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Sample records for dengue fever mosquito

  1. Dengue fever (image)

    Science.gov (United States)

    Dengue fever, or West Nile fever, is a mild viral illness transmitted by mosquitoes which causes fever, ... second exposure to the virus can result in Dengue hemorrhagic fever, a life-threatening illness.

  2. Origin of the dengue fever mosquito, Aedes aegypti, in California.

    Science.gov (United States)

    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.

  3. Dengue hemorrhagic fever

    Science.gov (United States)

    ... that is infected with the virus. The mosquito Aedes aegypti is the main species that spreads this ... especially if you have had dengue fever before. Prevention Because there is no way to prevent dengue ...

  4. Identification of New Protein Interactions between Dengue Fever Virus and Its Hosts, Human and Mosquito

    Science.gov (United States)

    Mairiang, Dumrong; Zhang, Huamei; Sodja, Ann; Murali, Thilakam; Suriyaphol, Prapat; Malasit, Prida; Limjindaporn, Thawornchai; Finley, Russell L.

    2013-01-01

    The four divergent serotypes of dengue virus are the causative agents of dengue fever, dengue hemorrhagic fever and dengue shock syndrome. About two-fifths of the world's population live in areas where dengue is prevalent, and thousands of deaths are caused by the viruses every year. Dengue virus is transmitted from one person to another primarily by the yellow fever mosquito, Aedes aegypti. Recent studies have begun to define how the dengue viral proteins interact with host proteins to mediate viral replication and pathogenesis. A combined analysis of these studies, however, suggests that many virus-host protein interactions remain to be identified, especially for the mosquito host. In this study, we used high-throughput yeast two-hybrid screening to identify mosquito and human proteins that physically interact with dengue proteins. We tested each identified host protein against the proteins from all four serotypes of dengue to identify interactions that are conserved across serotypes. We further confirmed many of the interactions using co-affinity purification assays. As in other large-scale screens, we identified some previously detected interactions and many new ones, moving us closer to a complete host – dengue protein interactome. To help summarize and prioritize the data for further study, we combined our interactions with other published data and identified a subset of the host-dengue interactions that are now supported by multiple forms of evidence. These data should be useful for understanding the interplay between dengue and its hosts and may provide candidates for drug targets and vector control strategies. PMID:23326450

  5. Identification of new protein interactions between dengue fever virus and its hosts, human and mosquito.

    Directory of Open Access Journals (Sweden)

    Dumrong Mairiang

    Full Text Available The four divergent serotypes of dengue virus are the causative agents of dengue fever, dengue hemorrhagic fever and dengue shock syndrome. About two-fifths of the world's population live in areas where dengue is prevalent, and thousands of deaths are caused by the viruses every year. Dengue virus is transmitted from one person to another primarily by the yellow fever mosquito, Aedes aegypti. Recent studies have begun to define how the dengue viral proteins interact with host proteins to mediate viral replication and pathogenesis. A combined analysis of these studies, however, suggests that many virus-host protein interactions remain to be identified, especially for the mosquito host. In this study, we used high-throughput yeast two-hybrid screening to identify mosquito and human proteins that physically interact with dengue proteins. We tested each identified host protein against the proteins from all four serotypes of dengue to identify interactions that are conserved across serotypes. We further confirmed many of the interactions using co-affinity purification assays. As in other large-scale screens, we identified some previously detected interactions and many new ones, moving us closer to a complete host - dengue protein interactome. To help summarize and prioritize the data for further study, we combined our interactions with other published data and identified a subset of the host-dengue interactions that are now supported by multiple forms of evidence. These data should be useful for understanding the interplay between dengue and its hosts and may provide candidates for drug targets and vector control strategies.

  6. Effectiveness of Mosquito Trap with Sugar Fermented Attractant to the Vector of Dengue Hemorrhagic Fever

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    Endang Puji Astuti

    2011-06-01

    Full Text Available Aedes aegypti is the main vector of dengue fever that is still become health problem in the world. Various control efforts has been done at several areas through chemically or naturally control. Developing mosquitoes trapping tool is an alternative method to control mosquitoes besides insecticides utilization. This laboratorium research utilize sugar fermented process to yield CO2 as one of attractan to mosquito. Production of ethanol and CO2 can be yielded from anaerob sugar fermentation proccess (without O2 by khamir Saccharomyces cerevisiae activities. The trapped mosquitoes was observed up to 48 hours exposure, the highest average of mosquito trapped is on solution treatment with yeast 1 gram (43.2% and 40 gr sugar (48.4%. The highest effectivity of trapping tool both inside or outside was on the 14th day. There were declained amount of trapped mosquitos on 16th and 18th days. This laboratorium research has described that trapping tool with sugar fermented solution were effective to control population of dengue vector.

  7. Mosquitoes, models, and dengue.

    Science.gov (United States)

    Lifson, A R

    1996-05-04

    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

  8. Dengue fever

    Science.gov (United States)

    ... the mosquito Aedes aegypti , which is found in tropic and subtropic regions. This area includes parts of: ... encephalitis, St. Louis encephalitis, tick-borne encephalitis, Kyasanur forest disease, Alkhurma hemorrhagic fever, Zika). In: Bennett JE, ...

  9. Dengue Fever Testing

    Science.gov (United States)

    ... AACC products and services. Advertising & Sponsorship: Policy | Opportunities Dengue Fever Testing Share this page: Was this page helpful? Also known as: Dengue Fever Antibodies; Dengue Fever Virus Formal name: Dengue ...

  10. Rhombencephalitis associated with Dengue fever.

    Science.gov (United States)

    Verma, Rajesh; Bharti, Kavita; Mehta, Mannan; Bansod, Amrit

    2016-05-01

    Dengue infection is gradually disseminating throughout the world in alarming proportions. It is a arbovirus infection,transmitted by aedes mosquitoes. It is a multi-systemic disorder associated with varied neurological complications. There is increased trend of development of neurological complications in dengue fever. The neurological complications arising due to dengue infection can be categorized into central and neuromuscular complications. The central nervous system disorders reported with dengue fever are encephalopathy,encephalitis and myelitis.Here we report a case of rhombencephalitis associated with dengue fever. The literature does not mention rhombencephalitis occurring with dengue illness.

  11. Infection of Mosquito Cells (C6/36) by Dengue-2 Virus Interferes with Subsequent Infection by Yellow Fever Virus.

    Science.gov (United States)

    Abrao, Emiliana Pereira; da Fonseca, Benedito Antônio Lopes

    2016-02-01

    Dengue is one of the most important diseases caused by arboviruses in the world. Yellow fever is another arthropod-borne disease of great importance to public health that is endemic to tropical regions of Africa and the Americas. Both yellow fever and dengue viruses are flaviviruses transmitted by Aedes aegypti mosquitoes, and then, it is reasonable to consider that in a given moment, mosquito cells could be coinfected by both viruses. Therefore, we decided to evaluate if sequential infections of dengue and yellow fever viruses (and vice-versa) in mosquito cells could affect the virus replication patterns. Using immunofluorescence and real-time PCR-based replication assays in Aedes albopictus C6/36 cells with single or sequential infections with both viruses, we demonstrated the occurrence of viral interference, also called superinfection exclusion, between these two viruses. Our results show that this interference pattern is particularly evident when cells were first infected with dengue virus and subsequently with yellow fever virus (YFV). Reduction in dengue virus replication, although to a lower extent, was also observed when C6/36 cells were initially infected with YFV followed by dengue virus infection. Although the importance that these findings have on nature is unknown, this study provides evidence, at the cellular level, of the occurrence of replication interference between dengue and yellow fever viruses and raises the question if superinfection exclusion could be a possible explanation, at least partially, for the reported lack of urban yellow fever occurrence in regions where a high level of dengue transmission occurs.

  12. Dengue and dengue haemorrhagic fever: Indian perspective

    Indian Academy of Sciences (India)

    U C Chaturvedi; Rachna Nagar

    2008-11-01

    The relationship of this country with dengue has been long and intense. The first recorded epidemic of clinically dengue-like illness occurred at Madras in 1780 and the dengue virus was isolated for the first time almost simultaneously in Japan and Calcutta in 1943–1944. After the first virologically proved epidemic of dengue fever along the East Coast of India in 1963–1964, it spread to allover the country. The first full-blown epidemic of the severe form of the illness, the dengue haemorrhagic fever/dengue shock syndrome occurred in North India in 1996. Aedes aegypti is the vector for transmission of the disease. Vaccines or antiviral drugs are not available for dengue viruses; the only effective way to prevent epidemic degure fever/dengue haemorrhagic fever (DF/DHF) is to control the mosquito vector, Aedes aegypti and prevent its bite. This country has few virus laboratories and some of them have done excellent work in the area of molecular epidemiology, immunopathology and vaccine development. Selected work done in this country on the problems of dengue is presented here.

  13. Bioefficacy of Mentha piperita essential oil against dengue fever mosquito Aedes aegypti L

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    Sarita Kumar

    2011-04-01

    Conclusions: The peppermint essential oil is proved to be efficient larvicide and repellent against dengue vector. Further studies are needed to identify the possible role of oil as adulticide, oviposition deterrent and ovicidal agent. The isolation of active ingredient from the oil could help in formulating strategies for mosquito control.

  14. Larvicidal and repellent effect of some Tribulus terrestris L., (Zygophyllaceae extracts against the dengue fever mosquito, Aedes aegypti (Diptera: Culicidae

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    Tarek M.Y. El-Sheikh

    2016-01-01

    Full Text Available Aedes aegypti transmits etiologic agents of yellow fever and dengue. Vaccine for dengue virus is not available and vector control is essential to minimize dengue incidence. The larvicidal and repellent effect of the crude ethanol, acetone and petroleum ether extract leaves of Tribulus terrestris, against 3rd instar larvae and adults of mosquito, Ae. aegypti the vector of dengue fever was evaluated. The efficacy of petroleum ether extract seemed to be more effective with LC50 64.6 ppm followed by acetone extract with LC50 173.2 ppm and finally ethanolic extract with LC50 376.4 ppm. Moreover, the acetone and petroleum ether extracts exerted a highly delayed toxic effect on the pupae and adults resulted from treated larvae, where the pupal mortality was 57.1% and 100% at concentrations 400 and 100 ppm, respectively. Also, the petroleum ether and acetone extracts showed reduction effects on adult emergence. The repellent action of the plant extracts tested was varied depending on the solvent used in extraction and the dose of the extract. The most effective plant extract that evoked 100% repellency or biting deterrence was petroleum ether extract at a dose of 1.5 mg/cm2 compared with 100% repellency for commercial formulation, N,N-diethyl-3-methylbenzamide (DEET at the same dose. Hence, these extracts can be used as an effective alternative to the existing synthetic pesticides for the control of Ae. aegypti.

  15. Wolbachia infection reduces blood-feeding success in the dengue fever mosquito, Aedes aegypti.

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    Andrew P Turley

    Full Text Available BACKGROUND: The mosquito Aedes aegypti was recently transinfected with a life-shortening strain of the endosymbiont Wolbachia pipientis (wMelPop as the first step in developing a biocontrol strategy for dengue virus transmission. In addition to life-shortening, the wMelPop-infected mosquitoes also exhibit increased daytime activity and metabolic rates. Here we sought to quantify the blood-feeding behaviour of Wolbachia-infected females as an indicator of any virulence or energetic drain associated with Wolbachia infection. METHODOLOGY/PRINCIPAL FINDINGS: In a series of blood-feeding trials in response to humans, we have shown that Wolbachia-infected mosquitoes do not differ in their response time to humans, but that as they age they obtain fewer and smaller blood meals than Wolbachia-uninfected controls. Lastly, we observed a behavioural characteristic in the Wolbachia infected mosquitoes best described as a "bendy" proboscis that may explain the decreased biting success. CONCLUSIONS/SIGNIFICANCE: Taken together the evidence suggests that wMelPop infection may be causing tissue damage in a manner that intensifies with mosquito age and that leads to reduced blood-feeding success. These behavioural changes require further investigation with respect to a possible physiological mechanism and their role in vectorial capacity of the insect. The selective decrease of feeding success in older mosquitoes may act synergistically with other Wolbachia-associated traits including life-shortening and viral protection in biocontrol strategies.

  16. Substitution of Wild-Type Yellow Fever Asibi Sequences for 17D Vaccine Sequences in ChimeriVax–Dengue 4 Does Not Enhance Infection of Aedes aegypti Mosquitoes

    OpenAIRE

    Charles E McGee; Tsetsarkin, Konstantin; Vanlandingham, Dana L.; McElroy, Kate L.; Lang,Jean; Guy, Bruno; Decelle, Thierry; Higgs, Stephen

    2008-01-01

    To address concerns that a flavivirus vaccine/wild-type recombinant virus might have a high mosquito infectivity phenotype, the yellow fever virus (YFV) 17D backbone of the ChimeriVax– dengue 4 virus was replaced with the corresponding gene sequences of the virulent YFV Asibi strain. Field-collected and laboratory-colonized Aedes aegypti mosquitoes were fed on blood containing each of the viruses under investigation and held for 14 days after infection. Infection and dissemination rates were ...

  17. Bioefficacy of Mentha piperita essential oil against dengue fever mosquito Aedes aegypti L.

    Science.gov (United States)

    Kumar, Sarita; Wahab, Naim; Warikoo, Radhika

    2011-04-01

    To assess the larvicidal and repellent potential of the essential oil extracted from the leaves of peppermint plant, Mentha piperita (M. piperita) against the larval and adult stages of Aedes aegypti (Ae. Aegypti). The larvicidal potential of peppermint oil was evaluated against early fourth instar larvae of Ae. aegypti using WHO protocol. The mortality counts were made after 24 and 48 h, and LC50 and LC90 values were calculated. The efficacy of peppermint oil as mosquito repellent was assessed using the human-bait technique. The measured area of one arm of a human volunteer was applied with the oil and the other arm was applied with ethanol. The mosquito bites on both the arms were recorded for 3 min after every 15 min. The experiment continued for 3 h and the percent protection was calculated. The essential oil extracted from M. piperita possessed excellent larvicidal efficiency against dengue vector. The bioassays showed an LC50 and LC90 value of 111.9 and 295.18 ppm, respectively after 24 h of exposure. The toxicity of the oil increased 11.8% when the larvae were exposed to the oil for 48 h. The remarkable repellent properties of M. piperita essential oil were established against adults Ae. aegypti. The application of oil resulted in 100% protection till 150 min. After next 30 min, only 1-2 bites were recorded as compared with 8-9 bites on the control arm. The peppermint essential oil is proved to be efficient larvicide and repellent against dengue vector. Further studies are needed to identify the possible role of oil as adulticide, oviposition deterrent and ovicidal agent. The isolation of active ingredient from the oil could help in formulating strategies for mosquito control.

  18. Bioefficacy of Mentha piperita essential oil against dengue fever mosquito Aedes aegypti L

    Science.gov (United States)

    Kumar, Sarita; Wahab, Naim; Warikoo, Radhika

    2011-01-01

    Objective To assess the larvicidal and repellent potential of the essential oil extracted from the leaves of peppermint plant, Mentha piperita (M. piperita) against the larval and adult stages of Aedes aegypti (Ae. Aegypti). Methods The larvicidal potential of peppermint oil was evaluated against early fourth instar larvae of Ae. aegypti using WHO protocol. The mortality counts were made after 24 and 48 h, and LC50 and LC90 values were calculated. The efficacy of peppermint oil as mosquito repellent was assessed using the human-bait technique. The measured area of one arm of a human volunteer was applied with the oil and the other arm was applied with ethanol. The mosquito bites on both the arms were recorded for 3 min after every 15 min. The experiment continued for 3 h and the percent protection was calculated. Results The essential oil extracted from M. piperita possessed excellent larvicidal efficiency against dengue vector. The bioassays showed an LC50 and LC90 value of 111.9 and 295.18 ppm, respectively after 24 h of exposure. The toxicity of the oil increased 11.8% when the larvae were exposed to the oil for 48 h. The remarkable repellent properties of M. piperita essential oil were established against adults Ae. aegypti. The application of oil resulted in 100% protection till 150 min. After next 30 min, only 1-2 bites were recorded as compared with 8-9 bites on the control arm. Conclusions The peppermint essential oil is proved to be efficient larvicide and repellent against dengue vector. Further studies are needed to identify the possible role of oil as adulticide, oviposition deterrent and ovicidal agent. The isolation of active ingredient from the oil could help in formulating strategies for mosquito control. PMID:23569733

  19. Bioefficacy ofMentha piperita essential oil against dengue fever mosquito Aedes aegypti L

    Institute of Scientific and Technical Information of China (English)

    Sarita Kumar; Naim Wahab; Radhika Warikoo

    2011-01-01

    Objective:To assess the larvicidal and repellent potential of the essential oil extracted from the leaves of peppermint plant,Mentha piperita (M. piperita) against the larval and adult stages of Aedes aegypti (Ae. Aegypti).Methods: The larvicidal potential of peppermint oil was evaluated against early fourth instar larvae ofAe. aegypti usingWHO protocol. The mortality counts were made after 24 and48 h, and LC50 and LC90values were calculated. The efficacy of peppermint oil as mosquito repellent was assessed using the human-bait technique. The measured area of one arm of a human volunteer was applied with the oil and the other arm was applied with ethanol. The mosquito bites on both the arms were recorded for3 min after every15 min. The experiment continued for 3 h and the percent protection was calculated.Results:The essential oil extracted fromM. piperita possessed excellent larvicidal efficiency against dengue vector. The bioassays showed an LC50 and LC90 value of111.9 and295.18 ppm, respectively after24 h of exposure. The toxicity of the oil increased11.8% when the larvae were exposed to the oil for48 h. The remarkable repellent properties ofM. piperita essential oil were established against adults Ae. aegypti. The application of oil resulted in100% protection till150 min. After next30min, only1-2 bites were recorded as compared with8-9 bites on the control arm.Conclusions:The peppermint essential oil is proved to be efficient larvicide and repellent against dengue vector. Further studies are needed to identify the possible role of oil as adulticide, oviposition deterrent and ovicidal agent. The isolation of active ingredient from the oil could help in formulating strategies for mosquito control.

  20. Genetic structure and phylogeography of Aedes aegypti, the dengue and yellow-fever mosquito vector in Bolivia.

    Science.gov (United States)

    Paupy, Christophe; Le Goff, Gilbert; Brengues, Cécile; Guerra, Mabel; Revollo, Jimmy; Barja Simon, Zaïra; Hervé, Jean-Pierre; Fontenille, Didier

    2012-08-01

    Between the 16th and 18th centuries, Aedes aegypti (Diptera: Culicidae), a mosquito native to Africa, invaded the Americas, where it was successively responsible for the emergence of yellow fever (YF) and dengue (DEN). The species was eradicated from numerous American countries in the mid-20th century, but re-invaded them in the 1970s and 1980s. Little is known about the precise identities of Ae. aegypti populations which successively thrived in South America, or their relation with the epidemiological changes in patterns of YF and DEN. We examined these questions in Bolivia, where Ae. aegypti, eradicated in 1943, re-appeared in the 1980s. We assessed the genetic variability and population genetics of Ae. aegypti samples in order to deduce their genetic structure and likely geographic origin. Using a 21-population set covering Bolivia, we analyzed the polymorphism at nine microsatellite loci and in two mitochondrial DNA regions (COI and ND4). Microsatellite markers revealed a significant genetic structure among geographic populations (F(ST)=0.0627, PBolivia. Analysis of mtDNA sequences revealed the existence of two genetic lineages, one dominant lineage recovered throughout Bolivia, and the second restricted to rural localities in South Bolivia. Phylogenic analysis indicated that this minority lineage was related to West African Ae. aegypti specimens. In conclusion, our results suggested a temporal succession of Ae. aegypti populations in Bolivia, that potentially impacted the epidemiology of dengue and yellow fever. Copyright © 2012 Elsevier B.V. All rights reserved.

  1. Femoral compressive neuropathy from iliopsoas haematoma complicating dengue hemorrhagic fever

    Institute of Scientific and Technical Information of China (English)

    Sneha Ganu; Yesha Mehta

    2013-01-01

    Dengue fever is a debilitating mosquito-borne disease caused by dengue virus. We reported a case of femoral compression neuropathy due to iliopsoas hematoma complicating dengue hemorrhagic fever. Iliopsoas muscle hematoma can cause femoral neuropathy with resultant pain and paralysis. Such manifestations are not well documented in the literature. The pathogenesis of hematoma and compressive neuropathy with its appropriate management is discussed.

  2. Acute atrial fibrillation during dengue hemorrhagic fever

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    Veloso Henrique Horta

    2003-01-01

    Full Text Available Dengue fever is a viral infection transmitted by the mosquito, Aedes aegypti. Cardiac rhythm disorders, such as atrioventricular blocks and ventricular ectopic beats, appear during infection and are attributed to viral myocarditis. However, supraventricular arrhythmias have not been reported. We present a case of acute atrial fibrillation, with a rapid ventricular rate, successfully treated with intravenous amiodarone, in a 62-year-old man with dengue hemorrhagic fever, who had no structural heart disease.

  3. Dengue Fever/Dengue Haemorrhagic Fever : Case Management

    OpenAIRE

    Nimmannitya, Suchitra

    1995-01-01

    Dengue infections caused by the four antigenically distinct dengue virus serotypes (dengue virus 1, dengue virus 2, dengue virus 3, dengue virus 4) of the family Flavivindae, are the most important arbovirus disease in man, both in terms of morbidity and mortality. The infection is transmitted from man to man by Aedes mosquitoes. Since 1956, dengue virus infection has resulted in more than 3 million hospital admissions and more than 50,000 deaths in Southeast Asia, Western Pacific countries, ...

  4. The queenslandensis and the type Form of the Dengue Fever Mosquito (Aedes aegypti L. Are Genomically Indistinguishable.

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    Gordana Rašić

    2016-11-01

    Full Text Available The mosquito Aedes aegypti (L. is a major vector of viral diseases like dengue fever, Zika and chikungunya. Aedes aegypti exhibits high morphological and behavioral variation, some of which is thought to be of epidemiological significance. Globally distributed domestic Ae. aegypti have often been grouped into (i the very pale variety queenslandensis and (ii the type form. Because the two color forms co-occur across most of their range, there is interest in understanding how freely they interbreed. This knowledge is particularly important for control strategies that rely on mating compatibilities between the release and target mosquitoes, such as Wolbachia releases and SIT. To address this question, we analyzed nuclear and mitochondrial genome-wide variation in the co-occurring pale and type Ae. aegypti from northern Queensland (Australia and Singapore.We typed 74 individuals at a 1170 bp-long mitochondrial sequence and at 16,569 nuclear SNPs using a customized double-digest RAD sequencing. 11/29 genotyped individuals from Singapore and 11/45 from Queensland were identified as var. queenslandensis based on the diagnostic scaling patterns. We found 24 different mitochondrial haplotypes, seven of which were shared between the two forms. Multivariate genetic clustering based on nuclear SNPs corresponded to individuals' geographic location, not their color. Several family groups consisted of both forms and three queenslandensis individuals were Wolbachia infected, indicating previous breeding with the type form which has been used to introduce Wolbachia into Ae. aegypti populations.Aedes aegypti queenslandensis are genomically indistinguishable from the type form, which points to these forms freely interbreeding at least in Australia and Singapore. Based on our findings, it is unlikely that the presence of very pale Ae. aegypti will affect the success of Aedes control programs based on Wolbachia-infected, sterile or RIDL mosquitoes.

  5. The queenslandensis and the type Form of the Dengue Fever Mosquito (Aedes aegypti L.) Are Genomically Indistinguishable.

    Science.gov (United States)

    Rašić, Gordana; Filipović, Igor; Callahan, Ashley G; Stanford, Darren; Chan, Abigail; Lam-Phua, Sai Gek; Tan, Cheong Huat; Hoffmann, Ary Anthony

    2016-11-01

    The mosquito Aedes aegypti (L.) is a major vector of viral diseases like dengue fever, Zika and chikungunya. Aedes aegypti exhibits high morphological and behavioral variation, some of which is thought to be of epidemiological significance. Globally distributed domestic Ae. aegypti have often been grouped into (i) the very pale variety queenslandensis and (ii) the type form. Because the two color forms co-occur across most of their range, there is interest in understanding how freely they interbreed. This knowledge is particularly important for control strategies that rely on mating compatibilities between the release and target mosquitoes, such as Wolbachia releases and SIT. To address this question, we analyzed nuclear and mitochondrial genome-wide variation in the co-occurring pale and type Ae. aegypti from northern Queensland (Australia) and Singapore. We typed 74 individuals at a 1170 bp-long mitochondrial sequence and at 16,569 nuclear SNPs using a customized double-digest RAD sequencing. 11/29 genotyped individuals from Singapore and 11/45 from Queensland were identified as var. queenslandensis based on the diagnostic scaling patterns. We found 24 different mitochondrial haplotypes, seven of which were shared between the two forms. Multivariate genetic clustering based on nuclear SNPs corresponded to individuals' geographic location, not their color. Several family groups consisted of both forms and three queenslandensis individuals were Wolbachia infected, indicating previous breeding with the type form which has been used to introduce Wolbachia into Ae. aegypti populations. Aedes aegypti queenslandensis are genomically indistinguishable from the type form, which points to these forms freely interbreeding at least in Australia and Singapore. Based on our findings, it is unlikely that the presence of very pale Ae. aegypti will affect the success of Aedes control programs based on Wolbachia-infected, sterile or RIDL mosquitoes.

  6. DAY 1 DIAGNOSIS OF DENGUE FEVER

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    Shyam

    2014-09-01

    Full Text Available BACKGROUND: Dengue is an RNA virus of the family Flaviviridae transmitted by Aedes mosquitoes particularly Aedes aegypti. It is widely distributed throughout the tropics and subtropics and in a small proportion of cases the virus leads to life threatening complications dengue hemorrhagic fever and dengue shock syndrome. OBJECTIVES: To study the early diagnosis of Dengue on day 1 as there is no vaccine or specific antiviral treatment available. METHODS: A prospective study of 104 patients was done based on clinical criteria of Dengue. RESULTS: Out of 104 serum samples 46 (44% were positive by NSI Ag MICROELISA, 37 (35% by NSI antigen IMMUNO CHROMATOGRAPHY. 3 (2% samples are positive by IgM IMMUNO CHROMATOGRAPHY and only one sample was positive for IgG IMMUNOCHROMATOGRAPHY. CONCLUSION: The present study has established the significance of NSI Ag MICROELISA with NSI antigen IMMUNO CHROMATOGRAPHY in increasing the diagnostic efficiency in the day 1 diagnosis of Dengue fever.

  7. A model of dengue fever

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    Boutayeb A

    2003-02-01

    Full Text Available Abstract Background Dengue is a disease which is now endemic in more than 100 countries of Africa, America, Asia and the Western Pacific. It is transmitted to the man by mosquitoes (Aedes and exists in two forms: Dengue Fever and Dengue Haemorrhagic Fever. The disease can be contracted by one of the four different viruses. Moreover, immunity is acquired only to the serotype contracted and a contact with a second serotype becomes more dangerous. Methods The present paper deals with a succession of two epidemics caused by two different viruses. The dynamics of the disease is studied by a compartmental model involving ordinary differential equations for the human and the mosquito populations. Results Stability of the equilibrium points is given and a simulation is carried out with different values of the parameters. The epidemic dynamics is discussed and illustration is given by figures for different values of the parameters. Conclusion The proposed model allows for better understanding of the disease dynamics. Environment and vaccination strategies are discussed especially in the case of the succession of two epidemics with two different viruses.

  8. A Multipurpose, High-Throughput Single-Nucleotide Polymorphism Chip for the Dengue and Yellow Fever Mosquito, Aedes aegypti.

    Science.gov (United States)

    Evans, Benjamin R; Gloria-Soria, Andrea; Hou, Lin; McBride, Carolyn; Bonizzoni, Mariangela; Zhao, Hongyu; Powell, Jeffrey R

    2015-02-26

    The dengue and yellow fever mosquito, Aedes aegypti, contributes significantly to global disease burden. Genetic study of Aedes aegypti is essential to understanding its evolutionary history, competence as a disease vector, and the effects and efficacy of vector control methods. The prevalence of repeats and transposable elements in the Aedes aegypti genome complicates marker development and makes genome-wide genetic study challenging. To overcome these challenges, we developed a high-throughput genotyping chip, Axiom_aegypti1. This chip screens for 50,000 single-nucleotide polymorphisms present in Aedes aegypti populations from around the world. The array currently used genotypes 96 samples simultaneously. To ensure that these markers satisfy assumptions commonly made in many genetic analyses, we tested for Mendelian inheritance and linkage disequilibrium in laboratory crosses and a wild population, respectively. We have validated more than 25,000 of these markers to date, and expect this number to increase with more sampling. We also present evidence of the chip's efficacy in distinguishing populations throughout the world. The markers on this chip are ideal for applications ranging from population genetics to genome-wide association studies. This tool makes rapid, cost-effective, and comparable genotype data attainable to diverse sets of Aedes aegypti researchers, from those interested in potential range shifts due to climate change to those characterizing the genetic underpinnings of its competence to transmit disease.

  9. Human impacts have shaped historical and recent evolution in Aedes aegypti, the dengue and yellow fever mosquito

    Science.gov (United States)

    Brown, Julia E.; Evans, Benjamin R.; Zheng, Wei; Obas, Vanessa; Barrera-Martinez, Laura; Egizi, Andrea; Zhao, Hongyu; Caccone, Adalgisa; Powell, Jeffrey R.

    2013-01-01

    Though anthropogenic impacts are often considered harmful to species, human modifications to the landscape can actually create novel niches to which other species can adapt. These “domestication” processes are especially important in the context of arthropod disease vectors, where ecological overlap of vector and human populations may lead to epidemics. Here, we present results of a global genetic study of one such species, the dengue and yellow fever mosquito, Aedes aegypti, whose evolutionary history and current distribution have been profoundly shaped by humans. We used DNA sequences of four nuclear genes and 1504 SNP markers developed with RAD-tag sequencing to test the hypothesis that Ae. aegypti originated in Africa, where a domestic form arose and spread throughout the tropical and subtropical world with human trade and movement. Results confirmed African ancestry of the species, and supported a single subspeciation event leading to the pantropical domestic form. Additionally, genetic data strongly supported the hypothesis that human trade routes first moved domestic Ae. aegypti out of Africa into the New World, followed by a later invasion from the New World into Southeast Asia and the Pacific. These patterns of domestication and invasion are relevant to many species worldwide, as anthropogenic forces increasingly impact evolutionary processes. PMID:24111703

  10. Human impacts have shaped historical and recent evolution in Aedes aegypti, the dengue and yellow fever mosquito.

    Science.gov (United States)

    Brown, Julia E; Evans, Benjamin R; Zheng, Wei; Obas, Vanessa; Barrera-Martinez, Laura; Egizi, Andrea; Zhao, Hongyu; Caccone, Adalgisa; Powell, Jeffrey R

    2014-02-01

    Although anthropogenic impacts are often considered harmful to species, human modifications to the landscape can actually create novel niches to which other species can adapt. These "domestication" processes are especially important in the context of arthropod disease vectors, where ecological overlap of vector and human populations may lead to epidemics. Here, we present results of a global genetic study of one such species, the dengue and yellow fever mosquito, Aedes aegypti, whose evolutionary history and current distribution have been profoundly shaped by humans. We used DNA sequences of four nuclear genes and 1504 single nucleotide polymorphism (SNP) markers developed with restriction-site associated DNA (RAD) sequencing to test the hypothesis that Ae. aegypti originated in Africa, where a domestic form arose and spread throughout the tropical and subtropical world with human trade and movement. Results confirmed African ancestry of the species, and supported a single subspeciation event leading to the pantropical domestic form. In addition, genetic data strongly supported the hypothesis that human trade routes first moved domestic Ae. aegypti out of Africa into the New World, followed by a later invasion from the New World into Southeast Asia and the Pacific. These patterns of domestication and invasion are relevant to many species worldwide, as anthropogenic forces increasingly impact evolutionary processes. © 2013 The Author(s). Evolution © 2013 The Society for the Study of Evolution.

  11. Optimal Repellent Usage to Combat Dengue Fever.

    Science.gov (United States)

    Dorsett, Chasity; Oh, Hyunju; Paulemond, Marie Laura; Rychtář, Jan

    2016-05-01

    Dengue fever is one of the most important vector-borne diseases. It is transmitted by Aedes Stegomyia aegypti, and one of the most effective strategies to combat the disease is the reduction of exposure to bites of these mosquitoes. In this paper, we present a game-theoretical model in which individuals choose their own level of protection against mosquito bites in order to maximize their own benefits, effectively balancing the cost of protection and the risk of contracting the dengue fever. We find that even when the usage of protection is strictly voluntary, as soon as the cost of protection is about 10,000 times less than the cost of contracting dengue fever, the optimal level of protection will be within 5 % of the level needed for herd immunity.

  12. First Outbreak of Dengue Hemorrhagic Fever, Bangladesh

    OpenAIRE

    Rahman, Mahbubur; Rahman, Khalilur; Siddque, A. K.; Shoma, Shereen; A. H. M. Kamal; Ali, K.S.; Nisaluk, Ananda; Breiman, Robert F

    2002-01-01

    During the first countrywide outbreak of dengue hemorrhagic fever in Bangladesh, we conducted surveillance for dengue at a hospital in Dhaka. Of 176 patients, primarily adults, found positive for dengue, 60.2% had dengue fever, 39.2% dengue hemorrhagic fever, and 0.6% dengue shock syndrome. The Dengue virus 3 serotype was detected in eight patients.

  13. Severe Dengue Fever Outbreak in Taiwan

    Science.gov (United States)

    Wang, Sheng-Fan; Wang, Wen-Hung; Chang, Ko; Chen, Yen-Hsu; Tseng, Sung-Pin; Yen, Chia-Hung; Wu, Deng-Chyang; Chen, Yi-Ming Arthur

    2016-01-01

    Dengue fever (DF) is a vector-borne disease caused by dengue viruses (DENVs). Epidemic dengue occurs intermittently in Taiwan. In 2014, Taiwan experienced its largest DF outbreak. There were 15,732 DF cases reported. There were a total of 136 dengue hemorrhagic fever (DHF) cases, of which 20 resulted in death. Most DF cases were reported in southern Taiwan. A total of 15,043 (96%) cases were from Kaohsiung, a modern city in southern Taiwan. This report reviews DF epidemics in Taiwan during 2005–2014. The correlation between DF and DHF along with temperature and precipitation were conjointly examined. We conclude that most dengue epidemics in Taiwan resulted from imported DF cases. Results indicate three main factors that may have been associated with this DF outbreak in Kaohsiung: an underground pipeline explosion combined with subsequent rainfall and higher temperature. These factors may have enhanced mosquito breeding activity, facilitating DENV transmission. PMID:26572871

  14. Dengue fever with unusual thalamic involvement.

    Science.gov (United States)

    Mallick, Asim Kumar; Purkait, Radheshyam; Sinhamahapatra, Tapan Kumar

    2012-01-01

    Dengue is the most important mosquito-borne viral disease in the world and is caused by four distinct viruses (type 1 to 4) that are closely related antigenically. Infection by dengue virus may be asymptomatic or may lead to undifferentiated fever, dengue fever or dengue haemorrhagic fever. Recent observations indicate that the clinical profile of dengue is changing and the neurological complications are being reported more frequently. The neurological features includeheadache, seizures, neck stiffness, depressed sensorium, behavioural disorders, delirium, paralysis and cranial nerve palsies. Such neurological symptoms in dengue fever wereattributed to cerebral oedema, haemorrhage, haemoconcentration due to increasing vascular permeability, coagulopathy and release of toxic substances. Cerebral oedema, encephalitis-like changes (oedema and scattered focal lesions), intracranial haemorrhages as well as selective involvement of bilateral hippocampus in dengue infection have been reported previously on selective neuro-imaging but thalamic involvement is rare. We here report a case of a typical presentation of encephalopathy with left sided complete hemiplegia due to thalamic involvement in dengue infection.

  15. Treatment of dengue fever

    Directory of Open Access Journals (Sweden)

    Rajapakse S

    2012-07-01

    Full Text Available Senaka Rajapakse,1,2 Chaturaka Rodrigo,1 Anoja Rajapakse31Department of Clinical Medicine, Faculty of Medicine, University of Colombo, Sri Lanka; 2Lincoln County Hospital, United Lincolnshire NHS Trust, Lincoln, UK; 3Kings Mill Hospital, Sherwood Forest NHS Foundation Trust, Mansfield, UKAbstract: The endemic area for dengue fever extends over 60 countries, and approximately 2.5 billion people are at risk of infection. The incidence of dengue has multiplied many times over the last five decades at an alarming rate. In the endemic areas, waves of infection occur in epidemics, with thousands of individuals affected, creating a huge burden on the limited resources of a country's health care system. While the illness passes off as a simple febrile episode in many, a few have a severe illness marked by hypovolemic shock and bleeding. Iatrogenic fluid overload in the management may further complicate the picture. In this severe form dengue can be fatal. Tackling the burden of dengue is impeded by several issues, including a lack of understanding about the exact pathophysiology of the infection, inability to successfully control the vector population, lack of specific therapy against the virus, and the technical difficulties in developing a vaccine. This review provides an overview on the epidemiology, natural history, management strategies, and future directions for research on dengue, including the potential for development of a vaccine.Keywords: dengue, treatment, fluid resuscitation

  16. Dengue fever presenting as acute acalculus cholecystitis.

    Science.gov (United States)

    Joshipura, Vismit P; Soni, Harshad N; Patel, Nitin R; Haribhakti, Sanjiv P

    2007-06-01

    Classically dengue fever presents as fever with myalgia. A patient of dengue fever presented with classical symptoms and signs of acute acalculous cholecystitis. Serology and ultrasound examination identified dengue as the aetiology. Patient was treated successfully by conservative measures.

  17. Increase in larval gut proteolytic activities and Bti resistance in the Dengue fever mosquito.

    Science.gov (United States)

    Tetreau, Guillaume; Stalinski, Renaud; David, Jean-Philippe; Després, Laurence

    2013-02-01

    The bioinsecticide Bacillus thuringiensis var. israelensis (Bti) is increasingly used worldwide for mosquito control. Although no established resistance to Bti has been described in the field so far, a resistant Aedes aegypti strain (LiTOX strain) was selected in the laboratory using field-collected leaf litter containing Bti toxins. This selected strain exhibits a moderate resistance level to Bti, but a high resistance level to individual Cry toxins. As Bti contains four different toxins, generalist resistance mechanisms affecting mosquito tolerance to different toxins were expected in the resistant strain. In the present work, we show that the resistant strain exhibits an increase of various gut proteolytic activities including trypsins, leucine-aminopeptidases, and carboxypeptidase A activities. These elevated proteolytic activities resulted in a faster activation of Cry4Aa protoxins while Cry4Ba or Cry11Aa were not affected. These results suggest that changes in proteolytic activities may contribute to Bti resistance in mosquitoes together with other mechanisms. © 2012 Wiley Periodicals, Inc.

  18. Aedes mosquito salivary immune peptides:boost or block dengue viral infections

    Institute of Scientific and Technical Information of China (English)

    Natthanej Luplertlop

    2014-01-01

    Dengue virus, one of the most important arthropod-borne viruses, infected to human can severely cause dengue hemorrhagic fever and dengue shock syndrome. There are expected about 50 million dengue infections and 500 000 individuals are hospitalized with dengue hemorrhagic fever, mainly in Southeast Asia, Pacific, and in Americas reported each year. The rapid expansion of global dengue is one of a major public health challenge, together with not yet successful solutions of dengue epidemic control strategies. Thus, these dynamic dengue viral infections exhibited high demographic, societal, and public health infrastructure impacts on human. This review aimed to highlight the current understanding of dengue mosquito immune responses and role of mosquito salivary glands on dengue infection. These information may provide a valuable knowledge of disease pathogenesis, especially in mosquito vector and dengue virus interaction, which may help to control and prevent dengue distribution.

  19. Aedes mosquito salivary immune peptides: boost or block dengue viral infections

    Directory of Open Access Journals (Sweden)

    Natthanej Luplertlop

    2014-02-01

    Full Text Available Dengue virus, one of the most important arthropod-borne viruses, infected to human can severely cause dengue hemorrhagic fever and dengue shock syndrome. There are expected about 50 million dengue infections and 500 000 individuals are hospitalized with dengue hemorrhagic fever, mainly in Southeast Asia, Pacific, and in Americas reported each year. The rapid expansion of global dengue is one of a major public health challenge, together with not yet successful solutions of dengue epidemic control strategies. Thus, these dynamic dengue viral infections exhibited high demographic, societal, and public health infrastructure impacts on human. This review aimed to highlight the current understanding of dengue mosquito immune responses and role of mosquito salivary glands on dengue infection. These information may provide a valuable knowledge of disease pathogenesis, especially in mosquito vector and dengue virus interaction, which may help to control and prevent dengue distribution.

  20. Dengue fever presenting as acute liver failure- a case report

    Institute of Scientific and Technical Information of China (English)

    Rajat Jhamb; Bineeta Kashyap; Ranga GS; Kumar A

    2011-01-01

    Dengue fever(DF) and dengue haemorrhagic fever(DHF) are important mosquito-borne viral diseases of humans and recognized as important emerging infectious diseases in the tropics and subtropics. Compared to nine reporting countries in the 1950s, today the geographic distribution includes more than100 countries worldwide. Dengue viral infections are known to present a diverse clinical spectrum, ranging from asymptomatic illness to fatal dengue shock syndrome. Mild hepatic dysfunction in dengue haemorrhagic fever is usual. However, its presentation as acute liver failure(ALF)is unusual. We report a patient with dengue shock syndrome who presented with acute liver failure and hepatic encephalopathy in a recent outbreak of dengue fever in Delhi, India.

  1. Facing dengue fever - our first experience

    Directory of Open Access Journals (Sweden)

    Cvjetković Dejan

    2017-01-01

    Full Text Available Introduction. Dengue fever is a mosquito-borne disease caused by dengue virus, endemic in tropical and subtropical regions, where it is mostly imported from. The most common clinical form is classic dengue fever. We presented the first dengue case microbiologically confirmed in Serbia. Case report. A 34-year-old male got classic dengue fever after arrival from Cuba. The disease occurred suddenly with fever, myalgias, skin rash, hepatosplenomegaly, cytopenia, abnormal aminotransferase and creatine kinase levels. The diagnosis was confirmed with virological diagnostic methods. Significant leukopenia and thrombocytopenia as well as elevation of serum creatine kinase activity were recorded from the very beginning of hospitalization, but were gradually normalized. The whole duration of hospitalization was accompanied by laboratory signs of liver lesion. The disease had favourable outcome. At hospital discharge, the patient was afebrile, asymptomatic, with discrete erythematous rash on torso and arms, normal hemathological values and creatine kinase level and moderately elevated alanine-aminotransferase level. Conclusion. Considering global climate changes and growing international traffic, our health care service needs to be ready for possible massive outbreaks of dengue and other tropical infectious diseases in forthcoming years.

  2. Effective suppression of Dengue fever virus in mosquito cell cultures using retroviral transduction of hammerhead ribozymes targeting the viral genome.

    Science.gov (United States)

    Nawtaisong, Pruksa; Keith, James; Fraser, Tresa; Balaraman, Velmurugan; Kolokoltsov, Andrey; Davey, Robert A; Higgs, Stephen; Mohammed, Ahmed; Rongsriyam, Yupha; Komalamisra, Narumon; Fraser, Malcolm J

    2009-06-04

    Outbreaks of Dengue impose a heavy economic burden on developing countries in terms of vector control and human morbidity. Effective vaccines against all four serotypes of Dengue are in development, but population replacement with transgenic vectors unable to transmit the virus might ultimately prove to be an effective approach to disease suppression, or even eradication. A key element of the refractory transgenic vector approach is the development of transgenes that effectively prohibit viral transmission. In this report we test the effectiveness of several hammerhead ribozymes for suppressing DENV in lentivirus-transduced mosquito cells in an attempt to mimic the transgenic use of these effector molecules in mosquitoes. A lentivirus vector that expresses these ribozymes as a fusion RNA molecule using an Ae. aegypti tRNA(val) promoter and terminating with a 60A tail insures optimal expression, localization, and activity of the hammerhead ribozyme against the DENV genome. Among the 14 hammerhead ribozymes we designed to attack the DENV-2 NGC genome, several appear to be relatively effective in reducing virus production from transduced cells by as much as 2 logs. Among the sequences targeted are 10 that are conserved among all DENV serotype 2 strains. Our results confirm that hammerhead ribozymes can be effective in suppressing DENV in a transgenic approach, and provide an alternative or supplementary approach to proposed siRNA strategies for DENV suppression in transgenic mosquitoes.

  3. Effective suppression of Dengue fever virus in mosquito cell cultures using retroviral transduction of hammerhead ribozymes targeting the viral genome

    Directory of Open Access Journals (Sweden)

    Mohammed Ahmed

    2009-06-01

    Full Text Available Abstract Outbreaks of Dengue impose a heavy economic burden on developing countries in terms of vector control and human morbidity. Effective vaccines against all four serotypes of Dengue are in development, but population replacement with transgenic vectors unable to transmit the virus might ultimately prove to be an effective approach to disease suppression, or even eradication. A key element of the refractory transgenic vector approach is the development of transgenes that effectively prohibit viral transmission. In this report we test the effectiveness of several hammerhead ribozymes for suppressing DENV in lentivirus-transduced mosquito cells in an attempt to mimic the transgenic use of these effector molecules in mosquitoes. A lentivirus vector that expresses these ribozymes as a fusion RNA molecule using an Ae. aegypti tRNAval promoter and terminating with a 60A tail insures optimal expression, localization, and activity of the hammerhead ribozyme against the DENV genome. Among the 14 hammerhead ribozymes we designed to attack the DENV-2 NGC genome, several appear to be relatively effective in reducing virus production from transduced cells by as much as 2 logs. Among the sequences targeted are 10 that are conserved among all DENV serotype 2 strains. Our results confirm that hammerhead ribozymes can be effective in suppressing DENV in a transgenic approach, and provide an alternative or supplementary approach to proposed siRNA strategies for DENV suppression in transgenic mosquitoes.

  4. Surge of dengue virus infection and chikungunya Fever in bali in 2010: the burden of mosquito-borne infectious diseases in a tourist destination.

    Science.gov (United States)

    Yoshikawa, Minako Jen; Kusriastuti, Rita

    2013-06-01

    Labor flow and travelers are important factors contributing to the spread of Dengue virus infection and chikungunya fever. Bali Province of Indonesia, a popular resort and tourist destination, has these factors and suffers from mosquito-borne infectious diseases. Using area study approach, a series of fieldwork was conducted in Bali to obtain up-to-date primary disease data, to learn more about public health measures, and to interview health officers, hotel personnel, and other resource persons. The national data including information on two other provinces were obtained for comparison. The health ministry reported 5,810 and 11,697 cases of dengue hemorrhagic fever in Bali in 2009 and 2010, respectively. Moreover, two densely populated tourist areas and one district have shown a particularly high incidence and sharp increases in 2010. Cases of chikungunya fever reported in Bali more than doubled in 2010 from the previous year. Our findings suggest that Bali can benefit from a significant reduction in vector populations and dissemination of disease preventive knowledge among both local residents and foreign visitors. This will require a concerted and trans-border approach, which may prove difficult in the province.

  5. Substitution of wild-type yellow fever Asibi sequences for 17D vaccine sequences in ChimeriVax-dengue 4 does not enhance infection of Aedes aegypti mosquitoes.

    Science.gov (United States)

    McGee, Charles E; Tsetsarkin, Konstantin; Vanlandingham, Dana L; McElroy, Kate L; Lang, Jean; Guy, Bruno; Decelle, Thierry; Higgs, Stephen

    2008-03-01

    To address concerns that a flavivirus vaccine/wild-type recombinant virus might have a high mosquito infectivity phenotype, the yellow fever virus (YFV) 17D backbone of the ChimeriVax-dengue 4 virus was replaced with the corresponding gene sequences of the virulent YFV Asibi strain. Field-collected and laboratory-colonized Aedes aegypti mosquitoes were fed on blood containing each of the viruses under investigation and held for 14 days after infection. Infection and dissemination rates were based on antigen detection in titrated body or head triturates. Our data indicate that, even in the highly unlikely event of recombination or substantial backbone reversion, virulent sequences do not enhance the transmissibility of ChimeriVax viruses. In light of the low-level viremias that have been observed after vaccination in human volunteers coupled with low mosquito infectivity, it is predicted that the risk of mosquito infection and transmission of ChimeriVax vaccine recombinant/revertant viruses in nature is minimal.

  6. Dengue Fever: An Emerging Infectious Disease in The Bahamas

    Directory of Open Access Journals (Sweden)

    Bain, Sherrie Valarie

    2011-10-01

    Full Text Available Dengue fever is an emerging infectious disease that is increasing in prevalence in many geographic regions, including the Caribbean. It is the most common arboviral (vector-borne disease in the world, and infects more that 50 million people annually worldwide. The etiological agent of dengue fever is one of four serotypes of the Dengue virus (DENV1 – DENV4. The infection is transmitted via a human-mosquito-human route, when one or more species of the Aedes mosquito takes a blood meal from an infected host and then feeds on a person who is uninfected. There is no vaccine or cure for dengue fever. Dengue fever is a growing cause for concern in The Bahamas. This year the incidence of dengue fever reached epidemic proportions in The Bahamas. This article will explore the etiology and epidemiology of dengue fever, and offer some insight into how future the Bahamas can begin to develop strategies for the eradication of dengue fever.

  7. Dengue Hemorrhagic Fever: Epidemiology, Pathogenesis, and Its Transmission Risk Factors

    Directory of Open Access Journals (Sweden)

    Aryu Candra

    2010-12-01

    Full Text Available Dengue hemorrhagic fever is an infectious disease resulting spectrum of clinical manifestations that vary from the lightest, dengue fever, hemorrhagic fever and dengue fever are accompanied by shock or dengue shock syndrome. Its caused by dengue virus, transmitted by Aedes mosquitoes. The case is spread in the tropics, especially in Southeast Asia, Central America, America and the Caribbean, many causes of death in children 90% of them attacking children under 15 years old. Until now pathogenesis is unclear. There are two theories or hypotheses immuno-patogenesis DHF and DSS is still controversial which secondary infections (secondary heterologus infection and antibody-dependent enhancement. Risk factors for dengue transmission are rapid urban population growth, mobilization of the population because of improved transportation facilities and disrupted or weakened so that population control. Another risk factor is poverty which result in people not has the ability to provide a decent home and healthy, drinking water supply and proper waste disposal.

  8. Fundus Findings in Dengue Fever: A Case Report.

    Science.gov (United States)

    Şahan, Berna; Tatlıpınar, Sinan; Marangoz, Deniz; Çiftçi, Ferda

    2015-10-01

    Dengue fever is a flavivirus infection transmitted through infected mosquitoes, and is endemic in Southeast Asia, Central and South America, the Pacific, Africa and the Eastern Mediterranean region. A 41-year-old male patient had visual impairment after travelling to Thailand, which is one of the endemic areas. Cotton wool spots were observed on fundus examination. Fundus fluorescein angiography showed minimal vascular leakage from areas near the cotton wool spots and dot hemorrhages in the macula. Dengue fever should be considered in patients with visual complaints who traveled to endemic areas of dengue fever.

