and the USA, allowing the possibility of a DF outbreak. We conducted a survey of individuals on biotherapy and described a case series of the patients experiencing DF. Our 8 patients on biotherapy (anti-TNF, n=6; rituximab, n=2) for a rheumatic condition did not experience severe DF. PMID:25200649

  20. Dengue Virus Tropism in Humanized Mice Recapitulates Human Dengue Fever

    PubMed Central

    Mota, Javier; Rico-Hesse, Rebeca

    2011-01-01

    Animal models of dengue virus disease have been very difficult to develop because of the virus' specificity for infection and replication in certain human cells. We developed a model of dengue fever in immunodeficient mice transplanted with human stem cells from umbilical cord blood. These mice show measurable signs of dengue disease as in humans (fever, viremia, erythema and thrombocytopenia), and after infection with the most virulent strain of dengue serotype 2, humanized mice showed infection in human cells in bone marrow, spleen and blood. Cytokines and chemokines were secreted by these human cells into the mouse bloodstream. We demonstrated that the pathology of dengue virus infection in these mice follows that reported in human patients, making this the first valid and relevant model for studying dengue fever pathogenesis in humans. PMID:21695193

  1. Environmental data analysis and remote sensing for early detection of dengue and malaria

    NASA Astrophysics Data System (ADS)

    Rahman, Md Z.; Roytman, Leonid; Kadik, Abdelhamid; Rosy, Dilara A.

    2014-06-01

    Malaria and dengue fever are the two most common mosquito-transmitted diseases, leading to millions of serious illnesses and deaths each year. Because the mosquito vectors are sensitive to environmental conditions such as temperature, precipitation, and humidity, it is possible to map areas currently or imminently at high risk for disease outbreaks using satellite remote sensing. In this paper we propose the development of an operational geospatial system for malaria and dengue fever early warning; this can be done by bringing together geographic information system (GIS) tools, artificial neural networks (ANN) for efficient pattern recognition, the best available ground-based epidemiological and vector ecology data, and current satellite remote sensing capabilities. We use Vegetation Health Indices (VHI) derived from visible and infrared radiances measured by satellite-mounted Advanced Very High Resolution Radiometers (AVHRR) and available weekly at 4-km resolution as one predictor of malaria and dengue fever risk in Bangladesh. As a study area, we focus on Bangladesh where malaria and dengue fever are serious public health threats. The technology developed will, however, be largely portable to other countries in the world and applicable to other disease threats. A malaria and dengue fever early warning system will be a boon to international public health, enabling resources to be focused where they will do the most good for stopping pandemics, and will be an invaluable decision support tool for national security assessment and potential troop deployment in regions susceptible to disease outbreaks.

  2. Airport sentinel surveillance and entry quarantine for dengue infections following a fever screening program in Taiwan

    PubMed Central

    2012-01-01

    Background Dengue has not reached an endemic status in Taiwan; nevertheless, we have implemented a fever screening program at airports for the early detection of febrile passengers with a dengue infection. This study is intended to assess the performance of the airport screening procedures for dengue infection. Methods We analyzed data from the national surveillance system of the Taiwan Centers for Disease Control. We included the imported dengue cases reported by sentinel airports and clinics as well as the domestic cases from 2007–2010. Results Approximately 44.9% (95%CI: 35.73-54.13%) of the confirmed imported dengue cases with an apparent symptom (febrile) in the viremic stage were detected via the airport fever screening program, with an estimated positive predictive value of 2.36% (95% CI: 0.96- 3.75%) and a negative predictive value?>?99.99%. Fluctuations in the number of the symptomatic imported dengue cases identified in the airports (X) were associated with the total number of imported dengue cases (Y) based on a regression analysis of a biweekly surveillance (i.e., n?=?104, R2X:Y?=?0.61, P?dengue cases (X) with a 1–2?month lead time (t) was in parallel with that of the domestic dengue cases (Y) based on a consecutive 4-year surveillance (i.e., n?=?48, R2X(t-1):Y?=?0.22, R2X(t-2):Y?=?0.31, P?dengue at the airports examined in this study indicated some limitations of the fever screening program for the prevention of importation. The screening program could assist in the rapid triage for self-quarantine of some symptomatic dengue cases that were in the viremic stage at the borders and contribute to active sentinel surveillance; however, the blocking of viral transmission to susceptible populations (neighbors or family) from all of the viremic travelers, including those with or without symptoms, is critical to prevent dengue epidemics. Therefore, the reinforcement of mosquito bite prevention and household vector control in dengue-endemic or dengue-competent hotspots during an epidemic season is essential and highly recommended. PMID:22867003

  3. Regional Differences in the Growing Incidence of Dengue Fever in Vietnam Explained by Weather Variability

    PubMed Central

    Vu, Ha Hai; Okumura, Junko; Hashizume, Masahiro; Tran, Duong Nhu; Yamamoto, Taro

    2014-01-01

    Dengue fever is a major health problem in Vietnam, but its incidence differs from province to province. To understand this at the local level, we assessed the effect of four weather components (humidity, rainfall, temperature and sunshine) on the number of dengue cases in nine provinces of Vietnam. Monthly data from 1999 to 2009 were analysed by time-series regression using negative binomial models. A test for heterogeneity was applied to assess the weather-dengue association in the provinces. Those associations were significantly heterogeneous (for temperature, humidity, and sunshine: P < 0.001 heterogeneity test; for rainfall: P = 0.018 heterogeneity test). This confirms that weather components strongly affect dengue transmission at a lag time of 0 to 3 months, with considerable variation in their influence among different areas in Vietnam. This finding may promote the strategic prevention of dengue disease by suggesting specific plans at the local level, rather than a nationally unified approach. PMID:24808744

  4. Self-organized critical phenomenon as a q-exponential decay - Avalanche epidemiology of dengue

    NASA Astrophysics Data System (ADS)

    Saba, H.; Miranda, J. G. V.; Moret, M. A.

    2014-11-01

    We studied the evolution of dengue disease in the state of Bahia. The number of epidemiological dengue cases for each city follows a Self-Organized Criticality behavior (SOC). However, the analysis of the number of cases in Bahia exhibits a q-exponential distribution. To understand this different behavior, we analyzed the distribution of the power law of SOC (?) to all cities of Bahia. Our findings show that the distribution of ? exhibits a dependence between the exponents, which may be because of migration between cities, causing the emergence of outbreaks in different cities in a correlated and asynchronous time series.

  5. Increasing notifications of dengue in Australia related to overseas travel, 1991 to 2012.

    PubMed

    Knope, Katrina; Giele, Carolein

    2013-03-01

    Dengue is an important cause of illness in travellers returning to Australia. The risk of local transmission from imported cases is of particular concern, with several large and explosive outbreaks recorded in recent years in north Queensland in areas where the mosquito vector of dengue is present. The number and proportion of dengue cases that are overseas-acquired is increasing. The number of overseas cases in 2010 and 2011 had increased by 298% and 155% respectively compared with the 5 year mean. The number of overseas acquired cases in 2012 is likely to be the largest on record, with an average of 144 cases per month during the first 7 months of the year. More than half of all dengue cases with a known country of acquisition between 1999 and July 2012 were acquired in Indonesia. In Western Australia in 2010 and 2011, more than 80% of cases acquired in Indonesia were acquired in Bali and the trend has continued into 2012.1 While the frequency of travel by Australians to Indonesia has steadily increased since 2000, this does not completely explain the increased number of dengue cases in returning travellers. The relative risk of dengue in travellers returning from Indonesia between 2000 and 2011 compared with all other destinations was 8.3 (95% confidence interval 7.9-8.9). PMID:23692160

  6. Dengue Fever Occurrence and Vector Detection by Larval Survey, Ovitrap and MosquiTRAP: A Space-Time Clusters Analysis

    PubMed Central

    de Melo, Diogo Portella Ornelas; Scherrer, Luciano Rios; Eiras, Álvaro Eduardo

    2012-01-01

    The use of vector surveillance tools for preventing dengue disease requires fine assessment of risk, in order to improve vector control activities. Nevertheless, the thresholds between vector detection and dengue fever occurrence are currently not well established. In Belo Horizonte (Minas Gerais, Brazil), dengue has been endemic for several years. From January 2007 to June 2008, the dengue vector Aedes (Stegomyia) aegypti was monitored by ovitrap, the sticky-trap MosquiTRAP™ and larval surveys in an study area in Belo Horizonte. Using a space-time scan for clusters detection implemented in SaTScan software, the vector presence recorded by the different monitoring methods was evaluated. Clusters of vectors and dengue fever were detected. It was verified that ovitrap and MosquiTRAP vector detection methods predicted dengue occurrence better than larval survey, both spatially and temporally. MosquiTRAP and ovitrap presented similar results of space-time intersections to dengue fever clusters. Nevertheless ovitrap clusters presented longer duration periods than MosquiTRAP ones, less acuratelly signalizing the dengue risk areas, since the detection of vector clusters during most of the study period was not necessarily correlated to dengue fever occurrence. It was verified that ovitrap clusters occurred more than 200 days (values ranged from 97.0±35.35 to 283.0±168.4 days) before dengue fever clusters, whereas MosquiTRAP clusters preceded dengue fever clusters by approximately 80 days (values ranged from 65.5±58.7 to 94.0±14. 3 days), the former showing to be more temporally precise. Thus, in the present cluster analysis study MosquiTRAP presented superior results for signaling dengue transmission risks both geographically and temporally. Since early detection is crucial for planning and deploying effective preventions, MosquiTRAP showed to be a reliable tool and this method provides groundwork for the development of even more precise tools. PMID:22848729

  7. Comparisons of microbiological evaluations of selected kitchen areas with visual inspections for preventing potential risk of foodborne outbreaks in food service operations.

    PubMed

    Kassa, H; Harrington, B; Bisesi, M; Khuder, S

    2001-04-01

    Most local health departments utilize visual, but not microbiological, methods when inspecting food service operations. To evaluate the marginal utility of microbial testing for minimizing potential risks of foodborne outbreaks in restaurants, swab samples were taken from handwashing sink faucets, freshly cleaned and sanitized food-contact surfaces, and from cooler or freezer door handles in 70 of 350 category-three (high-risk) food service operations in Toledo, Ohio. The swabs were inoculated onto different selective media, and standard procedures were used to identify pathogenic and nonpathogenic bacteria. Microbiological evaluations of the sampled food service operations were compared with visual inspection reports, using a numeric rating scale. Enteric bacteria (that may indicate fecal contamination) were found on food contact surfaces, on cooler or freezer door handles, and on handwashing sink faucets in 86, 57, and 53% of the food service operations, respectively. Approximately 27, 40, and 33% of the restaurants received visual ratings of very poor to poor, fair, and good to very good, respectively. In comparison, 10, 17, and 73% of the restaurants received microbiological rating scores of very poor to poor, fair, and good to very good, respectively. Restaurants with trained personnel received significantly higher visual rating scores than restaurants without trained personnel (P < 0.01). Although more restaurants received poor rating scores by visual inspection than by microbiological evaluation, the presence of fecal bacteria from different sites in more than 50% of the food service operations indicated that visual inspection alone might not be sufficient for minimizing potential risk for foodborne disease outbreaks. Therefore, we recommend periodic microbiological evaluation of high-risk food service operations, in addition to visual inspection, for minimizing the risk of foodborne disease outbreaks. PMID:11307888

  8. Overview of current situation of dengue and dengue vector control

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dengue is the most important arbovirus of humans in the world. It is caused by one of four closely related virus serotypes whose primary vector is Aedes aegypti and secondarily by Ae. albopictus. A global dengue pandemic began in Southeast Asia after World War II and has intensified during the las...

  9. Acute transverse myelitis following dengue virus infection

    Microsoft Academic Search

    Raymond C. S. Seet; Erle C. H. Lim; Einar P. V. Wilder-Smith

    2006-01-01

    The spinal cord is infrequently affected following dengue virus infection. We report a case of transverse myelitis that developed 2 weeks after acute dengue infection and review the literature to elucidate the pathogenesis of spinal cord involvement in dengue infection. We postulate that temporal factors may play a role in the different clinical manifestations, i.e. that acute parainfectious dengue infection

  10. Dengue: update on epidemiology.

    PubMed

    Wilson, Mary Elizabeth; Chen, Lin H

    2015-01-01

    The epidemiology of dengue fever has undergone major shifts in recent decades. The global distribution has expanded to include more geographic areas. The intensity of transmission and the severity of infections have increased in areas where infection was already endemic. Multiple studies provide a clearer picture of the epidemiology and allow mapping of its distribution and change over time. Despite major efforts to control transmission, competent vectors now infest most tropical and subtropical regions; Aedes albopictus, also a competent vector, is able to survive in temperate areas, placing parts of Europe and North America at risk for local transmission. Many research teams in dengue-endemic areas are working to identify key local weather, vector, and other variables that would allow prediction of a likely epidemic early enough to permit interventions to avert it or blunt its impact. PMID:25475383

  11. Synchrony of Sylvatic Dengue Isolations: A Multi-Host, Multi-Vector SIR Model of Dengue Virus Transmission in Senegal

    PubMed Central

    Althouse, Benjamin M.; Lessler, Justin; Sall, Amadou A.; Diallo, Mawlouth; Hanley, Kathryn A.; Watts, Douglas M.; Weaver, Scott C.; Cummings, Derek A. T.

    2012-01-01

    Isolations of sylvatic dengue-2 virus from mosquitoes, humans and non-human primates in Senegal show synchronized multi-annual dynamics over the past 50 years. Host demography has been shown to directly affect the period between epidemics in other pathogen systems, therefore, one might expect unsynchronized multi-annual cycles occurring in hosts with dramatically different birth rates and life spans. However, in Senegal, we observe a single synchronized eight-year cycle across all vector species, suggesting synchronized dynamics in all vertebrate hosts. In the current study, we aim to explore two specific hypotheses: 1) primates with different demographics will experience outbreaks of dengue at different periodicities when observed as isolated systems, and that coupling of these subsystems through mosquito biting will act to synchronize incidence; and 2) the eight-year periodicity of isolations observed across multiple primate species is the result of long-term cycling in population immunity in the host populations. To test these hypotheses, we develop a multi-host, multi-vector Susceptible, Infected, Removed (SIR) model to explore the effects of coupling multiple host-vector systems of dengue virus transmission through cross-species biting rates. We find that under small amounts of coupling, incidence in the host species synchronize. Long-period multi-annual dynamics are observed only when prevalence in troughs reaches vanishingly small levels (), suggesting that these dynamics are inconsistent with sustained transmission in this setting, but are consistent with local dengue virus extinctions followed by reintroductions. Inclusion of a constant introduction of infectious individuals into the system causes the multi-annual periods to shrink, while the effects of coupling remain the same. Inclusion of a stochastic rate of introduction allows for multi-annual periods at a cost of reduced synchrony. Thus, we conclude that the eight-year period separating amplifications of dengue may be explained by cycling in immunity with stochastic introductions. PMID:23209867

  12. The AFHSC-Division of GEIS Operations Predictive Surveillance Program: a multidisciplinary approach for the early detection and response to disease outbreaks

    PubMed Central

    2011-01-01

    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

  13. Hepatitis in Dengue Shock Syndrome

    Microsoft Academic Search

    Luiz José de Souza; Helder Gonçalves Carneiro; João Tadeu Damian Souto Filho; Thiago Ferreira de Souza; Vitor Azevedo Côrtes; Carlos Gicovate Neto; Diogo Assed Bastos; Edno Wallace da Silva Siqueira

    2002-01-01

    Dengue fever is the most frequent arbovirus disease in the world and the most important one in terms of morbidity and mortality. Atypical manifestations of dengue have become commonplace during the last few years, including hepatic damage, which manifests mainly by pain in the right hypochondrium and an increase in the levels of aminotransferases. We describe a case of acute

  14. Space-time analysis of hospitalized dengue patients in rural Thailand reveals important temporal intervals in the pattern of dengue virus transmission

    PubMed Central

    Aldstadt, Jared; Yoon, In-Kyu; Tannitisupawong, Darunee; Jarman, Richard G.; Thomas, Stephen J.; Gibbons, Robert V.; Uppapong, Angkana; Iamsirithaworn, Sopon; Rothman, Alan L.; Scott, Thomas W.; Endy, Timothy

    2014-01-01

    Objective This study uses space-time analysis to determine the temporal intervals at which spatial clustering of dengue hospitalizations occurs. Methods Analysis of 262 people hospitalized and serologically confirmed with dengue virus infections in Kamphaeng Phet, Thailand was performed. The cases were observed between January 1, 2009 and May 6, 2011. Spatial coordinates of each patient’s home were captured using the Global Positioning System. A novel methodology based on the Knox test was used to determine the temporal intervals between cases at which spatial clustering occured. These intervals are indicative of the length of time between successive illnesses in the chain of dengue virus transmission. Results The strongest spatial clustering occurred at the 15–17 day interval. Therewas also significant spatial clustering over short time intervals (2–5 days). The highest excess risk was observed within 200m of a previous hospitalized case and significantly elevated risk persisted within this distance for as long as 32–34 days. Conclusions The analyses indicate that 15–17 days is the most likely serial interval between successive dengue illnesses. This novel methodology relies only on passively-detected, hospitalized case data with household locations and provides a useful tool for understanding region-specific and outbreak-specific dengue virus transmission dynamics. PMID:22808917

  15. Monoclonal antibody to dengue capsid protein

    PubMed Central

    Vazquez, Y; Vazquez, S V; Capó; Torres, G; Caballero, Y; Sánchez, A; Limonta, D; Alvarez, M; Guzmán, MG

    2009-01-01

    Dengue fever (DF) and dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS) are considered the most important arthropod-borne viral diseases in terms of morbidity and mortality. The emergency and severity of dengue (Den) infections increase the necessity of an early, quick and effective dengue laboratory diagnostic. Viral isolation is considered a gold standard for diagnosis of dengue infection using monoclonal antibodies (mAbs) as a tool for determining serotype specificity. Alternatives have been used to improve sensitivity and time to dengue diagnosis. Based on the early expression of dengue C protein in the life cycle, we focused our study on the application of an anti-dengue 2 virus capsid protein mAb in dengue diagnosis. The kinetic expression of dengue-2 capsid in mosquito cells and its immuno-localization in experimentally infected suckling albin Swiss (OF-1) mice brain tissues was established. The results demonstrate the possible utility of this mAb in early dengue diagnosis versus traditional isolation. In addition, a preliminary study of an enzyme immunoassay method using 8H8 mAb for specific detection of dengue C protein antigen was performed, making possible recombinant C protein quantification. The results suggest that detection of dengue capsid protein could be useful in the diagnosis of early dengue infection. PMID:20061827

  16. Seroprevalence of Dengue Fever in US Army Special Operations Forces: Initial Results and the Way Ahead.

    PubMed

    Caci, Jennifer B; Blaylock, Jason M; De La Barrera, Rafael; Griggs, April N; Lin, Leyi; Jarman, Richard G; Thomas, Stephen J; Lyons, Arthur G

    2014-01-01

    The endemicity of dengue fever (DF) and, consequently, sequelae of DF are increasing worldwide. The increases are largely a result of widespread international travel and the increased range of the mosquito vectors. US Army Special Operations Command (USASOC) personnel are at an increased risk of exposure to dengue based on their frequent deployments to and presence in dengue endemic areas worldwide. Repeated deployments to different endemic areas can increase the risk for developing the more serious sequelae of dengue: dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS). Information about the seroprevalence rate of dengue in USASOC personnel, in particular, is lacking and is critical to assessing the risk, tailoring preventive medicine countermeasures, leveraging field diagnostics, and maintaining mission capability. In the first part of a two-part project to assess baseline seroprevalence in USASOC units, a random, unit-stratified sample of 500 anonymous serum specimens from personnel assigned to the highest-risk units in USASOC were screened for dengue using a microneutralization assay. Of the 500 specimens screened, 56 (11.2%) of 500 had neutralizing titers (NT) (MN?? ? 10) against at least one DENV serotype. Subsequent sample titration resulted in 48 (85.7%) of 56 of the samples with NT (MN?? ? 10) against at least one dengue serotype for an overall dengue exposure rate of 9.6% (48 of 500). The second part of the ongoing project, started in 2012, was a multicenter, serosurveillance project using predeployment and postdeployment sera collected from USASOC personnel deployed to South and Central America, Africa, and Southeast Asia. Preliminary results show a 13.2% (55 of 414) seropositivity rate. The significance of these findings as they relate to personal risk and operational impact is discussed. PMID:25344719

  17. Modeling cholera outbreaks

    PubMed Central

    Longini, Ira M.; Morris, J. Glenn

    2014-01-01

    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

  18. Peninsular Florida Tornado Outbreaks

    Microsoft Academic Search

    Bartlett C. Hagemeyer

    1997-01-01

    An analysis of statistics for 1448 tornadoes documented by the National Severe Storms Forecast Center from 1950 through 1994 at, or south of, 308 latitude in Florida was completed to determine the definition of a peninsular Florida tornado outbreak and develop a tornado outbreak climatology. A peninsular Florida tornado outbreak was defined as the occurrence of four or more tornadoes

  19. An adjuvanted, tetravalent dengue virus purified inactivated vaccine candidate induces long-lasting and protective antibody responses against dengue challenge in rhesus macaques.

    PubMed

    Fernandez, Stefan; Thomas, Stephen J; De La Barrera, Rafael; Im-Erbsin, Rawiwan; Jarman, Richard G; Baras, Benoît; Toussaint, Jean-François; Mossman, Sally; Innis, Bruce L; Schmidt, Alexander; Malice, Marie-Pierre; Festraets, Pascale; Warter, Lucile; Putnak, J Robert; Eckels, Kenneth H

    2015-04-01

    The immunogenicity and protective efficacy of a candidate tetravalent dengue virus purified inactivated vaccine (TDENV PIV) formulated with alum or an Adjuvant System (AS01, AS03 tested at three different dose levels, or AS04) was evaluated in a 0, 1-month vaccination schedule in rhesus macaques. One month after dose 2, all adjuvanted formulations elicited robust and persisting neutralizing antibody titers against all four dengue virus serotypes. Most of the formulations tested prevented viremia after challenge, with the dengue serotype 1 and 2 virus strains administered at 40 and 32 weeks post-dose 2, respectively. This study shows that inactivated dengue vaccines, when formulated with alum or an Adjuvant System, are candidates for further development. PMID:25646261

  20. An Adjuvanted, Tetravalent Dengue Virus Purified Inactivated Vaccine Candidate Induces Long-Lasting and Protective Antibody Responses Against Dengue Challenge in Rhesus Macaques

    PubMed Central

    Fernandez, Stefan; Thomas, Stephen J.; De La Barrera, Rafael; Im-erbsin, Rawiwan; Jarman, Richard G.; Baras, Benoît; Toussaint, Jean-François; Mossman, Sally; Innis, Bruce L.; Schmidt, Alexander; Malice, Marie-Pierre; Festraets, Pascale; Warter, Lucile; Putnak, J. Robert; Eckels, Kenneth H.

    2015-01-01

    The immunogenicity and protective efficacy of a candidate tetravalent dengue virus purified inactivated vaccine (TDENV PIV) formulated with alum or an Adjuvant System (AS01, AS03 tested at three different dose levels, or AS04) was evaluated in a 0, 1-month vaccination schedule in rhesus macaques. One month after dose 2, all adjuvanted formulations elicited robust and persisting neutralizing antibody titers against all four dengue virus serotypes. Most of the formulations tested prevented viremia after challenge, with the dengue serotype 1 and 2 virus strains administered at 40 and 32 weeks post-dose 2, respectively. This study shows that inactivated dengue vaccines, when formulated with alum or an Adjuvant System, are candidates for further development. PMID:25646261

  1. An online spatiotemporal prediction model for dengue fever epidemic in Kaohsiung (Taiwan).

    PubMed

    Yu, Hwa-Lung; Angulo, José M; Cheng, Ming-Hung; Wu, Jiaping; Christakos, George

    2014-05-01

    The emergence and re-emergence of disease epidemics is a complex question that may be influenced by diverse factors, including the space-time dynamics of human populations, environmental conditions, and associated uncertainties. This study proposes a stochastic framework to integrate space-time dynamics in the form of a Susceptible-Infected-Recovered (SIR) model, together with uncertain disease observations, into a Bayesian maximum entropy (BME) framework. The resulting model (BME-SIR) can be used to predict space-time disease spread. Specifically, it was applied to obtain a space-time prediction of the dengue fever (DF) epidemic that took place in Kaohsiung City (Taiwan) during 2002. In implementing the model, the SIR parameters were continually updated and information on new cases of infection was incorporated. The results obtained show that the proposed model is rigorous to user-specified initial values of unknown model parameters, that is, transmission and recovery rates. In general, this model provides a good characterization of the spatial diffusion of the DF epidemic, especially in the city districts proximal to the location of the outbreak. Prediction performance may be affected by various factors, such as virus serotypes and human intervention, which can change the space-time dynamics of disease diffusion. The proposed BME-SIR disease prediction model can provide government agencies with a valuable reference for the timely identification, control, and prevention of DF spread in space and time. PMID:24615833

  2. Surveillance of Dengue Fever Virus: A Review of Epidemiological Models and Early Warning Systems

    PubMed Central

    Racloz, Vanessa; Ramsey, Rebecca; Tong, Shilu; Hu, Wenbiao

    2012-01-01

    Dengue fever affects over a 100 million people annually hence is one of the world's most important vector-borne diseases. The transmission area of this disease continues to expand due to many direct and indirect factors linked to urban sprawl, increased travel and global warming. Current preventative measures include mosquito control programs, yet due to the complex nature of the disease and the increased importation risk along with the lack of efficient prophylactic measures, successful disease control and elimination is not realistic in the foreseeable future. Epidemiological models attempt to predict future outbreaks using information on the risk factors of the disease. Through a systematic literature review, this paper aims at analyzing the different modeling methods and their outputs in terms of acting as an early warning system. We found that many previous studies have not sufficiently accounted for the spatio-temporal features of the disease in the modeling process. Yet with advances in technology, the ability to incorporate such information as well as the socio-environmental aspect allowed for its use as an early warning system, albeit limited geographically to a local scale. PMID:22629476

  3. Recent Epidemiological Trends of Dengue in the French Territories of the Americas (2000–2012): A Systematic Literature Review

    PubMed Central

    L'Azou, Maïna; Taurel, Anne-Frieda; Flamand, Claude; Quénel, Philippe

    2014-01-01

    Dengue is a public health concern across the globe, and an escalating problem in the Americas. As part of a wider programme (covering Latin America and South East Asia) to characterize the epidemiology of dengue in dengue endemic areas, we undertook a systematic literature review to assess epidemiological trends (incidence, timing and duration of outbreaks/epidemics, age and sex distribution, serotype distribution, seroprevalence and disease severity) for dengue across the French Territories of the Americas (FTA), in French Guiana, Guadeloupe, Martinique, Saint Martin and Saint Barthélemy between 2000 and 2012 (CRD42012002341: http://www.crd.york.ac.uk/prospero/display_record.asp?ID=CRD42012002341). Of 413 relevant data sources identified, 45 were eligible for inclusion. A large proportion of the available data were from national surveillance reports, and 12 publications were from peer-reviewed journals. During the review period, 3–5 epidemics were identified in each of the island territories and French Guiana, and epidemics were often associated with a shift in the predominant circulating dengue virus serotype. Substantial gaps in epidemiological knowledge were identified. In particular, information regarding dengue virus genotype distribution, seroprevalence and age distribution of dengue were lacking. Additionally, much of the available data were from epidemic years; data from inter-epidemic periods were sparse. Nevertheless, the available epidemiological data showed that dengue is endemic across the FTA and suggest an evolution towards hyperendemicity, highlighting the need to continue the efforts with the existing surveillance programmes to assist in planning an effective vaccination programme once a dengue vaccine is deployed. Protocol registration PROSPERO CRD42012002341 PMID:25375627

  4. Weather factors influencing the occurrence of dengue fever in Nakhon Si Thammarat, Thailand.

    PubMed

    Wongkoon, S; Jaroensutasinee, M; Jaroensutasinee, K

    2013-12-01

    This study explored the impact of weather variability on the transmission of dengue fever in Nakhon Si Thammarat, Thailand. Data on monthly-notified cases of dengue fever, over the period of January 1981 - June 2012 were collected from the Bureau of Epidemiology, Department of Disease Control, Ministry of Public Health. Weather data over the same period were obtained from the Thai Meteorological Department. Spearman correlation analysis and time-series adjusted Poisson regression analysis were performed to quantify the relationship between weather and the number of dengue cases. The results showed that maximum and minimum temperatures at a lag of zero months, the amount of rainfall, and relative humidity at a lag of two months were significant predictors of dengue incidence in Nakhon Si Thammarat. The time series Poisson regression model demonstrated goodness-of-fit with a correlation between observed and predicted number of dengue incidence rate of 91.82%. This model could be used to optimise dengue prevention by predicting trends in dengue incidence. Accurate predictions, for even a few months, provide an invaluable opportunity to mount a vector control intervention or to prepare for hospital demand in the community. PMID:24522133

  5. Comparing dengue and chikungunya emergence and endemic transmission in A. aegypti and A. albopictus.

    PubMed

    Manore, Carrie A; Hickmann, Kyle S; Xu, Sen; Wearing, Helen J; Hyman, James M

    2014-09-01

    Chikungunya and dengue are re-emerging mosquito-borne infectious diseases that are of increasing concern as human travel and expanding mosquito ranges increase the risk of spread. We seek to understand the differences in transient and endemic behavior of chikungunya and dengue; risk of emergence for different virus-vector assemblages; and the role that virus evolution plays in disease dynamics and risk. To address these questions, we adapt a mathematical mosquito-borne disease model to chikungunya and dengue in Aedes aegypti and Aedes albopictus mosquitoes. We derive analytical threshold conditions and important dimensionless parameters for virus transmission; perform sensitivity analysis on quantities of interest such as the basic reproduction number, endemic equilibrium, and first epidemic peak; and compute distributions for the quantities of interest across parameter ranges. We found that chikungunya and dengue exhibit different transient dynamics and long-term endemic levels. While the order of most sensitive parameters is preserved across vector-virus combinations, the magnitude of sensitivity is different across scenarios, indicating that risk of invasion or an outbreak can change with vector-virus assemblages. We found that the dengue - A. aegypti and new Rèunion strain of chikungunya - A. albopictus systems represent the highest risk across the range of parameters considered. These results inform future experimental and field research efforts and point toward effective mitigation strategies adapted to each disease. PMID:24801860

  6. Molecular Characterization and Phylogenetic Analysis of Dengue Viruses Imported into Taiwan during 2008–2010

    PubMed Central

    Huang, Jyh-Hsiung; Su, Chien-Ling; Yang, Cheng-Fen; Liao, Tsai-Ling; Hsu, Tung-Chien; Chang, Shu-Fen; Lin, Chien-Chou; Shu, Pei-Yun

    2012-01-01

    We present our surveillance results on imported dengue cases in Taiwan during 2008–2010. A total of 734 imported dengue patients were identified. The travelers were arriving from 18 countries, including Southeast Asia, the Indian subcontinent, South Pacific islands, and Latin America. Gene sequences from 358 dengue virus (DENV) isolates were used to perform phylogenetic analyses, thus, providing an updated view of the geographic distribution and dynamic transmission of DENV strains circulating in these countries. Our results suggest that the DENV-1 genotype I and DENV-2 Cosmopolitan genotype comprise the predominant DENV strains circulating in Southeast Asian countries. The DENV-3 Genotype III strain was found to be newly emerging in several Southeast Asian countries, however, the Asian genotype 2 and the Asian/American genotype of DENV-2 strains appeared to be less prevalent in Southeast Asia. Furthermore, imported dengue viruses are representative of the overall patterns of serotype/genotype frequencies of dengue outbreaks that occurred in Taiwan. PMID:22855770

  7. Viral Immune Evasion in Dengue: Toward Evidence-Based Revisions of Clinical Practice Guidelines

    PubMed Central

    Chiappelli, Francesco; Santos, Silvana Maria Eloi; Caldeira Brant, Xenia Maria; Bakhordarian, Andre; Thames, April D; Maida, Carl A; Du, Angela M; Jan, Allison L; Nahcivan, Melissa; Nguyen, Mia T; Sama, Nateli

    2014-01-01

    Dengue, a leading cause of illness and death in the tropics and subtropics since the 1950?s, is fast spreading in the Western hemisphere. Over 30% of the world?s population is at risk for the mosquitoes that transmit any one of four related Dengue viruses (DENV). Infection induces lifetime protection to a particular serotype, but successive exposure to a different DENV increases the likelihood of severe form of dengue fever (DF), dengue hemorrhagic fever (DHF), or dengue shock syndrome (DSS). Prompt supportive treatment lowers the risk of developing the severe spectrum of Dengue-associated physiopathology. Vaccines are not available, and the most effective protective measure is to prevent mosquito bites. Here, we discuss selected aspects of the syndemic nature of Dengue, including its potential for pathologies of the central nervous system (CNS). We examine the fundamental mechanisms of cell-mediated and humoral immunity to viral infection in general, and the specific implications of these processes in the regulatory control of DENV infection, including DENV evasion from immune surveillance. In line with the emerging model of translational science in health care, which integrates translational research (viz., going from the patient to the bench and back to the patient) and translational effectiveness (viz., integrating and utilizing the best available evidence in clinical settings), we examine novel and timely evidence-based revisions of clinical practice guidelines critical in optimizing the management of DENV infection and Dengue pathologies. We examine the role of tele-medicine and stakeholder engagement in the contemporary model of patient centered, effectiveness-focused and evidence-based health care. Abbreviations BBB - blood-brain barrier, CNS - central nervous system, DAMP - damage-associated molecular patterns, DENV - dengue virus, DF - dengue fever, DHF - dengue hemorrhagic fever, DSS - dengue shock syndrome, DALYs - isability adjusted life years, IFN-g - interferon-gamma, ILX - interleukinX, JAK/STAT - janus kinase (JAK) / Signal transducer and activator of transcription (STAT), LT - Escherichia coli heat-labile enterotoxin formulations deficient in GM1 binding by mutation (LT[G33D]), MCP-1 - monocyte chemotactic protein 1, M-CSF - macrophage colony-stimulating fact, MHC - major histocompatibility complex, MIF - macrophage migration inhibitory factor, [MIP-1]-? / -? - macrophage inflammatory protein-1 alpha and beta, mAb - monoclonal antibody, NS1 - non-structural protein 1 of dengue virus, NK - natural killer cells, PAMP - pathogen-associated molecular patterns, PBMC - peripheral blood mononuclear cells, TBF-b - transforming growth factor-beta, TNF-? - tumor necrosis-alpha, VHFs - virus hemorrhagic fevers, WHO - World Health Organization. PMID:25670874

  8. Modelling the transmission dynamics of dengue in the presence of Wolbachia.

    PubMed

    Ndii, Meksianis Z; Hickson, R I; Allingham, David; Mercer, G N

    2015-04-01

    Use of the bacterium Wolbachia is an innovative new strategy designed to break the cycle of dengue transmission. There are two main mechanisms by which Wolbachia could achieve this: by reducing the level of dengue virus in the mosquito and/or by shortening the host mosquito's lifespan. However, although Wolbachia shortens the lifespan, it also gives a breeding advantage which results in complex population dynamics. This study focuses on the development of a mathematical model to quantify the effect on human dengue cases of introducing Wolbachia into the mosquito population. The model consists of a compartment-based system of first-order differential equations; seasonal forcing in the mosquito population is introduced through the adult mosquito death rate. The analysis focuses on a single dengue outbreak typical of a region with a strong seasonally-varying mosquito population. We found that a significant reduction in human dengue cases can be obtained provided that Wolbachia-carrying mosquitoes persist when competing with mosquitoes without Wolbachia. Furthermore, using the Wolbachia strain WMel reduces the mosquito lifespan by at most 10% and allows them to persist in competition with non-Wolbachia-carrying mosquitoes. Mosquitoes carrying the WMelPop strain, however, are not likely to persist as it reduces the mosquito lifespan by up to 50%. When all other effects of Wolbachia on the mosquito physiology are ignored, cytoplasmic incompatibility alone results in a reduction in the number of human dengue cases. A sensitivity analysis of the parameters in the model shows that the transmission probability, the biting rate and the average adult mosquito death rate are the most important parameters for the outcome of the cumulative proportion of human individuals infected with dengue. PMID:25645184

  9. Dengue fever and dengue haemorrhagic fever in adolescents and adults

    PubMed Central

    Tantawichien, Terapong

    2012-01-01

    Dengue fever (DF) is endemic in tropical and subtropical zones and the prevalence is increasing across South-east Asia, Africa, the Western Pacific and the Americas. In recent years, the spread of unplanned urbanisation, with associated substandard housing, overcrowding and deterioration in water, sewage and waste management systems, has created ideal conditions for increased transmission of the dengue virus in tropical urban centres. While dengue infection has traditionally been considered a paediatric disease, the age distribution of dengue has been rising and more cases have been observed in adolescents and adults. Furthermore, the development of tourism in the tropics has led to an increase in the number of tourists who become infected, most of whom are adults. Symptoms and risk factors for dengue haemorrhagic fever (DHF) and severe dengue differ between children and adults, with co-morbidities and incidence in more elderly patients associated with greater risk of mortality. Treatment options for DF and DHF in adults, as for children, centre round fluid replacement (either orally or intravenously, depending on severity) and antipyretics. Further data are needed on the optimal treatment of adult patients. PMID:22668446

  10. Dengue fever and dengue haemorrhagic fever in adolescents and adults.

    PubMed

    Tantawichien, Terapong

    2012-05-01

    Dengue fever (DF) is endemic in tropical and subtropical zones and the prevalence is increasing across South-east Asia, Africa, the Western Pacific and the Americas. In recent years, the spread of unplanned urbanisation, with associated substandard housing, overcrowding and deterioration in water, sewage and waste management systems, has created ideal conditions for increased transmission of the dengue virus in tropical urban centres. While dengue infection has traditionally been considered a paediatric disease, the age distribution of dengue has been rising and more cases have been observed in adolescents and adults. Furthermore, the development of tourism in the tropics has led to an increase in the number of tourists who become infected, most of whom are adults. Symptoms and risk factors for dengue haemorrhagic fever (DHF) and severe dengue differ between children and adults, with co-morbidities and incidence in more elderly patients associated with greater risk of mortality. Treatment options for DF and DHF in adults, as for children, centre round fluid replacement (either orally or intravenously, depending on severity) and antipyretics. Further data are needed on the optimal treatment of adult patients. PMID:22668446

  11. Knowledge, Attitude and Practice Regarding Dengue Fever among the Healthy Population of Highland and Lowland Communities in Central Nepal

    PubMed Central

    Dhimal, Meghnath; Aryal, Krishna Kumar; Dhimal, Mandira Lamichhane; Gautam, Ishan; Singh, Shanker Pratap; Bhusal, Chop Lal; Kuch, Ulrich

    2014-01-01

    Background Dengue fever (DF) is the most rapidly spreading mosquito-borne viral disease in the world. In this decade it has expanded to new countries and from urban to rural areas. Nepal was regarded DF free until 2004. Since then dengue virus (DENV) has rapidly expanded its range even in mountain regions of Nepal, and major outbreaks occurred in 2006 and 2010. However, no data on the local knowledge, attitude and practice (KAP) of DF in Nepal exist although such information is required for prevention and control measures. Methods We conducted a community based cross-sectional survey in five districts of central Nepal between September 2011 and February 2012. We collected information on the socio-demographic characteristics of the participants and their knowledge, attitude and practice regarding DF using a structured questionnaire. We then statistically compared highland and lowland communities to identify possible causes of observed differences. Principal Findings Out of 589 individuals interviewed, 77% had heard of DF. Only 12% of the sample had good knowledge of DF. Those living in the lowlands were five times more likely to possess good knowledge than highlanders (P<0.001). Despite low knowledge levels, 83% of the people had good attitude and 37% reported good practice. We found a significantly positive correlation among knowledge, attitude and practice (P<0.001). Among the socio-demographic variables, the education level of the participants was an independent predictor of practice level (P<0.05), and education level and interaction between the sex and age group of the participants were independent predictors of attitude level (P<0.05). Conclusion Despite the rapid expansion of DENV in Nepal, the knowledge of people about DF was very low. Therefore, massive awareness programmes are urgently required to protect the health of people from DF and to limit its further spread in this country. PMID:25007284

  12. Effectiveness of Previous Mumps Vaccination During a Summer Camp Outbreak

    Microsoft Academic Search

    Joshua K. Schaffzin; Lynn Pollock; Cynthia Schulte; Kyle Henry; Gustavo Dayan; Perry Smith

    OBJECTIVES. Mumps is a vaccine-preventable disease that may cause outbreaks. In July 2005, an outbreak of mumps occurred during a children's summer camp in upstate New York. An investigation was initiated to describe the cases and evaluate vaccine effectiveness. METHODS. A retrospective cohort study was conducted among 541 children from the United States and abroad who attended a 1- or

  13. Variations in Modeled Dengue Transmission over Puerto Rico Using a Climate Driven Dynamic Model

    NASA Technical Reports Server (NTRS)

    Morin, Cory; Monaghan, Andrew; Crosson, William; Quattrochi, Dale; Luvall, Jeffrey

    2014-01-01

    Dengue fever is a mosquito-borne viral disease reemerging throughout much of the tropical Americas. Dengue virus transmission is explicitly influenced by climate and the environment through its primary vector, Aedes aegypti. Temperature regulates Ae. aegypti development, survival, and replication rates as well as the incubation period of the virus within the mosquito. Precipitation provides water for many of the preferred breeding habitats of the mosquito, including buckets, old tires, and other places water can collect. Because of variations in topography, ocean influences and atmospheric processes, temperature and rainfall patterns vary across Puerto Rico and so do dengue virus transmission rates. Using NASA's TRMM (Tropical Rainfall Measuring Mission) satellite for precipitation input, ground-based observations for temperature input, and laboratory confirmed dengue cases reported by the Centers for Disease Control and Prevention for parameter calibration, we modeled dengue transmission at the county level across Puerto Rico from 2010-2013 using a dynamic dengue transmission model that includes interacting vector ecology and epidemiological components. Employing a Monte Carlo approach, we performed ensembles of several thousands of model simulations for each county in order to resolve the model uncertainty arising from using different combinations of parameter values that are not well known. The top 1% of model simulations that best reproduced the reported dengue case data were then analyzed to determine the most important parameters for dengue virus transmission in each county, as well as the relative influence of climate variability on transmission. These results can be used by public health workers to implement dengue control methods that are targeted for specific locations and climate conditions.