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

    Science.gov (United States)

    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

  10. Effect of high dose of steroid on plateletcount in acute stage of dengue Fever with thrombocytopenia.

    Science.gov (United States)

    Shashidhara, K C; Murthy, K A Sudharshan; Gowdappa, H Basavana; Bhograj, Abhijith

    2013-07-01

    Dengue infection is the most rapidly spreading mosquito-borne viral disease in the world and an estimated 50 million dengue infections reported annually. The pathogenesis of Thrombocytopenia in dengue fever (DF) is not clearly understood. Increased peripheral destruction of antibody coated platelets and acute bone marrow suppression were strongly suspected as the possible mechanism. This often leads to life threatening dengue hemorrhagic fever (DHF) and Dengue shock syndrome (DSS). Steroids are used in the treatment of Idiopathic thrombocytopenic purpura to increase the platelet count which is mediated by auto antibodies .This hypothesis would support the use of steroids in dengue fever. The objective of this study was to test whether an intravenous high dose dexamethasone was efficacious in increasing the platelet count in acute stage of dengue fever with thrombocytopenia. During the study period between June 2010 - 2011 in JSS Hospital Mysore, 127 patients were screened for dengue fever with thrombocytopenia (dengue fever.

  11. Preventing dengue and chikungunya fever among international travelers.

    Science.gov (United States)

    Tither, Pauline Herold

    2014-11-01

    To describe the vulnerability of U.S. travelers in tropical and subtropical regions of the world to dengue and chikungunya fever, to provide practical recommendations to avoid these mosquito-borne diseases, and to offer a communication tool as an aid for pretravel health consultations. Medical, epidemiological, and entomological research articles and reviews, and reports from government agencies. Dengue and chikungunya fever have growing public health impact around the world. International travelers return to the United States infected with these diseases. Mosquito bite avoidance is the only way to prevent dengue and chikungunya fever. Informed travelers have many options for simple and practical measures to lessen the risk of mosquito bites. A message map can be used as a communication tool for pretravel counseling on the prevention of dengue and chikungunya fever within the time frame of an office visit. In a pretravel health consultation, a nurse practitioner can promote travelers' health and prevent dengue, chikungunya fever, and other mosquito-borne diseases by counseling on the risk of these diseases and giving practical recommendations for prevention using a message map. ©2014 American Association of Nurse Practitioners.

  12. Modeled Forecasts of Dengue Fever in San Juan, PR Using NASA Satellite Enhanced Weather Forecasts

    Science.gov (United States)

    Morin, Cory; Quattrochi, Dale; Zavodsky, Bradley; Case, Jonathan

    2015-01-01

    Dengue virus is transmitted between humans and mosquitoes of the genus Aedes and causes approximately 96 million cases of disease (dengue fever) each year (Bhatet al. 2013). Symptoms of dengue fever include fever, headache, nausea, vomiting, and eye, muscle and joint pain (CDC). More sever manifestations such as abdominal pain, bleeding from nose and gums, vomiting of blood, and clammy skin occur in rare cases of dengue hemorrhagic fever (CDC). Dengue fever occurs throughout tropical and sub-tropical regions worldwide, however, the geographical range and size of epidemics is increasing. Weather and climate are drivers of dengue virus transmission dynamics (Morin et al. 2013) by affecting mosquito proliferation and the virus extrinsic incubation period (i.e. required time for the virus to replicate and disseminate within the mosquito before it can retransmit the virus).

  13. Dengue encephalitis-A rare manifestation of dengue fever

    OpenAIRE

    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...

  14. Dengue Fever-induced Thrombotic Microangiopathy: An Unusual Cause of Renal Failure.

    Science.gov (United States)

    Bhargava, V; Gupta, P; Kauntia, R; Bajpai, G

    2017-01-01

    Dengue fever is a tropical infection, which is mosquito-borne disease, caused by dengue virus and spread by Aedes mosquitoes. The incidence of dengue fever has risen rapidly over the past few years. About half of dengue infections are asymptomatic, and a great majority present with fever and body ache. However, the occurrence of complications is well known, including acute kidney injury (AKI). AKI in dengue is usually attributable to a pre-renal cause. Thrombotic microangiopathy is an extremely rare complication of dengue fever, with only a few published case reports in medical literature. This case intends to highlight the importance of recognizing dengue fever-induced thrombotic microangiopathy by physicians and pathologists, enabling better diagnosis and management of this life-threatening condition.

  15. Acute gingival bleeding as a complication of dengue hemorrhagic fever

    Directory of Open Access Journals (Sweden)

    Saif Khan

    2013-01-01

    Full Text Available Dengue fever is mosquito borne disease caused by dengue virus (DENV of Flaviviridae family. The clinical manifestations range from fever to severe hemorrhage, shock and death. Here, we report a case of 20-year-old male patient undergoing orthodontic treatment presenting with acute gingival bleeding with a history of fever, weakness, backache, retro orbital pain and ecchymosis over his right arm. The hematological investigations revealed anemia, thrombocytopenia and positive dengue non-structural protein-1 antigen and also positive immunoglobulin M and immunoglobulin G antibodies for DENV. Patient was diagnosed as a case of dengue hemorrhagic fever and was immediately referred for appropriate management. This case report emphasizes the importance of taking correct and thorough medical history.

  16. Dengue encephalitis-A rare manifestation of dengue fever

    Institute of Scientific and Technical Information of China (English)

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

    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.

  17. Dengue encephalitis–A rare manifestation of dengue fever

    Directory of Open Access Journals (Sweden)

    Deepak Madi

    2014-05-01

    Full Text Available 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.

  18. Is drought helping or killing dengue? Investigation of spatiotemporal relationship between dengue fever and drought

    Science.gov (United States)

    Lee, Chieh-Han; Yu, Hwa-Lung

    2015-04-01

    Dengue Fever is a vector-borne disease that is transmitted between human and mosquitos in tropical and sub-tropical regions. Previous studies have found significant relationship between the epidemic of dengue cases and climate variables, especially temperature and precipitation. Besides, the natural phenomena (e.g., drought) are considered that significantly drop the number of dengue cases by killing vector's breeding environment. However, in Kaohsiung City, Taiwan, there are evidences that the temporal pattern of dengue is correlated to drought events. Kaohsiung City experienced two main dengue outbreaks in 2002 and 2014 that both years were confirmed with serious drought. Especially in 2014, Kaohsiung City was suffered from extremely dengue outbreak in 2014 that reported the highest number of dengue cases in the history. This study constructs the spatiotemporal model of dengue incidences and index of drought events (Standardized Precipitation Index, SPI) based on the distributed lag nonlinear model (DLNM). Other meteorological measures are also included in the analysis.

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

    Science.gov (United States)

    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.

  20. Dengue virus and dengue fever%登革病毒和登革热

    Institute of Scientific and Technical Information of China (English)

    崔晓云; 吴艳花; 安静

    2014-01-01

    Dengue fever(DF) is the most widespread mosquito-borne diseases worldwide, caused by Dengue virus(DV). There are nearly half of the world's populations at the risk of infection in tropical and subtropical countries. DF is divided into Dengue and severe Dengue, which include Dengue hemorrhagic fever(DHF) and Dengue shock syndrome(DSS). With an estimated 500 000 cases of life-threatening disease in the form of severe Dengue every year, most of them are children. Notably, there is the most serious DF outbreak in southern China at 2014. This review will summarize several aspects of Dengue virus and Dengue fever to provide the information to the colleagues.%登革热(Dengue fever,DF)是由登革病毒(Dengue virus,DV)引起的一种虫媒传染病,主要在热带亚热带地区流行,全世界将近一半的人口有罹患 DF 的风险。 DF 在临床上分为 DF 和重症登革( severe Dengue),后者包括登革出血热( Dengue hemorrhagic fever,DHF)和登革休克综合征(Dengue shock syndrome,DSS)。每年重症登革病例达500000例,其中大多数患者为儿童。2014年 DF 在我国的南方地区出现历史上最严重的疫情,对人类健康和社会经济造成了严重损失。为此,本文对 DV 和DF 的概况作一综述,供广大同行参考。

  1. The Impacts of Mosquito Density and Meteorological Factors on Dengue Fever Epidemics in Guangzhou, China, 2006-2014:a Time-series Analysis

    Institute of Scientific and Technical Information of China (English)

    SHEN Ji Chuan; LUO Lei; LI Li; JING Qin Long; OU Chun Quan; YANG Zhi Cong; CHEN Xiao Guang

    2015-01-01

    Objective To explore the associations between the monthly number of dengue fever(DF) cases and possible risk factors in Guangzhou, a subtropical city of China. Methods The monthly number of DF cases, Breteau Index (BI), and meteorological measures during 2006-2014 recorded in Guangzhou, China, were assessed. A negative binomial regression model was used to evaluate the relationships between BI, meteorological factors, and the monthly number of DF cases. Results A total of 39,697 DF cases were detected in Guangzhou during the study period. DF incidence presented an obvious seasonal pattern, with most cases occurring from June to November. The current month’s BI, average temperature (Tave), previous month’s minimum temperature (Tmin), and Tave were positively associated with DF incidence. A threshold of 18.25 °C was found in the relationship between the current month’s Tmin and DF incidence. Conclusion Mosquito density, Tave, and Tmin play a critical role in DF transmission in Guangzhou. These findings could be useful in the development of a DF early warning system and assist in effective control and prevention strategies in the DF epidemic.

  2. The genetic architecture of a complex trait: Resistance to multiple toxins produced by Bacillus thuringiensis israelensis in the dengue and yellow fever vector, the mosquito Aedes aegypti.

    Science.gov (United States)

    Bonin, Aurélie; Paris, Margot; Frérot, Hélène; Bianco, Erica; Tetreau, Guillaume; Després, Laurence

    2015-10-01

    The bacterial insecticide Bacillus thuringiensis subsp. israelensis (Bti) is an increasingly popular alternative to chemical insecticides for controlling mosquito populations. Because Bti toxicity relies on the action of four main toxins, resistance to Bti is very likely a complex phenotype involving several genes simultaneously. Dissecting the underlying genetic basis thus requires associating a quantitative measure of resistance to genetic variation at many loci in a segregating population. Here, we undertake this task using the dengue and yellow fever vector, the mosquito Aedes aegypti, as a study model. We conducted QTL (Quantitative Trait Locus) and admixture mapping analyses on two controlled crosses and on an artificial admixed population, respectively, all obtained from resistant and susceptible lab strains. We detected 16 QTL regions, among which four QTLs were revealed by different analysis methods. These four robust QTLs explained altogether 29.2% and 62.2% of the total phenotypic variance in the two QTL crosses, respectively. They also all showed a dominant mode of action. In addition, we found six loci showing statistical association with Bti resistance in the admixed population. Five of the supercontigs highlighted in this study contained candidate genes as suggested by their function, or by prior evidence from expression and/or outlier analyses. These genomic regions are thus good starting points for fine mapping of resistance to Bti or functional analyses aiming at identifying the underlying genes and mutations. Moreover, for the purpose of this work, we built the first Ae. aegypti genetic map based on markers associated with genes expressed in larvae. This genetic map harbors 229 SNP markers mapped across the three chromosomes for a total length of 311.9cM. It brought to light several assembly discrepancies with the reference genome, suggesting a high level of genome plasticity in Ae. aegypti.

  3. Clinico-epidemiologicalfeatures of dengue fever in Saudi Arabia

    Institute of Scientific and Technical Information of China (English)

    Abdel-Hady El-Gilany; Abdelaziz Eldeib; Sabri Hammad

    2010-01-01

    Objective: To highlight some clinical and epidemiological features of dengue fever.Methods:All patients who were admitted to hospitals in Holly Mecca City, Saudi Arabia and were confirmed as dengue fever (DF) or dengue hemorrhagic fever (DHF) were included in this study. The data were collected from patient files and through direct interview with patients or their relatives. Cases were followed through their hospital stay. Routine laboratory investigations were done and diagnosis was confirmed by PCR.Results: Most of cases admitted in stable condition (94.37%) and only one case (1.41%) died. Dengue-1 and 3 types were the prevalent dengue viruses and cases in age group 16-44 were the most frequent (70.40%). The most common symptoms was fever reported from all cases followed by headache (74.60%), myalgia and anorexia (67.60%), back pain (59.20%) and chills (54.90%). DF represented (60.57%) of the cases while DHF represented (39.43%). About half of cases had underground water tanks for human use, 5.60% had over house roof water tanks and 43.70% had both types, 16.90% of these tanks were uncovered. Approximately 70.00% of cases reported presence of small collection of water nearby houses and 46.80% reported the presence of mosquitoes within their houses.Conclusions: Most dengue fever cases might be endogenous in origin due to prevalence of mosquitoes and their breeding places within the houses and in nearby localities. Control of mosquitoes and their breeding places will contribute to prevention of dengue fever.

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

  6. Cardiac Manifestation in Dengue Fever.

    Science.gov (United States)

    Arora, Mohit; Patil, Rekha S

    2016-07-01

    To study the cardiac manifestations of the dengue fever. This one year descriptive study was undertaken at KLES Dr. Prabhakar Kore Hospital and Medical Research Centre, Belgaum under the Department of Medicine. A total of 120 patients with either dengue IgM or IgM and IgG were studied. The assessment of cardiac manifestations was done based on electrocardiogram, 2D echocardiography and cardiac enzymes. Of the 120 patients, 85 (70.83%) were males and the male to female ratio was 2.4:1. The mean age of the patients was 33.02 ± 12.71 years. The commonest clinical presentation was myalgia (97.5%) followed by fever (92.5%). On clinical examination 33.33% of the patients had petecheia and only 9 patients having active bleeding manifestation at the time of presentation. A raised CK-MB and Troponin I was observed in 33.3% and 26.7% patients ECG findings revealed normal rhythm among 95% with 15.8% of them having an abnormal heart rate. Rhythm disturbance was noted in 5% of the patients with AV block being the most common (66.67%). Cardiac manifestation in the form of myocarditis was observed in 37.50% of the patients with a positive correlation with the severity of the dengue fever defined as by W.H.O. criteria. Patients with dengue fever are at high risk of developing myocarditis and rhythm disturbance and therefore require a close cardiac monitoring.

  7. Appendicular perforation in dengue fever: our experience

    Directory of Open Access Journals (Sweden)

    Gunjan Desai

    2014-09-01

    Full Text Available Dengue viral infections have become one of major emerging infectious diseases in the tropics. Acute abdomen occurring in dengue viral infection is not uncommon. The spectrums of acute surgical emergencies which raise suspicion of an abdominal catastrophe in patients presenting with dengue fever include acute pancreatitis, acute acalculous cholecystitis, non-specific peritonitis and very rarely acute appendicitis. The presence of low white cell count and platelet count can raise suspicion of a diagnosis of dengue in a patient presenting with acute abdominal pain, during a dengue epidemic. We herein report three patients with dengue fever who had appendicular perforation during the course of their viral fever.

  8. Dengue Fever Treatment

    Science.gov (United States)

    ... Some scientists are working to identify cellular and viral proteins to use as targets for drug intervention. In ... replication and transmission, and allow them eliminate the proteins in ... hundreds of viral strains that have been isolated from dengue-infected ...

  9. An unusual cause of acute abdominal pain in dengue fever.

    Science.gov (United States)

    Waseem, Tariq; Latif, Hina; Shabbir, Bilquis

    2014-07-01

    Dengue fever is an acute febrile viral disease caused by the bite of Aedes aegypti mosquito. It is a major health problem especially in tropical and subtropical areas including South East Asia and Pakistan. In the past few years, dengue fever has been endemic in Northern Punjab. Physicians managing dengue fever come across varied and uncommon complications of dengue fever. We report a case of dengue fever that developed severe right upper quadrant abdominal pain and induration after extreme retching and vomiting for 2 days. A rectus sheath hematoma was confirmed on noncontrast computed tomography (CT). Rectus sheath hematoma as a complication of dengue fever has rarely been reported before and never from this part of the world. Rectus sheath hematoma is an uncommon and often clinically misdiagnosed cause of abdominal pain. It is the result of bleeding into the rectus sheath from damage to the superior or inferior epigastric artery or their branches or from a direct tear of the rectus muscle. It can mimic almost any abdominal condition (See Fig.) (See Table).

  10. Yellow fever vaccination centers: concurrent vaccinations and updates on mosquito biology.

    Science.gov (United States)

    Arya, Subhash C; Agarwal, Nirmala

    2012-09-01

    Mandatory visits to immunization centers that offer pre-travel Yellow fever vaccine to prospective travelers would be useful for briefing the basics of the biology of the mosquito responsible for Yellow fever spread. Pre- travel knowledge on the day-time rather the nocturnal biting habit of the mosquitoes of Aedes species would prevent from bites of the mosquitoes responsible for the spread of viruses causing Yellow fever, dengue or Chikungunya infection.

  11. Dengue fever in patients with multiple sclerosis taking fingolimod or natalizumab.

    Science.gov (United States)

    Fragoso, Yara Dadalti; Gama, Paulo Diniz da; Gomes, Sidney; Khouri, Jussara Mathias Netto; Matta, André Palma da Cunha; Fernanda Mendes, Maria; Stella, Carla Renata Aparecida Vieira

    2016-03-01

    Dengue fever is the most prevalent mosquito-borne viral illness in humans. There may be different clinical manifestations of the disease, from mild symptoms to hemorrhagic forms of dengue fever and even neurological complications of this viral infection. Blood cells are usually affected, and thrombocytopenia is the hallmark of the disease. This paper presents 15 cases of dengue fever in patients with multiple sclerosis (MS) taking fingolimod or natalizumab. There were no complications of dengue fever or worse outcomes of MS in these patients, and only four of them needed short-term treatment withdrawal due to lymphopenia.

  12. Evaluation of repellent activities of Cymbopogon essential oils against mosquito vectors of Malaria, Filariasis and Dengue Fever in India.

    Science.gov (United States)

    Tyagi, B K; Shahi, A K; Kaul, B L

    1998-08-01

    Essential oils of four species and two hybrid varieties of Cymbopogon grasses were evaluated for their repellent properties against the major vector mosquitoes, namely, Anopheles stephensi, Culex quinque-fasciatus and Aedes aegypti, both in laboratory and field. The magnitude of repellency in the Cymbopogon essential oils was found to be of moderate to high order. All grass species protected completely from mosquito bites for 4 hrs, whereas C. nardus provided protection for as much as 8-10 hrs overnight.

  13. Analysis of significant factors for dengue fever incidence prediction.

    Science.gov (United States)

    Siriyasatien, Padet; Phumee, Atchara; Ongruk, Phatsavee; Jampachaisri, Katechan; Kesorn, Kraisak

    2016-04-16

    Many popular dengue forecasting techniques have been used by several researchers to extrapolate dengue incidence rates, including the K-H model, support vector machines (SVM), and artificial neural networks (ANN). The time series analysis methodology, particularly ARIMA and SARIMA, has been increasingly applied to the field of epidemiological research for dengue fever, dengue hemorrhagic fever, and other infectious diseases. The main drawback of these methods is that they do not consider other variables that are associated with the dependent variable. Additionally, new factors correlated to the disease are needed to enhance the prediction accuracy of the model when it is applied to areas of similar climates, where weather factors such as temperature, total rainfall, and humidity are not substantially different. Such drawbacks may consequently lower the predictive power for the outbreak. The predictive power of the forecasting model-assessed by Akaike's information criterion (AIC), Bayesian information criterion (BIC), and the mean absolute percentage error (MAPE)-is improved by including the new parameters for dengue outbreak prediction. This study's selected model outperforms all three other competing models with the lowest AIC, the lowest BIC, and a small MAPE value. The exclusive use of climate factors from similar locations decreases a model's prediction power. The multivariate Poisson regression, however, effectively forecasts even when climate variables are slightly different. Female mosquitoes and seasons were strongly correlated with dengue cases. Therefore, the dengue incidence trends provided by this model will assist the optimization of dengue prevention. The present work demonstrates the important roles of female mosquito infection rates from the previous season and climate factors (represented as seasons) in dengue outbreaks. Incorporating these two factors in the model significantly improves the predictive power of dengue hemorrhagic fever forecasting

  14. [Dengue fever--not just a tropical infectious disease].

    Science.gov (United States)

    Stock, Ingo

    2016-03-01

    Dengue fever is a viral disease that is transmitted primarily by Aedes mosquitoes, i. e., A. aegypti and A. albopictus. Other species are rarely involved. The disease is caused by dengue virus, an enveloped RNA virus which belongs to the family of flaviviridae. Although most infections are asymptomatic, in 20 to 30 percentages all cases infections are accompanied with high fever and other influenza-like signs of illness. Serious medical conditions with lethal complications also occur. During the last decades, the incidence of dengue fever rose sharply in many tropical and subtropical countries. In some of these regions, dengue is one of the leading causes of death in children. In Europe, since a few years a strong clustering of dengue fever cases has been registered in travelers returning from certain tropical or subtropical regions. Recently, autochthonous outbreaks have been observed on the Atlantic island of Madeira and in a few other regions of South Europe. Treatment of dengue fever is supportive and symptomatic, a specific therapy does not exist. For prevention of disease, vector control is of crucial importance.

  15. Scientists Create Mosquitoes Resistant to Dengue Virus

    Science.gov (United States)

    ... to the dengue virus, which might eventually help control the spread of the disease in humans. The team at Johns Hopkins Bloomberg School of Public Health in Baltimore genetically modified Aedes aegypti mosquitoes to boost their natural ability to fight ...

  16. Transfusion support in patients with dengue fever.

    Science.gov (United States)

    Kaur, Paramjit; Kaur, Gagandeep

    2014-09-01

    Dengue fever has emerged as a global public health problem in the recent decades. The clinical spectrum of the disease ranges from dengue fever to dengue hemorrhagic fever and dengue shock syndrome. The disease is characterized by increased capillary permeability, thrombocytopenia and coagulopathy. Thrombocytopenia with hemorrhagic manifestations warrants platelet transfusions. There is lack of evidence-based guidelines for transfusion support in patients with dengue fever. This contributes to inappropriate use of blood components and blood centers constantly face the challenge of inventory management during dengue outbreaks. The current review is aimed to highlight the role of platelets and other blood components in the management of dengue. The review was performed after searching relevant published literature in PubMed, Science Direct, Google scholar and various text books and journal articles.

  17. The Mosquitoes of Polynesia with a Pictorial Key to Some Species Associated with Filariasis and/or Dengue Fever

    Science.gov (United States)

    1977-01-01

    anterior surface c e e . . . . . . . . . . . . . . . . . roseni Belkin Urano taenia Propleuron with scales; vein R2 at most 0.6 length of vein Ml...annuZirostris Skuse The larva of samoaensis (Theobald) is unknown. Mosquito Systematics Vol. 9(3) 1977 Urano taenia Seta 9-M, T single . . o e

  18. [Coexistence of acute appendicitis and dengue fever: A case report].

    Science.gov (United States)

    Osuna-Ramos, Juan Fidel; Silva-Gracia, Carlos; Maya-Vacio, Gerardo Joel; Romero-Utrilla, Alejandra; Ríos-Burgueño, Efrén Rafael; Velarde-Félix, Jesús Salvador

    2017-01-03

    Dengue is the most important human viral disease transmitted by mosquitoes. It can be asymptomatic or it can present in any of its 3clinical forms: Dengue fever, dengue haemorrhagic fever and dengue shock syndrome. However, some atypical manifestations have been reported in surgical emergencies caused by acute appendicitis in patients with dengue fever. We report the case of an 18-year-old Mexican male who presented to the emergency department of the General Hospital of Culiacan, Sinaloa, with symptoms of dengue fever, accompanied by crampy abdominal pain with positive Rovsing and Dunphy signs. Dengue infection was confirmed by a positive NS1 antigen test performed by enzyme-linked immunosorbent assay. An abdominal ultrasound revealed an appendicular process; as the abdominal pain in the right side kept increasing, an open appendectomy was performed. Abundant inflammatory liquid was observed during the surgery, and the pathology laboratory reported an oedematous appendix with fibrinopurulent plaques, which agreed with acute ulcerative appendicitis. The patient was discharged fully recovered without complications during the follow-up period. Acute abdominal pain can be caused in some cases by dengue infection. This can be confusing, which can lead to unnecessary surgical interventions, creating additional morbidities and costs for the patient. This unusual and coincident acute appendicitis with dengue highlights the importance of performing careful clinical studies for appropriate decision making, especially in dengue endemic regions during an outbreak of this disease. Copyright © 2016 Academia Mexicana de Cirugía A.C. Publicado por Masson Doyma México S.A. All rights reserved.

  19. Differential proteomic analysis of virus-enriched fractions obtained from plasma pools of patients with dengue fever or severe dengue.

    Science.gov (United States)

    Fragnoud, Romain; Flamand, Marie; Reynier, Frederic; Buchy, Philippe; Duong, Vasna; Pachot, Alexandre; Paranhos-Baccala, Glaucia; Bedin, Frederic

    2015-11-14

    Dengue is the most widespread mosquito-borne viral disease of public health concern. In some patients, endothelial cell and platelet dysfunction lead to life-threatening hemorrhagic dengue fever or dengue shock syndrome. Prognostication of disease severity is urgently required to improve patient management. The pathogenesis of severe dengue has not been fully elucidated, and the role of host proteins associated with viral particles has received little exploration. The proteomes of virion-enriched fractions purified from plasma pools of patients with dengue fever or severe dengue were compared. Virions were purified by ultracentrifugation combined with a water-insoluble polyelectrolyte-based technique. Following in-gel hydrolysis, peptides were analyzed by nano-liquid chromatography coupled to ion trap mass spectrometry and identified using data libraries. Both dengue fever and severe dengue viral-enriched fractions contained identifiable viral envelope proteins and host cellular proteins. Canonical pathway analysis revealed the identified host proteins are mainly involved in the coagulation cascade, complement pathway or acute phase response signaling pathway. Some host proteins were over- or under-represented in plasma from patients with severe dengue compared to patients with dengue fever. ELISAs were used to validate differential expression of a selection of identified host proteins in individual plasma samples of patients with dengue fever compared to patients with severe dengue. Among 22 host proteins tested, two could differentiate between dengue fever and severe dengue in two independent cohorts (olfactomedin-4: area under the curve (AUC), 0.958; and platelet factor-4: AUC, 0.836). A novel technique of virion-enrichment from plasma has allowed to identify two host proteins that have prognostic value for classifying patients with acute dengue who are more likely to develop a severe dengue. The impact of these host proteins on pathogenicity and disease outcome

  20. A case of imported dengue fever from Burkina Faso to Japan in October 2016.

    Science.gov (United States)

    Hashimoto, Takehiro; Kutsuna, Satoshi; Maeki, Takahiro; Tajima, Shigeru; Takaya, Saho; Katanami, Yuichi; Yamamoto, Kei; Takeshita, Nozomi; Hayakawa, Kayoko; Kato, Yasuyuki; Kanagawa, Shuzo; Ohmagari, Norio

    2017-09-11

    Dengue fever remains underreported in Africa due to lack of awareness among healthcare providers, the presence of other febrile illnesses, and insufficient laboratory testing. We present a case of imported dengue fever from Burkina Faso to Japan, where an outbreak of dengue was reported on October 18, 2016. The phylogenetic analysis revealed that the isolate from our patient belonged to a distinct of sylvatic dengue viruses, suggesting that dengue viruses have been maintained in the mosquitoes and human cycles in Burkina Faso for more than 30 years.

  1. ELISA as an alternative tool for epidemiological surveillance for dengue in mosquitoes: a report from Thailand

    Directory of Open Access Journals (Sweden)

    Mayuna Srisuphanunt, Ratana Sithiprasasna, Somboon Patpoparn, Watcharee Attatippaholkun & Viroj Wiwanitkit

    2007-12-01

    Full Text Available Background & objectives: Dengue fever (DF, dengue hemorrhagic fever (DHF and dengue shocksyndrome (DSS are the re-emerging infectious diseases caused by the four serotypes of dengue(DEN virus, type 1 to 4, belonging to the family Flaviviridae and genus Flavivirus. In the absenceof a safe and effective mass immunisation, the prevention and control of dengue outbreaks dependupon the surveillance of cases and mosquito vector. The aim of this work is to test enzyme-linkedimmunosorbent assay (ELISA tool for the virological surveillance of dengue.Methods: Virus-infected Aedes mosquitoes were collected from the field in order to serve as anearly warning monitoring tool for dengue outbreaks. In a prospective field study conducted fromApril to September 2000, female adult Aedes mosquitoes were caught from selected dengue-sensitivearea in Chombung district, Ratchaburi province and assayed by ELISA.Result: Approximately 18.3% were found positive for dengue virus.Conclusion: This can imply that ELISA can be an alternative tool for epidemiological surveillancefor dengue in mosquitoes.

  2. The Knowledge and Experience of Dengue Mosquitoes among Housewives.

    Directory of Open Access Journals (Sweden)

    Atik Triratnawati

    2011-06-01

    Full Text Available Dengue Hemorrhagic Fever (DHF prevention programs in Semarang, were focused through controlling mosquito breeding sites (PSN, but the implementation of PSN was not become a habit in every household. The objective of this study was to explore knowledge and experience of dengue mosquitoes among housewives in the endemic villages.The research was using qualitative methods. Subjects of the study were 17 housewives which selected by purposive sampling. The data collection was carried in Sendangmulyo village, Semarang, through observation, focus groups discussions, and indepth interviews. The techniques used to test data validity were triangulation and member checking method. Data were analyzed using content analysis approached. The results showed that housewives classifying mosquito based on time occurrence whether the presence of mosquito in environment was perceived naturally. Unoptimalized PSN behavior was based on the lack of housewives knowledge on larvae development stages. Mosquito was not considered as a threatening because night mosquito biting was directly more disturbing rather than day mosquitoes’. Health promotion program could increase dasa wisma cadres knowledge and skill, particularly on mosquito life cycle and the correct stages of PSN behavior. This study did not distinguish the demographic characteristics of informants. Further reserch could explore it or develop media based on local knowledge and experience.

  3. Don't Let the Bugs Bite: Preventing Dengue and Other Diseases Spread by Mosquitoes

    Centers for Disease Control (CDC) Podcasts

    2007-12-10

    This year (2007) CDC is receiving a great many reports of cases of Dengue fever, which is spread by mosquitoes. This podcast discusses ways travelers to the tropics can protect themselves from mosquito bites.  Created: 12/10/2007 by National Center for the Prevention, Detection and Control of Infectious Diseases (NCPDCID).   Date Released: 12/10/2007.

  4. Dengue hemorrhagic fever complicated by pancreatitis

    Directory of Open Access Journals (Sweden)

    Guido Ricardo Gonzalez Fontal

    2011-10-01

    Full Text Available Acute pancreatitis is an atypical complication of dengue fever and is rarely described. We are reporting a case of dengue hemorrhagic fever complicated by acute pancreatitis in a patient with history of diabetes mellitus type 1 and end stage renal disease on hemodialysis.

  5. The Impact of Transgenic Mosquitoes on Dengue Virulence to Humans and Mosquitoes

    OpenAIRE

    Medlock, Jan; Luz, Paula M; Struchiner,Claudio J.; Galvani, Alison P.

    2009-01-01

    Dengue is a major public health concern in the tropics and subtropics. Innovative transgenic strategies to render Aedes aegypti mosquitoes, the primary vector of dengue, incompetent for dengue transmission are under development. We modeled the evolutionary impact of different transgenic mosquito strategies on dengue-induced mortality, that is, dengue virulence, to both humans and mosquitoes. This model incorporates various evolutionary trade-offs in dengue virus epidemiological traits, for ex...

  6. Help Control Mosquitoes that Spread Dengue, Chikungunya, and Zika Viruses

    Science.gov (United States)

    Help Control Mosquitoes that Spread Dengue, Chikungunya, and Zika Viruses B Z Z Z Z . Aside from ... or Aedes albopictus ) can spread dengue, chikungunya, or Zika viruses. People become infected with dengue, chikungunya, or ...

  7. Genomic organization and splicing evolution of the doublesex gene, a Drosophila regulator of sexual differentiation, in the dengue and yellow fever mosquito Aedes aegypti

    Science.gov (United States)

    2011-01-01

    Background In the model system Drosophila melanogaster, doublesex (dsx) is the double-switch gene at the bottom of the somatic sex determination cascade that determines the differentiation of sexually dimorphic traits. Homologues of dsx are functionally conserved in various dipteran species, including the malaria vector Anopheles gambiae. They show a striking conservation of sex-specific regulation, based on alternative splicing, and of the encoded sex-specific proteins, which are transcriptional regulators of downstream terminal genes that influence sexual differentiation of cells, tissues and organs. Results In this work, we report on the molecular characterization of the dsx homologue in the dengue and yellow fever vector Aedes aegypti (Aeadsx). Aeadsx produces sex-specific transcripts by alternative splicing, which encode isoforms with a high degree of identity to Anopheles gambiae and Drosophila melanogaster homologues. Interestingly, Aeadsx produces an additional novel female-specific splicing variant. Genomic comparative analyses between the Aedes and Anopheles dsx genes revealed a partial conservation of the exon organization and extensive divergence in the intron lengths. An expression analysis showed that Aeadsx transcripts were present from early stages of development and that sex-specific regulation starts at least from late larval stages. The analysis of the female-specific untranslated region (UTR) led to the identification of putative regulatory cis-elements potentially involved in the sex-specific splicing regulation. The Aedes dsx sex-specific splicing regulation seems to be more complex with the respect of other dipteran species, suggesting slightly novel evolutionary trajectories for its regulation and hence for the recruitment of upstream splicing regulators. Conclusions This study led to uncover the molecular evolution of Aedes aegypti dsx splicing regulation with the respect of the more closely related Culicidae Anopheles gambiae orthologue

  8. Genomic organization and splicing evolution of the doublesex gene, a Drosophila regulator of sexual differentiation, in the dengue and yellow fever mosquito Aedes aegypti

    Directory of Open Access Journals (Sweden)

    Arcà Bruno

    2011-02-01

    Full Text Available Abstract Background In the model system Drosophila melanogaster, doublesex (dsx is the double-switch gene at the bottom of the somatic sex determination cascade that determines the differentiation of sexually dimorphic traits. Homologues of dsx are functionally conserved in various dipteran species, including the malaria vector Anopheles gambiae. They show a striking conservation of sex-specific regulation, based on alternative splicing, and of the encoded sex-specific proteins, which are transcriptional regulators of downstream terminal genes that influence sexual differentiation of cells, tissues and organs. Results In this work, we report on the molecular characterization of the dsx homologue in the dengue and yellow fever vector Aedes aegypti (Aeadsx. Aeadsx produces sex-specific transcripts by alternative splicing, which encode isoforms with a high degree of identity to Anopheles gambiae and Drosophila melanogaster homologues. Interestingly, Aeadsx produces an additional novel female-specific splicing variant. Genomic comparative analyses between the Aedes and Anopheles dsx genes revealed a partial conservation of the exon organization and extensive divergence in the intron lengths. An expression analysis showed that Aeadsx transcripts were present from early stages of development and that sex-specific regulation starts at least from late larval stages. The analysis of the female-specific untranslated region (UTR led to the identification of putative regulatory cis-elements potentially involved in the sex-specific splicing regulation. The Aedes dsx sex-specific splicing regulation seems to be more complex with the respect of other dipteran species, suggesting slightly novel evolutionary trajectories for its regulation and hence for the recruitment of upstream splicing regulators. Conclusions This study led to uncover the molecular evolution of Aedes aegypti dsx splicing regulation with the respect of the more closely related Culicidae

  9. Unusual Presentation of Dengue Fever

    Science.gov (United States)

    Aslam, Moaz; Aleem, Numra A.; Zahid, Mohammad F.; Rahman, Arshalooz J.

    2016-01-01

    Dengue fever (DF) is an acute febrile illness that follows a self-limiting course. However, some patients suffer from complications, including myocarditis, due to the involvement of other organs. A child presented at the Aga Khan University Hospital in Karachi, Pakistan, in June 2013 with a high-grade fever, malaise and epigastric pain radiating to the chest. Positive DF antigen and immunoglobulin M assays confirmed the diagnosis of DF. Persistent bradycardia with low blood pressure led to further cardiac investigations which showed a decreased ejection fraction and raised serum cardiac enzymes, indicating myocardial damage. With supportive care and use of inotropes, the spontaneous normalisation of cardiac enzyme levels and ejection fraction was observed. The child was discharged five days after admission. This case highlights the importance of identifying myocarditis in DF patients suffering from cardiac symptoms that are not explained by other potential aetiologies. Awareness, early suspicion and supportive care are essential to ensure favourable outcomes. PMID:26909198

  10. Hemophagocytic syndrome in classic dengue fever

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    Sayantan Ray

    2011-01-01

    Full Text Available A 24-year-old previously healthy girl presented with persistent fever, headache, and jaundice. Rapid-test anti-dengue virus IgM antibody was positive but anti-dengue IgG was nonreactive, which is suggestive of primary dengue infection. There was clinical deterioration during empiric antibiotic and symptomatic therapy. Bone marrow examination demonstrated the presence of hemophagocytosis. Diagnosis of dengue fever with virus-associated hemophagocytic syndrome was made according to the diagnostic criteria of the HLH 2004 protocol of the Histiocyte Society. The patient recovered with corticosteroid therapy. A review of literature revealed only a handful of case reports that showed the evidence that this syndrome is caused by dengue virus. Our patient is an interesting case of hemophagocytic syndrome associated with classic dengue fever and contributes an additional case to the existing literature on this topic. This case highlights the need for increased awareness even in infections not typically associated with hemophagocytic syndrome.

  11. Hemophagocytic syndrome in classic dengue Fever.

    Science.gov (United States)

    Ray, Sayantan; Kundu, Supratip; Saha, Manjari; Chakrabarti, Prantar

    2011-10-01

    A 24-year-old previously healthy girl presented with persistent fever, headache, and jaundice. Rapid-test anti-dengue virus IgM antibody was positive but anti-dengue IgG was nonreactive, which is suggestive of primary dengue infection. There was clinical deterioration during empiric antibiotic and symptomatic therapy. Bone marrow examination demonstrated the presence of hemophagocytosis. Diagnosis of dengue fever with virus-associated hemophagocytic syndrome was made according to the diagnostic criteria of the HLH 2004 protocol of the Histiocyte Society. The patient recovered with corticosteroid therapy. A review of literature revealed only a handful of case reports that showed the evidence that this syndrome is caused by dengue virus. Our patient is an interesting case of hemophagocytic syndrome associated with classic dengue fever and contributes an additional case to the existing literature on this topic. This case highlights the need for increased awareness even in infections not typically associated with hemophagocytic syndrome.

  12. A review of dengue fever: a resurging tropical disease.

    Science.gov (United States)

    Mangold, Karen A; Reynolds, Sally L

    2013-05-01

    Dengue is a resurging mosquito-borne disease that is often contracted in U.S. travelers to Latin America, Asia, and the Caribbean. The clinical symptoms range from a simple febrile illness to hemorrhagic fever or shock. The clinical course has a wide range of outcomes, and adequate supportive care can reduce mortality rates dramatically. Repeated exposures to the virus can lead to a more complicated clinical course.

  13. Emergence of traveling waves in the spreading of dengue fever

    Science.gov (United States)

    Bianco, Simone; Faatz, Andrea; Cummings, Derek; Shaw, Leah

    2010-03-01

    Dengue fever is a multistrain mosquito-borne subtropical disease that exhibits complex oscillatory outbreaks. Epidemiological data from Thailand displays traveling waves of infection originating in Bangkok, the largest population center (Cummings et al., Nature 427: 344, 2004). We present a multistrain metapopulation model in which traveling wave like behavior results from migration coupling between heterogeneous regions. The region with the highest effective person-to-person contact rate leads the dynamics. A stochastic version of the model will also be presented.

  14. Investigation of spatiotemporal relationship between dengue fever and drought

    Science.gov (United States)

    Lee, Chieh-Han; Yu, Hwa-Lung

    2016-04-01

    Dengue Fever is a vector-borne disease that is transmitted between human and mosquitos in tropical and sub-tropical regions. Previous studies have found significant relationship between the epidemic of dengue cases and climate variables, especially temperature and precipitation. Besides, the natural phenomena (e.g., drought) are considered that significantly drop the number of dengue cases by killing vector's breeding environment. However, in Kaohsiung City, Taiwan, there are evidences that the temporal pattern of dengue is correlated to drought events. Kaohsiung City experienced two main dengue outbreaks in 2002 and 2014 that both years were confirmed with serious drought. Especially in 2014, Kaohsiung City was suffered from extremely dengue outbreak in 2014 that reported the highest number of dengue cases in the history. Otherwise, another nearby city, Tainan City, had reported the biggest outbreak in 2015. This study constructs the spatiotemporal model of dengue incidences and index of drought events (Standardized Precipitation Index, SPI) based on the distributed lag nonlinear model (DLNM). Other meteorological measures are also included in the analysis.

  15. Anterior ischemic optic neuropathy following dengue fever.

    Science.gov (United States)

    Ramakrishnan, Reshma; Shrivastava, Saurabh; Deshpande, Shrikant; Patkar, Priyanka

    2016-01-01

    Dengue fever is caused by a flavivirus. This infection is endemic in the tropics and warm temperate regions of the world. Ocular manifestations of dengue fever include subconjunctival, vitreous, and retinal haemorrhages; posterior uveitis; optic neuritis; and maculopathies, haemorrhage, and oedema. However anterior ischemic optic neuropathy is a rare presentation. Optic nerve ischemia most frequently occurs at the optic nerve head, where structural crowding of nerve fibers and reduction of the vascular supply may combine to impair perfusion to a critical degree and produce optic disc oedema. Here we present a case of anterior ischemic optic neurapathy associated with dengue fever.

  16. Hepatic involvement in dengue Fever in children.

    Science.gov (United States)

    Jagadishkumar, Kalenahalli; Jain, Puja; Manjunath, Vaddambal G; Umesh, Lingappa

    2012-06-01

    Hepatic dysfunction is common in dengue infection and the degree of liver dysfunction in children varies from mild injury with elevation of transaminases to severe injury with jaundice. This study was undertaken to assess the spectrum of hepatic involvement in dengue infection. 110 children with serologically positive dengue fever aged between 2 months - 14 years were studied for their hepatic functions both clinically and biochemically after excluding malaria, enteric fever, Hepatitis A and Hepatitis B with relevant investigations. All cases were grouped into DF (Dengue fever), DHF (Dengue hemorrhagic fever) and DSS (Dengue shock syndrome) according to WHO criteria. The spectrum of hepatic manifestations included hepatomegaly (79%), hepatic tenderness (56%), jaundice (4.5%), raised levels of aspartate transaminase (AST)(93%), alanine transaminase (ALT)(78%), alkaline phosphatase (AP) (57%), prolonged prothrombin time (PT) (20%), reduced levels of serum albumin (66%) and abnormal abdomen ultrasound (65%). Hepatic dysfunction was observed more in DHF and DSS group compared to DF group. About 17.27% of children had >10 fold increase in the liver enzymes. There was no correlation between the degree of hepatic enlargement or hepatic tenderness with the abnormalities of liver functions. Any child with fever, jaundice and tender hepatomegaly in geographical areas where dengue is endemic, the diagnosis of dengue infection should be strongly considered.

  17. 2005~2010年防城港市登革热蚊媒监测结果分析%Results of surveillance of mosquito vectors transmittingh dengue fever in Fangchenggang City from 2005 to 2010

    Institute of Scientific and Technical Information of China (English)

    黄定芳; 凌宝珍; 黄衍晶; 班有鹤; 李锋华; 李忠伦

    2011-01-01

    目的 分析2005~2010年防城港市登革热监测结果,为登革热流行趋势的预测、预警和制定防治对策提供科学依据.方法 收集本市2005~2010年2个监测点媒介伊蚊的监测资料,进行描述性统计分析.结果 防城港市的优势蚊种为白纹伊蚊,未发现埃及伊蚊;监测点大部分监测月份伊蚊布雷图指数(BI)均超过5的安全水平,其中水田屯蚊媒密度较高,最高BI达104,企沙街相对较低,最高BI为54,2009年以后企沙街蚊媒密度明显降低;阳性容器以暂时性容器为主;2006年送检的全部成蚊标本未检测到登革热病毒核酸或分离到病毒.结论 防城港市在虫媒方面已经具备传播登革热病毒的条件,存在登革热流行的潜在危险,应加强监测、卫生宣教以及改善农村环境.%Objective To analyze the results in monitoring of mosquito vectors transmitting dengue fever in Fangchenggang city from 2005 to 2010 and provide scientific basis for forecasting the prevalent trend,early warning and making control measures. Methods The data of surveillance of Aedes mosquito vectors in tow monitoring sites from 2005-2010 were collected and descriptively analyzed. Results The predominated mosquito vectors in Fangchenggang City was Aedes albopictus and Aedes aegypti was not found. The Breteau Index (BI) in each month was under 5. The BI in paddy field was 104,the highest and that in the Qishajie was at a relatively low level of 54 and further reduced since 2009. Most of the positive containers were temporary one. No dengue virus and dengue dengue virus nucleic acid were isolated or detected from the samples collected since 2006. Conclusion The mosquito vectors transmitting dengue fever was capable of transmission of the disease and there was the potential of prevalence of dengue fever in Fangchenggang City. Thus the practice of surveillance, health propaganda and modification of environment be strengthened.

  18. Oral manifestations of dengue fever: A rarity and literature review

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    Vinay Kumar Bhardwaj

    2016-01-01

    Full Text Available Dengue is a viral infection with fatal potential complications. It is also called break-bone fever. Worldwide, dengue infection is the most common mosquito-borne viral disease. It is caused by vector Aedes aegypti and represents a major public health issue in more than 100 tropical countries. This may be associated with a variety of mucocutaneous manifestations, which may be of help in early diagnosis. 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 infections. Many biochemical assays and hematological investigations may aid in the further diagnosis and treatment of the fatal disease. Although oral lesions are uncommon in dengue infections and if occur, may be mistaken for platelet abnormality or hemorrhagic disorders. This review emphasizes the significance of oral lesions as it may be the early indicators of dengue hemorrhagic fever.

  19. Dengue fever treatment with Carica papaya leaves extracts.

    Science.gov (United States)

    Ahmad, Nisar; Fazal, Hina; Ayaz, Muhammad; Abbasi, Bilal Haider; Mohammad, Ijaz; Fazal, Lubna

    2011-08-01

    The main objective of the current study is to investigate the potential of Carica papaya leaves extracts against Dengue fever in 45 year old patient bitten by carrier mosquitoes. For the treatment of Dengue fever the extract was prepared in water. 25 mL of aqueous extract of C. papaya leaves was administered to patient infected with Dengue fever twice daily i.e. morning and evening for five consecutive days. Before the extract administration the blood samples from patient were analyzed. Platelets count (PLT), White Blood Cells (WBC) and Neutrophils (NEUT) decreased from 176×10(3)/µL, 8.10×10(3)/µL, 84.0% to 55×10(3)/µL, 3.7×10(3)/µL and 46.0%. Subsequently, the blood samples were rechecked after the administration of leaves extract. It was observed that the PLT count increased from 55×10(3)/µL to 168×10(3)/µL, WBC from 3.7×10(3)/µL to 7.7×10(3)/µL and NEUT from 46.0% to 78.3%. From the patient feelings and blood reports it showed that Carica papaya leaves aqueous extract exhibited potential activity against Dengue fever. Furthermore, the different parts of this valuable specie can be further used as a strong natural candidate against viral diseases.

  20. Dengue fever treatment with Carica papaya leaves extracts

    Institute of Scientific and Technical Information of China (English)

    Nisar Ahmad; Hina Fazal; Muhammad Ayaz; Bilal Haider Abbasi; Ijaz Mohammad; Lubna Fazal

    2011-01-01

    The main objective of the current study is to investigate the potential of Carica papaya leaves extracts against Dengue fever in 45 year old patient bitten by carrier mosquitoes. For the treatment of Dengue fever the extract was prepared in water. 25 mL of aqueous extract of C. papaya leaves was administered to patient infected with Dengue fever twice daily i.e. morning and evening for five consecutive days. Before the extract administration the blood samples from patient were analyzed. Platelets count (PLT), White Blood Cells (WBC) and Neutrophils (NEUT) decreased from 176×103/μL, 8.10×10 3/μL, 84.0% to 55×10 3/μL, 3.7×10 3/μL and 46.0%. Subsequently, the blood samples were rechecked after the administration of leaves extract. It was observed that the PLT count increased from 55×103/μL to 168×10 3/μL, WBC from 3.7×10 3/μL to 7.7×10 3/μL and NEUT from 46.0% to 78.3%. From the patient feelings and blood reports it showed that Caricapapaya leaves aqueous extract exhibited potential activity against Dengue fever. Furthermore, the different parts of this valuable specie can be further used as a strong natural candidate against viral diseases.

  1. Dengue hemorrhagic fever in a peripheral blood stem cell transplant recipient: the first case report

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    Jirayu Visuthranukul

    2009-11-01

    Full Text Available Dengue infection, a mosquito-borne infectious disease in tropical and subtropical areas, has recently become an emerging global disease. Clinical course of dengue infection may be unfavorable in immunocompromised patients. In this report, we present a 16-year-old female patient with acute myeloid leukemia and receiving allogeneic peripheral blood stem cell transplant who was hospitalized at King Chulalongkorn Memorial Hospital, Bangkok, Thailand, due to fever, headache, and myalgia for one day. During hospitalization, she developed capillary leakage syndrome and progressive thrombocytopenia. A diagnosis of dengue hemorrhagic fever was made and confirmed by positive dengue serology and polymerase chain reaction testing. She made a full recovery 14 days after hospitalization. In conclusion, this is the first reported case of dengue hemorrhagic fever in a peripheral blood stem cell transplant recipient. In addition, we review all previous reports of dengue infection in organ transplant recipients.

  2. The impact of transgenic mosquitoes on dengue virulence to humans and mosquitoes.

    Science.gov (United States)

    Medlock, Jan; Luz, Paula M; Struchiner, Claudio J; Galvani, Alison P

    2009-10-01

    Dengue is a major public health concern in the tropics and subtropics. Innovative transgenic strategies to render Aedes aegypti mosquitoes, the primary vector of dengue, incompetent for dengue transmission are under development. We modeled the evolutionary impact of different transgenic mosquito strategies on dengue-induced mortality, that is, dengue virulence, to both humans and mosquitoes. This model incorporates various evolutionary trade-offs in dengue virus epidemiological traits, for example, a trade-off between dengue transmission rate and its virulence to humans. Our results indicate that strategies that block transmission or reduce mosquito biting impose selection on dengue virulence in humans. This selection can be for either higher or lower virulence, depending on the interaction between the effect of the transgene and the trade-offs in epidemiological traits, highlighting the need for detailed quantitative data to understand more fully the impact of mosquito transgenesis on dengue virulence. Dengue virulence in mosquitoes can be selected on by transgenic strategies of blocking transmission, decreased mosquito biting, increased mosquito background mortality, and increased mosquito infection-induced mortality. Our results suggest that dengue control strategies that raise mosquito background mortality or mosquito infection-induced mortality pose less risk of causing increased virulence to humans than strategies that block transmission or reduce mosquito biting.

  3. Association of Mean Platelet Volume with Severity, Serology & Treatment Outcome in Dengue Fever: Prognostic Utility.

    Science.gov (United States)

    Sharma, Kritika; Yadav, Ajay

    2015-11-01

    Dengue is the most rapidly spreading mosquito-borne viral disease in the world. Dengue fever (DF) with its severe manifestations such as dengue haemorrhagic fever (DHF) and dengue shock syndrome (DSS) has emerged as a major public health problem of international concern. Thrombocytopenia and bleeding are common complications of dengue fever, hence besides platelet counts, there is a need to assess the role of mean platelet volume. Studying association of mean platelet volume (MPV) with severity, serology & treatment outcome to assess its prognostic utility, which can be of great help in limiting morbidity & mortality associated with dengue fever. The present study was conducted in Central Pathology Lab of SMS Medical College & Hospital, Jaipur, Rajasthan from the period of March 2013 till October 2013. Blood samples were collected from 200 patients with NS 1 Antigen positivity experiencing febrile illness, clinically consistent with dengue infection. Evaluation of platelet counts, MPV, IgM and IgG antibodies was done in all these cases. Categorical data were presented as numbers (percent) and were compared among groups using Chi-square test. Groups compared for demographic data were presented as mean and standard deviation and were compared using student t-test, ANOVA and Post-Hoc Test, Tukey Test using SPSS, version 20 for Windows. A total of 200 Dengue fever cases were studied. Out of which, 68% cases were of DF, 23% DHF & 9% DSS i.e. classical dengue fever was most common presentation. Maximum (44%) cases were in age group of 15-24 years. Fever was the presenting complaint in all cases (100%). 98% cases of dengue had thrombocytopenia. MPV showed no significant correlation with severity, serology & treatment outcome, thus excluding its role in dengue cases. Mean platelet volume is not important as prognostic parameter in dengue fever.

  4. Retrospective search for dengue vector mosquito Aedes albopictus in areas visited by a German traveler who contracted dengue in Japan

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    Mutsuo Kobayashi

    2014-09-01

    Full Text Available 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.

  5. Unusual Presentation of Dengue Fever Leading to Unnecessary Appendectomy.

    Science.gov (United States)

    Kumar, Lovekesh; Singh, Mahendra; Saxena, Ashish; Kolhe, Yuvraj; Karande, Snehal K; Singh, Narendra; Venkatesh, P; Meena, Rambabu

    2015-01-01

    Dengue fever is the most important arbovirus illness with an estimated incidence of 50-100 million cases per year. The common symptoms of dengue include fever, rash, malaise, nausea, vomiting, and musculoskeletal pain. Dengue fever may present as acute abdomen leading to diagnostic dilemma. The acute surgical complications of dengue fever include acute pancreatitis, acute acalculous cholecystitis, nonspecific peritonitis, and acute appendicitis. We report a case of dengue fever that mimicked acute appendicitis leading to unnecessary appendectomy. A careful history examination for dengue-related signs, and serial hemogram over the first 3-4 days of disease may prevent unnecessary appendectomy.

  6. Unusual Presentation of Dengue Fever Leading to Unnecessary Appendectomy

    Directory of Open Access Journals (Sweden)

    Lovekesh Kumar

    2015-01-01

    Full Text Available Dengue fever is the most important arbovirus illness with an estimated incidence of 50–100 million cases per year. The common symptoms of dengue include fever, rash, malaise, nausea, vomiting, and musculoskeletal pain. Dengue fever may present as acute abdomen leading to diagnostic dilemma. The acute surgical complications of dengue fever include acute pancreatitis, acute acalculous cholecystitis, nonspecific peritonitis, and acute appendicitis. We report a case of dengue fever that mimicked acute appendicitis leading to unnecessary appendectomy. A careful history examination for dengue-related signs, and serial hemogram over the first 3-4 days of disease may prevent unnecessary appendectomy.

  7. Unusual Presentation of Dengue Fever Leading to Unnecessary Appendectomy

    Science.gov (United States)

    Kumar, Lovekesh; Singh, Mahendra; Saxena, Ashish; Kolhe, Yuvraj; Karande, Snehal K.; Singh, Narendra; Venkatesh, P.; Meena, Rambabu

    2015-01-01

    Dengue fever is the most important arbovirus illness with an estimated incidence of 50–100 million cases per year. The common symptoms of dengue include fever, rash, malaise, nausea, vomiting, and musculoskeletal pain. Dengue fever may present as acute abdomen leading to diagnostic dilemma. The acute surgical complications of dengue fever include acute pancreatitis, acute acalculous cholecystitis, nonspecific peritonitis, and acute appendicitis. We report a case of dengue fever that mimicked acute appendicitis leading to unnecessary appendectomy. A careful history examination for dengue-related signs, and serial hemogram over the first 3-4 days of disease may prevent unnecessary appendectomy. PMID:26167314

  8. 2008-2009年四川省登革热蚊媒监测结果分析%Analysis on the surveillance results of mosquito vectors of dengue fever from 2008 to 2009 in Sichuan province

    Institute of Scientific and Technical Information of China (English)

    曹一鸥; 刘学成; 祝小平; 张佳珂; 钱薇萍; 栾荣生

    2011-01-01

    Objective To investigate the distribution of mosquito vectors of dengue fever in Sichuan province for providing data for the prevention and control of the epidemic.Methods Surveillance on the vector of dengue fever, Aedes albopictus, was conducted all over the province from 2008 to 2009, with the dengue virus isolated and the density of mosquito vectors analyzed.Results Statistics showed that the container index (CI) of 19 surveillance sites was 24.05% with an adult Ae.albopictus density of 5.69 per person per hour.It was seen that waste tyres had a highest CI (48.77%), followed by some special places which had a CI and density of Ae.albopictus of 40.74% and 15.32 per person per hour, respectively.The peak CI appeared in July (30.60%),with the peak density of adult Ae.albopictus observed in August (7.94 per person per hour).It was found that the Ae.albopictus was the predominant species in most surveillance sites, with the composition ratio being between 26.88%-98.37%.There was a regional but not geographical location difference in the density ofAe.albopictus in the 19 surveillance points.No Ae.albopictus was found in the south of Ganzi prefecture.A sample of 4470 adult Ae.albopictus was collected in Longchang county, Neijiang city with no dengue viruses isolated from them.Conclusion There exists an extensive distribution of Ae.albopictus in the Szeehwan Basin.An epidemic outbreak may occur once there is a case of dengue fever in the area.So surveillance on dengue needs to be strengthened.%目的 调查四川省登革热媒介伊蚊的分布情况,为登革热的防治提供依据.方法 对全省2008-2009年登革热媒介伊蚊进行监测,分析蚊虫密度,分离登革热病毒.结果 19个监测点蚊幼虫的容器指数为24.05%,白纹伊蚊总密度为5.69只/人工小时.以废旧轮胎容器指数最高,为48.77%;特殊场所蚊幼虫容器指数和成蚊密度均较高,分别为40.74%和15.32只/人工小时;容器指数高峰在7月为30

  9. Pictorial Keys for the Identification of Mosquitoes (Diptera: Culicidae) Associated With Dengue Virus Transmission

    Science.gov (United States)

    2004-08-03

    mediovittatus. American Journal of Tropical Medicine and Hygiene, 39, 218–222. Gubler, D.J. (1997) Dengue and dengue hemorrhagic fever: its history and...Culicidae). Insecta Koreana, 19(1), 1–130. © 2004 Magnolia Press 9KEY TO MOSQUITOES 589...virus in Yap State, Federated States of Micronesia, and implication of Aedes hensilli as an epidemic vector. American Journal of Tropical Medicine

  10. [Population genetics of dengue virus and transmission of dengue fever].

    Science.gov (United States)

    Falcón-Lezama, Jorge; Sánchez-Burgos, Gilma Guadalupe; Ramos-Castañeda, José

    2009-01-01

    The endemic behavior of dengue fever in Mexico during the past five years is of major concern to every sector related with public health and the effort to control the transmission has been focused on vector control. However, regardless of the effectiveness of the intervention measures it is important to know which elements determine dengue transmission. With regard to the molecular basis for dengue transmission, a great deal of progress has been made due to the introduction of genomic and bioinformatic approaches. The goal of this review is to describe the most recent developments in this area with emphasis on the Mexican situation.

  11. An Unusual Case of Osteonecrosis of Jaw associated with Dengue fever and Periodontitis.

    Science.gov (United States)

    Indurkar, Maya S; Sethi, Rohan

    2015-02-01

    Osteonecrosis is a disorder occurring rarely in the jaw. Dengue fever is a common mosquito-borne disease prevalent in many countries including India. The following report presents an interesting case of maxillary osteonecrosis in a middle aged male with history of dengue infection. We also diagnosed symptoms of chronic periodontitis in the patient, which may have potentiated the necrosis. This case report will describe a novel clinical presentation and management of osteonecrosis of jaw (ONJ) of unknown origin and a possible pathogenesis explaining the association of ONJ with dengue fever and periodontitis. This article is protected by copyright. All rights reserved.

  12. Use of optical coherence tomography to evaluate visual acuity and visual field changes in dengue fever.

    Science.gov (United States)

    Rhee, Taek Kwan; Han, Jung Il

    2014-02-01

    Dengue fever is a viral disease that is transmitted by mosquitoes and affects humans. In rare cases, dengue fever can cause visual impairment, which usually occurs within 1 month after contracting dengue fever and ranges from mild blurring of vision to severe blindness. Visual impairment due to dengue fever can be detected through angiography, retinography, optical coherence tomography (OCT) imaging, electroretinography, event electroencephalography (visually evoked potentials), and visual field analysis. The purpose of this study is to report changes in the eye captured using fluorescein angiography, indocyanine green, and OCT in 3 cases of dengue fever visual impairment associated with consistent visual symptoms and similar retinochoroidopathic changes. The OCT results of the three patients with dengue fever showed thinning of the outer retinal layer and disruption of the inner segment/outer segment (IS/OS) junction. While thinning of the retina outer layer is an irreversible process, disruption of IS/OS junction is reported to be reversible. Follow-up examination of individuals with dengue fever and associated visual impairment should involve the use of OCT to evaluate visual acuity and visual field changes in patients with acute choroidal ischemia.

  13. Targeting educational campaigns for prevention of malaria and dengue fever: an assessment in Thailand.

    Science.gov (United States)

    Brusich, Macy; Grieco, John; Penney, Naomi; Tisgratog, Rungarun; Ritthison, Wanapa; Chareonviriyaphap, Theeraphap; Achee, Nicole

    2015-01-23

    The current study assessed the knowledge, attitudes, and practices (KAP) of at-risk populations for malaria and/or dengue fever in relation to mosquito exposure and household mosquito control practices. Specific objectives included comparison of individual and household level health practices between a rural and urban setting in Thailand. Findings are intended to guide Thailand Ministry of Health educational campaigns targeting arthropod-borne disease. A mixed method design was employed using a forced choice and open-ended questionnaire to assess KAP of participants seeking point-of-care treatment for malaria and/or dengue fever at government health-care facilities. Following informed consent, household construction characterization (percent eave gap, floor, wall, and roof material) and mosquito collections both indoors (using aspiration) and outside (using traps) were conducted at a subsample of participant homes. All mosquitoes were identified to genus and anopheline and aedine samples processed for potential pathogen infection. A total of 64 participants were recruited from both study sites; 62 categorized as malaria symptomology and 2 categorized as dengue across all study healthcare facilities. Significant associations between study site and household construction were indicated. Trends also identified household level practices and both occupation and household construction regarding type of mosquito control products purchased and the abundance of mosquitoes in sampled homes. Overall, Ministry of Health information from education campaigns regarding malaria and dengue fever strategies is reaching the intended target populations at the study sites. Participants are aware of the presence of mosquitoes and that they serve as the potential vector for transmitting malaria and dengue fever diseases. However, specific knowledge gaps were also identified in each study site that may influence exposure to infected mosquitoes. Findings from this study are intended to

  14. Dengue-1 Virus Isolation during First Dengue Fever Outbreak on Easter Island, Chile

    OpenAIRE

    Perret, Cecilia; Abarca, Katia; Ovalle, Jimena; Ferrer, Pablo; Godoy, Paula; Olea, Andrea; Aguilera, Ximena; Ferrés, Marcela

    2003-01-01

    Dengue virus was detected for the first time in Chile, in an outbreak of dengue fever on Easter Island. The virus was isolated in tissue culture and characterized by reverse transcription–polymerase chain reaction as being dengue type 1.

  15. Dengue-1 virus isolation during first dengue fever outbreak on Easter Island, Chile.

    Science.gov (United States)

    Perret, Cecilia; Abarca, Katia; Ovalle, Jimena; Ferrer, Pablo; Godoy, Paula; Olea, Andrea; Aguilera, Ximena; Ferrés, Marcela

    2003-11-01

    Dengue virus was detected for the first time in Chile, in an outbreak of dengue fever on Easter Island. The virus was isolated in tissue culture and characterized by reverse transcription-polymerase chain reaction as being dengue type 1.

  16. Evaluation of fifteen local plants as larvicidal agents against an Indian strain of dengue fever mosquito, Aedes aegypti L. (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    Sarita eKumar

    2012-04-01

    Full Text Available The adverse effects of chemical insecticides-based intervention measures for the control of mosquito vectors have received wide public apprehension because of several problems like insecticide resistance, resurgence of pest species, environmental pollution, toxic hazards to humans and non-target organisms. These problems have necessitated the need to explore and development of alternative strategies using eco-friendly, environmentally safe, bio-degradable plant products which are non-toxic to non target organisms too. In view of this, fifteen plants were collected from local areas in New Delhi, India. Different parts of these plants were separated, dried, mechanically grinded and sieved to get fine powder. The 200 g of each part was soaked in 1000 mL of different solvents separately and the crude extracts, thus formed, were concentrated using a vacuum evaporator at 45ºC under low pressure. Each extract was screened to explore its potential as a mosquito larvicidal agent against early fourth instars of dengue vector, Aedes aegypti using WHO protocol. The preliminary screening showed that only ten plants possessed larvicidal potential as they could result in 100% mortality at 1000 ppm. Further evaluation of the potential larvicidal extracts established the hexane leaf extracts of Lantana camara to be most effective extracts exhibiting a significant LC50 value of 30.71 ppm while the Phyllanthus emblica fruit extracts were found to be least effective with an LC50 value of 298.93 ppm. The extracts made from different parts of other five plants; Achyranthes aspera, Zingiber officinalis, Ricinus communis, Trachyspermun ammi and Cassia occidentalis also possessed significant larvicidal potential with LC¬50 values ranging from 55.0 to 74.67 ppm. Other three extracts showed moderate toxicity against Aedes aegypti larvae. Further investigations would be needed to isolate and identify the primary component responsible for the larvicidal efficiency of the

  17. Mosquito, adult (image)

    Science.gov (United States)

    This illustration shows an adult southern house mosquito. This mosquito feeds on blood and is the carrier of many diseases, such as encephalitis, West Nile, dengue fever, yellow fever, and others. ( ...

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

    Directory of Open Access Journals (Sweden)

    David F. Attaway

    2014-11-01

    Full Text Available 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 with- in Kenya. Similarity Search develops a risk map by combining environmental susceptibility analysis and geographical infor- mation 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 epi- demic 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 bio- climatic variables, elevation and mosquito habitat increased the efficiency and effectiveness of the dengue fever risk mapping process.

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

    Science.gov (United States)

    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.

  20. Longitudinal study of Thai people media exposure, knowledge, and behavior on dengue fever prevention and control.

    Science.gov (United States)

    Boonchutima, Smith; Kachentawa, Kirati; Limpavithayakul, Manasanun; Prachansri, Anan

    2017-03-09

    Dengue hemorrhagic fever is transmitted through a bite by a dengue -infected Aedes aegypti mosquito. It was first reported in the mid -20th century in Thailand, and since then its epidemiology has been of great concern and has spread all across the country. The alarming incidence of dengue posed a serious threat to human health in all major cities of Thailand. This study was aimed at identifying the level of awareness of dengue fever in Thai population knowledge for prevention and control, and most importantly contribution of media in educating masses for dengue control measures. It is longitudinal in nature and was conducted in 25 provinces of Thailand during 2013-2015. Approximately 7772 respondents participated in this study, with the selection of provinces based on considerations like population, prevalence and demography. A pre-tested structured questionnaire was used to collect information relevant to study participants' demographic profile, pre-existing knowledge about dengue fever and its reinforcement through media, and population attitudes toward prevention and control. Over the period of three years, a positive trend was revealed relevant to the contribution of media in educating and reminding the Thai population of dengue, without any uniformity or powerful campaigns. Based on the results drawn from this study, we conclude that despite the measures undertaken to prevent dengue fever, there is insufficient media exposure. An interdisciplinary approach involving the community participation, media, and government is needed to overcome dengue threat in Thailand.

  1. Neurological complications of dengue fever: Experience from a tertiary center of north India.

    Science.gov (United States)

    Verma, Rajesh; Sharma, Pawan; Garg, Ravindra Kumar; Atam, Veerendra; Singh, Maneesh Kumar; Mehrotra, Hardeep Singh

    2011-10-01

    Dengue, an acute viral disease transmitted by Aedes mosquitoes, is highly endemic in many tropical and subtropical areas of the world. Neurological complications of dengue infection have been observed more frequently in the recent past and some studies highlighted varied neurological complications arising in the course of dengue illness. In this retrospective study, we report various neurological complications observed during the last 2 years in patients of dengue fever. The patients presenting with neurological complications with positive serology (IgM antibody) for dengue infection were consecutively recruited from the Department of Neurology/Medicine from a tertiary center of Lucknow, India. These patients were subjected to a detailed clinical evaluation, laboratory assessment including blood count, hematocrit, coagulation parameters, biochemical assays, serology for dengue fever, enzyme-linked immunosorbent assay for human immunodeficiency virus and other relevant investigations. Twenty-six patients with neurological complications associated with confirmed dengue infection were observed during the last 2 years. Eighteen of these patients were male. Of the 26 patients, 10 patients were suffering from brachial neuritis, four patients had encephalopathy, three patients were consistent with the diagnosis of Guillain Barre syndrome, three patients had hypokalemic paralysis associated with dengue fever and two patients had acute viral myositis. Opsoclonus-myoclonus syndrome was diagnosed in two patients, myelitis in one patient and acute disseminated encephalo-myelitis also in one patient. Dengue fever was associated with widespread neurological complications. Brachial neuritis and opsoclonus-myoclonus syndrome were observed for the first time in this study.

  2. Human to mosquito transmission of dengue viruses

    Directory of Open Access Journals (Sweden)

    Lauren B Carrington

    2014-06-01

    Full Text Available The successful transmission of dengue virus from a human host to a mosquito vector requires a complex set of factors to align. It is becoming increasingly important to improve our understanding of the parameters that shape the human to mosquito component of the transmission cycle so that vaccines and therapeutic anti-virals can be fully evaluated and epidemiological models refined. Here we describe these factors, and discuss the biological and environmental impacts and demographic changes that are influencing these dynamics. Specifically, we examine features of the human infection required for the mosquito to acquire the virus via natural blood feeding, as well as the biological and environmental factors that influence a mosquito’s susceptibility to infection, up to the point that they are capable of transmitting the virus to a new host.

  3. Dengue Fever with rectus sheath hematoma: a case report.

    Science.gov (United States)

    Sharma, Anurag; Bhatia, Sonia; Singh, Rajendra Pratap; Malik, Gaurav

    2014-04-01

    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.

  4. Dengue fever with rectus sheath hematoma: A case report

    Directory of Open Access Journals (Sweden)

    Anurag Sharma

    2014-01-01

    Full Text Available 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.

  5. Dengue vector mosquitos at a tourist attraction, Ko Samui, in 1995.

    Science.gov (United States)

    Thavara, U; Tawatsin, A; Phan-Urai, P; Ngamsuk, W; Chansang, C; Liu, M; Li, Z

    1996-03-01

    On Ko Samui, Thailand there were two epidemics of dengue hemorrhagic fever (DHF) in 1966 and 1967, followed by endemics up to 1994. Aedes aegypti and Aedes albopictus were the vectors. From January to July 1995, 51 cases of DHF were reported, out of these were many foreigners who still suffer from dengue fever and return home with negative impression. We carried out an entomological survey around the island and collected the mosquitos to detect dengue virus by digoxigenin-cDNA probe. The data revealed that Aedes aegypti and Aedes albopictus still were abundant and some were infected with dengue virus. Visual larval survey indices (HI, CI and BI) were 90.4, 61.3 and 301.3 respectively. Biting rate (BR) of Aedes mosquitos was high, the average indoor and outdoor BR were 9.7 and 100.8 mosquitos/man-hour. From 13 pools of mosquitos, 8 strains of dengue virus were detected (61.5%). The results may encourage the local authorities to improve vector surveillance and control before the famous island becomes an unpleasant island.

  6. Dengue Fever in the United States

    Centers for Disease Control (CDC) Podcasts

    2012-04-09

    Dr. Amesh Adalja, an associate at the Center for Biosecurity and clinical assistant professor at the University of Pittsburgh School, of Medicine, discusses dengue fever outbreaks in the United States.  Created: 4/9/2012 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 4/16/2012.

  7. Dengue and the risk of urban yellow fever reintroduction in São Paulo State, Brazil

    Directory of Open Access Journals (Sweden)

    Massad Eduardo

    2003-01-01

    Full Text Available OBJECTIVE: To propose a mathematical method for the estimation of the Basic Reproduction Number, R0, of urban yellow fever in a dengue-infested area. METHODS: The method is based on the assumption that, as the same vector (Aedes aegypti causes both infections, all the quantities related to the mosquito, estimated from the initial phase of dengue epidemic, could be applied to yellow fever dynamics. It is demonstrated that R0 for yellow fever is, on average, 43% lower than that for dengue. This difference is due to the longer dengue viremia and its shorter extrinsic incubation period. RESULTS: In this study the analysis was expanded to the epidemiological situation of dengue in São Paulo in the year 2001. The total number of dengue cases increased from 3,582 in 2000 to 51,348 in 2001. It was then calculated R0 for yellow fever for every city which have shown R0 of dengue greater than 1. It was also estimated the total number of unprotected people living in highly risky areas for urban yellow fever. CONCLUSIONS: Currently there is a great number of non-vaccinated people living in Aedes aegypti infested area in the state of São Paulo.

  8. The cross wavelet analysis of dengue fever variability influenced by meteorological conditions

    Science.gov (United States)

    Lin, Yuan-Chien; Yu, Hwa-Lung; Lee, Chieh-Han

    2015-04-01

    The multiyear variation of meteorological conditions induced by climate change causes the changing diffusion pattern of infectious disease and serious epidemic situation. Among them, dengue fever is one of the most serious vector-borne diseases distributed in tropical and sub-tropical regions. Dengue virus is transmitted by several species of mosquito and causing lots amount of human deaths every year around the world. The objective of this study is to investigate the impact of meteorological variables to the temporal variation of dengue fever epidemic in southern Taiwan. Several extreme and average indices of meteorological variables, i.e. temperature and humidity, were used for this analysis, including averaged, maximum and minimum temperature, and average rainfall, maximum 1-hr rainfall, and maximum 24-hr rainfall. This study plans to identify and quantify the nonlinear relationship of meteorological variables and dengue fever epidemic, finding the non-stationary time-frequency relationship and phase lag effects of those time series from 1998-2011 by using cross wavelet method. Results show that meteorological variables all have a significant time-frequency correlation region to dengue fever epidemic in frequency about one year (52 weeks). The associated phases can range from 0 to 90 degrees (0-13 weeks lag from meteorological factors to dengue incidences). Keywords: dengue fever, cross wavelet analysis, meteorological factor

  9. Dengue and the risk of urban yellow fever reintroduction in São Paulo State, Brazil

    Directory of Open Access Journals (Sweden)

    Eduardo Massad

    2003-08-01

    Full Text Available OBJECTIVE: To propose a mathematical method for the estimation of the Basic Reproduction Number, R0, of urban yellow fever in a dengue-infested area. METHODS: The method is based on the assumption that, as the same vector (Aedes aegypti causes both infections, all the quantities related to the mosquito, estimated from the initial phase of dengue epidemic, could be applied to yellow fever dynamics. It is demonstrated that R0 for yellow fever is, on average, 43% lower than that for dengue. This difference is due to the longer dengue viremia and its shorter extrinsic incubation period. RESULTS: In this study the analysis was expanded to the epidemiological situation of dengue in São Paulo in the year 2001. The total number of dengue cases increased from 3,582 in 2000 to 51,348 in 2001. It was then calculated R0 for yellow fever for every city which have shown R0 of dengue greater than 1. It was also estimated the total number of unprotected people living in highly risky areas for urban yellow fever. CONCLUSIONS: Currently there is a great number of non-vaccinated people living in Aedes aegypti infested area in the state of São Paulo.

  10. Ecological factors associated with dengue fever in a central highlands Province, Vietnam

    Directory of Open Access Journals (Sweden)

    Phan Thao TT

    2011-06-01

    Full Text Available Abstract Background Dengue is a leading cause of severe illness and hospitalization in Vietnam. This study sought to elucidate the linkage between climate factors, mosquito indices and dengue incidence. Methods Monthly data on dengue cases and mosquito larval indices were ascertained between 2004 and 2008 in the Dak Lak province (Vietnam. Temperature, sunshine, rainfall and humidity were also recorded as monthly averages. The association between these ecological factors and dengue was assessed by the Poisson regression model with adjustment for seasonality. Results During the study period, 3,502 cases of dengue fever were reported. Approximately 72% of cases were reported from July to October. After adjusting for seasonality, the incidence of dengue fever was significantly associated with the following factors: higher household index (risk ratio [RR]: 1.66; 95% confidence interval [CI]: 1.62-1.70 per 5% increase, higher container index (RR: 1.78; 95% CI: 1.73-1.83 per 5% increase, and higher Breteau index (RR: 1.57; 95% CI: 1.53-1.60 per 5 unit increase. The risk of dengue was also associated with elevated temperature (RR: 1.39; 95% CI: 1.25-1.55 per 2°C increase, higher humidity (RR: 1.59; 95% CI: 1.51-1.67 per 5% increase, and higher rainfall (RR: 1.13; 95% CI: 1.21-1.74 per 50 mm increase. The risk of dengue was inversely associated with duration of sunshine, the number of dengue cases being lower as the sunshine increases (RR: 0.76; 95% CI: 0.73-0.79 per 50 hours increase. Conclusions These data suggest that indices of mosquito and climate factors are main determinants of dengue fever in Vietnam. This finding suggests that the global climate change will likely increase the burden of dengue fever infection in Vietnam, and that intensified surveillance and control of mosquito during high temperature and rainfall seasons may be an important strategy for containing the burden of dengue fever.

  11. Dengue e dengue hemorrágico: aspectos do manejo na unidade de terapia intensiva Dengue and dengue hemorrhagic fever: management issues in an intensive care unit

    Directory of Open Access Journals (Sweden)

    Sunit Singhi

    2007-05-01

    Full Text Available OBJETIVOS: Descrever a epidemiologia, as características clínicas e o tratamento do dengue e das síndromes do choque associadas ao dengue. FONTES DOS DADOS: Para esta revisão de literatura, foi feita uma pesquisa no Pubmed e nos websites da Organização Mundial da Saúde (OMS e OPAS usando os termos dengue e síndrome do choque associada ao dengue. A informação foi complementada com a experiência pessoal dos autores. SÍNTESE DOS DADOS: O dengue é a mais importante doença viral transmitida por artrópodos em seres humanos. A doença se manifesta de diversas formas, variando desde uma síndrome viral não-diferenciada até febre hemorrágica e choque grave. O dengue é uma enfermidade autolimitada, não específica, caracterizada por febre, cefaléia, mialgia, e sintomas constitucionais. As formas mais graves (febre hemorrágica e síndrome do choque podem levar a um comprometimento multissistêmico e ao óbito. O diagnóstico precoce e um acompanhamento contínuo do agravamento e da resposta ao tratamento são necessários em todos os casos. A OMS recomenda uma abordagem escalonada para o manejo, adequada para as formas mais leves e para o choque precoce. Nas formas mais graves, é preciso uma abordagem agressiva de reanimação com fluidos e de suporte à falência de órgãos em pacientes em estado crítico. As pesquisas sobre as diferenças fisiopatológicas entre o choque do dengue e o choque séptico, seleção de fluidos, agentes inotrópicos e técnicas de suporte a órgãos podem beneficiar os pacientes em estado crítico. CONCLUSÕES: Não há uma terapia específica para infecções causadas pelo dengue. Um bom tratamento de suporte pode salvar vidas mas, em última análise, as iniciativas de controle do vetor e de prevenção contra picadas do mosquito podem trazer os maiores benefícios.OBJECTIVES: To describe the epidemiology, clinical features and treatment of dengue fever and dengue shock syndrome. SOURCES: To prepare

  12. Hemoterapia e febre Dengue Blood banking e Dengue fever

    Directory of Open Access Journals (Sweden)

    Estácio F. Ramos

    2008-02-01

    Full Text Available Dengue is an endemic/epidemic arboviral disease with a variable symptomatic benign course, but potentially fatal. Once in an inhabited area, the disease will exist forever, with the best achievement being to keep vectors suppressed and the disease under control. Tiger mosquitoes (aedes aegypti, aedes albopictus are active breeders and urban hunters, becoming resistant to pesticides. Global warming and population growth are propelling the disease worldwide at tropical and subtropical regions, victimizing new populations. Dengue virus is very infective, and has been transmitted by needlestick, intrapartum, through blood transfusion and mucosal contact with blood. One patient got dengue while undergoing bone marrow transplantation. We address the growing dengue epidemics in Brazil, with more than half a million official cases in 2007, to estimate the risks of transfusion transmitted dengue. Calculations however were surpassed by reality: the major Blood Center in Brazil (FHSP-USP has found dengue virus in one out of each thousand blood units. In 2007, industry sold 2,6 million disposable blood bags in Brazil. Plotting data from FHSP-USP to the whole country, 2600 blood units would have been infective. Through blood components, around 5000 patients must have received dengue virus intravenously. Beatty et al. estimated to be 1:1300 the risk for dengue transmission through blood transfusion in Puerto Rico, close to what has been demonstrated in Sao Paulo. Throughout Brazil, the average risk may be lower, but the epidemics grows towards a worst scenario. Whatever the risk is, it imposes that all blood units in Brazil (and wherever dengue is endemic must be EIA tested for dengue NS1 antigen. This marker appears early after infection, and the EIA testing platform is available at all blood banks. Also, donors must report febrile states up to two weeks after donation. Morbidity from dengue virus injected in hospitalized patients is unknown, but it may lead

  13. The effect of temperature and humidity on dengue virus propagation in Aedes aegypti mosquitos.

    Science.gov (United States)

    Thu, H M; Aye, K M; Thein, S

    1998-06-01

    The effect of temperature and relative humidity on dengue virus propagation in the mosquito as one of the possible contributing factors to dengue hemorrhagic fever (DHF) outbreaks was studied. Ae. aegypti mosquitos were reared under standard conditions and inoculated intrathoracically with dengue virus. Virus propagation in the mosquitos was determined at the temperature and relative humidity of all 3 seasons of Yangon and for the simulated temperature and relative humidity of Singapore. The virus propagation was detected by direct fluorescent antibody technique (DFAT) with mosquito head squash and the virus titer was determined by plaque forming unit test (PFUT) in baby hamster kidney-21 cells. The results show that the infected mosquitos kept under the conditions of the rainy season and under the simulated conditions of Singapore had a significantly higher virus titer (p=<0.05) when compared with the other 2 seasons of Yangon. So it is thought that the temperature and relative humidity of the rainy season of Yangon and that of Singapore favors dengue virus propagation in the mosquito and is one of the contributing factors to the occurence of DHF outbreaks.

  14. Dengue hemorrhagic fever and acute hepatitis: a case report

    Directory of Open Access Journals (Sweden)

    Maria Paula Gomes Mourão

    Full Text Available Dengue fever is the world's most important viral hemorrhagic fever disease, the most geographically wide-spread of the arthropod-born viruses, and it causes a wide clinical spectrum of disease. We report a case of dengue hemorrhagic fever complicated by acute hepatitis. The initial picture of classical dengue fever was followed by painful liver enlargement, vomiting, hematemesis, epistaxis and diarrhea. Severe liver injury was detected by laboratory investigation, according to a syndromic surveillance protocol, expressed in a self-limiting pattern and the patient had a complete recovery. The serological tests for hepatitis and yellow fever viruses were negative. MAC-ELISA for dengue was positive.

  15. Dengue hemorrhagic fever and acute hepatitis: a case report

    Directory of Open Access Journals (Sweden)

    Maria Paula Gomes Mourão

    2004-12-01

    Full Text Available Dengue fever is the world's most important viral hemorrhagic fever disease, the most geographically wide-spread of the arthropod-born viruses, and it causes a wide clinical spectrum of disease. We report a case of dengue hemorrhagic fever complicated by acute hepatitis. The initial picture of classical dengue fever was followed by painful liver enlargement, vomiting, hematemesis, epistaxis and diarrhea. Severe liver injury was detected by laboratory investigation, according to a syndromic surveillance protocol, expressed in a self-limiting pattern and the patient had a complete recovery. The serological tests for hepatitis and yellow fever viruses were negative. MAC-ELISA for dengue was positive.

  16. Laboratory-confirmed dengue fever and chikungunya fever cases at the Narita Airport Quarantine Station in 2013.

    Science.gov (United States)

    Furuichi, Mieko; Makie, Toshio; Honma, Yasuko; Isoda, Takayoshi; Miyake, Satoru

    2015-01-01

    Fourteen patients were laboratory-confirmed cases of imported infectious diseases at the Narita Airport Quarantine Station in 2013. Blood tests were performed on 283 subjects suspected of having imported infectious diseases. Of these, 11 were diagnosed as having dengue fever (dengue) and 3 as having chikungunya fever (chikungunya) using real-time RT-PCR. The possible countries from which dengue virus infections were contracted were Thailand, Laos, Sri Lanka, and some other countries in Southeast Asia and South Asia. The 3 chikungunya cases were also diagnosed in individuals that returned from Southeast Asia. Most of the patients with dengue had a fever of over 38℃. The other symptoms were generalized fatigue, dull headache, pain behind the eyes, arthralgia, and digestive symptoms. Four of the patients were unaware of any mosquito bites. The information obtained from the confirmed cases showed that it is important to consider both the destination to which individuals travelled and the clinical symptoms, regardless of whether the subjects were aware of mosquito bites. The detection rate of chikungunya at the Quarantine Station was higher than that of dengue in all reported cases in Japan.

  17. Surveillance on mosquito vectors of dengue fever and dengue virus in Longgang district of Shenzhen city,2009-2011%深圳市龙岗区2009-2011年登革热媒介监测分析

    Institute of Scientific and Technical Information of China (English)

    周健明; 王德全; 林琳; 刘渠; 张起文

    2012-01-01

    目的 了解广东省深圳市龙岗区成蚊携带登革病毒状况与健康人群登革病毒抗体水平,为登革热的流行风险评估提供客观依据.方法 于2009-2011年对龙岗区10个街道和21个大运场馆进行蚊种构成及密度监测,检测成蚊携带登革病毒和健康人群的登革病毒IgG抗体水平.结果 2009-2011年龙岗区共捕获25 556只成蚊,其中东乡伊蚊和白纹伊蚊分别占2.45%与1.60%;学校和工地的诱蚊诱卵指数均高于平均水平,分别为18.34%和11.29%;不同生境成蚊密度以医院最高,达27.67只/灯;从2批伊蚊标本中检测有登革病毒,其中1批标本经测序分析与登革病毒Ⅱ型流行株同源性最高,达98%;检测884名健康人群中登革病毒IgG抗体阳性率为4.20%(37/884).结论 深圳市龙岗区伊蚊密度较低,但伊蚊携带登革病毒的效能较高,登革病毒已经在龙岗区自然界中存在.%Objective To explore the infection of dengue virus (DV) in mosquitoes and to determine the prevalence of serum anti-DV IgG antibody among healthy people in Longgang district of Shenzhen city for assessment of dengue fever epidemic risk. Methods Surveillance on the density and species of mosquito was conducted in 10 major subdis-tricts and 21 gymnasiums in Longgang district. The DV was identified with real-time reverse transcription PCR(RT-PCR) and anti-DV IgG antibody level in healthy population was detected with enzyme-linked immunosorbent assay (ELISA). Results A total of 25 556 mosquitoes were collected from 2009 to 2011 and among the mosquitoes Aedes to-goi and Aedes albopictus accounted for 2. 45% and 1. 60% .respectively. The indexes of mosquito and egg trap in schools (18. 34% ) and construction sites( 11. 29% ) were above average value. The average mosquito density in hospitals(27. 67 mosquitoes) was the highest among different sites. The real-time RT-PCR results showed that two positive samples were found and the maximum nucleotide

  18. Multilevel poisson regression modelling for determining factors of dengue fever cases in bandung

    Science.gov (United States)

    Arundina, Davila Rubianti; Tantular, Bertho; Pontoh, Resa Septiani

    2017-03-01

    Scralatina or Dengue Fever is a kind of fever caused by serotype virus which Flavivirus genus and be known as Dengue Virus. Dengue Fever caused by Aedes Aegipty Mosquito bites who infected by a dengue virus. The study was conducted in 151 villages in Bandung. Health Analysts believes that there are two factors that affect the dengue cases, Internal factor (individual) and external factor (environment). The data who used in this research is hierarchical data. The method is used for hierarchical data modelling is multilevel method. Which is, the level 1 is village and level 2 is sub-district. According exploration data analysis, the suitable Multilevel Method is Random Intercept Model. Penalized Quasi Likelihood (PQL) approach on multilevel Poisson is a proper analysis to determine factors that affecting dengue cases in the city of Bandung. Clean and Healthy Behavior factor from the village level have an effect on the number of cases of dengue fever in the city of Bandung. Factor from the sub-district level has no effect.

  19. Knowledge, attitude and perception regarding dengue fever among university students of interior Sindh.

    Science.gov (United States)

    Bota, Rafaqat; Ahmed, Mushtaq; Jamali, Muhammad Salah; Aziz, Adnan

    2014-01-01

    Dengue is among the most common mosquito-borne viral diseases that affect humans. It has now become a major public health dilemma, annually affecting approximately 50-100 million people worldwide. This study aimed to assess the knowledge, attitude and perception of dengue fever among university students of interior Sindh. A cross-sectional study was conducted during the period of April-June 2012. Four hundred and fifty students were surveyed. A structured pre-tested questionnaire was used to collect data. The data were analyzed using SPSS version 17. Overall, 94.6% of participants (43.3% male and 56.7% female, p-value 0.03) reported that they had heard about dengue, and 58.6% of participants reported "Aedes mosquito" as a vector of dengue virus, with gender difference (37.5% male vs 62.5% females with p-value University for Health Sciences. Published by Elsevier Ltd. All rights reserved.

  20. Seir Model for Transmission of Dengue Fever in Selangor Malaysia

    Science.gov (United States)

    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.

  1. Mathematical model in controlling dengue transmission with sterile mosquito strategies

    Science.gov (United States)

    Aldila, D.; Nuraini, N.; Soewono, E.

    2015-09-01

    In this article, we propose a mathematical model for controlling dengue disease transmission with sterile mosquito techniques (SIT). Sterile male introduced from lab in to habitat to compete with wild male mosquito for mating with female mosquito. Our aim is to displace gradually the natural mosquito from the habitat. Mathematical model analysis for steady states and the basic reproductive ratio are performed analytically. Numerical simulation are shown in some different scenarios. We find that SIT intervention is potential to controlling dengue spread among humans population

  2. Imaginal Discs – A New Source of Chromosomes for Genome Mapping of the Yellow Fever Mosquito Aedes aegypti

    OpenAIRE

    Sharakhova, Maria V.; Vladimir A Timoshevskiy; Fan Yang; Sergei Iu Demin; Severson, David W; Sharakhov, Igor V

    2011-01-01

    Author Summary Dengue fever is an emerging health threat to as much as half of the human population around the world. No vaccines or drug treatments are currently available. Thus, disease prevention is largely based on efforts to control its major mosquito vector Ae. aegypti. Novel vector control strategies, such as population replacement with pathogen-incompetent transgenic mosquitoes, rely on detailed knowledge of the genome organization for the mosquito. However, the current genome assembl...

  3. Health beliefs and practices related to dengue fever: a focus group study.

    Directory of Open Access Journals (Sweden)

    Li Ping Wong

    Full Text Available 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 16(th December, 2011 and 12(th 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.

  4. Dengue fever mimicking acute appendicitis: A case report.

    Science.gov (United States)

    McFarlane, M E C; Plummer, J M; Leake, P A; Powell, L; Chand, V; Chung, S; Tulloch, K

    2013-01-01

    Dengue fever is an acute viral disease, which usually presents as a mild febrile illness. Patients with severe disease present with dengue haemorrhagic fever or dengue toxic shock syndrome. Rarely, it presents with abdominal symptoms mimicking acute appendicitis. We present a case of a male patient presenting with right iliac fossa pain and suspected acute appendicitis that was later diagnosed with dengue fever following a negative appendicectomy. A 13-year old male patient presented with fever, localized right-sided abdominal pain and vomiting. Abdominal ultrasound was not helpful and appendicectomy was performed due to worsening abdominal signs and an elevated temperature. A normal appendix with enlarged mesenteric nodes was found at surgery. Complete blood count showed thrombocytopenia with leucopenia. Dengue fever was now suspected and confirmed by IgM enzyme-linked immunosorbent assay against dengue virus. This unusual presentation of dengue fever mimicking acute appendicitis should be suspected during viral outbreaks and in patients with atypical symptoms and cytopenias on blood evaluation in order to prevent unnecessary surgery. This case highlights the occurrence of abdominal symptoms and complications that may accompany dengue fever. Early recognition of dengue fever mimicking acute appendicitis will avoid non-therapeutic operation and the diagnosis may be aided by blood investigations indicating a leucopenia, which is uncommon in patients with suppurative acute appendicitis. Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.

  5. Advances in the development of vaccines for dengue fever

    Directory of Open Access Journals (Sweden)

    Simmons M

    2012-05-01

    Full Text Available Monika Simmons1, Nimfa Teneza-Mora1, Robert Putnak21Viral and Rickettsial Diseases Department, Naval Medical Research Center, 2Division of Viral Diseases, Walter Reed Army Institute of Research, Silver Spring, MD, USAAbstract: Dengue fever is caused by the mosquito-borne dengue virus (DENV serotypes 1–4, and is the most common arboviral infection of humans in subtropical and tropical regions of the world. There are currently no prophylaxis or treatment options in the form of vaccines or antivirals, leaving vector control the only method of prevention. A particular challenge with DENV is that a successful vaccine has to be effective against all four serotypes without predisposing for antibody-mediated enhanced disease. In this review, we discuss the current lead vaccine candidates in clinical trials, as well as some second-generation vaccine candidates undergoing preclinical evaluation. In addition, we discuss DENV epidemiology, clinical disease and strategies used for Flavivirus antivirals in the past, the development of new DENV therapeutics, and their potential usefulness for prophylaxis and treatment.Keywords: tetravalent dengue vaccine, live attenuated vaccine, purified inactivated vaccine, DNA vaccine, antibody-dependent enhancement, antivirals

  6. Retrospective search for dengue vector mosquito Aedes albopictus in areas visited by a German traveler who contracted dengue in Japan.

    Science.gov (United States)

    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. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  7. Dengue virus identification by transmission electron microscopy and molecular methods in fatal dengue hemorrhagic fever.

    Science.gov (United States)

    Limonta, D; Falcón, V; Torres, G; Capó, V; Menéndez, I; Rosario, D; Castellanos, Y; Alvarez, M; Rodríguez-Roche, R; de la Rosa, M C; Pavón, A; López, L; González, K; Guillén, G; Diaz, J; Guzmán, M G

    2012-12-01

    Dengue virus is the most significant virus transmitted by arthropods worldwide and may cause a potentially fatal systemic disease named dengue hemorrhagic fever. In this work, dengue virus serotype 4 was detected in the tissues of one fatal dengue hemorrhagic fever case using electron immunomicroscopy and molecular methods. This is the first report of dengue virus polypeptides findings by electron immunomicroscopy in human samples. In addition, not-previously-documented virus-like particles visualized in spleen, hepatic, brain, and pulmonary tissues from a dengue case are discussed.

  8. T cell responses and dengue haemorrhagic fever.

    Science.gov (United States)

    Screaton, Gavin; Mongkolsapaya, Juthathip

    2006-01-01

    The enhancement of severe disease upon secondary infection makes dengue almost unique among infectious pathogens and presents a serious challenge to vaccine design. Several key observations have been made which shed light onto this phenomenon particularly that antibodies can enhance Fc receptor-dependent uptake of virus into macrophages thereby increasing virus replication. Furthermore there seems to be a relationship between the peak virus load and disease severity. However, a second key feature of dengue is that the life-threatening symptoms do not correlate with the period of high viraemia; instead they occur at a time when the virus load is in steep decline. The coincidence of severe disease manifestations with defervescence and virus control suggests that the symptoms may be a consequence of the immune response to the virus rather than virus induced cytopathology. One of the key elements in the immune response to viruses are T cells which can both secrete a host of inflammatory cytokines and also be directly cytotoxic to infected cells. There are a number of experimental models of T cell-induced immunopathology including in responses to viruses. Particularly interesting in this respect are models of RSV-induced immunopathology, which have direct relevance to vaccine design as a formalin-inactivated vaccine to RSV actually enhanced disease in children when they became naturally infected with RSV, an echo of the disease enhancement seen in dengue. We will present an analysis of CD8+ T cell responses to a number of novel T cell epitopes during dengue infection and also analyse the function and cytokine secretion of these cells. We suggest that an exaggerated and partially misdirected T cell response seen in secondary dengue infection may be part of the complex series of events leading to dengue haemorrhagic fever and shock.

  9. The place of health and the health of place: dengue fever and urban governance in Putrajaya, Malaysia.

    Science.gov (United States)

    Mulligan, K; Elliott, S J; Schuster-Wallace, C

    2012-05-01

    This case study investigates the connections among urban planning, governance and dengue fever in an emerging market context in the Global South. Key informant interviews were conducted with leading figures in public health, urban planning and governance in the planned city of Putrajaya, Malaysia. Drawing on theories of urban political ecology and ecosocial epidemiology, the qualitative study found the health of place - expressed as dengue-bearing mosquitoes and dengue fever in human bodies in the urban environment - was influenced by the place of health in a hierarchy of urban priorities.

  10. Serological Evidence of Dengue Fever Among Refugees, Hargeysa, Somalia

    Science.gov (United States)

    1989-01-01

    AD-A24 1 179 Q O0T!119910 j •___ C PUBLICATION REPORT 1602 84/89-90 SEROLOGICAL EVIDENCE OF DENGUE FEVER AMONG REFUGEES, HARGEYOA, SOMALIA BY Boulos...of Dengue Fever Among Refugees, Hargeysa, Somalia Boulos A.M. Botros, Douglas M. Watts, Atef K. Soliman, Adel W. Salib, Mahmoud I. Moussa, H. Mursal...Tukei PM 1982). Epidemic Dengue fever caused by Dengue tion, antibody demonstrated by the EIA, IFA, and HI type-2 virus in Kenya: Preliminary results

  11. Proteinuria during dengue fever in children.

    Science.gov (United States)

    Andries, Anne-Claire; Duong, Veasna; Cappelle, Julien; Ong, Sivuth; Kerleguer, Alexandra; Ly, Sowath; Tarantola, Arnaud; Horwood, Paul F; Sakuntabhai, Anavaj; Dussart, Philippe; Buchy, Philippe

    2017-02-01

    This study aimed to investigate proteinuria occurring during dengue disease in children and assess if measurement of this parameter can help physicians in the clinical management of patients. Proteinuria was assessed by dipstick and quantified by urine protein:creatinine ratio (UPCR) in samples from patients hospitalized with a confirmed dengue infection and in healthy controls. The dipstick tested positive in 42.9% of the patients presenting at hospital with dengue versus 20.0% in healthy controls. UPCR increased during the critical phase of the disease; peaking one week after fever onset then decreasing as the patients recovered. Patients with warnings signs or severe dengue were more likely to present with proteinuria detected by UPCR at the time of hospital admission compared to patients without warning signs. The sensitivity of this marker, however, was limited as only 16.1% of the patients with warning signs had proteinuria. Urine dipstick and UPCR do not seem to be very valuable for the triage of the patients at the time of the initial consultation but the observation of a decrease of the UPCR during the course of the illness appears to indicate an evolution towards recovery. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  12. Dengue fever in a liver-transplanted patient: a case report.

    Science.gov (United States)

    Weerakkody, Ranga Migara; Palangasinghe, Dhammika Randula; Dalpatadu, Kaluthanthri Patabandi Chamila; Rankothkumbura, Jeewan Pradeep; Cassim, Mohammed Rezni Nizam; Karunanayake, Panduka

    2014-11-21

    Dengue fever is one of the commonest mosquito-borne diseases in the tropics, and Sri Lanka is no exception. Despite its commonness, dengue fever has rarely been described among patients who have undergone transplantation. We report the case of a patient with dengue fever after liver transplantation, which, to the best of our knowledge, is the first such reported case outside Brazil. Our patient was a 46-year-old Sri Lakan man who presented to our institution two years after undergoing an ABO-compatible cadaveric liver transplant. At presentation, he had typical symptoms of dengue fever. He was taking prednisolone 5mg daily and tacrolimus 3mg twice daily as immunosuppression. Initial investigations showed thrombocytopenia and neutropenia that reached a nadir by day 7 of his illness. He had elevated liver enzymes as well. The diagnosis was confirmed on the basis of NS1 antigen detection by enzyme-linked immunosorbent assay. His blood cultures and polymerase chain reaction tests for cytomegalovirus were negative. He made an uneventful recovery and was discharged by day 9 of his illness. However, normalization of liver function took nearly two weeks. In three previously reported Brazilian cases of dengue after liver transplantation, the patients presented with dengue shock syndrome, in contrast to the relatively milder presentation of our patient. Because of the lack of case reports in the literature, it is difficult to ascertain the risk factors for severe dengue infection in transplants, but dengue fever reported in renal transplants sheds some light on them. High-dose steroids increase the risk of thrombocytopenia, whereas tacrolimus has been reported to prolong the duration of symptoms. Otherwise, dengue fever is a relatively mild illness in patients who have undergone renal transplantation, and renal allograft survival has been reported to be 86% following dengue fever. Dengue is a rarely reported infection in patients who have undergone transplantation. A high

  13. Dengue as a cause of acute undifferentiated fever in Vietnam

    NARCIS (Netherlands)

    Phuong, H.L.; de Vries, P.J.; Nga, T.T.T.; Giao, P.T.; Hung, L.Q.; Binh, T.Q.; Nam, N.V.; Nagelkerke, N.; Kager, P.A.