  14. Dot enzyme immunoassay: an alternative diagnostic aid for dengue fever and dengue haemorrhagic fever.

    PubMed Central

    Cardosa, M. J.; Tio, P. H.

    1991-01-01

    A dot enzyme immunoassay (DEIA) for the detection of antibodies to dengue virus was tested for use as a tool in the presumptive diagnosis of dengue fever and dengue haemorrhagic fever. Paired sera from the following groups of patients were tested using the DEIA and the haemagglutination inhibition (HI) test: those with primary dengue fever; those experiencing a second dengue infection; and febrile patients who did not have dengue. The data obtained show that the DEIA can be effectively used at a serum dilution of 1:1000 to confirm presumptive recent dengue in patients with a second dengue infection. However, demonstration of seroconversion proved necessary for patients with primary dengue. At a serum dilution of 1:1000 the DEIA has a specificity of 97.3%. The role of this simple and rapid test in improving the effectivity of programmes for the control of dengue virus infection is discussed. PMID:1786623

  15. Allosteric inhibition of the NS2B-NS3 protease from dengue virus

    PubMed Central

    Yildiz, Muslum; Ghosh, Sumana; Bell, Jeffrey A.; Sherman, Woody; Hardy, Jeanne A.

    2013-01-01

    Dengue virus is the flavivirus that causes dengue fever, dengue hemorrhagic disease, and dengue shock syndrome, which are currently increasing in incidence worldwide. Dengue virus protease (NS2B-NS3pro) is essential for dengue virus infection and is thus a target of therapeutic interest. To date, attention has focused on developing active-site inhibitors of NS2B-NS3pro. The flat and charged nature of the NS2B-NS3pro active site may contribute to difficulties in developing inhibitors and suggests that a strategy of identifying allosteric sites may be useful. We report an approach that allowed us to scan the NS2B-NS3pro surface by cysteine mutagenesis and use cysteine reactive probes to identify regions of the protein that are susceptible to allosteric inhibition. This method identified a new allosteric site utilizing a circumscribed panel of just eight cysteine variants and only five cysteine reactive probes. The allosterically sensitive site is centered at Ala125, between the 120s loop and the 150s loop. The crystal structures of WT and modified NS2B-NS3pro demonstrate that the 120s loop is flexible. Our work suggests that binding at this site prevents a conformational rearrangement of the NS2B region of the protein, which is required for activation. Preventing this movement locks the protein into the open, inactive conformation, suggesting that this site may be useful in the future development of therapeutic allosteric inhibitors. PMID:24164286

  16. Dengue Virus 1 in Buenos Aires from 1999 to 2010: Towards Local Spread

    PubMed Central

    Tittarelli, Estefanía; Mistchenko, Alicia S.

    2014-01-01

    Dengue virus (DENV) is a public health problem representing the most important arthropod-borne viral disease in humans. In Argentina, Northern provinces have reported autochthonous cases since 1997, though these outbreaks have originated in bordering countries, where co-circulation of more than one serotype has been reported. In the last decade, imported dengue cases have been reported in Buenos Aires, the urban area of Argentina with the highest population density. In 2009, a dengue outbreak affected Buenos Aires and, for the first time, local transmission was detected. All cases of this outbreak were caused by DENV-1. In this report, we present the full-length sequences of 27 DENV-1 isolates, corresponding to imported cases of 1999–2000, as well as local and imported cases of the 2009 and 2010 outbreaks. We analyzed their phylogenetic and phylodynamic relationships and their global and local spread. Additionally, we characterized their genomic and phenotypic features. All cases belonged to DENV-1 genotype V. The most recent ancestor for this genotype was dated ?1934, whereas that for the 2009 outbreak was dated ?2007. The mean rates of nucleotide substitution were 4.98E-4 and 8.53E-4 subs./site/yr, respectively. We inferred an introduction from Paraguay in 1999–2000 and mainly from Venezuela during 2009–2010. Overall, the number of synonymous substitutions per synonymous site significantly exceeded the number of non-synonymous substitutions per site and 12 positively selected sites were detected. These analyses could contribute to a better understanding regarding spread and evolution of this pathogen in the Southern Cone of South America. PMID:25343372

  17. Neurological manifestations of dengue virus infection

    Microsoft Academic Search

    U. K. Misra; J. Kalita; U. K. Syam; T. N. Dhole

    2006-01-01

    AimPaucity of studies on neurological manifestations in dengue virus infection prompted this study. We aim to correlate clinical, radiological and neurophysiological changes in dengue patients with neurological manifestations.

  18. Identification of Dengue Fever Cases in Houston, Texas, with Evidence of Autochthonous Transmission Between 2003 and 2005

    PubMed Central

    Rodriguez, Liliana F.; Herrington, Emily; Kharat, Vineetkumar; Vasilakis, Nikolaos; Walker, Christopher; Turner, Cynthia; Khuwaja, Salma; Arafat, Raouf; Weaver, Scott C.; Martinez, Diana; Kilborn, Cindy; Bueno, Rudy; Reyna, Martin

    2013-01-01

    Abstract Houston, Texas, maintains an environment conducive to dengue virus (DENV) emergence; however, surveillance is passive and diagnostic testing is not readily available. To determine if DENV is present in the area, we tested 3768 clinical specimens (2138 cerebrospinal fluid [CSF] and 1630 serum) collected from patients with suspected mosquito-borne viral disease between 2003 and 2005. We identified 47 immunoglobulin M (IgM)-positive dengue cases, including two cases that were positive for viral RNA in serum for dengue serotype 2. The majority of cases did not report any history of travel outside the Houston area prior to symptom onset. The epidemic curve suggests an outbreak occurred in 2003 with continued low-level transmission in 2004 and 2005. Chart abstractions were completed for 42 of the 47 cases; 57% were diagnosed with meningitis and/or encephalitis, and 43% met the case definition for dengue fever. Two of the 47 cases were fatal, including one with illness compatible with dengue shock syndrome. Our results support local transmission of DENV during the study period. These findings heighten the need for dengue surveillance in the southern United States. PMID:24107180

  19. Outbreaks of Enteric Disease Associated with Animal Contact: Not Just a Foodborne Problem Anymore

    Microsoft Academic Search

    Frederick J. Angulo; Nicole Steinmuller; Linda Demma; Jeff B. Bender; Millicent Eidson

    2006-01-01

    In the past 10 years, an increasing number of outbreaks of enteric disease associated with animals in public settings, such as fairs and petting zoos, have been reported. Fifty-five of these outbreaks that occurred in the United States during 1991- 2005 are reviewed in this article. Lessons learned from these outbreaks and recommendations for prevention are also discussed. Physicians should

  20. Genetic Influences on Dengue Virus Infections

    Microsoft Academic Search

    J. F. P. Wagenaar; A. T. A. Mairuhu; E. C. M. van Gorp

    2004-01-01

    Dengue virus infections are an important cause of morbidity and mortality in the tropics, with 100 million people infected annually and an estimated 2.5 billion people at risk. Human infections can be asymptomatic or can manifest as the self-limited febrile dengue fever, or the more severe and life- threatening dengue haemorrhagic fever (DHF). There are several possible reasons why some

  1. Measles (Rubeola) Cases and Outbreaks

    MedlinePLUS

    ... outbreak linked to two Disney theme parks in Orange County, California...  MMWR: 2014 Outbreaks Measles Outbreak ... Family and a Possibly Associated International Traveler — Orange County, Florida, December 2012-January 2013 MMWR . Sep ...

  2. Direct Costs of Dengue Hospitalization in Brazil: Public and Private Health Care Systems and Use of WHO Guidelines

    PubMed Central

    Vieira Machado, Alessandra A.; Estevan, Anderson Oliveira; Sales, Antonio; Brabes, Kelly Cristina da Silva; Croda, Júlio; Negrão, Fábio Juliano

    2014-01-01

    Background Dengue, an arboviral disease, is a public health problem in tropical and subtropical regions worldwide. In Brazil, epidemics have become increasingly important, with increases in the number of hospitalizations and the costs associated with the disease. This study aimed to describe the direct costs of hospitalized dengue cases, the financial impact of admissions and the use of blood products where current protocols for disease management were not followed. Methods and Results To analyze the direct costs of dengue illness and platelet transfusion in Brazil based on the World Health Organization (WHO) guidelines, we conducted a retrospective cross-sectional census study on hospitalized dengue patients in the public and private Brazilian health systems in Dourados City, Mato Grosso do Sul State, Brazil. The analysis involved cases that occurred from January through December during the 2010 outbreak. In total, we examined 8,226 mandatorily reported suspected dengue cases involving 507 hospitalized patients. The final sample comprised 288 laboratory-confirmed dengue patients, who accounted for 56.8% of all hospitalized cases. The overall cost of the hospitalized dengue cases was US $210,084.30, in 2010, which corresponded to 2.5% of the gross domestic product per capita in Dourados that year. In 35.2% of cases, blood products were used in patients who did not meet the blood transfusion criteria. The overall median hospitalization cost was higher (p?=?0.002) in the group that received blood products (US $1,622.40) compared with the group that did not receive blood products (US $550.20). Conclusion The comparative costs between the public and the private health systems show that both the hospitalization of and platelet transfusion in patients who do not meet the WHO and Brazilian dengue guidelines increase the direct costs, but not the quality, of health care. PMID:25188295

  3. An outbreak of psittacosis.

    PubMed

    Morrison, W M; Hutchison, R B; Thomason, J; Harrington, J H; Herd, G W

    1991-01-01

    An outbreak of chlamydia infection affecting seven people from a small town in Grampian is described. The origin of the outbreak seemed to be a local pet shop. The difficulties of diagnosis and tracing the connections with the pet shop are discussed. The clinical histories of the seven patients are described including those of the two who died. PMID:2002234

  4. Epidemic of dengue-4 virus in Yap State, Federated States of Micronesia, and implication of Aedes hensilli as an epidemic vector.

    PubMed

    Savage, H M; Fritz, C L; Rutstein, D; Yolwa, A; Vorndam, V; Gubler, D J

    1998-04-01

    A dengue fever/dengue hemorrhagic fever (DF/DHF) outbreak in Yap State caused by dengue-4 virus was confirmed serologically and by virus isolation from serum samples collected on each of three island groups. Most DF/DHF cases occurred during a three-month period between mid-May and early August 1995. Five fatal cases, three of which were in children between the ages of four and 11, occurred between June 20 and July 26. A serosurvey conducted in late August revealed anti-dengue IgM prevalence rates of 18% on Yap, 36% on Eauripik, and 6% on Woleai. The majority of residents (93-100%) on the three islands were positive for anti-dengue IgG antibodies, indicating widespread exposure to dengue viruses. The IgG titers indicative of secondary antibody response were noted on Eauripik (6.5%) and Woleai (17%), but were rare on Yap (0.7%). Entomologic investigations implicated the native mosquito species, Aedes hensilli, a member of the Scutellaris Group of Aedes (Stegomyia), as a previously unrecognized epidemic vector of dengue viruses. Aedes hensilli was the most abundant and widespread member of Ae. (Stegomyia) in Yap State, the only species of Ae. (Stegomyia) on Woleai, and the only mosquito species present on Eauripik. New distribution records for mosquito species are reported. PMID:9574802

  5. Economic and Disease Burden of Dengue in Southeast Asia

    PubMed Central

    Shepard, Donald S.; Undurraga, Eduardo A.; Halasa, Yara A.

    2013-01-01

    Background Dengue poses a substantial economic and disease burden in Southeast Asia (SEA). Quantifying this burden is critical to set policy priorities and disease-control strategies. Methods and Findings We estimated the economic and disease burden of dengue in 12 countries in SEA: Bhutan, Brunei, Cambodia, East-Timor, Indonesia, Laos, Malaysia, Myanmar, Philippines, Singapore, Thailand, and Viet Nam. We obtained reported cases from multiple sources—surveillance data, World Health Organization (WHO), and published studies—and adjusted for underreporting using expansion factors from previous literature. We obtained unit costs per episode through a systematic literature review, and completed missing data using linear regressions. We excluded costs such as prevention and vector control, and long-term sequelae of dengue. Over the decade of 2001–2010, we obtained an annual average of 2.9 million (m) dengue episodes and 5,906 deaths. The annual economic burden (with 95% certainty levels) was US$950m (US$610m–US$1,384m) or about US$1.65 (US$1.06–US$2.41) per capita. The annual number of disability-adjusted life years (DALYs), based on the original 1994 definition, was 214,000 (120,000–299,000), which is equivalent to 372 (210–520) DALYs per million inhabitants. Conclusion Dengue poses a substantial economic and disease burden in SEA with a DALY burden per million inhabitants in the region. This burden is higher than that of 17 other conditions, including Japanese encephalitis, upper respiratory infections, and hepatitis B. PMID:23437406

  6. Spatiotemporal Dynamics of Dengue Epidemics, Southern Vietnam

    PubMed Central

    Cuong, Hoang Quoc; Vu, Nguyen Thanh; Cazelles, Bernard; Boni, Maciej F.; Thai, Khoa T.D.; Rabaa, Maia A.; Quang, Luong Chan; Simmons, Cameron P.; Huu, Tran Ngoc

    2013-01-01

    An improved understanding of heterogeneities in dengue virus transmission might provide insights into biological and ecologic drivers and facilitate predictions of the magnitude, timing, and location of future dengue epidemics. To investigate dengue dynamics in urban Ho Chi Minh City and neighboring rural provinces in Vietnam, we analyzed a 10-year monthly time series of dengue surveillance data from southern Vietnam. The per capita incidence of dengue was lower in Ho Chi Minh City than in most rural provinces; annual epidemics occurred 1–3 months later in Ho Chi Minh City than elsewhere. The timing and the magnitude of annual epidemics were significantly more correlated in nearby districts than in remote districts, suggesting that local biological and ecologic drivers operate at a scale of 50–100 km. Dengue incidence during the dry season accounted for 63% of variability in epidemic magnitude. These findings can aid the targeting of vector-control interventions and the planning for dengue vaccine implementation. PMID:23735713

  7. Modulation of inflammation and pathology during dengue virus infection by p38 MAPK inhibitor SB203580.

    PubMed

    Fu, Yilong; Yip, Andy; Seah, Peck Gee; Blasco, Francesca; Shi, Pei-Yong; Hervé, Maxime

    2014-10-01

    Dengue virus (DENV) infection could lead to dengue fever (DF), dengue hemorrhagic fever (DHF) or dengue shock syndrome (DSS). The disease outcome is controlled by both viral and host factors. Inflammation mediators from DENV-infected cells could contribute to increased vascular permeability, leading to severe DHF/DSS. Therefore, suppression of inflammation could be a potential therapeutic approach for treatment of dengue patients. In this context, p38 MAPK (mitogen-activated protein kinase) is a key enzyme that modulates the initiation of stress and inflammatory responses. Here we show that SB203580, a p38 MAPK inhibitor, suppressed the over production of DENV-induced pro-inflammatory mediators such as TNF-?, IL-8, and RANTES from human PBMCs, monocytic THP-1, and granulocyte KU812 cell lines. Oral administration of SB203580 in DENV-infected AG129 mice prevented hematocrit rise and lymphopenia, limited the development of inflammation and pathology (including intestine leakage), and significantly improved survival. These results, for the first time, have provided experimental evidence to imply that a short term inhibition of p38 MAPK may be beneficial to reduce disease symptoms in dengue patients. PMID:25131378

  8. Antiviral actions of flavanoid-derived compounds on dengue virus type-2.

    PubMed

    Muhamad, Mudiana; Kee, Lee Yean; Rahman, Noorsaadah Abd; Yusof, Rohana

    2010-01-01

    Dengue viruses, mosquito-borne members of the Flaviviridae family, are the causative agents of dengue fever and its associated complications, dengue haemorrhagic fever and dengue shock syndrome. To date, more than 2.5 billion people in over 100 countries are at risk of infection, and approximately 20 million infections were reported annually. There is currently no treatment or vaccine available for dengue infection. This study employed a whole-cell organism model or in vitro methods to study the inhibitory property of the flavanoid-derived compounds against DENV2 activity. Results showed that at concentration not exceeding the maximum non-toxic dose (MNTD), these compounds completely prevented DENV2 infection in HepG2 cells as indicated by the absence of cytophatic effects. The in vitro antiviral activity assessed in HepG2 cells employing virus inhibition assay showed high inhibitory activity in a dose dependent manner. At concentration below MNTD, compounds exhibited inhibitory activity against DENV2 with a range of potency strengths of 72% to 100%. The plaque forming unit per ml (pfu/ml) was reduced prominently with a maximum reduction of 98% when the infected HepG2 cells were treated with the highest non-toxic dose of compounds. The highly potent activity of the compounds against DENV2 infection strongly suggests their potential as a lead antiviral agent for dengue. PMID:20567498

  9. High-Throughput Quantitative Proteomic Analysis of Dengue Virus Type 2 Infected A549 Cells

    PubMed Central

    Chiu, Han-Chen; Hannemann, Holger; Heesom, Kate J.; Matthews, David A.; Davidson, Andrew D.

    2014-01-01

    Disease caused by dengue virus is a global health concern with up to 390 million individuals infected annually worldwide. There are no vaccines or antiviral compounds available to either prevent or treat dengue disease which may be fatal. To increase our understanding of the interaction of dengue virus with the host cell, we analyzed changes in the proteome of human A549 cells in response to dengue virus type 2 infection using stable isotope labelling in cell culture (SILAC) in combination with high-throughput mass spectrometry (MS). Mock and infected A549 cells were fractionated into nuclear and cytoplasmic extracts before analysis to identify proteins that redistribute between cellular compartments during infection and reduce the complexity of the analysis. We identified and quantified 3098 and 2115 proteins in the cytoplasmic and nuclear fractions respectively. Proteins that showed a significant alteration in amount during infection were examined using gene enrichment, pathway and network analysis tools. The analyses revealed that dengue virus infection modulated the amounts of proteins involved in the interferon and unfolded protein responses, lipid metabolism and the cell cycle. The SILAC-MS results were validated for a select number of proteins over a time course of infection by Western blotting and immunofluorescence microscopy. Our study demonstrates for the first time the power of SILAC-MS for identifying and quantifying novel changes in cellular protein amounts in response to dengue virus infection. PMID:24671231

  10. GIS-aided planning of insecticide spraying to control dengue transmission

    PubMed Central

    2013-01-01

    Background The purpose of this paper is to integrate a multi-objective integer programming formulation and geographic information system (GIS) into dynamically planning the insecticide spraying area for preventing the transmission of dengue fever. Methods The optimal spraying area to combat dengue infections is calculated by the multi-objective integer programming model using the dengue epidemic in 2007 in Tainan City of southern Taiwan and is compared with the areas actually sprayed by the local health department. The dynamic epidemic indicators (i.e. frequency, intensity and duration) that identify major temporal characteristics of the dynamic process of an epidemic are all incorporated into the model. Results The results indicate that the model can design the spraying area effectively when the trade-off between the coverage of dengue epidemics risk and area compactness is considered. Conclusions The model provides an alternative way to obtain a cost-effective spraying area in controlling future dengue epidemics. The proposed model in this study will be beneficial for strategically allocating dengue control resources. PMID:24066947

  11. Spatio-temporal distribution of dengue fever under scenarios of climate change in the southern Taiwan

    NASA Astrophysics Data System (ADS)

    Lee, Chieh-Han; Yu, Hwa-Lung

    2014-05-01

    Dengue fever has been recognized as the most important widespread vector-borne infectious disease in recent decades. Over 40% of the world's population is risk from dengue and about 50-100 million people are infected world wide annually. Previous studies have found that dengue fever is highly correlated with climate covariates. Thus, the potential effects of global climate change on dengue fever are crucial to epidemic concern, in particular, the transmission of the disease. This present study investigated the nonlinearity of time-delayed impact of climate on spatio-temporal variations of dengue fever in the southern Taiwan during 1998 to 2011. A distributed lag nonlinear model (DLNM) is used to assess the nonlinear lagged effects of meteorology. The statistically significant meteorological factors are considered, including weekly minimum temperature and maximum 24-hour rainfall. The relative risk and the distribution of dengue fever then predict under various climate change scenarios. The result shows that the relative risk is similar for different scenarios. In addition, the impact of rainfall on the incidence risk is higher than temperature. Moreover, the incidence risk is associated to spatially population distribution. The results can be served as practical reference for environmental regulators for the epidemic prevention under climate change scenarios.

  12. Long-Term and Seasonal Dynamics of Dengue in Iquitos, Peru

    PubMed Central

    Stoddard, Steven T.; Wearing, Helen J.; Reiner, Robert C.; Morrison, Amy C.; Astete, Helvio; Vilcarromero, Stalin; Alvarez, Carlos; Ramal-Asayag, Cesar; Sihuincha, Moises; Rocha, Claudio; Halsey, Eric S.; Scott, Thomas W.; Kochel, Tadeusz J.; Forshey, Brett M.

    2014-01-01

    Introduction Long-term disease surveillance data provide a basis for studying drivers of pathogen transmission dynamics. Dengue is a mosquito-borne disease caused by four distinct, but related, viruses (DENV-1-4) that potentially affect over half the world's population. Dengue incidence varies seasonally and on longer time scales, presumably driven by the interaction of climate and host susceptibility. Precise understanding of dengue dynamics is constrained, however, by the relative paucity of laboratory-confirmed longitudinal data. Methods We studied 10 years (2000–2010) of laboratory-confirmed, clinic-based surveillance data collected in Iquitos, Peru. We characterized inter and intra-annual patterns of dengue dynamics on a weekly time scale using wavelet analysis. We explored the relationships of case counts to climatic variables with cross-correlation maps on annual and trimester bases. Findings Transmission was dominated by single serotypes, first DENV-3 (2001–2007) then DENV-4 (2008–2010). After 2003, incidence fluctuated inter-annually with outbreaks usually occurring between October and April. We detected a strong positive autocorrelation in case counts at a lag of ?70 weeks, indicating a shift in the timing of peak incidence year-to-year. All climatic variables showed modest seasonality and correlated weakly with the number of reported dengue cases across a range of time lags. Cases were reduced after citywide insecticide fumigation if conducted early in the transmission season. Conclusions Dengue case counts peaked seasonally despite limited intra-annual variation in climate conditions. Contrary to expectations for this mosquito-borne disease, no climatic variable considered exhibited a strong relationship with transmission. Vector control operations did, however, appear to have a significant impact on transmission some years. Our results indicate that a complicated interplay of factors underlie DENV transmission in contexts such as Iquitos. PMID:25033412

  13. Impact of meteorological factors on the spatiotemporal patterns of dengue fever incidence.

    PubMed

    Chien, Lung-Chang; Yu, Hwa-Lung

    2014-12-01

    Dengue fever is one of the most widespread vector-borne diseases and has caused more than 50 million infections annually over the world. For the purposes of disease prevention and climate change health impact assessment, it is crucial to understand the weather-disease associations for dengue fever. This study investigated the nonlinear delayed impact of meteorological conditions on the spatiotemporal variations of dengue fever in southern Taiwan during 1998-2011. We present a novel integration of a distributed lag nonlinear model and Markov random fields to assess the nonlinear lagged effects of weather variables on temporal dynamics of dengue fever and to account for the geographical heterogeneity. This study identified the most significant meteorological measures to dengue fever variations, i.e., weekly minimum temperature, and the weekly maximum 24-hour rainfall, by obtaining the relative risk (RR) with respect to disease counts and a continuous 20-week lagged time. Results show that RR increased as minimum temperature increased, especially for the lagged period 5-18 weeks, and also suggest that the time to high disease risks can be decreased. Once the occurrence of maximum 24-hour rainfall is >50 mm, an associated increased RR lasted for up to 15 weeks. A temporary one-month decrease in the RR of dengue fever is noted following the extreme rain. In addition, the elevated incidence risk is identified in highly populated areas. Our results highlight the high nonlinearity of temporal lagged effects and magnitudes of temperature and rainfall on dengue fever epidemics. The results can be a practical reference for the early warning of dengue fever. PMID:25084561

  14. Models of dengue virus infection

    PubMed Central

    Bente, Dennis A.; Rico-Hesse, Rebeca

    2007-01-01

    The need for models of dengue disease has reached a pinnacle as the transmission of this mosquito-borne virus has increased dramatically. Little is known about the mechanisms that lead to dengue fever and its more severe form, dengue hemorrhagic fever; this is owing to the fact that only humans show signs of disease. In the past 5 years, research has better identified the initial target cells of infection, and this has led to the development of models of infection in primary human cell cultures. Mouse–human chimeras, containing these target cells, have also led to progress in developing animal models. These advances should soon end the stalemate in testing antivirals and vaccine preparations that had necessarily been done in incomplete or irrelevant models. PMID:18087566

  15. USING DISABILITY-ADJUSTED LIFE YEARS TO ASSESS THE ECONOMIC IMPACT OF DENGUE IN PUERTO RICO: 1984-1994

    Microsoft Academic Search

    MARTIN I. MELTZER; GARY G. CLARK; PAUL REITER; DUANE J. GUBLER

    1998-01-01

    This study presents the disability-adjusted life years (DALYs), a non-monetary economic measure of impact, lost to dengue in Puerto Rico for the period 1984-1994. Data on the number of reported cases, cases with hemorrhagic manifestations, hospitalizations, and deaths were obtained from a surveillance system maintained at the Dengue Branch, Division of Vector-Borne Infectious Diseases, Centers for Disease Control and Prevention

  16. Community Knowledge, Health Beliefs, Practices and Experiences Related to Dengue Fever and Its Association with IgG Seropositivity

    PubMed Central

    Wong, Li Ping; AbuBakar, Sazaly; Chinna, Karuthan

    2014-01-01

    Background Demographic, economic and behavioural factors are central features underpinning the successful management and biological control of dengue. This study aimed to examine these factors and their association with the seroprevalence of this disease. Methodology We conducted a cross-sectional telephone survey of households in a 3 km radius of the schools where we had conducted serological tests on the student population in a previous study. Households were surveyed about their socio-demographics, knowledge, practices, and Health Belief Model (HBM) constructs. The results were then associated with the prevalence rate of dengue in the community, as marked by IgG seropositivity of the students who attended school there. Results A total of 1,400 complete responses were obtained. The community's IgG seropositivity was significantly positively associated with high household monthly income, high-rise residential building type, high surrounding vegetation density, rural locality, high perceived severity and susceptibility, perceived barriers to prevention, knowing that a neighbour has dengue, frequent fogging and a higher level of knowledge about dengue. In the multivariate analyses, three major correlates of the presence of IgG seropositivity in the community: (1) high-rise residential apartment house type or condominium buildings; (2) the main construct of the HBM, perceived severity and susceptibility; and (3) the additional constructs of the HBM, lack of preventive measures from the community level and having a neighbour with dengue as a cue to action. Weak correlations were found between self-practices to prevent dengue and the level of dengue seropositivity in the community, and between HBM constructs and knowledge (r?=?0.09). Conclusions The residential environment factor and the constructs of the HBM are useful and important elements in developing interventions to prevent and control dengue. The study also sheds light on the importance of the need for approaches that ensure the translation of knowledge into practice. PMID:24853259

  17. Dengue fever in returned Swedish travelers from Thailand.

    PubMed

    Tuiskunen, Anne; Hjertqvist, Marika; Vene, Sirkka; Lundkvist, Ake

    2011-01-01

    The dengue viruses (DENV) are endemic in the tropical and sub-tropical countries and cause the most common arthropod-borne viral disease in humans. Travelers visiting endemic areas may both acquire and spread DENV infections, and this is the reason why prevention of mosquito bites is of crucial importance. Dengue fever (DF) has become the most common cause for tropical fever in Swedish tourists. Swedish data from 1995 to 2010 show that the number of DF cases has increased since the beginning of 2000; partly due to improved diagnostics based on IgM detection, and partly due to an increase in the number of tourists traveling to, and between, endemic areas. Young adults aged 20-29 are mostly affected, and epidemiological data indicate increased incidence rates from 2008 onwards. Our data pose a call for attention when traveling to DENV endemic areas as well as an increased awareness among physicians when treating returning travelers. PMID:22957112

  18. Aedes aegypti from temperate regions of South America are highly competent to transmit dengue virus

    PubMed Central

    2013-01-01

    Background Aedes aegypti is extensively spread throughout South America where it has been responsible for large dengue epidemics during the last decades. Intriguingly, dengue transmission has not been reported in Uruguay and is essentially prevalent in subtropical northern Argentina which borders Uruguay. Methods We assessed vector competence for dengue virus (DENV) of Ae. aegypti populations collected in subtropical Argentina (Corrientes) as well as temperate Uruguay (Salto) and Argentina (Buenos Aires) in 2012 using experimental oral infections with DENV-2. Mosquitoes were incubated at 28°C and examined at 14 and 21 days p.i. to access viral dissemination and transmission. Batches of the Buenos Aires mosquitoes were also incubated at 15°C and 20°C. Results Although mosquitoes from temperate Uruguay and Argentina were competent to transmit DENV, those from subtropical Argentina were more susceptible, displaying the highest virus titters in the head and presenting the highest dissemination of infection and transmission efficiency rates when incubated at 28°C. Interestingly, infectious viral particles could be detected in saliva of mosquitoes from Buenos Aires exposed to 15°C and 20°C. Conclusions There is a potential risk of establishing DENV transmission in Uruguay and for the spread of dengue outbreaks to other parts of subtropical and temperate Argentina, notably during spring and summer periods. PMID:24373423

  19. Forecasting fluctuating outbreaks in seasonally driven epidemics

    NASA Astrophysics Data System (ADS)

    Stone, Lewi

    2009-03-01

    Seasonality is a driving force that has major impact on the spatio-temporal dynamics of natural systems and their populations. This is especially true for the transmission of common infectious diseases such as influenza, measles, chickenpox, and pertussis. Here we gain new insights into the nonlinear dynamics of recurrent diseases through the analysis of the classical seasonally forced SIR epidemic model. Despite many efforts over the last decades, it has been difficult to gain general analytical insights because of the complex synchronization effects that can evolve between the external forcing and the model's natural oscillations. The analysis advanced here attempts to make progress in this direction by focusing on the dynamics of ``skips'' where we identify and predict years in which the epidemic is absent rather than outbreak years. Skipping events are intrinsic to the forced SIR model when parameterised in the chaotic regime. In fact, it is difficult if not impossible to locate realistic chaotic parameter regimes in which outbreaks occur regularly each year. This contrasts with the well known Rossler oscillator whose outbreaks recur regularly but whose amplitude vary chaotically in time (Uniform Phase Chaotic Amplitude oscillations). The goal of the present study is to develop a ``language of skips'' that makes it possible to predict under what conditions the next outbreak is likely to occur, and how many ``skips'' might be expected after any given outbreak. We identify a new threshold effect and give clear analytical conditions that allow accurate predictions. Moreover, the time of occurrence (i.e., phase) of an outbreak proves to be a useful new parameter that carries important epidemiological information. In forced systems, seasonal changes can prevent late-initiating outbreaks (i.e., having high phase) from running to completion. These principles yield forecasting tools that should have relevance for the study of newly emerging and reemerging diseases.

  20. Outbreaks of campylobacteriosis in Australia, 2001 to 2006.

    PubMed

    Unicomb, Leanne E; Fullerton, Kathleen E; Kirk, Martyn D; Stafford, Russell J

    2009-12-01

    The objective of this study was to examine the frequency of Campylobacter outbreaks in Australia and determine common transmission routes and vehicles. Summary and unit data on Campylobacter outbreaks that occurred between January 2001 and December 2006 were systematically collected and analyzed. Data from Campylobacter mandatory notifications for the same period were used for comparison. During the study period there were 33 Campylobacter outbreaks reported, affecting 457 persons. Of these, 147 (32%) had laboratory-confirmed infections, constituting 0.1% of notified Campylobacter cases. Campylobacter outbreaks most commonly occurred during the Australian Spring (September to November; n = 14, 45%), when notifications generally peaked. Transmission was predominantly foodborne or suspected foodborne (n = 27, 82%), commercial settings (n = 15, 55%) being most commonly involved. There were eight foodborne outbreaks (30%) attributed to food prepared or eaten at institutions; four (15%) at aged care facilities and three (11%) at school camps. A vehicle or suspected vehicle was determined for 16 (59%) foodborne outbreaks; poultry (chicken or duck) was associated with 11 (41%) of these, unpasteurized milk and salad were associated with two outbreaks each. Three potential waterborne outbreaks were detected, and one was due to person-to-person transmission. Campylobacter outbreaks were more commonly detected during this study period compared to a previous 6-year period (n = 9) when prospective recording of information was not undertaken. However, outbreak cases continue to constitute a very small proportion of notifications. Improved recognition through subtyping is required to enhance outbreak detection and investigation so as to aid policy formulation for prevention of infection. In addition to detection of chicken as a common source of outbreaks, these data highlight the importance of directing policy at commercial premises, aged care facilities, and school camps to reduce Campylobacter disease burden. PMID:19895264

  1. Male–female differences in the number of reported incident dengue fever cases in six Asian countries

    PubMed Central

    Anker, Martha

    2011-01-01

    Introduction Demographic factors, such as age and sex, are associated with the likelihood of exposure to Aedes aegypti, the vector for dengue. However, dengue data disaggregated by both sex and age are not routinely reported or analysed by national surveillance systems. This study analysed the reported number of incident dengue cases by age and sex for six countries in Asia. Methods Data for the Lao People's Democratic Republic, the Philippines, Singapore and Sri Lanka were obtained from DengueNet; the number of male and female dengue cases was available for four age groups (< 1, 1–4, 5–14 and ? 15 years) over a cumulative period of six to 10 years. Data for Cambodia (2010) and Malaysia (1997–2008) were obtained from their respective ministries of health. Results An excess of males was found among reported dengue cases ? 15 years of age. This pattern was observed consistently over several years across six culturally and economically diverse countries. Discussion These data indicated the importance of reporting data stratified by both sex and age since collapsing the data over all ages would have masked some of the male–female differences. To target preventive measures appropriately, assessment of gender by age is important for dengue because biological or gender-related factors can change over the human lifespan and gender-related factors may differ across countries. PMID:23908884

  2. Nation-Wide, Web-Based, Geographic Information System for the Integrated Surveillance and Control of Dengue Fever in Mexico

    PubMed Central

    Hernández-Ávila, Juan Eugenio; Rodríguez, Mario-Henry; Santos-Luna, René; Sánchez-Castañeda, Veronica; Román-Pérez, Susana; Ríos-Salgado, Víctor Hugo; Salas-Sarmiento, Jesús Alberto

    2013-01-01

    Dengue fever incidence and its geographical distribution are increasing throughout the world. Quality and timely information is essential for its prevention and control. A web based, geographically enabled, dengue integral surveillance system (Dengue-GIS) was developed for the nation-wide collection, integration, analysis and reporting of geo-referenced epidemiologic, entomologic, and control interventions data. Consensus in the design and practical operation of the system was a key factor for its acceptance. Working with information systems already implemented as a starting point facilitated its acceptance by officials and operative personnel. Dengue-GIS provides the geographical detail needed to plan, asses and evaluate the impact of control activities. The system is beginning to be adopted as a knowledge base by vector control programs. It is used to generate evidence on impact and cost-effectiveness of control activities, promoting the use of information for decision making at all levels of the vector control program. Dengue-GIS has also been used as a hypothesis generator for the academic community. This GIS-based model system for dengue surveillance and the experience gathered during its development and implementation could be useful in other dengue endemic countries and extended to other infectious or chronic diseases. PMID:23936394

  3. Seroepidemiology of Dengue Virus in Mayotte, Indian Ocean, 2006

    PubMed Central

    Sissoko, Daouda; Ezzedine, Khaled; Giry, Claude; Moendandzé, Amrat; Lernout, Tinne; D'Ortenzio, Eric; Pettinelli, François; Malvy, Denis

    2010-01-01

    Background Although Dengue virus (DENV) circulation had been documented in neighbouring South-western Indian Ocean Islands, its presence in Mayotte is poorly characterised. To address this issue, we aimed to assess the seroprevalence of dengue IgG antibodies (DENV-IgG Ab) among the population and to investigate potential associations with individual and household characteristics. Methods/Principal Findings In November–December 2006 we conducted a cross-sectional serologic survey in Mayotte among 1,154 inhabitants aged ?2 years by using a multistage cluster random sampling method. The overall prevalence of DENV-specific IgG antibodies (ELISA) was 22.73% (95% CI, 18.16–27.31). The age-specific seroprevalence increased with age (?2 for trend?=?11.86, P<0.0006), and was linked with previous known outbreaks in this region. In multivariate analysis, older age, being born in the Comoros and living in a household with a low socioeconomic index were positively associated with DENV IgG antibody positivity. Conclusions These findings document substantial prior exposure of the population of Mayotte to DENV and highlight the risk of severe illness due to the possibility of sequential DENV infections. Further investigations characterizing current DENV circulation patterns and associated serotypes are needed. PMID:21152441

  4. Imported Dengue Cases, Weather Variation and Autochthonous Dengue Incidence in Cairns, Australia

    PubMed Central

    Huang, Xiaodong; Williams, Gail; Clements, Archie C. A.; Hu, Wenbiao

    2013-01-01

    Background Dengue fever (DF) outbreaks often arise from imported DF cases in Cairns, Australia. Few studies have incorporated imported DF cases in the estimation of the relationship between weather variability and incidence of autochthonous DF. The study aimed to examine the impact of weather variability on autochthonous DF infection after accounting for imported DF cases and then to explore the possibility of developing an empirical forecast system. Methodology/principal finds Data on weather variables, notified DF cases (including those acquired locally and overseas), and population size in Cairns were supplied by the Australian Bureau of Meteorology, Queensland Health, and Australian Bureau of Statistics. A time-series negative-binomial hurdle model was used to assess the effects of imported DF cases and weather variability on autochthonous DF incidence. Our results showed that monthly autochthonous DF incidences were significantly associated with monthly imported DF cases (Relative Risk (RR):1.52; 95% confidence interval (CI): 1.01–2.28), monthly minimum temperature (oC) (RR: 2.28; 95% CI: 1.77–2.93), monthly relative humidity (%) (RR: 1.21; 95% CI: 1.06–1.37), monthly rainfall (mm) (RR: 0.50; 95% CI: 0.31–0.81) and monthly standard deviation of daily relative humidity (%) (RR: 1.27; 95% CI: 1.08–1.50). In the zero hurdle component, the occurrence of monthly autochthonous DF cases was significantly associated with monthly minimum temperature (Odds Ratio (OR): 1.64; 95% CI: 1.01–2.67). Conclusions/significance Our research suggested that incidences of monthly autochthonous DF were strongly positively associated with monthly imported DF cases, local minimum temperature and inter-month relative humidity variability in Cairns. Moreover, DF outbreak in Cairns was driven by imported DF cases only under favourable seasons and weather conditions in the study. PMID:24349148

  5. Tetravalent dengue DIIIC protein together with alum and ODN elicits a Th1 response and neutralizing antibodies in mice.

    PubMed

    Zuest, Roland; Valdes, Iris; Skibinski, David; Lin, Yufang; Toh, Ying Xiu; Chan, Katherine; Hermida, Lisset; Connolly, John; Guillen, Gerardo; Fink, Katja

    2015-03-17

    Dengue disease is a global challenge for healthcare systems particularly during outbreaks, and millions of dollars are spent every year for vector control. An efficient and safe vaccine that is cost-effective could resolve the burden that dengue virus imposes on affected countries. We describe here the immunogenicity of a tetravalent formulation of a recombinant fusion protein consisting of E domain III and the capsid protein of dengue serotypes 1-4 (Tetra DIIIC). E domain III is an epitope for efficient neutralizing antibodies while the capsid protein contains T cell epitopes. Besides combining B and T cell epitopes, Tetra DIIIC is highly immunogenic due to its aggregate form and a two-component adjuvant. Following previous studies assessing the monovalent DIIIC formulations, we addressed here the quality and breadth of the T cell- and antibody response of Tetra DIIIC in mice. Tetra DIIIC induced a Th1-type response against all four DENV serotypes and dengue-specific antibodies were predominantly IgG1 and IgG2a and neutralizing, while the induction of neutralizing antibodies was dependent on IFN signaling. Importantly, the Th1 and IgG1/IgG2a profile of the DIIIC vaccine approach is similar to an efficient natural anti-dengue response. PMID:25659270

  6. Evaluation of the WHO classification of dengue disease severity during an epidemic in 2011 in the state of Ceará, Brazil

    PubMed Central

    Cavalcanti, Luciano Pamplona de Góes; Mota, Lia Alves Martins; Lustosa, Gustavo Porto; Fortes, Mayara Carvalho; Mota, Davi Alves Martins; Lima, Antônio Afonso Bezerra; Coelho, Ivo Castelo Branco; Mourão, Maria Paula Gomes

    2013-01-01

    In 2009, the World Health Organization (WHO) issued a new guideline that stratifies dengue-affected patients into severe (SD) and non-severe dengue (NSD) (with or without warning signs). To evaluate the new recommendations, we completed a retrospective cross-sectional study of the dengue haemorrhagic fever (DHF) cases reported during an outbreak in 2011 in northeastern Brazil. We investigated 84 suspected DHF patients, including 45 (53.6%) males and 39 (46.4%) females. The ages of the patients ranged from five-83 years and the median age was 29. According to the DHF/dengue shock syndrome classification, 53 (63.1%) patients were classified as having dengue fever and 31 (36.9%) as having DHF. According to the 2009 WHO classification, 32 (38.1%) patients were grouped as having NSD [4 (4.8%) without warning signs and 28 (33.3%) with warning signs] and 52 (61.9%) as having SD. A better performance of the revised classification in the detection of severe clinical manifestations allows for an improved detection of patients with SD and may reduce deaths. The revised classification will not only facilitate effective screening and patient management, but will also enable the collection of standardised surveillance data for future epidemiological and clinical studies. PMID:24626308

  7. Scientific consultation on cell mediated immunity (CMI) in dengue and dengue vaccine development

    Microsoft Academic Search

    Stephen J. Thomas; Joachim Hombach; Alan Barrett

    2009-01-01

    Dengue is a re-emerging arboviral disease of great public health importance. Limited understanding of protective immune responses against dengue has hampered advancement of dengue vaccine candidates. Demonstrating an immunological correlate of protection has been limited to associating quantitative neutralizing antibody titers with clinical outcomes following infection. There have been a number of studies investigating the role of cell mediated immunity

  8. Management of nosocomial scabies, an outbreak of occupational disease.

    PubMed

    Jungbauer, Frank H W; Veenstra-Kyuchukova, Yanka K; Koeze, Jacqueline; KruijtSpanjer, Martijn R; Kardaun, Sylvia H

    2015-05-01

    Background The optimal approach to managing institutional scabies outbreaks has yet to be defined. We report on outbreak managements are needed. Methods We report on a large outbreak of scabies in three acute care wards in a tertiary university teaching hospital in the Netherlands. Results The outbreak potentially effected 460 patients and 185 health care workers who had been exposed to the index patient. Conclusion Containment of an outbreak relies on a quick and strict implementation of appropriate infection control measures and should include simultaneous treatment of all infested persons and exposed contacts to prevent secondary spread and prolonged post-intervention surveillance. Am. J. Ind. Med. 58:577-582, 2015. © 2015 Wiley Periodicals, Inc. PMID:25777802

  9. A delay differential equation model for dengue transmission with regular visits to a mosquito breeding site

    NASA Astrophysics Data System (ADS)

    Yaacob, Y.; Yeak, S. H.; Lim, R. S.; Soewono, E.

    2015-03-01

    Dengue disease has been known as one of widely transmitted vector-borne diseases which potentially affects millions of people throughout the world especially in tropical and sub-tropical countries. One of the main factors contributing in the complication of the transmission process is the mobility of people in which people may get infection in the places far from their home. Here we construct a delay differential equation model for dengue transmission in a closed population where regular visits of people to a mosquito breeding site out of their residency such as traditional market take place daily. Basic reproductive ratio of the system is obtained and depends on the ratio between the outgoing rates of susceptible human and infective human. It is shown that the increase of mobility with different variation of mobility rates may contribute to different level of basic reproductive ratio as well as different level of outbreaks.

  10. An online spatio-temporal prediction model for dengue fever epidemic in Kaohsiung,Taiwan

    NASA Astrophysics Data System (ADS)

    Cheng, Ming-Hung; Yu, Hwa-Lung; Angulo, Jose; Christakos, George

    2013-04-01

    Dengue Fever (DF) is one of the most serious vector-borne infectious diseases in tropical and subtropical areas. DF epidemics occur in Taiwan annually especially during summer and fall seasons. Kaohsiung city has been one of the major DF hotspots in decades. The emergence and re-emergence of the DF epidemic is complex and can be influenced by various factors including space-time dynamics of human and vector populations and virus serotypes as well as the associated uncertainties. This study integrates a stochastic space-time "Susceptible-Infected-Recovered" model under Bayesian maximum entropy framework (BME-SIR) to perform real-time prediction of disease diffusion across space-time. The proposed model is applied for spatiotemporal prediction of the DF epidemic at Kaohsiung city during 2002 when the historical series of high DF cases was recorded. The online prediction by BME-SIR model updates the parameters of SIR model and infected cases across districts over time. Results show that the proposed model is rigorous to initial guess of unknown model parameters, i.e. transmission and recovery rates, which can depend upon the virus serotypes and various human interventions. This study shows that spatial diffusion can be well characterized by BME-SIR model, especially at the district surrounding the disease outbreak locations. The prediction performance at DF hotspots, i.e. Cianjhen and Sanmin, can be degraded due to the implementation of various disease control strategies during the epidemics. The proposed online disease prediction BME-SIR model can provide the governmental agency with a valuable reference to timely identify, control, and efficiently prevent DF spread across space-time.

  11. Safety and immunogenicity of attenuated dengue virus vaccines (Aventis Pasteur) in human volunteers

    Microsoft Academic Search

    N. Kanesa-thasan; W. Sun; G. Kim-Ahn; S. Van Albert; J. R. Putnak; A. King; B. Raengsakulsrach; H. Christ-Schmidt; K. Gilson; J. M. Zahradnik; D. W. Vaughn; B. L. Innis; J.-F. Saluzzo; C. H. Hoke Jr

    2001-01-01

    A randomized, controlled, double-blinded study was conducted to determine safety and immunogenicity of five live attenuated dengue vaccines produced by Aventis Pasteur (AvP). The study was completed with 40 flavivirus non-immune volunteers: five recipients of each monovalent (dengue-1, dengue-2, dengue-3, or dengue-4) vaccine, ten recipients of tetravalent (dengue-1, dengue-2, dengue-3, and dengue-4) vaccine, and ten recipients of vaccine vehicle alone.

  12. Insecticide Resistance in the Dengue Vector Aedes aegypti from Martinique: Distribution, Mechanisms and

    E-print Network

    Paris-Sud XI, Université de

    Insecticide Resistance in the Dengue Vector Aedes aegypti from Martinique: Distribution, Mechanisms-biting mosquito. The most effective proven method for disease prevention has been by vector control by various chemical or biological means. Unfortunately insecticide resistance has already been observed on the Island

  13. The Utility of a Board Game for Dengue Haemorrhagic Fever Health Education

    ERIC Educational Resources Information Center

    Lennon, Jeffrey L.; Coombs, David W.

    2007-01-01

    Purpose: The purpose of this study is to test the effectiveness of an educational board game for increasing knowledge, positive attitudes-beliefs, and self-efficacy for dengue prevention in a sample of Philippine school children and adolescents. Effective board games are more advantageous than lectures because they are adaptable, inexpensive and…

  14. An unusual ocular emergency in severe dengue.

    PubMed

    Nagaraj, Kalpana Badami; Jayadev, Chaitra; Yajmaan, Soumya; Prakash, Savitha

    2014-01-01

    Dengue, one of the most common mosquito-borne flavivirus diseases affecting humans, is spread by the Aedes aegypti mosquito. Most people infected with dengue virus are asymptomatic or only have mild symptoms such as an uncomplicated fever; few have more severe features, while in a small proportion it is life-threatening. Severe dengue is defined as that associated with severe bleeding, severe organ dysfunction, or severe plasma leakage. Ophthalmic manifestations can involve both the anterior and posterior segment. We report an ocular emergency of proptosis and globe rupture in a patient with severe dengue. PMID:25371643

  15. Chloroquine use improves dengue-related symptoms

    PubMed Central

    Borges, Marcos Carvalho; Castro, Luiza Antunes; da Fonseca, Benedito Antonio Lopes

    2013-01-01

    Dengue is the most important arboviral disease in the world. As chloroquine, an antimalarial agent, has shown some antiviral effects, this study evaluated its effect in patients with dengue. A randomised, double-blind study was performed by administering chloroquine or placebo for three days to 129 patients with dengue-related symptoms. Of these patients, 37 were confirmed as having dengue and completed the study; in total, 19 dengue patients received chloroquine and 18 received placebo. There was no significant difference in the duration of the disease or the degree and days of fever. However, 12 patients (63%) with confirmed dengue reported a substantial decrease in pain intensity and a great improvement in their ability to perform daily activities (p = 0.0004) while on the medication and the symptoms returned immediately after these patients stopped taking the medication. The same effect was not observed in patients with diseases other than dengue. Therefore, this study shows that patients with dengue treated with chloroquine had an improvement in their quality of life and were able to resume their daily activities. However, as chloroquine did not alter the duration of the disease or the intensity and days of fever, further studies are necessary to confirm the clinical effects and to assess the side effects of chloroquine in dengue patients. PMID:23903975

  16. Dengue blood analysis by Raman spectroscopy

    NASA Astrophysics Data System (ADS)

    Rehman, A.; Anwar, S.; Firdous, S.; Ahmed, M.; Rasheed, R.; Nawaz, M.

    2012-06-01

    In this work Raman spectra of normal and dengue infected serum and whole blood were analyzed. In normal whole blood and serum characteristic peaks were observed when excited at 442 and 532 nm. In dengue whole blood and serum all peaks found to be blue shifted with reduced Raman intensity. Dengue whole blood and serum shows two peaks at 1614 and 1750 cm-1 which are due to presence of Immunoglobulin antibodies IgG and IgM. Whole study provides a route of information for diagnosis of dengue viral infection.

  17. Exploratory space-time analysis of dengue incidence in Trinidad: a retrospective study using travel hubs as dispersal points, 1998–2004

    PubMed Central

    2014-01-01

    Background Dengue is an acute arboviral disease responsible for most of the illness and death in tropical and subtropical regions. Over the last 25 years there has been increase epidemic activity of the disease in the Caribbean, with the co-circulation of multiple serotypes. An understanding of the space and time dynamics of dengue could provide health agencies with important clues for reducing its impact. Methods Dengue Haemorrhagic Fever (DHF) cases observed for the period 1998–2004 were georeferenced using Geographic Information System software. Spatial clustering was calculated for individual years and for the entire study period using the Nearest Neighbor Index. Space and time interaction between DHF cases was determined using the Knox Test while the Nearest Neighbor Hierarchical method was used to extract DHF hot spots. All space and time distances calculated were validated using the Pearson r significance test. Results Results shows that (1) a decrease in mean distance between DHF cases correlates with activity leading up to an outbreak, (2) a decrease in temporal distance between DHF cases leads to increased geographic spread of the disease, with an outbreak occurrence about every 2 years, and (3) a general pattern in the movement of dengue incidents from more rural to urban settings leading up to an outbreak with hotspot areas associated with transportation hubs in Trinidad. Conclusion Considering only the spatial dimension of the disease, results suggest that DHF cases become more concentrated leading up to an outbreak. However, with the additional consideration of time, results suggest that when an outbreak occurs incidents occur more rapidly in time leading to a parallel increase in the rate of distribution of the disease across space. The results of this study can be used by public health officers to help visualize and understand the spatial and temporal patterns of dengue, and to prepare warnings for the public. Dengue space-time patterns and hotspot detection will provide useful information to support public health officers in their efforts to control and predict dengue spread over critical hotspots allowing better allocation of resources. PMID:25052242

  18. Description of outbreaks of healthcare associated infections related to compounding pharmacies, 2000-2012

    PubMed Central

    Staes, Catherine; Jacobs, Jason; Mayer, Jeanmarie; Allen, Jill

    2013-01-01

    Purpose The 2012 multistate fungal meningitis outbreak caused by contaminated methylprednisolone suggests that contaminated compounded drugs can pose a public health threat. The problem has not been well described. Our objective was to systematically review the literature to describe: a) features of infectious outbreaks associated with exposure to contaminated drugs produced by compounding pharmacies, b) sterile compounding procedures that caused microbial contamination, and c) outbreak features relevant for detection and investigation. Methods We searched PubMed (reviewing 850 citations) and the CDC and FDA Web sites to identify infectious outbreaks associated with compounding pharmacies outside the hospital setting between January 2000 and November 2012. We extracted information from peer-reviewed literature, FDA and CDC documents, meeting abstracts, and congressional testimony. Results Between 2000 and prior to the 2012 fungal meningitis outbreak, 11 infectious outbreaks from contaminated compounded drugs were reported involving 207 case-patients with 17 deaths (8.2% case fatality rate). The 2012 meningitis outbreak increased totals almost 5-fold. Half the outbreaks involved case-patients in more than 1 state. Three outbreaks involved ophthalmic drugs: trypan blue and Brilliant Blue-G ophthalmic solutions used during surgery, and triamcinolone and bevacizumab for intravitreal injection. Remaining outbreaks involved corticosteroids (n=2), heparin flush solutions (n=2), cardioplegia, intravenous magnesium sulfate, total parenteral nutrition, and fentanyl. The outbreaks were caused by pathogens commonly associated with healthcare associated infections (n=6), common skin commensals (n=1), and organisms that rarely cause infection (n=5). Morbidity was substantial, including vision loss; mortality rates during earlier outbreaks were similar to the 2012 meningitis outbreak. A variety of problems with sterile procedures were found. No single source reported all outbreaks. Conclusion Sporadic but serious infectious outbreaks associated with contaminated drugs from compounding pharmacies occurred before the 2012 fungal meningitis outbreak. These outbreaks illustrate root causes that could be addressed with preventive policies and practices. PMID:23867487

  19. Origin of the Dengue Fever Mosquito, Aedes aegypti, in California

    PubMed Central

    Gloria-Soria, Andrea; Brown, Julia E.; Kramer, Vicki; Hardstone Yoshimizu, Melissa; Powell, Jeffrey R.

    2014-01-01

    Dengue fever is among the most widespread vector-borne infectious diseases. The primary vector of dengue is the Aedes aegypti mosquito. Ae. aegypti is prevalent in the tropics and sub-tropics and is closely associated with human habitats outside its native range of Africa. While long established in the southeastern United States of America where dengue is re-emerging, breeding populations have never been reported from California until the summer of 2013. Using 12 highly variable microsatellite loci and a database of reference populations, we have determined that the likely source of the California introduction is the southeastern United States, ruling out introductions from abroad, from the geographically closer Arizona or northern Mexico populations, or an accidental release from a research laboratory. The power to identify the origin of new introductions of invasive vectors of human disease relies heavily on the availability of a panel of reference populations. Our work demonstrates the importance of generating extensive reference databases of genetically fingerprinted human-disease vector populations to aid public health efforts to prevent the introduction and spread of vector-borne diseases. PMID:25077804

  20. Characterization of retrovirus-based reporter viruses pseudotyped with the precursor membrane and envelope glycoproteins of four serotypes of dengue viruses

    SciTech Connect

    Hu, H.-P.; Hsieh, S.-C. [Institute of Microbiology, College of Medicine, National Taiwan University, No 1 Sec1 Jen-Ai Rd, Taipei 100, Taiwan (China); King, C.-C. [Institute of Epidemiology, College of Public Health, National Taiwan University, No 1 Sec1 Jen-Ai Rd, Taipei 100, Taiwan (China); Wang, W.-K. [Institute of Microbiology, College of Medicine, National Taiwan University, No 1 Sec1 Jen-Ai Rd, Taipei 100, Taiwan (China); Department of Internal Medicine, National Taiwan University Hospital, No 7 Chung-Shan S Rd, Taipei 100, Taiwan (China)], E-mail: wwang60@yahoo.com

    2007-11-25

    In this study, we successfully established retrovirus-based reporter viruses pseudotyped with the precursor membrane and envelope (PrM/E) proteins of each of the four serotypes of dengue viruses, which caused the most important arboviral diseases in this century. Co-sedimentation of the dengue E protein and HIV-1 core proteins by sucrose gradient analysis of the pseudotype reporter virus of dengue virus type 2, D2(HIVluc), and detection of HIV-1 core proteins by immunoprecipitation with anti-E monoclonal antibody suggested that dengue viral proteins were incorporated into the pseudotype viral particles. The infectivity in target cells, as assessed by the luciferase activity, can be inhibited by the lysosomotropic agents, suggesting a pH-dependent mechanism of entry. Amino acid substitutions of the leucine at position 107, a critical residue at the fusion loop of E protein, with lysine resulted in severe impairment in infectivity, suggesting that entry of the pseudotype reporter virus is mediated through the fusogenic properties of E protein. With more and more dengue viral sequences available from different outbreaks worldwide, this sensitive and convenient tool has the potential to facilitate molecular characterization of the PrM/E proteins of dengue field isolates.

  1. CDC Vital Signs: Preventing Norovirus Outbreaks

    MedlinePLUS

    ... image and text. What Can Be Done Federal government is: Working with state and local agencies to ... using genome sequencing and analysis. State and local governments can: Adopt and enforce all provisions of the ...

  2. Novel vaccination approach for dengue infection based on recombinant immune complex universal platform.

    PubMed

    Kim, Mi-Young; Reljic, Rajko; Kilbourne, Jacquelyn; Ceballos-Olvera, Ivonne; Yang, Moon-Sik; Reyes-Del Valle, Jorge; Mason, Hugh S

    2015-04-01

    Dengue infection is on the rise in many endemic areas of the tropics. Vaccination remains the most realistic strategy for prevention of this potentially fatal viral disease but there is currently no effective vaccine that could protect against all four known serotypes of the dengue virus. This study describes the generation and testing of a novel vaccination approach against dengue based on recombinant immune complexes (RIC). We modelled the dengue RIC on the existing Ebola RIC (Phoolcharoen, et al. Proc Natl Acad Sci USA 2011;108(Dec (51)):20695) but with a key modification that allowed formation of a universal RIC platform that can be easily adapted for use for other pathogens. This was achieved by retaining only the binding epitope of the 6D8 ant-Ebola mAb, which was then fused to the consensus dengue E3 domain (cEDIII), resulting in a hybrid dengue-Ebola RIC (DERIC). We expressed human and mouse versions of these molecules in tobacco plants using a geminivirus-based expression system. Following purification from the plant extracts by protein G affinity chromatography, DERIC bound to C1q component of complement, thus confirming functionality. Importantly, following immunization of mice, DERIC induced a potent, virus-neutralizing anti-cEDIII humoral immune response without exogenous adjuvants. We conclude that these self-adjuvanting immunogens have the potential to be developed as a novel vaccine candidate for dengue infection, and provide the basis for a universal RIC platform for use with other antigens. PMID:25728317

  3. Escherichia coli O 157: outbreak in a day nursery.

    PubMed

    Allaby, M A; Mayon-White, R

    1995-01-01

    Seventeen out of 54 preschool children at a day nursery became infected with Escherichia coli O 157. The nursery outbreak formed part of a wider community outbreak, whose source was not identified. Epidemiological investigation suggested that the nursery outbreak resulted from person to person spread. Children with diarrhoea or a positive faecal specimen were excluded until their symptoms had resolved and one negative faecal specimen had been obtained. Children who were asymptomatic throughout were not excluded. This policy appeared to be effective in preventing further spread of infection within the nursery. PMID:7531569

  4. Evolution and heterogeneity of multiple serotypes of Dengue virus in Pakistan, 2006–2011

    PubMed Central

    2013-01-01

    Background Even though dengue has been recognized as one of the major public health threats in Pakistan, the understanding of its molecular epidemiology is still limited. The genotypic diversity of Dengue virus (DENV) serotypes involved in dengue outbreaks since 2005 in Pakistan is not well studied. Here, we investigated the origin, diversity, genetic relationships and geographic distribution of DENV to understand virus evolution during the recent expansion of dengue in Pakistan. Methods The study included 200 sera obtained from dengue-suspected patients from 2006 to 2011. DENV infection was confirmed in 94 (47%) sera by a polymerase chain reaction assay. These included 36 (38.3%) DENV-2, 57 DENV-3 (60.6%) and 1 DENV-4 (1.1%) cases. Sequences of 13 whole genomes (6 DENV-2, 6 DENV-3 and 1 DENV-4) and 49 envelope genes (26 DENV-2, 22 DENV-3 and 1 DENV-4) were analysed to determine the origin, phylogeny, diversity and selection pressure during virus evolution. Results DENV-2, DENV-3 and DENV-4 in Pakistan from 2006 to 2011 shared 98.5-99.6% nucleotide and 99.3-99.9% amino acid similarity with those circulated in the Indian subcontinent during the last decade. Nevertheless, Pakistan DENV-2 and DENV-3 strains formed distinct clades characterized by amino acid signatures of NS2A-I116T + NS5-K861R and NS3-K590R + NS5-S895L respectively. Each clade consisted of a heterogenous virus population that circulated in Southern (2006–2009) and Northern Pakistan (2011). Conclusions DENV-2, DENV-3 and DENV-4 that circulated during 2006–2011 are likely to have first introduced via the southern route of Pakistan. Both DENV-2 and DENV-3 have undergone in-situ evolution to generate heterogenous populations, possibly driven by sustained local DENV transmission during 2006–2011 periods. While both DENV-2 and DENV-3 continued to circulate in Southern Pakistan until 2009, DENV-2 has spread in a Northern direction to establish in Punjab Province, which experienced a massive dengue outbreak in 2011. PMID:24007412

  5. A case presentation of a fatal dengue myocarditis showing evidence for dengue virus-induced lesion

    PubMed Central

    Miranda, Carlos Henrique; Borges, Marcos de Carvalho; Schmidt, André; Pazin-Filho, Antônio; Rossi, Marcos Antônio; Ramos, Simone Gusmão

    2013-01-01

    Dengue is a prevalent arthropod-borne viral disease in tropical and subtropical areas of the globe. Dengue clinical manifestations include asymptomatic infections; undifferentiated fever; dengue fever, which is characterized by fever, headache, retroorbital pain, myalgia, and arthralgia; and a severe form of the disease denominated dengue haemorrhagic fever/dengue shock syndrome, characterized by haemoconcentration, thrombocytopenia, and bleeding tendency. However, atypical manifestations, such as liver, central nervous system, and cardiac involvement, have been increasingly reported. We report an atypical and rare presentation of dengue disease marked by a dramatic and fatal cardiogenic shock due to acute myocarditis. Histopathological analysis of heart tissue showed several multifocal areas of muscle necrosis and intense interstitial oedema associated with clusters of virus particles inside the cardiomyocytes and in the interstitial space, providing evidence of a possible direct action of dengue virus on myocardium. PMID:24222821

  6. Comparison of Vector Competence of Aedes mediovittatus and Aedes aegypti for Dengue Virus: Implications for Dengue Control in the Caribbean

    PubMed Central

    Poole-Smith, B. Katherine; Hemme, Ryan R.; Delorey, Mark; Felix, Gilberto; Gonzalez, Andrea L.; Amador, Manuel; Hunsperger, Elizabeth A.; Barrera, Roberto

    2015-01-01

    Background Aedes mediovittatus mosquitoes are found throughout the Greater Antilles in the Caribbean and often share the same larval habitats with Ae. Aegypti, the primary vector for dengue virus (DENV). Implementation of vector control measures to control dengue that specifically target Ae. Aegypti may not control DENV transmission in Puerto Rico (PR). Even if Ae. Aegypti is eliminated or DENV refractory mosquitoes are released, DENV transmission may not cease when other competent mosquito species like Ae. Mediovittatus are present. To compare vector competence of Ae. Mediovittatus and Ae. Aegypti mosquitoes, we studied relative infection and transmission rates for all four DENV serotypes. Methods To compare the vector competence of Ae. Mediovittatus and Ae. Aegypti, mosquitoes were exposed to DENV 1–4 per os at viral titers of 5–6 logs plaque-forming unit (pfu) equivalents. At 14 days post infectious bloodmeal, viral RNA was extracted and tested by qRT-PCR to determine infection and transmission rates. Infection and transmission rates were analyzed with a generalized linear model assuming a binomial distribution. Results Ae. Aegypti had significantly higher DENV-4 infection and transmission rates than Ae. mediovittatus. Conclusions This study determined that Ae. Mediovittatus is a competent DENV vector. Therefore dengue prevention programs in PR and the Caribbean should consider both Ae. Mediovittatus and Ae. Aegypti mosquitoes in their vector control programs. PMID:25658951

  7. Evaluation of molecular strategies to develop a live dengue vaccine

    Microsoft Academic Search

    C. J Lai; M Bray; R Men; A Cahour; W Chen; H Kawano; M Tadano; K Hiramatsu; I Tokimatsu; A Pletnev; S Arakai; G Shameem; M Rinaudo

    1998-01-01

    Background: Millions of individuals are estimated to become infected with dengue virus each year, particularly in tropical and subtropical regions. Mortality is low but infection can lead to a severe form of dengue, characterised by haemorrhage and shock. A safe and effective vaccine against dengue is still not available.Objective: To use the successful construction of dengue type 4 virus (DEN4)

  8. Policy Platform Assessing the Potential of a Candidate Dengue Vaccine

    E-print Network

    Rohani, Pej

    -attenuated, tetravalent, chimeric yellow fever dengue vaccine-- commenced Phase II and Phase IIB clinical trials in 2009-sense RNA viruses (genus Flavivirus, family Flaviviridae) that are the etiological agents of dengue fever ranges from asymptomatic infection to life threatening dengue hemorrhagic fever (DHF) and dengue shock

  9. (Dengue Fever reported in Osceola County) OSCEOLA COUNTY HEALTH DEPARTMENT

    E-print Network

    Watson, Craig A.

    (Dengue Fever reported in Osceola County) OSCEOLA COUNTY HEALTH DEPARTMENT ISSUES PUBLIC HEALTH of two cases of dengue fever in Osceola County. Dengue is one of several mosquito-borne illnesses was not acquired locally. Symptoms of dengue fever vary according to the age of the patient. Infants and young

  10. Restriction enzyme analysis of American region dengue viruses

    Microsoft Academic Search

    V. Vorndam; R. M. R. Nogueira; D. W. Trent

    1994-01-01

    Summary Restriction fragment heterogeneity of Hae III digestion products of cDNA to virion RNA was used to map the distribution of dengue virus topotypes found in the American region. By comparing the electrophoretic patterns of fragments produced, dengue virus isolates were placed in groups that agreed with those previously determined by oligonucleotide fingerprinting. Dengue-1 and dengue-4 viruses occur throughout the

  11. Thailand Momentum on Policy and Practice in Local Legislation on Dengue Vector Control

    PubMed Central

    Bhumiratana, Adisak; Intarapuk, Apiradee; Chujun, Suriyo; Kaewwaen, Wuthichai; Sorosjinda-Nunthawarasilp, Prapa; Koyadun, Surachart

    2014-01-01

    Over a past decade, an administrative decentralization model, adopted for local administration development in Thailand, is replacing the prior centralized (top-down) command system. The change offers challenges to local governmental agencies and other public health agencies at all the ministerial, regional, and provincial levels. A public health regulatory and legislative framework for dengue vector control by local governmental agencies is a national topic of interest because dengue control program has been integrated into healthcare services at the provincial level and also has been given priority in health plans of local governmental agencies. The enabling environments of local administrations are unique, so this critical review focuses on the authority of local governmental agencies responsible for disease prevention and control and on the functioning of local legislation with respect to dengue vector control and practices. PMID:24799896

  12. Planning for smallpox outbreaks

    NASA Astrophysics Data System (ADS)

    Ferguson, Neil M.; Keeling, Matt J.; John Edmunds, W.; Gani, Raymond; Grenfell, Bryan T.; Anderson, Roy M.; Leach, Steve

    2003-10-01

    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.

  13. Dengue, Urbanization and Globalization: The Unholy Trinity of the 21st Century

    PubMed Central

    Gubler, Duane J.

    2011-01-01

    Dengue is the most important arboviral disease of humans with over half of the world’s population living in areas of risk. The frequency and magnitude of epidemic dengue have increased dramatically in the past 40 years as the viruses and the mosquito vectors have both expanded geographically in the tropical regions of the world. There are many factors that have contributed to this emergence of epidemic dengue, but only three have been the principal drivers: 1) urbanization, 2) globalization and 3) lack of effective mosquito control. The dengue viruses have fully adapted to a human-Aedes aegypti-human transmission cycle, in the large urban centers of the tropics, where crowded human populations live in intimate association with equally large mosquito populations. This setting provides the ideal home for maintenance of the viruses and the periodic generation of epidemic strains. These cities all have modern airports through which 10s of millions of passengers pass each year, providing the ideal mechanism for transportation of viruses to new cities, regions and continents where there is little or no effective mosquito control. The result is epidemic dengue. This paper discusses this unholy trinity of drivers, along with disease burden, prevention and control and prospects for the future. PMID:22500131

  14. Mosquito age and dengue transmission

    NSDL National Science Digital Library

    The Grand Challenges in Global Health Initiative

    This online portal features a research project funded by The Grand Challenges in Global Health Initiative to develop new strategies to control mosquitoes that transmit human disease. Specifically, the project is focused on a method to reduce dengue transmission using naturally occurring bacterial symbionts that reduce mosquito life span. The site includes a background of this work, participating research programs and researchers, project publications, current progress, news and events, and FAQs.

  15. 2nd International External Quality Control Assessment for the Molecular Diagnosis of Dengue Infections

    PubMed Central

    Domingo, Cristina; Niedrig, Matthias; Teichmann, Anette; Kaiser, Marco; Rumer, Leonid; Jarman, Richard G.; Donoso-Mantke, Oliver

    2010-01-01

    Background Currently dengue viruses (DENV) pose an increasing threat to over 2.5 billion people in over 100 tropical and sub-tropical countries worldwide. International air travel is facilitating rapid global movement of DENV, increasing the risk of severe dengue epidemics by introducing different serotypes. Accurate diagnosis is critical for early initiation of preventive measures. Different reverse transcriptase PCR (RT-PCR) methods are available, which should be evaluated and standardized. Epidemiological and laboratory-based surveillance is required to monitor and guide dengue prevention and control programmes, i.e., by mosquito control or possible vaccination (as soon as an effective and safe vaccine becomes available). Objective The purpose of the external quality assurance (EQA) study described is to assess the efficiency and accuracy of dengue molecular diagnosis methods applied by expert laboratories. Study Design A panel of 12 human plasma samples was distributed and tested for DENV-specific RNA. The panel comprised 9 samples spiked with different DENV serotypes (DENV-1 to DENV-4), including 10-fold dilution series of DENV-1 and DENV-3. Two specificity controls consisted of a sample with a pool of 4 other flaviviruses and a sample with chikungunya virus. A negative control sample was also included. Results Thirty-seven laboratories (from Europe, Middle East Asia, Asia, the Americas/Caribbean, and Africa) participated in this EQA study, and reports including 46 sets of results were returned. Performance among laboratories varied according to methodologies used. Only 5 (10.9%) data sets met all criteria with optimal performance, and 4 (8.7%) with acceptable performance, while 37 (80.4%) reported results showed the need for improvement regarding accomplishment of dengue molecular diagnosis. Failures were mainly due to lack of sensitivity and the presence of false positives. Conclusions The EQA provides information on each laboratory's efficacy of RT-PCR techniques for dengue diagnosis and indicates for most laboratories an urgent need to improve sensitivity and specificity. PMID:20957194

  16. Dengue and Malaria in Cayenne Hospital,

    E-print Network

    Paris-Sud XI, Université de

    Concurrent Dengue and Malaria in Cayenne Hospital, French Guiana Bernard Carme, Severine Matheus, Gerd Donutil, Olivia Raulin, Mathieu Nacher, and Jacques Morvan Dengue­malaria co-infection reports cases) and 393 had malaria (371 acute malaria); 17 had both. Diagnosis of 1 of these 2 infections should

  17. Typhoid and dengue coinfection: case reports.

    PubMed

    Bansal, Rohit; Bansal, Priya; Tomar, Laxmikant Ramkumarsingh

    2015-01-01

    Both dengue and typhoid fever have emerged as major public health problems in India. Coinfection with both these diseases is rarely reported. Here we report two confirmed cases of concurrent illness of dengue with typhoid fever; both patients were managed as outpatients and recovered completely. PMID:25315238

  18. Dengue and Chikungunya Vector Control Pocket Guide

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This technical guide consolidates information and procedures for surveillance and control of mosquitoes that transmit dengue and chikungunya viruses. The guide focuses on mosquitoes that transmit dengue but also makes reference to chikungunya and yellow fever because the pathogens that cause these ...

  19. Planning for smallpox outbreaks

    Microsoft Academic Search

    Matt J. Keeling; W. John Edmunds; Raymond Gani; Bryan T. Grenfell; Roy M. Anderson; Steve Leach; Neil M. Ferguson

    2003-01-01

    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

  20. RNAi: antiviral therapy against dengue virus

    PubMed Central

    Idrees, Sobia; Ashfaq, Usman A

    2013-01-01

    Dengue virus infection has become a global threat affecting around 100 countries in the world. Currently, there is no licensed antiviral agent available against dengue. Thus, there is a strong need to develop therapeutic strategies that can tackle this life threatening disease. RNA interference is an important and effective gene silencing process which degrades targeted RNA by a sequence specific process. Several studies have been conducted during the last decade to evaluate the efficiency of siRNA in inhibiting dengue virus replication. This review summarizes siRNAs as a therapeutic approach against dengue virus serotypes and concludes that siRNAs against virus and host genes can be next generation treatment of dengue virus infection. PMID:23620845

  1. RNAi: antiviral therapy against dengue virus.

    PubMed

    Idrees, Sobia; Ashfaq, Usman A

    2013-03-01

    Dengue virus infection has become a global threat affecting around 100 countries in the world. Currently, there is no licensed antiviral agent available against dengue. Thus, there is a strong need to develop therapeutic strategies that can tackle this life threatening disease. RNA interference is an important and effective gene silencing process which degrades targeted RNA by a sequence specific process. Several studies have been conducted during the last decade to evaluate the efficiency of siRNA in inhibiting dengue virus replication. This review summarizes siRNAs as a therapeutic approach against dengue virus serotypes and concludes that siRNAs against virus and host genes can be next generation treatment of dengue virus infection. PMID:23620845

  2. Dengue fever: a Wikipedia clinical review.

    PubMed

    Heilman, James M; De Wolff, Jacob; Beards, Graham M; Basden, Brian J

    2014-01-01

    Dengue fever, also known as breakbone fever, is a mosquito-borne infectious tropical disease caused by the dengue virus. Symptoms include fever, headache, muscle and joint pains, and a characteristic skin rash that is similar to measles. In a small proportion of cases, the disease develops into life-threatening dengue hemorrhagic fever, which results in bleeding, thrombocytopenia, and leakage of blood plasma, or into dengue shock syndrome, in which dangerously low blood pressure occurs. Treatment of acute dengue fever is supportive, with either oral or intravenous rehydration for mild or moderate disease and use of intravenous fluids and blood transfusion for more severe cases. Along with attempts to eliminate the mosquito vector, work is ongoing to develop a vaccine and medications targeted directly at the virus. PMID:25426178

  3. Symptoms and What To Do If You Think You Have Dengue

    MedlinePLUS

    ... 4 RT-PCR Assay Case Definition Dengue Panel Project Education/Training Patient Education & Training Media Resources Dengue Clinical Case Management (DCCM) Publications and Related Links Dengue Branch Dengue ...

  4. Dengue fever in Europe: could there be an epidemic in the future?

    PubMed

    Parreira, Ricardo; Sousa, Carla A

    2015-01-01

    Dengue virus (DENV) is the arbovirus with the widest impact on human health. Although its dispersal is partially conditioned by environmental constraints that limit the distribution of its main vector (Aedes aegypti), DENV has been spreading geographically in recent times, but mostly afflicting tropical and subtropical regions. With no prophylactic vaccine or specific therapeutics available, vector control remains the best alternative to restrain its circulation. Moreover, the establishment of thriving vector populations in peri urban environments brings humans and viruses together, opening the possibility for the occurrence of unexpected outbreaks. Europe is no exception: such was the case of Madeira in 2012. In addition to its impact on the health of the local population, health services, and economy, this outbreak revealed how difficult it may be to control the circulation of pathogenic arboviruses, especially taking into consideration that Europe is already partially colonized by another DENV vector, Aedes albopictus. PMID:25399556

  5. Abiotic determinants to the spatial dynamics of dengue fever in Guangzhou.

    PubMed

    Li, Sen; Tao, Haiyan; Xu, Yong

    2013-05-01

    Dengue fever (DF) is a mosquito-borne disease that significantly endangers the well-being of people in most tropical Asia-Pacific areas. The transmission of DF is inherently a spatial process, requiring susceptible humans encountering infectious mosquito. The relationships between humans, mosquito and environment underpin the dynamics and patterns of the epidemic. In this article, the objective is to find out the key abiotic factors in the spatial dynamics of DF. An interdisciplinary study has been carried out by taking advantage of statistics, geographical information science, and remote sensing technologies. The case study is the DF outbreak in the Chinese city of Guangzhou throughout the year of 2002--the most serious DF outbreak in the recent decade. This study shows that the presence and abundance of DF cases can be associated with (a) socioeconomic factors relating to urbanization and (b) meteorological factors favoring mosquito survival. PMID:21852418

  6. Assessing Disparities of Dengue Virus Transmission Risk across the US-Mexican Border Using a Climate Driven Vector-Epidemiological Model

    NASA Technical Reports Server (NTRS)

    Morin, Cory; Monaghan, Andrew; Quattrochi, Dale; Crosson, William; Hayden, Mary; Ernst, Kacey

    2015-01-01

    Dengue fever is a mosquito-borne viral disease reemerging throughout much of the tropical Americas. Dengue virus transmission is explicitly influenced by climate and the environment through its primary vector, Aedes aegypti. Temperature regulates Ae. aegypti development, survival, and replication rates as well as the incubation period of the virus within the mosquito. Precipitation provides water for many of the preferred breeding habitats of the mosquito, including buckets, old tires, and other places water can collect. Although transmission regularly occurs along the border region in Mexico, dengue virus transmission in bordering Arizona has not occurred. Using NASA's TRMM (Tropical Rainfall Measuring Mission) satellite for precipitation input and Daymet for temperature and supplemental precipitation input, we modeled dengue transmission along a US-Mexico transect using a dynamic dengue transmission model that includes interacting vector ecology and epidemiological components. Model runs were performed for 5 cities in Sonora, Mexico and southern Arizona. Employing a Monte Carlo approach, we performed ensembles of several thousands of model simulations in order to resolve the model uncertainty arising from using different combinations of parameter values that are not well known. For cities with reported dengue case data, the top model simulations that best reproduced dengue case numbers were retained and their parameter values were extracted for comparison. These parameter values were used to run simulations in areas where dengue virus transmission does not occur or where dengue fever case data was unavailable. Additional model runs were performed to reveal how changes in climate or parameter values could alter transmission risk along the transect. The relative influence of climate variability and model parameters on dengue virus transmission is assessed to help public health workers prepare location specific infection prevention strategies.

  7. Seafood-associated disease outbreaks in New York, 1980–1994

    Microsoft Academic Search

    Barbara J Wallace; John J Guzewich; Michael Cambridge; Sean Altekruse; Dale L Morse

    1999-01-01

    Background: Seafood-associated disease outbreaks in New York were examined to describe their epidemiology and to identify areas for prevention and control efforts.Methods: We reviewed reports submitted to the New York State Department of Health (NYSDOH) of seafood-associated outbreaks occurring from January 1, 1980, through December 31, 1994.Results: During 1980–1994, 339 seafood-associated outbreaks were reported, resulting in 3959 illnesses, 76 hospitalizations,

  8. Listeriosis Outbreaks and Associated Food Vehicles, United States, 1998–2008

    PubMed Central

    Cartwright, Emily J.; Jackson, Kelly A.; Johnson, Shacara D.; Graves, Lewis M.; Mahon, Barbara E.