    2006-01-01

    Background: Dengue is a common cause of fever in the tropics but its contribution to the total burden of febrile illnesses that is presented to primary health facilities in endemic regions such as Vietnam, is largely unknown. We aimed to report the frequency of dengue as a cause of fever in Binh

  14. Dengue as a cause of acute undifferentiated fever in Vietnam

    NARCIS (Netherlands)

    Phuong, H.L.; de Vries, P.J.; Nga, T.T.T.; Giao, P.T.; Hung, L.Q.; Binh, T.Q.; Nam, N.V.; Nagelkerke, N.; Kager, P.A.

    2006-01-01

    Background: Dengue is a common cause of fever in the tropics but its contribution to the total burden of febrile illnesses that is presented to primary health facilities in endemic regions such as Vietnam, is largely unknown. We aimed to report the frequency of dengue as a cause of fever in Binh Thu

  15. Detection of the mosquito-borne flaviviruses, West Nile, Dengue, Saint Louis Encephalitis, Ilheus, Bussuquara, and Yellow Fever in free-ranging black howlers (Alouatta caraya) of Northeastern Argentina

    Science.gov (United States)

    Morales, María A.; Fabbri, Cintia M.; Zunino, Gabriel E.; Kowalewski, Martín M.; Luppo, Victoria C.; Enría, Delia A.; Levis, Silvana C.; Calderón, Gladys E.

    2017-01-01

    Several medically important mosquito-borne flaviviruses have been detected in Argentina in recent years: Dengue (DENV), St. Louis encephalitis (SLEV), West Nile (WNV) and Yellow Fever (YFV) viruses. Evidence of Bussuquara virus (BSQV) and Ilheus virus (ILHV) activity were found, but they have not been associated with human disease. Non-human primates can act as important hosts in the natural cycle of flaviviruses and serological studies can lead to improved understanding of virus circulation dynamics and host susceptibility. From July–August 2010, we conducted serological and molecular surveys in free–ranging black howlers (Alouatta caraya) captured in northeastern Argentina. We used 90% plaque-reduction neutralization tests (PRNT90) to analyze 108 serum samples for antibodies to WNV, SLEV, YFV, DENV (serotypes 1and 3), ILHV, and BSQV. Virus genome detection was performed using generic reverse transcription (RT)-nested PCR to identify flaviviruses in 51 antibody-negative animals. Seventy animals had antibodies for one or more flaviviruses for a total antibody prevalence of 64.8% (70/108). Monotypic (13/70, 19%) and heterotypic (27/70, 39%) patterns were differentiated. Specific neutralizing antibodies against WNV, SLEV, DENV-1, DENV-3, ILHV, and BSQV were found. Unexpectedly, the highest flavivirus antibody prevalence detected was to WNV with 9 (8.33%) monotypic responses. All samples tested by (RT)-nested PCR were negative for viral genome. This is the first detection of WNV-specific antibodies in black howlers from Argentina and the first report in free-ranging non-human primates from Latin-American countries. Given that no animals had specific neutralizing antibodies to YFV, our results suggest that the study population remains susceptible to YFV. Monitoring of these agents should be strengthened to detect the establishment of sylvatic cycles of flaviviruses in America and evaluate risks to wildlife and human health. PMID:28187130

  16. Detection of the mosquito-borne flaviviruses, West Nile, Dengue, Saint Louis Encephalitis, Ilheus, Bussuquara, and Yellow Fever in free-ranging black howlers (Alouatta caraya) of Northeastern Argentina.

    Science.gov (United States)

    Morales, María A; Fabbri, Cintia M; Zunino, Gabriel E; Kowalewski, Martín M; Luppo, Victoria C; Enría, Delia A; Levis, Silvana C; Calderón, Gladys E

    2017-02-01

    Several medically important mosquito-borne flaviviruses have been detected in Argentina in recent years: Dengue (DENV), St. Louis encephalitis (SLEV), West Nile (WNV) and Yellow Fever (YFV) viruses. Evidence of Bussuquara virus (BSQV) and Ilheus virus (ILHV) activity were found, but they have not been associated with human disease. Non-human primates can act as important hosts in the natural cycle of flaviviruses and serological studies can lead to improved understanding of virus circulation dynamics and host susceptibility. From July-August 2010, we conducted serological and molecular surveys in free-ranging black howlers (Alouatta caraya) captured in northeastern Argentina. We used 90% plaque-reduction neutralization tests (PRNT90) to analyze 108 serum samples for antibodies to WNV, SLEV, YFV, DENV (serotypes 1and 3), ILHV, and BSQV. Virus genome detection was performed using generic reverse transcription (RT)-nested PCR to identify flaviviruses in 51 antibody-negative animals. Seventy animals had antibodies for one or more flaviviruses for a total antibody prevalence of 64.8% (70/108). Monotypic (13/70, 19%) and heterotypic (27/70, 39%) patterns were differentiated. Specific neutralizing antibodies against WNV, SLEV, DENV-1, DENV-3, ILHV, and BSQV were found. Unexpectedly, the highest flavivirus antibody prevalence detected was to WNV with 9 (8.33%) monotypic responses. All samples tested by (RT)-nested PCR were negative for viral genome. This is the first detection of WNV-specific antibodies in black howlers from Argentina and the first report in free-ranging non-human primates from Latin-American countries. Given that no animals had specific neutralizing antibodies to YFV, our results suggest that the study population remains susceptible to YFV. Monitoring of these agents should be strengthened to detect the establishment of sylvatic cycles of flaviviruses in America and evaluate risks to wildlife and human health.

  17. Practices of Dengue Fever Prevention and the Associated Factors among the Orang Asli in Peninsular Malaysia.

    Science.gov (United States)

    Chandren, Josephine Rebecca; Wong, Li Ping; AbuBakar, Sazaly

    2015-01-01

    Dengue is prevalent among Malaysia's indigenous peoples, known as the Orang Asli, and it poses a serious health threat to them. The study aims to look at the socio-demographic factors, health beliefs, and knowledge about dengue and its association to dengue prevention practices among Orang Asli communities in Peninsular Malaysia. A cross-sectional survey was conducted in 16 randomly selected Orang Asli villages from eight states in Peninsular Malaysia from April 2012 until February 2013. A total of 560 Orang Asli were interviewed and 505 completed the survey. Slightly above half of the participants (n = 280, 55.4%) had a total dengue prevention score of 51-100 (of a possible score of 0-100). Multivariate analysis findings showed dengue knowledge, perceived barriers to perform dengue prevention, fogging frequency, and perceived susceptibility to dengue fever as significant factors associated to dengue prevention practices. Participants with a lower dengue knowledge score (score 0-18) were less likely (OR = 0.63, 95%CI = 0.44-0.92 vs. score 19-36, P = 0.015) to practice dengue prevention. Participants with low perceived barriers to prevent dengue (score of 1-5) were more likely (OR = 2.06, 95%CI = 1.21-3.53, vs. score of 6-10, P = 0.008) to practice dengue prevention. Villages that were not fogged (OR = 0.49, 95%CI = 0.24-0.99, P = 0.045) or rarely fogged (OR = 0.40, 95%CI = 0.22-0.75, P = 0.004) had lower dengue prevention practices than villages that were fogged often. Participants with low perceived susceptibility of acquiring dengue (score of 1-5) were less likely (OR = 0.54, 95%CI = 0.33-0.89 vs. score of 6-10, P = 0.018) to practice dengue prevention measures. Findings imply that educational and health programmes should focus on enhancing dengue knowledge and perceived susceptibility of acquiring dengue and reducing perceived barriers to performing dengue prevention practices among the Orang Asli. More outreach on mosquito control campaigns should be carried

  18. Practices of Dengue Fever Prevention and the Associated Factors among the Orang Asli in Peninsular Malaysia.

    Directory of Open Access Journals (Sweden)

    Josephine Rebecca Chandren

    Full Text Available Dengue is prevalent among Malaysia's indigenous peoples, known as the Orang Asli, and it poses a serious health threat to them. The study aims to look at the socio-demographic factors, health beliefs, and knowledge about dengue and its association to dengue prevention practices among Orang Asli communities in Peninsular Malaysia.A cross-sectional survey was conducted in 16 randomly selected Orang Asli villages from eight states in Peninsular Malaysia from April 2012 until February 2013.A total of 560 Orang Asli were interviewed and 505 completed the survey. Slightly above half of the participants (n = 280, 55.4% had a total dengue prevention score of 51-100 (of a possible score of 0-100. Multivariate analysis findings showed dengue knowledge, perceived barriers to perform dengue prevention, fogging frequency, and perceived susceptibility to dengue fever as significant factors associated to dengue prevention practices. Participants with a lower dengue knowledge score (score 0-18 were less likely (OR = 0.63, 95%CI = 0.44-0.92 vs. score 19-36, P = 0.015 to practice dengue prevention. Participants with low perceived barriers to prevent dengue (score of 1-5 were more likely (OR = 2.06, 95%CI = 1.21-3.53, vs. score of 6-10, P = 0.008 to practice dengue prevention. Villages that were not fogged (OR = 0.49, 95%CI = 0.24-0.99, P = 0.045 or rarely fogged (OR = 0.40, 95%CI = 0.22-0.75, P = 0.004 had lower dengue prevention practices than villages that were fogged often. Participants with low perceived susceptibility of acquiring dengue (score of 1-5 were less likely (OR = 0.54, 95%CI = 0.33-0.89 vs. score of 6-10, P = 0.018 to practice dengue prevention measures.Findings imply that educational and health programmes should focus on enhancing dengue knowledge and perceived susceptibility of acquiring dengue and reducing perceived barriers to performing dengue prevention practices among the Orang Asli. More outreach on mosquito control campaigns should be

  19. Practices of Dengue Fever Prevention and the Associated Factors among the Orang Asli in Peninsular Malaysia

    Science.gov (United States)

    Chandren, Josephine Rebecca; Wong, Li Ping; AbuBakar, Sazaly

    2015-01-01

    Background Dengue is prevalent among Malaysia's indigenous peoples, known as the Orang Asli, and it poses a serious health threat to them. The study aims to look at the socio-demographic factors, health beliefs, and knowledge about dengue and its association to dengue prevention practices among Orang Asli communities in Peninsular Malaysia. Methods A cross-sectional survey was conducted in 16 randomly selected Orang Asli villages from eight states in Peninsular Malaysia from April 2012 until February 2013. Results A total of 560 Orang Asli were interviewed and 505 completed the survey. Slightly above half of the participants (n = 280, 55.4%) had a total dengue prevention score of 51–100 (of a possible score of 0–100). Multivariate analysis findings showed dengue knowledge, perceived barriers to perform dengue prevention, fogging frequency, and perceived susceptibility to dengue fever as significant factors associated to dengue prevention practices. Participants with a lower dengue knowledge score (score 0–18) were less likely (OR = 0.63, 95%CI = 0.44–0.92 vs. score 19–36, P = 0.015) to practice dengue prevention. Participants with low perceived barriers to prevent dengue (score of 1–5) were more likely (OR = 2.06, 95%CI = 1.21–3.53, vs. score of 6–10, P = 0.008) to practice dengue prevention. Villages that were not fogged (OR = 0.49, 95%CI = 0.24–0.99, P = 0.045) or rarely fogged (OR = 0.40, 95%CI = 0.22–0.75, P = 0.004) had lower dengue prevention practices than villages that were fogged often. Participants with low perceived susceptibility of acquiring dengue (score of 1–5) were less likely (OR = 0.54, 95%CI = 0.33–0.89 vs. score of 6–10, P = 0.018) to practice dengue prevention measures. Conclusion Findings imply that educational and health programmes should focus on enhancing dengue knowledge and perceived susceptibility of acquiring dengue and reducing perceived barriers to performing dengue prevention practices among the Orang Asli

  20. Neurological complications of dengue fever: Experience from a tertiary center of north India

    Directory of Open Access Journals (Sweden)

    Rajesh Verma

    2011-01-01

    Full Text Available Introduction: Dengue, an acute viral disease transmitted by Aedes mosquitoes, is highly endemic in many tropical and subtropical areas of the world. Neurological complications of dengue infection have been observed more frequently in the recent past and some studies highlighted varied neurological complications arising in the course of dengue illness. In this retrospective study, we report various neurological complications observed during the last 2 years in patients of dengue fever. Materials and Methods: The patients presenting with neurological complications with positive serology (IgM antibody for dengue infection were consecutively recruited from the Department of Neurology/Medicine from a tertiary center of Lucknow, India. These patients were subjected to a detailed clinical evaluation, laboratory assessment including blood count, hematocrit, coagulation parameters, biochemical assays, serology for dengue fever, enzyme-linked immunosorbent assay for human immunodeficiency virus and other relevant investigations. Results: Twenty-six patients with neurological complications associated with confirmed dengue infection were observed during the last 2 years. Eighteen of these patients were male. Of the 26 patients, 10 patients were suffering from brachial neuritis, four patients had encephalopathy, three patients were consistent with the diagnosis of Guillain Barre syndrome, three patients had hypokalemic paralysis associated with dengue fever and two patients had acute viral myositis. Opsoclonus-myoclonus syndrome was diagnosed in two patients, myelitis in one patient and acute disseminated encephalo-myelitis also in one patient. Conclusion: Dengue fever was associated with widespread neurological complications. Brachial neuritis and opsoclonus-myoclonus syndrome were observed for the first time in this study.

  1. Atypical Manifestations of Dengue Fever (DF) – Where Do We Stand Today?

    Science.gov (United States)

    Nimmagadda, Satya Sudhish; Mahabala, Chakrapani; Boloor, Archith; Raghuram, Pavan Manibettu; Nayak U., Akshatha

    2014-01-01

    Background and Objectives: Dengue fever (DF) is transmitted by Aedes aegypti mosquitoes. With growing population, rapid urbanization and lack of appropriate sanitary measures, proliferation of mosquitoes and subsequent dengue infections have increased rampantly with an estimated 30-fold increase in incidence over last five decades. With rising disease burden, atypical manifestations have increased as well, which are missed most often due to lack of awareness. Our aim was to look for the atypical manifestations of dengue fever. Materials and Methods: A prospective hospital based observational study was conducted at hospitals of Kasturba Medical College in Mangalore over a period of two years (June–2010 to May–2012). One-hundred fifty ELISA confirmed IgM-dengue sero-positive cases satisfying WHO criteria were examined clinically and laboratory data assessed till they got discharged from hospital after ruling out other causes of fever. Atypical manifestations in dengue fever were noted and analyzed. Results: Most common symptoms noticed were myalgia, headache, rash, arthralgia, pain in abdomen and nausea. More than half of the study group had one or the other atypical manifestation. Liver function test derangement was most often seen. Most common atypical manifestation was hepatitis found in 40.6% patients. Febrile diarrhea, renal failure, Acalculous cholecystitis and conduction abnormalities of heart were among other common manifestations. Three patients died of multi-organ dysfunction, disseminated intravascular coagulation and shock. Platelet count did not correlate well with severity of bleeding. Overall recovery rate was good. Conclusion: Some of the atypical manifestations of dengue fever are no more a rare entity. Clinical vigilance for these manifestations is important for timely detection and management as some of them could be fatal. PMID:24596727

  2. Atypical Manifestations of Dengue Fever (DF) - Where Do We Stand Today?

    Science.gov (United States)

    Nimmagadda, Satya Sudhish; Mahabala, Chakrapani; Boloor, Archith; Raghuram, Pavan Manibettu; Nayak U, Akshatha

    2014-01-01

    Dengue fever (DF) is transmitted by Aedes aegypti mosquitoes. With growing population, rapid urbanization and lack of appropriate sanitary measures, proliferation of mosquitoes and subsequent dengue infections have increased rampantly with an estimated 30-fold increase in incidence over last five decades. With rising disease burden, atypical manifestations have increased as well, which are missed most often due to lack of awareness. Our aim was to look for the atypical manifestations of dengue fever. A prospective hospital based observational study was conducted at hospitals of Kasturba Medical College in Mangalore over a period of two years (June-2010 to May-2012). One-hundred fifty ELISA confirmed IgM-dengue sero-positive cases satisfying WHO criteria were examined clinically and laboratory data assessed till they got discharged from hospital after ruling out other causes of fever. Atypical manifestations in dengue fever were noted and analyzed. Most common symptoms noticed were myalgia, headache, rash, arthralgia, pain in abdomen and nausea. More than half of the study group had one or the other atypical manifestation. Liver function test derangement was most often seen. Most common atypical manifestation was hepatitis found in 40.6% patients. Febrile diarrhea, renal failure, Acalculous cholecystitis and conduction abnormalities of heart were among other common manifestations. Three patients died of multi-organ dysfunction, disseminated intravascular coagulation and shock. Platelet count did not correlate well with severity of bleeding. Overall recovery rate was good. Some of the atypical manifestations of dengue fever are no more a rare entity. Clinical vigilance for these manifestations is important for timely detection and management as some of them could be fatal.

  3. Evaluation of dengue fever reports during an epidemic, Colombia.

    Science.gov (United States)

    Romero-Vega, Liliana; Pacheco, Oscar; de la Hoz-Restrepo, Fernando; Díaz-Quijano, Fredi Alexander

    2014-12-01

    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.

  4. Evaluation of dengue fever reports during an epidemic, Colombia

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    Liliana Romero-Vega

    2014-12-01

    Full Text Available 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.

  5. STUDY OF ULTRASOUND FINDING IN DENGUE FEVER

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    Sunita Bajaj

    2016-10-01

    Full Text Available BACKGROUND Dengue fever (DF is a viral haemorrhagic fever causing severe morbidity and mortality in affected patients. The aim of the study is to describe the role of ultrasonography (USG in the assessment of patients with Dengue fever, and its complications and to prove ultrasound is useful in the diagnosis during an epidemic. MATERIALS AND METHODS It is a prospective study was conducted in 2016 comprising of 178 patients who were serologically positive for dengue, radiological investigations were conducted in all cases. RESULTS Out of 178 patients Males (N=117 are more effected subjects in the study. female: Male ratio is 1:2. Hepatomegaly 74.1% which is most common findings in study, 113 (63.4% had GB wall thickening 98 had ascites (55%, 32 had pleural effusion (17.9%. most commonly seen in the age group of 20-39 years. Hepatomegaly was the most common finding noted in 67 patients (37.6%, followed by GB wall thickening in 65 patients (36.1%. Hepatomegaly was more common in 0-19 is 56 patients with 31.4% years age group Ascites in >40 years age group (16.8%. Hepatomegaly was seen in most of the patients whose platelet count was <40,000. (94.7%. GB wall thickening (88.5% common findings seen in patients whose platelet count was <40,000. In patients with platelet count of 40,000-80,000, Ascites is most common finding (87.5%, followed by Splenomegaly (60.7%. In patients whose platelet count was 80,000-150,000, Ascites (50% was more common than Splenomegaly (45.8%. In three patients with platelet count more than 150,000, no sonological abnormality was detected. CONCLUSIONS Ultrasound findings of hepatic changes, GB wall oedema, splenomegaly, ascites and pleural effusion in patients presenting with signs and symptoms of Dengue fever during an epidemic are diagnostic. Contributing in the differential diagnosis with other causes of febrile disease.

  6. Climate change and the emergence of vector-borne diseases in Europe: case study of dengue fever.

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    Bouzid, Maha; Colón-González, Felipe J; Lung, Tobias; Lake, Iain R; Hunter, Paul R

    2014-08-22

    Dengue fever is the most prevalent mosquito-borne viral disease worldwide. Dengue transmission is critically dependent on climatic factors and there is much concern as to whether climate change would spread the disease to areas currently unaffected. The occurrence of autochthonous infections in Croatia and France in 2010 has raised concerns about a potential re-emergence of dengue in Europe. The objective of this study is to estimate dengue risk in Europe under climate change scenarios. We used a Generalized Additive Model (GAM) to estimate dengue fever risk as a function of climatic variables (maximum temperature, minimum temperature, precipitation, humidity) and socioeconomic factors (population density, urbanisation, GDP per capita and population size), under contemporary conditions (1985-2007) in Mexico. We then used our model estimates to project dengue incidence under baseline conditions (1961-1990) and three climate change scenarios: short-term 2011-2040, medium-term 2041-2070 and long-term 2071-2100 across Europe. The model was used to calculate average number of yearly dengue cases at a spatial resolution of 10 × 10 km grid covering all land surface of the currently 27 EU member states. To our knowledge, this is the first attempt to model dengue fever risk in Europe in terms of disease occurrence rather than mosquito presence. The results were presented using Geographical Information System (GIS) and allowed identification of areas at high risk. Dengue fever hot spots were clustered around the coastal areas of the Mediterranean and Adriatic seas and the Po Valley in northern Italy. This risk assessment study is likely to be a valuable tool assisting effective and targeted adaptation responses to reduce the likely increased burden of dengue fever in a warmer world.

  7. Dengue-1 Virus Isolation during First Dengue Fever Outbreak on Easter Island, Chile

    Science.gov (United States)

    Abarca, Katia; Ovalle, Jimena; Ferrer, Pablo; Godoy, Paula; Olea, Andrea; Aguilera, Ximena; Ferrés, Marcela

    2003-01-01

    Dengue virus was detected for the first time in Chile, in an outbreak of dengue fever on Easter Island. The virus was isolated in tissue culture and characterized by reverse transcription–polymerase chain reaction as being dengue type 1. PMID:14718094

  8. Dengue fever among Israeli expatriates in Delhi, 2015: implications for dengue incidence in Delhi, India.

    Science.gov (United States)

    Neuberger, Ami; Turgeman, Avigail; Lustig, Yaniv; Schwartz, Eli

    2016-03-01

    We present the data of 13 dengue cases diagnosed between 1 August and 15 September 2015 among 240 Israeli expatriates residing in Delhi. Attack rates were similar between adults (6/128, 4.7%) and children (7/112, 6.3%). dengue virus (DENV-2) was identified in two and DENV-1 in one dengue-seropositive sample. Another febrile patient was diagnosed with chikungunya virus infection. The reported incidence of dengue fever among people living in Delhi was lower than 0.1% as of September 2015. Based on our results, we hypothesize that the incidence of dengue fever in Delhi is grossly underestimated.

  9. Cavity Forming Pneumonia Due to Staphylococcus aureus Following Dengue Fever.

    Science.gov (United States)

    Miyata, Nobuyuki; Yoshimura, Yukihiro; Tachikawa, Natsuo; Amano, Yuichiro; Sakamoto, Yohei; Kosuge, Youko

    2015-11-01

    While visiting Malaysia, a 22-year-old previously healthy Japanese man developed myalgia, headache, and fever, leading to a diagnosis of classical dengue fever. After improvement and returning to Japan after a five day hospitalization, he developed productive cough several days after defervescing from dengue. Computed tomography (CT) thorax scan showed multiple lung cavities. A sputum smear revealed leukocytes with phagocytized gram-positive cocci in clusters, and grew an isolate Staphylococcus aureus sensitive to semi-synthetic penicillin; he was treated successfully with ceftriaxone and cephalexin. This second reported case of pneumonia due to S. aureus occurring after dengue fever, was associated both with nosocomial exposure and might have been associated with dengue-associated immunosuppression. Clinicians should pay systematic attention to bacterial pneumonia following dengue fever to establish whether such a connection is causally associated.

  10. An analysis of a short-lived outbreak of dengue fever in Mauritius.

    Science.gov (United States)

    Ramchurn, S K; Moheeput, K; Goorah, S S

    2009-08-27

    During the month of June 2009, Mauritius experienced a short-lived outbreak of dengue fever localised in its capital city Port Louis. Aedes albopictus, a secondary vector of dengue viruses, was the probable vector. We introduce a method which combines Google Earth images, stochastic cellular automata and scale free network ideas to map this outbreak. The method could complement other techniques to forecast the evolution of potential localised mosquito-borne viral outbreaks in Mauritius and in at-risk locations elsewhere for public health planning purposes.

  11. STUDY OF CLINICAL PROFILE OF DENGUE FEVER WITH SPECIAL REFERENCE TO ACUTE COMPLICATIONS

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    Keshava

    2014-02-01

    Full Text Available ABSTRACT: Dengue is the arthropode borne viral infection transmitted by mosquitoes to humans. AIM: To study the various clinical manifestations and acute complications of dengue fever. METHODS: 100 cases of confirmed dengue infection admitted to KIMS, Bangalore between December 2009 and September 2011 were studied. A detailed clinical history and physical examination was done and baseline investigations were performed. The cases were followed-up daily for the clinical and laboratory parameters and were treated according to WHO guidelines. The data related to each of these cases was collected, compiled and analyzed. RESULTS: of the total 100 cases there were 61 male and 39 female. Age group of 21-30 (41 was most commonly affected Maximum number of patients was seen in the September, October, august, July. Commonest presentation was Fever (100% followed by Headache (78%, Myalgia (70%, Arthralgia (66%, low back ache (60%. On examination patients found to have icterus (22%, bleeding spots (26%, rashes (50%, Splenomegaly (18%, Hepatomegaly (15% and Ascites (9%, pleural effusion (16%, crepitations (7%. Platelet count was not very well correlated with the bleeding tendencies. Incidence of DHF was more with secondary Dengue infection than the primary dengue infection. The frequency of complications was high in the patients with secondary dengue infection than the primary infection. CONCLUSION: In our present study classical dengue fever was most common presentation followed by DHF and DSS. Hypotension, hemorrhagic spots, positive tourniquet test, jaundice, pleural effusion, ascites, neck stiffness are the common findings on examination associated with complicated forms of dengue. Bleeding, shock, hepatitis, polyserositis, meningitis, pneumonia are the complications seen in severe forms. On investigation Deranged liver function test, renal function test, secondary dengue infection, thickened gall bladder wall, hepatosplenomegaly on ultrasound abdomen

  12. Understanding the Impact of Anthropogenic and Environmental Changes on Dengue Fever Cases in Puerto Rico

    Science.gov (United States)

    Akanda, A. S.; Serman, E. A.; Couret, J.; Puggioni, G.; Ginsberg, H. S.

    2016-12-01

    Worldwide, there are an estimated 50-100 million cases of dengue fever each year, roughly 30 times the number of cases as 50 years ago. Dengue was introduced to Puerto Rico (PR) in 1963 and it has experienced epidemic activity ever since. There have been 4 large epidemics since 1990, the most recent in 2010 where almost 27,000 cases were reported. Vaccine development remains in the testing stages, and years away from mass distribution. Effective control thus depends on our understanding of the complex relationships between environmental and anthropogenic factors, mosquito vector ecology, and disease epidemiology. Dengue virus is primarily transmitted by Aedes aegypti mosquitoes, which also carry the Zika virus, and humans in urban environments are their preferred hosts. The purpose of our analysis is to identify trends between anthropogenic and environmental changes and dengue fever cases in PR over the past 15 years. Data on housing and population density, percent impervious surface, and percent tree canopy at the municipality level were procured from the U.S. Census Bureau and the Multi-Resolution Land Characteristics Consortium (MLRC) project, respectively. Land cover data from the National Land Cover Database, created by USGS and NOAA, as well as environmental data from the National Climatic Data Center (NCDC), were also used. Smaller land cover and green space analysis studies have been performed for PR, but this is the first study to consider the island as a whole, and in six distinct regions, with regards to increases in dengue fever cases. The results from this study can be used to understand the effects of urbanization and climate change on vector-borne disease transmission in PR and to project the impact of growing sub-urban and urban areas on dengue cases in coming years. Our results could also be used to assess Dengue and Zika transmission in growing megacites of the world, where urban slums provide a favorable habitat for Ae. aegypti and foster

  13. Dengue fever at the U.S.-Mexico border, 1995-1996.

    Science.gov (United States)

    1996-10-04

    Dengue is a mosquito-transmitted acute disease caused by any of four virus serotypes (DEN-1, DEN-2, DEN-3 and DEN-4) and is characterized by acute manifestations that can include fever, headache, myalgia, arthralgia, rash, nausea, and vomiting. On August 25, 1995, public health authorities in Mexico notified the Texas Department of Health (TDH) of an ongoing outbreak of dengue fever in the state of Tamaulipas, which borders south Texas. Because of the year-round presence of the Aedes aegypti mosquito (a major vector for dengue) in southernmost Texas and the frequent movement of persons across the U.S.-Mexico border, the outbreak in adjacent Tamaulipas suggested an increased potential for imported and autochthonous cases in Texas, as had occurred during 1980 and 1986. In response to the notification from Mexico, TDH intensified surveillance efforts for dengue, resulting in identification of 29 laboratory-diagnosed cases in Texas residents, including seven persons with no history of travel outside the state. This report summarizes results of dengue surveillance in the U.S.-Mexico border area during 1995-1996.

  14. Modeling the Effects of Augmentation Strategies on the Control of Dengue Fever With an Impulsive Differential Equation.

    Science.gov (United States)

    Zhang, Xianghong; Tang, Sanyi; Cheke, Robert A; Zhu, Huaiping

    2016-10-01

    Dengue fever has rapidly become the world's most common vector-borne viral disease. Use of endosymbiotic Wolbachia is an innovative technology to prevent vector mosquitoes from reproducing and so break the cycle of dengue transmission. However, strategies such as population eradication and replacement will only succeed if appropriate augmentations with Wolbachia-infected mosquitoes that take account of a variety of factors are carried out. Here, we describe the spread of Wolbachia in mosquito populations using an impulsive differential system with four state variables, incorporating the effects of cytoplasmic incompatibility and the augmentation of Wolbachia-infected mosquitoes with different sex ratios. We then evaluated (a) how each parameter value contributes to the success of population replacement; (b) how different release quantities of infected mosquitoes with different sex ratios affect the success of population suppression or replacement; and (c) how the success of these two strategies can be realized to block the transmission of dengue fever. Analysis of the system's stability, bifurcations and sensitivity reveals the existence of forward and backward bifurcations, multiple attractors and the contribution of each parameter to the success of the strategies. The results indicate that the initial density of mosquitoes, the quantities of mosquitoes released in augmentations and their sex ratios have impacts on whether or not the strategies of population suppression or replacement can be achieved. Therefore, successful strategies rely on selecting suitable strains of Wolbachia and carefully designing the mosquito augmentation program.

  15. Risk factors for shock in children with dengue fever

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    Sriram Pothapregada

    2015-01-01

    Full Text Available Objectives: To evaluate and analyze the clinical and laboratory parameters that were predictive of the development of shock in children with dengue fever. Subjects and Methods: Retrospective study carried out from August 2012 to July 2014 at a tertiary care hospital in Puducherry. Results: Two hundred and fifty-four children were admitted with dengue fever and among them dengue fever without shock was present in 159 children (62.5% and dengue fever with shock was present in 95 cases (37.4%. Various clinical and laboratory parameters were analyzed using univariate and multivariate logistic regression between the two groups and a P value of 20% with concomitant platelet count 6 years, hepatomegaly, pain in the abdomen, and oliguria were the most common risk factors associated with shock in children with dengue fever. There were six deaths (2.4% and out of them four presented with impaired consciousness (66.6% at the time of admission. Conclusion: Age >6 years, hepatomegaly, abdomen pain, and oliguria were the most common risk factors for shock in children with dengue fever. Impaired consciousness at admission was the most ominous sign for mortality in dengue fever. Hence, these features should be identified early, monitored closely, and managed timely.

  16. Risk factors for shock in children with dengue fever.

    Science.gov (United States)

    Pothapregada, Sriram; Kamalakannan, Banupriya; Thulasingham, Mahalakshmy

    2015-11-01

    To evaluate and analyze the clinical and laboratory parameters that were predictive of the development of shock in children with dengue fever. Retrospective study carried out from August 2012 to July 2014 at a tertiary care hospital in Puducherry. Two hundred and fifty-four children were admitted with dengue fever and among them dengue fever without shock was present in 159 children (62.5%) and dengue fever with shock was present in 95 cases (37.4%). Various clinical and laboratory parameters were analyzed using univariate and multivariate logistic regression between the two groups and a P value of 20% with concomitant platelet count 6 years, hepatomegaly, pain in the abdomen, and oliguria were the most common risk factors associated with shock in children with dengue fever. There were six deaths (2.4%) and out of them four presented with impaired consciousness (66.6%) at the time of admission. Age >6 years, hepatomegaly, abdomen pain, and oliguria were the most common risk factors for shock in children with dengue fever. Impaired consciousness at admission was the most ominous sign for mortality in dengue fever. Hence, these features should be identified early, monitored closely, and managed timely.

  17. Transverse Myelitis as an Unusual Complication of Dengue Fever.

    Science.gov (United States)

    Mota, Mânlio Tasso de Oliveira; Estofolete, Cássia Fernanda; Zini, Nathalia; Terzian, Ana Carolina Bernardes; Gongora, Delzi Vinha Nunes; Maia, Irineu Luiz; Nogueira, Maurício Lacerda

    2017-02-08

    Dengue fever is the most common arbovirus disease, and presents with a large spectrum of clinical manifestations ranging from asymptomatic disease through to the development of dengue hemorrhagic fever. These extreme cases can lead to dengue shock syndrome, and sometimes death. Spinal cord involvement in dengue virus (DENV) infections is rare. Here, we report a case in which the patient developed acute transverse myelitis (TM) without paraparesis following a DENV infection. This case highlights the importance of physicians' awareness of the possible link between DENV and TM in endemic areas.

  18. Dengue Fever Presenting as Purtscher-like Retinopathy.

    Science.gov (United States)

    Lima, Luiz H; Vianello, Silvana; Pimentel, Sérgio; Costa de Andrade, Gabriel; Zett, Claudio; Muller, Léo; Farah, Michel E; Belfort, Rubens

    2017-03-21

    To report the fundus manifestations and spectral-domain optical coherence tomographic (SD-OCT) features of dengue fever presenting as Purtscher-like retinopathy. Retrospective review of two cases of dengue fever. Color fundus photograph revealed the presence of cotton-wool spots in a Purtscher-like configuration in the posterior pole of all study eyes. SD-OCT demonstrated increased reflectivity signal in the inner retinal layers, and after a variable follow-up period, there was complete disappearance of cotton-wool spots and persistence of the hyperreflectivity signal. We report two unique cases of dengue fever associated with retinal lesions in a configuration of Purtscher-like retinopathy.

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

    Science.gov (United States)

    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

  20. Dengue fever presenting with acute cerebellitis: a case report.

    Science.gov (United States)

    Withana, Milinda; Rodrigo, Chaturaka; Chang, Thashi; Karunanayake, Panduka; Rajapakse, Senaka

    2014-03-05

    The incidence of dengue fever is on the rise in tropical countries. In Sri Lanka, nearly 45,000 patients were reported in 2012. With the increasing numbers, rare manifestations of dengue are occasionally encountered. We report a patient who presented with bilateral cerebellar signs as the presenting feature of dengue. A 45-year-old previously healthy female from the suburbs of Colombo, Sri Lanka presented with an acute febrile illness associated with unsteadiness of gait. Clinical examination revealed a scanning dysarthria and marked horizontal nystagmus with bilateral dysmetria, dysdiadokokinesia and incordination more prominent on the right. Her gait was wide-based and ataxic with a tendency to fall to the right more than to the left. Dengue nonstructural protein antigen 1 test and IgM antibody testing both became positive indicating acute dengue infection. She recovered from the febrile episode within 9 days since the onset of fever but cerebellar symptoms outlasted the fever by one week. The magnetic resonance imaging of brain was normal and cerebellar signs resolved spontaneously by day 17 of the illness. Cerebellar syndrome in association with dengue fever has been reported in only four instances and our patient is the first reported case of dengue fever presenting with cerebellitis as the first manifestation of disease. This case report is intended to highlight the occurrence of acute cerebellitis as a presenting syndrome of the expanding list of unusual neurological manifestations of dengue infection.

  1. Guillain-Barre syndrome following dengue fever and literature review.

    Science.gov (United States)

    Ralapanawa, Dissanayake Mudiyanselage Priyantha Udaya Kumara; Kularatne, Senanayake Abeysinghe Mudiyanselage; Jayalath, Widana Arachilage Thilak Ananda

    2015-11-27

    Dengue is an arboviral infection that classically presents with fever, joint pain, headaches, skin flush and morbilliform rashes. The incidence of neurological symptoms and complications in dengue varies from 1 to 25% that include encephalopathy, Guillain-Barre syndrome (GBS), acute motor weakness, seizures, neuritis, hypokalaemic paralysis, pyramidal tract signs, and a few more. Dengue fever as an antecedent infection in GBS is uncommon. A 34-years-old Sri Lankan Sinhalese male presented with fever, headache and myalgia of 3 days and developed leucopenia and thrombocytopenia without evidence of haemoconcentration. The diagnosis of dengue fever was confirmed as he had positive dengue NS1 antigen test on the third day of fever. He made full recovery and was discharged after 4 days of hospital stay. Six days later, he presented with history of acute flaccid weakness of both lower limbs and upper limbs which was of progressive ascending nature. The electromyography had evidence of demyelinating neuropathy and cerebrospinal fluid showed albuminocytological dissociation. Subsequently, IgM for dengue virus was positive. Dengue is endemic in Sri Lanka. Post dengue Guillain-Barre syndrome is a potential neurological complications of this infection.

  2. High level of awareness but poor practices regarding dengue fever control: A cross-sectional study from North India

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    Palanivel Chinnakali

    2012-01-01

    Full Text Available Background: Delhi, the capital of India, has suffered many outbreaks of dengue in recent past and despite the obvious magnitude of problem, very scarce evidence exists that documents the knowledge, awareness and practices of the people regarding dengue. Aim: To assess the knowledge and practices related to control of dengue fever and to assess the differences in knowledge and practices based on sex and literacy. Materials and Methods: A cross-sectional study was conducted among persons visiting a tertiary care hospital in New Delhi. A systematic sampling procedure was adopted and a pretested questionnaire was used. Results: A total of 215 individuals were interviewed. Majority of the respondents (96.3% had heard about dengue. The important sources of information were television (54.9% and newspaper/magazines (51.7%. Around 89% of the study participants considered dengue as "serious problem." Nearly 86% participants were aware of the spread of dengue by mosquitoes while 73% were aware of one of the correct breeding sites of Aedes mosquito. Mosquito mats/liquidators were used by 61% of respondents, coils by 56% and repellant creams by 22%. Conclusion: The awareness regarding dengue and mosquito control measures was satisfactory to an extent. Programs should focus that this knowledge gets translated into practice.

  3. [Dengue fever cases in Czech workers returning from the Maldives].

    Science.gov (United States)

    Trojánek, Milan; Tomíčková, Dora; Roháčová, Hana; Kosina, Pavel; Gebouský, Jan; Dvořák, Jan; Chmelik, Vaclav; Batistová, Květoslava; Husa, Petr; Maixner, Jan; Sojková, Naděžda; Zelená, Hana; Marešová, Vilma; Stejskal, František

    2013-09-01

    The objective of this study is to present epidemiological characteristics and clinical symptoms of dengue fever cases in Czech workers who acquired the infection while working on the island of Fushivelavaru, Maldives. Furthermore, the study compares the sensitivity of novel direct detection assays, i.e. Real-Time Polymerase Chain Reaction (RT-PCR) and detection of Dengue NS1 antigen. The retrospective study evaluated the clinical course of dengue fever cases in Czech workers returning from a job in the Maldives who were diagnosed with dengue virus infection from September 1 to October 31, 2012. The laboratory diagnosis of dengue fever was based on the serological detection of IgM and IgG antibodies, detection of dengue NS1 antigen by enzyme-linked immunosobent assay (ELISA), and detection of dengue virus DNA by RT-PCR. The infection with dengue virus was confirmed in 18 males with a median age of 40 years (IQR 36-47) who returned from a job in the Maldives. Only one patient required admission to the hospital while the others were treated on an outpatient basis. The most frequently observed symptoms were fever (18), headache (9), muscle and joint pain (8 and 7, respectively), and rash (9). Typical laboratory findings were leukocytopenia and thrombocytopenia, a low CRP level, and elevated aminotransferase activity. The clinical course was uncomplicated in all patients. The dengue NS1 antigen detection (positive in all 10 patients with acute dengue fever) showed significantly higher sensitivity than the detection of viral RNA using RT-PCR (positive in 4 patients), p = 0.011. Although the vast majority of dengue fever cases are diagnosed among travellers returning from the tropics, the presented study points out the risks posed by dengue fever to long-term workers in endemic areas. The infection in the serologically naïve hosts is usually uncomplicated; however, infected persons are at significant risk of developing a severe complicated clinical course if challenged

  4. An optimal control strategies using vaccination and fogging in dengue fever transmission model

    Science.gov (United States)

    Fitria, Irma; Winarni, Pancahayani, Sigit; Subchan

    2017-08-01

    This paper discussed regarding a model and an optimal control problem of dengue fever transmission. We classified the model as human and vector (mosquito) population classes. For the human population, there are three subclasses, such as susceptible, infected, and resistant classes. Then, for the vector population, we divided it into wiggler, susceptible, and infected vector classes. Thus, the model consists of six dynamic equations. To minimize the number of dengue fever cases, we designed two optimal control variables in the model, the giving of fogging and vaccination. The objective function of this optimal control problem is to minimize the number of infected human population, the number of vector, and the cost of the controlling efforts. By giving the fogging optimally, the number of vector can be minimized. In this case, we considered the giving of vaccination as a control variable because it is one of the efforts that are being developed to reduce the spreading of dengue fever. We used Pontryagin Minimum Principle to solve the optimal control problem. Furthermore, the numerical simulation results are given to show the effect of the optimal control strategies in order to minimize the epidemic of dengue fever.

  5. NNDSS - Table II. Cryptosporidiosis to Dengue Hemorrhagic Fever

    Data.gov (United States)

    U.S. Department of Health & Human Services — NNDSS - Table II. Cryptosporidiosis to Dengue Hemorrhagic Fever - 2014. In this Table, all conditions with a 5-year average annual national total of more than or...

  6. Fluid therapy monitoring for dengue haemorrhagic fever and other pathologies

    OpenAIRE

    Josà Rubens Costa Lima

    2014-01-01

    Dengue patients that were prematurely hydrated to prevent a dengue hemorrhagic fever (DHF) shock were investigated. These patients had complications and died in strong clinical and epidemiological association with progressive anemias, not caused by hemorrhages, and without presenting laboratorial proof of the specific natural sign of DHF, the hemoconcentration. It was demonstrated that the association between dengue and anemias in Fortaleza is not natural. Further investigation of admitted pa...

  7. A Patient with Dengue Fever Presenting with Rhabdomyolysis.

    Science.gov (United States)

    Nakamura, Masayuki; Ikeda, Shuntaro; Nagahara, Hiroyuki; Hitsumoto, Tatsurou; Matsui, Shogo; Kadota, Hisaki; Shimizu, Hideaki; Ohshima, Kiyotaka; Yakushiji, Naoki; Hamada, Mareomi

    2015-01-01

    A 16-year-old boy stayed in Tokyo near Yoyogi Park for extracurricular high school activities. After returning home, he experienced an episode of fever and visited our emergency outpatient unit. He initially exhibited symptoms of leukopenia, thrombocytopenia and concomitant rhabdomyolysis and after admission simultaneously developed a biphasic fever and systemic erythema. Based on the results of reverse transcription polymerase chain reaction testing, he was finally diagnosed with dengue fever. After an absence of 70 years, dengue fever has reemerged as a domestic infection. Awareness of this trend led to our diagnosis.

  8. Community Participation, Dengue Fever Prevention and Control Practices in Swat, Pakistan.

    Science.gov (United States)

    Zahir, Abdul; Ullah, Asad; Shah, Mussawar; Mussawar, Arsalan

    2016-01-01

    The aim of this study was to determine the role of community participation in prevention of dengue fever in The Swat district located in the Northern area of Khyber Pakhtunkhwa, Pakistan, which experienced a dengue fever outbreak in August, 2013. A total number of 8,963 dengue cases with 0.4% case fatality ratio were registered during the outbreak. A sample size of 354 respondents were proportionally allocated to each residential colony and then randomly selected. The association of independent variable (Community participation) and dependent variable (practices for control) were tested by using Chi Square test. Results regarding perception of practices for dengue control with community participation showed that: practices for control had significant association with organization of people to eradicate dengue mosquitoes (p=0.00), community leaders (p=0.04), community efforts (p≤0.01), use of insecticides by community people (p=0.00) and involvement of community people in awareness campaign (p=0.00). Similarly, significant associations were found between practices for control and community shared information during dengue outbreak (p=0.00), community link with health department, NGO, Other agencies (p=0.02). We conclude that the spread of dengue epidemic was aided by the ignorance, laziness of the community people and government agencies. However, the people, religious scholars, leaders and government agencies were not organized to participate in dengue prevention and eradication, hence, the chances of dengue infection increased in community. The study recommends mobilizing local communities and activating local leadership with active participation of Government and non-government organizations for initiation of preventive strategies.

  9. STUDY OF SERUM AMINOTRANSFERASE LEVELS IN DENGUE FEVER

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    Jnaneshwari

    2014-03-01

    Full Text Available BACKGROUND: The involvement of liver in dengue fever is not uncommon as reported in literature since 1970. Liver and nervous system involvement simultaneously predicts poor outcome in dengue fever. Atypical manifestations include liver involvement with elevation of enzymes, central nervous involvement (encephalopathy and cardiac alterations (myocarditis. Liver involvement in dengue fever is manifested by the elevation of transaminases representing reactive hepatitis, due to direct attack of virus itself or the use of hepatotoxic drugs. OBJECTIVE OF THE STUDY: Study of serum aminotransferase levels in dengue fever. METHODOLOGY: In this descriptive, cross sectional study, all patients who presented to the Department of medicine with dengue IgM positive were included. Study period of 24 months from July 2010-June 2012, patients attending to M.S. Ramaiah medical college were included (n=166. RESULTS: 166 patients reactive for dengue virus specific IgM antibody were studied. As per WHO classification, 137 (82.5% patients were classified as dengue fever, 20 (12% as dengue hemorrhagic fever, and 9 (5.4% as dengue shock syndrome. Mean age of dengue infection patients was 35.71 ±12.9 (SD years, with male to female ratio nearly equal. Hepatic dysfunction is very common in all forms of dengue infection, with AST rising significantly more than ALT. Serum aminotransferase levels appear to have a directly proportional correlation with grading of dengue infection. Hyperbilirubinemia, elevated transaminases, hypoproteinemia, hypoalbuminemia and deranged coagulation profile were seen in higher frequency in DHF and DSS group as compared to classical DF group. AST and ALT were significantly higher in patients with secondary infection (IgM & IgG positive as compared to primary infection (IgM positive. CONCLUSION: Serum aminotransferase levels are significantly raised in all forms of dengue infection and it directly correlates with severity of infection. Serum

  10. Meteorological factors and dengue fever transmission in South Taiwan

    Science.gov (United States)

    Chien, Lung-Chang; Lin, Yuan-Chien; Cheng, Ming-Hung; Yu, Hwa-Lung

    2013-04-01

    The variations in meteorological conditions induced by climate change causes the diffusion pattern of infectious disease and serious epidemic situation. The objective of this study is to investigate the impact of meteorological variables to the temporal variation of dengue fever epidemic in weekly basis in south Taiwan. Several extreme and average index of meteorological variables, i.e. temperature and humidity, were used for this analysis, including averaged, maximum and minimum temperature, and average rainfall, maximum 1-hr rainfall, and maximum 24-hr rainfall. This study applies the distributed lag nonlinear model (DLNM) to reveal the significant meteorological variables and their temporal lag effects to the dengue fever epidemic by analyzing the dengue fever records from 1998-2011. Results show that the weekly minimum temperature (minT) and 1-hr maximum rainfall (maxR) are significantly important to the dengue fever spread. Among them, once minT is higher than 20°C, the relative risk of dengue fever of nine-fourteen week later will be significantly elevated. On the other hand, the incidences of maxR higher than 80mm can also increase the relative risk of dengue fever occurrences around nine-fourteen weeks afterwards.

  11. Response of the mosquito protein interaction network to dengue infection

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    Pike Andrew D

    2010-06-01

    Full Text Available Abstract Background Two fifths of the world's population is at risk from dengue. The absence of effective drugs and vaccines leaves vector control as the primary intervention tool. Understanding dengue virus (DENV host interactions is essential for the development of novel control strategies. The availability of genome sequences for both human and mosquito host greatly facilitates genome-wide studies of DENV-host interactions. Results We developed the first draft of the mosquito protein interaction network using a computational approach. The weighted network includes 4,214 Aedes aegypti proteins with 10,209 interactions, among which 3,500 proteins are connected into an interconnected scale-free network. We demonstrated the application of this network for the further annotation of mosquito proteins and dissection of pathway crosstalk. Using three datasets based on physical interaction assays, genome-wide RNA interference (RNAi screens and microarray assays, we identified 714 putative DENV-associated mosquito proteins. An integrated analysis of these proteins in the network highlighted four regions consisting of highly interconnected proteins with closely related functions in each of replication/transcription/translation (RTT, immunity, transport and metabolism. Putative DENV-associated proteins were further selected for validation by RNAi-mediated gene silencing, and dengue viral titer in mosquito midguts was significantly reduced for five out of ten (50.0% randomly selected genes. Conclusions Our results indicate the presence of common host requirements for DENV in mosquitoes and humans. We discuss the significance of our findings for pharmacological intervention and genetic modification of mosquitoes for blocking dengue transmission.

  12. A Delay Differential Equation Model for Dengue Fever Transmission in Selected Countries of South-East Asia

    Science.gov (United States)

    Sakdanupaph, Werapong; Moore, Elvin J.

    2009-08-01

    Dengue Fever is a dangerous viral disease that is transmitted by female Aedes mosquitoes and is common in more than 100 countries in the world and in all countries of South-East Asia. Mathematical models of Dengue Fever transmission are useful for studying the causes of the spread of the disease and to try to develop methods for reducing the spread of the disease. In this paper, a mathematical model for Dengue fever is analyzed consisting of a system of four nonlinear differential equations with two time delays. The model includes infected humans, infectious humans, infected mosquitoes and infectious mosquitoes. The model has disease-free and endemic equilibrium points. The asymptotic stability of the equilibrium points are studied analytically. The Matlab computer program is used to obtain numerical solutions of the model for both zero and nonzero time delays for a range of parameter values. It is found that for some reasonable estimates of parameter values the endemic equilibrium point is asymptotically stable, but the approach to equilibrium is very slow, suggesting that this equilibrium point may not be of practical importance for these parameter values. Some comparisons are made between the model results and the actual data for Dengue Fever in Thailand, Malaysia and Singapore.

  13. Analysis of Impact of Geographical Environment and Socio-economic Factors on the Spatial Distribution of Kaohsiung Dengue Fever Epidemic

    Science.gov (United States)

    Hsu, Wei-Yin; Wen, Tzai-Hung; Yu, Hwa-Lung

    2013-04-01

    Taiwan is located in subtropical and tropical regions with high temperature and high humidity in the summer. This kind of climatic condition is the hotbed for the propagation and spread of the dengue vector mosquito. Kaohsiung City has been the worst dengue fever epidemic city in Taiwan. During the study period, from January 1998 to December 2011, Taiwan CDC recorded 7071 locally dengue epidemic cases in Kaohsiung City, and the number of imported case is 118. Our research uses Quantile Regression, a spatial infection disease distribution, to analyze the correlation between dengue epidemic and geographic environmental factors and human society factors in Kaohsiung. According to our experiment statistics, agriculture and natural forest have a positive relation to dengue fever(5.5~34.39 and 3.91~15.52). The epidemic will rise when the ratio for agriculture and natural forest increases. Residential ratio has a negative relation for quantile 0.1 to 0.4(-0.005~-0.78), and a positive relation for quantile 0.5 to0.9(0.01~18.0) . The mean income is also a significant factor in social economy field, and it has a negative relation to dengue fever(-0.01~-0.04). Conclusion from our research is that the main factor affecting the degree of dengue fever in predilection area is the residential proportion and the ratio of agriculture and natural forest plays an important role affecting the degree of dengue fever in non predilection area. Moreover, the serious epidemic area located by regression model is the same as the actual condition in Kaohsiung. This model can be used to predict the serious epidemic area of dengue fever and provide some references for the Health Agencies

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

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    Kuan Mei-Mei

    2012-08-01

    Full Text Available Abstract 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 2X(t-1:Y = 0.22, R2X(t-2:Y = 0.31, P  Conclusions A moderate sensitivity of detecting 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.

  15. Clinical Profile of Atypical Manifestations of Dengue Fever.

    Science.gov (United States)

    Pothapregada, Sriram; Kamalakannan, Banupriya; Thulasingam, Mahalakshmy

    2016-06-01

    To study the clinical profile and outcome of the atypical manifestations of dengue fever in children. All children (0-12 y of age) diagnosed and confirmed as dengue fever at a tertiary care hospital at Puducherry, between the 1st of August 2012 and January 31st 2015 were reviewed retrospectively from hospital case records as per the revised World Health Organization (WHO) guidelines 2011 for dengue fever. The diagnosis was confirmed by NS1 antigen-based ELISA test or dengue serology for IgM and IgG antibodies and the data was analyzed using SPSS 16.0 statistical software. Out of 254 children admitted with dengue fever, non-severe dengue and severe dengue were seen in 62.6 % and 37.4 % respectively. Atypical manifestations were seen in 106 cases (41.7 %). Mean age of presentation was 6.9(3.3) y. M: F ratio was 1.2:1. The common manifestations of severe dengue infection were shock (37.4 %), bleeding (20.1 %) and multi-organ dysfunction (2.4 %). The most common atypical manifestations of dengue fever were lymphadenopathy (41.7 %), splenomegaly (21.2 %), biphasic fever (18.1 %), hepatitis (11.4 %), febrile diarrhea (6.3 %), refractory shock (2.4 %) and impaired consciousness (1.9 %). The other atypical manifestations present were portal hypertension, acalculous cholecystitis, appendicitis, acute respiratory distress syndrome (ARDS), myocarditis, pericardial effusion, paroxysmal supraventricular tachycardia (PSVT), myositis, acute kidney injury (AKI), hemophagocytic syndrome and disseminated intravascular coagulopathy (DIC). Platelet count did not always correlate well with the severity of bleeding. There were six deaths (2.4 %) and out of them four presented with impaired consciousness (66.6 %). The common causes for poor outcome were multiorgan failure, encephalopathy and refractory shock. The atypical manifestations of dengue fever are no more a rare entity. Clinicians should have a high index of suspicion and vigilance for atypical manifestations of

  16. Awareness of dengue fever among school children: a comparison between private and government schools

    Directory of Open Access Journals (Sweden)

    Shivani Kalra

    2014-12-01

    Full Text Available Background: Dengue is the mosquito born viral disease spreading its tentacles all over the world. Dengue constitutes for major cause of deaths in children. According to WHO, globally it was estimated that approximately 70-100 million people were infected every year. Therefore, the study has been conducted with the aim to assess knowledge regarding dengue fever among school children. Methodology: Total of 500 children were selected from 9th and 10th class of private and government schools using total enumerative sampling technique. Data was collected using questionnaire method. After assessing knowledge classes were taken by investigators focusing on prevention of dengue fever. Results: Finding of study revealed that among Private schools excellent knowledge was found in 06 (01.2% children, good in 123 (24.6% children, average 112 (22.4% children and poor in 02 (00.41 whereas in Government schools none of students had excellent knowledge, 76(15.2% children were having good knowledge, 178(35.6% children were having average knowledge & 03 (00.6 children were having poor knowledge. The mean knowledge scores were higher in students of Private schools i.e. 31.45 ± 6.41 as compared to students of Government schools i.e. 28.17 ± 5.39 at t=6.19 (p=0.00. Conclusion: It is concluded that majority of school students of private and government schools were having average knowledge regarding prevention of dengue fever. Therefore, there is need for further information, education and communication programs regarding prevention of dengue fever and this can be achieved by organizing health education campaigns in community involving schools.

  17. CLINICAL PROFILE OF DENGUE FEVER IN KANYAKUMARI GOVERNMENT MEDICAL COLLEGE- A STUDY FROM KANYAKUMARI, INDIA

    Directory of Open Access Journals (Sweden)

    Brinda J

    2017-01-01

    -severe dengue, which included both undifferentiated fever and Dengue Fever (DF (both with and without warning signs and 12 (30% were cases of severe dengue (DHF grades 1-4. The maximum numbers of cases were seen in the group 25-34 years of age (32.5% followed by 15-24 years (27.5%, 35-44 years (25% and 45-55 years (15%. There was significant difference in male:female ratio in our study (2.3:1. Covered dress used by females may be a cause for the fewer incidences. 2 Increased admissions in the rainy and winter seasons can be explained by breeding season of mosquitoes, which is similar to previous studies. Duration of hospitalisation was more in case of severe dengue patients. 3 Various factors apart from thrombocytopenia lead to bleeding in dengue. They are decreased platelet function, fibrinogen consumption, prolongation of PT/PTT and vasculopathy. In our study, in the majority of the patients, tourniquet test was found to be negative, whereas studies in other countries, especially Southeast Asian countries, report tourniquet test positivity as the commonest bleeding manifestation. 4 Low proportion of positive tourniquet test in Indian studies maybe due to the darker skin colour in Indians. The most consistent finding was hepatomegaly, which was similar to many other studies. 5 Among the various clinical findings, hypotension, pleural effusion and respiratory distress were notable and were analogous to other studies. 6 In our study, thrombocytopenia was seen in 37 (97.5% of cases. Evidence of haemoconcentration is not seen in our study group. In some DF patients, the rise of PCV could have been due to dehydration as a result of poor intake and vomiting. This differs from the pattern seen in viral hepatitis. Rise in PT/ aPTT also depicts severity of disease. Ascites was the most common presentations. USG of abdomen revealed ascites in 10 (37% of cases.

  18. Scanning electron microscopy of the four larval instars of the Dengue fever vector Aedes aegypti (Diptera: Culicidae).

    Science.gov (United States)

    Schaper, Stefan; Hernández-Chavarría, Francisco

    2006-09-01

    Aedes aegypti is the main insect vector of Dengue fever and dengue hemorrhagic fever/dengue shock syndrome and represents the only vulnerable element in the control of this disease. Therefore, the identification and quantification of this mosquito is an important task; however, the majority of taxonomic keys are based on the 4th larval instar. For that reason, this study describes the four larval instars ofA. aegypti using scanning electron microscopy. Morphological changes during larval development were observed at the pecten, comb scales and the ventral brush of the abdominal segment X; however, the 3rd and 4th instars showed similar structures with only a slight variation. The structures described in this study will be helpful in the identification of the four instars of A. aegypti, a fundamental task for comprehending the natural history of dengue mainly in new territories affected.

  19. Is transfusion-transmitted dengue fever a potential public health threat?

    Science.gov (United States)

    Pozzetto, Bruno; Memmi, Meriam; Garraud, Olivier

    2015-05-12

    Dengue is an arboviruses due to single-stranded enveloped ribonucleic acid viruses, named dengue viruses (DENV), that include four serotypes and are mainly transmitted via the bite of mosquitoes of the genus Aedes (A. aegypti and A. albopictus). The distribution of the disease was historically limited to intertropical areas; however, during the last thirty years, the perimeter of the disease extended considerably and temperate areas are now at risk of outbreaks. The present global burden of dengue is considerable: 2.5 billion people over more than 100 countries are concerned; 50 to 100 million infections occur every year, with a number of fatal cases of approximately 20000. Although frequently asymptomatic or limited to a mild fever, dengue is responsible for severe cases mainly consecutive to the occurrence of hemorrhagic complications that can lead to shock and death, notably in children from poor-resource settings. The place of DENV as a transfusion-transmitted pathogen has been recognized only in 2008. At the present time, only five cases of transfusion-transmitted dengue, including one case of dengue hemorrhagic fever, have been formerly documented. This review provides a general overview of dengue, its viruses and their vectors. It replaces the disease in the context of other viral diseases transmitted by arthropods. It discusses the threat of dengue on the supply of blood products in endemic and non endemic areas. Finally, it describes the specific and non specific measures available for improving the security of blood products with regards to this emerging risk. Interestingly, in 2009, the American Association of Blood Banks placed DENV in the highest category of emerging infectious agents for their potential impact on transfusion recipient safety for the next years in North America.

  20. Community knowledge, awareness and preventive practices regarding dengue fever in Puducherry - South India.

    Science.gov (United States)

    Jeelani, S; Sabesan, S; Subramanian, S

    2015-06-01

    To ascertain the knowledge, attitudes and practices of adult population in Puducherry, India, regarding Dengue Fever (DF). A cross-sectional survey was carried out to assess the Knowledge, Awareness and Preventive practices (KAP) among a selected community in Puducherry on DF, following a major dengue outbreak in 2012. Between October 2012 & February 2013, an epidemiological survey was conducted among 400 households (HHs) from the most affected areas during dengue outbreak, which came under eight health delivery jurisdictions i.e. Primary Health Centres (PHCs) in Puducherry. Knowledge of dengue and the use of preventive measures were assessed by means of a pre-tested structured questionnaire. Logistic regression analysis was done to examine the association between different levels of education and income status with the knowledge of DF. The DF knowledge map was created based on the results achieved through the questionnaire using Arc GIS 10.2 software. Although about 86% of the participants had heard of dengue, although there was no adequate knowledge on dengue vector breeding habitat as 68% of the respondents thought drains & garbage as breeding places of dengue vectors. Only 25% of participants were aware of clean water as a breeding habitat. Insufficient knowledge of disease symptoms was found, with fever (59%) being the most common symptom. There is a lack of in-depth knowledge on dengue epidemiology in the Puducherry community and observation revealed that more needs to be done by the Government as well as community members to prevent vector mosquito breeding. Copyright © 2015 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

  1. Could peak proteinuria determine whether patient with dengue fever develop dengue hemorrhagic/dengue shock syndrome? - A prospective cohort study

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    Suhail Sufi M

    2011-08-01

    Full Text Available Abstract Background Worldwide there is a need to develop simple effective predictors that can distinguish whether a patient will progress from dengue fever (DF to life threatening dengue hemorrhagic (DHF or dengue shock syndrome (DSS. We explored whether proteinuria could be used as such a marker. Methods We included patients admitted to hospital with suspected dengue fever. Starting at enrollment until discharge, each patient's daily spot urine protein creatinine ratio (UPCR was measured. We classified those with confirmed dengue infection as DF or DHF (including DSS based on WHO criteria. Peak and day of onset of proteinuria was compared between both groups. Results Compared to those with DF, patients with DHF had significantly higher median peak proteinuria levels (0.56 versus 0.08 g/day; p Conclusions Peak UPCR could potentially predict DHF in patients with dengue requiring close monitoring and treatment.

  2. Spontaneous splenic rupture during the recovery phase of dengue fever.

    Science.gov (United States)

    de Silva, W T T; Gunasekera, M

    2015-07-02

    Spontaneous splenic rupture is a rare but known complication of dengue fever. Previously reported cases have occurred early during the course of the disease and most cases have led to a fatal outcome. Here we report a case of spontaneous splenic rupture in a patient with dengue fever, which occurred during the recovery phase of the illness. A 28-year-old Sinhalese, Sri Lankan man presented with a history of fever, myalgia and vomiting of 4 days duration. Investigations revealed a diagnosis of dengue fever with no signs of plasma leakage. He was managed in the ward as per local protocol. During the recovery phase the patient developed severe abdominal distention with circulatory failure. Radiology revealed splenic rupture with massive amounts of abdominal free fluid. The patient was resuscitated and Emergency laparotomy with splenectomy was performed. The outcome was excellent with the patient making a complete recovery. Although splenic rupture is a known complication of dengue fever it may be manifested late in the disease process. A high degree of suspicion should be maintained and patients must be monitored even during the recovery phase of dengue fever. Early diagnosis and intervention can prevent mortality.

  3. Secondary bacteraemia in adult patients with prolonged dengue fever.

    Science.gov (United States)

    Premaratna, R; Dissanayake, D; Silva, F H D S; Dassanayake, M; de Silva, H J

    2015-03-01

    Although dengue management guidelines do not advice on use of antibiotics in dengue shock syndrome, unrecognised bactraemia is likely to contribute to morbidity and mortality. To assess the occurance of secondary bacteraemia in adult patients with prolonged dengue fever. A prospective study was conducted recruiting patients with confirmed acute dengue infection who had prolonged fever (>5 days). Two sets of blood cultures were taken in such patients prior to institution of antibiotic therapy. Demographic, clinical, haematological and biochemical parameters were recorded. Development of ascites and pleural effusions were detected using ultrasonography. Fourty patients (52.5% males) with a mean age of 29.8 years (SD 13.6) were studied. The average duration of fever was 7.9 days (SD 1.8). Ten patients (25%) had bacterial isolates in their blood cultures; Staphylococcus aureus (n=2), coliforms (n=3), pseudomonas (n=1) and 4 had mixed growths. The culture positive group had severe body aches at admission and higher fever, third space fluid accumulation, a significant drop in platelets and a higher CRP. A quarter of dengue patients with prolonged fever had a bacterial isolate. Culture positive patients appeared more ill with body aches and had higher degrees of fever during the latter part of the illness. Increased vascular permeability may predispose to bacterial seepage into blood. Although white cell count is not helpful in detecting bacteraemia, low platelet count and elevation of CRP seem to be helpful.

  4. Primary dengue fever associated with hemophagocytic syndrome: a report of three imported cases, Bordeaux, France.

    Science.gov (United States)

    Ribeiro, Emmanuel; Kassab, Somar; Pistone, Thierry; Receveur, Marie-Catherine; Fialon, Pierre; Malvy, Denis

    2014-01-01

    The dengue virus is responsible for a wide range of symptoms that can be classified into two distinct syndromes: classical dengue fever and severe dengue fever. Among the complicating forms, hemophagocytic syndrome (HPS) has been previously reported in case series of patients with secondary dengue fever outside of endemic settings. Of note, the occurrence of HPS has not yet been included among the criteria for defining severe dengue fever. We herein present three patients with HPS related to confirmed primary dengue virus infection. Clinicians should therefore consider hemophagocytosis as a complication during severe dengue infection in naïve patients.

  5. Laboratory observations on the larvicidal efficacy of three plant species against mosquito vectors of malaria, dengue/dengue hemorrhagic fever (DF/DHF) and lymphatic filariasis in the semi-arid desert.

    Science.gov (United States)

    Bansal, S K; Singh, Karam V; Sharma, Sapna; Sherwani, M R K

    2012-05-01

    Comparative larvicidal efficacy of aqueous and organic solvent extracts from seeds, leaves and flowers of three desert plants viz. Calotropis procera (Aiton), Tephrosia purpurea (L.) Pers. and Prosopis juliflora (Sw.) DC. was evaluated against Anopheles stephensi (Liston), Aedes aegypti (Linnaeus) and Culex quinquefasciatus (Say). For this purpose larvae of all the three mosquito species were reared in the laboratory and studies carried out on late 3rd or early 4th instars using standard WHO technique. Based on concentration mortality data 24 and 48 hr LC50and LC90 values along with their 95% fiducial limits, regression equation, chi-square (chi2)/ heterogeneity of the response were determined by log probit regression analysis. Experiments were carried out with different solvent extracts of seeds of C. procera which revealed that methanol (24 hr LC50: 127.2, 194.8, 361.0) and acetone (229.9, 368.1,193.0 mg l(-1)) extracts were more effective with the three mosquito species, respectively. Petroleum ether extract was effective only on An. stephensi while aqueous extracts were not effective at all with any of the mosquito species (mortality purpurea and leaves of P. juliflora were 74.9, 63.2 and 47.0 and 96.2,128.1 and 118.8 mg l(-1) for the above three mosquito species, respectively. Experiments carried out up to 500 mg l-(1) with leaves (T. purpurea) and seeds (P. juliflora) extracts show only up to 10-30% mortality indicating that active larvicidal principle may be present only in the seeds of Tephrosia and leaves of Prosopis. In general, anophelines were found more susceptible than the culicines to the plant derived derivatives. More studies are being carried outon some other desert plants found in this arid region. The study would be of great importance while formulating vector control strategy based on alternative plant based insecticides in this semi-arid region.

  6. Dengue fever with diffuse cerebral hemorrhages, subdural hematoma and cranial diabetes insipidus.

    Science.gov (United States)

    Jayasinghe, Nayomi Shermila; Thalagala, Eranga; Wattegama, Milanka; Thirumavalavan, Kanapathipillai

    2016-05-10

    Neurological manifestations in dengue fever occur in dengue fever. We postulate that immunological mechanisms may play a role in pathogenesis. However further comprehensive research and studies are needed to understand the pathophysiological mechanisms leading to this complication.

  7. Analysis of dengue fever risk using geostatistics model in bone regency

    Science.gov (United States)

    Amran, Stang, Mallongi, Anwar

    2017-03-01

    This research aim is to analysis of dengue fever risk based on Geostatistics model in Bone Regency. Risk levels of dengue fever are denoted by parameter of Binomial distribution. Effect of temperature, rainfalls, elevation, and larvae abundance are investigated through Geostatistics model. Bayesian hierarchical method is used in estimation process. Using dengue fever data in eleven locations this research shows that temperature and rainfall have significant effect of dengue fever risk in Bone regency.

  8. Dengue fever in the San Juan Bay Estuary: Evaluating the ...

    Science.gov (United States)

    Dengue is transmitted by Aedes aegypti, a species that thrives in cities. Here we ask which elements within the urban environment could be managed to reduce the potential for Dengue occurrence. In particular, we study the potential of wetlands in the SJBE to buffer from vector proliferation. Wetlands provide ecosystem services such as heat and water hazard mitigation, water purification and habitat for a diversity of species, all of which are factors that have been shown to affect Dengue vectors. As such, we hypothesize that within coastal neighborhoods in the SJBE wetlands, ecosystem services lead to lower Dengue occurrence. We test this hypothesis using Dengue data from 2010-2013, which includes the largest epidemic in PR history. Our analytical model includes relevant socio-economic factors and environmental controls that may also affect Dengue dynamics. Results indicated a negative effect of neighborhood mangrove cover and a positive effect of percent flood area on Dengue prevalence. Moreover, heat hazards were positively correlated with dengue prevalence and negatively correlated with neighborhood mangrove cover. Dengue prevalence did not correlate with herbaceous wetlands, or with the ecosystem services of water quality or vertebrate species richness. Mosquito borne diseases are an increasingly important health concern, which pose great challenges for safe and sustainable control and eradication. This reality calls for management approaches that consider m

  9. [An imported dengue Fever case in Turkey and review of the literature].

    Science.gov (United States)

    Uyar, Yavuz; Aktaş, Eray; Yağcı Çağlayık, Dilek; Ergönül, Onder; Yüce, Ayşe

    2013-01-01

    Dengue fever is an acute viral disease that can affect all age groups in tropical and subtropical countries. The predominant vectors are the mosquitoes namely Aedes aegypti and A.albopictus. Although there have been no case reports in Turkey due to DF, there is seroepidemiological evidence indicating the presence of Dengue virus (DENV) in Turkey. In this case report we presented an imported dengue fever case. The patient was 40 years old, previously healthy male, Switzerland citizen. He had immigrated from Dubai to India two weeks ago and after one week from immigration he attended to a hospital in India because of high fever. The NS1 antigen test (Bio-Rad Laboratories, USA) was found positive and the patient was followed-up with diagnosis of dengue fever in India. During his visit to Turkey, he attended to the hospital for a routine control and his analysis revealed thrombocytopenia (PLT: 48.000/µl), leukopenia (white blood cell: 2800/µL) and elevated liver enzymes (AST: 76 U/L, ALT: 83 U/L). Fever was not detected in follow-up. The patient had petechial rash on his lower extremities. white blood cell and PLT count increased to 4100/µl and 93.000/µl, respectively. Liver function tests revealed a decrease in AST (63 U/L) and ALT (78 U/L) on the third day. The PLT count increased to 150.000/ml. Since the patient had no fever and had normal physical and laboratory findings, he was discharged from the hospital. For the confirmation of dengue fever diagnosis the serum sample was sent to National Public Health Center, Virology Reference and Research Laboratory where IgM and IgG antibodies against DENV types 1-4 were investigated by indirect immunofluorescence method (Euroimmun, Germany). The serum sample yielded positive result at the dilutions of 1/1000 for IgM and 1/10.000 for IgG. The last dilution of type 3 DENV IgM and IgG were determined high density of fluorescein, thus the serotype was identified as "DENV type 3". Travel-related diseases become important

  10. FREQUENCY OF SPLENOMEGALY IN DENGUE FEVER IN CHILDREN.

    Science.gov (United States)

    Arshad, Kashan; Sheikh, Saifuliah; Naqvi, Syeda Umm-ul-Baneen; Sarwar, Imran; Javaid, Sulman; Asghar, Madiha; Butt, Muhammad Asghar

    2015-01-01

    Dengue Fever is caused by arthropod born viruses. According to World Health Organization approximately 50-100 million infections of dengue fever occur yearly. Objective of this study was to determine the frequency of splenomegaly in dengue fever in children. This cross sectional study was conducted at the Department of Paediatrics, Allied Hospital, Faisalabad, during a period from June 2012 to May 2013 by including 93 Children, aged 4-14 years presenting with fever of less than 14 days with thrombocytopenia and positive IM or IgM and IgG dengue antibodies by ELISA. Patients were thoroughly evaluated by detailed history and clinical examination. Ultrasonography of the patients was performed to confirm the splenomegaly. The data was analysed to determine the frequency and percentage of disease. Out of 93 children, 51 (54.8%) were male and 42 (45.2%) were female. The most common clinical presentation was noted is chills and rigors in 80 (86.02%). Unusual clinical features were encephalopathy in 3T (39.78%) followed by bleeding manifestations and upper respiratory tract infection (upper RTI). Splenomegaly was seen in 45 (48.4%) children. Dengue fever is increasingly presenting with atypical presentation like splenomegaly, encephalopathy, bleeding manifestations and upper RTI.

  11. Dengue in India

    OpenAIRE

    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 ...

  12. Dengue virus serotype 2 from a sylvatic lineage isolated from a patient with dengue hemorrhagic fever.

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    Jane Cardosa

    Full Text Available Dengue viruses circulate in both human and sylvatic cycles. Although dengue viruses (DENV infecting humans can cause major epidemics and severe disease, relatively little is known about the epidemiology and etiology of sylvatic dengue viruses. A 20-year-old male developed dengue hemorrhagic fever (DHF with thrombocytopenia (12,000/ul and a raised hematocrit (29.5% above baseline in January 2008 in Malaysia. Dengue virus serotype 2 was isolated from his blood on day 4 of fever. A phylogenetic analysis of the complete genome sequence revealed that this virus was a member of a sylvatic lineage of DENV-2 and most closely related to a virus isolated from a sentinel monkey in Malaysia in 1970. This is the first identification of a sylvatic DENV circulating in Asia since 1975.

  13. Dengue Virus Infection Perturbs Lipid Homeostasis in Infected Mosquito Cells

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    Perera, Rushika M.; Riley, Catherine; Isaac, Georgis; Hopf- Jannasch, Amber; Moore, Ronald J.; Weitz, Karl K.; Pasa-Tolic, Ljiljana; Metz, Thomas O.; Adamec, Jiri; Kuhn, Richard J.

    2012-03-22

    Dengue virus causes {approx}50-100 million infections per year and thus is considered one of the most aggressive arthropod-borne human pathogen worldwide. During its replication, dengue virus induces dramatic alterations in the intracellular membranes of infected cells. This phenomenon is observed both in human and vector-derived cells. Using high-resolution mass spectrometry of mosquito cells, we show that this membrane remodeling is directly linked to a unique lipid repertoire induced by dengue virus infection. Specifically, 15% of the metabolites detected were significantly different between DENV infected and uninfected cells while 85% of the metabolites detected were significantly different in isolated replication complex membranes. Furthermore, we demonstrate that intracellular lipid redistribution induced by the inhibition of fatty acid synthase, the rate-limiting enzyme in lipid biosynthesis, is sufficient for cell survival but is inhibitory to dengue virus replication. Lipids that have the capacity to destabilize and change the curvature of membranes as well as lipids that change the permeability of membranes are enriched in dengue virus infected cells. Several sphingolipids and other bioactive signaling molecules that are involved in controlling membrane fusion, fission, and trafficking as well as molecules that influence cytoskeletal reorganization are also up regulated during dengue infection. These observations shed light on the emerging role of lipids in shaping the membrane and protein environments during viral infections and suggest membrane-organizing principles that may influence virus-induced intracellular membrane architecture.

  14. Dengue virus infection perturbs lipid homeostasis in infected mosquito cells.

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    Rushika Perera

    Full Text Available Dengue virus causes ∼50-100 million infections per year and thus is considered one of the most aggressive arthropod-borne human pathogen worldwide. During its replication, dengue virus induces dramatic alterations in the intracellular membranes of infected cells. This phenomenon is observed both in human and vector-derived cells. Using high-resolution mass spectrometry of mosquito cells, we show that this membrane remodeling is directly linked to a unique lipid repertoire induced by dengue virus infection. Specifically, 15% of the metabolites detected were significantly different between DENV infected and uninfected cells while 85% of the metabolites detected were significantly different in isolated replication complex membranes. Furthermore, we demonstrate that intracellular lipid redistribution induced by the inhibition of fatty acid synthase, the rate-limiting enzyme in lipid biosynthesis, is sufficient for cell survival but is inhibitory to dengue virus replication. Lipids that have the capacity to destabilize and change the curvature of membranes as well as lipids that change the permeability of membranes are enriched in dengue virus infected cells. Several sphingolipids and other bioactive signaling molecules that are involved in controlling membrane fusion, fission, and trafficking as well as molecules that influence cytoskeletal reorganization are also up regulated during dengue infection. These observations shed light on the emerging role of lipids in shaping the membrane and protein environments during viral infections and suggest membrane-organizing principles that may influence virus-induced intracellular membrane architecture.

  15. Superinfection interference between dengue-2 and dengue-4 viruses in Aedes aegypti mosquitoes.

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    Muturi, Ephantus J; Buckner, Eva; Bara, Jeffrey

    2017-04-01

    Dengue virus consists of four antigenically distinct serotypes (DENV 1-4) that are transmitted to humans by Aedes aegypti and Aedes albopictus mosquitoes. In many dengue-endemic regions, co-circulation of two or more DENV serotypes is fairly common increasing the likelihood for exposure of the two vectors to multiple serotypes. We used a model system of DENV-2 and DENV-4 to investigate how prior exposure of Aedes aegypti to one DENV serotype affects its susceptibility to another serotype. Aedes aegypti mosquitoes were sequentially infected with DENV-2 and DENV-4 and the infection and dissemination rates for each virus determined. We found that prior infection of Ae. aegypti mosquitoes with DENV-4 rendered them significantly less susceptible to secondary infection with DENV-2. Although the results were not statistically significant, mosquitoes infected with DENV-2 were also less susceptible to secondary infection with DENV-4. The midgut dissemination and population dissemination rates for DENV-2 were significantly higher than those of DENV-4 when either virus was administered 7 days after administration of either a non-infectious blood meal or a blood meal containing a heterologous dengue serotype. These results demonstrate that superinfection interference between DENV serotypes is possible within Ae. aegypti mosquitoes, but its effect on DENV epidemiology may be dependent on the fitness of interacting serotypes. © 2017 John Wiley & Sons Ltd.

  16. Dengue fever imported from India. A report of 3 cases.

    Science.gov (United States)

    Blackburn, N K; Rawat, R

    1987-03-21

    After visiting Saudi Arabia and India a woman became ill within 1 week of her return to Durban. Dengue type 1 virus was isolated from acute-phase serum, and antibody seroconversion was demonstrated. This is the first case of dengue fever in the RSA since the 1926-1927 epidemic. The occurrence of this case, and 2 further suspected cases, emphasises the need for vigilance if another epidemic is to be avoided.

  17. A novel indirect ELISA for diagnosis of dengue fever.

    Science.gov (United States)

    Narayan, Rohan; Raja, Senthil; Kumar, Senthil; Sambasivam, Mohana; Jagadeesan, Raja; Arunagiri, Kavita; Krishnasamy, Kaveri; Palani, Gunasekaran

    2016-07-01

    Dengue fever (DF) is associated with significant morbidity and mortality in the tropical and sub-tropical regions of the world. Since there are no effective antiviral drugs for treatment, clinicians often rely on the accurate diagnosis of dengue fever to begin supportive therapy at early stages of the illness. The objective of this study was to develop an in-house dengue virus serotype 2 (DENV-2) non-structural protein- 5 (NS5) based indirect ELISA. DENV-2 was raised in Vero cells and the viral proteins were separated and subsequently the NS5 protein was eluted. Serum samples from primary and secondary dengue fever patients; and acute and convalescent samples from Japanese encephalitis (JE) and West Nile virus (WNV) cases were used to validate the ELISA. The assay was found to be 100 per cent specific in detecting DENV-2 specific antibodies from patient's serum. However, in terms of sensitivity, the assay could detect IgM antibodies only from 90 per cent of the primary dengue samples. The IgM/IgG ratio of the primary and secondary samples was 7.24 and 0.64, respectively. The results indicate that the DENV-2 NS5 ELISA is dengue group specific and can be used to differentiate dengue infection from other circulating Flavivirus infections. This NS5 ELISA can also be used to distinguish between primary and secondary dengue fever on the basis of IgM/IgG ratios. Further studies with larger sample sizes and different DENV serotypes are required to validate the ELISA.

  18. A novel indirect ELISA for diagnosis of dengue fever

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    Rohan Narayan

    2016-01-01

    Full Text Available Background & objectives: Dengue fever (DF is associated with significant morbidity and mortality in the tropical and sub-tropical regions of the world. Since there are no effective antiviral drugs for treatment, clinicians often rely on the accurate diagnosis of dengue fever to begin supportive therapy at early stages of the illness. The objective of this study was to develop an in-house dengue virus serotype 2 (DENV-2 non-structural protein- 5 (NS5 based indirect ELISA. Methods: DENV-2 was raised in Vero cells and the viral proteins were separated and subsequently the NS5 protein was eluted. Serum samples from primary and secondary dengue fever patients; and acute and convalescent samples from Japanese encephalitis (JE and West Nile virus (WNV cases were used to validate the ELISA. Results: The assay was found to be 100 per cent specific in detecting DENV-2 specific antibodies from patient′s serum. However, in terms of sensitivity, the assay could detect IgM antibodies only from 90 per cent of the primary dengue samples. The IgM/IgG ratio of the primary and secondary samples was 7.24 and 0.64, respectively. Interpretation & conclusions: The results indicate that the DENV-2 NS5 ELISA is dengue group specific and can be used to differentiate dengue infection from other circulating Flavivirus infections. This NS5 ELISA can also be used to distinguish between primary and secondary dengue fever on the basis of IgM/IgG ratios. Further studies with larger sample sizes and different DENV serotypes are required to validate the ELISA.

  19. Dengue in children

    NARCIS (Netherlands)

    Verhagen, L.M.; Groot, R. de

    2014-01-01

    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

  20. [Rhabdomyolysis associated with dengue fever in a lupic patient].

    Science.gov (United States)

    Verdolin, Louise D; Borner, Alice R; Mussi, Henrique; Gismondi, Ronaldo A; Schau, Bruno; Ramos, Ricardo C

    2014-01-01

    This report describes the case of a woman with systemic lupus erythematous (SLE) that developed rhabdomyolysis after being infected by dengue virus. There are only a few cases of SLE accompanied by rhabdomyolysis, none of them associated with dengue fever. Initially, the woman presented high fever, myalgia, muscular weakness, mild headache, polyarthralgia and thrombocytopenia reminding a lupus flare, but since the number of people infected by dengue at that time was high and the symptoms from both conditions are similar, a dengue serology was requested. After a few days, the patient developed rhabdomyolysis. She was then submitted to immunosuppressive drugs, urinary alkalization and vigorous hydration, which improved her muscle damage and inflammatory condition. The positive dengue serology was only available after the therapy above had been established. She was discharged in an asymptomatic state. This case demonstrates how alike dengue fever and a lupus flare are, warning clinicians that, especially during an epidemic, both diseases should be carefully differentiated in order to establish a correct and efficient therapy.

  1. Risk of Disease from Mosquito and Tick Bites

    Science.gov (United States)

    Insect repellents help reduce the risk of mosquito and tick bites, which can transmit diseases including West Nile Virus, malaria, encephalitis, yellow fever, dengue fever, chikungunya virus, Lyme disease, Rocky Mountain spotted fever, and ehrlichiosis.

  2. Ecology and control of dengue vector mosquitoes in Taiwan.

    Science.gov (United States)

    Chen, Y R; Hwang, J S; Guo, Y J

    1994-12-01

    Due to rapid urbanization, industrialization and social changes in recent years, the use of packing materials and tires has dramatically increased in the Taiwan area. What is more is that some parts of southern Taiwan are short of water resources and water preservation with huge containers becomes part of custom in those areas. Storage water containers, waste vessels and tires are good habitats for Aedes. Meanwhile, some persons traveling to dengue endemic countries bring the dengue disease back to Taiwan. Surveys taken since 1988 show that dengue occurs mainly in the urban and coastal areas where Aedes aegypti is prevalent. This species is the most important, if not the only, vector of dengue in Taiwan. It appears that the types of Aedes breeding have changed quickly. In dengue fever epidemic areas, the most popular breeding sites are ornamental containers (38.8%), storage water containers (30.1%), discarded containers (25.4%), receptacles (3.3%) and water collection in the basement (2.2%). In dengue fever epidemic areas, those building basements, huge water containers, waste vessels and waste tires in open fields are most difficult to clean up and manage and become the most popular Aedes habitats. We established a waste recycling system and promoted a breeding site reduction campaign for waste management, including the application of Temephos in containers to kill larvae. For the drinking water management, fish were released in water containers to prevent larval breeding. It should be mentioned that with the integrated pest control and regular inspections of Aedes larvae in Taiwan the density figures 1, 2-5, and 6 or above for Aedes aegypti were 38.7%, 42.9%, and 18.4%, respectively, in 1988, and in 1993 were 90.8%, 9.2% and 0%. The incidence of dengue fever cases has 98% decreased since 1988. In 1990 and 1993, there was no indigenous cases. We have concluded that integrated pest control is the best and most effective method for dengue fever control, including

  3. Guiding dengue vaccine development using knowledge gained from the success of the yellow fever vaccine.

    Science.gov (United States)

    Liang, Huabin; Lee, Min; Jin, Xia

    2016-01-01

    Flaviviruses comprise approximately 70 closely related RNA viruses. These include several mosquito-borne pathogens, such as yellow fever virus (YFV), dengue virus (DENV), and Japanese encephalitis virus (JEV), which can cause significant human diseases and thus are of great medical importance. Vaccines against both YFV and JEV have been used successfully in humans for decades; however, the development of a DENV vaccine has encountered considerable obstacles. Here, we review the protective immune responses elicited by the vaccine against YFV to provide some insights into the development of a protective DENV vaccine.

  4. Acute glomerulonephritis in dengue hemorrhagic fever: A rare case report

    Directory of Open Access Journals (Sweden)

    K R Meena

    2013-01-01

    Full Text Available An 11-year-old male child presented with fever, bodyache, swelling over the whole body, and oliguria. He had hypertension. Urine microscopy showed hematuria and glomerular casts. Renal functions were deranged and had low complement C3 level. Chest X-ray showed plural effusion and ultrasonography abdomen showed mild ascitis. The immunoglobulin (IgM and IgG enzyme-linked immunosorbent essay for dengue virus were positive. Diagnosis of dengue hemorrhagic fever with acute glomerulonephritis was made. He was managed with maintenance fluid, antihypertensive medicine and supportive care. He recovered gradually and was discharged 12 days after admission.

  5. Transient cutaneous hyperpigmentation of extremities following dengue fever

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    Shrikiran Aroor

    2014-07-01

    Full Text Available A 14 year old boy presented with fever and generalized flushing of skin of 1 week duration. His vital signs were normal. Examination revealed generalized blanching macular erythematous rash. Systemic examination was unremarkable except for tender hepatomegaly. Investigations revealed leucopenia, thrombocytopenia and normal hemoglobin with mildly elevated liver transaminases. NS 1 (Non-structural protein-1 antigen and IgM antibody titer for Dengue ELISA was positive suggesting dengue fever. He was managed symptomatically and he recovered. During his follow up after 2 weeks he presented with brownish discoloration of dorsum of both hands and feet.

  6. The Self-Regulation Model of Illness: Comparison between Zika and Dengue and Its Application to Predict Mosquito Prevention Behaviours in Malaysia, a Dengue-Endemic Country.

    Science.gov (United States)

    Wong, Li Ping; Alias, Haridah; Aghamohammadi, Nasrin; Sam, I-Ching; AbuBakar, Sazaly

    2016-12-06

    Perceptions about illnesses may influence self-care and preventive health behaviours. Illness perceptions of the Zika virus (ZIKV) infection were investigated under the framework of the Self-Regulation Model of Illness. Illness perception differences between ZIKV and dengue fever were also examined. Lastly, associations between illness perceptions of ZIKV with mosquito prevention practices were studied. Samples were drawn from landline telephone numbers using computer-assisted telephone interviewing in Malaysia. A total of 567 respondents completed the survey between February 2015 and May 2016. The median and interquartile range (IQR) for the total six dimensions of illness perceptions score was higher for dengue (23.0 (IQR 17.0-28.0)) than ZIKV (20.0 (IRQ 11.0-28.0)), p dengue (OR 2.372, 95% CI 1.300-4.327 vs. no friends who died of dengue) were more likely to have a higher total score for six illness perceptions for ZIKV compared to dengue. Multivariate analysis indicated that the best predictors for mosquito control practices after the ZIKV outbreak was declared a Public Health Emergency of International Concern, in descending order, were causes, control, timeline, and consequences dimensions of illness perception. Understanding the context in which a person perceives ZIKV may contribute to developing interventions that influence prevention behaviours.

  7. Alterations in the Aedes aegypti transcriptome during infection with West Nile, dengue and yellow fever viruses.

    Science.gov (United States)

    Colpitts, Tonya M; Cox, Jonathan; Vanlandingham, Dana L; Feitosa, Fabiana M; Cheng, Gong; Kurscheid, Sebastian; Wang, Penghua; Krishnan, Manoj N; Higgs, Stephen; Fikrig, Erol

    2011-09-01

    West Nile (WNV), dengue (DENV) and yellow fever (YFV) viruses are (re)emerging, mosquito-borne flaviviruses that cause human disease and mortality worldwide. Alterations in mosquito gene expression common and unique to individual flaviviral infections are poorly understood. Here, we present a microarray analysis of the Aedes aegypti transcriptome over time during infection with DENV, WNV or YFV. We identified 203 mosquito genes that were ≥ 5-fold differentially up-regulated (DUR) and 202 genes that were ≥ 10-fold differentially down-regulated (DDR) during infection with one of the three flaviviruses. Comparative analysis revealed that the expression profile of 20 DUR genes and 15 DDR genes was quite similar between the three flaviviruses on D1 of infection, indicating a potentially conserved transcriptomic signature of flaviviral infection. Bioinformatics analysis revealed changes in expression of genes from diverse cellular processes, including ion binding, transport, metabolic processes and peptidase activity. We also demonstrate that virally-regulated gene expression is tissue-specific. The overexpression of several virally down-regulated genes decreased WNV infection in mosquito cells and Aedes aegypti mosquitoes. Among these, a pupal cuticle protein was shown to bind WNV envelope protein, leading to inhibition of infection in vitro and the prevention of lethal WNV encephalitis in mice. This work provides an extensive list of targets for controlling flaviviral infection in mosquitoes that may also be used to develop broad preventative and therapeutic measures for multiple flaviviruses.

  8. Alterations in the Aedes aegypti transcriptome during infection with West Nile, dengue and yellow fever viruses.

    Directory of Open Access Journals (Sweden)

    Tonya M Colpitts

    2011-09-01

    Full Text Available West Nile (WNV, dengue (DENV and yellow fever (YFV viruses are (reemerging, mosquito-borne flaviviruses that cause human disease and mortality worldwide. Alterations in mosquito gene expression common and unique to individual flaviviral infections are poorly understood. Here, we present a microarray analysis of the Aedes aegypti transcriptome over time during infection with DENV, WNV or YFV. We identified 203 mosquito genes that were ≥ 5-fold differentially up-regulated (DUR and 202 genes that were ≥ 10-fold differentially down-regulated (DDR during infection with one of the three flaviviruses. Comparative analysis revealed that the expression profile of 20 DUR genes and 15 DDR genes was quite similar between the three flaviviruses on D1 of infection, indicating a potentially conserved transcriptomic signature of flaviviral infection. Bioinformatics analysis revealed changes in expression of genes from diverse cellular processes, including ion binding, transport, metabolic processes and peptidase activity. We also demonstrate that virally-regulated gene expression is tissue-specific. The overexpression of several virally down-regulated genes decreased WNV infection in mosquito cells and Aedes aegypti mosquitoes. Among these, a pupal cuticle protein was shown to bind WNV envelope protein, leading to inhibition of infection in vitro and the prevention of lethal WNV encephalitis in mice. This work provides an extensive list of targets for controlling flaviviral infection in mosquitoes that may also be used to develop broad preventative and therapeutic measures for multiple flaviviruses.

  9. Atypical respiratory complications of dengue fever

    Institute of Scientific and Technical Information of China (English)

    Naveen Kumar; AK Gadpayle; Deepshikha Trisal

    2013-01-01

    In last decade, dengue has emerged as one of the most important vector born disease.With increasing cases, uncommon presentations and complications are now commonly recognized. Here, we report two cases of rare pattern of respiratory involvement in dengue: acute respiratory distress syndrome and bronchiolitis with respiratory failure.

  10. HEMATOLOGICAL MANIFESTATIONS IN DENGUE FEVER – AN OBSERVATIONAL STUDY

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    Malathesha

    2014-02-01

    Full Text Available BACKGROUND: Dengue is a major preventable and treatable cause of morbidity and mortality among children and adults that occurs mainly in tropical and subtropical regions. Early diagnosis of dengue is important for provision of specific care which ensures marked reduction in the morbidity of the disease itself. OBJECTIVE: To evaluate hematological changes in serologically proven patients with clinical manifestations of Dengue in Bapuji & Chigateri Hospital, Davangere. METHODS: Clinical, hematological and serological information from Patients diagnosed with dengue infection in Bapuji & Chigateri hospital Davangere from April 2013 -June 2013. RESULTS: 221 cases of classic dengue predominated (90.2%, with mild clinical manifestations lacking complications. The main hematological findings were raised hematocrit (79.6%, lymphocytosis (66% monocytosis (84.6%, basophilia (52.9%, thrombocytopenia (100% and atypical lymphocytes (87%. In dengue hemorrhagic fever, thrombocytopenia was more prolonged and the number of atypical lymphocytes was higher, while the other hematological abnormalities presented daily evolution similar to those in classic dengue. The hematological changes observed in dengue presented according to the clinical course of the disease and its severity

  11. A retrospective survey of dengue fever among Japanese individuals staying in Manila, Philippines.

    Science.gov (United States)

    Hamada, Atsuo; Tada, Yuki; Fukushima, Shinji; Murata, Hidemi; Kikuchi, Hirohisa

    2016-01-01

    Dengue fever is a serious concern for Japanese people staying in Southeast Asia. In order to implement necessary prophylactic measures for dengue fever in this population, we investigated the characteristics of dengue fever among Japanese nationals living in Manila, Philippines. From 2012 to 2015, 175 Japanese expatriates were diagnosed with dengue fever at the medical clinic of the Japanese Association Manila, Inc. Most of the patients were employees of Japanese companies and their families and were long-term residents of Manila. Most patients were either dengue fever were reported. The reported number of patients with dengue fever has shown a decreasing trend: from 55 cases in 2012 to 53 in 2013, 31 in 2014, and 36 in 2015. The results of this survey could be useful for the development of effective dengue fever preventive measures such as health education and provision of information among not only Japanese but also other foreigners residing in endemic areas.

  12. The Utilization of Standard Deviational Ellipse (SDE) Model for the Analysis of Dengue Fever Cases in Banjar City 2013

    OpenAIRE

    Martya Rahmaniati; Tris Eryando; Dewi Susanna; Dian Pratiwi; Fajar Nugraha; Andri Ruliansah; Muhammad Umar Riandi

    2014-01-01

    Dengue Fever Disease is still regarded as an endemic disease in Banjar City. Information is still required to map dengue fever case distribution, mean center of case distribution, and the direction of dengue fever case dispersion in order to support the surveillance program in the relation to the vast area of the dengue fever disease control program. The objective of the research is to obtain information regarding the area of dengue fever disease distribution in Banjar City by utilizing the S...

  13. Trends of fluid requirement in dengue fever and dengue haemorrhagic fever: a single centre experience in Sri Lanka.

    Science.gov (United States)

    Kularatne, Senanayake A M; Weerakoon, Kosala G A D; Munasinghe, Ruwan; Ralapanawa, Udaya K; Pathirage, Manoji

    2015-04-08

    Meticulous fluid management is the mainstay of treatment in dengue fever that is currently governed by consensus guidelines rather than by strong research evidence. To examine this issue we audited the fluid requirement of a cohort of adult patients with dengue fever (DF) and dengue haemorrhagic fever (DHF) in a tertiary care clinical setting. This retrospective cohort study was conducted from July 2012 to January 2013 in Teaching Hospital, Peradeniya, Sri Lanka. Adult patients with confirmed dengue infection managed according to the national and WHO guidelines were included. Their fluid requirement was audited once data collection was over in both DF and DHF groups. Out of 302 patients, 209 (69%) had serological confirmation of dengue infection, comprising 62 (30%) patients gone into critical phase of DHF. Mean age of the DHF group was 30 years (range 12-63 years) and included more males (n = 42, 68%, p fever on admission and total duration of fever were 4 days and 6 days respectively. DHF group had high incidence of vomiting, abdominal pain and flushing, lowest platelet counts and highest haematocrit values compared to DF group. In DHF group, the mean total daily requirements of fluid from 2(nd) to 7(th) day were 2123, 2733, 2846, 2981, 3139 and 3154 milliliters respectively to maintain a safe haematocrit value and the vital parameters. However, in DF group the fluid requirement was lowest on 3(rd) day (2158 milliliters). DHF group had significantly high fluid requirement on 5(th) -7(th) day compared to DF group (p fever and again on 5(th) to 7(th) day of fever. Despite being an audit, these finding could be useful in future updates of guidelines and designing research.

  14. A STUDY ON HEPATIC DYSFUNCTION IN DENGUE FEVER

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    Joshy Krishnan

    2017-08-01

    Full Text Available BACKGROUND Dengue fever is a public health problem in India like many other countries. It causes epidemics almost each year in different parts of India causing a burden to our healthcare system. Apart from the classical manifestations, dengue fever causes involvement of different systems especially liver function. This fact is usually overlooked especially in peripheral centers. The aim of the study is to estimate the proportion of patients who develop liver function abnormalities in dengue fever to understand whether liver function abnormalities have any association with the prognosis in these patients. MATERIALS AND METHODS 150 patients admitted with confirmed dengue fever were studied. Clinical features and liver function alterations were checked during admission on 3-week follow up and again on 6-week follow up. The data was analysed with the software, SPSS version 21. RESULTS 100% of the patients had fever, headache and myalgia. Almost, all patients showed elevation of transaminase levels. SGOT level >2x upper limit of normal was observed in 86.7% patients. SGPT level >2x upper limit of normal was noticed in 54%. Serum bilirubin 1.3 was noted in 15.3%. INR value >1.3 was present in 8%. On 3 weeks and 6 weeks follow up, only a limited percentage of patients showed persistence of mild elevation of transaminase level and bilirubin level. In those who showed elevated SGOT, SGPT, bilirubin and INR values, the hospital stay was found prolonged. The death rate was 1.3% (2 patients. CONCLUSION Hepatic dysfunction is common in dengue fever. The severity of hepatic dysfunction showed a statistically significant association with mortality, duration of hospital stay and persistent hyperbilirubinaemia.

  15. Impact of combined vector-control and vaccination strategies on transmission dynamics of dengue fever: a model-based analysis.

    Science.gov (United States)

    Knerer, Gerhart; Currie, Christine S M; Brailsford, Sally C

    2015-06-01

    Dengue fever is a vector-borne disease prevalent in tropical and subtropical regions. It is an important public health problem with a considerable and often under-valued disease burden in terms of frequency, cost and quality-of-life. Recent literature reviews have documented the development of mathematical models of dengue fever both to identify important characteristics for future model development as well as to assess the impact of dengue control interventions. Such reviews highlight the importance of short-term cross-protection; antibody-dependent enhancement; and seasonality (in terms of both favourable and unfavourable conditions for mosquitoes). The compartmental model extends work by Bartley (2002) and combines the following factors: seasonality, age-structure, consecutive infection by all four serotypes, cross-protection and immune enhancement, as well as combined vector-host transmission. The model is used to represent dengue transmission dynamics using parameters appropriate for Thailand and to assess the potential impact of combined vector-control and vaccination strategies including routine and catch-up vaccination strategies on disease dynamics. When seasonality and temporary cross-protection between serotypes are included, the model is able to approximate the observed incidence of dengue fever in Thailand. We find vaccination to be the most effective single intervention, albeit with imperfect efficacy (30.2 %) and limited duration of protection. However, in combination, control interventions and vaccination exhibit a marked impact on dengue fever transmission. This study shows that an imperfect vaccine can be a useful weapon in reducing disease spread within the community, although it will be most effective when promoted as one of several strategies for combating dengue fever transmission.