    2013-01-01

    Listeria monocytogenes, a bacterial foodborne pathogen, can cause meningitis, bacteremia, and complications during pregnancy. This report summarizes listeriosis outbreaks reported to the Foodborne Disease Outbreak Surveillance System of the Centers for Disease Control and Prevention during 1998–2008. The study period includes the advent of PulseNet (a national molecular subtyping network for outbreak detection) in 1998 and the Listeria Initiative (enhanced surveillance for outbreak investigation) in 2004. Twenty-four confirmed listeriosis outbreaks were reported during 1998–2008, resulting in 359 illnesses, 215 hospitalizations, and 38 deaths. Outbreaks earlier in the study period were generally larger and longer. Serotype 4b caused the largest number of outbreaks and outbreak-associated cases. Ready-to-eat meats caused more early outbreaks, and novel vehicles (i.e., sprouts, taco/nacho salad) were associated with outbreaks later in the study period. These changes may reflect the effect of PulseNet and the Listeria Initiative and regulatory initiatives designed to prevent contamination in ready-to-eat meat and poultry products. PMID:23260661

  9. A review of dengue fever incidence in Kota Bharu, Kelantan, Malaysia during the years 1998-2003.

    PubMed

    Hussin, Narwani; Jaafar, Jesni; Naing, Nyi Nyi; Mat, Hamzah Ag; Muhamad, Abd Haris; Mamat, Mohd Noor

    2005-09-01

    Dengue is the most common and widespread arthropod borne arboviral infection in the world today. It is estimated that there are at least 100 million cases of dengue fever (DF) annually and 500,000 cases of dengue hemorrhagic fever (DHF) which require hospitalization. In Malaysia, it has become a major public health problem. Malaysia recorded 19,544 dengue cases in 1997, the highest recorded since the disease was made notifiable in the country. Of 19,544 cases, 806 were DHF with 50 deaths. The objectives of this analysis were to describe the incidence of dengue fever and dengue hemorrhagic fever in Kota Bharu, Kelantan, Malaysia for the years 1998-2003 and to explore the characteristics of dengue fever and dengue hemorrhagic fever in Kota Bharu, Kelantan, Malaysia for years 1998-2003. A total of 4,716 dengue cases were notified involving 4,476 (94.9%) DF and 240 (5.1%) DHF cases, which increased though the years. The highest incidence was in January (701 or 14.9%), while the lowest was in May (188 or 4.0%). Forty percent of cases (n=1,890) were in the 15-29 year old group. The Majority were Malays (4,062 or 86.1%) and 2,602 or 55.2% were male. A total of 4,477 cases (95%) were local cases and 4,289 or 91% came from the urban area. For priority areas, 3,772 (80%) were from priority 1. More than half the cases had positive serology results. All symptoms occurred in more than 96% of cases and fever was the commonest (99.7%). The mean values for age, temperature, systolic and diastolic blood pressure (BP) were 27.8 +/- 15.4 years, 37.9 +/- 0.90 degrees C, 115 +/- 15.2 mmHg and 73 +/- 11.1 mmHg, respectively. The mean value for the time interval between the onset of symptoms and diagnosis, onset of symptoms and notification and time of diagnosis to notification were 5.1 +/- 2.3, 5.9 +/- 2.5 and 0.8 +/- 1.1 days, respectively. There were associations between the types of dengue and classification, area and priority area. Among the symptoms, the association was only seen in joint pain. The mean significant differences between DF and DHF were found in age and systolic blood pressure. The incidence of dengue in Kota Bharu is comparable to that in Malaysia. The increase in the number of cases needs to be addressed promptly with effective surveillance, prevention and control programs. PMID:16438143

  10. Challenges and future perspective for dengue vector control in the Western Pacific Region

    PubMed Central

    Christophel, Eva Maria; Gopinath, Deyer; Abdur, Rashid Md.; Vectorborne, Other; Diseases, Parasitic

    2011-01-01

    Dengue remains a significant public health issue in the Western Pacific Region. In the absence of a vaccine, vector control is the mainstay for dengue prevention and control. In this paper we describe vector surveillance and vector control in the Western Pacific countries and areas. Vector surveillance and control strategies used by countries and areas of the Western Pacific Region vary. Vector control strategies include chemical, biological and environmental management that mainly target larval breeding sites. The use of insecticides targeting larvae and adult mosquitoes remains the mainstay of vector control programmes. Existing vector control tools have several limitations in terms of cost, delivery and long-term sustainability. However, there are several new innovative tools in the pipeline. These include Release of Insects Carrying a Dominant Lethal system and Wolbachia, an endosymbiotic bacterium, to inhibit dengue virus in the vector. In addition, the use of biological control such as larvivorous fish in combination with community participation has potential to be scaled up. Any vector control strategy should be selected based on evidence and appropriateness for the entomological and epidemiological setting and carried out in both inter-epidemic and epidemic periods. Community participation and interagency collaboration are required for effective and sustainable dengue prevention and control. Countries and areas are now moving towards integrated vector management. PMID:23908883

  11. Sphingosine 1-Phosphate in Acute Dengue Infection

    PubMed Central

    Gomes, Laksiri; Fernando, Samitha; Fernando, Randika Heshan; Wickramasinghe, Nilanka; Shyamali, Narangoda Liyanage Ajantha

    2014-01-01

    Background Vascular leak is the hallmark of severe dengue infections and leads to complications such as shock and multi-organ failure. Although many mediators have been implicated in the vascular leak in dengue, the role of sphingosine 1-phosphate (S1P) has not been investigated. Metholodology/Principal findings As S1P has been shown to be important in barrier integrity, we assessed the S1P levels in 28 patients with acute dengue and 12 healthy individuals. The S1P levels were significantly lower in patients with acute dengue (p?=?0.002) and the levels in patients with grade IV dengue haemorrhagic fever (DHF) were significantly lower than those with dengue fever (p?=?0.005). We then investigated the kinetics of S1P levels throughout the course of the illness in another 32 patients in serum samples obtained twice a day. We found that S1P levels were low throughout the course of illness and S1P levels were <0.5 µM in 12/23 patients with DHF when compared to 1/9 with DF. Conclusions/Significance As S1P has shown to be important in the endothelial barrier integrity and increases transendothelial resistance, low levels of S1P in acute dengue infection are likely to contribute to increased vascular permeability. PMID:25409037

  12. Quantifying Reporting Timeliness to Improve Outbreak Control

    PubMed Central

    Swaan, Corien; van Steenbergen, Jim; Kretzschmar, Mirjam

    2015-01-01

    The extent to which reporting delays should be reduced to gain substantial improvement in outbreak control is unclear. We developed a model to quantitatively assess reporting timeliness. Using reporting speed data for 6 infectious diseases in the notification system in the Netherlands, we calculated the proportion of infections produced by index and secondary cases until the index case is reported. We assumed interventions that immediately stop transmission. Reporting delays render useful only those interventions that stop transmission from index and secondary cases. We found that current reporting delays are adequate for hepatitis A and B control. However, reporting delays should be reduced by a few days to improve measles and mumps control, by at least 10 days to improve shigellosis control, and by at least 5 weeks to substantially improve pertussis control. Our method provides quantitative insight into the required reporting delay reductions needed to achieve outbreak control and other transmission prevention goals. PMID:25625374

  13. Quantifying reporting timeliness to improve outbreak control.

    PubMed

    Marinovi?, Axel Bona?i?; Swaan, Corien; van Steenbergen, Jim; Kretzschmar, Mirjam

    2015-02-01

    The extent to which reporting delays should be reduced to gain substantial improvement in outbreak control is unclear. We developed a model to quantitatively assess reporting timeliness. Using reporting speed data for 6 infectious diseases in the notification system in the Netherlands, we calculated the proportion of infections produced by index and secondary cases until the index case is reported. We assumed interventions that immediately stop transmission. Reporting delays render useful only those interventions that stop transmission from index and secondary cases. We found that current reporting delays are adequate for hepatitis A and B control. However, reporting delays should be reduced by a few days to improve measles and mumps control, by at least 10 days to improve shigellosis control, and by at least 5 weeks to substantially improve pertussis control. Our method provides quantitative insight into the required reporting delay reductions needed to achieve outbreak control and other transmission prevention goals. PMID:25625374

  14. Estimating the basic reproduction number for single-strain dengue fever epidemics

    PubMed Central

    2014-01-01

    Background Dengue, an infectious tropical disease, has recently emerged as one of the most important mosquito-borne viral diseases in the world. We perform a retrospective analysis of the 2011 dengue fever epidemic in Pakistan in order to assess the transmissibility of the disease. We obtain estimates of the basic reproduction number R0 from epidemic data using different methodologies applied to different epidemic models in order to evaluate the robustness of our estimate. Results We first estimate model parameters by fitting a deterministic ODE vector-host model for the transmission dynamics of single-strain dengue to the epidemic data, using both a basic ordinary least squares (OLS) as well as a generalized least squares (GLS) scheme. Moreover, we perform the same analysis for a direct-transmission ODE model, thereby allowing us to compare our results across different models. In addition, we formulate a direct-transmission stochastic model for the transmission dynamics of dengue and obtain parameter estimates for the stochastic model using Markov chain Monte Carlo (MCMC) methods. In each of the cases we have considered, the estimate for the basic reproduction number R0 is initially greater than unity leading to an epidemic outbreak. However, control measures implemented several weeks after the initial outbreak successfully reduce R0 to less than unity, thus resulting in disease elimination. Furthermore, it is observed that there is strong agreement in our estimates for the pre-control value of R0, both across different methodologies as well across different models. However, there are also significant differences between our estimates for the post-control value of the basic reproduction number across the two different models. Conclusion In conclusion, we have obtained robust estimates for the value of the basic reproduction number R0 associated with the 2011 dengue fever epidemic before the implementation of public health control measures. Furthermore, we have shown that there is close agreement between our estimates for the post-control value of R0 across the different methodologies. Nevertheless, there are also significant differences between the estimates for the post-control value of R0 across the two different models. PMID:24708869

  15. Consequences of the Expanding Global Distribution of Aedes albopictus for Dengue Virus Transmission

    PubMed Central

    Lambrechts, Louis; Scott, Thomas W.; Gubler, Duane J.

    2010-01-01

    The dramatic global expansion of Aedes albopictus in the last three decades has increased public health concern because it is a potential vector of numerous arthropod-borne viruses (arboviruses), including the most prevalent arboviral pathogen of humans, dengue virus (DENV). Ae. aegypti is considered the primary DENV vector and has repeatedly been incriminated as a driving force in dengue's worldwide emergence. What remains unresolved is the extent to which Ae. albopictus contributes to DENV transmission and whether an improved understanding of its vector status would enhance dengue surveillance and prevention. To assess the relative public health importance of Ae. albopictus for dengue, we carried out two complementary analyses. We reviewed its role in past dengue epidemics and compared its DENV vector competence with that of Ae. aegypti. Observations from “natural experiments” indicate that, despite seemingly favorable conditions, places where Ae. albopictus predominates over Ae. aegypti have never experienced a typical explosive dengue epidemic with severe cases of the disease. Results from a meta-analysis of experimental laboratory studies reveal that although Ae. albopictus is overall more susceptible to DENV midgut infection, rates of virus dissemination from the midgut to other tissues are significantly lower in Ae. albopictus than in Ae. aegypti. For both indices of vector competence, a few generations of mosquito colonization appear to result in a relative increase of Ae. albopictus susceptibility, which may have been a confounding factor in the literature. Our results lead to the conclusion that Ae. albopictus plays a relatively minor role compared to Ae. aegypti in DENV transmission, at least in part due to differences in host preferences and reduced vector competence. Recent examples of rapid arboviral adaptation to alternative mosquito vectors, however, call for cautious extrapolation of our conclusion. Vector status is a dynamic process that in the future could change in epidemiologically important ways. PMID:20520794

  16. The epidemiology of published norovirus outbreaks: a systematic review of risk factors associated with attack rate and genogroup

    PubMed Central

    Matthews, J. E.; Dickey, B. W.; Miller, R. D.; Felzer, J. R.; Dawson, B. P.; Lee, A. S.; Rocks, J. J.; Kiel, J.; Montes, J. S.; Moe, C. L.; Eisenberg, J. N. S.; Leon, J. S.

    2012-01-01

    SUMMARY The purpose of this study was to examine global epidemiological trends in human norovirus (NoV) outbreaks by transmission route and setting, and describe relationships between these characteristics, viral attack rates, and the occurrence of genogroup I (GI) or genogroup II (GII) strains in outbreaks. We analysed data from 902 RT-PCR-confirmed, human NoV outbreaks extracted from a systematic review of articles published from 1993 to 2011 and indexed under the terms “norovirus” and “outbreak.” Multivariate regression analyses demonstrated that foodservice and winter outbreaks were significantly associated with higher attack rates. Food- and waterborne outbreaks were associated with multiple strains (GI+GII). Waterborne outbreaks were significantly associated with GI strains, while healthcare-related and winter outbreaks were associated with GII strains. These results identify important trends for epidemic NoV detection, prevention, and control. PMID:22444943

  17. Contributing factors to disease outbreaks associated with untreated groundwater.

    PubMed

    Wallender, Erika K; Ailes, Elizabeth C; Yoder, Jonathan S; Roberts, Virginia A; Brunkard, Joan M

    2014-01-01

    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. PMID:24116713

  18. Dengue infection presenting as acute hypokalemic quadriparesis.

    PubMed

    Gupta, N; Garg, A; Chhabra, P

    2014-01-01

    Dengue infection is one of the most common viral hemorrhagic fevers seen in the tropical countries, including India. Its presentation varies from an acute self-resolving febrile illness to life-threatening hemorrhagic shock and multiorgan dysfunction leading to death. Neurological presentations are uncommon and limited to case reports only. Most common neurological manifestations being encephalitis, acute inflammatory demyelinating polyradiculoneuropathy, transverse myelitis, and acute disseminated encephalomyelitis.Hypokalemic quadriparesis as a presenting feature of dengue is extremely rare. Here, we report this case of a 33-year-old female, who presented with hypokalemic quadriparesis and was subsequently diagnosed as dengue infection. PMID:25121379

  19. The many projected futures of dengue.

    PubMed

    Messina, Jane P; Brady, Oliver J; Pigott, David M; Golding, Nick; Kraemer, Moritz U G; Scott, Thomas W; Wint, G R William; Smith, David L; Hay, Simon I

    2015-04-01

    Dengue is a vector-borne disease that causes a substantial public health burden within its expanding range. Several modelling studies have attempted to predict the future global distribution of dengue. However, the resulting projections are difficult to compare and are sometimes contradictory because the models differ in their approach, in the quality of the disease data that they use and in the choice of variables that drive disease distribution. In this Review, we compare the main approaches that have been used to model the future global distribution of dengue and propose a set of minimum criteria for future projections that, by analogy, are applicable to other vector-borne diseases. PMID:25730702

  20. Community Strain of Methicillin-Resistant Staphylococcus aureus Involved in a Hospital Outbreak

    Microsoft Academic Search

    F. G. O'BRIEN; J. W. PEARMAN; M. GRACEY; T. V. RILEY; W. B. GRUBB

    1999-01-01

    Western Australia (WA) has been able to prevent methicillin-resistant Staphylococcus aureus (MRSA) strains from outside of the state from becoming established in its hospitals. Recently, a single-strain outbreak of MRSA occurred in a WA metropolitan teaching hospital following admission of an infected patient from a remote community. The strain responsible for the outbreak was unrelated to any imported strains and

  1. Halting a pneumococcal pneumonia outbreak among United States Marine Corps trainees

    Microsoft Academic Search

    Nancy F Crum; Mark R Wallace; Carla R Lamb; Ava Marie S Conlin; Dennis E Amundson; Patrick E Olson; Margaret A. K Ryan; Ted J Robinson; Gregory C Gray; Kenneth C Earhart

    2003-01-01

    BackgroundStreptococcus pneumoniae is the leading cause of bacterial pneumonia in all age groups. Identifying outbreaks of pneumococcal disease and key risk factors may lead to improvements in vaccination and prevention strategies for high-risk groups. A significant outbreak of S. pneumoniae pneumonia that occurred among Marine recruits is reported here.

  2. Increased Outbreaks Associated with Nonpasteurized Milk, United States, 2007–2012

    PubMed Central

    Behravesh, Casey Barton

    2015-01-01

    The number of US outbreaks caused by nonpasteurized milk increased from 30 during 2007–2009 to 51 during 2010–2012. Most outbreaks were caused by Campylobacter spp. (77%) and by nonpasteurized milk purchased from states in which nonpasteurized milk sale was legal (81%). Regulations to prevent distribution of nonpasteurized milk should be enforced. PMID:25531403

  3. Acute Gastroenteritis Surveillance through the National Outbreak Reporting System, United States

    PubMed Central

    Wikswo, Mary E.; Manikonda, Karunya; Roberts, Virginia A.; Yoder, Jonathan S.; Gould, L. Hannah

    2013-01-01

    Implemented in 2009, the National Outbreak Reporting System provides surveillance for acute gastroenteritis outbreaks in the United States resulting from any transmission mode. Data from the first 2 years of surveillance highlight the predominant role of norovirus. The pathogen-specific transmission pathways and exposure settings identified can help inform prevention efforts. PMID:23876187

  4. Fitting outbreak models to data from many small norovirus outbreaks

    PubMed Central

    O’Dea, Eamon B.; Pepin, Kim M.; Lopman, Ben A.; Wilke, Claus O.

    2014-01-01

    Infectious disease often occurs in small, independent outbreaks in populations with varying characteristics. Each outbreak by itself may provide too little information for accurate estimation of epidemic model parameters. Here we show that using standard stochastic epidemic models for each outbreak and allowing parameters to vary between outbreaks according to a linear predictor leads to a generalized linear model that accurately estimates parameters from many small and diverse outbreaks. By estimating initial growth rates in addition to transmission rates, we are able to characterize variation in numbers of initially susceptible individuals or contact patterns between outbreaks. With simulation, we find that the estimates are fairly robust to the data being collected at discrete intervals and imputation of about half of all infectious periods. We apply the method by fitting data from 75 norovirus outbreaks in health-care settings. Our baseline regression estimates are 0.0037 transmissions per infective–susceptible day, an initial growth rate of 0.27 transmissions per infective day, and a symptomatic period of 3.35 days. Outbreaks in long-term–care facilities had significantly higher transmission and initial growth rates than outbreaks in hospitals. PMID:24593918

  5. Geographic expansion of dengue: the impact of international travel.

    PubMed

    Wilder-Smith, Annelies; Gubler, Duane J

    2008-11-01

    Dengue has emerged as an international public health problem. Reasons for the resurgence of dengue in the tropics and subtropics are complex and include unprecedented urbanization with substandard living conditions, lack of vector control, virus evolution, and international travel. Of all these factors, urbanization has probably had the most impact on the amplification of dengue within a given country, and travel has had the most impact for the spread of dengue from country to country and continent to continent. Epidemics of dengue, their seasonality, and oscillations over time are reflected by the epidemiology of dengue in travelers. Sentinel surveillance of travelers could augment existing national public health surveillance systems. PMID:19061757

  6. Dengue expansion in Africa-not recognized or not happening?

    PubMed

    Jaenisch, Thomas; Junghanss, Thomas; Wills, Bridget; Brady, Oliver J; Eckerle, Isabella; Farlow, Andrew; Hay, Simon I; McCall, Philip J; Messina, Jane P; Ofula, Victor; Sall, Amadou A; Sakuntabhai, Anavaj; Velayudhan, Raman; Wint, G R William; Zeller, Herve; Margolis, Harold S; Sankoh, Osman

    2014-10-01

    An expert conference on Dengue in Africa was held in Accra, Ghana, in February 2013 to consider key questions regarding the possible expansion of dengue in Africa. Four key action points were highlighted to advance our understanding of the epidemiology of dengue in Africa. First, dengue diagnostic tools must be made more widely available in the healthcare setting in Africa. Second, representative data need to be collected across Africa to uncover the true burden of dengue. Third, established networks should collaborate to produce these types of data. Fourth, policy needs to be informed so the necessary steps can be taken to provide dengue vector control and health services. PMID:25271370

  7. Dengue Expansion in Africa—Not Recognized or Not Happening?

    PubMed Central

    Junghanss, Thomas; Wills, Bridget; Brady, Oliver J.; Eckerle, Isabella; Farlow, Andrew; Hay, Simon I.; McCall, Philip J.; Messina, Jane P.; Ofula, Victor; Sall, Amadou A.; Sakuntabhai, Anavaj; Velayudhan, Raman; Wint, G.R. William; Zeller, Herve; Margolis, Harold S.; Sankoh, Osman

    2014-01-01

    An expert conference on Dengue in Africa was held in Accra, Ghana, in February 2013 to consider key questions regarding the possible expansion of dengue in Africa. Four key action points were highlighted to advance our understanding of the epidemiology of dengue in Africa. First, dengue diagnostic tools must be made more widely available in the healthcare setting in Africa. Second, representative data need to be collected across Africa to uncover the true burden of dengue. Third, established networks should collaborate to produce these types of data. Fourth, policy needs to be informed so the necessary steps can be taken to provide dengue vector control and health services. PMID:25271370

  8. Bromeliad-inhabiting mosquitoes in an urban botanical garden of dengue endemic Rio de Janeiro. Are bromeliads productive habitats for the invasive vectors Aedes aegypti and Aedes albopictus?

    PubMed Central

    Mocellin, Márcio Goulart; Simões, Taynãna César; do Nascimento, Teresa Fernandes Silva; Teixeira, Maria Lucia França; Lounibos, Leon Philip; de Oliveira, Ricardo Lourenço

    2012-01-01

    Immatures of both Aedes aegypti and Aedes albopictus have been found in water-holding bromeliad axils in Brazil. Removal of these plants or their treatment with insecticides in public and private gardens have been undertaken during dengue outbreaks in Brazil despite uncertainty as to their importance as productive habitats for dengue vectors. From March 2005-February 2006, we sampled 120 randomly selected bromeliads belonging to 10 species in a public garden less than 200 m from houses in a dengue-endemic neighborhood in Rio de Janeiro. A total of 2,816 mosquito larvae and pupae was collected, with an average of 5.87 immatures per plant per collection. Culex (Microculex) pleuristriatus and Culex spp of the Ocellatus Group were the most abundant culicid species, found in all species of bromeliads; next in relative abundance were species of the genus Wyeomyia. Only two individuals of Ae. aegypti (0.07%) and five of Ae. albopictus (0.18%) were collected from bromeliads. By contrast, immatures of Ae. aegypti were found in manmade containers in nearly 5% of nearby houses. These results demonstrate that bromeliads are not important producers of Ae. aegypti and Ae. albopictus and, hence, should not be a focus for dengue control. However, the results of this study of only one year in a single area may not represent outcomes in other urban localities where bromeliads, Ae. aegypti and dengue coincide in more disturbed habitats. PMID:20140379

  9. Multicountry prospective clinical evaluation of two enzyme-linked immunosorbent assays and two rapid diagnostic tests for diagnosing dengue Fever.

    PubMed

    Pal, Subhamoy; Dauner, Allison L; Valks, Andrea; Forshey, Brett M; Long, Kanya C; Thaisomboonsuk, Butsaya; Sierra, Gloria; Picos, Victor; Talmage, Sara; Morrison, Amy C; Halsey, Eric S; Comach, Guillermo; Yasuda, Chadwick; Loeffelholz, Michael; Jarman, Richard G; Fernandez, Stefan; An, Ung Sam; Kochel, Tadeusz J; Jasper, Louis E; Wu, Shuenn-Jue L

    2015-04-01

    We evaluated four dengue diagnostic devices from Alere, including the SD Bioline Dengue Duo (nonstructural [NS] 1 Ag and IgG/IgM), the Panbio Dengue Duo Cassette (IgM/IgG) rapid diagnostic tests (RDTs), and the Panbio dengue IgM and IgG capture enzyme-linked immunosorbent assays (ELISAs) in a prospective, controlled, multicenter study in Peru, Venezuela, Cambodia, and the United States, using samples from 1,021 febrile individuals. Archived, well-characterized samples from an additional 135 febrile individuals from Thailand were also used. Reference testing was performed on all samples using an algorithm involving virus isolation, in-house IgM and IgG capture ELISAs, and plaque reduction neutralization tests (PRNT) to determine the infection status of the individual. The primary endpoints were the clinical sensitivities and specificities of these devices. The SD Bioline Dengue Duo had an overall sensitivity of 87.3% (95% confidence interval [CI], 84.1 to 90.2%) and specificity of 86.8% (95% CI, 83.9 to 89.3%) during the first 14 days post-symptom onset (p.s.o.). The Panbio Dengue Duo Cassette demonstrated a sensitivity of 92.1% (87.8 to 95.2%) and specificity of 62.2% (54.5 to 69.5%) during days 4 to 14 p.s.o. The Panbio IgM capture ELISA had a sensitivity of 87.6% (82.7 to 91.4%) and specificity of 88.1% (82.2 to 92.6%) during days 4 to 14 p.s.o. Finally, the Panbio IgG capture ELISA had a sensitivity of 69.6% (62.1 to 76.4%) and a specificity of 88.4% (82.6 to 92.8%) during days 4 to 14 p.s.o. for identification of secondary dengue infections. This multicountry prospective study resulted in reliable real-world performance data that will facilitate data-driven laboratory test choices for managing patient care during dengue outbreaks. PMID:25588659

  10. CORRELATION OF SERUM LEVELS OF MACROPHAGE MIGRATION INHIBITORY FACTOR WITH DISEASE SEVERITY AND CLINICAL OUTCOME IN DENGUE PATIENTS

    Microsoft Academic Search

    LIEN-CHENG CHEN; HUAN-YAO LEI; CHING-CHUAN LIU; SHU-CHU SHIESH; SHUN-HUA CHEN; HSIAO-SHENG LIU; YEE-SHIN LIN; SHAN-TAIR WANG; HUEY-WEN SHYU; TRAI-MING YEH

    2006-01-01

    Dengue virus infection can cause mild dengue fever (DF) or severe dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS). Cytokines are believed to be involved in the pathogenesis of dengue infection. However, the role of the pro-inflammatory cytokine macrophage migration inhibitory factor (MIF) in dengue infection is unclear. In this study, serum levels of MIF in adult dengue patients

  11. Dengue and its effects on liver

    PubMed Central

    Samanta, Jayanta; Sharma, Vishal

    2015-01-01

    Dengue has emerged as an important arboviral disease with significant impact on the disease burden in population residing in tropical countries. Dengue is spread by the bite of Aedes mosquito. The virus seems to have some hepatotoxic effects. Affliction of liver in form of derangements in the liver function tests is common and may include mild elevations in serum bilirubin, elevated transaminases and derangements in serum albumin. Although asymptomatic in most cases, clinical manifestations like jaundice, and acute liver failure (ALF) may occasionally complicate the clinical picture. Indeed, dengue has been implicated as an important cause of ALF in endemic countries. The present review focuses on the hepatic manifestations and the pathogenesis of the liver injury in dengue. PMID:25685758

  12. Nosocomial RSV infection control and outbreak management.

    PubMed

    Bont, Louis

    2009-06-01

    The incidence of nosocomial respiratory syncytial virus (RSV) infection in different areas of the world is not well known. However, it is clear that RSV infection of hospitalized infants with congenital heart disease or following preterm birth is highly relevant. Nosocomial RSV infection in these high-risk group infants often follows a severe course of disease, even resulting in mortality. Transmission of RSV mainly occurs through direct contact, but not through inhalation. Consequently, prevention of nosocomial RSV infection should aim to prevent direct contact between non-infected infants and RSV-infected people. Evidence of the role of gowns, masks and gloves is discussed. The effect and safety of cohorting RSV-infected infants is reviewed. International guidelines with respect to RSV prevention and outbreak management are analysed. PMID:19651394

  13. Lung in Dengue: Computed Tomography Findings

    PubMed Central

    Rodrigues, Rosana Souza; Brum, Ana Livia Garcia; Paes, Marciano Viana; Póvoa, Tiago Fajardo; Basilio-de-Oliveira, Carlos Alberto; Marchiori, Edson; Borghi, Danielle Provençano; Ramos, Grazielle Viana; Bozza, Fernando Augusto

    2014-01-01

    Background Dengue is the most important mosquito-borne viral disease in the world. Dengue virus infection may be asymptomatic or lead to undifferentiated fever, dengue fever with or without warning signs, or severe dengue. Lower respiratory symptoms are unusual and lung-imaging data in patients with dengue are scarce. Methodology/Principal Findings To evaluate lung changes associated with dengue infection, we retrospectively analyzed 2,020 confirmed cases of dengue. Twenty-nine of these patients (11 females and 18 males aged 16–90 years) underwent chest computed tomography (CT), which yielded abnormal findings in 17 patients: 16 patients had pleural effusion (the sole finding in six patients) and 11 patients had pulmonary abnormalities. Lung parenchyma involvement ranged from subtle to moderate unilateral and bilateral abnormalities. The most common finding was ground-glass opacity in eight patients, followed by consolidation in six patients. Less common findings were airspace nodules (two patients), interlobular septal thickening (two patients), and peribronchovascular interstitial thickening (one patient). Lung histopathological findings in four fatal cases showed thickening of the alveolar septa, hemorrhage, and interstitial edema. Conclusions/Significance In this largest series involving the use of chest CT to evaluate lung involvement in patients with dengue, CT findings of lower respiratory tract involvement were uncommon. When abnormalities were present, pleural effusion was the most frequent finding and lung involvement was often mild or moderate and bilateral. Extensive lung abnormalities are infrequent even in severe disease and when present should lead physicians to consider other diagnostic possibilities. PMID:24836605

  14. School Meal Programs: Few Outbreaks of Foodborne Illness Reported. Report to the Ranking Minority Member, Committee on Agriculture, Nutrition, and Forestry, U.S. Senate.

    ERIC Educational Resources Information Center

    Robertson, Robert E.

    Twenty outbreaks of foodborne illness in schools were reported to the Centers for Disease Control and Prevention (CDC) during 1997; however, only 8 cases were associated with food served in the school meal programs. Preliminary findings identified nine outbreaks in 1998, affecting an estimated 1,609 individuals. CDC notes that such outbreaks are…

  15. Dengue fever: new paradigms for a changing epidemiology.

    PubMed

    Guha-Sapir, Debarati; Schimmer, Barbara

    2005-03-01

    Dengue is the most important arthropod-borne viral disease of public health significance. Compared with nine reporting countries in the 1950s, today the geographic distribution includes more than 100 countries worldwide. Many of these had not reported dengue for 20 or more years and several have no known history of the disease. The World Health Organization estimates that more than 2.5 billion people are at risk of dengue infection. First recognised in the 1950s, it has become a leading cause of child mortality in several Asian and South American countries.This paper reviews the changing epidemiology of the disease, focusing on host and societal factors and drawing on national and regional journals as well as international publications. It does not include vaccine and vector issues. We have selected areas where the literature raises challenges to prevailing views and those that are key for improved service delivery in poor countries.Shifts in modal age, rural spread, and social and biological determinants of race- and sex-related susceptibility have major implications for health services. Behavioural risk factors, individual determinants of outcome and leading indicators of severe illness are poorly understood, compromising effectiveness of control programmes. Early detection and case management practices were noted as a critical factor for survival. Inadequacy of sound statistical methods compromised conclusions on case fatality or disease-specific mortality rates, especially since the data were often based on hospitalised patients who actively sought care in tertiary centres.Well-targeted operational research, such as population-based epidemiological studies with clear operational objectives, is urgently needed to make progress in control and prevention. PMID:15743532

  16. Probing functional polymorphisms in the dengue vector, Aedes aegypti

    PubMed Central

    2013-01-01

    Background Dengue is the most prevalent arboviral disease world-wide and its primary vector is the mosquito Aedes aegypti. The current lack of commercially-available vaccines makes control of vector populations the only effective strategy to prevent dengue transmission. Aedes aegypti geographic populations exhibit great variability in insecticide resistance and susceptibility to dengue infection. The characterization of single nucleotide polymorphisms (SNPs) as molecular markers to study quantitatively this variation is needed greatly because this species has a low abundance of microsatellite markers and limited known restriction fragments length polymorphisms (RFLPs) and single-strand conformation polymorphism (SSCP) markers. Results We used RNA-seq to characterize SNPs in three Ae. aegypti strains, including the Liverpool (LVP) strain, from which the current genome annotation is derived. We identified 131,764 unique genome locations with at least one alternative nucleotide to what is reported in the reference annotation. These comprised changes in both open-reading frames (ORFs) and untranslated regions (UTRs) of transcripts. An in depth-look at sequence variation in immunity genes revealed that those associated with autophagy, MD2-like receptors and Peptidoglycan Recognition Proteins had more sequence variation in their 3’UTRs than mutations associated with non-synonymous changes. This supports the conclusion that these genes had maintained their functional specificity while being adapted to different regulatory domains. In contrast, a number of peroxidases, serpins and Clip-domain serine proteases exhibited conservation of putative UTR regulatory sequences while displaying diversification of the ORFs. Transcriptome evidence also was found for ~2500 novel transcriptional units (NTUs) not annotated in the reference genome. Conclusions The transcriptome-wide assessment of within and inter-strain polymorphisms in Ae. aegypti adds considerably to the number of molecular markers available for genetic studies in this mosquito. Additionally, data supporting NTU discovery emphasizes the need for continuous amendments of the reference genome annotation. PMID:24168143

  17. Successful use of N-acetyl cysteine and activated recombinant factor VII in fulminant hepatic failure and massive bleeding secondary to dengue hemorrhagic fever.

    PubMed

    Manoj, Edirisooriya Maddumage; Ranasinghe, Gayan; Ragunathan, M K

    2014-10-01

    Consensus on management of complicated cases of dengue infection is evolving. Dengue hemorrhagic fever (DHF) occasionally progress to fulminant liver failure with high fatality rate. Inadvertent use of blood products to control massive bleeding in dengue shock syndrome may worsen fluid overload and subsequently the multi-organ dysfunction. We report a case of 37-years-old Sri Lankan man who developed fulminant liver failure and massive bleeding associated with DHF, subsequently recovered completely with supportive measures including administration of N-acetyl cysteine and activated recombinant factor VII. In conclusion, prevention of ischemic injury to liver and adoption of early aggressive supportive measures in complicated cases of dengue hemorrhagic fever is crucial for a favorable outcome. Indications for rFVIIa to arrest uncontrolled internal bleeding and use of NAC in non-acetaminophen-induced acute liver failure in complicated DHF are a platform for discussion. PMID:25400395

  18. Seropositivity of Dengue Antibodies during Pregnancy

    PubMed Central

    Mohamed Ismail, Nor Azlin; Wan Abd Rahim, Wan Elly Rushima; Salleh, Sharifah Azura; Neoh, Hui-Min; Jamal, Rahman; Jamil, Muhammad Abdul

    2014-01-01

    Purpose. Malaysia a dengue endemic country with dengue infections in pregnancy on the rise. The present study was aimed at determining dengue seroprevalence (IgG or IgM) during pregnancy and its neonatal transmission in dengue seropositive women. Methods. Maternal with paired cord blood samples were tested for dengue antibodies (IgG and IgM) using an enzyme-linked immunosorbent assay (ELISA). Maternal age, parity, occupation, ethnic group, and gestational age were recorded. Data on neonatal Apgar score and admissions to the Neonatal Intensive Care Unit (NICU) were analyzed. Results. Out of 358 women recruited, about 128 (35.8%) patients were seropositive. Twelve patients (3.4%) had recent infections (IgM positive) and another 116 women (32.4%) were with past infections (IgG positive). All babies born to seropositive mothers had positive IgG paired cord blood; however, no IgM seropositivity was observed. All neonates had good Apgar scores and did not require NICU admission. Conclusion. In this study, 35.8% pregnant women were found to be dengue seropositive. However, transplacental transfer of IgG antibodies had no detrimental effect on the neonatal outcomes. PMID:25587564

  19. Antioxidants in patients with dengue viral infection.

    PubMed

    Chandrasena, Lal G; Peiris, Hemantha; Kamani, J; Wanigasuriya, P; Jayaratne, Shantilal D; Wijayasiri, W A A; Wijesekara, G Udaya S

    2014-09-01

    An alteration in the oxidation/reduction (redox) status of humans infected with virus infections may contrioute to tefl pariiogeiiesin anu ciniiua1 manifestations of the disease. Alterations in redox markers begin prior to the onset of clinical symptoms, suggesting early changes in the oxidant/antioxidant balance. Early identification of redox markers may be of clinical usefulness in the management of patients with dengue virus infection. We conducted a hospital based comparative cross sectional study of 55 patients serologically confirmed to have dengue infection and 55 clinically healthy age and sex matched subjects as controls to assess oxidative stress in acute dengue virus infection. Blood samples were drawn on the fifth day after symptom onset and analyzed for Trolox equivalent antioxidant capacity (TEAC), reduced glutathione (GSH), glutathione peroxidase (GPx) and paraoxonase (PON) activity. The results showed significantly lower levels of plasma TEAC, serum PON and erythrocyte GSH and GPx activity among dengue patients than in controls. Of the antioxidants investigated, PON appeared to be the most sensitive marker of oxidative stress in dengue virus infection. Serum PON may be a potentially useful marker of oxidative stress in patients with dengue virus infection. PMID:25417502

  20. Antioxidants in patients with dengue viral infection.

    PubMed

    Chandrasena, Lal G; Peiris, Hemantha; Kamani, J; Wanigasuriya, P; Jayaratne, Shantilal D; Wijayasiri, W A A; Wijesekara, G Udaya S

    2014-09-01

    An alteration in the oxidation/reduction (redox) status of humans infected with virus infections may contrioute to tefl pariiogeiiesin anu ciniiua1 manifestations of the disease. Alterations in redox markers begin prior to the onset of clinical symptoms, suggesting early changes in the oxidant/antioxidant balance. Early identification of redox markers may be of clinical usefulness in the management of patients with dengue virus infection. We conducted a hospital based comparative cross sectional study of 55 patients serologically confirmed to have dengue infection and 55 clinically healthy age and sex matched subjects as controls to assess oxidative stress in acute dengue virus infection. Blood samples were drawn on the fifth day after symptom onset and analyzed for Trolox equivalent antioxidant capacity (TEAC), reduced glutathione (GSH), glutathione peroxidase (GPx) and paraoxonase (PON) activity. The results showed significantly lower levels of plasma TEAC, serum PON and erythrocyte GSH and GPx activity among dengue patients than in controls. Of the antioxidants investigated, PON appeared to be the most sensitive marker of oxidative stress in dengue virus infection. Serum PON may be a potentially useful marker of oxidative stress in patients with dengue virus infection. PMID:25507230

  1. Wild Animal Mortality Monitoring and Human Ebola Outbreaks, Gabon and Republic of Congo, 2001–2003

    PubMed Central

    Froment, Jean-Marc; Bermejo, Magdalena; Kilbourn, Annelisa; Karesh, William; Reed, Patricia; Kumulungui, Brice; Yaba, Philippe; Délicat, André; Rollin, Pierre E.; Leroy, Eric M.

    2005-01-01

    All human Ebola virus outbreaks during 2001–2003 in the forest zone between Gabon and Republic of Congo resulted from handling infected wild animal carcasses. After the first outbreak, we created an Animal Mortality Monitoring Network in collaboration with the Gabonese and Congolese Ministries of Forestry and Environment and wildlife organizations (Wildlife Conservation Society and Programme de Conservation et Utilisation Rationnelle des Ecosystèmes Forestiers en Afrique Centrale) to predict and possibly prevent human Ebola outbreaks. Since August 2001, 98 wild animal carcasses have been recovered by the network, including 65 great apes. Analysis of 21 carcasses found that 10 gorillas, 3 chimpanzees, and 1 duiker tested positive for Ebola virus. Wild animal outbreaks began before each of the 5 human Ebola outbreaks. Twice we alerted the health authorities to an imminent risk for human outbreaks, weeks before they occurred. PMID:15752448

  2. Surveillance for Waterborne Disease Outbreaks Associated with Drinking Water United States, 2007-2008

    EPA Science Inventory

    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...

  3. Nosocomial Influenza outbreak in an intensive-care unit

    Microsoft Academic Search

    V Jacomo; C Sartor; C Zandotti; C Atlan-Gepner; M Drancourt

    2001-01-01

    Objective – The authors investigated a nosocomial outbreak of pneumonia to determine the etiological diagnosis, to evaluate the transmission route, the modalities of prevention, and the cost.Methods – All patients and staff members present in this acute-care unit had nasal wash, pharyngeal sampling and serological testing for detection of pneumonia agents. Epidemiological variables studied included influenza like illness, underlying disease

  4. Gastroenteritis Outbreak Associated with Unpasteurized Tempeh, North Carolina, USA

    PubMed Central

    Fleischauer, Aaron T.; MacFarquhar, Jennifer K.; Moore, Zackary; Harrelson, Cris; Valiani, Anita; Morrison, Sue Ellen; Sweat, David; Maillard, Jean-Marie; Griffin, Denise; Springer, Debra; Mikoleit, Matthew; Newton, Anna E.; Jackson, Brendan; Nguyen, Thai-An; Bosch, Stacey; Davies, Megan

    2013-01-01

    During an investigation of an outbreak of gastroenteritis caused by Salmonella enterica serovar Paratyphi B variant L(+) tartrate(+), we identified unpasteurized tempeh as a novel food vehicle and Rhizopus spp. starter culture as the source of the contamination. Safe handling of uncooked, unpasteurized tempeh should be emphasized for prevention of foodborne illnesses. PMID:23965530

  5. Frequency and Clinical Manifestations of Dengue in Urban Medellin, Colombia

    PubMed Central

    Restrepo, Berta Nelly; Beatty, Mark E.; Goez, Yenny; Ramirez, Ruth E.; Letson, G. William; Diaz, Francisco J.; Piedrahita, Leidy Diana; Osorio, Jorge E.

    2014-01-01

    A dengue fever surveillance study was conducted at three medical facilities located in the low-income district of San Javier in Medellin, Colombia. During March 2008 to 2009, 781 patients with fever regardless of chief complaint were recruited for acute dengue virus infection testing. Of the 781 tested, 73 (9.3%) were positive for dengue infection. Serotypes DENV-2 (77%) and -3 (23%) were detected by PCR. One patient met the diagnostic criteria for dengue hemorrhagic fever. Only 3 out of 73 (4.1%) febrile subjects testing positive for dengue infection were diagnosed with dengue fever by the treating physician. This study confirms dengue virus as an important cause of acute febrile illness in Medellin, Colombia, but it is difficult to diagnose without dengue diagnostic testing. PMID:24987421

  6. Hypokalemic quadriparesis: An unusual manifestation of dengue fever

    PubMed Central

    Gutch, Manish; Agarwal, Avinash; Amar, Amrendra

    2012-01-01

    Dengue is the most important mosquito-borne, arboviral infection found in tropical and sub-tropical climates. Clinical presentation varies from a severe flu-like illness to a potentially lethal dengue hemorrhagic fever. Dengue has been regarded as a nonneurotropic virus. However, there are reports describing neurological involvements in dengue virus infection. The neurological involvement in dengue virus infection includes encephalitis, acute disseminated encephalomyelitis, transverse myelitis, and Guillain-Barre syndrome. The neurological spectrum of dengue patients has been limited because of small number of case reports, paucity of imaging, and neurophysiologic studies. There are only a few isolated case reports and case series documenting acute pure motor quadriparesis in dengue fever. We report acute pure motor reversible quadriparesis due to hypokalemia. Clinicians in the endemic area should be aware of such association of acute pure motor reversible quadriparesis with dengue fever PMID:22690057

  7. [Lessons learned from tuberculosis outbreak cases].