  16. Multiplexed, Patterned-Paper Immunoassay for Detection of Malaria and Dengue Fever.

    Science.gov (United States)

    Deraney, Rachel N; Mace, Charles R; Rolland, Jason P; Schonhorn, Jeremy E

    2016-06-21

    Multiplex assays detect the presence of more than one analyte in a sample. For diagnostic applications, multiplexed tests save healthcare providers time and resources by performing many assays in parallel, minimizing the amount of sample needed and improving the quality of information acquired regarding the health status of a patient. These advantages are of particular importance for those diseases that present with general, overlapping symptoms, which makes presumptive treatments inaccurate and may put the patient at risk. For example, malaria and dengue fever are febrile illnesses transmitted through mosquito bites, and these common features make it difficult to obtain an accurate diagnosis by symptoms alone. In this manuscript, we describe the development of a multiplexed, patterned paper immunoassay for the detection of biomarkers of malaria and dengue fever: malaria HRP2, malaria pLDH, and dengue NS1 type 2. In areas coendemic for malaria and dengue fever, this assay could be used as a rapid, point-of-care diagnostic to determine the cause of a fever of unknown origin. The reagents required for each paper-based immunoassay are separated spatially within a three-dimensional device architecture, which allows the experimental conditions to be adjusted independently for each assay. We demonstrate the analytical performances of paper-based assays for each biomarker and we show that there is no significant difference in performance between the multiplexed immunoassay and those immunoassays performed in singleplex. Additionally, we spiked individual analytes into lysed human blood to demonstrate specificity in a clinically relevant sample matrix. Our results suggest multiplex paper-based devices can be an essential component of diagnostic assays used at the point-of-care.

  17. Dengue

    Science.gov (United States)

    Dengue is an infection caused by a virus. You can get it if an infected mosquito bites you. Dengue does not spread from person to person. It ... the world. Outbreaks occur in the rainy season. Dengue is rare in the United States. Symptoms include ...

  18. The status of dengue fever virus in South Africa--serological studies and diagnosis of a case of dengue fever.

    Science.gov (United States)

    Blackburn, N K; Meenehan, G; Aldridge, N

    1987-01-01

    To assess the possibility of a dengue epidemic occurring in South Africa 3 groups of survey sera and 2 groups of patients' sera, from a dengue high risk area of South Africa, were tested for antibodies to several flaviviruses. 3.8% (75/1951) of the survey sera and 9.2% (26/282) of the patients' sera had haemagglutination inhibition antibodies to one or more of the flaviviruses tested. One of 1951 survey sera had a spectrum of complement fixation antibody consistent with a primary dengue infection, and 5 of 282 patients' sera also had complement fixation antibodies to flavivirus antigens. These 5 positive patients had recently travelled to India but in only one was there an antibody spectrum unequivocably consistent with a primary dengue infection. Dengue virus type 1 was successfully isolated from this patient's acute serum. The susceptibility of the population to dengue virus infection, the presence of the main vector of dengue virus and the occurrence of imported cases of dengue fever emphasize the need for continuous vigilance.

  19. Symmetrical peripheral gangrene: Unusual complication of dengue fever.

    Science.gov (United States)

    Patel, M L; Sachan, Rekha; Verma, Amita; Shyam, Radhey

    2016-01-01

    Symmetrical peripheral gangrene (SPG) is a rare clinical entity, infective, and noninfective both types of etiologies are responsible. The basic underlying pathology in SPG is being disseminated intravascular coagulation and carries a high mortality. Here, we describe a 52-year-old male with dengue fever, who developed bilateral symmetrical dry gangrene of both hand and feet. His dengue IgM antibody was positive. All the peripheral pulses of the affected limbs were palpable. Color Doppler study of upper and lower limb vessels showed normal flow. The patient was managed with intravenous fluids, low molecular weight heparin, and fresh frozen plasma. His general condition was improved within 72 h with no further progression of gangrene. Clinician should suspect the possibility of SPG while dealing a case of dengue fever presenting as peripheral gangrene.

  20. Clinical predictors of dengue fever co-infected with leptospirosis among patients admitted for dengue fever - a pilot study.

    Science.gov (United States)

    Suppiah, Jeyanthi; Chan, Shie-Yien; Ng, Min-Wern; Khaw, Yam-Sim; Ching, Siew-Mooi; Mat-Nor, Lailatul Akmar; Ahmad-Najimudin, Naematul Ain; Chee, Hui-Yee

    2017-06-28

    Dengue and leptospirosis infections are currently two major endemics in Malaysia. Owing to the overlapping clinical symptoms between both the diseases, frequent misdiagnosis and confusion of treatment occurs. As a solution, the present work initiated a pilot study to investigate the incidence related to co-infection of leptospirosis among dengue patients. This enables the identification of more parameters to predict the occurrence of co-infection. Two hundred sixty eight serum specimens collected from patients that were diagnosed for dengue fever were confirmed for dengue virus serotyping by real-time polymerase chain reaction. Clinical, laboratory and demographic data were extracted from the hospital database to identify patients with confirmed leptospirosis infection among the dengue patients. Thus, frequency of co-infection was calculated and association of the dataset with dengue-leptospirosis co-infection was statistically determined. The frequency of dengue co-infection with leptospirosis was 4.1%. Male has higher preponderance of developing the co-infection and end result of shock as clinical symptom is more likely present among co-infected cases. It is also noteworthy that, DENV 1 is the common dengue serotype among all cases identified as dengue-leptospirosis co-infection in this study. The increasing incidence of leptospirosis among dengue infected patients has posed the need to precisely identify the presence of co-infection for the betterment of treatment without mistakenly ruling out either one of them. Thus, anticipating the possible clinical symptoms and laboratory results of dengue-leptospirosis co-infection is essential.

  1. The Significance of Prolonged and Saddleback Fever in Hospitalised Adult Dengue.

    Science.gov (United States)

    Ng, Deborah Hl; Wong, Joshua Gx; Thein, Tun-Linn; Leo, Yee-Sin; Lye, David C

    2016-01-01

    Dengue fever is gaining importance in Singapore with an increase in the number of cases and mortality in recent years. Although prolonged and saddleback fever have been reported in dengue fever, there are no specific studies on their significance in dengue. This study aims to examine the prevalence of prolonged and saddleback fever in dengue as well as their associations with dengue severity. A total of 2843 polymerase-chain reaction (PCR) confirmed dengue patients admitted to Tan Tock Seng Hospital from 2004 to 2008 were included in the study. Sixty-nine percent of them were male with a median age of 34 years. Prolonged fever (fever > 7 days duration) was present in 572 (20.1%) of patients. Dengue hemorrhagic fever (DHF), dengue shock syndrome (DSS) and severe dengue (SD) were significantly more likely to occur in patients with prolonged fever. Mucosal bleeding, anorexia, diarrhea, abdominal pain, nausea or vomiting, lethargy, rash, clinical fluid accumulation, hepatomegaly, nosocomial infection, leukopenia, higher neutrophil count, higher hematocrit, higher alanine transaminase (ALT) and aspartate transaminase (AST), higher creatinine, lower protein and prolonged activated partial thromboplastin time (APTT) were significantly associated with prolonged fever but not platelet count or prothrombin time (PT). Saddleback fever was present in 165 (5.8%). Although DHF and SD were more likely to occur in patients in those with saddleback fever, DSS was not. Compared with prolonged fever, saddleback fever did not show many significant associations except for diarrhea, abdominal pain, clinical fluid accumulation, hematocrit and platelet change, and lower systolic blood pressure. This study demonstrates that prolonged fever may be associated with various warning signs and more severe forms of dengue (SD, DSS, DHF), while saddleback fever showed associations with DHF and SD but not DSS. The presence of prolonged or saddleback fever in dengue patients should therefore prompt

  2. An outbreak of dengue fever in Peri Urban slums of Chandigarh, India, with special reference to entomological and climatic factors

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    Ratho R

    2005-12-01

    Full Text Available Backgrounds: Dengue viral infection is one of the most important public health problem in tropical countries. Aim: An outbreak of dengue fever was investigated in a periurban slum area of Chandigarh, India, during September to December, 2002. Materials and methods: Blood samples from 218 patients and 30 apparently healthy contacts were tested for dengue-specific immunoglobulin M (IgM and IgG antibodies including 80 acute samples collected within 5 days of illness were subjected for virus isolation in newborn mice. The average temperature, rainfall, and humidity of the epidemic year were compared with the number of dengue cases. Statistical analysis: statistical significance was found out using c2-test. Results: A total of 76 cases were positive by either dengue IgM capture assay (n=57 or virus isolation (n=17 or both (n=2. fifteen of nineteen viral isolates subjected for typing by type-specific multiplex reverse transcription-polymerase chain reaction were found to be of dengue virus. High rainfall and humidity with the temperature range from 21oc to 33oc during the months of August and September might have favored the breeding of mosquitoes, thus leading to an increase in the number of dengue cases in October and November, 2002. Conclusion: The present outbreak thus emphasizes the need for continuous sero epidemiological and entomological surveillance for the timely implementation of effective dengue control programme.

  3. SERUM LEVELS OF COPPER AND IRON IN DENGUE FEVER

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    Rajendiran SOUNDRAVALLY

    2015-08-01

    Full Text Available SUMMARY The role of trace elements in dengue virulence is not yet known. The present study assessed the serum levels of two micronutrients, copper and iron, in cases of dengue fever. The study involved 96 patients of whom 48 had either severe or non-severe forms of dengue (with and without warning signs, and the remaining 48 were patients with other febrile illnesses (OFI, used as controls. Serum levels of copper and iron were evaluated at admission and by the time of defervescence using commercially available kits. At admission, no difference in the level of serum copper was observed between cases and controls. In the group of dengue cases, the copper level was found to be significantly decreased in severe and non-severe cases with warning signs, compared to non-severe cases without warning signs. In contrast, by the time of defervescence the copper level was found to be increased in all dengue cases compared to OFI controls, but no difference was observed among dengue cases. Unlike OFI controls, dengue cases showed an increasing pattern of copper levels from admission until defervescence. On the other hand, no such significant differences were observed in the serum level of iron in the clinical groups, except for a decreased iron level found in severe cases, compared to non-severe dengue without warning signs. The results show that copper is associated with dengue severity and this finding emphasizes the need to investigate the involvement of trace elements in disease severity so as to improve the prognosis of dengue.

  4. Human and mosquito infections by dengue viruses during and after epidemics in a dengue-endemic region of Colombia.

    Science.gov (United States)

    Méndez, Fabián; Barreto, Mauricio; Arias, Juan F; Rengifo, Graciela; Muñoz, Jaime; Burbano, María E; Parra, Beatriz

    2006-04-01

    We conducted a study in a dengue-endemic area of Colombia to evaluate the dynamics of transmission of dengue viruses during and after epidemics. Information was simultaneously gathered about occurrence of infection in humans and mosquitoes every three months in four cities with endemic transmission. Viral isolation was confirmed in 6.7% of the persons and most were asymptomatic. Adult mosquito and larvae house indexes were not found associated with increased burden of disease. The only entomologic indicator related to dengue infection in humans was the pooled infection rate of mosquitoes. Aedes aegypti infection rates showed significant differences between the epidemic (10.68, 95% confidence interval [CI] = 7.04-15.62) and after epidemic periods of the study (6.15, 95% CI = 3.46-10.19). In addition, Ae. albopictus were also infected with dengue viruses. Increases in mosquito infection rates were associated with increases in human infection rates in the following trimester.

  5. Assessing key safety concerns of a Wolbachia-based strategy to control dengue transmission by Aedes mosquitoes

    Directory of Open Access Journals (Sweden)

    Jean Popovici

    2010-12-01

    Full Text Available Mosquito-borne diseases such as dengue fever, chikungunya or malaria affect millions of people each year and control solutions are urgently needed. An international research program is currently being developed that relies on the introduction of the bacterial endosymbiont Wolbachia pipientis into Aedes aegypti to control dengue transmission. In order to prepare for open-field testing releases of Wolbachia-infected mosquitoes, an intensive social research and community engagement program was undertaken in Cairns, Northern Australia. The most common concern expressed by the diverse range of community members and stakeholders surveyed was the necessity of assuring the safety of the proposed approach for humans, animals and the environment. To address these concerns a series of safety experiments were undertaken. We report in this paper on the experimental data obtained, discuss the limitations of experimental risk assessment and focus on the necessity of including community concerns in scientific research.

  6. AN EPIDEMIOLOGICAL STUDY, CLINICOPATHOLOGICAL CORRELATION AND MANAGEMENT OF DENGUE FEVER

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    Nisha

    2013-10-01

    Full Text Available ABSTRACT: BACKGROUND: Dengue fever is an arthropod borne viral syndrome. OBJ ECTIVE: This study evaluated the newer signs and symptoms, to come to a bedside diagnosis of dengue fever and to predict the prognosis on the basis of clinical features and investigations. METHODS: This was a prospective study and included children aged u pto 15 years, admitted in the pediatric ward over 2 year period. Dengue like fever was defined according to WHO guidelines and then newer signs and symptoms and lab investigations were looked for,and treated symptomatically according to WHO guidelines. R ESULTS: Most of the children included were in the age group of 6 - 12 years with mean age being 5.3 years. Male to female ratio was 1.3:1 . Maximum patients were seen in winter with peak in October. Out of 90 children 13.3 % of DF , 48.89 % DHF, 37.78% DSS. The newer clinical features were found to were Pruritus (80%on recovery ,retro orbital pain(35%,Anorexia 68% ,Sore throat 30% , Fever(100%, Scrotal oedema (10%, Loose stools(20%, Cardiomyopathy (10%, Encephalopathy (1%, Menorrhagia(20%. One child had presented with Autism /ADHD on followup. Mortality rate 8.8% and all belonged to DSS group. Poor prognostic factors for death were vomiting, tachypnea ,convulsions, fluid collection in lungs, abdomen ,altered sensorium, convulsions , raised SGPT and s econdary infections.Fluid therapy (Oral / IV was used in all Platelets and blood transfusion was given in 20% and 13.3 % respectively. Ionotropes were used for DSS cases. CONCLUSIONS: The timely appropriate identification and timely management of Dengue fever go a long way in reducing mortality in dengue

  7. Laboratory evaluation of Indian medicinal plants as repellents against malaria, dengue, and filariasis vector mosquitoes.

    Science.gov (United States)

    Govindarajan, Marimuthu; Sivakumar, Rajamohan

    2015-02-01

    Mosquito-borne diseases have an economic impact, including loss in commercial and labor outputs, particularly in countries with tropical and subtropical climates; however, no part of the world is free from vector-borne diseases. Mosquitoes are the carriers of severe and well-known illnesses such as malaria, arboviral encephalitis, dengue fever, chikungunya fever, West Nile virus, and yellow fever. These diseases produce significant morbidity and mortality in humans and livestock around the world. In view of the recently increased interest in developing plant origin insecticides as an alternative to chemical insecticides, in the present study, the repellent activity of crude hexane, ethyl acetate, benzene, chloroform, and methanol extracts of leaf of Erythrina indica and root of Asparagus racemosus were assayed for their repellency against three important vector mosquitoes, viz., Anopheles stephensi, Aedes aegypti, and Culex quinquefasciatus. The crude extract was applied on a membrane used for membrane feeding of unfed mosquitoes in a 1-ft cage. About 50 unfed 3-4-day-old laboratory-reared pathogen-free strains of A. stephensi, A. aegypti, and C. quinquefasciatus were introduced in a 1-ft cage fitted with a membrane with blood for feeding with temperature maintained at 37 °C through circulating water bath maintained at 40-45 °C. Three concentrations (1.0, 2.0, and 5.0 mg/cm(2)) of the crude extracts were evaluated. Repellents in E. indica afforded longer protection time against A. stephensi, A. aegypti, and C. quinquefasciatus than those in A. racemosus at 5.0 mg/cm(2) concentration, and the mean complete protection time ranged from 120 to 210 min with the different extracts tested. In this observation, these two plant crude extracts gave protection against mosquito bites; also, the repellent activity is dependent on the strength of the plant extracts. These results suggest that the leaf extract of E. indica and root extract of A. racemosus have the potential to

  8. Mapping intra-urban transmission risk of dengue fever with big hourly cellphone data.

    Science.gov (United States)

    Mao, Liang; Yin, Ling; Song, Xiaoqing; Mei, Shujiang

    2016-10-01

    Cellphone tracking has been recently integrated into risk assessment of disease transmission, because travel behavior of disease carriers can be depicted in unprecedented details. Still in its infancy, such an integration has been limited to: 1) risk assessment only at national and provincial scales, where intra-urban human movements are neglected, and 2) using irregularly logged cellphone data that miss numerous user movements. Furthermore, few risk assessments have considered positional uncertainty of cellphone data. This study proposed a new framework for mapping intra-urban disease risk with regularly logged cellphone tracking data, taking the dengue fever in Shenzhen city as an example. Hourly tracking records of 5.85 million cellphone users, combined with the random forest classification and mosquito activities, were utilized to estimate the local transmission risk of dengue fever and the importation risk through travels. Stochastic simulations were further employed to quantify the uncertainty of risk. The resultant maps suggest targeted interventions to maximally reduce dengue cases exported to other places, as well as appropriate interventions to contain risk in places that import them. Given the popularity of cellphone use in urbanized areas, this framework can be adopted by other cities to design spatio-temporally resolved programs for disease control. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. Understanding environmental and climatic influences on regional differences and spatio-temporalscale issues of dengue fever transmission in Puerto Rico

    Science.gov (United States)

    Serman, E. A.; Akanda, A. S. S.; Ginsberg, H. S.; Couret, J.

    2015-12-01

    Each year, there are an estimated 50-100 million cases of dengue fever worldwide, roughly 30 times the number of cases as 50 years ago, with some estimates even higher. Puerto Rico (PR) has experienced epidemic dengue activity since 1963, and the disease is currently endemic. Since 1990 there have been 4 large epidemics, the most recent in 2010 where there were nearly 27,000 cases reported, amounting to almost 1% of the island's total population. Because no vaccine is currently available, effective control is dependent on our ability to understand the complex relationship between environmental factors, mosquito vector ecology, and disease epidemiology. Dengue virus is transmitted primarily by Aedes aegypti mosquitoes, as humans are the preferred host for Ae. aegypti. The purpose of our analysis is to assess temporal and spatial patterns of dengue transmission in PR and relate this to both climatic and anthropogenic factors. Unlike past studies, which have used San Juan to represent the island as a whole, our research will investigate regional dynamics in dengue transmission, as preliminary results have shown significant differences in population density, disease incidence, and environmental and climatic variables. Data from the Passive Dengue Surveillance System of CDC, meteorological observations from NCDC, and remote sensing data from USGS and NASA will be used together to identify relationships between climate, urbanization, and dengue incidence for PR at various spatial and temporal scales. Preliminary climatic factors considered include precipitation, temperature, humidity, and soil moisture. Finally, we will assess measures of urbanization such as land cover, land use, population density, and infrastructure that can make regional differences in dengue incidence each year. Results from this study could help create early warning systems for dengue surveillance in Puerto Rico, and develop techniques that can be applied to other areas of the world.

  10. Central retinal vein occlusion concomitant with dengue fever.

    Science.gov (United States)

    Velaitham, Punithamalar; Vijayasingham, Nandini

    2016-01-01

    Dengue virus infection is on the rise and there is increasing number of ocular complications that are being reported. Most common ocular complications are macular edema, macular hemorrhages, and foveolitis. There are case reports on branch retinal vessel occlusions. Most of the ocular complications are attributed to the bleeding tendency and transudative process in dengue viral infection. This is a case report of ischemic central retinal vein occlusion (CRVO) concomitant with dengue fever. A 41 year old Malay female was admitted to medical ward and diagnosed to have "dengue fever with warning signs". On the day of admission she noted sudden onset of right eye blurring of vision. She presented to our clinic 1 week later. Ocular examination revealed right eye visual acuity of <20/1000 and ischaemic CRVO with macular edema. She had no other risk factors to develop retinal vein occlusion. She progressively developed proliferative retinopathy and received multiple laser therapy. There was no anterior segment neovascularization. However, her vision improved to only 20/400 despite of resolution of macular edema and new vessels elsewhere. Dengue virus infection is known to cause thrombocytopenia which can result in hemorrhagic events. It can also cause procoagulant state which can result in thrombotic events secondary to immune reaction. Awareness among treating physicians of such ocular complication which can result in significant morbidity for patient is necessary.

  11. Dengue Fever-Associated Maculopathy and Panuveitis in Australia.

    Science.gov (United States)

    Ooi, K G-J; Inglis, H; Paramanathan, N; Downie, J A; Hennessy, M P

    2016-01-01

    Purpose. To describe a case of dengue fever-associated maculopathy and panuveitis to raise awareness of these ophthalmic complications of dengue in Australia in the light of recent increasing numbers of outbreaks from equatorial through to tropical Australia. Case Report. A 37-year-old Caucasian Australian male returning from Cambodia presented with a bilateral dengue fever-associated maculopathy with left panuveitis diagnosed clinically and haematologically. Automated perimetry revealed bilateral paracentral scotomas while optical coherence tomography demonstrated the maculopathies to be of the diffuse retinal thickening type in the right eye and acute macular neuroretinopathy (AMN) type in the left eye. He was treated conservatively with only topical steroids and cycloplegia and made a full clinical visual recovery. Conclusion. Our case study underscores the importance of the awareness of the ophthalmic complications of dengue fever as despite their rarity they can be potentially sight threatening. The incidence of these complications is likely to rise in Australia with increased global warming and the distribution of Aedes aegypti into subtropical Australia.

  12. Physical Theory of Vaccine Design for Influenza and Dengue Fever

    Science.gov (United States)

    Deem, Michael

    2009-03-01

    The immune system normally protects the human host against death by infection. I will introduce a physical theory of the evolutionary dynamics that occurs in the antibody-mediated and T cell-mediated immune responses. The theory will be used to provide a mechanism for original antigenic sin, wherein an initial exposure to antigen can degrade the response of the immune system upon subsequent exposure to related, but different, antigens. A new order parameter to characterize antigenic distance will be introduced from the theory. This order parameter predicts effectiveness of the influenza vaccine more reliably than do results from animal model studies currently used by world health authorities. I will discuss how this order parameter might be a valuable new tool for making vaccine-related public health policy decisions. Next, I will briefly discuss dengue fever. Infection with, or vaccination against, one of the four serotypes of dengue fever typically increases susceptibility to dengue hemorrhagic fever from one of the other three serotypes. I will present a physical theory of this immunodominance and use this theory to quantify the predicted mitigation of immunodominance in a novel formulation of the dengue vaccine.

  13. Predicting Dengue Fever Outbreaks in French Guiana Using Climate Indicators

    Science.gov (United States)

    Adde, Antoine; Roucou, Pascal; Mangeas, Morgan; Ardillon, Vanessa; Desenclos, Jean-Claude; Rousset, Dominique; Girod, Romain; Briolant, Sébastien; Quenel, Philippe; Flamand, Claude

    2016-01-01

    Background Dengue fever epidemic dynamics are driven by complex interactions between hosts, vectors and viruses. Associations between climate and dengue have been studied around the world, but the results have shown that the impact of the climate can vary widely from one study site to another. In French Guiana, climate-based models are not available to assist in developing an early warning system. This study aims to evaluate the potential of using oceanic and atmospheric conditions to help predict dengue fever outbreaks in French Guiana. Methodology/Principal Findings Lagged correlations and composite analyses were performed to identify the climatic conditions that characterized a typical epidemic year and to define the best indices for predicting dengue fever outbreaks during the period 1991–2013. A logistic regression was then performed to build a forecast model. We demonstrate that a model based on summer Equatorial Pacific Ocean sea surface temperatures and Azores High sea-level pressure had predictive value and was able to predict 80% of the outbreaks while incorrectly predicting only 15% of the non-epidemic years. Predictions for 2014–2015 were consistent with the observed non-epidemic conditions, and an outbreak in early 2016 was predicted. Conclusions/Significance These findings indicate that outbreak resurgence can be modeled using a simple combination of climate indicators. This might be useful for anticipating public health actions to mitigate the effects of major outbreaks, particularly in areas where resources are limited and medical infrastructures are generally insufficient. PMID:27128312

  14. Dengue Fever-Associated Maculopathy and Panuveitis in Australia

    Science.gov (United States)

    Inglis, H.; Paramanathan, N.; Downie, J. A.; Hennessy, M. P.

    2016-01-01

    Purpose. To describe a case of dengue fever-associated maculopathy and panuveitis to raise awareness of these ophthalmic complications of dengue in Australia in the light of recent increasing numbers of outbreaks from equatorial through to tropical Australia. Case Report. A 37-year-old Caucasian Australian male returning from Cambodia presented with a bilateral dengue fever-associated maculopathy with left panuveitis diagnosed clinically and haematologically. Automated perimetry revealed bilateral paracentral scotomas while optical coherence tomography demonstrated the maculopathies to be of the diffuse retinal thickening type in the right eye and acute macular neuroretinopathy (AMN) type in the left eye. He was treated conservatively with only topical steroids and cycloplegia and made a full clinical visual recovery. Conclusion. Our case study underscores the importance of the awareness of the ophthalmic complications of dengue fever as despite their rarity they can be potentially sight threatening. The incidence of these complications is likely to rise in Australia with increased global warming and the distribution of Aedes aegypti into subtropical Australia. PMID:28078150

  15. The Research Advances of Dengue Fever%登革热的研究进展

    Institute of Scientific and Technical Information of China (English)

    郑秀君; 肖寒; 刘尹正泽

    2016-01-01

    登革热是登革病毒引起的,由蚊媒传播的急性传染性疾病,该病广泛流行于世界各地,具有传播迅速、发病率高的特点,是蚊媒传染最为严重的疾病。随着经济和旅游行业的发展,以及人口基数的不断增长,该病严重威胁着人类的身体健康和生命安全。本文就登革热的病原学、实验室检查、诊疗方案和预防控制措施研究现状进行综述,以期对登革热更好的防治提供借鉴。%Dengue fever is caused by the dengue virus and is an acute infectious diseases spread by mosquito-borne.It is widely popular around the world,with the characteristics of rapid spread and high incidence. With the development of economy and tourism industry,as well as the growing population,dengue fever seriously threaten to human health and life safety.In this paper,we will review the etiology,laboratory examination, diagnosis and treatment plan and status in the prevention and control measures in order to provide reference for the prevention and control of dengue fever.

  16. CLINICAL AND HAEMATOLOGICAL PROFILE OF DENGUE FEVER IN A TERTIARY CARE HOSPITAL AT KAKINADA

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    Madhavi

    2016-03-01

    Full Text Available BACKGROUND Dengue fever(DF with its severe manifestations such as DHF and DSS has emerged as a major public health problem of international concern.The geographical distribution has greatly expanded over the last 30 years, because of increased potential for breeding of Aedes aegypti. This has been prompted by demographic explosion, rapid growth of urban centers with strain on public services, such as potable water and augmented by rain water harvesting in diverse types of containers resulting in multiple storage practices. Today, Dengue ranks as the most important mosquito-borne viral disease in the world. Current estimates report that at least 112 countries are endemic for Dengue and about 40% of the world populations (2.5-3 billion people are at risk in tropics and sub-tropics. Annually, 100 million cases of dengue fever and half a million cases of DHF occur worldwide. Early recognition and prompt initiation of treatment are vital if disease related morbidity and mortality are to be limited. METHODS A total of 100 patients admitted to our hospital with fever (>38.5 0 F and IgM Dengue positive were studied at our institute, Rangaraya Medical College, Kakinada during Jan 2013 to Jan 2015. Out of 100 patients, 73(73% patients were diagnosed to have DF, 22(22% patients were diagnosed to have DHF and 5(5% patients were diagnosed to have DSS based on WHO criteria. The present study was conducted in Government General Hospital, Kakinada during 2013-2015. Informed consent was taken from all the patients during the study. STUDY DESIGN It is a prospective cohort study over a period of two years through sample and sampling techniques. A total of 100 patients admitted to the hospital with history of fever of more than 38.5 0 C and IgM Dengue positive cases were selected using purposive sampling techniques. They were followed from the onset of fever to time of recovery or discharge according to WHO discharge criteria whichever is earlier. The following

  17. Spatial distribution of the risk of dengue fever in southeast Brazil, 2006-2007

    Science.gov (United States)

    2011-01-01

    Background Many factors have been associated with circulation of the dengue fever virus and vector, although the dynamics of transmission are not yet fully understood. The aim of this work is to estimate the spatial distribution of the risk of dengue fever in an area of continuous dengue occurrence. Methods This is a spatial population-based case-control study that analyzed 538 cases and 727 controls in one district of the municipality of Campinas, São Paulo, Brazil, from 2006-2007, considering socio-demographic, ecological, case severity, and household infestation variables. Information was collected by in-home interviews and inspection of living conditions in and around the homes studied. Cases were classified as mild or severe according to clinical data, and they were compared with controls through a multinomial logistic model. A generalized additive model was used in order to include space in a non-parametric fashion with cubic smoothing splines. Results Variables associated with increased incidence of all dengue cases in the multiple binomial regression model were: higher larval density (odds ratio (OR) = 2.3 (95%CI: 2.0-2.7)), reports of mosquito bites during the day (OR = 1.8 (95%CI: 1.4-2.4)), the practice of water storage at home (OR = 2.5 (95%CI: 1.4, 4.3)), low frequency of garbage collection (OR = 2.6 (95%CI: 1.6-4.5)) and lack of basic sanitation (OR = 2.9 (95%CI: 1.8-4.9)). Staying at home during the day was protective against the disease (OR = 0.5 (95%CI: 0.3-0.6)). When cases were analyzed by categories (mild and severe) in the multinomial model, age and number of breeding sites more than 10 were significant only for the occurrence of severe cases (OR = 0.97, (95%CI: 0.96-0.99) and OR = 2.1 (95%CI: 1.2-3.5), respectively. Spatial distribution of risks of mild and severe dengue fever differed from each other in the 2006/2007 epidemic, in the study area. Conclusions Age and presence of more than 10 breeding sites were significant only for severe

  18. Findings at brain MRI in children with dengue fever and neurological symptoms.

    Science.gov (United States)

    Rastogi, Ruchi; Garg, Bhavya

    2016-01-01

    Dengue is a flavivirus of the genus arbovirus with four serotypes, from DEN 1 to DEN 4. There has been an increase in incidence of dengue infection in children in the tropics and subtropics. Dengue has a variable clinical presentation, with many patients being asymptomatic. Its clinical manifestations in children vary from fever and arthralgia to life-threatening dengue hemorrhagic fever and dengue shock syndrome. We describe MRI findings in children with neurological involvement including dengue encephalopathy, acute hypoxic injury and dengue encephalitis. Dengue encephalopathy is usually secondary to multisystem derangement such as shock, hepatitis, coagulopathy and concurrent bacterial infection and is relatively common. Dengue encephalitis from direct neuronal invasion is rare. Nonspecific changes are seen on brain MRI in dengue infection. Clinical and laboratory findings as well as outcome do not necessarily correspond with brain MRI findings.

  19. Findings at brain MRI in children with dengue fever and neurological symptoms

    Energy Technology Data Exchange (ETDEWEB)

    Rastogi, Ruchi; Garg, Bhavya [Indraprastha Apollo Hospitals, Department of Radiodiagnosis, New Delhi (India)

    2016-01-15

    Dengue is a flavivirus of the genus arbovirus with four serotypes, from DEN 1 to DEN 4. There has been an increase in incidence of dengue infection in children in the tropics and subtropics. Dengue has a variable clinical presentation, with many patients being asymptomatic. Its clinical manifestations in children vary from fever and arthralgia to life-threatening dengue hemorrhagic fever and dengue shock syndrome. We describe MRI findings in children with neurological involvement including dengue encephalopathy, acute hypoxic injury and dengue encephalitis. Dengue encephalopathy is usually secondary to multisystem derangement such as shock, hepatitis, coagulopathy and concurrent bacterial infection and is relatively common. Dengue encephalitis from direct neuronal invasion is rare. Nonspecific changes are seen on brain MRI in dengue infection. Clinical and laboratory findings as well as outcome do not necessarily correspond with brain MRI findings. (orig.)

  20. Adult survivorship of the dengue mosquito Aedes aegypti varies seasonally in central Vietnam.

    Science.gov (United States)

    Hugo, Leon E; Jeffery, Jason A L; Trewin, Brendan J; Wockner, Leesa F; Nguyen, Thi Yen; Nguyen, Hoang Le; Nghia, Le Trung; Hine, Emma; Ryan, Peter A; Kay, Brian H

    2014-02-01

    The survival characteristics of the mosquito Aedes aegypti affect transmission rates of dengue because transmission requires infected mosquitoes to survive long enough for the virus to infect the salivary glands. Mosquito survival is assumed to be high in tropical, dengue endemic, countries like Vietnam. However, the survival rates of wild populations of mosquitoes are seldom measured due the difficulty of predicting mosquito age. Hon Mieu Island in central Vietnam is the site of a pilot release of Ae. aegypti infected with a strain of Wolbachia pipientis bacteria (wMelPop) that induces virus interference and mosquito life-shortening. We used the most accurate mosquito age grading approach, transcriptional profiling, to establish the survival patterns of the mosquito population from the population age structure. Furthermore, estimations were validated on mosquitoes released into a large semi-field environment consisting of an enclosed house, garden and yard to incorporate natural environmental variability. Mosquito survival was highest during the dry/cool (January-April) and dry/hot (May-August) seasons, when 92 and 64% of Hon Mieu mosquitoes had survived to an age that they were able to transmit dengue (12 d), respectively. This was reduced to 29% during the wet/cool season from September to December. The presence of Ae. aegypti older than 12 d during each season is likely to facilitate the observed continuity of dengue transmission in the region. We provide season specific Ae. aegypti survival models for improved dengue epidemiology and evaluation of mosquito control strategies that aim to reduce mosquito survival to break the dengue transmission cycle.

  1. Adult survivorship of the dengue mosquito Aedes aegypti varies seasonally in central Vietnam.

    Directory of Open Access Journals (Sweden)

    Leon E Hugo

    2014-02-01

    Full Text Available The survival characteristics of the mosquito Aedes aegypti affect transmission rates of dengue because transmission requires infected mosquitoes to survive long enough for the virus to infect the salivary glands. Mosquito survival is assumed to be high in tropical, dengue endemic, countries like Vietnam. However, the survival rates of wild populations of mosquitoes are seldom measured due the difficulty of predicting mosquito age. Hon Mieu Island in central Vietnam is the site of a pilot release of Ae. aegypti infected with a strain of Wolbachia pipientis bacteria (wMelPop that induces virus interference and mosquito life-shortening. We used the most accurate mosquito age grading approach, transcriptional profiling, to establish the survival patterns of the mosquito population from the population age structure. Furthermore, estimations were validated on mosquitoes released into a large semi-field environment consisting of an enclosed house, garden and yard to incorporate natural environmental variability. Mosquito survival was highest during the dry/cool (January-April and dry/hot (May-August seasons, when 92 and 64% of Hon Mieu mosquitoes had survived to an age that they were able to transmit dengue (12 d, respectively. This was reduced to 29% during the wet/cool season from September to December. The presence of Ae. aegypti older than 12 d during each season is likely to facilitate the observed continuity of dengue transmission in the region. We provide season specific Ae. aegypti survival models for improved dengue epidemiology and evaluation of mosquito control strategies that aim to reduce mosquito survival to break the dengue transmission cycle.

  2. Bilateral acute visual loss from Rathke's cleft cyst apoplexy in a patient with dengue fever

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    Ana Cláudia De Franco Suzuki

    2014-10-01

    Full Text Available Hemorrhagic complications of optic pathway diseases are extremely rare causes of acute visual loss associated with dengue fever. In this paper we report a patient presenting with dengue fever and bilateral acute visual loss caused by chiasmal compression due to Rathke's cleft cyst apoplexy. Considering the importance of early diagnosis and treatment to visual recovery, apoplexy of sellar and suprasellar tumors should be considered in the differential diagnosis of patients with acute visual loss and dengue fever.

  3. Dengue fever in Pakistan:Challenges, priorities and measures

    Institute of Scientific and Technical Information of China (English)

    Javid Ali

    2015-01-01

    Currently, there is no huge scale study on threat aspects and incidence of dengue fever in Pakistan, as a result it must be carried out on a priority source. It is the responsibility of the government to establish local community based laboratories and excellence research center for dengue cure, awareness and prevalence. The ailment could be cured in proper and better way. The treatment of dengue is extremely difficult due to lack of available vaccines. A developing country like Pakistan cannot handle the problems due to lake of awareness, behavior of people, terrorisms and other socioeconomic factors of the country as well as government interest to cope the other problems as compared to this one. Therefore, more measures should be carried out to prevent the disease.

  4. Dengue fever in Pakistan: Challenges, priorities and measures

    Directory of Open Access Journals (Sweden)

    Javid Ali

    2015-10-01

    Full Text Available Currently, there is no huge scale study on threat aspects and incidence of dengue fever in Pakistan, as a result it must be carried out on a priority source. It is the responsibility of the government to establish local community based laboratories and excellence research center for dengue cure, awareness and prevalence. The ailment could be cured in proper and better way. The treatment of dengue is extremely difficult due to lack of available vaccines. A developing country like Pakistan cannot handle the problems due to lake of awareness, behavior of people, terrorisms and other socioeconomic factors of the country as well as government interest to cope the other problems as compared to this one. Therefore, more measures should be carried out to prevent the disease.

  5. Serum cytokine/chemokine profiles in patients with dengue fever (DF) and dengue hemorrhagic fever (FHD) by using protein array.

    Science.gov (United States)

    Oliveira, Renato Antonio Dos Santos; Cordeiro, Marli Tenório; Moura, Patrícia Muniz Mendes Freire de; Baptista Filho, Paulo Neves Bapti; Braga-Neto, Ulisses de Mendonça; Marques, Ernesto Torres de Azevedo; Gil, Laura Helena Vega Gonzales

    2017-04-01

    DENV infection can induce different clinical manifestations varying from mild forms to dengue fever (DF) or the severe hemorrhagic fever (DHF). Several factors are involved in the progression from DF to DHF. No marker is available to predict this progression. Such biomarker could allow a suitable medical care at the beginning of the infection, improving patient prognosis. The aim of this study was to compare the serum expression levels of acute phase proteins in a well-established cohort of dengue fever (DF) and dengue hemorrhagic fever (DHF) patients, in order to individuate a prognostic marker of diseases severity. The serum levels of 36 cytokines, chemokines and acute phase proteins were determined in DF and DHF patients and compared to healthy volunteers using a multiplex protein array and near-infrared (NIR) fluorescence detection. Serum levels of IL-1ra, IL-23, MIF, sCD40 ligand, IP-10 and GRO-α were also determined by ELISA. At the early stages of infection, GRO-α and IP-10 expression levels were different in DF compared to DHF patients. Besides, GRO-α was positively correlated with platelet counts and IP-10 was negatively correlated with total protein levels. These findings suggest that high levels of GRO-α during acute DENV infection may be associated with a good prognosis, while high levels of IP-10 may be a warning sign of infection severity. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Predicting local dengue transmission in Guangzhou, China, through the influence of imported cases, mosquito density and climate variability.

    Directory of Open Access Journals (Sweden)

    Shaowei Sang

    Full Text Available 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.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.Imported DF cases and mosquito

  7. Spatiotemporal causal modeling for the management of Dengue Fever

    Science.gov (United States)

    Yu, Hwa-Lung; Huang, Tailin; Lee, Chieh-Han

    2015-04-01

    Increasing climatic extremes have caused growing concerns about the health effects and disease outbreaks. The association between climate variation and the occurrence of epidemic diseases play an important role on a country's public health systems. Part of the impacts are direct casualties associated with the increasing frequency and intensity of typhoons, the proliferation of disease vectors and the short-term increase of clinic visits on gastro-intestinal discomforts, diarrhea, dermatosis, or psychological trauma. Other impacts come indirectly from the influence of disasters on the ecological and socio-economic systems, including the changes of air/water quality, living environment and employment condition. Previous risk assessment studies on dengue fever focus mostly on climatic and non-climatic factors and their association with vectors' reproducing pattern. The public-health implication may appear simple. Considering the seasonal changes and regional differences, however, the causality of the impacts is full of uncertainties. Without further investigation, the underlying dengue fever risk dynamics may not be assessed accurately. The objective of this study is to develop an epistemic framework for assessing dynamic dengue fever risk across space and time. The proposed framework integrates cross-departmental data, including public-health databases, precipitation data over time and various socio-economic data. We explore public-health issues induced by typhoon through literature review and spatiotemporal analytic techniques on public health databases. From those data, we identify relevant variables and possible causal relationships, and their spatiotemporal patterns derived from our proposed spatiotemporal techniques. Eventually, we create a spatiotemporal causal network and a framework for modeling dynamic dengue fever risk.

  8. Sonography in the Diagnosis and Assessment of Dengue Fever

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    V R Santhosh

    2014-01-01

    Full Text Available Objective: The objective of the following study is to determine the use of ultrasound as an important adjunct to clinical and laboratory profile in diagnosing dengue fever and in predicting the severity of the disease by correlating imaging features with platelet count. The variation in sonographic features seen in patients from different age groups was also studied. Materials and Methods: This is a retrospective study. 96 patients who were serologically diagnosed as having dengue fever between April and August 2012 were referred for ultrasound scanning of the abdomen and thorax and the imaging findings were analyzed. Results: Out of 96 sero-positive dengue cases, 64 (66.7% patients showed edematous gallbladder (GB wall thickening, 62 (64.5% patients showed ascites, 48 (50% patients had pleural effusion, 17 (17.7% patients had hepatomegaly, 16 (16.7% patients had splenomegaly and in 17 (17.7% patients ultrasound findings were normal. Edematous GB wall thickening, ascites and pleural effusion were the most common combination of findings in all age groups. Edematous GB wall thickening was seen in 97.8% of patients with platelet count of less than 40,000 along with ascites (86.9% and pleural effusion (58.6%. In patients with platelet count between 40,000 and 80,000 ascites was more common than edematous GB wall thickening. Significantly no abnormal sonographic finding was detected in patient with platelet count more than 150,000. Conclusion: Sonographic features of thickened GB wall, pleural effusion (bilateral or right side, ascites, hepatomegaly and splenomegaly should strongly favor the diagnosis of dengue fever in patients presenting with fever and associated symptoms, particularly during an epidemic. The degree of thrombocytopenia showed a significant direct relationship to abnormal ultrasound features.

  9. Sonography in the diagnosis and assessment of dengue Fever.

    Science.gov (United States)

    Santhosh, V R; Patil, Prashanth G; Srinath, M G; Kumar, Ashok; Jain, Aditi; Archana, M

    2014-01-01

    The objective of the following study is to determine the use of ultrasound as an important adjunct to clinical and laboratory profile in diagnosing dengue fever and in predicting the severity of the disease by correlating imaging features with platelet count. The variation in sonographic features seen in patients from different age groups was also studied. This is a retrospective study. 96 patients who were serologically diagnosed as having dengue fever between April and August 2012 were referred for ultrasound scanning of the abdomen and thorax and the imaging findings were analyzed. Out of 96 sero-positive dengue cases, 64 (66.7%) patients showed edematous gallbladder (GB) wall thickening, 62 (64.5%) patients showed ascites, 48 (50%) patients had pleural effusion, 17 (17.7%) patients had hepatomegaly, 16 (16.7%) patients had splenomegaly and in 17 (17.7%) patients ultrasound findings were normal. Edematous GB wall thickening, ascites and pleural effusion were the most common combination of findings in all age groups. Edematous GB wall thickening was seen in 97.8% of patients with platelet count of less than 40,000 along with ascites (86.9%) and pleural effusion (58.6%). In patients with platelet count between 40,000 and 80,000 ascites was more common than edematous GB wall thickening. Significantly no abnormal sonographic finding was detected in patient with platelet count more than 150,000. Sonographic features of thickened GB wall, pleural effusion (bilateral or right side), ascites, hepatomegaly and splenomegaly should strongly favor the diagnosis of dengue fever in patients presenting with fever and associated symptoms, particularly during an epidemic. The degree of thrombocytopenia showed a significant direct relationship to abnormal ultrasound features.

  10. Spontaneous splenic rupture: A rare presentation of dengue fever

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    Mainak Mukhopadhyay

    2014-01-01

    Full Text Available Spontaneous rupture of the spleen with hemoperitoneum is a very rare, but serious manifestation of dengue fever (DF. We report a case of a young female who was presented with atraumatic abdominal pain, hypovolemic shock, anemia, ascites and hepatosplenomegaly with a recent history of a febrile illness. Subsequent investigations proved the presence of hemoperitoneum with spontaneous splenic rupture with seropositivity for DF. Early diagnosis and conservative management in this case resulted in a favorable outcome.

  11. How does the dengue vector mosquito Aedes albopictus respond to global warming?

    Science.gov (United States)

    Jia, Pengfei; Chen, Xiang; Chen, Jin; Lu, Liang; Liu, Qiyong; Tan, Xiaoyue

    2017-03-11

    Global warming has a marked influence on the life cycle of epidemic vectors as well as their interactions with human beings. The Aedes albopictus mosquito as the vector of dengue fever surged exponentially in the last decade, raising ecological and epistemological concerns of how climate change altered its growth rate and population dynamics. As the global warming pattern is considerably uneven across four seasons, with a confirmed stronger effect in winter, an emerging need arises as to exploring how the seasonal warming effects influence the annual development of Ae. albopictus. The model consolidates a 35-year climate dataset and designs fifteen warming patterns that increase the temperature of selected seasons. Based on a recently developed mechanistic population model of Ae. albopictus, the model simulates the thermal reaction of blood-fed adults by systematically increasing the temperature from 0.5 to 5 °C at an interval of 0.5 °C in each warming pattern. The results show the warming effects are different across seasons. The warming effects in spring and winter facilitate the development of the species by shortening the diapause period. The warming effect in summer is primarily negative by inhibiting mosquito development. The warming effect in autumn is considerably mixed. However, these warming effects cannot carry over to the following year, possibly due to the fact that under the extreme weather in winter the mosquito fully ceases from development and survives in terms of diapause eggs. As the historical pattern of global warming manifests seasonal fluctuations, this study provides corroborating and previously ignored evidence of how such seasonality affects the mosquito development. Understanding this short-term temperature-driven mechanism as one chain of the transmission events is critical to refining the thermal reaction norms of the epidemic vector under global warming as well as developing effective mosquito prevention and control strategies.

  12. A STUDY ON KNOWLEDGE, ATTITUDE AND PRACTICES REGARDING DENGUE FEVER AMONG PEOPLE LIVING IN URBAN AREA OF JHANSI CITY (UP

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    Shubhanshu

    2014-12-01

    Full Text Available BACKGROUND: Dengue is the major public health problem leading to increase in disease burden in terms of disability and deaths. Despite the magnitude of problem no documented evidence exists in India, which reveals the awareness and practices of country’s adult population regarding dengue fever, its spread, symptoms, treatment and prevention. OBJECTIVES: To access the knowledge, attitude and practices among the people living in urban area of Jhansi city. MATERIAL AND METHODS: A field based cross-sectional study was conducted during April –July 2014 among 100 respondents (>18 years from 223 households of green park colony of urban area of Jhansi city. Simple random sampling was used for interview by using a pretested, structured questionnaire. Knowledge was recorded and classified. Data obtained were collected and analysed statistically by simple proportions and chi-square test. RESULTS: Of the total 100 respondents (59% were male. When the socio-demographic characteristics of the study population were analysed, majority were young adults (20-40 years and were literate. Majority of participants cited mosquito bite as the commonest mode of spread. About 80% of the respondents identify fever as the most common clinical symptom. Nearly half of the respondents had insufficient knowledge about the causative agent of dengue. Television and media were important source of information. Around 60% of respondents correctly reported biting time of mosquito vector. Most prevalent preventive method was coils, liquid vaporisers. CONCLUSION: The study indicated that the respondents were quite familiar with dengue. Need for information, education, and communication programme to identify barrier and provide positive preventive practices about dengue. We conclude that there is need to increase health promotion activities to increase knowledge which forms the basis for preventive practices as a part to control dengue.

  13. Dengue-associated kidney disease.

    Science.gov (United States)

    Lizarraga, Karlo J; Nayer, Ali

    2014-01-01

    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. Directory of Open Access Journals (DOAJ), Google Scholar, PubMed (NLM), LISTA (EBSCO) and Web of Science have been searched. 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. In the vast majority of cases, dengue infection and associated renal disorders are self-limited.

  14. Chikungunya: a reemerging infection spreading during 2010 dengue fever outbreak in National Capital Region of India.

    Science.gov (United States)

    Ramachandran, V G; Das, Shukla; Roy, Priyamvada; Hada, Vivek; Mogha, Narendra Singh

    2016-06-01

    Chikungunya fever is an important reemerging arbovirus illness, which is transmitted by the same vector as of dengue virus. Many cases of concurrent infections with multiple dengue virus serotypes have been reported in many countries. Also, concurrent infection with Chikungunya virus and dengue virus has been reported in the past in Delhi. Therefore, this study was done to detect Chikungunya IgM antibodies in suspected dengue fever patients. In this study, 1666 serum samples suspected of dengue fever and collected during the outbreak period (August 2010-December 2010) were tested for dengue IgM antibodies, of which 736 tested negative. Of the 736 dengue IgM negative sera, 666 were tested for Chikungunya IgM antibodies. The demographic profile and essential laboratory investigations were recorded. Chikungunya IgM was detected in 9.91 % of the patients. During the post-monsoon period though dengue dominated in numbers, the number of Chikungunya fever cases increased gradually followed by an abrupt decrease with the onset of winter. The Chikungunya IgM positive patients were suffering from fever of more than 5 days duration and had thrombocytopenia. Due to similarity in clinical features and vector transmitting dengue and Chikungunya virus, continuous surveillance of both dengue fever and Chikungunya fever is desirable for better management and epidemiological assessment.

  15. International travel of Korean children and Dengue fever: A single institutional analysis.

    Science.gov (United States)

    Choi, Soo Han; Kim, Yae Jean; Shin, Ji Hun; Yoo, Keon Hee; Sung, Ki Woong; Koo, Hong Hoe

    2010-06-01

    Dengue fever occurs in many popular tourist destinations and is increasingly imported by returning travelers in Korea. Since Korea is not an endemic country for dengue fever, pediatricians do not usually suspect dengue fever in febrile children even with typical presentation and exposure history. This study was performed to describe the international travel experiences and dengue fever in Korean children. Travel histories were collected based on questionnaires completed by all patients' guardians who visited the pediatric infectious diseases clinic at Samsung Medical Center from January 2008 to December 2008. For patients who were suspected of dengue fever, a serological test was performed. Five hundred and seventeen children visited the pediatric infectious diseases clinic for the first time during this period. About 30% of patients who responded to the questionnaire (101/339) had experienced international travel within the last 2 years. Four patients were diagnosed with dengue fever by serological test. Increasing numbers of Korean children visit dengue endemic areas and they may return home with dengue fever. Dengue fever should be suspected in patients who have a travel history to endemic areas.