    PubMed

    Kato, Seiya; Kuwabara, Katsuhiro

    2014-02-01

    Most TB outbreaks were caused by exposure of many people to tuberculosis bacilli due to delayed detection of initial cases who had long-lasting severe coughs and excretion of massive tuberculosis bacilli. They were also affected by several other factors, such as socio-environmental factors of the initial case; time and place of infection; and host factors of the infected persons such as immune status, infectivity, and/or pathogenicity of the bacilli. In this symposium, we learned the seriousness of infection and disease among immune-suppressed groups, special environmental factors with regard to the spread of infection, disease after treatment of latent tuberculosis infection, diagnostic specification of IGRA, and bacteriological features including genotyping of the bacilli. We reaffirmed that countermeasures for the case are important, but outbreaks can provide excellent opportunities to learn important information about infection, disease progression, etc. 1. Tuberculosis outbreak in a cancer ward: Katsuhiro KUWABARA (Division of Respiratory Diseases, National Hospital Organization Nishi-Niigata Chuo National Hospital) There was an outbreak of tuberculosis in a cancer ward of a highly specialized medical center. Outbreak cases included eight hospitalized patients and two medical staff members over a 1.5-year observation period after initial contact. Three immune-compromised patients including the index patent died of cancer and tuberculosis. Community hospitals and highly specialized medical centers, such as cancer centers, should carefully prepare a proper system to prevent nosocomial transmission of tuberculosis. 2. Sixty-one cases of TB exposures in hospital settings and contact investigations of the hospital staff, with special reference to the application of QFT: Hiroko Yoshikawa NIGORIKAWA (The Division of Infectious Diseases, Tokyo Metropolitan Health and Medical Treatment Corporation, Toshima Hospital; present: Division of Infectious Diseases, Tokyo Teishin Hospital), Toru MORI (Research Institute of Tuberculosis, Japan Anti-Tuberculosis Association) The index case was a patient who was admitted to a general hospital where she was treated with pulsed corticosteroid therapy and then put on a respirator. Soon after, she developed tuberculosis (TB) and died. Immediately after her death, the healthcare workers who had close contact with the index case were given the QuantiFERON TB Gold (QFT) test, which indicated that all staff except one were negative. However, a QFT test administered eight weeks later had a positive rate of 18.6%. Subsequently, a total of five workers, including a doctor, nurses, and radiology technicians, developed TB. The bacterial isolates from five of them exhibited an RFLP pattern identical to that of the index case. These secondary cases of TB included a case who had contact of less than 5 minutes, a case whose QFT was negative ("doubtful" in the Japanese criterion of the QFT), and a case who was QFT-positive but declined to be treated for latent TB infection (LTBI). No other workers nor hospitalized patients developed TB. The healthcare worker contacts were further examined with the QFT 6, 9 and 12 months after the contact. The QFT results revealed four additional positive reactors and four "doubtful" reactors who were indicated for LTBI treatment. Among them were seven subjects who turned positive six months after the contact. TB prevention in hospital settings and contact investigations were discussed with the hospital staff, with special reference to the application of QFT. 3. Summary and issues of concern relating to a tuberculosis outbreak in a prison: Mitsunobu HOMMA, Takefumi ITOH (Department of Respiratory Medicine, Akita City Hospital) We report a tuberculosis outbreak that occurred in a prison in the spring of 2011, resulting in 11 cases of active disease and 40 cases of infection. The primary cause of the outbreak is thought to be the delay in identifying the index case, where the screening result interpretation might have contributed to the delay. However, w

  8. A model for the spatial transmission of dengue with daily movement between villages and a city.

    PubMed

    Nevai, Andrew L; Soewono, Edy

    2014-06-01

    Dengue is a re-emergent vector-borne disease affecting large portions of the world's population living in the tropics and subtropics. The virus is transmitted through the bites of female Aedes aegypti mosquitoes, and it is widely believed that these bites occur primarily in the daytime. The transmission of dengue is a complicated process, and one of the main sources of this complexity is due to the movement of people, e.g. between home and their places of work. Hence, the mechanics of disease progression may also differ between day and night. A discrete-time multi-patch dengue transmission model which takes into account the mobility of people as well as processes of infection, recovery, recruitment, mortality, and outbound and return movements is considered here. One patch (the city) is connected to all other patches (the villages) in a spoke-like network. We obtain here the basic reproductive ratio (?0) of the transmission model which represents a threshold for an epidemic to occur. Dynamical analysis for vector control, human treatment and vaccination, and different kinds of mobility are performed. It is shown that changes in human movement patterns can, in some situations, affect the ability of the disease to persist in a predictable manner. We conclude with biological implications for the prevention and control of dengue virus transmission. PMID:23475426

  9. Pathogenic Roles of Macrophage Migration Inhibitory Factor during Dengue Virus Infection

    PubMed Central

    Chuang, Yung-Chun; Chen, Hong-Ru

    2015-01-01

    Dengue virus (DENV) infection is the most common cause of viral hemorrhagic fever, which can lead to life-threatening dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS). Hemorrhage and plasma leakage are two major hallmarks of DHF/DSS. Because the mechanisms causing these pathogenic changes are unclear, there is no effective therapy against DHF/DSS. In this review, we focus on the possible pathogenic effects of a pleiotropic cytokine, macrophage migration inhibitory factor (MIF), on the pathogenesis of DENV infection. MIF is a critical mediator of the host immune response and inflammation, and there is a correlation between the serum levels of MIF and disease severity in dengue patients. Furthermore, MIF knock-out mice exhibit less severe clinical disease and lethality. However, the role of MIF in the pathogenesis of DHF/DSS is not limited to immune cell recruitment. Recent evidence indicates that DENV infection induced MIF production and may contribute to vascular hyperpermeability and viral replication during DENV infection. The expression of both adhesion and coagulation molecules on MIF-stimulated monocytes and endothelial cells is also increased, which may contribute to inflammatory and anticoagulatory states during DHF/DSS. Therefore, blocking MIF production or its function may provide a solution for the treatment and prevention of DHF/DSS. PMID:25821355

  10. Disease mapping based on stochastic SIR-SI model for Dengue and Chikungunya in Malaysia

    NASA Astrophysics Data System (ADS)

    Samat, N. A.; Ma'arof, S. H. Mohd Imam

    2014-12-01

    This paper describes and demonstrates a method for relative risk estimation which is based on the stochastic SIR-SI vector-borne infectious disease transmission model specifically for Dengue and Chikungunya diseases in Malaysia. Firstly, the common compartmental model for vector-borne infectious disease transmission called the SIR-SI model (susceptible-infective-recovered for human populations; susceptible-infective for vector populations) is presented. This is followed by the explanations on the stochastic SIR-SI model which involve the Bayesian description. This stochastic model then is used in the relative risk formulation in order to obtain the posterior relative risk estimation. Then, this relative estimation model is demonstrated using Dengue and Chikungunya data of Malaysia. The viruses of these diseases are transmitted by the same type of female vector mosquito named Aedes Aegypti and Aedes Albopictus. Finally, the findings of the analysis of relative risk estimation for both Dengue and Chikungunya diseases are presented, compared and displayed in graphs and maps. The distribution from risk maps show the high and low risk area of Dengue and Chikungunya diseases occurrence. This map can be used as a tool for the prevention and control strategies for both diseases.

  11. A Systematic Review and Meta-Analysis of Dengue Risk with Temperature Change

    PubMed Central

    Fan, Jingchun; Wei, Wanxia; Bai, Zhenggang; Fan, Chunling; Li, Shulan; Liu, Qiyong; Yang, Kehu

    2014-01-01

    Dengue fever (DF) is the most serious mosquito-borne viral disease in the world and is significantly affected by temperature. Although associations between DF and temperatures have been reported repeatedly, conclusions have been inconsistent. Six databases were searched up to 23 March 2014, without language and geographical restrictions. The articles that studied the correlations between temperatures and dengue were selected, and a random-effects model was used to calculate the pooled odds ratio and 95% confidence intervals. Of 1589 identified articles, 137 were reviewed further, with 33 satisfying inclusion criteria. The closest associations were observed between mean temperature from the included studies (23.2–27.7 °C) and DF (OR 35.0% per 1 °C; 95% CI 18.3%–51.6%) positively. Additionally, minimum (18.1–24.2 °C) (29.5% per 1 °C; 20.9%–38.1%) and maximum temperature (28.0–34.5 °C) (28.9%; 10.3%–47.5%) were also associated with increased dengue transmission. The OR of DF incidence increased steeply from 22 °C to 29 °C, suggesting an inflexion of DF risk between these lower and upper limits of DF risk. This discovery is helpful for government decision-makers focused on preventing and controlling dengue in areas with temperatures within this range. PMID:25546270

  12. Connecting Environmental Observations with Cholera Outbreaks in Bangladesh

    NASA Astrophysics Data System (ADS)

    Stack, D.; Sandborn, A.; Widmeyer, P. A.; Escobar, V. M.

    2011-12-01

    Research has demonstrated that cholera epidemics in Bangladesh occur seasonally. This bimodal outbreak pattern closely follows times when large monsoon events are most frequent (spring and fall). While these patterns are presented in regional data, this knowledge alone cannot forecast the severity and location of cholera outbreaks until a monsoon event occurs, or an outbreak is reported. Therefore, there can only be reactive responses to cholera outbreaks. A heightened understanding of the link between environmental factors and outbreak occurrence will greatly enhance disease management capabilities. A predictive tool capable of giving an advanced warning of the environmental hazards that lead to location specific outbreaks allows for proactive and preventative responses, minimizing negative effects. A specific goal of this research was to relate latitude-longitude data with existing points associated with V. cholerae human case data collected from four cities in Bangladesh. Remotely sensed products were used to better understand the correlation between human outbreak occurrences, chlorophyll-a estimates, sea surface temperature (SST), and rainfall. Using MODIS, SeaWiFS, and TRMM satellite data, a gridded regional image was developed. Correlation analyses of the data were studied within the context of geographically diverse locations for the four cities of interest. Seasonal relationships were found between the cholera case data and all three of the chosen remotely sensed parameters. The strongest correlation found was between chlorophyll-a concentrations and reported human cases. The primary deliverable of this project was the production of an interactive Google Earth base map for use in a pilot design study that will lead to the development of applications to connect earth science products with water and health studies. The base map, with its inherent value of merging remotely sensed data with in situ observation points, can be used as a basis for constructing better models of disease outbreaks. This effort will build upon current research at University of Maryland, College Park, which focuses on the impacts of climate on both water and health.

  13. Impact of Drainage Networks on Cholera Outbreaks in Lusaka, Zambia

    PubMed Central

    Suzuki, Hiroshi; Fujino, Yasuyuki; Kimura, Yoshinari; Cheelo, Meetwell

    2009-01-01

    Objectives. We investigated the association between precipitation patterns and cholera outbreaks and the preventative roles of drainage networks against outbreaks in Lusaka, Zambia. Methods. We collected data on 6542 registered cholera patients in the 2003–2004 outbreak season and on 6045 cholera patients in the 2005–2006 season. Correlations between monthly cholera incidences and amount of precipitation were examined. The distribution pattern of the disease was analyzed by a kriging spatial analysis method. We analyzed cholera case distribution and spatiotemporal cluster by using 2590 cholera cases traced with a global positioning system in the 2005–2006 season. The association between drainage networks and cholera cases was analyzed with regression analysis. Results. Increased precipitation was associated with the occurrence of cholera outbreaks, and insufficient drainage networks were statistically associated with cholera incidences. Conclusions. Insufficient coverage of drainage networks elevated the risk of cholera outbreaks. Integrated development is required to upgrade high-risk areas with sufficient infrastructure for a long-term cholera prevention strategy. PMID:19762668

  14. Serological markers during dengue 3 primary and secondary infections

    Microsoft Academic Search

    S. Vázquez; A. B. Pérez; D. Ruiz; R. Rodríguez; M. Pupo; N. Calzada; L. González; D. González; O. Castro; T. Serrano; M. G. Guzmán

    2005-01-01

    Background:The detection of the IgM antibody for the dengue virus in serum by ELISA has become one of the most important and useful methods for diagnosis of dengue using a single acute-phase serum sample. Currently, this system is an invaluable tool for the surveillance of dengue fever (DF) and dengue hemorrhagic fever (DHF). The usefulness of other serological markers such

  15. Predicting Local Dengue Transmission in Guangzhou, China, through the Influence of Imported Cases, Mosquito Density and Climate Variability

    PubMed Central

    Sang, Shaowei; Yin, Wenwu; Bi, Peng; Zhang, Honglong; Wang, Chenggang; Liu, Xiaobo; Chen, Bin; Yang, Weizhong; Liu, Qiyong

    2014-01-01

    Introduction Each year there are approximately 390 million dengue infections worldwide. Weather variables have a significant impact on the transmission of Dengue Fever (DF), a mosquito borne viral disease. DF in mainland China is characterized as an imported disease. Hence it is necessary to explore the roles of imported cases, mosquito density and climate variability in dengue transmission in China. The study was to identify the relationship between dengue occurrence and possible risk factors and to develop a predicting model for dengue’s control and prevention purpose. Methodology and Principal Findings Three traditional suburbs and one district with an international airport in Guangzhou city were selected as the study areas. Autocorrelation and cross-correlation analysis were used to perform univariate analysis to identify possible risk factors, with relevant lagged effects, associated with local dengue cases. Principal component analysis (PCA) was applied to extract principal components and PCA score was used to represent the original variables to reduce multi-collinearity. Combining the univariate analysis and prior knowledge, time-series Poisson regression analysis was conducted to quantify the relationship between weather variables, Breteau Index, imported DF cases and the local dengue transmission in Guangzhou, China. The goodness-of-fit of the constructed model was determined by pseudo-R2, Akaike information criterion (AIC) and residual test. There were a total of 707 notified local DF cases from March 2006 to December 2012, with a seasonal distribution from August to November. There were a total of 65 notified imported DF cases from 20 countries, with forty-six cases (70.8%) imported from Southeast Asia. The model showed that local DF cases were positively associated with mosquito density, imported cases, temperature, precipitation, vapour pressure and minimum relative humidity, whilst being negatively associated with air pressure, with different time lags. Conclusions Imported DF cases and mosquito density play a critical role in local DF transmission, together with weather variables. The establishment of an early warning system, using existing surveillance datasets will help to control and prevent dengue in Guangzhou, China. PMID:25019967

  16. Disease Outbreaks Caused by Water.

    ERIC Educational Resources Information Center

    Craun, Gunther F.

    1978-01-01

    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)

  17. INVESTIGATIONS OF WATERBORNE DISEASE OUTBREAKS

    EPA Science Inventory

    From 1971-2000, there were about 751 waterborne disease outbreaks recognized and reported, with over 500,000 associated cases of illness. From 1989-1994, of 90 total outbreaks, 2% were associated with untreated surface water, 30% with untreated ground water, 42% with treatment de...

  18. RESEARCH Open Access Detection of dengue group viruses by

    E-print Network

    Boyer, Edmond

    virus or yellow fever virus. The same protocol was used on salivary glands of Ae. albopictus fed and Patrick Mavingui1* Abstract Background: Dengue fever (DF) and dengue hemorrhagic fever (DHF) represent://www.parasitesandvectors.com/content/5/1/243 #12;Background Dengue fever (DF) is the most common arthropod-borne human viral disease

  19. Describing dengue epidemics: Insights from simple mechanistic models

    NASA Astrophysics Data System (ADS)

    Aguiar, Maíra; Stollenwerk, Nico; Kooi, Bob W.

    2012-09-01

    We present a set of nested models to be applied to dengue fever epidemiology. We perform a qualitative study in order to show how much complexity we really need to add into epidemiological models to be able to describe the fluctuations observed in empirical dengue hemorrhagic fever incidence data offering a promising perspective on inference of parameter values from dengue case notifications.

  20. Results from the First 12 Months of the National Surveillance of Healthcare Associated Outbreaks in Germany, 2011/2012

    PubMed Central

    Haller, Sebastian; Eckmanns, Tim; Benzler, Justus; Tolksdorf, Kristin; Claus, Hermann; Gilsdorf, Andreas; Sin, Muna Abu

    2014-01-01

    Background In August 2011, the German Protection against Infection Act was amended, mandating the reporting of healthcare associated infection (HAI) outbreak notifications by all healthcare workers in Germany via local public health authorities and federal states to the Robert Koch Institute (RKI). Objective To describe the reported HAI-outbreaks and the surveillance system’s structure and capabilities. Methods Information on each outbreak was collected using standard paper forms and notified to RKI. Notifications were screened daily and regularly analysed. Results Between November 2011 and November 2012, 1,326 paper forms notified 578 HAI-outbreaks, between 7 and 116 outbreaks per month. The main causative agent was norovirus (n?=?414/578; 72%). Among the 108 outbreaks caused by bacteria, the most frequent pathogens were Clostridium difficile (25%) Klebsiella spp. (19%) and Staphylococcus spp. (19%). Multidrug-resistant bacteria were responsible for 54/108 (50%) bacterial outbreaks. Hospitals were affected most frequently (485/578; 84%). Hospital outbreaks due to bacteria were mostly reported from intensive care units (ICUs) (45%), followed by internal medicine wards (16%). Conclusion The mandatory HAI-outbreak surveillance system describes common outbreaks. Pathogens with a particular high potential to cause large or severe outbreaks may be identified, enabling us to further focus research and preventive measures. Increasing the sensitivity and reliability of the data collection further will facilitate identification of outbreaks able to increase in size and severity, and guide specific control measures to interrupt their propagation. PMID:24875674

  1. Mumps Cases and Outbreaks

    MedlinePLUS

    ... Answers Disease Description Physical Findings and Complications Case Reporting Exposure and Response Prevention and Control in Healthcare Settings Background Acceptable Presumptive Evidence of ...

  2. Host and viral features of human dengue cases shape the population of infected and infectious Aedes aegypti mosquitoes

    PubMed Central

    Nguyen, Nguyet Minh; Thi Hue Kien, Duong; Tuan, Trung Vu; Quyen, Nguyen Than Ha; Tran, Chau N. B.; Vo Thi, Long; Thi, Dui Le; Nguyen, Hoa Lan; Farrar, Jeremy J.; Holmes, Edward C.; Rabaa, Maia A.; Bryant, Juliet E.; Nguyen, Truong Thanh; Nguyen, Huong Thi Cam; Nguyen, Lan Thi Hong; Pham, Mai Phuong; Nguyen, Hung The; Luong, Tai Thi Hue; Wills, Bridget; Nguyen, Chau Van Vinh; Wolbers, Marcel; Simmons, Cameron P.

    2013-01-01

    Dengue is the most prevalent arboviral disease of humans. The host and virus variables associated with dengue virus (DENV) transmission from symptomatic dengue cases (n = 208) to Aedes aegypti mosquitoes during 407 independent exposure events was defined. The 50% mosquito infectious dose for each of DENV-1–4 ranged from 6.29 to 7.52 log10 RNA copies/mL of plasma. Increasing day of illness, declining viremia, and rising antibody titers were independently associated with reduced risk of DENV transmission. High early DENV plasma viremia levels in patients were a marker of the duration of human infectiousness, and blood meals containing high concentrations of DENV were positively associated with the prevalence of infectious mosquitoes 14 d after blood feeding. Ambulatory dengue cases had lower viremia levels compared with hospitalized dengue cases but nonetheless at levels predicted to be infectious to mosquitoes. These data define serotype-specific viremia levels that vaccines or drugs must inhibit to prevent DENV transmission. PMID:23674683

  3. High household economic burden caused by hospitalization of patients with severe dengue fever cases in Can Tho province, Vietnam.

    PubMed

    Tam, Pham Thi; Dat, Nguyen Tan; Huu, Le Minh; Thi, Xuan Cuc Pham; Duc, Hoang Minh; Tu, Tran Cong; Kutcher, Simon; Ryan, Peter A; Kay, Brian H

    2012-09-01

    During 2006-2007, a cohort of 144 confirmed dengue cases in Can Tho Province, Vietnam were compared with a matching set of 144 households that had no dengue cases. Approximately 6-9 months after sickness, there were no significant differences in terms of knowledge of the etiology of dengue, mosquito breeding habitats, and prevention measures in respondents from both sets of households. There was also no difference in the abundance of Aedes aegypti (Linn.) adults but the average numbers of late instar and pupal Ae. aegypti per household were greater in the negative control houses. Thus, the risk seemed to be no higher in case households, although it is conceivable that changes may have occurred in either group over the intervening period. The average cost for a dengue patient was 2,798,000 Vietnamese Dong (VND) (US$167.77), 2,154,000 VND for direct costs, and 644,000 VND for indirect costs. There was a 22% difference in cost for those with and without health insurance. In terms of impact on family economies, 47.2% had to borrow money for treatment, and after 6 months, 71.7% had not begun or had only managed part repayments. Approximately 72.9% indicated that the cost of supporting a dengue patient had impacted on the family economy, with the loss averaging 36% of the annual income in the lowest economic quartile. PMID:22826478

  4. Carnival or football, is there a real risk for acquiring dengue fever in Brazil during holidays seasons?

    NASA Astrophysics Data System (ADS)

    Aguiar, Maíra; Rocha, Filipe; Pessanha, José Eduardo Marques; Mateus, Luis; Stollenwerk, Nico

    2015-02-01

    More than 600,000 football fans, coming from all over the world, were expected to visit Brazil during the FIFA World Cup 2014. International travel can become a public health problem when the visitors start to become sick, needing medical intervention and eventually hospitalization. The occurrence of dengue fever infections in Brazil is persistent and has been increasing since the 1980s, and the health authorities were expected to take preventive measures and to warn the visitors about the risks during the tournament period. Before the World Cup started, studies have been published stating that dengue could be a significant problem in some of the Brazilian cities hosting the games. These conclusions were taken after a brief observation of the available data, analyzing its mean and standard deviation only, or based on seasonal climate forecasts, causing alarm for the world cup in Brazil. Here, with a more careful data analysis, we show that the seasonality of the disease plays a major role in dengue transmission. The density of dengue cases in Brazil is residual during winter in the Southern hemisphere (mid June to mid September) and the fans of football were not likely to get dengue during the tournament period.

  5. Carnival or football, is there a real risk for acquiring dengue fever in Brazil during holidays seasons?

    PubMed

    Aguiar, Maíra; Rocha, Filipe; Pessanha, José Eduardo Marques; Mateus, Luis; Stollenwerk, Nico

    2015-01-01

    More than 600,000 football fans, coming from all over the world, were expected to visit Brazil during the FIFA World Cup 2014. International travel can become a public health problem when the visitors start to become sick, needing medical intervention and eventually hospitalization. The occurrence of dengue fever infections in Brazil is persistent and has been increasing since the 1980s, and the health authorities were expected to take preventive measures and to warn the visitors about the risks during the tournament period. Before the World Cup started, studies have been published stating that dengue could be a significant problem in some of the Brazilian cities hosting the games. These conclusions were taken after a brief observation of the available data, analyzing its mean and standard deviation only, or based on seasonal climate forecasts, causing alarm for the world cup in Brazil. Here, with a more careful data analysis, we show that the seasonality of the disease plays a major role in dengue transmission. The density of dengue cases in Brazil is residual during winter in the Southern hemisphere (mid June to mid September) and the fans of football were not likely to get dengue during the tournament period. PMID:25684648

  6. Dengue surveillance in the French armed forces: a dengue sentinel surveillance system in countries without efficient local epidemiological surveillance.

    PubMed

    de Laval, Franck; Dia, Aissata; Plumet, Sébastien; Decam, Christophe; Leparc Goffart, Isabelle; Deparis, Xavier

    2013-01-01

    Surveillance of travel-acquired dengue could improve dengue risk estimation in countries without ability. Surveillance in the French army in 2010 to 2011 highlighted 330 dengue cases, mainly in French West Indies and Guiana: DENV-1 circulated in Guadeloupe, Martinique, French Guiana, New Caledonia, Djibouti; DENV-3 in Mayotte and Djibouti; and DENV-4 in French Guiana. PMID:23809078

  7. [Dengue vector density survey in Liuchiu, Pintung, Taiwan].

    PubMed

    Lin, H M; Chen, C S; Hsu, C C; Chung, C L

    1986-08-01

    The first outbreak of dengue in Taiwan in 35 years was recorded in the summer of 1981 in Liuchiu, Pintung, a small offshore island of southern Taiwan. An investigation team visited the affected area during the period of 14-17 October 1981 and collected 8,641 mosquito larvae, of which 4,432 were Aedes aegypti and 4,182 were Ae. albopictus. The house index, container index and Breteau index were 44.2, 23.9 and 73.0 for Ae. aegypti and 41.3, 17.0 and 51.9 for Ae. albopictus, respectively. Both species of mosquitoes are peridomestic breeders, with larvae found in water-holding containers in or outside houses. Ae. albopictus is indigenous, but Ae. aegypti may be of recent introduction to the island. As the two species are closely related, the larvae of both species were found co-existent in only 2.3% of positive containers. This supports the hypothesis of the "competitive exclusion principle", i.e., competition is possibly occurring on this island. PMID:2880696

  8. 75 FR 58415 - Prospective Grant of Exclusive License: Prevention, Prophylaxis, Cure, Amelioration, and/or...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-24

    ...transmitted to humans by mosquitoes. The disease caused by CHIKV resembles infection by dengue virus, characterized by rash, high fever, and severe, sometimes persistent arthritis. The field of use may be limited to ``Prevention, prophylaxis, cure,...

  9. An outbreak of ornithosis.

    PubMed

    Jernelius, H; Pettersson, B; Schvarcz, J; Vahlne, A

    1975-01-01

    An outbreak of ornithosis occurred in Lidköping, a small town in Southwest Sweden, in January 1967 through May 1969. 24 proved cases were known, aged from 10 to 72 years, 19 patients gave a history of contact with birds (parrots, canaries, parakeets), 13 of them with birds from the same pet shop. Five patients had visited the pet shop only once before their illness. Attempts to prove infection with ornithosis agent in 7 birds from the pet shop were unsuccessful. Three patients, 2 of them in the same household, had no contact with birds and infection from person to person was strongly suspected. All patients had pneumonia. Fever, cough and headache were predominant clinical symptoms. There were relapses in 4 patients and 2 patients had symptoms of encephalitis. No deaths occurred. PMID:1237175

  10. Dengue Fever With Rectus Sheath Hematoma: A Case Report

    PubMed Central

    Sharma, Anurag; Bhatia, Sonia; Singh, Rajendra Pratap; Malik, Gaurav

    2014-01-01

    Dengue fever, also known as breakbone fever, is an infectious tropical disease caused by the Dengue virus. It is associated with a number of complications, which are well documented. However, Dengue fever associated with rectus sheath hematoma (RSH) is a very rare complication. Only one case report has been published prior supporting the association of Dengue fever with RSH. We report a case of Dengue fever who presented with RSH and was successfully treated conservatively. RSH is also an uncommon cause of acute abdominal pain. It is accumulation of blood in the sheath of the rectus abdominis, secondary to rupture of an epigastric vessel or muscle tear. PMID:25161976

  11. Developing a Vulnerability Mapping Methodology: Applying the Water-Associated Disease Index to Dengue in Malaysia

    PubMed Central

    Dickin, Sarah K.; Schuster-Wallace, Corinne J.; Elliott, Susan J.

    2013-01-01

    The Water-associated Disease Index (WADI) was developed to identify and visualize vulnerability to different water-associated diseases by integrating a range of social and biophysical determinants in map format. In this study vulnerability is used to encompass conditions of exposure, susceptibility, and differential coping capacity to a water-associated health hazard. By assessing these conditions, the tool is designed to provide stakeholders with an integrated and long-term understanding of subnational vulnerabilities to water-associated disease and contribute to intervention strategies to reduce the burden of illness. The objective of this paper is to describe and validate the WADI tool by applying it to dengue. A systemic ecohealth framework that considers links between people, the environment and health was applied to identify secondary datasets, populating the index with components including climate conditions, land cover, education status and water use practices. Data were aggregated to create composite indicators of exposure and of susceptibility in a Geographic Information System (GIS). These indicators were weighted by their contribution to dengue vulnerability, and the output consisted of an overall index visualized in map format. The WADI was validated in this Malaysia case study, demonstrating a significant association with dengue rates at a sub-national level, and illustrating a range of factors that drive vulnerability to the disease within the country. The index output indicated high vulnerability to dengue in urban areas, especially in the capital Kuala Lumpur and surrounding region. However, in other regions, vulnerability to dengue varied throughout the year due to the influence of seasonal climate conditions, such as monsoon patterns. The WADI tool complements early warning models for water-associated disease by providing upstream information for planning prevention and control approaches, which increasingly require a comprehensive and geographically broad understanding of vulnerability for implementation. PMID:23667642

  12. Dengue Vectors and their Spatial Distribution

    PubMed Central

    Higa, Yukiko

    2011-01-01

    The distribution of dengue vectors, Ae. aegypti and Ae. albopictus, is affected by climatic factors. In addition, since their life cycles are well adapted to the human environment, environmental changes resulting from human activity such as urbanization exert a great impact on vector distribution. The different responses of Ae. aegypti and Ae albopictus to various environments result in a difference in spatial distribution along north-south and urban-rural gradients, and between the indoors and outdoors. In the north-south gradient, climate associated with survival is an important factor in spatial distribution. In the urban-rural gradient, different distribution reflects a difference in adult niches and is modified by geographic and human factors. The direct response of the two species to the environment around houses is related to different spatial distribution indoors and outdoors. Dengue viruses circulate mainly between human and vector mosquitoes, and the vector presence is a limiting factor of transmission. Therefore, spatial distribution of dengue vectors is a significant concern in the epidemiology of the disease. Current technologies such as GIS, satellite imagery and statistical models allow researchers to predict the spatial distribution of vectors in the changing environment. Although it is difficult to confirm the actual effect of environmental and climate changes on vector abundance and vector-borne diseases, environmental changes caused by humans and human behavioral changes due to climate change can be expected to exert an impact on dengue vectors. Longitudinal monitoring of dengue vectors and viruses is therefore necessary. PMID:22500133

  13. Universal Single-Probe RT-PCR Assay for Diagnosis of Dengue Virus Infections

    PubMed Central

    Alm, Erik; Lesko, Birgitta; Lindegren, Gunnel; Ahlm, Clas; Söderholm, Sandra; Falk, Kerstin I.; Lagerqvist, Nina

    2014-01-01

    Background Dengue is a mosquito-borne viral disease that has become more prevalent in the last few decades. Most patients are viremic when they present with symptoms, and early diagnosis of dengue is important in preventing severe clinical complications associated with this disease and also represents a key factor in differential diagnosis. Here, we designed and validated a hydrolysis-probe-based one-step real-time RT-PCR assay that targets the genomes of dengue virus serotypes 1–4. Methodology/Principal Findings The primers and probe used in our RT-PCR assay were designed to target the 3? untranslated region of all complete genome sequences of dengue virus available in GenBank (n?=?3,305). Performance of the assay was evaluated using in vitro transcribed RNA, laboratory-adapted virus strains, external control panels, and clinical specimens. The linear dynamic range was found to be 104–1011 GCE/mL, and the detection limit was between 6.0×102 and 1.1×103 GCE/mL depending on target sequence. The assay did not cross-react with human RNA, nor did it produce false-positive results for other human pathogenic flaviviruses or clinically important etiological agents of febrile illnesses. We used clinical serum samples obtained from returning travelers with dengue-compatible symptomatology (n?=?163) to evaluate the diagnostic relevance of our assay, and laboratory diagnosis performed by the RT-PCR assay had 100% positive agreement with diagnosis performed by NS1 antigen detection. In a retrospective evaluation including 60 archived serum samples collected from confirmed dengue cases 1–9 days after disease onset, the RT-PCR assay detected viral RNA up to 9 days after appearance of symptoms. Conclusions/Significance The validation of the RT-PCR assay presented here indicates that this technique can be a reliable diagnostic tool, and hence we suggest that it be introduced as the method of choice during the first 5 days of dengue symptoms. PMID:25522325

  14. A review of outbreaks of waterborne disease associated with ships: evidence for risk management.

    PubMed Central

    Rooney, Roisin M.; Bartram, Jamie K.; Cramer, Elaine H.; Mantha, Stacey; Nichols, Gordon; Suraj, Rohini; Todd, Ewen C. D.

    2004-01-01

    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

  15. Causes of Outbreaks Associated with Drinking Water in the United States from 1971 to 2006

    PubMed Central

    Craun, Gunther F.; Brunkard, Joan M.; Yoder, Jonathan S.; Roberts, Virginia A.; Carpenter, Joe; Wade, Tim; Calderon, Rebecca L.; Roberts, Jacquelin M.; Beach, Michael J.; Roy, Sharon L.

    2010-01-01

    Summary: Since 1971, the CDC, EPA, and Council of State and Territorial Epidemiologists (CSTE) have maintained the collaborative national Waterborne Disease and Outbreak Surveillance System (WBDOSS) to document waterborne disease outbreaks (WBDOs) reported by local, state, and territorial health departments. WBDOs were recently reclassified to better characterize water system deficiencies and risk factors; data were analyzed for trends in outbreak occurrence, etiologies, and deficiencies during 1971 to 2006. A total of 833 WBDOs, 577,991 cases of illness, and 106 deaths were reported during 1971 to 2006. Trends of public health significance include (i) a decrease in the number of reported outbreaks over time and in the annual proportion of outbreaks reported in public water systems, (ii) an increase in the annual proportion of outbreaks reported in individual water systems and in the proportion of outbreaks associated with premise plumbing deficiencies in public water systems, (iii) no change in the annual proportion of outbreaks associated with distribution system deficiencies or the use of untreated and improperly treated groundwater in public water systems, and (iv) the increasing importance of Legionella since its inclusion in WBDOSS in 2001. Data from WBDOSS have helped inform public health and regulatory responses. Additional resources for waterborne disease surveillance and outbreak detection are essential to improve our ability to monitor, detect, and prevent waterborne disease in the United States. PMID:20610821

  16. Outbreaks of enterotoxigenic Escherichia coli infection in American adults: a clinical and epidemiologic profile.

    PubMed Central

    Dalton, C. B.; Mintz, E. D.; Wells, J. G.; Bopp, C. A.; Tauxe, R. V.

    1999-01-01

    Because enterotoxigenic Escherichia coli (ETEC) is not identified by routine stool culture methods, ETEC outbreaks may go unrecognized, and opportunities for treatment and prevention may be missed. To improve recognition of adult ETEC outbreaks, we compared them with reported outbreaks of viral gastroenteritis. During 1975-95, we identified 14 ETEC outbreaks in the United States and 7 on cruise ships, caused by 17 different serotypes and affecting 5683 persons. Median symptom prevalences were: diarrhoea 99%, abdominal cramps 82%, nausea 49%, fever 22%, vomiting 14%. The median incubation period was 42 h, and for 8 of 10 outbreaks, the mean or median duration of illness was > 72 h (range 24-264). For 17 (81%) ETEC outbreaks, but for only 2 (8%) viral outbreaks, the prevalence of diarrhoea was > or = 2.5 times the prevalence of vomiting. ETEC outbreaks may be differentiated from viral gastroenteritis outbreaks by a diarrhoea-to-vomiting prevalence ratio of > or = 2.5 and a longer duration of illness. PMID:10487636

  17. Determinants of Outbreak Detection Performance

    PubMed Central

    Jafarpour, Nastaran; Precup, Doina; Buckeridge, David

    2013-01-01

    Objective To predict the performance of outbreak detection algorithms under different circumstances which will guide the method selection and algorithm configuration in surveillance systems, to characterize the dependence of the performance of detection algorithms on the type and severity of outbreak, to develop quantitative evidence about determinants of detection performance. Introduction The choice of outbreak detection algorithm and its configuration can result in important variations in the performance of public health surveillance systems. Our work aims to characterize the performance of detectors based on outbreak types. We are using Bayesian networks (BN) to model the relationships between determinants of outbreak detection and the detection performance based on a significant study on simulated data. Methods The simulated surveillance data that we used was generated by Surveillance Lab of McGill University using Simulation Analysis Platform [1] considering surveillance in an urban area to detect waterborne outbreaks due to the failure of a water treatment plant. We focus on predicting the performance of the C-family of algorithms, because they are widely used, state-of-art outbreak detection algorithms [2]. We investigate the influence of algorithm characteristics and outbreak characteristics in determining outbreak detection performance. The C1, C2, and C3 are distinguished by the configuration of 2 parameters,the guardband and memory. Generally, gradually increasing outbreaks can bias the test statistic upward, so the detection algorithm will fail to flag the outbreak. To avoid this situation, the C2 and C3 use a 2-day gap, guardband, between the baseline interval and the test interval. The C3 includes 2 recent observations, called memory, in the computation of the test statistic. The W2 algorithm is a modified version of the C2 which takes weekly patterns of surveillance time series into account [3]. In the W2, the baseline data is stratified to 2 distinct baselines: one for weekdays, the other for weekends. The W3 includes 2 recent observations of each baseline while calculating the test statistic in the corresponding baseline. We ran the C1, C2, C3, W2, and W3 on 18k simulated time series and measured the sensitivity and specificity of detection. Then we created the training data set of 5400000 instances. Each instance was the result of performance evaluation of an outbreak detection algorithm with a specific setting of parameters. In order to investigate the determinants of detection performance and reveal their effects quantitatively, we used BN to predict the performance based on algorithm characteristics and outbreak characteristics. Results We developed 2 BN models in the Weka machine learning software [4] using 5-fold cross-validation. The first BN determines the effect of the guardband, memory, alerting threshold, and the weekly pattern indicator (0 for C-algorithms, 1 for W-algorithms) and outbreak characteristics (contamination level and duration) on the sensitivity of detection. The value of sensitivity was mapped to 4 classes: (0, 0.3], (0.3, 0.6], (0.6, 0.9], (0.9, 1]. The developed BN correctly classified 67.74% of instances. The misclassification error was 0.9407. The second BN for predicting the specificity of detection correctly classified 95.895% of instances in 10 classes and the misclassification error was 0.2975. Conclusions The contamination level and duration of outbreaks, alerting threshold, memory, guardband, and whether the weekly pattern was considered or not influence the sensitivity and specificity of outbreak detection and given the C-algorithm parameter settings, we can predict outbreak detection performance quantitatively. In future work, we plan to investigate other predictors of performance and study how these predictions can be used in algorithm and policy choices.

  18. Clinical and Oral Implications of Dengue Fever: A Review

    PubMed Central

    Roopashri, G; Vaishali, M R; David, Maria Priscilla; Baig, Muqeet; Navneetham, Anuradha; Venkataraghavan, Karthik

    2015-01-01

    Dengue is a viral infection with fatal potential complications. It is also called as break-bone fever. Worldwide dengue infection is the most common mosquito-borne viral disease. It is caused by vector Aedesa egypti and represents a major public health issue in more than 100 tropical countries. The word dengue is obtained from Swahili phrase Ka-dinga pepo meaning “cramplikeseizure.” Dengue viral infections are characterized by abrupt febrile illness, but can also lead to significant morbidity and mortality. Hence, it requires an early and correct diagnosis. Gingival bleeding is the most common oral manifestation of dengue infection. Although oral lesions are uncommon in dengue infections and if manifested, may be mistaken for bleeding disorders. This review emphasizes the significance of oral lesions as it may be the early indicators of dengue hemorrhagic fever.

  19. Dengue: the risk to developed and developing countries.

    PubMed Central

    Monath, T P

    1994-01-01

    Dengue viruses are members of the Flaviviridae, transmitted principally in a cycle involving humans and mosquito vectors. In the last 20 years the incidence of dengue fever epidemics has increased and hyperendemic transmission has been established over a geographically expanding area. A severe form, dengue hemorrhagic fever (DHF), is an immunopathologic disease occurring in persons who experience sequential dengue infections. The risk of sequential infections, and consequently the incidence of DHF, has risen dramatically, first in Asia and now in the Americas. At the root of the emergence of dengue as a major health problem are changes in human demography and behavior, leading to unchecked populations of and increased exposure to the principal domestic mosquito vector, Aedes aegypti. Virus-specified factors also influence the epidemiology of dengue. Speculations on future events in the epidemiology, evolution, and biological expression of dengue are presented. Images PMID:8146129

  20. [Interdisciplinary management of a large Legionella outbreak in Germany].

    PubMed

    Freudenmann, M; Kurz, S; von Baum, H; Reick, D; Schreff, A M; Essig, A; Lück, C; Gonser, T; Brockmann, S O; Härter, G; Eberhardt, B; Embacher, A; Höller, C

    2011-11-01

    Between December 2009 and the end of January 2010, the largest hitherto known outbreak of Legionella in Germany took place in the cities of Ulm and Neu-Ulm. Of a total of 64 patients involved, 60 patients had to be hospitalized, and 5 patients died from the infection. This event was caused by a wet cooling tower of a large air conditioning system in the city center of Ulm. The search for the source of the Legionella emission was extremely difficult, since these plants are neither notifiable nor subject to authorization in Germany. We report about the search for the source and the measures to control the outbreak. We also discuss communication and coordination during these investigations. Regulatory measures as proposed by the World Health Organization (WHO) and the European Network for Legionellosis (EWGLI) and already implemented in numerous other European countries would be desirable to prevent such outbreaks in the future. PMID:22015788

  1. Preliminary evaluation on the efficiency of the kit Platelia Dengue NS1 Ag-ELISA to detect dengue virus in dried Aedes aegypti: a potential tool to improve dengue surveillance

    PubMed Central

    2014-01-01

    Background Surveillance is a critical component of any dengue prevention and control programme. Herein, we investigate the efficiency of the commercial kit Platelia Dengue NS1 Ag-ELISA to detect dengue virus (DENV) antigens in Aedes aegypti mosquitoes infected under laboratory conditions. Methods Under insectary conditions, four to five day-old mosquitoes were orally challenged with DENV-2 titer of 3.6 x 105 PFU equivalent/ml, incubated for 14 days and then killed. At ten time-points following mosquito death (0, 6, 12, 24, 72, 96, 120, 144 and 168 h), i.e., during a one-week period, dried mosquitoes were comparatively tested for the detection of the NS1 antigen with other methods of detection, such as qRT-PCR and virus isolation in C6/36 cells. Results We first observed that the NS1 antigen was more effective in detecting DENV-2 in Ae. aegypti between 12 and 72 h after mosquito death when compared with qRT-PCR. A second round involved comparing the sensitivity of detection of the NS1 antigen and virus isolation in C6/36 cells. The NS1 antigen was also more effective than virus isolation, detecting DENV-2 at all time-points, i.e., up to 168 h after mosquito death. Meanwhile, virus isolation was successful up to 96 h after Ae. aegypti death, but the number of positive samples per time period presented a tendency to decline progressively over time. From the 43 samples positive by the virus isolation technique, 38 (88.4%) were also positive by the NS1 test. Conclusion Taken together, these results are the first to indicate that the NS1 antigen might be an interesting complementary tool to improve dengue surveillance through DENV detection in dried Ae. aegypti females. PMID:24690324

  2. Estimating Costs Associated with a Community Outbreak of Meningococcal Disease in a Colombian Caribbean City

    PubMed Central

    Pinzón-Redondo, Hernando; Coronell-Rodriguez, Wilfrido; Díaz-Martinez, Inés; Guzmán-Corena, Ángel; Constenla, Dagna

    2014-01-01

    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

  3. Sensorineural hearing loss in hemorrhagic dengue?

    PubMed Central

    Ribeiro, Bruna Natália Freire; Guimarães, Alexandre Caixeta; Yazawa, Felipe; Takara, Tammy Fumiko Messias; de Carvalho, Guilherme Machado; Zappelini, Carlos Eduardo Monteiro

    2014-01-01

    Introduction Dengue is an acute febrile infectious disease, with high fever followed by symptoms flu-like. Dengue hemorrhagic fever (DHF) is a vascular leak syndrome and could present spontaneous bleeding and worsening of symptoms after some days. Dengue could have some ENT manifestations, however hearing loss is not one of them. Sudden hearing loss is considered as sensorineural or perceptual hearing loss with a sudden onset in a person without other prior otological history. The relation between infectious diseases and sudden hearing are been investigated, some viruses were already linked, but the relation between dengue virus and sudden hearing still remains unknown. This article has the goal of presenting a case of DHF that evolved with SSHL in his hospitalization process. Presentation of case We report a 60 years-male patient of with DHF who developed bilateral secretory otitis media and sensorineural hearing loss after the fifth day of onset of symptoms. His hearing loss remained even after 7 months and the patient was referred for hearing aid fitting. Discussion and conclusion This is the first case report that brings together DHF and sudden hearing loss. In the development of this case no other cause to sudden hearing loss was found and the correlation between dengue and hearing loss was questioned. In the literature review was found that some viruses, as mumps virus, varicella-zoster virus and HSV-1 and HSV-2 are related to sudden hearing loss, all of them fit in the viral theory. Besides the viral theory of sudden hearing loss, there is the vascular theory that is the occlusion of the end artery that supplies the cochlea. DHF has a vascular commitment, and the hypothesis of a vascular cause could be elicited in this case. Many studies in this area are needed and this article has the objective of elicit the discussion about the subject. Could dengue be associated with sensorineural hearing loss? PMID:25625489

  4. Evaluation of the Diagnostic Accuracy of a New Dengue IgA Capture Assay (Platelia Dengue IgA Capture, Bio-Rad) for Dengue Infection Detection

    PubMed Central

    De Decker, Sophie; Vray, Muriel; Sistek, Viridiana; Labeau, Bhety; Enfissi, Antoine; Rousset, Dominique; Matheus, Séverine

    2015-01-01

    Considering the short lifetime of IgA antibodies in serum and the key advantages of antibody detection ELISAs in terms of sensitivity and specificity, Bio-Rad has just developed a new ELISA test based on the detection of specific anti-dengue IgA. This study has been carried out to assess the performance of this Platelia Dengue IgA Capture assay for dengue infection detection. A total of 184 well-characterized samples provided by the French Guiana NRC sera collection (Laboratory of Virology, Institut Pasteur in French Guiana) were selected among samples collected between 2002 and 2013 from patients exhibiting a dengue-like syndrome. A first group included 134 sera from confirmed dengue-infected patients, and a second included 50 sera from non-dengue infected patients, all collected between day 3 and day 15 after the onset of fever. Dengue infection diagnoses were all confirmed using reference assays by direct virological identification using RT-PCR or virus culture on acute sera samples or on paired acute-phase sera samples of selected convalescent sera. This study revealed: i) a good overall sensitivity and specificity of the IgA index test, i.e., 93% and 88% respectively, indicating its good correlation to acute dengue diagnosis; and ii) a good concordance with the Panbio IgM capture ELISA. Because of the shorter persistence of dengue virus-specific IgA than IgM, these results underlined the relevance of this new test, which could significantly improve dengue diagnosis accuracy, especially in countries where dengue virus is (hyper-) endemic. It would allow for additional refinement of dengue diagnostic strategy. PMID:25803718

  5. 78 FR 16505 - Prospective Grant of Exclusive License: Chimeric West Nile/Dengue Viruses

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-15

    ...License: Chimeric West Nile/Dengue Viruses AGENCY: Centers for Disease Control and...use of in vitro diagnostics for dengue virus infection, to practice the inventions...Engineered, Chimeric West Nile/Dengue Viruses;'' PCT Application...