  16. Anamnestic immune response to dengue and decreased severity of yellow fever

    Directory of Open Access Journals (Sweden)

    Ricardo O Izurieta

    2009-01-01

    Full Text Available A protective immunity against yellow fever, from cross-reactive dengue antibodies, has been hypothesized as an explanation for the absence of yellow fever in Southern Asia where dengue immunity is almost universal. This study evaluates the association between protective immunity from cross-reactive dengue antibodies with yellow fever infection and severity of the disease. The study population consisted of military personnel of a jungle garrison and its detachments located in the Ecuadorian Amazonian rainforest. The cross-sectional study employed interviews as well as seroepidemiological methods. Humoral immune response to yellow fever, Mayaro, Venezuelan equine encephalitis, Oropouche, and dengue 2 infections was assessed by evaluating IgM and IgG specific antibodies. Log-linear regression analysis was used to evaluate age and presence of antibodies, against dengue type 2 virus, as predictors of yellow fever infection or severe disease. During the seroepidemiological survey, presence of dengue antibodies among yellow fever cases were observed in 77.3% cases from the coastal region, where dengue is endemic, 14.3% cases from the Amazon and 16.7 % cases from the Andean region. Dengue cross-reactive antibodies were not significantly associated with yellow fever infection but significantly associated with severity of the disease. The findings of this study suggest that previous exposure to dengue infection may have induced an anamnestic immune response that did not prevent yellow fever infection but greatly reduced the severity of the disease.

  17. Meteorological Factors for Dengue Fever Control and Prevention in South China

    Science.gov (United States)

    Gu, Haogao; Leung, Ross Ka-Kit; Jing, Qinlong; Zhang, Wangjian; Yang, Zhicong; Lu, Jiahai; Hao, Yuantao; Zhang, Dingmei

    2016-01-01

    Dengue fever (DF) is endemic in Guangzhou and has been circulating for decades, causing significant economic loss. DF prevention mainly relies on mosquito control and change in lifestyle. However, alert fatigue may partially limit the success of these countermeasures. This study investigated the delayed effect of meteorological factors, as well as the relationships between five climatic variables and the risk for DF by boosted regression trees (BRT) over the period of 2005–2011, to determine the best timing and strategy for adapting such preventive measures. The most important meteorological factor was daily average temperature. We used BRT to investigate the lagged relationship between dengue clinical burden and climatic variables, with the 58 and 62 day lag models attaining the largest area under the curve. The climatic factors presented similar patterns between these two lag models, which can be used as references for DF prevention in the early stage. Our results facilitate the development of the Mosquito Breeding Risk Index for early warning systems. The availability of meteorological data and modeling methods enables the extension of the application to other vector-borne diseases endemic in tropical and subtropical countries. PMID:27589777

  18. Meteorological Factors for Dengue Fever Control and Prevention in South China.

    Science.gov (United States)

    Gu, Haogao; Leung, Ross Ka-Kit; Jing, Qinlong; Zhang, Wangjian; Yang, Zhicong; Lu, Jiahai; Hao, Yuantao; Zhang, Dingmei

    2016-08-31

    Dengue fever (DF) is endemic in Guangzhou and has been circulating for decades, causing significant economic loss. DF prevention mainly relies on mosquito control and change in lifestyle. However, alert fatigue may partially limit the success of these countermeasures. This study investigated the delayed effect of meteorological factors, as well as the relationships between five climatic variables and the risk for DF by boosted regression trees (BRT) over the period of 2005-2011, to determine the best timing and strategy for adapting such preventive measures. The most important meteorological factor was daily average temperature. We used BRT to investigate the lagged relationship between dengue clinical burden and climatic variables, with the 58 and 62 day lag models attaining the largest area under the curve. The climatic factors presented similar patterns between these two lag models, which can be used as references for DF prevention in the early stage. Our results facilitate the development of the Mosquito Breeding Risk Index for early warning systems. The availability of meteorological data and modeling methods enables the extension of the application to other vector-borne diseases endemic in tropical and subtropical countries.

  19. Severe neutropenia revealing a rare presentation of dengue fever: a case report.

    Science.gov (United States)

    Shourick, J; Dinh, A; Matt, M; Salomon, J; Davido, B

    2017-08-17

    Arboviruses are a common cause of fever in the returned traveler often associated with leucopenia, especially lymphopenia and thrombocytopenia. Transient neutropenia has been described in a few cases of arboviruses. However, prolonged and severe neutropenia (dengue fever, especially in the returned traveler in Europe. A 26-year-old healthy female without any medical past history, flying back from Thailand, presented a transient fever with severe neutropenia (dengue fever. Outcome was favorable without any antimicrobial therapy. Physicians should be wary of possible unusual presentation of dengue fever with prolonged neutropenia. Although such biological sign is more often associated with malaria or severe bacterial infection, it may be a sign of arbovirus.

  20. Investigation of the First Case of Dengue Virus Infection Acquired in Western Australia in Seven Decades: Evidence of Importation of Infected Mosquitoes?

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    Michael D A Lindsay

    2015-09-01

    Full Text Available In October 2013, a locally-acquired case of dengue virus (DENV infection was reported in Western Australia (WA where local dengue transmission has not occurred for over 70 years. Laboratory testing confirmed recent DENV infection and the case demonstrated a clinically compatible illness. The infection was most likely acquired in the Pilbara region in the northwest of WA. Follow up investigations did not detect any other locally-acquired dengue cases or any known dengue vector species in the local region, despite intensive adult and larval mosquito surveillance, both immediately after the case was notified in October 2013 and after the start of the wet season in January 2014. The mechanism of infection with DENV in this case cannot be confirmed. However, it most likely followed a bite from a single infected mosquito vector that was transiently introduced into the Pilbara region but failed to establish a local breeding population. This case highlights the public health importance of maintaining surveillance efforts to ensure that any incursions of dengue vectors into WA are promptly identified and do not become established, particularly given the large numbers of viraemic dengue fever cases imported into WA by travellers returning from dengue-endemic regions.

  1. The Self-Regulation Model of Illness: Comparison between Zika and Dengue and Its Application to Predict Mosquito Prevention Behaviours in Malaysia, a Dengue-Endemic Country

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    Li Ping Wong

    2016-12-01

    Full Text Available Perceptions about illnesses may influence self-care and preventive health behaviours. Illness perceptions of the Zika virus (ZIKV infection were investigated under the framework of the Self-Regulation Model of Illness. Illness perception differences between ZIKV and dengue fever were also examined. Lastly, associations between illness perceptions of ZIKV with mosquito prevention practices were studied. Samples were drawn from landline telephone numbers using computer-assisted telephone interviewing in Malaysia. A total of 567 respondents completed the survey between February 2015 and May 2016. The median and interquartile range (IQR for the total six dimensions of illness perceptions score was higher for dengue (23.0 (IQR 17.0–28.0 than ZIKV (20.0 (IRQ 11.0–28.0, p < 0.001. Respondents who planned to have children (OR 1.670, 95% CI 1.035–2.694 vs. no intention to have children and had friends or acquaintances who died of dengue (OR 2.372, 95% CI 1.300–4.327 vs. no friends who died of dengue were more likely to have a higher total score for six illness perceptions for ZIKV compared to dengue. Multivariate analysis indicated that the best predictors for mosquito control practices after the ZIKV outbreak was declared a Public Health Emergency of International Concern, in descending order, were causes, control, timeline, and consequences dimensions of illness perception. Understanding the context in which a person perceives ZIKV may contribute to developing interventions that influence prevention behaviours.

  2. Urban epidemic of dengue virus serotype 3 infection, Senegal, 2009.

    Science.gov (United States)

    Faye, Ousmane; Ba, Yamar; Faye, Oumar; Talla, Cheikh; Diallo, Diawo; Chen, Rubing; Mondo, Mireille; Ba, Rouguiétou; Macondo, Edgard; Siby, Tidiane; Weaver, Scott C; Diallo, Mawlouth; Sall, Amadou Alpha

    2014-03-01

    An urban epidemic of dengue in Senegal during 2009 affected 196 persons and included 5 cases of dengue hemorrhagic fever and 1 fatal case of dengue shock syndrome. Dengue virus serotype 3 was identified from all patients, and Aedes aegypti mosquitoes were identified as the primary vector of the virus.

  3. Detection of dengue virus in individual Aedes aegypti mosquitoes in Delhi, India

    Directory of Open Access Journals (Sweden)

    Kumar Vikram

    2015-01-01

    Interpretation & conclusion: The study concludes that there was high MIR in the identified localities of low and medium income groups. Estimation of MIR in a female Aedes mosquito in the existing arsenals for dengue surveillance would be an added advantage for early warning of dengue outbreak. The presence of infected mosquitoes in identified localities of Delhi was alarming and require rigorous vector surveillance so that the severe outbreaks can be prevented.

  4. [A Case of Dengue Fever and Subsequent Long-lasting Depression Accompanied by Alopecia in a Japanese Traveler Returning from Bali, Indonesia].

    Science.gov (United States)

    Hitani, Akihiro; Yamaya, Waka; To, Masako; Kano, Ichino; Honda-Hosono, Natsue; Takasaki, Tomohiko; Haruki, Kosuke

    2015-03-01

    Recovery from dengue fever is generally rapid and uneventful. However, recuperation is often prolonged and may be accompanied by noticeable depression. We present herein on a traveler to Indonesia who developed long-lasting depression after the classic symptoms of dengue fever such as fever, arthralgia, and macropapular rash had resolved. A previously healthy 42-year old japanese woman presented to the Travel Clinic of Seirei Yokohama Hospital with complaints of 4 days of fever, joint aches, bone pain, and a macropapular rash on her torso. She had returned from Bali 5 days previously. During her 1-week stay, one day was spent in rural, mountainous areas where she was exposed to several mosquito bites. The 1st serum sample collected 4 days after the disease onset gave positive result in the rapid dengue IgM antibody test and the rapid dengue NS1 antigen immunechromatographic test. The DENV-1 genome was detected with RT-PCR. Her 13-year old son, who had accompanied her, was also diagnosed as having dengue fever and he recovered without event. The Above-mentioned symptoms resolved within one week. However, the patient suffered from prolonged depression. She also noticed loss of hair 3 months after the disease onset Administration of a Serotonin-Noradrenalin Reuptake Inhibitor and a minor tranquillizer required to allow her requied to lead a normal life. Although she gradually felt better, it took approximately 2 years until she had recovered completely without taking any antidepressant and minor tranquillizer. It is a well-known fact in endemic countries that dengue fever could have an significant impact on the patients' mental well-being. However, it appears that physicians in non-endemic countries are not fully aware of the prolonged depression, which can occur subsequent to the acute illness. Follow-up consultations of returing travelers who have recoverd from dengu fever should be arranged to monitor their mental and emotional states closely.

  5. The Aquaporin gene family of the yellow fever mosquito, Aedes aegypti.

    Directory of Open Access Journals (Sweden)

    Lisa L Drake

    Full Text Available BACKGROUND: The mosquito, Aedes aegypti, is the principal vector of the Dengue and yellow fever viruses. During feeding, an adult female can take up more than its own body weight in vertebrate blood. After a blood meal females excrete large amounts of urine through their excretion system, the Malpighian tubules (MT. Diuresis starts within seconds after the mosquito starts feeding. Aquaporins (AQPs are a family of membrane transporters that regulate the flow of water, glycerol and other small molecules across cellular membranes in both prokaryotic and eukaryotic cells. Our aim was to identify aquaporins that function as water channels, mediating transcellular water transport in MTs of adult female Ae. aegypti. METHODOLOGY/PRINCIPAL FINDINGS: Using a bioinformatics approach we screened genome databases and identified six putative AQPs in the genome of Ae. aegypti. Phylogenetic analysis showed that five of the six Ae. aegypti AQPs have high similarity to classical water-transporting AQPs of vertebrates. Using microarray, reverse transcription and real time PCR analysis we found that all six AQPs are expressed in distinct patterns in mosquito tissues/body parts. AaAQP1, 4, and 5 are strongly expressed in the adult female MT. RNAi-mediated knockdown of the MT-expressed mosquito AQPs resulted in significantly reduced diuresis. CONCLUSIONS/SIGNIFICANCE: Our results support the notion that AQP1, 4, and 5 function as water transporters in the MTs of adult female Ae. aegypti mosquitoes. Our results demonstrate the importance of these AQPs for mosquito diuresis after blood ingestion and highlight their potential as targets for the development of novel vector control strategies.

  6. On the analysis of effectiveness in mass application of mosquito repellent for dengue disease prevention

    Science.gov (United States)

    Aldila, D.; Soewono, E.; Nuraini, N.

    2012-05-01

    Dengue disease has been known as one of dangerous vector-borne diseases and become serious threat in many tropical countries. With no vaccine and antiviral available until nowadays, and frequent appearance of extraordinary dengue outbreaks, many governments are forced to declare national problem for dengue. At this moment, the only method available to prevent dengue disease transmission is to combat the disease-carrying mosquitoes as well as to reduce the contact between human and mosquitoes. The fast growing dengue transmission in many countries in recent years indicates that the mosquito control programs are far from successful. The use of mosquito repellent is one possible instrument which could be used as an effective mass treatment to prevent the dengue outbreak during endemic period. Here in this paper a Susceptible-Infectious-Recovered (S-I-R) dengue transmission model with repellent mass treatment is being applied to portions of children and adult compartments. Analysis of the basic reproductive ratio (Ro) of the model is done. It is shown, with reasonable choices of portions of treated children and adults, in combination with reduction of mosquito population, the basic reproductive ratio can be significantly reduced and occurrence of endemic can be avoided. Numerical simulations are shown for various treatment scenarios.

  7. Travelling waves in the occurrence of dengue haemorrhagic fever in Thailand

    Science.gov (United States)

    Cummings, Derek A. T.; Irizarry, Rafael A.; Huang, Norden E.; Endy, Timothy P.; Nisalak, Ananda; Ungchusak, Kumnuan; Burke, Donald S.

    2004-01-01

    Dengue fever is a mosquito-borne virus that infects 50-100 million people each year. Of these infections, 200,000-500,000 occur as the severe, life-threatening form of the disease, dengue haemorrhagic fever (DHF). Large, unanticipated epidemics of DHF often overwhelm health systems. An understanding of the spatial-temporal pattern of DHF incidence would aid the allocation of resources to combat these epidemics. Here we examine the spatial-temporal dynamics of DHF incidence in a data set describing 850,000 infections occurring in 72 provinces of Thailand during the period 1983 to 1997. We use the method of empirical mode decomposition to show the existence of a spatial-temporal travelling wave in the incidence of DHF. We observe this wave in a three-year periodic component of variance, which is thought to reflect host-pathogen population dynamics. The wave emanates from Bangkok, the largest city in Thailand, moving radially at a speed of 148km per month. This finding provides an important starting point for detecting and characterizing the key processes that contribute to the spatial-temporal dynamics of DHF in Thailand.

  8. Dengue in Java, Indonesia: Relevance of Mosquito Indices as Risk Predictors.

    Science.gov (United States)

    Wijayanti, Siwi P M; Sunaryo, Sunaryo; Suprihatin, Suprihatin; McFarlane, Melanie; Rainey, Stephanie M; Dietrich, Isabelle; Schnettler, Esther; Biek, Roman; Kohl, Alain

    2016-03-01

    No vaccine is currently available for dengue virus (DENV), therefore control programmes usually focus on managing mosquito vector populations. Entomological surveys provide the most common means of characterising vector populations and predicting the risk of local dengue virus transmission. Despite Indonesia being a country strongly affected by DENV, only limited information is available on the local factors affecting DENV transmission and the suitability of available survey methods for assessing risk. We conducted entomological surveys in the Banyumas Regency (Central Java) where dengue cases occur on an annual basis. Four villages were sampled during the dry and rainy seasons: two villages where dengue was endemic, one where dengue cases occurred sporadically and one which was dengue-free. In addition to data for conventional larvae indices, we collected data on pupae indices, and collected adult mosquitoes for species identification in order to determine mosquito species composition and population density. Traditionally used larval indices (House indices, Container indices and Breteau indices) were found to be inadequate as indicators for DENV transmission risk. In contrast, species composition of adult mosquitoes revealed that competent vector species were dominant in dengue endemic and sporadic villages. Our data suggested that the utility of traditional larvae indices, which continue to be used in many dengue endemic countries, should be re-evaluated locally. The results highlight the need for validation of risk indicators and control strategies across DENV affected areas here and perhaps elsewhere in SE Asia.

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

    Science.gov (United States)

    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...

  10. The changing incidence of Dengue Haemorrhagic Fever in Indonesia : A 45-year registry-based analysis

    NARCIS (Netherlands)

    Karyanti, Mulya R.; Uiterwaal, Cuno S P M; Kusriastuti, Rita; Hadinegoro, Sri R.; Rovers, Maroeska M.; Heesterbeek, Hans; Hoes, Arno W.; Bruijning-Verhagen, Patricia

    2014-01-01

    Background: Increases in human population size, dengue vector-density and human mobility cause rapid spread of dengue virus in Indonesia. We investigated the changes in dengue haemorrhagic fever (DHF) incidence in Indonesia over a 45-year period and determined age-specific trends in annual DHF incid

  11. The changing incidence of Dengue Haemorrhagic Fever in Indonesia: a 45-year registry-based analysis

    NARCIS (Netherlands)

    Karyanti, M.R.; Uiterwaal, C.S.; Kusriastuti, R.; Hadinegoro, S.R.; Rovers, M.M.; Heesterbeek, H.; Hoes, A.W.; Bruijning-Verhagen, P.

    2014-01-01

    BACKGROUND: Increases in human population size, dengue vector-density and human mobility cause rapid spread of dengue virus in Indonesia. We investigated the changes in dengue haemorrhagic fever (DHF) incidence in Indonesia over a 45-year period and determined age-specific trends in annual DHF incid

  12. The changing incidence of Dengue Haemorrhagic Fever in Indonesia: a 45-year registry-based analysis

    NARCIS (Netherlands)

    Karyanti, M.R.; Uiterwaal, C.S.P.M.; Kusriastuti, R.; Hadinegoro, S.R.; Rovers, M.M.; Heesterbeek, J.A.P.; Hoes, A.W.; Bruijning-Verhagen, P.

    2014-01-01

    Background: Increases in human population size, dengue vector-density and human mobility cause rapid spread of dengue virus in Indonesia. We investigated the changes in dengue haemorrhagic fever (DHF) incidence in Indonesia over a 45-year period and determined age-specific trends in annual DHF incid

  13. The changing incidence of Dengue Haemorrhagic Fever in Indonesia : A 45-year registry-based analysis

    NARCIS (Netherlands)

    Karyanti, Mulya R.; Uiterwaal, Cuno S P M; Kusriastuti, Rita; Hadinegoro, Sri R.; Rovers, Maroeska M.; Heesterbeek, Hans; Hoes, Arno W.; Bruijning-Verhagen, Patricia

    2014-01-01

    Background: Increases in human population size, dengue vector-density and human mobility cause rapid spread of dengue virus in Indonesia. We investigated the changes in dengue haemorrhagic fever (DHF) incidence in Indonesia over a 45-year period and determined age-specific trends in annual DHF

  14. 湖北省郧县2010年登革热蚊媒监测结果分析%Analysis on mosquito vectors surveillance results of dengue fever in Yun county of Hubei province in 2010

    Institute of Scientific and Technical Information of China (English)

    崔小波; 胡晓东; 杨玖栓

    2011-01-01

    Objective To understand the seasonal growth regularity of Aedes albopictus larvae and adult in Yun county , Hubei province, and provide scientific basis for control it. Method The larval indexs ( BI ( CI, HI) and adult densities of Aedes albopictus were surveillance at the last third of every month by field survey. Results The larvaes of Aedes albopictus were found in April at the earliest and latest in November, the larvae indexs ascended from April to June and reached to the peak in June (BI =84, CI =56, HI =50), and then descended month by month. The adults of Aedes albopictus were found from May to November, the density ascended from May to August, and reached to the peak in August (20 per person hour), and then descended month by month. Conclusions The seasonal growth regularity of the larvae and adult of Aedes albopictus were obviously, the larvae indexs were higher during May to September, the risk of dengue fever outbreak caused by imported infection was higher, therefore we should enhance environmental punish and disease surveillance.%目的 了解湖北省郧县登革热媒介白纹伊蚊幼虫和成蚊季节性消长规律,为登革热的防控提供科学依据.方法 每月下旬对监测点进行现场调查,监测白纹伊蚊的幼虫指数(BI、CI、HI)和成蚊密度.结果 最早监测到白纹伊蚊幼虫为4月,最晚为11月,4~6月幼虫指数逐月长升,6月最高(BI=84、CI=56、HI =50),后逐月下降.5~11月监测到白纹伊蚊成蚊,5~8月成蚊密度逐月上升,8月最高(20只/人工?h),后逐月下降结论 郧县白纹伊蚊幼虫和成蚊密度消长季节性明显,且5~9月幼虫指数较高,输人性登革热病例引起疫情暴发的风险较大,应加强环境整治和疾病监测.

  15. Dengue Dengue

    Directory of Open Access Journals (Sweden)

    Eric Martínez Torres

    2008-12-01

    Full Text Available El dengue es hoy la más importante arbovirosis, por su gran carga de enfermedad e implicaciones sociales. El mosquito Aedes aegypti, su principal transmisor convive con el hombre en su hábitat domestico y peridoméstico. El cuadro clínico es de fiebre, cefalea, dolor retroocular, dolores corporales, exantema y mucho decaimiento. El enfermo puede empeorar súbitamente y presentar choque por dengue, con grandes hemorragias digestivas y elevada mortalidad. No existe droga antiviral, pero la muerte puede evitarse mediante la infusión intravenosa precoz de soluciones cristaloides. Algunos candidatos vacunales están actualmente en ensayo clínico. La prevención depende del control del vector, mediante educación sanitaria y reordenamiento ambiental.Dengue is the most important arbovirosis in the World, with a huge burden of disease and social implications. It is transmitted by mosquitoes of the genus Aedes, particularly Aedes aegypti, that lives in the domestic and peridomestic habitat. The clinical picture includes fever, headache, retroorbital pain, body pains, rash and malaise. Sometimes patients has a sudden worsening with hypovolemic shock and hemorrhages, high an elevated lethality. Not an antiviral drug is available, but death can be prevented by early intravenous infusion of crystalloid solutions. Some vaccine candidates are being now evaluated. Prevention depends on vector control by health education and environmental reordering.

  16. Child-Invented Health Education Games: A Case Study for Dengue Fever

    Science.gov (United States)

    Lennon, Jeffrey L.; Coombs, David W.

    2006-01-01

    The study's goal was to demonstrate the ability of an 8-year-old child to create educational games for the topic of dengue fever control. A naturalistic descriptive case study method was employed. The child had two dengue fever educational game creation activities. The study demonstrated that a child could develop functional games related to…

  17. Child-Invented Health Education Games: A Case Study for Dengue Fever

    Science.gov (United States)

    Lennon, Jeffrey L.; Coombs, David W.

    2006-01-01

    The study's goal was to demonstrate the ability of an 8-year-old child to create educational games for the topic of dengue fever control. A naturalistic descriptive case study method was employed. The child had two dengue fever educational game creation activities. The study demonstrated that a child could develop functional games related to…

  18. Transition in the cause of fever from malaria to dengue, Northwestern Ecuador, 1990-2011.

    Science.gov (United States)

    Cifuentes, Sara G; Trostle, James; Trueba, Gabriel; Milbrath, Meghan; Baldeón, Manuel E; Coloma, Josefina; Eisenberg, Joseph N S

    2013-10-01

    In tropical areas, the predominant cause of fever has historically been malaria. However by 2011, among febrile patients in northwestern Ecuador, dengue was identified in 42% and malaria in none. This finding suggests a transition in the cause of fever from malaria to other illnesses, such as dengue.

  19. Demographic and Clinico-Epidemiological Features of Dengue Fever in Faisalabad, Pakistan

    Science.gov (United States)

    Raza, Faiz Ahmed; Rehman, Shafiq ur; Khalid, Ruqyya; Ahmad, Jameel; Ashraf, Sajjad; Iqbal, Mazhar; Hasnain, Shahida

    2014-01-01

    This cross-sectional study was carried out to explore the epidemiological and clinical features of dengue fever in Faisalabad, Pakistan during 2011 and 2012. During the study period, anti-dengue IgM positive cases were reported in the post-monsoon period during the months of August–December. Certain hotspots for the dengue infection were identified in the city that coincide with the clusters of densely populated urban regions of the city. Out of total 299 IgM positive patients (male 218 and female 81); there were 239 dengue fever (DF) and 60 dengue hemorrhagic fever (DHF) patients. There was decrease in the median age of dengue patients from 31 years in 2011 to 21.5 years in 2012 (pdengue fever. PMID:24595236

  20. Dengue and Chikungunya Vector Control Pocket Guide

    Science.gov (United States)

    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 ...

  1. Serological characterization of dengue virus infections observed among dengue hemorrhagic fever/dengue shock syndrome cases in upper Myanmar.

    Science.gov (United States)

    Ngwe Tun, Mya Myat; Thant, Kyaw Zin; Inoue, Shingo; Kurosawa, Yae; Lwin, Yee Yee; Lin, Sanda; Aye, Kay Thi; Thet Khin, Pe; Myint, Tin; Htwe, Khin; Mapua, Cynthia A; Natividad, Filipinas F; Hirayama, Kenji; Morita, Kouichi

    2013-07-01

    In Myanmar, dengue fever (DF)/dengue hemorrhagic fever (DHF) is one of the leading causes of morbidity and mortality among children. From Pyinmana Hospital in 2004 and Mandalay Children Hospital in 2006, 160 patients diagnosed clinically to have DHF/dengue shock syndrome (DSS) were examined for immunoglobulin M (IgM) and IgG levels. A focus reduction neutralization test was also used to determine primary or secondary dengue virus (DENV) infection. By using IgM-capture ELISA, 139 cases were confirmed as DENV infections. Of these IgM-positives, 94 samples were collected 7-24 days from the onset of illness, to which 13 (14%) and 81 (86%) were determined to be primary and secondary DENV infections, respectively. The 13 primary DENV infection cases were spread among the various severity groups (DHF grade I-IV and DSS) and represented age groups ranging from <1 year of age to 9 years of age. The patients in these primary infection cases showed a remarkably high IgM with a low IgG titer response compared with the secondary infection cases. No significant differences were observed in IgG titers with clinical severity. The data obtained in this study suggest that primary DENV infection cases exist certainly among DHF/DSS cases in Myanmar, and that additional mechanism(s) aside from the antibody-dependent enhancement mechanism could have influenced the clinical severity in DHF/DSS cases. Copyright © 2013 Wiley Periodicals, Inc.

  2. Arterial hypertension and skin allergy are risk factors for progression from dengue to dengue hemorrhagic fever: a case control study.

    Science.gov (United States)

    Teixeira, Maria Glória; Paixão, Enny S; Costa, Maria da Conceição N; Cunha, Rivaldo V; Pamplona, Luciano; Dias, Juarez P; Figueiredo, Camila A; Figueiredo, Maria Aparecida A; Blanton, Ronald; Morato, Vanessa; Barreto, Maurício L; Rodrigues, Laura C

    2015-05-01

    Currently, knowledge does not allow early prediction of which cases of dengue fever (DF) will progress to dengue hemorrhagic fever (DHF), to allow early intervention to prevent progression or to limit severity. The objective of this study is to investigate the hypothesis that some specific comorbidities increase the likelihood of a DF case progressing to DHF. A concurrent case-control study, conducted during dengue epidemics, from 2009 to 2012. Cases were patients with dengue fever that progressed to DHF, and controls were patients of dengue fever who did not progress to DHF. Logistic regression was used to estimate the association between DHF and comorbidities. There were 490 cases of DHF and 1,316 controls. Among adults, progression to DHF was associated with self-reported hypertension (OR = 1.6; 95% CI 1.1-2.1) and skin allergy (OR = 1.8; 95% CI 1.1-3.2) with DHF after adjusting for ethnicity and socio-economic variables. There was no statistically significant association between any chronic disease and progression to DHF in those younger than 15 years. Physicians attending patients with dengue fever should keep those with hypertension or skin allergies in health units to monitor progression for early intervention. This would reduce mortality by dengue.

  3. Enhancing knowledge and awareness of dengue during a prospective study of dengue fever.

    Science.gov (United States)

    Beckett, Charmagne G; Kosasih, Herman; Tan, Ratna; Widjaja, Susana; Listianingsih, Erlin; Ma'roef, Chairin; Wuryadi, Suharyono; Alisjahbana, Bachti; Rudiman, Irani; McArdle, James L; Porter, Kevin R

    2004-09-01

    In 1992, the Indonesian CDC implemented strategies to control and prevent dengue fever (DF) by including community involvement to reduce larva breeding sites and a mass health education program. To contribute to this effort, we incorporated an educational component into a prospective study of DF conducted at two textile factories in Bandung. This education provided: a lecture on the signs and symptoms of dengue and ways to prevent the disease, posters in the health clinic at each factory and handouts given to each volunteer with an explanation of symptoms. Upon enrollment, each participant completed a questionnaire to gather demographic information. Additionally they were given a brief (non-standardized) test (PRE-test) of their dengue knowledge, which was verbally administered by the study physicians. Five questions (15 point system) were designed to assess the participant's ability to recognize and describe aspects of dengue in lay terms. The subject material included: the symptoms of acute DF, transmission of dengue virus, and basic steps for disease prevention. The same questionnaire was re-administered 18 months later (POST-test), and the results were compared. A total of 2,340 participants completed both the PRE- and POST-tests; there were 1,373 males and 967 females, median age 36 years (range 18-59). Only 0.3% of participants scored EXCELLENT (15-14 points) on the PRE-test whereas 8.4% scored EXCELLENT on the POST-test. Fewer participants scored VERY BAD (2-0 points) on the POST-test compared to the PRE-test (1.4% vs 4.0%). The average raw scores for the PRE- and POST-tests were 7.8 and 10.1, respectively. Improvement of individual scores correlated highly with educational level. No significant correlation was identified for gender, age, factory location or a diagnosis of dengue during the study. These findings demonstrate that our prospective study enhanced knowledge and awareness of dengue in the volunteers.

  4. Spatial analysis of dengue fever in Guangdong Province, China, 2001-2006.

    Science.gov (United States)

    Liu, Chunxiao; Liu, Qiyong; Lin, Hualiang; Xin, Benqiang; Nie, Jun

    2014-01-01

    Guangdong Province is the area most seriously affected by dengue fever in China. In this study, we describe the spatial distribution of dengue fever in Guangdong Province from 2001 to 2006 with the objective of informing priority areas for public health planning and resource allocation. Annualized incidence at a county level was calculated and mapped to show crude incidence, excess hazard, and spatial smoothed incidence. Geographic information system-based spatial scan statistics was conducted to detect the spatial distribution pattern of dengue fever incidence at the county level. Spatial scan cluster analyses suggested that counties around Guangzhou City and Chaoshan Region were at increased risk for dengue fever (P dengue fever were found in Guangdong Province, which allowed intervention measures to be targeted for maximum effect.

  5. Taxonomy Icon Data: yellow fever mosquito [Taxonomy Icon

    Lifescience Database Archive (English)

    Full Text Available yellow fever mosquito Aedes aegypti Arthropoda Aedes_aegypti_L.png Aedes_aegypti_NL.png Aedes_aegypt...i_S.png Aedes_aegypti_NS.png http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Aedes+aegypti...&t=L http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Aedes+aegypti&t=NL http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Aedes+aegyp...ti&t=S http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Aedes+aegypti&t=NS ...

  6. Limited dengue virus replication in field-collected Aedes aegypti mosquitoes infected with Wolbachia.

    Directory of Open Access Journals (Sweden)

    Francesca D Frentiu

    2014-02-01

    Full Text Available INTRODUCTION: Dengue is one of the most widespread mosquito-borne diseases in the world. The causative agent, dengue virus (DENV, is primarily transmitted by the mosquito Aedes aegypti, a species that has proved difficult to control using conventional methods. The discovery that A. aegypti transinfected with the wMel strain of Wolbachia showed limited DENV replication led to trial field releases of these mosquitoes in Cairns, Australia as a biocontrol strategy for the virus. METHODOLOGY/PRINCIPAL FINDINGS: Field collected wMel mosquitoes that were challenged with three DENV serotypes displayed limited rates of body infection, viral replication and dissemination to the head compared to uninfected controls. Rates of dengue infection, replication and dissemination in field wMel mosquitoes were similar to those observed in the original transinfected wMel line that had been maintained in the laboratory. We found that wMel was distributed in similar body tissues in field mosquitoes as in laboratory ones, but, at seven days following blood-feeding, wMel densities increased to a greater extent in field mosquitoes. CONCLUSIONS/SIGNIFICANCE: Our results indicate that virus-blocking is likely to persist in Wolbachia-infected mosquitoes after their release and establishment in wild populations, suggesting that Wolbachia biocontrol may be a successful strategy for reducing dengue transmission in the field.

  7. Antibody responses to an immunodominant nonstructural 1 synthetic peptide in patients with dengue fever and dengue hemorrhagic fever.

    Science.gov (United States)

    Huang, J H; Wey, J J; Sun, Y C; Chin, C; Chien, L J; Wu, Y C

    1999-01-01

    Two flaviviruses, dengue (DEN) virus and Japanese encephalitis (JE) virus, are important because of their global distribution and the frequency of epidemics in tropical and subtropical areas. To study the B-cell epitopes of nonstructural 1 (NS1) glycoprotein and anti-NS1 antibody response in DEN infection, a series of 15-mer synthetic peptides from the predicted B-cell linear epitopes of DEN-2 NS1 protein were prepared. Enzyme-linked immunosorbent assay (ELISA) was performed to analyze antibody responses to these peptides from sera of both DEN and JE patients. One peptide derived from DEN-2 NS1, D2 NS1-P1 (amino acids 1-15), was identified as the immunodominant epitope that reacted with sera from dengue fever (DF) patients but not JE patients. The isotype of D2 NS1-P1-specific antibodies was mainly immunoglobulin M (IgM) in all sera that tested positive. A specificity study demonstrated that sera from all four DEN types reacted with D2 NS1-P1. A dynamics study showed that specific antibodies to this peptide could be detected as early as 2 days after the onset of symptoms. We observed significant anti-D2 NS1-P1 antibody responses in 45% of patients with primary and secondary infections with DF or with dengue hemorrhagic fever. This is the first report demonstrating that significant anti-DEN NS1 antibodies can be induced in the sera of patients with primary DEN infection.

  8. STUDY OF DENGUE FEVER IN SOUTH EASTERN RAJASTHAN

    Directory of Open Access Journals (Sweden)

    Sushma

    2015-02-01

    Full Text Available Dengue Fever has become a significant resurgent disease in the past 20 years all over the India. Our study outlines the clinical spectrum and prognosis of the disease beyond rural and urban confines. Study conducted on 350 patients admitted in SRG Hospital from the month April 2013 to Oct. 2013 about 7 months. All patients with the febrile illness pos itive for NS1 antigen , IgM and IgG/IgM antibody for Dengue virus were taken as case. The patients were subjected to clinical examination and baseline investigations so as to conduct study. The study was conducted to know the prevalence of dengue infection , based on laboratory rapid screening tests for NS1 , IgM and IgM/IgG antibodies and to study the seasonal variation and the clinical profile in these cases. Dengue causes increased morbidity and mortality and requires prompt diagnosis and treatment for the proper management of these cases , the rapid screening test for NS1 , IgM and IgM/IgG antibodies , platelet counts helps clinicians toward achieving this goal. The total number of patients were 350 of whom 180 were male and 170 were female. The most common pr esentation apart from fever , icterus , bodyache , rash , headache , gastrointestinal symptoms , haemorrhage and shock was present. Investigations revealed thrombocytopenia (<10 , 000 in 35 , (<25 , 000 in 120 , (<75 , 000 in 155 and (75000/cumm - 150000/cumm normal platelet counts in 40 patients. Leucopenia in 168 cases (<3000 were detected and HB. Values were raised. Case fatality rate is 1.7% in this study. Age group analysis revealed that it affects younger age persons 21 - 30 years. A febrile patients had r ash , myalgia and abdominal pain.

  9. Characterization of hemocytes from the yellow fever mosquito, Aedes aegypti.

    Science.gov (United States)

    Hillyer, Julián F; Christensen, Bruce M

    2002-05-01

    Mosquitoes are the most important arthropod disease vectors, transmitting a broad range of pathogens that cause diseases such as malaria, lymphatic filariasis, and yellow fever. Mosquitoes and other insects are able to mount powerful cellular and humoral immune responses against invading pathogens. To date, most studies have concentrated on the humoral response. In the current study we describe the hemocytes (blood cells) of the yellow fever mosquito, Aedes aegypti, by means of morphology, lectin binding, and enzyme activity and immunocytochemistry. Our light and electron microscopic studies suggest the presence of four distinct hemocyte types: granulocytes, oenocytoids, adipohemocytes, and thrombocytoids. We believe granulocytes and oenocytoids are true circulating hemocytes, but adipohemocytes and thrombocytoids are likely adhered to fixed tissues. Granulocytes, the most abundant cell type, have acid phosphatase and alpha-naphthyl acetate esterase activity, and bind the exogenous lectins WGA, HPA, and GNL. Phenoloxidase, an essential enzyme in the melanotic encapsulation immune response, was detected inside oenocytoids. This is, to our knowledge, the first report that has detected phenoloxidase inside mosquito hemocytes at the ultrastructural level. These results have begun to form a knowledge base for our ongoing studies on the function of Ae. aegypti hemocytes, and their involvement in controlling infections.

  10. An information value based analysis of physical and climatic factors affecting dengue fever and dengue haemorrhagic fever incidence

    Directory of Open Access Journals (Sweden)

    Tripathi Nitin

    2005-06-01

    Full Text Available Abstract Background Vector-borne diseases are the most dreaded worldwide health problems. Although many campaigns against it have been conducted, Dengue Fever (DF and Dengue Haemorrhagic Fever (DHF are still the major health problems of Thailand. The reported number of dengue incidences in 1998 for the Thailand was 129,954, of which Sukhothai province alone reported alarming number of 682. It was the second largest epidemic outbreak of dengue after 1987. Government arranges the remedial facilities as and when dengue is reported. But, the best way to control is to prevent it from happening. This will be possible only when knowledge about the relationship of DF/DHF with climatic and physio-environmental agents is discovered. This paper explores empirical relationship of climatic factors rainfall, temperature and humidity with the DF/DHF incidences using multivariate regression analysis. Also, a GIS based methodology is proposed in this paper to explore the influence of physio-environmental factors on dengue incidences. Remotely sensed data provided important data about physical environment and have been used for many vector borne diseases. Information Values (IV method was utilised to derive influence of various factors in the quantitative terms. Researchers have not applied this type of analysis for dengue earlier. Sukhothai province was selected for the case study as it had high number of dengue cases in 1998 and also due to its diverse physical setting with variety of land use/land cover types. Results Preliminary results demonstrated that physical factors derived from remotely sensed data could indicate variation in physical risk factors affecting DF/DHF. A composite analysis of these three factors with dengue incidences was carried out using multivariate regression analysis. Three empirical models ER-1, ER-2 and ER-3 were evaluated. It was found that these three factors have significant relation with DF/DHF incidences and can be related to

  11. Progress of the Research on the Efficacy of the Adult Mosquito as Vector for Transmitting Dengue Fever%成蚊传播登革病毒媒介效能的研究进展

    Institute of Scientific and Technical Information of China (English)

    宋秀玲; 黄炯烈; 郑小英; 吴瑜

    2005-01-01

    登革热(dengue fever,DF)和登革出血热(dengue hemorrhagic fever,DHF)是由黄病毒科黄病毒属的登革病毒(dengue virus,DV)引起,是我国南方重要的虫媒病。近年全球许多地区发病率也呈明显的上升趋势,已引起国际医学界高度重视。由于DF/DHF迄今尚无可用疫苗和药物预防或防治其发生和流行,媒介控制在DF/DHF流行的防治中起着重要作用,因而对媒介效能的研究具有实际的意义。

  12. Sialic acid expression in the mosquito Aedes aegypti and its possible role in dengue virus-vector interactions.

    Science.gov (United States)

    Cime-Castillo, Jorge; Delannoy, Philippe; Mendoza-Hernández, Guillermo; Monroy-Martínez, Verónica; Harduin-Lepers, Anne; Lanz-Mendoza, Humberto; Hernández-Hernández, Fidel de la Cruz; Zenteno, Edgar; Cabello-Gutiérrez, Carlos; Ruiz-Ordaz, Blanca H

    2015-01-01

    Dengue fever (DF) is the most prevalent arthropod-borne viral disease which affects humans. DF is caused by the four dengue virus (DENV) serotypes, which are transmitted to the host by the mosquito Aedes aegypti that has key roles in DENV infection, replication, and viral transmission (vector competence). Mosquito saliva also plays an important role during DENV transmission. In this study, we detected the presence of sialic acid (Sia) in Aedes aegypti tissues, which may have an important role during DENV-vector competence. We also identified genome sequences encoding enzymes involved in Sia pathways. The cDNA for Aedes aegypti CMP-Sia synthase (CSAS) was amplified, cloned, and functionally evaluated via the complementation of LEC29.Lec32 CSAS-deficient CHO cells. AedesCSAS-transfected LEC29.Lec32 cells were able to express Sia moieties on the cell surface. Sequences related to α-2,6-sialyltransferase were detected in the Aedes aegypti genome. Likewise, we identified Sia-α-2,6-DENV interactions in different mosquito tissues. In addition, we evaluated the possible role of sialylated molecules in a salivary gland extract during DENV internalization in mammalian cells. The knowledge of early DENV-host interactions could facilitate a better understanding of viral tropism and pathogenesis to allow the development of new strategies for controlling DENV transmission.

  13. Sialic Acid Expression in the Mosquito Aedes aegypti and Its Possible Role in Dengue Virus-Vector Interactions

    Science.gov (United States)

    Cime-Castillo, Jorge; Delannoy, Philippe; Mendoza-Hernández, Guillermo; Monroy-Martínez, Verónica; Lanz-Mendoza, Humberto; Hernández-Hernández, Fidel de la Cruz; Cabello-Gutiérrez, Carlos; Ruiz-Ordaz, Blanca H.

    2015-01-01

    Dengue fever (DF) is the most prevalent arthropod-borne viral disease which affects humans. DF is caused by the four dengue virus (DENV) serotypes, which are transmitted to the host by the mosquito Aedes aegypti that has key roles in DENV infection, replication, and viral transmission (vector competence). Mosquito saliva also plays an important role during DENV transmission. In this study, we detected the presence of sialic acid (Sia) in Aedes aegypti tissues, which may have an important role during DENV-vector competence. We also identified genome sequences encoding enzymes involved in Sia pathways. The cDNA for Aedes aegypti CMP-Sia synthase (CSAS) was amplified, cloned, and functionally evaluated via the complementation of LEC29.Lec32 CSAS-deficient CHO cells. AedesCSAS-transfected LEC29.Lec32 cells were able to express Sia moieties on the cell surface. Sequences related to α-2,6-sialyltransferase were detected in the Aedes aegypti genome. Likewise, we identified Sia-α-2,6-DENV interactions in different mosquito tissues. In addition, we evaluated the possible role of sialylated molecules in a salivary gland extract during DENV internalization in mammalian cells. The knowledge of early DENV-host interactions could facilitate a better understanding of viral tropism and pathogenesis to allow the development of new strategies for controlling DENV transmission. PMID:25874215

  14. Sialic Acid Expression in the Mosquito Aedes aegypti and Its Possible Role in Dengue Virus-Vector Interactions

    Directory of Open Access Journals (Sweden)

    Jorge Cime-Castillo

    2015-01-01

    Full Text Available Dengue fever (DF is the most prevalent arthropod-borne viral disease which affects humans. DF is caused by the four dengue virus (DENV serotypes, which are transmitted to the host by the mosquito Aedes aegypti that has key roles in DENV infection, replication, and viral transmission (vector competence. Mosquito saliva also plays an important role during DENV transmission. In this study, we detected the presence of sialic acid (Sia in Aedes aegypti tissues, which may have an important role during DENV-vector competence. We also identified genome sequences encoding enzymes involved in Sia pathways. The cDNA for Aedes aegypti CMP-Sia synthase (CSAS was amplified, cloned, and functionally evaluated via the complementation of LEC29.Lec32 CSAS-deficient CHO cells. AedesCSAS-transfected LEC29.Lec32 cells were able to express Sia moieties on the cell surface. Sequences related to α-2,6-sialyltransferase were detected in the Aedes aegypti genome. Likewise, we identified Sia-α-2,6-DENV interactions in different mosquito tissues. In addition, we evaluated the possible role of sialylated molecules in a salivary gland extract during DENV internalization in mammalian cells. The knowledge of early DENV-host interactions could facilitate a better understanding of viral tropism and pathogenesis to allow the development of new strategies for controlling DENV transmission.

  15. Unusual Presentation of Dengue Fever; A child with acute myocarditis

    Directory of Open Access Journals (Sweden)

    Moaz Aslam

    2016-02-01

    Full Text Available Dengue fever (DF is an acute febrile illness that follows a self-limiting course. However, some patients suffer from complications, including myocarditis, due to the involvement of other organs. A child presented at the Aga Khan University Hospital in Karachi, Pakistan, in June 2013 with a high-grade fever, malaise and epigastric pain radiating to the chest. Positive DF antigen and immunoglobulin M assays confirmed the diagnosis of DF. Persistent bradycardia with low blood pressure led to further cardiac investigations which showed a decreased ejection fraction and raised serum cardiac enzymes, indicating myocardial damage. With supportive care and use of inotropes, the spontaneous normalisation of cardiac enzyme levels and ejection fraction was observed. The child was discharged five days after admission. This case highlights the importance of identifying myocarditis in DF patients suffering from cardiac symptoms that are not explained by other potential aetiologies. Awareness, early suspicion and supportive care are essential to ensure favourable outcomes.

  16. Unusual Presentation of Dengue Fever: A child with acute myocarditis.

    Science.gov (United States)

    Aslam, Moaz; Aleem, Numra A; Zahid, Mohammad F; Rahman, Arshalooz J

    2016-02-01

    Dengue fever (DF) is an acute febrile illness that follows a self-limiting course. However, some patients suffer from complications, including myocarditis, due to the involvement of other organs. A child presented at the Aga Khan University Hospital in Karachi, Pakistan, in June 2013 with a high-grade fever, malaise and epigastric pain radiating to the chest. Positive DF antigen and immunoglobulin M assays confirmed the diagnosis of DF. Persistent bradycardia with low blood pressure led to further cardiac investigations which showed a decreased ejection fraction and raised serum cardiac enzymes, indicating myocardial damage. With supportive care and use of inotropes, the spontaneous normalisation of cardiac enzyme levels and ejection fraction was observed. The child was discharged five days after admission. This case highlights the importance of identifying myocarditis in DF patients suffering from cardiac symptoms that are not explained by other potential aetiologies. Awareness, early suspicion and supportive care are essential to ensure favourable outcomes.

  17. Municipality Level Simulations of Dengue Fever Incidence in Puerto Rico Using Ground Based and Remotely Sensed Climate Data

    Science.gov (United States)

    Quattrochi, Dale A.; Morin, Cory

    2015-01-01

    Dengue fever (DF) is caused by a virus transmitted between humans and Aedes genus mosquitoes through blood feeding. In recent decades incidence of the disease has drastically increased in the tropical Americas, culminating with the Pan American outbreak in 2010 which resulted in 1.7 million reported cases. In Puerto Rico dengue is endemic, however, there is significant inter-annual, intraannual, and spatial variability in case loads. Variability in climate and the environment, herd immunity and virus genetics, and demographic characteristics may all contribute to differing patterns of transmission both spatially and temporally. Knowledge of climate influences on dengue incidence could facilitate development of early warning systems allowing public health workers to implement appropriate transmission intervention strategies. In this study, we simulate dengue incidence in several municipalities in Puerto Rico using population and meteorological data derived from ground based stations and remote sensing instruments. This data was used to drive a process based model of vector population development and virus transmission. Model parameter values for container composition, vector characteristics, and incubation period were chosen by employing a Monte Carlo approach. Multiple simulations were performed for each municipality and the results were compared with reported dengue cases. The best performing simulations were retained and their parameter values and meteorological input were compared between years and municipalities. Parameter values varied by municipality and year illustrating the complexity and sensitivity of the disease system. Local characteristics including the natural and built environment impact transmission dynamics and produce varying responses to meteorological conditions.

  18. Primary dengue haemorrhagic fever in patients from northeast of Brazil is associated with high levels of interferon-β during acute phase

    Science.gov (United States)

    Oliveira, Renato Antônio dos Santos; da Silva, Mayara Marques Carneiro; Calzavara-Silva, Carlos Eduardo; Silva, Ana Maria; Cordeiro, Marli Tenório; de Moura, Patrícia Muniz Mendes Freire; Baptista, Paulo Neves; Marques, Ernesto Torres de Azevedo; Gil, Laura Helena Vega Gonzales

    2016-01-01

    Dengue is an acute febrile disease caused by the mosquito-borne dengue virus (DENV) that according to clinical manifestations can be classified as asymptomatic, mild or severe dengue. Severe dengue cases have been associated with an unbalanced immune response characterised by an over secretion of inflammatory cytokines. In the present study we measured type I interferon (IFN-I) transcript and circulating levels in primary and secondary DENV infected patients. We observed that dengue fever (DF) and dengue haemorrhagic fever (DHF) patients express IFN-I differently. While DF and DHF patients express interferon-α similarly (52,71 ± 7,40 and 49,05 ± 7,70, respectively), IFN- β were associated with primary DHF patients. On the other hand, secondary DHF patients were not able to secrete large amounts of IFN- β which in turn may have influenced the high-level of viraemia. Our results suggest that, in patients from our cohort, infection by DENV serotype 3 elicits an innate response characterised by higher levels of IFN- β in the DHF patients with primary infection, which could contribute to control infection evidenced by the low-level of viraemia in these patients. The present findings may contribute to shed light in the role of innate immune response in dengue pathogenesis. PMID:27223651

  19. The influence of humidity and temperature on the guangzhou dengue fever epidemic research%湿度与温度对广州市登革热传染病的影响研究

    Institute of Scientific and Technical Information of China (English)

    官金兰; 陈芷棋; 刘敏清; 梁嘉琪; 林晓佳; 邵思铭; 康军

    2016-01-01

    Based on mosquito-borne data in recent years, this paper analyzes the hotspots of mosquito-borne and the temperature and humidity factors affecting its growth. The prevalence of dengue fever in Guangzhou hot area is concluded. Thus the resources of dengue fever prevention and control can be reasonable allocated, and improve the response capacity of dengue fever outbreak.%本文以近年的蚊媒数据为依据,分析了蚊媒的热点地区及影响其生长的温度和湿度因素,归纳出广州登革热热点区的流行特点,从而合理配置登革热防控资源,实施更有效的防控措施,提高登革热疫情的应对能力。

  20. A hospital-based study of hepatic dysfunction in children with dengue fever

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    Surjeet Singh

    2015-12-01

    Full Text Available Objective: To study the hepatic dysfunction in children with dengue infection and find out its correlation with the severity of dengue fever. Methods: Seventy-two cases of dengue fever as per the World Health Organization aged from 2 months to 18 years of age guidelines serologically confirmed by dengue NS1 antigen detection or dengue IgM capture ELISA were studied for their hepatic dysfunction after excluding malaria, enteric fever, hepatitis A and hepatitis B. The duration of the study was from April 2013 to March 2014. Results: These 72 cases were grouped into severe dengue, dengue fever with warning sign and dengue fever without warning sign as per the World Health Organization guidelines. The spectrums of hepatic manifestations included hepatomegaly (66%, hepatic tenderness (44%, jaundice (9.72%, raised levels of aspartate transaminase (86%, alanine transaminase (90%, alkaline phosphatase (39%, prolonged prothrombin time (11% and reduced levels of serum albumin (66%. Conclusions: Tender hepatomegaly and elevated liver enzymes were seen more frequently in severe dengue. There was significant derangement between liver function and tender hepatomegaly. Altered liver function may be evident even in the absence of hepatomegaly.