  6. Large outbreak of Legionnaires' disease and Pontiac fever at a military base.

    PubMed

    Ambrose, J; Hampton, L M; Fleming-Dutra, K E; Marten, C; McClusky, C; Perry, C; Clemmons, N A; McCormic, Z; Peik, S; Mancuso, J; Brown, E; Kozak, N; Travis, T; Lucas, C; Fields, B; Hicks, L; Cersovsky, S B

    2014-11-01

    We investigated a mixed outbreak of Legionnaires' disease (LD) and Pontiac fever (PF) at a military base to identify the outbreak's environmental source as well as known legionellosis risk factors. Base workers with possible legionellosis were interviewed and, if consenting, underwent testing for legionellosis. A retrospective cohort study collected information on occupants of the buildings closest to the outbreak source. We identified 29 confirmed and probable LD and 38 PF cases. All cases were exposed to airborne pathogens from a cooling tower. Occupants of the building closest to the cooling tower were 6·9 [95% confidence interval (CI) 2·2-22·0] and 5·5 (95% CI 2·1-14·5) times more likely to develop LD and PF, respectively, than occupants of the next closest building. Thorough preventive measures and aggressive responses to outbreaks, including searching for PF cases in mixed legionellosis outbreaks, are essential for legionellosis control. PMID:25267405

  7. A Call to Action to Enhance Filovirus Disease Outbreak Preparedness and Response

    PubMed Central

    Roddy, Paul

    2014-01-01

    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. PMID:25271875

  8. Immunogenicity and safety of recombinant tetravalent dengue vaccine (CYD-TDV) in individuals aged 2–45 years

    PubMed Central

    Sin Leo, Yee; Wilder-Smith, Annelies; Archuleta, Sophia; Shek, Lynette P.; Chong, Chia Yin; Nam Leong, Hoe; Yong Low, Chian; Oh, May-Lin Helen; Bouckenooghe, Alain; Wartel, T. Anh; Crevat, Denis

    2012-01-01

    This was a multicenter, blinded, Phase II study (NCT00880893) conducted in Singapore. The primary objectives were to evaluate the safety of a tetravalent dengue vaccine (TDV) comprising four recombinant, live, attenuated viruses (CYD-TDV) and the dengue virus serotype-specific antibody responses before and 28 d after each vaccination. Participants were randomized 3:1 to receive three doses of CYD-TDV or a control vaccine at 0, 6 and 12 mo. Control vaccine was placebo for the first dose (all ages) and for subsequent doses, licensed hepatitis-A for children (aged 2–11 years) or influenza vaccine for adolescents (12–17 years) and adults (18–45 years). Between April and October 2009, 317 children, 187 adolescents and 696 adults were enrolled. In all age groups, reactogenicity was higher after the first injection of CYD-TDV than after placebo control. Reactogenicity after subsequent CYD-TDV doses was no higher than after the first dose, and tended to be lower or similar to that seen after active control vaccination. Seropositivity rates and geometric mean neutralizing antibody titers (GMTs; 1/dil) against all four dengue virus serotypes increased in all age groups after each of the three CYD-TDV doses. Post-dose 3, 66.5% of all participants were seropositive to all four serotypes, and 87.2% were seropositive to ? 3 serotypes; GMTs for all participants ranged from 43.0 against dengue virus serotype 1 to 100 against dengue virus serotype 4. GMTs were higher in children than in adolescents. These results support the continued development of CYD-TDV for the prevention of dengue disease. PMID:22894958

  9. Beriberi outbreak among commercial fishermen, Thailand 2005.

    PubMed

    Doung-ngern, P; Kesornsukhon, S; Kanlayanaphotporn, J; Wanadurongwan, S; Songchitsomboon, S

    2007-01-01

    In April 2005, The Tahi Bureau of Epidemiology investigated a reported outbreak of beriberi among commercial fishermen in Maha Chai, a port city in the Gulf of Thailand. The objective of this study was to verify the diagnosis of beriberi in affected individuals, describe the possible outbreak, ascertain risk factors, and provide prevention and control measures. We interviewed ill persons and treating doctors, and reviewed medical records to conduct a descriptive study. A probable case was defined as a crewmember of Ship A with one of the following: leg edema scrotal edema or ascites, dyspnea, chest discomfort, chest pain, extremity numbness, or extremity weakness. Confirmed cases were those with clinical criteria and laboratory findings consistent with thiamine deficiency. The outbreak started in early March, 2005 and continued until March 31, 2005. Ship A had 28 crewmembers (four Thai, 24 Myanmar). Overall, there were 15 probable cases (attack rate 53.6%, with three confirmed and 12 probable cases). Only three were tested for Vitamin B1 deficiency. All cases were male, with a median age of 28 years (range 20-45). Fourteen of the 15 cases were Myanmar and one Thai. Due to limited resources, the crew ate only seafood and polished rice for almost two months prior to symptoms. Symptoms included edema (60%), chest discomfort (54%), and dyspnea (27%). Two persons died while on board the ship (case fatality 13%). The total time at sea for Ship A was 18 months, including a five-month delay in docking due to licensing problems. PMID:17539258

  10. Internal travel and risk of dengue transmission in Colombia.

    PubMed

    Chaparro, Pablo E; de la Hoz, Fernando; Lozano Becerra, Juan C; Repetto, Silvia A; Alba Soto, Catalina D

    2014-09-01

    Human behavior plays a key role in the dynamics of dengue transmission. However, research on the relationship between human movement and dengue transmission within endemic countries is limited. From January 2008 to December 2011, the authors of this study conducted a retrospective analysis of imported dengue infections in Bogotá, Colombia. Bogotá is a vector-transmission-free city that is also the capital district and most populated municipality in Colombia. The study revealed that 1) Bogotá inhabitants acquired dengue infection in diverse localities throughout the country but the largest proportion of cases (35.6%) were contracted at popular tourist destinations in dengue-endemic areas near Bogotá (<200-km radius from city limits), and 2) the number of imported dengue cases increased after major holidays, a transmission pattern not seen in dengue-endemic areas, where disease incidence correlates with rainy periods. It is therefore recommended that physicians consider the effect of travel when diagnosing their patients' illnesses, especially outside dengue-endemic areas where diagnosis of the disease can be challenging due to its nonspecific symptoms. The study also showed that analysis of dengue cases imported to regions free of vector transmission can generate an evidence-based model for characterizing the impact of human movement on the spread of diseases like dengue in countries where they are endemic. PMID:25418771

  11. Climate-driven mathematical models to understand the spatio-temporal heterogeneity of a chikungunya outbreak in the presence of widespread asymptomatic infection

    NASA Astrophysics Data System (ADS)

    Dommar, Carlos J.; Robinson, Marguerite; Lowe, Rachel; Conan, Anne; Buchy, Philippe; Tarantola, Arnaud; Rodó, Xavier

    2014-05-01

    The emergence and persistence of human pathogens in the environment represents a constant threat to society, with global implications for human health, economies and ecosystems. Of particular concern are vector-borne diseases, such as dengue, malaria and chikungunya, which are increasing across their traditional ranges and continuing to infiltrate new regions. This unprecedented situation has been partly attributed to the increase in global temperatures in recent decades which has allowed non-native mosquito species to invade and successfully colonise previously inhospitable environments. The spatio-temporal evolution of these diseases is determined by the interaction of the host and vector, which is strongly dependent on social structures and mobility patterns. In turn, vector populations are thought to be driven by external environmental variables, such as precipitation and temperature. Furthermore, the ability of asymptomatic individuals to successfully transmit the infection and evade control measures can undermine public health interventions. We employed a stochastic model, which explicitly included asymptomatic and undocumented laboratory confirmed cases, and applied it to a documented outbreak in Cambodia in 2012 (Trapeang Roka village, Kampong Speu Province). The resulting estimate of the reproduction number was considerably higher than values obtained for previous outbreaks and highlights the importance of asymptomatic transmission. Subsequently, we develop an agent-based model (ABM), in which each individual is explicitly represented and vector populations are linked to precipitation estimates in a tropical setting. The model is implemented on both scale-free and regular networks. The spatio-temporal transmission of chikungunya is analysed and the presence of asymptomatic silent spreaders within the population is investigated in the context of implementing travel restrictions during an outbreak. Preventing the movement of symptomatic individuals alone is found to be an insufficient mechanism to halt the spread of the disease, which can be readily carried to neighbouring nodes via sub-clinical individuals. Furthermore, the impact of topology structure versus precipitation levels is assessed and precipitation is found to be the dominant factor driving spatio-temporal transmission. Our results highlight the urgent need to establish adequate monitoring and mosquito control programs in vulnerable countries. These models can help to inform public health officials on both the impact and potential spatial expansion of vector-borne diseases through both urban and rural regions under the influence of dynamic climatic conditions. Given the climate sensitivity of vector-borne diseases, such as chikungunya, it is important to link the monitoring of meteorological conditions to public health surveillance and control.

  12. Using climate information to understand the spatio-temporal heterogeneity of a chikungunya outbreak in the presence of widespread asymptomatic infection

    NASA Astrophysics Data System (ADS)

    Dommar, C. J.; Lowe, R.; Robinson, M.; Rodó, X.

    2013-12-01

    The emergence and persistence of human pathogens in the environment represents a constant threat to society, with global implications for human health, economies and ecosystems. Of particular concern are vector-borne diseases, such as dengue, malaria and chikungunya, which are increasing across their traditional ranges and continuing to infiltrate new regions. This unprecedented situation has been partly attributed to the increase in global temperatures in recent decades which has allowed non-native mosquito species to invade and successfully colonise previously inhospitable environments The spatio-temporal evolution of these diseases is determined by the interaction of the host and vector, which is strongly dependent on social structures and mobility patterns. In turn, vector populations are thought to be driven by external environmental variables, such as precipitation and temperature. Furthermore, the ability of asymptomatic individuals to successfully transmit the infection and evade control measures can undermine public health interventions. We employed a stochastic model, which explicitly included asymptomatic and undocumented laboratory confirmed cases, and applied it to a documented outbreak in Cambodia in 2012 (Trapeang Roka village, Kampong Speu Province). The resulting estimate of the reproduction number was considerably higher than values obtained for previous outbreaks and highlights the importance of asymptomatic transmission. Subsequently, we develop an agent-based model (ABM), in which each individual is explicitly represented and vector populations are linked to precipitation estimates in a tropical setting. The model is implemented on both scale-free and regular networks. The spatio-temporal transmission of chikungunya is analysed and the presence of asymptomatic silent spreaders within the population is investigated in the context of implementing travel restrictions during an outbreak. Preventing the movement of symptomatic individuals alone is found to be an insufficient mechanism to halt the spread of the disease, which can be readily carried to neighbouring nodes via sub-clinical individuals. Furthermore, the impact of topology structure versus precipitation levels is assessed and precipitation is found to be the dominant factor driving spatio-temporal transmission. Our results highlight the urgent need to establish adequate monitoring and mosquito control programs in vulnerable countries. These models can help to inform public health officials on both the impact and potential spatial expansion of vector-borne diseases through both urban and rural regions under the influence of dynamic climatic conditions. Given the climate sensitivity of vector-borne diseases, such as chikungunya, it is important to link the monitoring of meteorological conditions to public health surveillance and control.

  13. Complete genome sequencing and evolutionary phylogeography analysis of Indian isolates of Dengue virus type 1.

    PubMed

    Dash, Paban Kumar; Sharma, Shashi; Soni, Manisha; Agarwal, Ankita; Sahni, Ajay Kumar; Parida, Manmohan

    2015-01-01

    Dengue is now hyper-endemic in most parts of south and southeast Asia including India. The northern India particularly national capital New Delhi witnessed major Dengue outbreaks with Dengue virus type 1 (DENV-1) as the dominant serotype since last five years. This study was initiated to decipher the complete genome information of recently circulating DENV-1 (2009-2011) along with the prototype Indian DENV-1, isolated in 1956. Further extensive ML phylogenetic and Bayesian phylogeography analysis was carried out to investigate the evolution of this virus and understand its spatiotemporal diffusion across the globe. The complete genome analysis revealed deletion of a unique 21-nucleotide stretch in the 3' un-translated region of recent Indian DENV-1. The north Indian DENV-1 revealed up to 5.2% nucleotide sequence difference compared to recent isolates from southern India. Selection pressure analysis revealed positive selection in few amino acid sites of both structural and non-structural proteins. The molecular phylogeny classified the Indian DENV-1 into genotype III, which is also known as cosmopolitan genotype. The northern and southern Indian DENV-1 were grouped into distinct clades. The molecular clock analysis estimated a mean evolutionary rate of 7.08×10(-4) substitutions/site/year for cosmopolitan genotype. The phylogeography analysis revealed that the cosmopolitan genotype DENV-1 originated ?1938 in India and subsequently spread globally. The diffusion of virus from India to Caribbean and South America was confirmed through SPREAD analysis. This study also confirmed the temporal displacement of different clades of DENV-1 in India over last five decades. PMID:25197040

  14. El Niño Southern Oscillation and vegetation dynamics as predictors of dengue fever cases in Costa Rica

    NASA Astrophysics Data System (ADS)

    Fuller, D. O.; Troyo, A.; Beier, J. C.

    2009-01-01

    Dengue fever (DF) and dengue hemorrhagic fever (DHF) are growing health concerns throughout Latin America and the Caribbean. This study focuses on Costa Rica, which experienced over 100 000 cases of DF/DHF from 2003 to 2007. We utilized data on sea-surface temperature anomalies related to the El Niño Southern Oscillation (ENSO) and two vegetation indices derived from the Moderate Resolution Imaging Spectrometer (MODIS) from the Terra satellite to model the influence of climate and vegetation dynamics on DF/DHF cases in Costa Rica. Cross-correlations were calculated to evaluate both positive and negative lag effects on the relationships between independent variables and DF/DHF cases. The model, which utilizes a sinusoid and non-linear least squares to fit case data, was able to explain 83% of the variance in weekly DF/DHF cases when independent variables were shifted backwards in time. When the independent variables were shifted forward in time, consistently with a forecasting approach, the model explained 64% of the variance. Importantly, when five ENSO and two vegetation indices were included, the model reproduced a major DF/DHF epidemic of 2005. The unexplained variance in the model may be due to herd immunity and vector control measures, although information regarding these aspects of the disease system are generally lacking. Our analysis suggests that the model may be used to predict DF/DHF outbreaks as early as 40 weeks in advance and may also provide valuable information on the magnitude of future epidemics. In its current form it may be used to inform national vector control programs and policies regarding control measures; it is the first climate-based dengue model developed for this country and is potentially scalable to the broader region of Latin America and the Caribbean where dramatic increases in DF/DHF incidence and spread have been observed.

  15. Identification of Carboxylesterase Genes Implicated in Temephos Resistance in the Dengue Vector Aedes aegypti

    PubMed Central

    Poupardin, Rodolphe; Srisukontarat, Wannaporn; Yunta, Cristina; Ranson, Hilary

    2014-01-01

    Background Thailand is currently experiencing one of its worst dengue outbreaks in decades. As in most countries where this disease is endemic, dengue control in Thailand is largely reliant on the use of insecticides targeting both immature and adult stages of the Aedes mosquito, with the organophosphate insecticide, temephos, being the insecticide of choice for attacking the mosquito larvae. Resistance to temephos was first detected in Aedes aegypti larvae in Thailand approximately 25 years ago but the mechanism responsible for this resistance has not been determined. Principal Findings Bioassays on Ae. aegypti larvae from Thailand detected temephos resistance ratios ranging from 3.5 fold in Chiang Mai to nearly 10 fold in Nakhon Sawan (NS) province. Synergist and biochemical assays suggested a role for increased carboxylesterase (CCE) activities in conferring temephos resistance in the NS population and microarray analysis revealed that the CCE gene, CCEae3a, was upregulated more than 60 fold in the NS population compared to the susceptible population. Upregulation of CCEae3a was shown to be partially due to gene duplication. Another CCE gene, CCEae6a, was also highly regulated in both comparisons. Sequencing and in silico structure prediction of CCEae3a showed that several amino acid polymorphisms in the NS population may also play a role in the increased resistance phenotype. Significance Carboxylesterases have previously been implicated in conferring temephos resistance in Ae aegypti but the specific member(s) of this family responsible for this phenotype have not been identified. The identification of a strong candidate is an important step in the development of new molecular diagnostic tools for management of temephos resistant populations and thus improved control of dengue. PMID:24651719

  16. Molecular Epidemiology of Dengue Viruses Co-circulating in Upper Myanmar in 2006

    PubMed Central

    Thant, Kyaw Zin; Tun, Mya Myat Ngwe; Parquet, Maria del Carmen; Inoue, Shingo; Lwin, Yee Yee; Lin, Sanda; Aye, Kay Thi; Khin, Pe Thet; Myint, Tin; Htwe, Khin; Nabeshima, Takeshi; Morita, Kouichi

    2015-01-01

    To understand the molecular epidemiology of circulating dengue viruses (DENV) in Upper Myanmar, DENV isolation was attempted by inoculating the sera of a panel of 110 serum samples onto a C6/36 mosquito cell line. The samples were collected from dengue (DEN) patients admitted at Mandalay Children’s Hospital in 2006. Infected culture fluids were subjected to a RT-PCR to detect the DENV genome. Three DENV strains were isolated. This was the first DENV isolation performed either in Mandalay or in Upper Myanmar. One strain belonged to DENV serotype-3 (DENV-3), and two other strains belonged to DENV serotype-4 (DEN-4). The sequence data for the envelope gene of these strains were used in a phylogenetic comparison of DENV-3 and DENV-4 from various countries. Phylogenetic analyses revealed that this DENV-3 strain was clustered within genotype II, and the two DENV-4 strains were clustered within genotype I in each serotype. The Myanmar strains were closely related to strains from the neighboring countries of Thailand and Bangladesh. These results are important for elucidating the trends of recent and future DEN outbreaks in Myanmar.

  17. CD8+ T lymphocyte expansion, proliferation and activation in dengue fever.

    PubMed

    de Matos, Andréia Manso; Carvalho, Karina Inacio; Rosa, Daniela Santoro; Villas-Boas, Lucy Santos; da Silva, Wanessa Cardoso; Rodrigues, Célia Luiza de Lima; Oliveira, Olímpia Massae Nakasone Peel Furtado; Levi, José Eduardo; Araújo, Evaldo Stanislau Affonso; Pannuti, Claudio Sergio; Luna, Expedito José Albuquerque; Kallas, Esper George

    2015-02-01

    Dengue fever induces a robust immune response, including massive T cell activation. The level of T cell activation may, however, be associated with more severe disease. In this study, we explored the level of CD8+ T lymphocyte activation in the first six days after onset of symptoms during a DENV2 outbreak in early 2010 on the coast of São Paulo State, Brazil. Using flow cytometry we detected a progressive increase in the percentage of CD8+ T cells in 74 dengue fever cases. Peripheral blood mononuclear cells from 30 cases were thawed and evaluated using expanded phenotyping. The expansion of the CD8+ T cells was coupled with increased Ki67 expression. Cell activation was observed later in the course of disease, as determined by the expression of the activation markers CD38 and HLA-DR. This increased CD8+ T lymphocyte activation was observed in all memory subsets, but was more pronounced in the effector memory subset, as defined by higher CD38 expression. Our results show that most CD8+ T cell subsets are expanded during DENV2 infection and that the effector memory subset is the predominantly affected sub population. PMID:25675375

  18. Recurring outbreaks of Salmonella typhimurium phage type 135 associated with the consumption of products containing raw egg in Tasmania.

    PubMed

    Stephens, Nicola; Coleman, David; Shaw, Kathleen

    2008-12-01

    Large egg-associated outbreaks of Salmonella Typhimurium 135 (STm135) that were associated with inadequate food safety practices but also linked to a common poultry farm occurred in Tasmania in 2005. A series of public health interventions were implemented to prevent further occurrences but 2 more egg-associated outbreaks in Tasmania in March 2007 and January 2008 led to a further 66 cases of STm135. This report describes these outbreaks and their links to the common source associated with the outbreaks in 2005. PMID:19374277

  19. Dengue: recent past and future threats

    PubMed Central

    Rogers, David J.

    2015-01-01

    This article explores four key questions about statistical models developed to describe the recent past and future of vector-borne diseases, with special emphasis on dengue: (1)?How many variables should be used to make predictions about the future of vector-borne diseases?(2)?Is the spatial resolution of a climate dataset an important determinant of model accuracy?(3)?Does inclusion of the future distributions of vectors affect predictions of the futures of the diseases they transmit?(4)?Which are the key predictor variables involved in determining the distributions of vector-borne diseases in the present and future?Examples are given of dengue models using one, five or 10 meteorological variables and at spatial resolutions of from one-sixth to two degrees. Model accuracy is improved with a greater number of descriptor variables, but is surprisingly unaffected by the spatial resolution of the data. Dengue models with a reduced set of climate variables derived from the HadCM3 global circulation model predictions for the 1980s are improved when risk maps for dengue's two main vectors (Aedes aegypti and Aedes albopictus) are also included as predictor variables; disease and vector models are projected into the future using the global circulation model predictions for the 2020s, 2040s and 2080s. The Garthwaite–Koch corr-max transformation is presented as a novel way of showing the relative contribution of each of the input predictor variables to the map predictions. PMID:25688021

  20. Dengue: recent past and future threats.

    PubMed

    Rogers, David J

    2015-04-01

    This article explores four key questions about statistical models developed to describe the recent past and future of vector-borne diseases, with special emphasis on dengue: (1)?How many variables should be used to make predictions about the future of vector-borne diseases? (2)?Is the spatial resolution of a climate dataset an important determinant of model accuracy? (3)?Does inclusion of the future distributions of vectors affect predictions of the futures of the diseases they transmit? (4)?Which are the key predictor variables involved in determining the distributions of vector-borne diseases in the present and future? Examples are given of dengue models using one, five or 10 meteorological variables and at spatial resolutions of from one-sixth to two degrees. Model accuracy is improved with a greater number of descriptor variables, but is surprisingly unaffected by the spatial resolution of the data. Dengue models with a reduced set of climate variables derived from the HadCM3 global circulation model predictions for the 1980s are improved when risk maps for dengue's two main vectors (Aedes aegypti and Aedes albopictus) are also included as predictor variables; disease and vector models are projected into the future using the global circulation model predictions for the 2020s, 2040s and 2080s. The Garthwaite-Koch corr-max transformation is presented as a novel way of showing the relative contribution of each of the input predictor variables to the map predictions. PMID:25688021

  1. Multiobjective Genetic Algorithm applied to dengue control.

    PubMed

    Florentino, Helenice O; Cantane, Daniela R; Santos, Fernando L P; Bannwart, Bettina F

    2014-12-01

    Dengue fever is an infectious disease caused by a virus of the Flaviridae family and transmitted to the person by a mosquito of the genus Aedes aegypti. This disease has been a global public health problem because a single mosquito can infect up to 300 people and between 50 and 100 million people are infected annually on all continents. Thus, dengue fever is currently a subject of research, whether in the search for vaccines and treatments for the disease or efficient and economical forms of mosquito control. The current study aims to study techniques of multiobjective optimization to assist in solving problems involving the control of the mosquito that transmits dengue fever. The population dynamics of the mosquito is studied in order to understand the epidemic phenomenon and suggest strategies of multiobjective programming for mosquito control. A Multiobjective Genetic Algorithm (MGA_DENGUE) is proposed to solve the optimization model treated here and we discuss the computational results obtained from the application of this technique. PMID:25230238

  2. Internet and Free Press Are Associated with Reduced Lags in Global Outbreak Reporting

    PubMed Central

    McAlarnen, Lindsey; Smith, Katherine; Brownstein, John S.; Jerde, Christopher

    2014-01-01

    Background: Global outbreak detection and reporting have generally improved for a variety of infectious diseases and geographic regions in recent decades. Nevertheless, lags in outbreak reporting remain a threat to the global human health and economy. In the time between first occurrence of a novel disease incident and public notification of an outbreak, infected individuals have a greater possibility of traveling and spreading the pathogen to other nations. Shortening outbreak reporting lags has the potential to improve global health by preventing local outbreaks from escalating into global epidemics. Methods: Reporting lags between the first record and the first public report of an event were calculated for 318 outbreaks occurring 1996-2009. The influence of freedom of the press, Internet usage, per capita health expenditure, and cell phone subscriptions, on the timeliness of outbreak reporting was evaluated. Results: Freer presses and increasing Internet usage correlate with reduced time between the first record of an outbreak and the public report. Increasing Internet usage reduced the expected reporting lag from more than one month in nations without Internet users to one day in those where 75 of 100 people use the Internet. Conclusion: Advances in technology and the emergence of more open and free governments are associated with to improved global infectious disease surveillance. PMID:25642380

  3. Quantity of dengue virus required to infect rhesus monkeys.

    PubMed

    Kraiselburd, E; Gubler, D J; Kessler, M J

    1985-01-01

    As part of a dengue vaccine study, it was necessary to determine how much virus was required to infect rhesus monkeys. Serial dilutions of dengue 2 and 4 viruses were inoculated subcutaneously into groups of five monkeys and seroconversions determined on days 30 and 60 post-inoculation. The viruses were also titrated simultaneously in LLC-MK2 cells and mosquitoes. It was calculated that 9.5 mosquito infectious doses 50 (MID50) of dengue 2 virus and 22 MID50 of dengue 4 virus were required to infect 50% of the monkeys. The data suggest that 100 MID50 of dengue virus should be used as a challenge dose for monkeys previously immunized with dengue vaccine. PMID:2860743

  4. [Update on outbreaks reported from neonatal intensive care units (2010-203): Staphylococcus aureus].

    PubMed

    Kraus-Haas, Martina; Mielke, Martin; Simon, Arne

    2015-03-01

    In terms of the unique risk profile of the patients and the morbidity associated with S. aureus infections in this vulnerable patient population, the literature on outbreaks of S. aureus (including MRSA) in neonatal intensive care units (NICUs) needs to be analyzed separately from reports derived from other intensive care units. With the objective of updating important information for those involved in outbreak management and fostering preventive efforts, this article summarizes the results of a systematic literature analysis, referring to an earlier publication by Gastmeier et al. It focuses on NICU outbreaks caused by S. aureus (including MRSA) and on controlling them. PMID:25566845

  5. Outbreaks of infectious disease associated with private drinking water supplies in England and Wales 1970-2000.

    PubMed Central

    Said, B.; Wright, F.; Nichols, G. L.; Reacher, M.; Rutter, M.

    2003-01-01

    In England and Wales over the last 30 years there have been 25 reported outbreaks of infection, associated with private water supplies (PWS). The majority (16 outbreaks) were reported after the introduction of enhanced surveillance. Although PWS only serve 0.5% of the population, 36% of drinking water outbreaks are associated with PWS. The main pathogen, campylobacter, was implicated in 13 (52%) outbreaks. Most reported outbreaks (88%) occurred in commercial or Category Two supplies, which potentially affect larger populations. The main factors implicated in these outbreaks are temporary or transient populations, treatment (lack or failure), the presence of animals and heavy rains. The public health problem associated with PWS could be prevented by the identification and understanding of risk factors, by the proper protection of water sources and adequate treatment and maintenance. This could be facilitated through the introduction of a risk assessment as part of a scheme for PWS. PMID:12825731

  6. Malaria outbreaks in China (1990–2013): a systematic review

    PubMed Central

    2014-01-01

    Background China has already achieved remarkable accomplishments in shrinking the malaria burden since the mid-20th Century. The country now plans to eliminate malaria by the year 2020. Looking at the dynamics of malaria outbreaks during the last decades might provide important information regarding the potential challenges of such an elimination strategy and might help to avoid mistakes of the past. Methods A systematic review of the published literature (English and Chinese) was conducted to identify malaria outbreaks during the period 1990 until 2013 in China. The main causes of outbreaks as described in these papers were categorized according to whether they were related to population migration, environmental factors, vector and host related factors, and operational problems of the health services. Results The review identified 36 malaria outbreaks over the 23-year study period, on which sufficient information was available. They mainly occurred in southern and central China involving 12 provinces/autonomous regions. More than half of all outbreaks (21/36, 58%) were attributed at least in part to population migration, with malaria importation to non- or low-endemic areas from high-endemic Chinese areas (13/15) or endemic countries (2/15) having been the most frequent reason (15/21, 71%). Other main causes were problems of the health services (15/36, 42%), in particular poor malaria case management (10/15, 67%), environmental factors (7/36, 19%), and vector and host related factors (5/36, 14%). Conclusions Beside a number of other challenges, addressing population movement causing malaria appears to be of particular importance to the national malaria programme. Strengthening of surveillance for malaria and early radical treatment of cases should thus be considered among the most important tools for preventing malaria outbreaks and for the final goal of malaria elimination in China. PMID:25012078

  7. Rubella outbreak in the union territory of Chandigarh, North India.

    PubMed

    Singh, Mini P; Kumar, Archit; Gautam, Neha; Khurana, Jasmine; Gupta, Madhu; Ratho, Radha Kanta

    2015-02-01

    Rubella virus outbreaks usually occur when a large numbers of susceptible individuals accumulate. The disease presents clinically with fever and maculopapular rash. The present study reports the investigation of rubella outbreak in a modern and well-planned village near Chandigarh, North India. The blood samples were collected from 39 cases with febrile rash and from 15 age and sex matched healthy controls residing in the same locality and subjected for the detection of Rubella IgM and IgG antibodies by Enzyme linked immunosorbent assay. The throat swabs, urine and blood samples from acute cases were also collected and subjected to RT-PCR using the primers targeting the E1 region. The genetic characterization of the rubella virus was carried out to identify the circulating genotypes. In the present outbreak, 13 laboratory confirmed cases were reported. Rubella IgM antibodies were detected in 12/39 (30.7%) patients. Rubella RNA could be detected in 83.3% (5/6) of urine, 22.2% (2/9) of throat swabs, and 8.3% (1/12) of blood samples. The rubella genotype responsible for the present outbreak was identified as genotype 1a. This outbreak highlights the need for the introduction of rubella vaccine in the National Immunization Programme of India to prevent outbreaks and to aim towards the eradication of this disease. This study reports the presence of genotype 1a in North India for the first time and stresses the need for further molecular work to identify the circulating strains of the virus. PMID:25156964

  8. The Effects of Weather and Climate Change on Dengue

    PubMed Central

    Colón-González, Felipe J.; Fezzi, Carlo; Lake, Iain R.; Hunter, Paul R.

    2013-01-01

    Background There is much uncertainty about the future impact of climate change on vector-borne diseases. Such uncertainty reflects the difficulties in modelling the complex interactions between disease, climatic and socioeconomic determinants. We used a comprehensive panel dataset from Mexico covering 23 years of province-specific dengue reports across nine climatic regions to estimate the impact of weather on dengue, accounting for the effects of non-climatic factors. Methods and Findings Using a Generalized Additive Model, we estimated statistically significant effects of weather and access to piped water on dengue. The effects of weather were highly nonlinear. Minimum temperature (Tmin) had almost no effect on dengue incidence below 5°C, but Tmin values above 18°C showed a rapidly increasing effect. Maximum temperature above 20°C also showed an increasing effect on dengue incidence with a peak around 32°C, after which the effect declined. There is also an increasing effect of precipitation as it rose to about 550 mm, beyond which such effect declines. Rising access to piped water was related to increasing dengue incidence. We used our model estimations to project the potential impact of climate change on dengue incidence under three emission scenarios by 2030, 2050, and 2080. An increase of up to 40% in dengue incidence by 2080 was estimated under climate change while holding the other driving factors constant. Conclusions Our results indicate that weather significantly influences dengue incidence in Mexico and that such relationships are highly nonlinear. These findings highlight the importance of using flexible model specifications when analysing weather–health interactions. Climate change may contribute to an increase in dengue incidence. Rising access to piped water may aggravate dengue incidence if it leads to increased domestic water storage. Climate change may therefore influence the success or failure of future efforts against dengue. PMID:24244765

  9. Estimating the risk of fire outbreaks in the natural environment

    Microsoft Academic Search

    Daniela Stojanova; Andrej Kobler; Peter Ogrinc; Bernard Ženko; Sašo Džeroski

    A constant and controlled level of emission of carbon and other gases into the atmosphere is a pre-condition for preventing\\u000a global warming and an essential issue for a sustainable world. Fires in the natural environment are phenomena that extensively\\u000a increase the level of greenhouse emissions and disturb the normal functioning of natural ecosystems. Therefore, estimating\\u000a the risk of fire outbreaks

  10. Seir Model for Transmission of Dengue Fever in Selangor Malaysia

    NASA Astrophysics Data System (ADS)

    Syafruddin, S.; Noorani, M. S. M.

    In this paper, we study a system of differential equations that models the population dynamics of SEIR vector transmission of dengue fever. The model studied breeding value based on the number of reported cases of dengue fever in Selangor because the state had the highest case in Malaysia. The model explains that maximum level of human infection rate of dengue fever achieved in a very short period. It is also revealed that there existed suitability result between theoretical and empirical calculation using the model. The result of SEIR model will hopefully provide an insight into the spread of dengue fever in Selangor Malaysia and basic form for modeling this area.

  11. The use of Toxorhynchites splendens for identification and quantitation of serotypes contained in the tetravalent live attenuated dengue vaccine

    Microsoft Academic Search

    Nuananong Jirakanjanakit; Mi Mi Khin; Sutee Yoksan; Natth Bhamarapravati

    1999-01-01

    Assurance of identity and quantity is an indispensable part of quality control in the manufacture of vaccines. Dengue-1 PDK13, dengue-2 PDK53, dengue-3 PGMK30F3 and dengue-4 PDK48 in the live attenuated tetravalent dengue vaccine were assayed by identification and quantitation in a mosquito system (Toxorhynchites splendens). Each serotype of dengue virus was identified by dengue specific monoclonal antibodies in the indirect

  12. [Evaluation of immunity against Venezuelan equine encephalitis virus and dengue in the human population of San Carlos, the Almirante Padilla Island Municipality, Zulia State, Venezuela. 1996].

    PubMed

    Valero, N; Añez, F; Larreal, Y; Arias, J; Rodríguez, Z; Espina, L M

    2001-09-01

    The Insular Municipality of Almirante Padilla, historically, has been affected by Venezuelan Equine Encephalitis (VEE) epidemics, that have occurred cyclically in the Paez, Mara and Almirante Padilla Municipalities of the State of Zulia. During the last epidemic outbreak (1995), the studies reported a great number of cases of VEE in humans, based on epidemiologic-clinical diagnosis; occupying this municipality, the first place in the attack rate by the virus. At the same time, Dengue has been defined as an endemic illness affecting different regions, whose etiologic agent has previously circulated in the studied zone. In order to evaluate the immunity acquired against these viruses, a serological study was conducted in San Carlos Island. Two hundred and ten blood samples were obtained at random, among individuals of an age range between < 1 and 69 years, with and without antecedents of viral illness symptomatology at the moment of the epidemic outbreak, occurred in 1995. The samples were classified according to sex and age, and analyzed through the test of ELISA for specific IgG antibodies against the VEE and Dengue viruses. From the total of the samples processed, 116 (55.2%) were positive for VEE, affecting uniformly all age-groups with a slight masculine predominance. Likewise, 88 cases (41.9%) were determined positive for Dengue virus, affecting mainly the group ranging from 10 to 19 years. These results let us suggest that the epidemic outbreak occurred in 1995 at the Almirante Padilla Insular Municipality, had a double nature with both viruses being involved in the etiology of febrile cases. PMID:11552505

  13. Socially structured human movement shapes dengue transmission despite the diffusive effect of mosquito dispersal.

    PubMed

    Reiner, Robert C; Stoddard, Steven T; Scott, Thomas W

    2014-03-01

    For sexually and directly transmitted infectious diseases, social connections influence transmission because they determine contact between individuals. For pathogens that are indirectly transmitted by arthropod vectors, the movement of the vectors is thought to diminish the role of social connections. Results from a recent study of mosquito-borne dengue virus (DENV), however, indicate that human movement alone can explain significant spatial variation in urban transmission rates. Because movement patterns are structured by social ties, this result suggests that social proximity may be a good predictor of infection risk for DENV and other pathogens transmitted by the mosquito Aedes aegypti. Here we investigated the effect of socially structured movement on DENV transmission using a spatially explicit, agent-based transmission model. When individual movements overlap to a high degree within social groups we were able to recreate infection patterns similar to those detected in dengue-endemic, northeastern Peru. Our results are consistent with the hypothesis that social proximity drives fine-scale heterogeneity in DENV transmission rates, a result that was robust to the influence of mosquito dispersal. This heterogeneity in transmission caused by socially structured movements appeared to be hidden by the diffusive effect of mosquito dispersal in aggregated infection dynamics, which implies this heterogeneity could be present and active in real dengue systems without being easily noticed. Accounting for socially determined, overlapping human movements could substantially improve the efficiency and efficacy of dengue surveillance and disease prevention programs as well as result in more accurate estimates of important epidemiological quantities, such as R0. PMID:24593919

  14. Heterogeneous Feeding Patterns of the Dengue Vector, Aedes aegypti, on Individual Human Hosts in Rural Thailand

    PubMed Central

    Harrington, Laura C.; Fleisher, Andrew; Ruiz-Moreno, Diego; Vermeylen, Francoise; Wa, Chrystal V.; Poulson, Rebecca L.; Edman, John D.; Clark, John M.; Jones, James W.; Kitthawee, Sangvorn; Scott, Thomas W.

    2014-01-01

    Background Mosquito biting frequency and how bites are distributed among different people can have significant epidemiologic effects. An improved understanding of mosquito vector-human interactions would refine knowledge of the entomological processes supporting pathogen transmission and could reveal targets for minimizing risk and breaking pathogen transmission cycles. Methodology and principal findings We used human DNA blood meal profiling of the dengue virus (DENV) vector, Aedes aegypti, to quantify its contact with human hosts and to infer epidemiologic implications of its blood feeding behavior. We determined the number of different people bitten, biting frequency by host age, size, mosquito age, and the number of times each person was bitten. Of 3,677 engorged mosquitoes collected and 1,186 complete DNA profiles, only 420 meals matched people from the study area, indicating that Ae. aegypti feed on people moving transiently through communities to conduct daily business. 10–13% of engorged mosquitoes fed on more than one person. No biting rate differences were detected between high- and low-dengue transmission seasons. We estimate that 43–46% of engorged mosquitoes bit more than one person within each gonotrophic cycle. Most multiple meals were from residents of the mosquito collection house or neighbors. People ?25 years old were bitten less often than older people. Some hosts were fed on frequently, with three hosts bitten nine times. Interaction networks for mosquitoes and humans revealed biologically significant blood feeding hotspots, including community marketplaces. Conclusion and significance High multiple-feeding rates and feeding on community visitors are likely important features in the efficient transmission and rapid spread of DENV. These results help explain why reducing vector populations alone is difficult for dengue prevention and support the argument for additional studies of mosquito feeding behavior, which when integrated with a greater understanding of human behavior will refine estimates of risk and strategies for dengue control. PMID:25102306

  15. Germany tracks down source for dangerous E. coli outbreak

    NSDL National Science Digital Library

    Grinnell, Max

    Number of Rare E. Coli Cases in U.S. Rose Last Yearhttp://www.nytimes.com/2011/06/08/us/08food.htmlEconomic costs of E. Coli outbreakhttp://video.ca.msn.com/watch/video/economic-costs-of-e-coli-outbreak/16ifpbqesEU boosts E. Coli compensation offer for farmershttp://www.dw-world.de/dw/article/0,,15141284,00.htmlQ&A: E. Coli outbreakhttp://www.bbc.co.uk/news/health-13600144FightBac!http://www.fightbac.org/Today, Germany's head of their Center for Disease Control, Reinhard Burger said, "It's the bean sprouts." After 29 deaths, thousands taken ill, and produce bans that included Spanish cucumbers, tomatoes, and lettuce, it is believed that they have found the source of one of history's most dangerous outbreaks of E. Coli. Nine countries were affected by the outbreak, including Great Britain, Germany, Spain, Poland, and the United States. Russia recently placed a ban on all EU produce, thus adding an economic crisis to the medical crisis. In Germany, so many people were infected that hospitals struggled to cope, and because it was a new strain and extremely aggressive many health institutions were often offering conflicting advice. Thankfully, German officials seem to have located the source and the hope is that now the spread of this particular strain can be contained. Burger warns that the outbreak is "not yet over" as there "will be new cases coming up." However, with the source of this outbreak found, perhaps the EU, and the rest of the world, can focus on how to prevent these outbreaks in the future.The first link will take visitors to a news article on the recent announcement about bean sprouts from the New York Times. The second link will take visitors to another article from the New York Times which discusses the increasing number of rare E. Coli cases in the U.S. The third link will take visitors to a MSN video that examines the financial toll an E. Coli outbreak can take on produce farmers. The fourth link leads to an article from Deutsche Welle that discusses compensation the EU is offering farmers affected by the outbreak and subsequent produce bans. The fifth link is an informative Q&A from the BBC about E. Coli. The last link will lead visitors to the FightBac! website, a food safety initiative that educates consumers about reducing the risk of food borne illnesses.

  16. The May 2003 Extended Tornado Outbreak

    Microsoft Academic Search

    Thomas M. Hamill; Russell S. Schneider; Harold E. Brooks; Gregory S. Forbes; Howard B. Bluestein; Michael Steinberg; Daniel Meléndez; Randall M. Dole

    2005-01-01

    In May 2003 there was a very destructive extended outbreak of tornadoes across the central and eastern United States. More than a dozen tornadoes struck each day from 3 May to 11 May 2003. This outbreak caused 41 fatalities, 642 injuries, and approximately $829 million dollars of property damage. The outbreak set a record for most tornadoes ever reported in

  17. Coping with Stress during Infectious Disease Outbreaks

    MedlinePLUS

    · 1 Coping With Stress During Infectious Disease Outbreaks What You Should Know When you hear, read, or watch news about an outbreak of ... you may feel anxious and show signs of stress—even when the outbreak affects people far from ...

  18. Linking Oviposition Site Choice to Offspring Fitness in Aedes aegypti: Consequences for Targeted Larval Control of Dengue Vectors

    Microsoft Academic Search

    Jacklyn Wong; Amy C. Morrison; Steven T. Stoddard; Helvio Astete; Yui Yin Chu; Imaan Baseer; Thomas W. Scott

    2012-01-01

    BackgroundCurrent Aedes aegypti larval control methods are often insufficient for preventing dengue epidemics. To improve control efficiency and cost-effectiveness, some advocate eliminating or treating only highly productive containers. The population-level outcome of this strategy, however, will depend on details of Ae. aegypti oviposition behavior.Methodology\\/Principal FindingsWe simultaneously monitored female oviposition and juvenile development in 80 experimental containers located across 20 houses

  19. Dengue virus type 3 isolated from a fatal case with visceral complications induces enhanced proinflammatory responses and apoptosis of human dendritic cells.

    PubMed

    Silveira, Guilherme F; Meyer, Florencia; Delfraro, Adriana; Mosimann, Ana Luiza P; Coluchi, Norma; Vasquez, Cyntia; Probst, Christian M; Báfica, André; Bordignon, Juliano; Dos Santos, Claudia N Duarte

    2011-06-01

    A recent (2007 to 2009) dengue outbreak caused by dengue virus (DENV) in Paraguay presented unusual severe clinical outcomes associated with 50% mortality rates. Although it has been reported that inflammatory responses influence the severity of dengue virus infection (T. Pang, M. J. Cardosa, and M. G. Guzman, Immunol. Cell Biol. 85:43-45, 2007), there remains a paucity of information on virus-innate immunity interactions influencing clinical outcome. Using human dendritic cells from a major innate immune cell population as an in vitro model, we have investigated signature cytokine responses as well as infectivity-replicative profiles of DENV clinical isolates from either a nonfatal case of classical dengue fever (strain DENV3/290; isolated in Brazil in 2002) or a fatal case of dengue fever with visceral complications isolated in Paraguay in 2007 (strain DENV3/5532). Strain DENV3/5532 was found to display significantly higher replicative ability than DENV3/290 in monocyte-derived dendritic cells (mdDCs). In addition, compared to DENV3/290 results, mdDCs exposed to DENV3/5532 showed increased production of proinflammatory cytokines associated with higher rates of programmed cell death, as shown by annexin V staining. The observed phenotype was due to viral replication, and tumor necrosis factor alpha (TNF-?) appears to exert a protective effect on virus-induced mdDC apoptosis. These results suggest that the DENV3/5532 strain isolated from the fatal case replicates within human dendritic cells, modulating cell survival and synthesis of inflammatory mediators. PMID:21450836

  20. Outbreaks of salmonellosis in Minnesota (1998 through 2006) associated with frozen, microwaveable, breaded, stuffed chicken products.

    PubMed

    Smith, Kirk E; Medus, Carlota; Meyer, Stephanie D; Boxrud, David J; Leano, Fe; Hedberg, Craig W; Elfering, Kevin; Braymen, Craig; Bender, Jeffrey B; Danila, Richard N

    2008-10-01

    From 1998 through 2006, four outbreaks of salmonellosis associated with raw, frozen, microwaveable, breaded, prebrowned, stuffed chicken products were identified in Minnesota. In 1998, 33 Salmonella Typhimurium cases were associated with a single brand of Chicken Kiev. In 2005, four Salmonella Heidelberg cases were associated with a different brand and variety (Chicken Broccoli and Cheese). From 2005 to 2006, 27 Salmonella Enteritidis cases were associated with multiple varieties of product, predominately of the same brand involved in the 1998 outbreak. In 2006, three Salmonella Typhimurium cases were associated with the same brand of product involved in the 2005 Salmonella Heidelberg outbreak. The outbreak serotype and pulsed-field gel electrophoresis subtype of Salmonella were isolated from product in each outbreak. In these outbreaks, most individuals affected thought that the product was precooked due to its breaded and prebrowned nature, most used a microwave oven, most did not follow package cooking instructions, and none took the internal temperature of the cooked product. Similar to previous salmonellosis outbreaks associated with raw, breaded chicken nuggets or strips in Canada and Australia, inadequate labeling, consumer responses to labeling, and microwave cooking were the key factors in the occurrence of these outbreaks. Modification of labels, verification of cooking instructions by the manufacturer, and notifications to alert the public that these products contain raw poultry, implemented because of the first two outbreaks, did not prevent the other outbreaks. Microwave cooking is not recommended as a preparation method for these types of products, unless they are precooked or irradiated prior to sale. PMID:18939771

  1. Ebola Outbreak Killed 5000 Gorillas

    Microsoft Academic Search

    Magdalena Bermejo; José Domingo Rodríguez-Teijeiro; Germán Illera; Alex Barroso; Carles Vilà; Peter D. Walsh

    2006-01-01

    Over the past decade, the Zaire strain of Ebola virus (ZEBOV) has repeatedly emerged in Gabon and Congo. Each human outbreak has been accompanied by reports of gorilla and chimpanzee carcasses in neighboring forests, but both the extent of ape mortality and the causal role of ZEBOV have been hotly debated. Here, we present data suggesting that in 2002 and

  2. Outbreak Ethnography The Anthropologist's Toolkit

    E-print Network

    epidemiologist at Ebola seminar at Pasteur Institute, Paris 2004 The epidemiologist was asking the question during Ebola outbreaks are challenging and relatively unusual for most anthropologists; they challenged abilities to do the Ebola work, but we went into the field with a limited background on the history

  3. Invariant NKT Cell Response to Dengue Virus Infection in Human

    PubMed Central

    Matangkasombut, Ponpan; Chan-in, Wilawan; Opasawaschai, Anunya; Pongchaikul, Pisut; Tangthawornchaikul, Nattaya; Vasanawathana, Sirijitt; Limpitikul, Wannee; Malasit, Prida; Duangchinda, Thaneeya; Screaton, Gavin; Mongkolsapaya, Juthathip

    2014-01-01

    Background Dengue viral infection is a global health threat without vaccine or specific treatment. The clinical outcome varies from asymptomatic, mild dengue fever (DF) to severe dengue hemorrhagic fever (DHF). While adaptive immune responses were found to be detrimental in the dengue pathogenesis, the roles of earlier innate events remain largely uninvestigated. Invariant natural killer T (iNKT) cells represent innate-like T cells that could dictate subsequent adaptive response but their role in human dengue virus infection is not known. We hypothesized that iNKT cells play a role in human dengue infection. Methods Blood samples from a well-characterized cohort of children with DF, DHF, in comparison to non-dengue febrile illness (OFI) and healthy controls at various time points were studied. iNKT cells activation were analyzed by the expression of CD69 by flow cytometry. Their cytokine production was then analyzed after ?-GalCer stimulation. Further, the CD1d expression on monocytes, and CD69 expression on conventional T cells were measured. Results iNKT cells were activated during acute dengue infection. The level of iNKT cell activation associates with the disease severity. Furthermore, these iNKT cells had altered functional response to subsequent ex vivo stimulation with ?-GalCer. Moreover, during acute dengue infection, monocytic CD1d expression was also upregulated and conventional T cells also became activated. Conclusion iNKT cells might play an early and critical role in the pathogenesis of severe dengue viral infection in human. Targeting iNKT cells and CD1d serve as a potential therapeutic strategy for severe dengue infection in the future. PMID:24945350

  4. Dengue-associated hemophagocytic syndrome in a Japanese traveler: a case report.

    PubMed

    Kobayashi, Ken-ichiro; Hikone, Mayu; Sakamoto, Naoya; Iwabuchi, Sentaro; Kashiura, Masahiro; Takasaki, Tomohiko; Fujita, Hiroshi; Ohnishi, Kenji

    2015-01-01

    Hemophagocytic syndrome (HPS) can develop as a complication of dengue in rare cases, but its relationship with dengue is not well known. We report a case of dengue-associated HPS with liver involvement and coagulopathy. The patient, a Japanese female traveler who had recently returned from Thailand, had severe complications of dengue infection, but she recovered fully with symptomatic treatment. PMID:25159130

  5. Origins of Dengue Type 2 Viruses Associated with Increased Pathogenicity in the Americas

    Microsoft Academic Search

    Rebeca Rico-Hesse; Lisa M. Harrison; Rosa Alba Salas; Duilia Tovar; Ananda Nisalak; Celso Ramos; Jorge Boshell; Maria Teresa R. de Mesa; Rita M. R. Nogueira; Amélia Travassos da Rosa

    1997-01-01

    The recent emergence and spread of dengue hemorrhagic fever in the Americas have been a major source of concern. Efforts to control this disease are dependent on understanding the pathogenicity of dengue viruses and their transmission dynamics. Pathogenicity studies have been hampered by the lack ofin vitroorin vivomodels of severe dengue disease. Alternatively, molecular epidemiologic studies which associate certain dengue

  6. Dengue virus: molecular basis of cell entry and pathogenesis, 25–27 June 2003, Vienna, Austria

    Microsoft Academic Search

    Scott B. Halstead; Franz X. Heinz; A. D. T. Barrett; John T. Roehrig

    2005-01-01

    Multivalent dengue vaccines now in late stage development pose unique vaccine safety challenges in that primary or secondary vaccine failures might place vaccines at risk to antibody-dependent enhanced (ADE) wild-type dengue infections. This conference was organized to address this unique vaccine safety issue. New data were presented on the structure of dengue and other flaviviruses, the cellular receptors of dengue

  7. N-acetylcystein in dengue associated severe hepatitis

    PubMed Central

    Habaragamuwa, Buddhika Widyaratna Peiris; Dissanayaka, Palitha

    2014-01-01

    Although, N-acetylcystein (NAC) has shown benefit in non-acetaminophen related liver failure, it was not well studies in dengue associated severe hepatitis. We report a case of dengue hemorrhagic fever associated severe hepatitis (encephalopathy grade 2-drowsy and intermittent disorientation) treated with NAC resulted in good outcome without hepatic transplantation. PMID:24701072

  8. Increase in Imported Dengue, Germany, 2001–2002

    PubMed Central

    Schöneberg, Irene; Krause, Gérard; Claus, Hermann; Ammon, Andrea; Stark, Klaus

    2004-01-01

    Dengue fever is a reportable disease in Germany. Surveillance data from 2001 and 2002 were analyzed and compared to travel patterns. Imported dengue fever increased strongly in this time. Most infections were acquired in Southeast Asia, specifically Thailand. The 2002 epidemic in Brazil was also reflected in these data. PMID:15200827

  9. The GOOD-BYE TO DENGUE GAME: Debriefing Study

    ERIC Educational Resources Information Center

    Lennon, Jeffrey L.; Coombs, David W.

    2005-01-01

    This study examined the use of postgame debriefing of a health educational board game activity on dengue fever in a Filipino student population. The debriefing used a series of specific open-ended questions, exploring students' feelings about the game and game-related questionnaires, students' perceptions of important information about dengue from…

  10. Norovirus outbreak associated with a hotel in the west of Ireland, 2006.

    PubMed

    Michel, A; Fitzgerald, R; Whyte, D; Fitzgerald, A; Beggan, E; O'Connell, N; Greally, T

    2007-07-01

    An outbreak of gastrointestinal disease (nausea, vomiting or diarrhoea) occurred among a party of wedding guests, staff and other guests in a hotel in the west of Ireland, in October 2006. Upon notification, a multi-disciplinary outbreak control team was convened to investigate and control the outbreak. In all, 98 people were ascertained ill. The median duration of illness was 48 hours. The attack rate ranged between 48 and 85%. The hotel voluntarily notified health authorities and co-operated fully with investigation and control measures. Strict prevention and control measures were instituted promptly, including air ventilation, enhanced hand hygiene, isolation of cases, temporary "cooked food only", temporary alternative accommodation and specialised cleaning. Three cases of norovirus infection were laboratory-confirmed. There was no evidence of food- or water-borne transmission. Clinical and epidemiological findings indicated person-to-person transmission of norovirus. This report highlights the potential for large social gatherings to facilitate the spread of viral gastroenteritis by person-to-person transmission and via contaminated environment. Effective community management of this outbreak appears to have prevented its having an impact on local acute hospital services. The authors conclude that in addition to the existing national guidelines on the management of outbreaks of norovirus in healthcare settings, agreed guidelines for the management of norovirus outbreaks in the hotel and tourism industry are needed in Ireland. PMID:17991406

  11. Sequential Episodes of Dengue—Puerto Rico, 2005–2010

    PubMed Central

    Sharp, Tyler M.; Hunsperger, Elizabeth; Muñoz-Jordán, Jorge L.; Margolis, Harold S.; Tomashek, Kay M.

    2014-01-01

    Of 53,633 suspected dengue cases reported to a passive dengue surveillance system in Puerto Rico during 2005–2010, 949 individuals were reported on more than one occasion and 21 had laboratory-confirmed dengue on two separate occasions. Median time between illness episodes was 2.9 years (range: 62 days–5.3 years). Seventeen (81%) individuals with sequential episodes of dengue were male, and seven (33%) were adults. All 21 individuals experienced one episode and seven (33%) individuals experienced both episodes during a large epidemic that occurred in 2010. These observations show that heterotypic dengue virus immunity that protects against illness may have considerable variability but typically does not last longer than 3 years. PMID:24891464

  12. Modeling the impact on virus transmission of Wolbachia-mediated blocking of dengue virus infection of Aedes aegypti

    PubMed Central

    Ferguson, Neil M.; Kien, Duong Thi Hue; Clapham, Hannah; Aguas, Ricardo; Trung, Vu Tuan; Chau, Tran Nguyen Bich; Popovici, Jean; Ryan, Peter A.; O’Neill, Scott L.; McGraw, Elizabeth A.; Long, Vo Thi; Dui, Le Thi; Nguyen, Hoa L; Van Vinh Chau, Nguyen; Wills, Bridget; Simmons, Cameron P.

    2015-01-01

    Dengue is the most common arboviral infection of humans and a public health burden in over 100 countries. Aedes aegypti mosquitoes stably infected with strains of the intracellular bacterium Wolbachia are resistant to dengue virus (DENV) infection and are being tested in field trials. To mimic field conditions, we experimentally assessed the vector competence of A. aegypti carrying the Wolbachia strains wMel and wMelPop after challenge with viremic blood from dengue patients. We found that wMelPop conferred strong resistance to DENV infection of mosquito abdomen tissue and largely prevented disseminated infection. wMel conferred less resistance to infection of mosquito abdomen tissue, but importantly did reduce the prevalence of mosquitoes with infectious saliva. A mathematical model of DENV transmission incorporating the dynamics of viral infection within humans and mosquitoes was fitted to the data collected. Model predictions suggested that wMel would reduce the basic reproduction number, R0, of DENV transmission by 66–75%. Our results suggest that establishment of wMelPop-infected A. aegypti at high frequency in a dengue endemic setting would result in complete abatement of DENV transmission. Establishment of wMel-infected A. aegypti is also predicted to have a substantial effect on transmission that would be sufficient to eliminate dengue in low or moderate transmission settings, but may be insufficient to achieve complete control in settings where R0 is high. These findings develop a framework for selecting Wolbachia strains for field releases and for calculating their likely impact. PMID:25787763

  13. Modeling the impact on virus transmission of Wolbachia-mediated blocking of dengue virus infection of Aedes aegypti.

    PubMed

    Ferguson, Neil M; Hue Kien, Duong Thi; Clapham, Hannah; Aguas, Ricardo; Trung, Vu Tuan; Bich Chau, Tran Nguyen; Popovici, Jean; Ryan, Peter A; O'Neill, Scott L; McGraw, Elizabeth A; Long, Vo Thi; Dui, Le Thi; Nguyen, Hoa L; Vinh Chau, Nguyen Van; Wills, Bridget; Simmons, Cameron P

    2015-03-18

    Dengue is the most common arboviral infection of humans and is a public health burden in more than 100 countries. Aedes aegypti mosquitoes stably infected with strains of the intracellular bacterium Wolbachia are resistant to dengue virus (DENV) infection and are being tested in field trials. To mimic field conditions, we experimentally assessed the vector competence of A. aegypti carrying the Wolbachia strains wMel and wMelPop after challenge with viremic blood from dengue patients. We found that wMelPop conferred strong resistance to DENV infection of mosquito abdomen tissue and largely prevented disseminated infection. wMel conferred less resistance to infection of mosquito abdomen tissue, but it did reduce the prevalence of mosquitoes with infectious saliva. A mathematical model of DENV transmission incorporating the dynamics of viral infection in humans and mosquitoes was fitted to the data collected. Model predictions suggested that wMel would reduce the basic reproduction number, R0, of DENV transmission by 66 to 75%. Our results suggest that establishment of wMelPop-infected A. aegypti at a high frequency in a dengue-endemic setting would result in the complete abatement of DENV transmission. Establishment of wMel-infected A. aegypti is also predicted to have a substantial effect on transmission that would be sufficient to eliminate dengue in low or moderate transmission settings but may be insufficient to achieve complete control in settings where R0 is high. These findings develop a framework for selecting Wolbachia strains for field releases and for calculating their likely impact. PMID:25787763

  14. Inflammation of the external ear in acute chikungunya infection: Experience from the outbreak in Johor Bahru, Malaysia, 2008.

    PubMed

    Javelle, Emilie; Tiong, Tee Hua; Leparc-Goffart, Isabelle; Savini, Hélène; Simon, Fabrice

    2014-04-01

    The re-emerging invalidating chikungunya disease has recently extended to temperate areas. Other alphaviruses can also present with febrile arthalgias. Dengue virus transmitted by the same species of mosquitoes may cocirculate, leading to dual infections and concurrent epidemics. Although these diseases share similar clinical features, their prognoses considerably differ. Prominent and prolonged articular disorders are more consistent with chikungunya virus, whereas haemorrhages make the gravity of dengue infection. Specific symptoms are required, especially when diagnostic tests are not available or performable at a large scale. Indeed, early clinical suspicion of a vector-borne disease is crucial to isolate the first cases in the course of an outbreak, and discrimination between arboviruses help to optimal management of patients. No specific chikungunya clinical sign has been yet reported. We highlight here the high prevalence (about 25%) of acute ear redness in infected people during the 2008 chikungunya outbreak in Jahor Bahru in Malaysia. Nine consenting patients are more precisely described. Ear chondritis could be sensitive diagnostic criterion of the acute stage of chikungunya, every physician - even in occidental non endemic areas - should be aware of. PMID:24556566

  15. OutbreakTools: a new platform for disease outbreak analysis using the R software.

    PubMed

    Jombart, Thibaut; Aanensen, David M; Baguelin, Marc; Birrell, Paul; Cauchemez, Simon; Camacho, Anton; Colijn, Caroline; Collins, Caitlin; Cori, Anne; Didelot, Xavier; Fraser, Christophe; Frost, Simon; Hens, Niel; Hugues, Joseph; Höhle, Michael; Opatowski, Lulla; Rambaut, Andrew; Ratmann, Oliver; Soubeyrand, Samuel; Suchard, Marc A; Wallinga, Jacco; Ypma, Rolf; Ferguson, Neil

    2014-06-01

    The investigation of infectious disease outbreaks relies on the analysis of increasingly complex and diverse data, which offer new prospects for gaining insights into disease transmission processes and informing public health policies. However, the potential of such data can only be harnessed using a number of different, complementary approaches and tools, and a unified platform for the analysis of disease outbreaks is still lacking. In this paper, we present the new R package OutbreakTools, which aims to provide a basis for outbreak data management and analysis in R. OutbreakTools is developed by a community of epidemiologists, statisticians, modellers and bioinformaticians, and implements classes and methods for storing, handling and visualizing outbreak data. It includes real and simulated outbreak datasets. Together with a number of tools for infectious disease epidemiology recently made available in R, OutbreakTools contributes to the emergence of a new, free and open-source platform for the analysis of disease outbreaks. PMID:24928667

  16. OutbreakTools: A new platform for disease outbreak analysis using the R software

    PubMed Central

    Jombart, Thibaut; Aanensen, David M.; Baguelin, Marc; Birrell, Paul; Cauchemez, Simon; Camacho, Anton; Colijn, Caroline; Collins, Caitlin; Cori, Anne; Didelot, Xavier; Fraser, Christophe; Frost, Simon; Hens, Niel; Hugues, Joseph; Höhle, Michael; Opatowski, Lulla; Rambaut, Andrew; Ratmann, Oliver; Soubeyrand, Samuel; Suchard, Marc A.; Wallinga, Jacco; Ypma, Rolf; Ferguson, Neil

    2014-01-01

    The investigation of infectious disease outbreaks relies on the analysis of increasingly complex and diverse data, which offer new prospects for gaining insights into disease transmission processes and informing public health policies. However, the potential of such data can only be harnessed using a number of different, complementary approaches and tools, and a unified platform for the analysis of disease outbreaks is still lacking. In this paper, we present the new R package OutbreakTools, which aims to provide a basis for outbreak data management and analysis in R. OutbreakTools is developed by a community of epidemiologists, statisticians, modellers and bioinformaticians, and implements classes and methods for storing, handling and visualizing outbreak data. It includes real and simulated outbreak datasets. Together with a number of tools for infectious disease epidemiology recently made available in R, OutbreakTools contributes to the emergence of a new, free and open-source platform for the analysis of disease outbreaks. PMID:24928667

  17. Preparing for introduction of a dengue vaccine: recommendations from the 1st Dengue v2V Asia-Pacific Meeting.

    PubMed

    Lam, Sai Kit; Burke, Donald; Capeding, Maria Rosario; Chong, Chee Keong; Coudeville, Laurent; Farrar, Jeremy; Gubler, Duane; Hadinegoro, Sri Rezeki; Hanna, Jeffrey; Lang, Jean; Lee, Han Lim; Leo, Yee Sin; Luong, Chan Quang; Mahoney, Richard; McBride, John; Mendez-Galvan, Jorge; Ng, Lee Ching; Nimmannitya, Suchitra; Ooi, Eng Eong; Shepard, Donald; Smit, Jaco; Teyssou, Rémy; Thomas, Laurent; Torresi, Joseph; Vasconcelos, Pedro; Wirawan, Dewa Nyoman; Yoksan, Sutee

    2011-11-28

    Infection with dengue virus is a major public health problem in the Asia-Pacific region and throughout tropical and sub-tropical regions of the world. Vaccination represents a major opportunity to control dengue and several candidate vaccines are in development. Experts in dengue and in vaccine introduction gathered for a two day meeting during which they examined the challenges inherent to the introduction of a dengue vaccine into the national immunisation programmes of countries of the Asia-Pacific. The aim was to develop a series of recommendations to reduce the delay between vaccine licensure and vaccine introduction. Major recommendations arising from the meeting included: ascertaining and publicising the full burden and cost of dengue; changing the perception of dengue in non-endemic countries to help generate global support for dengue vaccination; ensuring high quality active surveillance systems and diagnostics; and identifying sustainable sources of funding, both to support vaccine introduction and to maintain the vaccination programme. The attendees at the meeting were in agreement that with the introduction of an effective vaccine, dengue is a disease that could be controlled, and that in order to ensure a vaccine is introduced as rapidly as possible, there is a need to start preparing now. PMID:21864627

  18. Phylogeny of Dengue and Chikungunya viruses in Al Hudayda governorate, Yemen.

    PubMed

    Ciccozzi, Massimo; Lo Presti, Alessandra; Cella, Eleonora; Giovanetti, Marta; Lai, Alessia; El-Sawaf, Gamal; Faggioni, Giovanni; Vescio, Fenicia; Al Ameri, Ranya; De Santis, Riccardo; Helaly, Ghada; Pomponi, Alice; Metwally, Dalia; Fantini, Massimo; Qadi, Hussein; Zehender, Gianguglielmo; Lista, Florigio; Rezza, Giovanni

    2014-10-01

    Yemen, which is located in the southwestern end of the Arabian Peninsula, is one of countries most affected by recurrent epidemics caused by emerging vector-borne viruses. Dengue virus (DENV) outbreaks have been reported with increasing frequency in several governorates since the year 2000, and the Chikungunya virus (CHIKV) has been also responsible of large outbreaks and it is now a major public health problem in Yemen. We report the results of the phylogenetic analysis of DENV-2 and CHIKV isolates (NS1 and E1 genes, respectively) detected in an outbreak occurred in Al-Hudayda in 2012. Estimates of the introduction date of CHIKV and DENV-2, and the phylogeographic analysis of DENV-2 are also presented. Phylogenetic analysis showed that the Yemen isolates of DENV belonged to the lineage 2 Cosmopolitan subtype, whereas CHIKV isolates from Yemen belonged to the ECSA genotype. All the CHIKV isolates from Yemen were statistically supported and dated back to the year 2010 (95% HPD: 2009-2011); these sequences showed an alanine in the aminoacid position 226 of the E1 protein. Phylogeographic analysis of DENV-2 virus showed that cluster 1, which included Yemen isolates, dated back to 2003 Burkina Faso strains (95% HPD 1999-2007). The Yemen, cluster dated back to 2011 (95% HPD 2009-2012). Our study sheds light on the global spatiotemporal dynamics of DENV-2 and CHIKV in Yemen. This study reinforces both the need to monitor the spread of CHIKV and DENV, and to apply significant measures for vector control. PMID:25183027

  19. Evaluation of dengue fever reports during an epidemic, Colombia

    PubMed Central

    Romero-Vega, Liliana; Pacheco, Oscar; de la Hoz-Restrepo, Fernando; Díaz-Quijano, Fredi Alexander

    2014-01-01

    OBJECTIVE To assess the validity of dengue fever reports and how they relate to the definition of case and severity. METHODS Diagnostic test assessment was conducted using cross-sectional sampling from a universe of 13,873 patients treated during the fifth epidemiological period in health institutions from 11 Colombian departments in 2013. The test under analyses was the reporting to the National Public Health Surveillance System, and the reference standard was the review of histories identified by active institutional search. We reviewed all histories of patients diagnosed with dengue fever, as well as a random sample of patients with febrile syndromes. The specificity and sensitivity of reports were estimated for this purpose, considering the inverse of the probability of being selected for weighting. The concordance between reporting and the findings of the active institutional search was calculated using Kappa statistics. RESULTS We included 4,359 febrile patients, and 31.7% were classified as compatible with dengue fever (17 with severe dengue fever; 461 with dengue fever and warning signs; 904 with dengue fever and no warning signs). The global sensitivity of reports was 13.2% (95%CI 10.9;15.4) and specificity was 98.4% (95%CI 97.9;98.9). Sensitivity varied according to severity: 12.1% (95%CI 9.3;14.8) for patients presenting dengue fever with no warning signs; 14.5% (95%CI 10.6;18.4) for those presenting dengue fever with warning signs, and 40.0% (95%CI 9.6;70.4) for those with severe dengue fever. Concordance between reporting and the findings of the active institutional search resulted in a Kappa of 10.1%. CONCLUSIONS Low concordance was observed between reporting and the review of clinical histories, which was associated with the low reporting of dengue fever compatible cases, especially milder cases.

  20. Dengue and Soluble Mediators of the Innate Immune System

    PubMed Central

    Espada-Murao, Lyre Anni; Morita, Kouichi

    2011-01-01

    Huge emphasis has been placed on the role of the adaptive immune system in dengue pathogenesis. Yet there is increasing evidence for the importance of the innate immune system in regulating dengue infection and possibly influencing the disease. This review focuses on the interplay between the innate immune system and dengue and highlights the role of soluble immunological mediators. Type I and type II interferons of the innate immune system demonstrate non-overlapping roles in dengue infection. Furthermore, while some IFN responses to dengue are protective, others may exert disease-related effects on the host. But aside from interferons, a number of cytokines have also been implicated in dengue pathogenesis. Our expanding knowledge of cytokines indicates that these soluble mediators act upon a complicated network of events to provoke the disease. This cytokine storm is generally attributed to massive T cell activation as an outcome of secondary infection. However, there is reason to believe that innate immune response-derived cytokines also have contributory effects, especially in the context of severe cases of primary dengue infection. Another less popular but interesting perspective on dengue pathogenesis is the effect of mosquito feeding on host immune responses and viral infection. Various studies have shown that soluble factors from vector saliva have the capacity to alter immune reactions and thereby influence pathogen transmission and establishment. Hence, modulation of the innate immune system at various levels of infection is a critical component of dengue disease. In the absence of an approved drug or vaccine for dengue, soluble mediators of the innate immune system could be a strategic foothold for developing anti-viral therapeutics and improving clinical management. PMID:22500137

  1. First Reported Chikungunya Fever Outbreak in the Republic of Congo, 2011

    PubMed Central

    Pastorino, Boris; Nougairede, Antoine; Thirion, Laurence; Mombouli, Jean-Vivien; Dimi, Yannick; Leparc-Goffart, Isabelle; Capobianchi, Maria Rosaria; Lepfoundzou, Amelia Dzia; de Lamballerie, Xavier

    2014-01-01

    Background Chikungunya is an Aedes -borne disease characterised by febrile arthralgia and responsible for massive outbreaks. We present a prospective clinical cohort study and a retrospective serological study relating to a CHIK outbreak, in the Republic of Congo in 2011. Methodology and Findings We analysed 317 suspected cases, of which 308 (97.2%) lived in the city of Brazzaville (66.6% in the South area). Amongst them, 37 (11.7%) were CHIKV+ve patients (i.e., biologically confirmed by a real-time RT-PCR assay), of whom 36 (97.3%) had fever, 22 (66.7%) myalgia and 32 (86.5%) arthralgia. All tested negative for dengue. The distribution of incident cases within Brazzaville districts was compared with CHIKV seroprevalence before the outbreak (34.4% in 517 blood donors), providing evidence for previous circulation of CHIKV. We applied a CHIK clinical score to 126 patients recruited within the two first day of illness (including 28 CHIKV+ves (22.2%)) with sensitivity (78.6%) and specificity (72.4%) values comparing with those of the referent study in Reunion Island. The negative predictive value was high (92%), but the positive predictive value (45%) indicate poor potential contribution to medical practice to identify CHIKV+ve patients in low prevalence outbreaks. However, the score allowed a slightly more accurate follow-up of the evolution of the outbreak than the criterion "fever+arthralgia". The complete sequencing of a Congolase isolate (Brazza_MRS1) demonstrated belonging to the East/Central/South African lineage and was further used for producing a robust genome-scale CHIKV phylogenetic analysis. Conclusions/Significance We describe the first Chikungunya outbreak declared in the Republic of Congo. The seroprevalence study conducted amongst blood donors before outbreak provided evidence for previous CHIKV circulation. We suggest that a more systematic survey of the entomological situation and of arbovirus circulation is necessary in Central Africa for better understanding the environmental, microbiological and sociological determinants of emergence. PMID:25541718

  2. Biological warfare training: infectious disease outbreak differentiation criteria.

    PubMed

    Noah, D L; Sobel, A L; Ostroff, S M; Kildew, J A

    1998-04-01

    The threat of biological terrorism and warfare may increase as the availability of weaponizable agents increases, the relative production costs of these agents decrease, and, most importantly, there exist terrorist groups willing to use them. Therefore, an important consideration during the current period of heightened surveillance for emerging infectious diseases is the ability to differentiate between natural and intentional outbreaks. Certain attributes of a disease outbreak, although perhaps not pathognomonic for a biological attack when considered singly, may combine to provide convincing evidence of intentional causation. These potentially differentiating criteria include proportion of combatants at risk, temporal patterns of illness onset, number of cases, clinical presentation, strain/variant, economic impact, geographic location, morbidity/mortality, antimicrobial resistance patterns, seasonal distribution, zoonotic potential, residual infectivity/toxicity, prevention/therapeutic potential, route of exposure, weather/climate conditions, incubation period, and concurrence with belligerent activities of potential adversaries. PMID:9575761

  3. Biological warfare training. Infectious disease outbreak differentiation criteria.

    PubMed

    Noah, D L; Sobel, A L; Ostroff, S M; Kildew, J A

    1999-01-01

    The threat of biological terrorism and warfare may increase as the availability of weaponizable agents increase, the relative production costs of these agents decrease, and, most importantly, there exist terrorist groups willing to use them. Therefore, an important consideration during the current emphasis of heightened surveillance for emerging infectious diseases is the capability to differentiate between natural and intentional outbreaks. Certain attributes of a disease outbreak, while perhaps not pathognomic for a biological attack when considered singly, may in combination with other attributes provide convincing evidence for intentional causation. These potentially differentiating criteria include proportion of combatants at risk, temporal patterns of illness onset, number of cases, clinical presentation, strain/variant, economic impact, geographic location, morbidity/mortality, antimicrobial resistance patterns, seasonal distribution, zoonotic potential, residual infectivity/toxicity, prevention/therapeutic potential, route of exposure, weather/climate conditions, incubation period, and concurrence with belligerent activities of potential adversaries. PMID:10681967

  4. Discovery of fifth serotype of dengue virus (DENV-5): A new public health dilemma in dengue control.

    PubMed

    Mustafa, M S; Rasotgi, V; Jain, S; Gupta, V

    2015-01-01

    Dengue fever is a re-emerging public health problem with two-fifths of the world population being at risk of infection. Till now, dengue fever was believed to be caused by four different serotypes. The fifth variant DENV-5 has been isolated in October 2013. This serotype follows the sylvatic cycle unlike the other four serotypes which follow the human cycle. The likely cause of emergence of the new serotype could be genetic recombination, natural selection and genetic bottlenecks. There is no indication of the presence of DENV-5 in India. Recent clinical trials with the promising Chimerivax tetravalent vaccine suffered a setback. Discovery of DENV-5 and more such sylvatic strains in future may further impede the Dengue Vaccine Initiative. Integrated Vector Management holds the key to sustainable dengue control. Further epidemiological and ecological studies are needed to detect additional sylvatic dengue strains. PMID:25609867

  5. Evaluation of Commercially Available Diagnostic Tests for the Detection of Dengue Virus NS1 Antigen and Anti-Dengue Virus IgM Antibody

    PubMed Central

    Hunsperger, Elizabeth A.; Yoksan, Sutee; Buchy, Philippe; Nguyen, Vinh Chau; Sekaran, Shamala Devi; Enria, Delia A.; Vazquez, Susana; Cartozian, Elizabeth; Pelegrino, Jose L.; Artsob, Harvey; Guzman, Maria G.; Olliaro, Piero; Zwang, Julien; Guillerm, Martine; Kliks, Susie; Halstead, Scott; Peeling, Rosanna W.; Margolis, Harold S.

    2014-01-01

    Commercially available diagnostic test kits for detection of dengue virus (DENV) non-structural protein 1 (NS1) and anti-DENV IgM were evaluated for their sensitivity and specificity and other performance characteristics by a diagnostic laboratory network developed by World Health Organization (WHO), the UNICEF/UNDP/World Bank/WHO Special Programme for Research and Training in Tropical Diseases (TDR) and the Pediatric Dengue Vaccine Initiative (PDVI). Each network laboratory contributed characterized serum specimens for the panels used in the evaluation. Microplate enzyme-linked immunosorbent assay (ELISA) and rapid diagnostic test (RDT formats) were represented by the kits. Each ELISA was evaluated by 2 laboratories and RDTs were evaluated by at least 3 laboratories. The reference tests for IgM anti-DENV were laboratory developed assays produced by the Armed Forces Research Institute for Medical Science (AFRIMS) and the Centers for Disease Control and Prevention (CDC), and the NS1 reference test was reverse transcriptase polymerase chain reaction (RT-PCR). Results were analyzed to determine sensitivity, specificity, inter-laboratory and inter-reader agreement, lot-to-lot variation and ease-of-use. NS1 ELISA sensitivity was 60–75% and specificity 71–80%; NS1 RDT sensitivity was 38–71% and specificity 76–80%; the IgM anti-DENV RDTs sensitivity was 30–96%, with a specificity of 86–92%, and IgM anti-DENV ELISA sensitivity was 96–98% and specificity 78–91%. NS1 tests were generally more sensitive in specimens from the acute phase of dengue and in primary DENV infection, whereas IgM anti-DENV tests were less sensitive in secondary DENV infections. The reproducibility of the NS1 RDTs ranged from 92-99% and the IgM anti-DENV RDTs from 88–94%. PMID:25330157

  6. Specific genetic markers for detecting subtypes of dengue virus serotype-2 in isolates from the states of Oaxaca and Veracruz, Mexico

    PubMed Central

    Gardella-Garcia, Catalina E; Perez-Ramirez, Gerardo; Navarrete-Espinosa, Joel; Cisneros, Alejandro; Jimenez-Rojas, Fabiola; Ramírez-Palacios, Luis R; Rosado-Leon, Rocio; Camacho-Nuez, Minerva; Munoz, Maria de L

    2008-01-01

    Background Dengue (DEN) is an infectious disease caused by the DEN virus (DENV), which belongs to the Flavivirus genus in the family Flaviviridae. It has a (+) sense RNA genome and is mainly transmitted to humans by the vector mosquito Aedes aegypti. Dengue fever (DF) and dengue hemorrhagic fever (DHF) are caused by one of four closely related virus serotypes (DENV-1, DENV-2, DENV-3 and DENV-4). Epidemiological and evolutionary studies have indicated that host and viral factors are involved in determining disease outcome and have proved the importance of viral genotype in causing severe epidemics. Host immune status and mosquito vectorial capacity are also important influences on the severity of infection. Therefore, an understanding of the relationship between virus variants with altered amino acids and high pathogenicity will provide more information on the molecular epidemiology of DEN. Accordingly, knowledge of the DENV serotypes and genotypes circulating in the latest DEN outbreaks around the world, including Mexico, will contribute to understanding DEN infections. Results 1. We obtained 88 isolates of DENV, 27 from Oaxaca and 61 from Veracruz. 2. Of these 88 isolates, 16 were serotype 1; 62 serotype 2; 7 serotype 3; and 2 serotype 4. One isolate had 2 serotypes (DENV-2 and -1). 3. Partial nucleotide sequences of the genes encoding C- prM (14 sequences), the NS3 helicase domain (7 sequences), the NS5 S-adenosyl methionine transferase domain (7 sequences) and the RNA-dependent RNA polymerase (RdRp) domain (18 sequences) were obtained. Phylogenetic analysis showed that DENV-2 isolates belonged to the Asian/American genotype. In addition, the Asian/American genotype was divided into two clusters, one containing the isolates from 2001 and the other the isolates from 2005–2006 with high bootstrap support of 94%. Conclusion DENV-2 was the predominant serotype in the DF and DHF outbreak from 2005 to 2006 in Oaxaca State as well as in the 2006 outbreak in Veracruz State, with the Asian/American genotype prevalent in both states. Interestingly, DENV-1 and DENV-2 were the only serotypes related to DHF cases. In contrast, DENV-3 and DENV-4 were poorly represented according to epidemiological data reported in Mexico. We found that isoleucine was replaced by valine at residue 106 of protein C in the isolates from these 2005–2006 outbreaks and in those from the 1997, 1998 and 2001 outbreaks in the Caribbean islands. We suggested that this amino acid change may be used as a signature for isolates arising in the Caribbean islands and pertaining to the Asian/American genotype. Other amino acid changes are specific for the Asian/American, Asian and American strains. PMID:18625078

  7. Souvenirs: Investigating a Disease Outbreak

    NSDL National Science Digital Library

    Janet Yagoda Shagam (RhizoTech; Biology)

    0000-00-00

    Starting with a case study based on the outbreak of a pulmonary disease in Southwest US, the interactions between human behavior, exposure, and confusing clinical symptoms are highlighted. As we search for the cause, these complications reflect real life difficulty in making diagnoses. The real questions extend beyond what disease has been contracted to cascading effects on the society we live in. * weigh the personal risks of exposure to a potentially fatal virus

  8. A novel dengue fever (DF) and dengue haemorrhagic fever (DHF) analysis using artificial neural network (ANN).

    PubMed

    Ibrahim, Fatimah; Taib, Mohd Nasir; Abas, Wan Abu Bakar Wan; Guan, Chan Chong; Sulaiman, Saadiah

    2005-09-01

    Dengue fever (DF) is an acute febrile viral disease frequently presented with headache, bone or joint and muscular pains, and rash. A significant percentage of DF patients develop a more severe form of disease, known as dengue haemorrhagic fever (DHF). DHF is the complication of DF. The main pathophysiology of DHF is the development of plasma leakage from the capillary, resulting in haemoconcentration, ascites, and pleural effusion that may lead to shock following defervescence of fever. Therefore, accurate prediction of the day of defervescence of fever is critical for clinician to decide on patient management strategy. To date, no known literature describes of any attempt to predict the day of defervescence of fever in DF patients. This paper describes a non-invasive prediction system for predicting the day of defervescence of fever in dengue patients using artificial neural network. The developed system bases its prediction solely on the clinical symptoms and signs and uses the multilayer feed-forward neural networks (MFNN). The results show that the proposed system is able to predict the day of defervescence in dengue patients with 90% prediction accuracy. PMID:15925426

  9. Outbreaks of zygomycosis in hospitals.

    PubMed

    Antoniadou, A

    2009-10-01

    Zygomycosis refers to a group of uncommon and frequently fatal mycoses caused by fungi of the class Zygomycetes, the organisms of which are usually found in decaying organic matter. Disease can be transmitted by the inhalation of spores or by direct inoculation on disrupted skin or mucosa. For rare diseases such as zygomycosis, two or more cases occurring in a short time should be investigated as a probable epidemic. Twelve hospital outbreaks and two pseudoepidemics caused by Zygomycetes have been cited in the English literature. The first epidemic was recorded in 1977 and the last in 2008. Outbreaks have been reported in the USA, the UK and elsewhere in Europe. Cases have included cutaneous, disseminated, pulmonary and rhinocerebral disease. Species identified have included Rhizopus arrhizus, Rhizopus rhizopodiformis, Rhizopus microsporus, Rhizopus spp., Absidia corymbifera and Rhizomucor pusillius. Sources of infection have included Elastoplast adhesive bandage rolls, ventilation systems, wooden tongue depressors, karaya (plant-derived adhesive) ostomy bags, and water damage to a linen store and patient shower room. Patients have included cardiosurgery patients, renal transplant recipients, orthopaedic patients, adult leukaemia patients, intensive care unit neonates, immunocompromised haematology patients, and burn unit patients. Although zygomycosis outbreaks in the hospital environment are infrequent, a high index of suspicion should exist if necrotic lesions appear in proximity to a postoperative wound. Direct tissue examination and tissue culture and histopathology must be routinely performed. PMID:19754759

  10. Acceptance of Vaccinations in Pandemic Outbreaks: A Discrete Choice Experiment

    PubMed Central

    Determann, Domino; Korfage, Ida J.; Lambooij, Mattijs S.; Bliemer, Michiel; Richardus, Jan Hendrik; Steyerberg, Ewout W.; de Bekker-Grob, Esther W.

    2014-01-01

    Background Preventive measures are essential to limit the spread of new viruses; their uptake is key to their success. However, the vaccination uptake in pandemic outbreaks is often low. We aim to elicit how disease and vaccination characteristics determine preferences of the general public for new pandemic vaccinations. Methods In an internet-based discrete choice experiment (DCE) a representative sample of 536 participants (49% participation rate) from the Dutch population was asked for their preference for vaccination programs in hypothetical communicable disease outbreaks. We used scenarios based on two disease characteristics (susceptibility to and severity of the disease) and five vaccination program characteristics (effectiveness, safety, advice regarding vaccination, media attention, and out-of-pocket costs). The DCE design was based on a literature review, expert interviews and focus group discussions. A panel latent class logit model was used to estimate which trade-offs individuals were willing to make. Results All above mentioned characteristics proved to influence respondents’ preferences for vaccination. Preference heterogeneity was substantial. Females who stated that they were never in favor of vaccination made different trade-offs than males who stated that they were (possibly) willing to get vaccinated. As expected, respondents preferred and were willing to pay more for more effective vaccines, especially if the outbreak was more serious (€6–€39 for a 10% more effective vaccine). Changes in effectiveness, out-of-pocket costs and in the body that advises the vaccine all substantially influenced the predicted uptake. Conclusions We conclude that various disease and vaccination program characteristics influence respondents’ preferences for pandemic vaccination programs. Agencies responsible for preventive measures during pandemics can use the knowledge that out-of-pocket costs and the way advice is given affect vaccination uptake to improve their plans for future pandemic outbreaks. The preference heterogeneity shows that information regarding vaccination needs to be targeted differently depending on gender and willingness to get vaccinated. PMID:25057914

  11. The 2007 Rift Valley fever outbreak in Sudan.

    PubMed

    Hassan, Osama Ahmed; Ahlm, Clas; Sang, Rosemary; Evander, Magnus

    2011-09-01

    Rift Valley fever (RVF) is a neglected, emerging, mosquito-borne disease with severe negative impact on human and animal health and economy. RVF is caused by RVF virus (RVFV) affecting humans and a wide range of animals. The virus is transmitted through bites from mosquitoes and exposure to viremic blood, body fluids, or tissues of infected animals. During 2007 a large RVF outbreak occurred in Sudan with a total of 747 confirmed human cases including 230 deaths (case fatality 30.8%); although it has been estimated 75,000 were infected. It was most severe in White Nile, El Gezira, and Sennar states near to the White Nile and the Blue Nile Rivers. Notably, RVF was not demonstrated in livestock until after the human cases appeared and unfortunately, there are no records or reports of the number of affected animals or deaths. Ideally, animals should serve as sentinels to prevent loss of human life, but the situation here was reversed. Animal contact seemed to be the most dominant risk factor followed by animal products and mosquito bites. The Sudan outbreak followed an unusually heavy rainfall in the country with severe flooding and previous studies on RVF in Sudan suggest that RVFV is endemic in parts of Sudan. An RVF outbreak results in human disease, but also large economic loss with an impact beyond the immediate influence on the directly affected agricultural producers. The outbreak emphasizes the need for collaboration between veterinary and health authorities, entomologists, environmental specialists, and biologists, as the best strategy towards the prevention and control of RVF. PMID:21980543

  12. Genotypic and Epidemiologic Trends of Norovirus Outbreaks in the United States, 2009 to 2013

    PubMed Central

    Barclay, Leslie; Gregoricus, Nicole; Shirley, S. Hannah; Lee, David

    2014-01-01

    Noroviruses are the leading cause of epidemic acute gastroenteritis in the United States. From September 2009 through August 2013, 3,960 norovirus outbreaks were reported to CaliciNet. Of the 2,895 outbreaks with a known transmission route, person-to-person and food-borne transmissions were reported for 2,425 (83.7%) and 465 (16.1%) of the outbreaks, respectively. A total of 2,475 outbreaks (62.5%) occurred in long-term care facilities (LTCF), 389 (9.8%) in restaurants, and 227 (5.7%) in schools. A total of 435 outbreaks (11%) were typed as genogroup I (GI) and 3,525 (89%) as GII noroviruses. GII.4 viruses caused 2,853 (72%) of all outbreaks, of which 94% typed as either GII.4 New Orleans or GII.4 Sydney. In addition, three non-GII.4 viruses, i.e., GII.12, GII.1, and GI.6, caused 528 (13%) of all outbreaks. Several non-GII.4 genotypes (GI.3, GI.6, GI.7, GII.3, GII.6, and GII.12) were significantly more associated with food-borne transmission (odds ratio, 1.9 to 7.1; P < 0.05). Patients in LTCF and people ?65 years of age were at higher risk for GII.4 infections than those in other settings and with other genotypes (P < 0.05). Phylogeographic analysis identified three major dispersions from two geographic locations that were responsible for the GI.6 outbreaks from 2011 to 2013. In conclusion, our data demonstrate the cyclic emergence of new (non-GII.4) norovirus strains, and several genotypes are more often associated with food-borne outbreaks. These surveillance data can be used to improve viral food-borne surveillance and to help guide studies to develop and evaluate targeted prevention methods such as norovirus vaccines, antivirals, and environmental decontamination methods. PMID:24172151

  13. Contributing and Terminating Factors of a Large RSV Outbreak in an Adult Hematology and Transplant Unit

    PubMed Central

    Aichinger, Elisabeth; Schnitzler, Paul; Heeg, Klaus; Dederer, Wolfgang; Benz, Michael A.; Buda, Silke; Dreger, Peter; Egerer, Gerlinde; Eisenbach, Christoph; Geis, Steffen; Haas, Walter; Ho, Anthony D.; Lehners, Nicola; Neben, Kai; Pfaff, Guenter; Prifert, Christiane; Schwertz, Rainer; Thalheimer, Markus; Wagner-Wiening, Christiane; Weißbrich, Benedikt; Buchholz, Udo

    2014-01-01

    Background: In January 2012, an increase of respiratory syncytial virus (RSV) infections on an adult hematology and transplant unit in a German university hospital was detected. We investigated the outbreak to assess its timing and extent and to identify risk factors for transmission. Methods: We tested and typed patient samples pro- and retrospectively for RSV. We conducted a cohort and a case-control study. A confirmed outbreak case had laboratory-diagnosed, nosocomially-acquired RSV infection. Possible outbreak cases had pneumonia but were not laboratory-confirmed. Results: Of 53 outbreak cases, 36 (68%) were confirmed and 17 (32%) possible. Retrospective testing and chart review dated the beginning of the outbreak to November 2011. Patients with community-acquired RSV infection were identified when the community epidemic began in January 2012. In multivariable analysis (controlling for contact with medical personnel, hygiene behaviour and age) patients with active social behaviour were more at risk for RSV infection (odds ratio 23.8, 95% confidence interval, 1.3 to 434.9; p-value, 0.03). Confirmed outbreak cases were more likely than controls to have been accomodated together with a confirmed or possible case before their onset of illness (OR 9.3, 95%CI: 2.1-85.1; p<0.001). Control measures, including isolation of every patient in the unit, initiated until the end of January terminated the outbreak. Conclusions: Epidemiological investigations revealed co-accomodation with a case-patient and active social behaviour as likely risk factors for RSV infection. Awareness of and vigorous testing for respiratory viruses in immunosuppressed hospitalised patients is necessary to timely detect cases with outbreak potential. Isolation of patients with respiratory infectious illnesses is crucial to prevent the continuation or occurrence of outbreaks. PMID:25687181

  14. Neutralizing antibodies respond to a bivalent dengue DNA vaccine or/and a recombinant bivalent antigen.

    PubMed

    Zhang, Zhi-Shan; Weng, Yu-Wei; Huang, Hai-Long; Zhang, Jian-Ming; Yan, Yan-Sheng

    2015-02-01

    There is currently no effective vaccine to prevent dengue infection, despite the existence of multiple studies on potential methods of immunization. The aim of the present study was to explore the effect of DNA and/or recombinant protein on levels of neutralizing antibodies. For this purpose, envelope domain IIIs of dengue serotypes 1 and 2 (DEN-1/2)were spliced by a linker (Gly?Gly?Ser?Gly?Ser)3 and cloned into the prokaryotic expression plasmid pET30a (+) and eukaryotic vector pcDNA3.1 (+). The chimeric bivalent protein was expressed in Escherichia coli, and one?step purification by high?performance liquid chromatography was conducted. Protein expression levels of the DNA plasmid were tested in BHK?21 cells by indirect immunofluorescent assay. In order to explore a more effective immunization strategy and to develop neutralizing antibodies against the two serotypes, mice were inoculated with recombinant bivalent protein, the DNA vaccine, or the two given simultaneously. Presence of the specific antibodies was tested by ELISA and the presence of the neutralizing antibodies was determined by plaque reduction neutralization test. Results of the analysis indicated that the use of a combination of DNA and protein induced significantly higher titers of neutralizing antibodies against either DEN?1 or DEN?2 (1:64.0 and 1:76.1, respectively) compared with the DNA (1:24.7 and 1:26.9, DEN?1 and DEN?2, respectively) or the recombinant protein (1:34.9 and 1:45.3 in DEN?1 and DEN?2, respectively). The present study demonstrated that the combination of recombinant protein and DNA as an immunization strategy may be an effective method for the development of a vaccine to prevent dengue virus infection. PMID:25371092

  15. Preventing Hantavirus Pulmonary Syndrome (HPS)

    MedlinePLUS

    ... Materials and Media Publications and Links Outbreaks Yosemite National Park Case Count Maps Epi Curves FAQ: U.S. Visitors to Yosemite FAQ: Non-U.S. Visitors to Yosemite History of HPS File ... Content source: Centers for Disease Control and Prevention National Center for Emerging and Zoonotic Infectious Diseases (NCEZID) ...

  16. Heart and Skeletal Muscle Are Targets of Dengue Virus Infection

    PubMed Central

    Salgado, Doris Martha; Eltit, José Miguel; Mansfield, Keith; Panqueba, César; Castro, Dolly; Vega, Martha Rocio; Xhaja, Kris; Schmidt, Diane; Martin, Katherine J.; Allen, Paul D.; Rodriguez, Jairo Antonio; Dinsmore, Jonathan H.; López, José Rafael; Bosch, Irene

    2010-01-01

    Background Dengue fever is one of the most significant re-emerging tropical diseases, despite our expanding knowledge of the disease, viral tropism is still not known to target heart tissues or muscle. Methods A prospective pediatric clinical cohort of 102 dengue hemorrhagic fever patients from Colombia, South America, was followed for 1 year. Clinical diagnosis of myocarditis was routinely performed. Electrocardiograph and echocardiograph analysis were performed to confirm those cases. Immunohistochemistry for detection of dengue virus and inflammatory markers was performed on autopsied heart tissue. In vitro studies of human striated skeletal fibers (myotubes) infected with dengue virus were used as a model for myocyte infection. Measurements of intracellular Ca2+ concentration as well as immunodetection of dengue virus and inflammation markers in infected myotubes were performed. Results Eleven children with dengue hemorrhagic fever presented with symptoms of myocarditis. Widespread viral infection of the heart, myocardial endothelium, and cardiomyocytes, accompanied by inflammation was observed in 1 fatal case. Immunofluorescence confocal microscopy showed that myotubes were infected by dengue virus and had increased expression of the inflammatory genes and protein IP-10. The infected myotubes also had increases in intracellular Ca2+ concentration. Conclusions Vigorous infection of heart tissues in vivo and striated skeletal cells in vitro are demonstrated. Derangements of Ca2+ storage in the infected cells may directly contribute to the presentation of myocarditis in pediatric patients. PMID:20032806

  17. Cost and disease burden of Dengue in Cambodia

    PubMed Central

    2010-01-01

    Background Dengue is endemic in Cambodia (pop. estimates 14.4 million), a country with poor health and economic indicators. Disease burden estimates help decision makers in setting priorities. Using recent estimates of dengue incidence in Cambodia, we estimated the cost of dengue and its burden using disability adjusted life years (DALYs). Methods Recent population-based cohort data were used to calculate direct and productive costs, and DALYs. Health seeking behaviors were taken into account in cost estimates. Specific age group incidence estimates were used in DALYs calculation. Results The mean cost per dengue case varied from US$36 - $75 over 2006-2008 respectively, resulting in an overall annual cost from US$3,327,284 in 2008 to US$14,429,513 during a large epidemic in 2007. Patients sustain the highest share of costs by paying an average of 78% of total costs and 63% of direct medical costs. DALY rates per 100,000 individuals ranged from 24.3 to 100.6 in 2007-2008 with 80% on average due to premature mortality. Conclusion Our analysis confirmed the high societal and individual family burden of dengue. Total costs represented between 0.03 and 0.17% of Gross Domestic Product. Health seeking behavior has a major impact on costs. The more accurate estimate used in this study will better allow decision makers to account for dengue costs particularly among the poor when balancing the benefits of introducing a potentially effective dengue vaccine. PMID:20807395

  18. PH 412 Syllabus 2013 Control and Prevention of

    E-print Network

    Chisholm, Rex L.

    , methods for evaluating interventions and control efforts, culture, politics, and economics. We for communicable diseases 2. discuss specific methods used to investigate outbreaks, control disease, and prevent become familiar with a few of the scientific citations referenced in the outbreak publication and review

  19. Multi-level analyses of spatial and temporal determinants for dengue infection

    PubMed Central

    Vanwambeke, Sophie O; van Benthem, Birgit HB; Khantikul, Nardlada; Burghoorn-Maas, Chantal; Panart, Kamolwan; Oskam, Linda; Lambin, Eric F; Somboon, Pradya

    2006-01-01

    Background Dengue is a mosquito-borne viral infection that is now endemic in most tropical countries. In Thailand, dengue fever/dengue hemorrhagic fever is a leading cause of hospitalization and death among children. A longitudinal study among 1750 people in two rural and one urban sites in northern Thailand from 2001 to 2003 studied spatial and temporal determinants for recent dengue infection at three levels (time, individual and household). Methods Determinants for dengue infection were measured by questionnaire, land-cover maps and GIS. IgM antibodies against dengue were detected by ELISA. Three-level multi-level analysis was used to study the risk determinants of recent dengue infection. Results Rates of recent dengue infection varied substantially in time from 4 to 30%, peaking in 2002. Determinants for recent dengue infection differed per site. Spatial clustering was observed, demonstrating variation in local infection patterns. Most of the variation in recent dengue infection was explained at the time-period level. Location of a person and the environment around the house (including irrigated fields and orchards) were important determinants for recent dengue infection. Conclusion We showed the focal nature of asymptomatic dengue infections. The great variation of determinants for recent dengue infection in space and time should be taken into account when designing local dengue control programs. PMID:16420702

  20. Is dengue a disease of poverty? A systematic review.

    PubMed

    Mulligan, Kate; Dixon, Jenna; Joanna Sinn, Chi-Ling; Elliott, Susan J

    2015-02-01

    Policy prescriptions for combating dengue fever tend to focus on addressing environmental and social conditions of poverty. However, while poverty has long been considered a determinant of dengue, the research evidence for such a relationship is not well established. Results of a systematic review of the research literature designed to identify and assess the current state of the empirical evidence for the dengue-poverty link reveal a mixed story. Of 260 peer-reviewed articles referencing dengue-poverty relationships, only 12 English-language studies empirically assessed these relationships. Our analysis covering various social and economic conditions of poverty showed no clear associations with dengue rates. While nine of the 12 studies demonstrated some positive associations between measures of dengue and poverty (measured inconsistently through income, education, structural housing condition, overcrowding, and socioeconomic status), nine also presented null results and five with negative results. Of the five studies relating to access to water and sanitation, four reported null associations. Income and physical housing conditions were more consistently correlated with dengue outcomes than other poverty indicators. The small size of this sample, and the heterogeneity of measures and scales used to capture conditions of poverty, make it difficult to assess the strength and consistency of associations between various poverty indicators and dengue outcomes. At present, the global body of eligible English-language peer-reviewed literature investigating dengue-poverty relationships is too small to support a definitive relationship. We conclude that more research, particularly using standardized measures of both outcomes and indicators, is needed to support evidence-informed policies and approaches. PMID:25546339

  1. Intrinsic Unpredictability of Epidemic Outbreaks on Networks

    E-print Network

    Iwai, Junya

    2013-01-01

    It has been known that epidemic outbreaks in the SIR model on networks are described by phase transitions. Despite the similarity with percolation transitions, whether an epidemic outbreak occurs or not cannot be predicted with probability one in the thermodynamic limit. We elucidate its mechanism by deriving a simple Langevin equation that captures an essential aspect of the phenomenon. We also calculate the probability of epidemic outbreaks near the transition point.

  2. Waterborne disease outbreaks, 1986-1988.

    PubMed

    Levine, W C; Stephenson, W T; Craun, G F

    1990-03-01

    From 1986 to 1988, 24 states and Puerto Rico reported 50 outbreaks of illness due to water that people intended to drink, affecting 25,846 persons. The protozoal parasite Giardia lamblia was the agent most commonly implicated in outbreaks, as it has been for the last 10 years; many of these outbreaks were associated with ingestion of chlorinated but unfiltered surface water. Shigella sonnei was the most commonly implicated bacterial pathogen; in outbreaks caused by this pathogen, water supplies were found to be contaminated with human waste. Cryptosporidium contamination of a chlorinated, filtered public water supply caused the largest outbreak during this period, affecting an estimated 13,000 persons. A large multistate outbreak caused by commercially produced ice made from contaminated well water caused illness with Norwalk-like virus among an estimated 5,000 persons. The first reported outbreak of chronic diarrhea of unknown cause associated with drinking untreated well water occurred in 1987. Twenty-six outbreaks due to recreational water use were also reported, including outbreaks of Pseudomonas dermatitis associated with the use of hot tubs or whirlpools, and swimming-associated shigellosis, giardiasis, and viral illness. Although the total number of reported water-related outbreaks has been declining in recent years, the few large outbreaks due to Cryptosporidium, Norwalk-like agent, Shigella sonnei, and Giardia lamblia caused more cases of illness in 1987 than have been reported to the Water-Related Disease Outbreak Surveillance System for any other year since CDC and the Environmental Protection Agency began tabulating these data in 1971. PMID:2156147

  3. New vaccines for neglected parasitic diseases and dengue.

    PubMed

    Beaumier, Coreen M; Gillespie, Portia M; Hotez, Peter J; Bottazzi, Maria Elena

    2013-09-01

    Neglected tropical diseases (NTDs) are a significant source of morbidity and socioeconomic burden among the world's poor. Virtually all of the 2.4 billion people who live on less than $2 per d, more than a third of the world's population, are at risk for these debilitating NTDs. Although chemotherapeutic measures exist for many of these pathogens, they are not sustainable countermeasures on their own because of rates of reinfection, risk of drug resistance, and inconsistent maintenance of drug treatment programs. Preventative and therapeutic NTD vaccines are needed as long-term solutions. Because there is no market in the for-profit sector of vaccine development for these pathogens, much of the effort to develop vaccines is driven by nonprofit entities, mostly through product development partnerships. This review describes the progress of vaccines under development for many of the NTDs, with a specific focus on those about to enter or that are currently in human clinical trials. Specifically, we report on the progress on dengue, hookworm, leishmaniasis, schistosomiasis, Chagas disease, and onchocerciasis vaccines. These products will be some of the first with specific objectives to aid the world's poorest populations. PMID:23578479

  4. Reduction in dengue cases observed during mass control of Aedes (Stegomyia) in street catch basins in an endemic urban area in Colombia.

    PubMed

    Ocampo, Clara B; Mina, Neila Julieth; Carabalí, Mabel; Alexander, Neal; Osorio, Lyda

    2014-04-01

    Dengue incidence continues to increase globally and, in the absence of an efficacious vaccine, prevention strategies are limited to vector control. It has been suggested that targeting the most productive breeding sites instead of all water-holding containers could be a cost-effective vector control strategy. We sought to identify and continuously control the most productive Aedes (Stegomyia) breeding site in an endemic urban area in Colombia and followed the subsequent incidence of dengue. In the urban area of Guadalajara de Buga, southwestern Colombia, potential breeding sites inside and outside houses were first characterized, and local personnel trained to assess their productivity based on the pupae/person index. Simultaneously, training and monitoring were implemented to improve the dengue case surveillance system. Entomological data and insecticide resistance studies were used to define the targeted intervention. Then, a quasi-experimental design was used to assess the efficacy of the intervention in terms of the positivity index of the targeted and non- targeted breeding sites, and the impact on dengue cases. Street catch basins (storm drains) were the potential breeding site most frequently found containing Aedes immature stages in the baseline (58.3% of 108). Due to the high resistance to temephos (0% mortality after 24h), the intervention consisted of monthly application of pyriproxyfen in all the street catch basins (n=4800). A significant decrease in catch basins positivity for Aedes larvae was observed after each monthly treatment (p<0.001). Over the intervention period, a reduction in the dengue incidence in Buga was observed (rate ratio 0.19, 95% CI 0.12-0.30, p<0.0001) after adjusting for autocorrelation and controlling with a neighboring town, Palmira, This study highlights the importance of street catch basins as Aedes breeding sites and suggests that their targeted control could help to decrease dengue transmission in such areas. PMID:24388794

  5. Ebola virus disease: history, epidemiology and outbreaks.

    PubMed

    Weyer, Jacqueline; Grobbelaar, Antoinette; Blumberg, Lucille

    2015-05-01

    Over the past 40 years, sporadic Ebola virus disease (EVD) outbreaks have occurred mostly in the central African region. In March 2014, an outbreak of EVD was recognized in Guinea which would become the most significant outbreak of haemorrhagic fever in Africa to date. The outbreak started in Guinea and rapidly spread to Liberia and Sierra Leone, claiming thousands of lives. Many questions still remain regarding the ecology of Ebola viruses, but it is believed that contact with infected bushmeat is an important risk factor for initial spill over of the virus into the human population. At present, there is still no registered prophylaxis or curative biologicals against EVD. PMID:25896751

  6. Concurrent Infection with Dengue and Malaria: An Unusual Presentation

    PubMed Central

    Mushtaq, Mohsin Bin; Qadri, Mehmood I.; Rashid, Aaliya

    2013-01-01

    Dengue and malaria are both endemic in South Asia and represent a major public health burden in this region. Though there have been some case reports of concurrent infection with dengue and malaria, yet there are only few cases of such infections reported from South Asia. Here, we present a case of a young male returning from a dengue endemic area who tested positive for the virus along with Plasmodium vivax and Plasmodium falciparum. In view of the severity of coinfection (Epelboin et al., 2012), overlapping symptoms, and a challenging obscurity of diagnosis, a multidimensional diagnostic approach is suggested. PMID:23606854

  7. Current neurological observations and complications of dengue virus infection.

    PubMed

    Solbrig, Marylou V; Perng, Guey-Chuen

    2015-06-01

    Dengue, a mosquito-borne flavivirus and fastest growing tropical disease in the world, has experienced an explosion of neurologic case reports and series in recent years. Now dengue is a frequent or leading cause of encephalitis in some endemic regions, is estimated to infect one in six tourists returning from the tropics, and has been proven to have local transmission within the continental USA. High documentation of neurologic disease in recent years reflects increases in overall cases, enhanced clinical awareness and advances in diagnostics. Neurological aspects of dengue virus, along with epidemiology, treatment, and vaccine progress, are presented. PMID:25877545

  8. Structural insights into the neutralization mechanism of a higher primate antibody against dengue virus

    PubMed Central

    Cockburn, Joseph JB; Navarro Sanchez, M Erika; Goncalvez, Ana P; Zaitseva, Elena; Stura, Enrico A; Kikuti, Carlos M; Duquerroy, Stéphane; Dussart, Philippe; Chernomordik, Leonid V; Lai, Ching-Juh; Rey, Felix A

    2012-01-01

    The four serotypes of dengue virus (DENV-1 to -4) cause the most important emerging viral disease. Protein E, the principal viral envelope glycoprotein, mediates fusion of the viral and endosomal membranes during virus entry and is the target of neutralizing antibodies. However, the epitopes of strongly neutralizing human antibodies have not been described despite their importance to vaccine development. The chimpanzee Mab 5H2 potently neutralizes DENV-4 by binding to domain I of E. The crystal structure of Fab 5H2 bound to E from DENV-4 shows that antibody binding prevents formation of the fusogenic hairpin conformation of E, which together with in-vitro assays, demonstrates that 5H2 neutralizes by blocking membrane fusion in the endosome. Furthermore, we show that human sera from patients recovering from DENV-4 infection contain antibodies that bind to the 5H2 epitope region on domain I. This study, thus, provides new information and tools for effective vaccine design to prevent dengue disease. PMID:22139356

  9. Complete genome sequencing and evolutionary analysis of Indian isolates of Dengue virus type 2

    SciTech Connect

    Dash, Paban Kumar, E-mail: pabandash@rediffmail.com; Sharma, Shashi; Soni, Manisha; Agarwal, Ankita; Parida, Manmohan; Rao, P.V.Lakshmana

    2013-07-05

    Highlights: •Complete genome of Indian DENV-2 was deciphered for the first time in this study. •The recent Indian DENV-2 revealed presence of many unique amino acid residues. •Genotype shift (American to Cosmopolitan) characterizes evolution of DENV-2 in India. •Circulation of a unique clade of DENV-2 in South Asia was identified. -- Abstract: Dengue is the most important arboviral infection of global public health significance. It is now endemic in most parts of the South East Asia including India. Though Dengue virus type 2 (DENV-2) is predominantly associated with major outbreaks in India, complete genome information of Indian DENV-2 is not available. In this study, the full-length genome of five DENV-2 isolates (four from 2001 to 2011 and one from 1960), from different parts of India was determined. The complete genome of the Indian DENV-2 was found to be 10,670 bases long with an open reading frame coding for 3391 amino acids. The recent Indian DENV-2 (2001–2011) revealed a nucleotide sequence identity of around 90% and 97% with an older Indian DENV-2 (1960) and closely related Sri Lankan and Chinese DENV-2 respectively. Presence of unique amino acid residues and non-conservative substitutions in critical amino acid residues of major structural and non-structural proteins was observed in recent Indian DENV-2. Selection pressure analysis revealed positive selection in few amino acid sites of the genes encoding for structural and non-structural proteins. The molecular phylogenetic analysis based on comparison of both complete coding region and envelope protein gene with globally diverse DENV-2 viruses classified the recent Indian isolates into a unique South Asian clade within Cosmopolitan genotype. A shift of genotype from American to Cosmopolitan in 1970s characterized the evolution of DENV-2 in India. Present study is the first report on complete genome characterization of emerging DENV-2 isolates from India and highlights the circulation of a unique clade in South Asia.

  10. Phylogenetic history demonstrates two different lineages of dengue type 1 virus in Colombia

    PubMed Central

    2010-01-01

    Background Dengue Fever is one of the most important viral re-emergent diseases affecting about 50 million people around the world especially in tropical and sub-tropical countries. In Colombia, the virus was first detected in the earliest 70's when the disease became a major public health concern. Since then, all four serotypes of the virus have been reported. Although most of the huge outbreaks reported in this country have involved dengue virus serotype 1 (DENV-1), there are not studies about its origin, genetic diversity and distribution. Results We used 224 bp corresponding to the carboxyl terminus of envelope (E) gene from 74 Colombian isolates in order to reconstruct phylogenetic relationships and to estimate time divergences. Analyzed DENV-1 Colombian isolates belonged to the formerly defined genotype V. Only one virus isolate was clasified in the genotype I, likely representing a sole introduction that did not spread. The oldest strains were closely related to those detected for the first time in America in 1977 from the Caribbean and were detected for two years until their disappearance about six years later. Around 1987, a split up generated 2 lineages that have been evolving separately, although not major aminoacid changes in the analyzed region were found. Conclusion DENV-1 has been circulating since 1978 in Colombia. Yet, the phylogenetic relationships between strains isolated along the covered period of time suggests that viral strains detected in some years, although belonging to the same genotype V, have different recent origins corresponding to multiple re-introduction events of viral strains that were circulating in neighbor countries. Viral strains used in the present study did not form a monophyletic group, which is evidence of a polyphyletic origin. We report the rapid spread patterns and high evolution rate of the different DENV-1 lineages. PMID:20836894

  11. Cell Phone-Based System (Chaak) for Surveillance of Immatures of Dengue Virus Mosquito Vectors

    PubMed Central

    LOZANO–FUENTES, SAUL; WEDYAN, FADI; HERNANDEZ–GARCIA, EDGAR; SADHU, DEVADATTA; GHOSH, SUDIPTO; BIEMAN, JAMES M.; TEP-CHEL, DIANA; GARCÍA–REJÓN, JULIÁN E.; EISEN, LARS

    2014-01-01

    Capture of surveillance data on mobile devices and rapid transfer of such data from these devices into an electronic database or data management and decision support systems promote timely data analyses and public health response during disease outbreaks. Mobile data capture is used increasingly for malaria surveillance and holds great promise for surveillance of other neglected tropical diseases. We focused on mosquito-borne dengue, with the primary aims of: 1) developing and field-testing a cell phone-based system (called Chaak) for capture of data relating to the surveillance of the mosquito immature stages, and 2) assessing, in the dengue endemic setting of Mérida, México, the cost-effectiveness of this new technology versus paper-based data collection. Chaak includes a desktop component, where a manager selects premises to be surveyed for mosquito immatures, and a cell phone component, where the surveyor receives the assigned tasks and captures the data. Data collected on the cell phone can be transferred to a central database through different modes of transmission, including near-real time where data are transferred immediately (e.g., over the Internet) or by first storing data on the cell phone for future transmission. Spatial data are handled in a novel, semantically driven, geographic information system. Compared with a pen-and-paper-based method, use of Chaak improved the accuracy and increased the speed of data transcription into an electronic database. The cost-effectiveness of using the Chaak system will depend largely on the up-front cost of purchasing cell phones and the recurring cost of data transfer over a cellular network. PMID:23926788

  12. Epidemiological Risk Factors Associated with High Global Frequency of Inapparent Dengue Virus Infections

    PubMed Central

    Grange, Laura; Simon-Loriere, Etienne; Sakuntabhai, Anavaj; Gresh, Lionel; Paul, Richard; Harris, Eva

    2014-01-01

    Dengue is a major international public health concern, and the number of outbreaks has escalated greatly. Human migration and international trade and travel are constantly introducing new vectors and pathogens into novel geographic areas. Of particular interest is the extent to which dengue virus (DENV) infections are subclinical or inapparent. Not only may such infections contribute to the global spread of DENV by human migration, but also seroprevalence rates in naïve populations may be initially high despite minimal numbers of detectable clinical cases. As the probability of severe disease is increased in secondary infections, populations may thus be primed, with serious public health consequences following introduction of a new serotype. In addition, pre-existing immunity from inapparent infections may affect vaccine uptake, and the ratio of clinically apparent to inapparent infection could affect the interpretation of vaccine trials. We performed a literature search for inapparent DENV infections and provide an analytical review of their frequency and associated risk factors. Inapparent rates were highly variable, but “inapparent” was the major outcome of infection in all prospective studies. Differences in the epidemiological context and type of surveillance account for much of the variability in inapparent infection rates. However, one particular epidemiological pattern was shared by four longitudinal cohort studies: the rate of inapparent DENV infections was positively correlated with the incidence of disease the previous year, strongly supporting an important role for short-term heterotypic immunity in determining the outcome of infection. Primary and secondary infections were equally likely to be inapparent. Knowledge of the extent to which viruses from inapparent infections are transmissible to mosquitoes is urgently needed. Inapparent infections need to be considered for their impact on disease severity, transmission dynamics, and vaccine efficacy and uptake. PMID:24966859

  13. Radiotelemetry reveals differences in individual movement patterns between outbreak and non-outbreak

    E-print Network

    Lorch, Patrick D.

    -outbreak Mormon cricket populations PATRICK D. LORCH1 , GREGORY A. SWORD2 , DARRYL T. GWYNNE3 and GERALD L migrations during outbreaks. 2. Flightless Mormon crickets (Anabrus simplex) were the focus of this study. They are a katydid species that forms large, dense, mobile groups (migratory bands) during outbreak periods, eating

  14. The Sublethal Effects of the Entomopathic Fungus Leptolegnia chapmanii on Some Biological Parameters of the Dengue Vector Aedes aegypti

    PubMed Central

    Pelizza, S.A.; Scorsetti, A.C.; Tranchida, M.C.

    2013-01-01

    The mosquito Aedes aegypti (L.) (Diptera: Culicidae) is the primary vector of dengue in the Americas. The use of chemical insecticides is recommended during outbreaks of dengue in order to reduce the number of adult mosquitoes; however, because Ae. aegypti is highly synanthropic, the use of insecticides in densely populated areas is a dangerous practice. Leptolegnia chapmanii Seymour (Straminipila: Peronosporomycetes) is an entomopathogenic microorganism that has demonstrated marked pathogenicity toward the larvae of a number of mosquito species, with little or no effect on non-target insects. Therefore, the purpose of this study was to determine the sublethal effects of L. chapmanii on fecundity, number of gonotrophic cycles, fertility, and relationship between wing length and fecundity in Ae. aegypti females. Ae. aegypti females that survived infection with L. chapmanii laid fewer eggs, had a smaller number of gonotrophic cycles, had shorter wings, and were less fertile than controls. This is the first study on the sublethal effects experienced by specimens of Ae. aegypti that survived infection with zoospores of L. chapmanii. Although field studies should be carried out, the results obtained in this study are encouraging because the high and rapid larval mortality caused by L. chapmanii coupled with the reduction of reproductive capacity in Ae. aegypti females seem to cause a significant reduction in the number of adults in the mid and long term, thereby reducing the health risks associated with Ae. aegypti. PMID:23901823

  15. [Update on outbreaks reported from neonatal intensive care units: Serratia marcescens, Klebsiella pneumoniae, Acinetobacter baumannii, and Pseudomonas aeruginosa].

    PubMed

    Kraus-Haas, Martina; Mielke, Martin; Simon, Arne

    2015-03-01

    In terms of the unique risk profile, the clinical course of nosocomial infections, and the most prevalent bacterial pathogens, literature on outbreaks of potentially pathogenic bacteria on neonatal intensive care units (NICUs) needs to be analyzed separately from reports derived from other intensive care units. With the purpose of updating important information for those involved in outbreak management and fostering preventive efforts, this article summarizes the results of a systematic literature analysis, referring to an earlier publication by Gastmeier et al. This review focuses on NICU outbreaks caused by Serratia marcescens, Klebsiella pneumoniae, Acinetobacter baumannii, and Pseudomonas aeruginosa. PMID:25665889

  16. Waterborne outbreak of viral gastroenteritis.

    PubMed

    Kukkula, M; Arstila, P; Klossner, M L; Maunula, L; Bonsdorff, C H; Jaatinen, P

    1997-01-01

    A waterborne epidemic took place in a Finnish municipality in April 1994. Some 1500-3000 people, i.e. 25-50% of the population, had symptomatic acute gastroenteritis. Laboratory findings confirmed adenovirus, a Norwalk-like agent, small round viruses (SRV), and group A and C rotaviruses as causative agents, Norwalk virus being the main cause of the outbreak. The epidemic was most probably associated with contaminated drinking water. The groundwater well, situated in the embankment of a river, was contaminated by polluted river water during the spring flood. A back flow from the river to the well had occurred via a forgotten drainage pipe. PMID:9360259

  17. Development of a transmission model for dengue virus

    PubMed Central

    2013-01-01

    Background Dengue virus (DENV) research has historically been hampered by the lack of a susceptible vertebrate transmission model. Recently, there has been progress towards such models using several varieties of knockout mice, particularly those deficient in type I and II interferon receptors. Based on the critical nature of the type I interferon response in limiting DENV infection establishment, we assessed the permissiveness of a mouse strain with a blunted type I interferon response via gene deficiencies in interferon regulatory factors 3 and 7 (IRF3/7 ?/? ?/?) with regards to DENV transmission success. We investigated the possibility of transmission to the mouse by needle and infectious mosquito, and subsequent transmission back to mosquito from an infected animal during its viremic period. Methods Mice were inoculated subcutaneously with non-mouse adapted DENV-2 strain 1232 and serum was tested for viral load and cytokine production each day. Additionally, mosquitoes were orally challenged with the same DENV-2 strain via artificial membrane feeder, and then allowed to forage or naïve mice. Subsequently, we determined acquisition potential by allowing naïve mosquitoes on forage on exposed mice during their viremic period. Results Both needle inoculation and infectious mosquito bite(s) resulted in 100% infection. Significant differences between these groups in viremia on the two days leading to peak viremia were observed, though no significant difference in cytokine production was seen. Through our determination of transmission and acquisition potentials, the transmission cycle (mouse-to mosquito-to mouse) was completed. We confirmed that the IRF3/7 ?/? ?/? mouse supports DENV replication and is competent for transmission experiments, with the ability to use a non-mouse adapted DENV-2 strain. A significant finding of this study was that this IRF3/7 ?/? ?/? mouse strain was able to be infected by and transmit virus to mosquitoes, thus providing means to replicate the natural transmission cycle of DENV. Conclusion As there is currently no approved vaccine for DENV, public health monitoring and a greater understanding of transmission dynamics leading to outbreak events are critical. The further characterization of DENV using this model will expand knowledge of key entomological, virological and immunological components of infection establishment and transmission events. PMID:23617898

  18. Retrospective search for dengue vector mosquito Aedes albopictus in areas visited by a German traveler who contracted dengue in Japan.

    PubMed

    Kobayashi, Mutsuo; Komagata, Osamu; Yonejima, Mayuko; Maekawa, Yoshihide; Hirabayashi, Kimio; Hayashi, Toshihiko; Nihei, Naoko; Yoshida, Masahiro; Tsuda, Yoshio; Sawabe, Kyoko

    2014-09-01

    A German traveler developed dengue fever in late August 2013, following a direct flight from Germany. Autochthonous dengue virus (DENV) infection has not been reported in Japan. To evaluate the risk of autochthonous DENV transmission in Japan, the authors performed a retrospective search of the five areas visited by the German patient to determine the population density of dengue vector mosquito, Aedes albopictus. The annual mean temperature of each area was higher than 12°C, which is considered suitable for the establishment of A. albopictus populations. Our retrospective search revealed the population density of A. albopictus to be high in the urban areas of Japan. PMID:25063022

  19. Epidemiology of dengue fever in Hanoi from 2002 to 2010 and its meteorological determinants

    PubMed Central

    Minh An, Dao Thi; Rocklöv, Joacim

    2014-01-01

    Background Dengue fever (DF) is a growing public health problem in Vietnam. The disease burden in Vietnam has been increasing for decades. In Hanoi, in contrast to many other regions, extrinsic drivers such as weather have not been proved to be predictive of disease frequency, which limits the usefulness of such factors in an early warning system. Aims The purpose of this research was to review the epidemiology of DF transmission and investigate the role of weather factors contributing to occurrence of DF cases. Methods Monthly data from Hanoi (2002–2010) were used to test the proposed model. Descriptive time-series analysis was conducted. Stepwise multivariate linear regression analysis assuming a negative binomial distribution was established through several models. The predictors used were lags of 1–3 months previous observations of mean rainfall, mean temperature, DF cases, and their interactions. Results Descriptive analysis showed that DF occurred annually and seasonally with an increasing time trend in Hanoi. The annual low occurred from December to March followed by a gradual increase from April to July with a peak in September, October. The amplitude of the annual peak varied between years. Statistically significant relationships were estimated at lag 1–3 with rainfall, autocorrelation, and their interaction while temperature was estimated as influential at lag 3 only. For these relationships, the final model determined a correlation of 92% between predicted number of dengue cases and the observed dengue disease frequencies. Conclusions Although the model performance was good, the findings suggest that other fo