  1. Risk associated with the release of Wolbachia-infected Aedes aegypti mosquitoes into the environment in an effort to control Dengue.

    Directory of Open Access Journals (Sweden)

    Justine V Murray

    2016-03-01

    Full Text Available Background: In an effort to eliminate dengue, a successful technology was developed with the stable introduction of the obligate intracellular bacteria Wolbachia pipientis into the mosquito Aedes aegypti to reduce its ability to transmit dengue fever due to life shortening and inhibition of viral replication effects. An analysis of risk was required before considering release of the modified mosquito into the environment.Methods: Expert knowledge and a risk assessment framework was used to identify risk associated with the release of the modified mosquito. Individual and group expert elicitation was performed to identify potential hazards. A Bayesian network (BN was developed to capture the relationship between hazards and the likelihood of events occurring. Risk was calculated from the expert likelihood estimates populating the BN and the consequence estimates elicited from experts.Results: The risk model for ‘Don’t Achieve Release’ provided an estimated 46% likelihood that the release would not occur by a nominated time, but generated an overall risk rating of very low. The ability to obtain compliance had the greatest influence on the likelihood of release occurring. The risk model for ‘Cause More Harm’ provided a 12.5% likelihood that more harm would result from the release, but the overall risk was considered negligible. The efficacy of mosquito management had the most influence, with the perception that the threat of dengue fever had been eliminated, resulting in less household mosquito control, was scored as the highest ranked individual hazard (albeit low risk.Conclusions: The risk analysis was designed to incorporate the interacting complexity of hazards that may affect the release of the technology into the environment. The risk analysis was a small but important implementation phase in the success of this innovative research introducing a new technology to combat dengue transmission in the environment.

  2. Protective and immunological behavior of chimeric yellow fever dengue vaccine.

    Science.gov (United States)

    Halstead, Scott B; Russell, Philip K

    2016-03-29

    Clinical observations from the third year of the Sanofi Pasteur chimeric yellow fever dengue tetravalent vaccine (CYD) trials document both protection and vaccination-enhanced dengue disease among vaccine recipients. Children who were 5 years-old or younger when vaccinated experienced a DENV disease resulting in hospitalization at 5 times the rate of controls. On closer inspection, hospitalized cases among vaccinated seropositives, those at highest risk to hospitalized disease accompanying a dengue virus (DENV) infection, were greatly reduced by vaccination. But, seronegative individuals of all ages after being vaccinated were only modestly protected from mild to moderate disease throughout the entire observation period despite developing neutralizing antibodies at high rates. Applying a simple epidemiological model to the data, vaccinated seronegative individuals of all ages were at increased risk of developing hospitalized disease during a subsequent wild type DENV infection. The etiology of disease in placebo and vaccinated children resulting in hospitalization during a DENV infection, while clinically similar are of different origin. The implications of the observed mixture of DENV protection and enhanced disease in CYD vaccinees are discussed.

  3. Febrile illness in a young traveler: dengue fever and its complications.

    Science.gov (United States)

    Duber, Herbert C; Kelly, Stephen M

    2013-10-01

    Dengue fever, a tropical disease once confined mostly to endemic areas in developing countries, is becoming more prevalent. Globalization has led to an increased incidence of the virus both in foreign travelers returning home and local outbreaks in traditionally nonendemic areas, such as the southern United States and southern Europe. Advances in diagnostic tests, therapies, and vaccines for dengue virus have been limited, but research is ongoing. To review the current literature regarding the diagnosis and management of dengue fever. This case report describes a young woman returning from Central America with many of the common signs and symptoms who was misdiagnosed both abroad and at home. We explore the epidemiology, disease course, complications, and treatment of dengue fever. Emergency physicians should consider dengue fever in patients with acute febrile illnesses, especially among those with recent travel. Copyright © 2013 Elsevier Inc. All rights reserved.

  4. Modeling the Geographic Consequence and Pattern of Dengue Fever Transmission in Thailand.

    Science.gov (United States)

    Bekoe, Collins; Pansombut, Tatdow; Riyapan, Pakwan; Kakchapati, Sampurna; Phon-On, Aniruth

    2017-05-04

    Dengue fever is one of the infectious diseases that is still a public health problem in Thailand. This study considers in detail, the geographic consequence, seasonal and pattern of dengue fever transmission among the 76 provinces of Thailand from 2003 to 2015. A cross-sectional study. The data for the study was from the Department of Disease Control under the Bureau of Epidemiology, Thailand. The quarterly effects and location on the transmission of dengue was modeled using an alternative additive log-linear model. The model fitted well as illustrated by the residual plots and the  Again, the model showed that dengue fever is high in the second quarter of every year from May to August. There was an evidence of an increase in the trend of dengue annually from 2003 to 2015. There was a difference in the distribution of dengue fever within and between provinces. The areas of high risks were the central and southern regions of Thailand. The log-linear model provided a simple medium of modeling dengue fever transmission. The results are very important in the geographic distribution of dengue fever patterns.

  5. Dengue fever in patients admitted in tertiary care hospitals in Pakistan.

    Science.gov (United States)

    Munir, Muhammad Arif; Alam, Syed Ejaz; Khan, Zareef Uddin; Saeed, Quaid; Arif, Ambreen; Iqbal, Rizwan; Saqib, Muhammad Arif Nadeem; Qureshi, Huma

    2014-05-01

    To assess the gaps in the diagnosis and management of dengue fever cases. The retrospective descriptive analytical study was done with a case record analysis of patients with dengue fever admitted from January to December 2010 at five tertiary care hospitals in different Pakistani cities. Using a questionnaire, information was gathered on demography, haematological profile, management, use of blood and platelet transfusions and the outcome. For comparison, data of serologically-confirmed dengue patients from a private laboratory in Islamabad was collected to see the age, gender and month-wise distribution of cases tested over the same period. SPSS 16 was used for statistical analysis. Out of the 841 confirmed dengue cases, 514 (79%) were males and 139 (21%) females. The overall mean age was 31.3 +/- 14.0 years. Dengue fever was seen in 653 (78%) and dengue haemorrhagic fever (DHF) in 188 (22%) patients. Most cases were between 20 and 49 years of age. A gradual increase in dengue fever and dengue haemorrhagic fever was seen from August, with a peak in October/November. Tourniquet test was done only in 20 (2.3%) cases, out of which 11 (55%) were positive and 9 (45%) were negative. Serial haematocrit was not done in any case. Total deaths were 5 (0.6%). Most cases were seen in October/November with the majority being in the 20-39 age group. Tourniquet test and serial haematocrit were infrequently used. No standard national guidelines were employed.

  6. Clinical and laboratory diagnosis of dengue fever in travelers

    Directory of Open Access Journals (Sweden)

    N. I. Khokhlova

    2015-01-01

    Full Text Available The paper presents the analysis of clinical and laboratory symptoms in 35 adult patients with denger fever, Novosibirsk residents, which travelled in endemic countries, mostly Tailand. The classic form of the disease was determined in all cases. The moderate form was in 71,5% patients, the severe form was in the rest ones. The diagnosis of dengue was verified by detection of specific immunoglobulin M and in some cases immunoglobulin G and also virus dengue NS1 antigen by immunochromatography. The dominant clinical symptoms in observed patients were fever for 3–8 days (100%, mostly high one (71,4%, asthenia (97,1%, anorexia (100%, myalgia or/and arthralgia (77,1%, exantema (60%, hepatomegaly (62,8%. The gematologic indicators were represented with thrombocytopenia in 91,4% patients (from 167 to 20×109/l и leucopenia in 85,7% patients (from 3,9 to 1,1×109/l. The cytolitic syndrom was revealed in 80% patients with predominance of aspartate aminotransferase activity in early period of the disease. 

  7. Multi-level analyses of spatial and temporal determinants for dengue infection

    NARCIS (Netherlands)

    S.O. Vanwambeke (Sophie); B.H.B. van Bethem (Birgit); N. Khantikul (Nardlada); C. Burghoorn-Maas; K. Panart (Kamolwan); L. Oskam (Linda); E. Lambin (Eric); P. Somboon (Pradya)

    2006-01-01

    textabstractBackground: 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

  8. Multi-level analyses of spatial and temporal determinants for dengue infection

    NARCIS (Netherlands)

    S.O. Vanwambeke (Sophie); B.H.B. van Bethem (Birgit); N. Khantikul (Nardlada); C. Burghoorn-Maas; K. Panart (Kamolwan); L. Oskam (Linda); E. Lambin (Eric); P. Somboon (Pradya)

    2006-01-01

    textabstractBackground: 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 site

  9. Susceptibility of Aedes flavopictus miyarai and Aedes galloisi mosquito species in Japan to dengue type 2 virus

    Institute of Scientific and Technical Information of China (English)

    Raweewan Srisawat; Thipruethai Phanitchat; Narumon Komalamisra; Naoki Tamori; Lucky Runtuwene; Kaori Noguchi; Kyoko Hayashida; Shinya Hidano; Naganori Kamiyama; Ikuo Takashima; Tomohiko Takasaki; Ichiro Kurae; Narihiro Narita; Takashi Kobayashi; Yuki Eshita

    2016-01-01

    Objective: To evaluate the potential of local mosquitoes to act as vectors for dengue transmission in Japan.Methods: Serotype 2 Th NH28/93 was used to test the dengue susceptibility profiles of Aedes flavopictus miyarai(Ae. f. miyarai), Aedes galloisi(Ae. galloisi) and Aedes albopictus(Ae.albopictus), which were collected in Japan. We used Aedes aegypti from Thailand as a positive control. The mosquitoes were infected with the virus intrathoracically or orally. At 10 or 14 days post infection, the mosquitoes were dissected and total RNA was extracted from their abdomens, thoraxes, heads and legs. Mosquito susceptibility to dengue virus was evaluated using RT-PCR with dengue virus-specific primers. Differences in the infection and mortality rates of the different mosquito species were tested using Fisher’s exact probability test.Results: The infection rates for dengue virus administered intrathoracically to Ae. f. miyarai,Ae. galloisi and Aedes aegypti mosquitoes were identical by RT-PCR on Day 10 post infection.All of the body parts we tested were RT-PCR-positive for dengue virus. For the orally administered virus, the infection rates in the different body parts of the Ae. f. miyarai mosquitoes were slightly higher than those of Ae. albopictus mosquitoes, but were similar to the control mosquitoes(P > 0.05). The mortality rates for Ae. f. miyarai and Ae. albopictus mosquitoes were similar(P = 0.19). Our data indicated that dengue virus was able to replicate and disseminate to secondary infection sites in all of the four mosquito species(Japanese and Thai).Conclusions: Ae. albopictus is a well-known candidate for dengue transmission in Japan. However, our data suggest that Ae. f. miyarai from Ishigaki Island(near Okinawa Island) and Ae. galloisi from Hokkaido(Northern Japan) should also be regarded as potential vectors for dengue transmission in these regions. Further studies on these mosquitoes should be conducted.

  10. Susceptibility of Aedes flavopictus miyarai and Aedes galloisi mosquito species in Japan to dengue type 2 virus

    Institute of Scientific and Technical Information of China (English)

    Raweewan Srisawat; Ikuo Takashima; Tomohiko Takasaki; Ichiro Kurae; Narihiro Narita; Takashi Kobayashi; Yuki Eshita; Thipruethai Phanitchat; Narumon Komalamisra; Naoki Tamori; Lucky Runtuwene; Kaori Noguchi; Kyoko Hayashida; Shinya Hidano; Naganori Kamiyama

    2016-01-01

    Objective: To evaluate the potential of local mosquitoes to act as vectors for dengue transmission in Japan. Methods: Serotype 2 ThNH28/93 was used to test the dengue susceptibility profiles of Aedes flavopictus miyarai (Ae. f. miyarai), Aedes galloisi (Ae. galloisi) and Aedes albopictus (Ae. albopictus), which were collected in Japan. We used Aedes aegypti from Thailand as a positive control. The mosquitoes were infected with the virus intrathoracically or orally. At 10 or 14 days post infection, the mosquitoes were dissected and total RNA was extracted from their abdomens, thoraxes, heads and legs. Mosquito susceptibility to dengue virus was evaluated using RT-PCR with dengue virus-specific primers. Differences in the infection and mortality rates of the different mosquito species were tested using Fisher's exact probability test. Results: The infection rates for dengue virus administered intrathoracically to Ae. f. miyarai, Ae. galloisi and Aedes aegypti mosquitoes were identical by RT-PCR on Day 10 post infection. All of the body parts we tested were RT-PCR-positive for dengue virus. For the orally admin-istered virus, the infection rates in the different body parts of the Ae. f. miyarai mosquitoes were slightly higher than those of Ae. albopictus mosquitoes, but were similar to the control mosquitoes (P>0.05). The mortality rates for Ae. f. miyarai and Ae. albopictus mosquitoes were similar (P=0.19). Our data indicated that dengue virus was able to replicate and disseminate to secondary infection sites in all of the four mosquito species (Japanese and Thai). Conclusions: Ae. albopictus is a well-known candidate for dengue transmission in Japan. However, our data suggest that Ae. f. miyarai from Ishigaki Island (near Okinawa Island) and Ae. galloisi from Hokkaido (Northern Japan) should also be regarded as potential vectors for dengue transmission in these regions. Further studies on these mosquitoes should be conducted.

  11. A False Positive Dengue Fever Rapid Diagnostic Test Result in a Case of Acute Parvovirus B19 Infection.

    Science.gov (United States)

    Izumida, Toshihide; Sakata, Hidenao; Nakamura, Masahiko; Hayashibara, Yumiko; Inasaki, Noriko; Inahata, Ryo; Hasegawa, Sumiyo; Takizawa, Takenori; Kaya, Hiroyasu

    2016-01-01

    An outbreak of dengue fever occurred in Japan in August 2014. We herein report the case of a 63-year-old man who presented with a persistent fever in September 2014. Acute parvovirus B19 infection led to a false positive finding of dengue fever on a rapid diagnostic test (Panbio Dengue Duo Cassette(TM)). To the best of our knowledge, there are no previous reports of a false positive result for dengue IgM with the dengue rapid diagnostic test. We believe that epidemiological information on the prevalence of parvovirus B19 is useful for guiding the interpretation of a positive result with the dengue rapid diagnostic test.

  12. A study on gender-related differences in laboratory characteristics of dengue fever.

    Science.gov (United States)

    Chakravarti, A; Roy, P; Malik, S; Siddiqui, O; Thakur, P

    2016-01-01

    Studies have reported significant gender-related differences in serological tests for detection of NS1 antigen and IgM antibody used for diagnosing dengue fever. However, no such study has been undertaken in India though dengue fever is endemic in this country. Therefore, this study was planned to study the association of serological findings with gender in 700 patients suspected to be suffering from dengue fever in the Indian setting. Haematological parameters of seropositive patients were also studied. Seropositivity and haemorrhagic findings were significantly associated with the female gender. Positive NS1 antigen and IgM antibody results were significantly associated with females and males, respectively.

  13. Dengue hemorrhagic fever: A rare cause of pituitary tumor hemorrhage and reversible vision loss

    Directory of Open Access Journals (Sweden)

    Vimal Kumar

    2011-01-01

    Full Text Available Dengue hemorrhagic fever leading to hemorrhage in pituitary adenoma is not reported till date: We herein report the first case of bilateral visual loss secondary to pituitary adenoma hemorrhage associated with dengue hemorrhagic fever. Urgent transnasal trans sphenoidal decompression of the macroadenoma prevented permanent visual loss in this patient. Pituitary apoplexy should be considered as differential diagnosis of visual deterioration apart from retinal hemorrhage, maculopathy, and optic neuropathy in cases of dengue hemorrhagic fever. Early decompression of optic nerves helped in the restoration of vision.

  14. Massive Retinal Pigment Epithelial Detachment Following Acute Hypokalemic Quadriparesis in Dengue Fever.

    Science.gov (United States)

    Goel, Neha; Bhambhwani, Vishaal; Jain, Pooja; Ghosh, Basudeb

    2016-01-01

    To describe an unusual retinal manifestation of dengue fever in an endemic region. A 35 year old male presenting with acute onset decreased vision in his right eye, was found to have a massive retinal pigment epithelial detachment (PED) extending up to the vascular arcades. He had been diagnosed with acute hypokalemic quadriparesis in dengue fever in the preceding week, which had resolved following treatment. The patient was managed conservatively. At three months follow up, there was spontaneous flattening of the PEDs with improvement in visual acuity. Dengue fever complicated by acute hypokalemic quadriparesis can be associated with PED, which can be large. The condition resolves spontaneously and bears a good prognosis.

  15. The dengue and dengue hemorrhagic fever epidemic in Puerto Rico, 1994-1995.

    Science.gov (United States)

    Rigau-Pérez, J G; Vorndam, A V; Clark, G G

    2001-01-01

    From June 1, 1994 to May 31, 1995 a total of 24,700 cases of dengue (7.01/1,000 population) were reported to the laboratory-based surveillance system in Puerto Rico (1991-1994, annual average: 2.55/1,000). Dengue virus 2 predominated. The earliest indicator of epidemic activity was the virus isolation rate in May 1994 (14.0% versus 5.7% average). The male-to-female ratio among cases was 1:1.1; 65.4% were younger than 30 years (the 10 to 19 year age group had the highest incidence, 11.8/1,000). At least 5,687 cases (23.0%) showed a hemorrhagic manifestation; 4,662 (18.9%) were hospitalized, and 40 died (0.2%; 10 laboratory-positive). Two cases documented by laboratory were transmitted by unusual routes--intrapartum and through a bone marrow transplant. Among 2,004 hospitalized cases reported by infection control nurses, 139 (6.9%) fulfilled the criteria for dengue hemorrhagic fever (DHF) and another 13 cases (0.6%) had dengue shock syndrome. This epidemic produced the largest number of hospitalizations, DHF cases, and deaths from any dengue epidemic in Puerto Rico. Severity did not change throughout the year. Surveillance capabilities were maintained by temporary, simplified reporting methods, none of which could be recommended as the single method of choice for surveillance; each must be used (on site, or as a service available from a reference laboratory) at the right time in the epidemic cycle. The utility of comparisons of current and previous data underscores the value of long-term surveillance. Our analysis was unable to document whether significantly increased transmission occurred more often in cities where the water supply was rationed or where the local landfill was closed.

  16. Can internet search queries be used for dengue fever surveillance in China?

    Science.gov (United States)

    Guo, Pi; Wang, Li; Zhang, Yanhong; Luo, Ganfeng; Zhang, Yanting; Deng, Changyu; Zhang, Qin; Zhang, Qingying

    2017-08-07

    China experienced an unprecedented outbreak of dengue fever in 2014, and the number of cases reached the highest level over the past 25 years. Traditional sentinel surveillance systems of dengue fever in China have an obvious drawback that the average delay from receipt to dissemination of dengue case data is roughly 1-2 weeks. In order to exploit internet search queries to timely monitor dengue fever, we analyzed data of dengue incidence and Baidu search query from 31 provinces in mainland China during the period of January 2011 to December 2014. We found that there was a strong correlation between changes in people's online health-seeking behavior and dengue fever incidence. Our study represents the first attempt demonstrating a strong temporal and spatial correlation between internet search trends and dengue epidemics nationwide in China. The findings will help the government to strengthen the capacity of traditional surveillance systems for dengue fever. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  17. Potential association of dengue hemorrhagic fever incidence and remote senses land surface temperature, Thailand, 1998.

    Science.gov (United States)

    Nitatpattana, Narong; Singhasivanon, Pratap; Kiyoshi, Honda; Andrianasolo, Haja; Yoksan, Sutee; Gonzalez, Jean-Paul; Barbazan, Philippe

    2007-05-01

    A pilot study was designed to analyze a potential association between dengue hemorrhagic fever (DHF) incidence and, temperature computed by satellite. DHF is a mosquito transmitted disease, and water vapor and humidity are known to have a positive effect on mosquito life by increasing survival time and shortening the development cycle. Among other available satellite data, Land Surface Temperature (LST) was chosen as an indicator that combined radiated earth temperature and atmospheric water vapor concentration. Monthly DHF incidence was recorded by province during the 1998 epidemic and obtained as a weekly combined report available from the National Ministry of Public Health. Conversely, LST was calculated using remotely sensed data obtained from thermal infrared sensors of NOAA satellites and computed on a provincial scale. Out of nine selected study provinces, five (58.3%) exhibited an LST with a significant positive correlation with rainfall (p < 0.05). In four out of nineteen surveyed provinces (21.3%), LST showed a significant positive correlation with DHF incidence (p < 0.05). Positive association between LST and DHF incidence was significantly correlated in 75% of the cases during non-epidemic months, while no correlation was found during epidemic months. Non-climatic factors are supposed to be at the origin of this discrepancy between seasonality in climate (LST) and DHF incidence during epidemics.

  18. Factors influencing dengue virus isolation by C6/36 cell culture and mosquito inoculation of nested PCR-positive clinical samples.

    Science.gov (United States)

    Jarman, Richard G; Nisalak, Ananda; Anderson, Kathryn B; Klungthong, Chonticha; Thaisomboonsuk, Butsaya; Kaneechit, Winai; Kalayanarooj, Siripen; Gibbons, Robert V

    2011-02-01

    Dengue viral isolation is necessary for definitive diagnosis, pathogenesis and evolutionary research, vaccine candidates, and diagnostic materials. Using standardized techniques, we analyzed isolation rates of 1,544 randomly selected polymerase chain reaction (PCR)-positive samples, representing all four dengue serotypes, from patients with serologically confirmed dengue infections and evaluated whether clinical and laboratory results could be predictive of isolation using standard and mosquito isolation techniques. Viruses were isolated from 62.5% of the samples by direct application to C6/36 cells and increased to 79.4% when amplifying C6/36 negative samples by intrathorasic inoculation in Toxyrhynchites splendens mosquitoes. High viremia, measured by reverse transcriptase (RT)-PCR, was a strong predictor for viral isolation by either method. Isolation was most successful in samples collected early in the disease, had low antibody levels, temperatures greater than 38°C, and had a final clinical diagnosis of dengue fever. Dengue serotypes also played a role in the success of viral isolation.

  19. Dengue and the risk of urban yellow fever reintroduction in São Paulo State, Brazil Dengue e risco da reintrodução da febre amarela urbana no Estado de São Paulo

    Directory of Open Access Journals (Sweden)

    Eduardo Massad

    2003-08-01

    Full Text Available OBJECTIVE: To propose a mathematical method for the estimation of the Basic Reproduction Number, R0, of urban yellow fever in a dengue-infested area. METHODS: The method is based on the assumption that, as the same vector (Aedes aegypti causes both infections, all the quantities related to the mosquito, estimated from the initial phase of dengue epidemic, could be applied to yellow fever dynamics. It is demonstrated that R0 for yellow fever is, on average, 43% lower than that for dengue. This difference is due to the longer dengue viremia and its shorter extrinsic incubation period. RESULTS: In this study the analysis was expanded to the epidemiological situation of dengue in São Paulo in the year 2001. The total number of dengue cases increased from 3,582 in 2000 to 51,348 in 2001. It was then calculated R0 for yellow fever for every city which have shown R0 of dengue greater than 1. It was also estimated the total number of unprotected people living in highly risky areas for urban yellow fever. CONCLUSIONS: Currently there is a great number of non-vaccinated people living in Aedes aegypti infested area in the state of São Paulo.OBJETIVO: Propor um modelo matemático para a estimativa da reprodutibilidade basal, R0, para a febre amarela urbana em uma área infestada pela dengue. MÉTODOS: O método utilizado considera que, como ambas as doenças são transmitidas pelo mesmo vetor (Aedes aegypti, poder-se-ia aplicar todos os parâmetros quantitativos relativos ao mosquito, estimados pela fase inicial da curva de crescimento de casos de dengue, à dinâmica da febre amarela. Demonstra-se que o R0 da febre amarela é em média 43% menor que o da dengue. Esta diferença deve-se à viremia mais prolongada da dengue, bem como ao menor período de incubação extrínseco daquele vírus no mosquito. RESULTADOS: Apresenta-se a aplicação desta análise matemática à situação epidemiológica da dengue no estado de São Paulo, para o ano de 2001

  20. Dengue fever in Pakistan: a paradigm shift; changing epidemiology and clinical patterns.

    Science.gov (United States)

    Haider, Zahra; Ahmad, Farina Zia; Mahmood, Asif; Waseem, Tariq; Shafiq, Irfan; Raza, Tanzeem; Qazi, Javaria; Siddique, Nasir; Humayun, Malik Asif

    2015-11-01

    Dengue fever has huge public health implications and affects over 100 million people worldwide. This review pictures the current situation of Dengue in Pakistan and presents a review of published literature. Pakistan has seen recurrent epidemics of Dengue Fever recently. Unfortunately, these epidemics are becoming more severe in their clinical manifestation. Pakistan experienced large epidemics of dengue fever during 2008, 2010 and 2011 affecting thousands of people and claiming hundreds of deaths. A comparison of data during these epidemics indicates a shift from mild to a more severe disease, which could be interpreted as an epidemiologic transition pattern in the country. Expansion of Dengue in Pakistan seems to be multifactorial, including the climate change, frequent natural disasters, vector resistance to insecticides and lack of resources. This highlights the need for rigorous vector control. Continuing education of primary care physicians is crucial for early appropriate management to reduce mortality.

  1. Wolbachia and dengue virus infection in the mosquito Aedes fluviatilis (Diptera: Culicidae).

    Science.gov (United States)

    Silva, Jéssica Barreto Lopes; Magalhães Alves, Debora; Bottino-Rojas, Vanessa; Pereira, Thiago Nunes; Sorgine, Marcos Henrique Ferreira; Caragata, Eric Pearce; Moreira, Luciano Andrade

    2017-01-01

    Dengue represents a serious threat to human health, with billions of people living at risk of the disease. Wolbachia pipientis is a bacterial endosymbiont common to many insect species. Wolbachia transinfections in mosquito disease vectors have great value for disease control given the bacterium's ability to spread into wild mosquito populations, and to interfere with infections of pathogens, such as dengue virus. Aedes fluviatilis is a mosquito with a widespread distribution in Latin America, but its status as a dengue vector has not been clarified. Ae. fluviatilis is also naturally infected by the wFlu Wolbachia strain, which has been demonstrated to enhance infection with the avian malarial parasite Plasmodium gallinaceum. We performed experimental infections of Ae. fluviatilis with DENV-2 and DENV-3 isolates from Brazil via injection or oral feeding to provide insight into its competence for the virus. We also examined the effect of the native Wolbachia infection on the virus using a mosquito line where the wFlu infection had been cleared by antibiotic treatment. Through RT-qPCR, we observed that Ae. fluviatilis could become infected with both viruses via either method of infection, although at a lower rate than Aedes aegypti, the primary dengue vector. We then detected DENV-2 and DENV-3 in the saliva of injected mosquitoes, and observed that injection of DENV-3-infected saliva produced subsequent infections in naïve Ae. aegypti. However, across our data we observed no difference in prevalence of infection and viral load between Wolbachia-infected and -uninfected mosquitoes, suggesting that there is no effect of wFlu on dengue virus. Our results highlight that Ae. fluviatilis could potentially serve as a dengue vector under the right circumstances, although further testing is required to determine if this occurs in the field.

  2. Modeled Forecasts of Dengue Fever in San Juan, Puerto Rico Using NASA Satellite Enhanced Weather Forecasts

    Science.gov (United States)

    Morin, C.; Quattrochi, D. A.; Zavodsky, B.; Case, J.

    2015-12-01

    Dengue fever (DF) is an important mosquito transmitted disease that is strongly influenced by meteorological and environmental conditions. Recent research has focused on forecasting DF case numbers based on meteorological data. However, these forecasting tools have generally relied on empirical models that require long DF time series to train. Additionally, their accuracy has been tested retrospectively, using past meteorological data. Consequently, the operational utility of the forecasts are still in question because the error associated with weather and climate forecasts are not reflected in the results. Using up-to-date weekly dengue case numbers for model parameterization and weather forecast data as meteorological input, we produced weekly forecasts of DF cases in San Juan, Puerto Rico. Each week, the past weeks' case counts were used to re-parameterize a process-based DF model driven with updated weather forecast data to generate forecasts of DF case numbers. Real-time weather forecast data was produced using the Weather Research and Forecasting (WRF) numerical weather prediction (NWP) system enhanced using additional high-resolution NASA satellite data. This methodology was conducted in a weekly iterative process with each DF forecast being evaluated using county-level DF cases reported by the Puerto Rico Department of Health. The one week DF forecasts were accurate especially considering the two sources of model error. First, weather forecasts were sometimes inaccurate and generally produced lower than observed temperatures. Second, the DF model was often overly influenced by the previous weeks DF case numbers, though this phenomenon could be lessened by increasing the number of simulations included in the forecast. Although these results are promising, we would like to develop a methodology to produce longer range forecasts so that public health workers can better prepare for dengue epidemics.

  3. Evaluation of Pyrethrin Formulations on Dengue/Dengue Haemorrhagic Fever Vectors in the Laboratory and Sublethal Effects

    Directory of Open Access Journals (Sweden)

    S Sulaiman

    2007-12-01

    Full Text Available In Southeast Asia, Aedes aegypti (L. has been incriminated as principal vector of dengue viruses and Ae. albopictus as the secondary vector of dengue fever. Therefore, the aim of this study was to investigate the effectiveness of three for-mula¬tions of pyrethrin derived from Tanacetum cinerariaefolium against the dengue/dengue haemorrhagic fever vectors Aedes aegypti and Ae. albopictus in the laboratory. The testings employed 2 methodologies: the WHO Larval Bioassay and WHO Adult Bioassay. The results showed that all the three pyrethrin formulations had larvicidal and adulticidal activi-ties. The impact of the sublethal doses of pyrethrin formulations on Aedes spp. larvae resulted in 4-6% of alive adult emergence compared to 90% of Ae. aegypti emerging adults and 96% Ae. albopictus alive adult emergence in the control. The impact of sublethal doses of the pyrethrin formulations caused very low fecundity on both Aedes spp. compared to the control (P< 0.05.

  4. Aedes aegypti (Diptera: Culicidae) Longevity and Differential Emergence of Dengue Fever in Two Cities in Sonora, Mexico.

    Science.gov (United States)

    Ernst, Kacey C; Walker, Kathleen R; Reyes-Castro, Pablo; Joy, Teresa K; Castro-Luque, A Lucia; Diaz-Caravantes, Rolando E; Gameros, Mercedes; Haenchen, Steven; Hayden, Mary H; Monaghan, Andrew; Jeffrey-Guttierez, Eileen; Carrière, Yves; Riehle, Michael R

    2017-01-01

    Dengue virus, primarily transmitted by the Aedes aegypti (L.) mosquito, has rapidly expanded in geographic extent over the past several decades. In some areas, however, dengue fever has not emerged despite established Ae. aegypti populations. The reasons for this are unclear and have sometimes been attributed to socio-economic differences. In 2013 we compared Ae. aegypti adult density and population age structure between two cities in Sonora, Mexico: Hermosillo, which has regular seasonal dengue virus transmission, and Nogales, which has minimal transmission. Larval and pupal abundance was greater in Nogales, and adult density was only higher in Hermosillo during September. Population age structure, however, was consistently older in Hermosillo. This difference in longevity may have been one factor that limited dengue virus transmission in Nogales in 2013, as a smaller proportion of Ae. aegypti females survived past the extrinsic incubation period. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  5. A CLINICAL EXPERIENCE OF USING EXTRACORPOREAL CYTOKINE ADSORPTION DEVICE (CYTOSORB ® IN A CASE OF DENGUE FEVER

    Directory of Open Access Journals (Sweden)

    Zafer A. Khan

    2016-10-01

    Full Text Available BACKGROUND Dengue is a mosquito-borne viral disease transmitted by Aedes aegypti and Aedes albopictus. It is hypothesised that elevated cytokines such as tumour necrosis factor alpha (TNF-α, interleukins and interferon gamma (IFN-γ during severe dengue causes damage to the endothelial cells of the capillaries that results in fluid leakage. A novel Extracorporeal Cytokine Adsorption Device (ECAD CytoSorb ® targets the cytokines helps modulate immune response and prevent multiorgan dysfunction syndrome. MATERIALS AND METHODS We report a case of dengue fever with septic shock and multiorgan failure admitted in the intensive care. He was treated with standard of care along with mechanical ventilation and renal replacement therapy. A novel ECAD CytoSorb was used as an adjuvant supportive therapy. The patient also received multiple transfusions to address thrombocytopenia and coagulopathy. RESULTS The patient showed gradual improvement. The patient showed normalised central nervous system function, improved oxygenation status, adequate renal function and normal platelet count at the time of discharge. The liver function had also improved significantly. CONCLUSION Extracorporeal Cytokine Adsorption device CytoSorb ® might be useful option as an adjuvant therapy in dengue patients with MODS.

  6. Modelling spatial connectivity in epidemiological systems, dengue fever in Thailand on networks from radiation models

    Science.gov (United States)

    Stollenwerk, Nico; Götz, Thomas; Mateus, Luis; Wijaya, Putra; Willems, David; Skwara, Urszula; Marguta, Ramona; Ghaffari, Peyman; Aguiar, Maíra

    2016-06-01

    We model the connectivity between Thai provinces in terms of human mobility via a radiation model in order to describe dengue fever spreading in Thailand, for which long term epidemiological data are available.

  7. A probabilistic risk assessment for dengue fever by a threshold based-quantile regression

    Science.gov (United States)

    Chiu, Chuan-Hung; Tan, Yih-Chi; Wen, Tzai-Hung; Chien, Lung-Chang; Yu, Hwa-Lung

    2014-05-01

    This article introduces an important concept "return period" to analyze potential incident rate of dengue fever by bringing together two models: the quantile regression model and the threshold-based method. The return period provided the frequency of incidence of dengue fever, and established the risk maps for potential incidence of dengue fever to point out highest risk in certain areas. A threshold-based linear quantile regression model was constructed to find significantly main effects and interactions based on collinearity test and stepwise selection, and also showed the performance of our model via pseudo R2. Finally, the spatial risk maps of the specified return periods and average incident rates were given, and indicated that high population density place (e.g., residential area), water conservancy facilities, and corresponding interactions could lead to a positive influence on dengue fever. These factors would be the key point to disease protection in a given study area.

  8. Acute Compressive Ulnar Neuropathy in a Patient of Dengue Fever: An Unusual Presentation

    Directory of Open Access Journals (Sweden)

    Anil K Mehtani

    2013-04-01

    Full Text Available Introduction: Dengue haemorrhagic fever is known for its haemorrhagic and neurologic complications. Neurologic complications are caused by three mechanism namely neurotropism, systemic complications causing encephalopathy and postinfectious immune-mediated mechanisms. However acute compressive neuropathy due to haemorrhage is not frequent and we could find no literature describing this Case Report: We report a case of acute compressive ulnar neuropathy due to peri neural hematoma, following an attempt at intravenous cannulation in the cubital fossa in a patient of dengue haemorrhagic fever with thrombocytopenia. Immediate fasciotomy and removal of haematoma was performed to relieve the symptoms. Conclusion: Compression neuropathies can be seen in dengue hemorrhagic fever and removal of compressing hematoma relieves symptoms. Keywords: Dengue haemmorrhagic fever; coagulopathy; peri neural haematoma.

  9. Exploratory Analysis of Dengue Fever Niche Variables within the Río Magdalena Watershed

    Directory of Open Access Journals (Sweden)

    Austin Stanforth

    2016-09-01

    Full Text Available Previous research on Dengue Fever have involved laboratory tests or study areas with less diverse temperature and elevation ranges than is found in Colombia; therefore, preliminary research was needed to identify location specific attributes of Dengue Fever transmission. Environmental variables derived from the Moderate Resolution Imaging Spectroradiometer (MODIS and Tropical Rainfall Measuring Mission (TRMM satellites were combined with population variables to be statistically compared against reported cases of Dengue Fever in the Río Magdalena watershed, Colombia. Three-factor analysis models were investigated to analyze variable patterns, including a population, population density, and empirical Bayesian estimation model. Results identified varying levels of Dengue Fever transmission risk, and environmental characteristics which support, and advance, the research literature. Multiple temperature metrics, elevation, and vegetation composition were among the more contributory variables found to identify future potential outbreak locations.

  10. [An Experience Promoting the Interdisciplinary Care Model for Dengue Fever].

    Science.gov (United States)

    Kuo, Wen-Fu; Ke, Ya-Ting

    2016-08-01

    Emergency departments represent the first line in facing major healthcare events. During major epidemic outbreaks, patients crowding into the emergency departments increase the wait time for patients and overload the staffs that are on duty. The dengue fever outbreak in southern Taiwan during the summer 2015 presented a huge management challenge for physicians and nurses in local hospitals. We responded to this challenge by integrating resources from different hospital departments. This strategy successfully increased group cohesiveness among the medical team, ensuring that they could not only ultimately cope with the outbreak together but also effectively provide patient-centered care. This interdisciplinary care model may serve as a reference for medical professionals for the management of future epidemics and similar events.

  11. Issues Related to Recent Dengue Vaccine Development

    OpenAIRE

    Konishi, Eiji

    2011-01-01

    Dengue fever (DF) and dengue hemorrhagic fever (DHF) are mosquito-transmitted diseases of global importance. Despite significant research efforts, no approved vaccines or antiviral drugs against these diseases are currently available. This brief article reviews the status of dengue vaccine development, with particular emphasis on the vaccine strategies in more advanced stages of evaluation; these include traditional attenuation, chimerization and engineered attenuation. Several aspects of the...

  12. Early warning signal for dengue outbreaks and identification of high risk areas for dengue fever in Colombia using climate and non-climate datasets.

    Science.gov (United States)

    Lee, Jung-Seok; Carabali, Mabel; Lim, Jacqueline K; Herrera, Victor M; Park, Il-Yeon; Villar, Luis; Farlow, Andrew

    2017-07-10

    Dengue has been prevalent in Colombia with high risk of outbreaks in various locations. While the prediction of dengue epidemics will bring significant benefits to the society, accurate forecasts have been a challenge. Given competing health demands in Colombia, it is critical to consider the effective use of the limited healthcare resources by identifying high risk areas for dengue fever. The Climate Risk Factor (CRF) index was constructed based upon temperature, precipitation, and humidity. Considering the conditions necessary for vector survival and transmission behavior, elevation and population density were taken into account. An Early Warning Signal (EWS) model was developed by estimating the elasticity of the climate risk factor function to detect dengue epidemics. The climate risk factor index was further estimated at the smaller geographical unit (5 km by 5 km resolution) to identify populations at high risk. From January 2007 to December 2015, the Early Warning Signal model successfully detected 75% of the total number of outbreaks 1 ~ 5 months ahead of time, 12.5% in the same month, and missed 12.5% of all outbreaks. The climate risk factors showed that populations at high risk are concentrated in the Western part of Colombia where more suitable climate conditions for vector mosquitoes and the high population level were observed compared to the East. This study concludes that it is possible to detect dengue outbreaks ahead of time and identify populations at high risk for various disease prevention activities based upon observed climate and non-climate information. The study outcomes can be used to minimize potential societal losses by prioritizing limited healthcare services and resources, as well as by conducting vector control activities prior to experiencing epidemics.

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

    Science.gov (United States)

    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.

  14. Role of platelet transfusion in children with bleeding in dengue fever

    OpenAIRE

    Sriram Pothapregada; Banupriya Kamalakannan; Mahalakshmy Thulasingam

    2015-01-01

    Background & objectives: The indications for platelet transfusion in dengue fever are clearly defined in World Health Organization (WHO) guidelines (2011) for dengue fever, but physicians face practical difficulty in its implementation in an epidemic setting. On one hand there is an intense social pressure created by the panic-struck parents to transfuse platelets in presence of bleeding and on the other hand there is a need for its judicious use as the requirement is more than its availabili...

  15. Invasive pulmonary aspergillosis in an immunocompetent patient with severe dengue fever.

    Science.gov (United States)

    Nasa, Prashant; Yadav, Rohit; Nagrani, S K; Raina, Sanjay; Gupta, Ankur; Jain, Shakti

    2014-05-01

    We report a case of a 65-year-old female diagnosed with sever dengue fever. She started showing recovery from dengue fever with medical management. On day 6 of admission, she had leukocytosis, altered mental sensorium, and hemoptysis. Chest tomography showed air space consolidation with multiple nodules in the left upper and middle lobe sputum and bronchoalveolar lavage cultures were positive for Aspergillus flavus. The patient showed improvement with voriconazole and therapy was continued for 6 weeks.

  16. Dengue fever triggering systemic lupus erythematosus and lupus nephritis: a case report

    Directory of Open Access Journals (Sweden)

    Talib SH

    2013-10-01

    Full Text Available SH Talib, SR Bhattu, R Bhattu, SG Deshpande, DB Dahiphale Department of Medicine and Nephrology, MGM Medical College and Hospital, Aurangabad, Maharashtra, India Abstract: We report a rare case of dengue fever triggering systemic lupus erythematosus and lupus nephritis. The patient presented herself during a large outbreak of dengue fever in December 2012 in Maharashtra, India. The diagnosis of dengue fever was confirmed by the presence of NS-1 antigen during the first few days of febrile illness. Eight weeks later, kidney tissue biopsy studies revealed evidence of lupus nephritis on microscopic examination and immunofluorescence. The report interpreted it as focal proliferative glomerulonephritis and segmental sclerosis (Stage IIIC. The case was also found positive for perinuclear antineutrophil cytoplasmic antibodies by indirect immunofluorescence assay. An active and effective management of a case essentially calls for clear perception of differentiating dengue-induced lupus flare, antineutrophil cytoplasmic antibody-related nephropathy, and/or dengue-induced de-novo lupus disease. Dengue viremia may be the trigger for immune complex formation in patients who are predisposed to developing autoimmune diseases. The present case explains the importance of considering the diagnosis of dengue-related lupus nephritis as an atypical occurrence in appropriate situations, as in this case. It would not be improper to regard this escalating disease as an expanded feature of dengue. Keywords: kidney biopsy, glomerulonephritis, segmental sclerosis, lupus flare, dengue viremia, autoimmune, de-novo lupus nephritis

  17. Factors affecting dengue fever knowledge, attitudes and practices among selected urban, semi-urban and rural communities in Malaysia.

    Science.gov (United States)

    Al-Dubai, Sami Abdo Radman; Ganasegeran, Kurubaran; Mohanad Rahman, Alwan; Alshagga, Mustafa Ahmed; Saif-Ali, Riyadh

    2013-01-01

    Dengue fever is a major public health problem in Malaysia. This study aimed to assess factors affecting knowledge, attitudes, and practices regarding dengue fever among a selected population in Malaysia. A descriptive, community-based, cross sectional study was conducted with 300 participants from three different geographical settings in urban, semi-urban, and rural areas within the states of Selangor and Kuala Lumpur. The questionnaire included questions on demographic data, knowledge, attitudes, and practices regarding dengue fever. Mean age of respondents was 34.4 (+/- 5.7) years, and the age ranged from 18 to 65 years. The majority of respondents were married (54.7%), Malays (72.7%) and heard about dengue fever (89.7%). Television was the common source of information about dengue fever (97.0%). Participants answered 4 out of 15 items of knowledge incorrectly. There was no significant association between knowledge score and socio-demographic factors. About one-fifth of the respondents (24%) believed that immediate treatment is not necessary for dengue fever, and the majority of them were not afraid of the disease (96.0%). Attitudes toward dengue fever were significantly associated with the level of education and employment status (p dengue fever (p = 0.030). There is a need to increase health promotion activities through campaigns and social mobilization to increase knowledge regarding dengue fever. This would help to mold positive attitudes and cultivate better preventive practices among the public to eliminate dengue in the country.

  18. Challenges in dengue fever in the elderly: atypical presentation and risk of severe dengue and hospital-acquired infection [corrected].

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    Emily K Rowe

    2014-04-01

    Full Text Available BACKGROUND/METHODS: To better understand dengue fever in the elderly, we compared clinical features, World Health Organization (WHO dengue classification and outcomes between adult (<60 and elderly (≥60 dengue patients. We explored the impact of co-morbidity and hospital-acquired infection (HAI on clinical outcomes in the elderly. All patients managed at the Communicable Disease Centre, Singapore, between 2005 and 2008 with positive dengue polymerase chain reaction (PCR or who fulfilled WHO 1997 or 2009 probable dengue criteria with positive dengue IgM were included. RESULTS: Of the 6989 cases, 295 (4.4% were elderly. PCR was positive in 29%. The elderly suffered more severe disease with more dengue haemorrhagic fever (DHF (29.2% vs. 21.4% and severe dengue (SD (20.3% vs. 14.6% (p<0.05. Classic dengue symptoms were more common in the adult group. The elderly were less likely to fulfill WHO 1997 (93.6% vs. 96.4% (p = 0.014, but not WHO 2009 probable dengue (75.3% vs. 71.5%. Time to dengue diagnosis was similar. There was no significant difference in the frequency of warning signs between the two groups, but the elderly were more likely to have hepatomegaly (p = 0.006 and malaise/lethargy (p = 0.033 while the adults had significantly more mucosal bleeding (p<0.001. Intensive care admission occurred in 15 and death in three, with no age difference. Notably, the elderly stayed in hospital longer (median 5 vs. 4 days, and suffered more pneumonia (3.8% vs. 0.7% and urinary infection (1.9% vs. 0.3% (p = 0.003. Predictors of excess length of stay were age (adjusted odds ratio [aOR] 2.01, 95% confidence interval [CI] 1.37-2.88, critical illness (aOR 5.13, 95%CI 2.59-9.75, HAI (aOR 12.06, 95%CI 7.39-19.9, Charlson score (aOR 6.9, 95%CI 2.02-22.56 and severe dengue (DHF/dengue shock syndrome/SD (aOR 2.24, 95%CI 1.83-2.74. CONCLUSION: Elderly dengue patients present atypically and are at higher risk of DHF, SD and HAI. Aside from dengue

  19. Scanning electron microscopy of the four larval instars of the Dengue fever vector Aedes aegypti (Diptera: Culicidae

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    Stefan Schaper

    2006-09-01

    Full Text Available Aedes aegypti is the main insect vector of Dengue fever and dengue hemorrhagic fever/dengue shock syndrome and represents the only vulnerable element in the control of this disease. Therefore, the identification and quantification of this mosquito is an important task; however, the majority of taxonomic keys are based on the 4th larval instar. For that reason, this study describes the four larval instars of A. aegypti using scanning electron microscopy. Morphological changes during larval development were observed at the pecten, comb scales and the ventral brush of the abdominal segment X; however, the 3rd and 4th instars showed similar structures with only a slight variation. The structures described in this study will be helpful in the identification of the four instars of A. aegypti, a fundamental task for comprehending the natural history of dengue mainly in new territories affected. Rev. Biol. Trop. 54 (3: 847-852. Epub 2006 Sept. 29.Aedes aegypti es el principal insecto vector de la fiebre del dengue y del dengue hemorrágico/síndrome del choque por dengue y es el único elemento atacable para el control de esta virosis. La identificación y cuantificación de éste es una tarea importante; no obstante, la mayoría de las llaves taxonómicas se basan en el cuarto estadio larval. Por esta razón, en este trabajo se describen los cuatro estadios larvales de A. aegypti los cuales fueron examinados mediante microscopia electrónica de rastreo. Los cambios morfológicos ocurridos durante el desarrollo larval fueron observados en el pecten, las escamas del peine, el cepillo ventral del décimo segmento. El 3ero y 4to estadios larvales mostraron estructuras similares con sólo ligeras variaciones. Las estructuras descritas en este artículo permiten identificar cualquiera de los cuatro estadios larvales de A. aegypti, lo cual representa una tarea importante en la comprensión de la historia natural del dengue en los nuevos territorios afectados.

  20. Patterns of Gall Bladder Wall Thickening in Dengue Fever: A Mirror of the Severity of Disease.

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    Parmar, Jitendra Premjibhai; Mohan, Chander; Vora, Maulik

    2017-04-01

    Dengue fever is a major public health problem with an increased incidence in recent years. Gall bladder wall thickening has been reported as one of the most common findings in dengue fever. There is a paucity of literature regarding the various patterns of gall bladder wall thickening in dengue fever and their significance in predicting the severity of disease. Out of 93 seropositive patients included in the study, 54 patients with dengue fever had gall bladder wall thickening. 4 patterns of gall bladder wall thickening are demonstrated in this study. A uniform echogenic pattern in 20 patients, striated or tram track pattern in 11 patients, an asymmetric pattern in 2 patients and a honeycombing pattern in 21 patients. The range of patterns of wall thickening included normal wall thickening or uniform echogenic wall thickening in DF without warning signs, a striated or tram track pattern, and a honeycomb pattern in severe DF. Serial ultrasound done on consecutive alternate days revealed a change in the pattern of gall bladder wall thickening according to the severity of disease. The present study revealed 4 distinct patterns of gall bladder wall thickening. The uniform echogenic pattern was found to be more prevalent in dengue fever without warning signs, while the honeycomb pattern was found to be more prevalent in severe dengue fever. A change in the pattern of gall bladder wall thickening on subsequent serial ultrasound can predict the severity of the disease.

  1. Risk assessment of dengue fever in Zhongshan, China: a time-series regression tree analysis.

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    Liu, K-K; Wang, T; Huang, X-D; Wang, G-L; Xia, Y; Zhang, Y-T; Jing, Q-L; Huang, J-W; Liu, X-X; Lu, J-H; Hu, W-B

    2017-02-01

    Dengue fever (DF) is the most prevalent and rapidly spreading mosquito-borne disease globally. Control of DF is limited by barriers to vector control and integrated management approaches. This study aimed to explore the potential risk factors for autochthonous DF transmission and to estimate the threshold effects of high-order interactions among risk factors. A time-series regression tree model was applied to estimate the hierarchical relationship between reported autochthonous DF cases and the potential risk factors including the timeliness of DF surveillance systems (median time interval between symptom onset date and diagnosis date, MTIOD), mosquito density, imported cases and meteorological factors in Zhongshan, China from 2001 to 2013. We found that MTIOD was the most influential factor in autochthonous DF transmission. Monthly autochthonous DF incidence rate increased by 36·02-fold [relative risk (RR) 36·02, 95% confidence interval (CI) 25·26-46·78, compared to the average DF incidence rate during the study period] when the 2-month lagged moving average of MTIOD was >4·15 days and the 3-month lagged moving average of the mean Breteau Index (BI) was ⩾16·57. If the 2-month lagged moving average MTIOD was between 1·11 and 4·15 days and the monthly maximum diurnal temperature range at a lag of 1 month was <9·6 °C, the monthly mean autochthonous DF incidence rate increased by 14·67-fold (RR 14·67, 95% CI 8·84-20·51, compared to the average DF incidence rate during the study period). This study demonstrates that the timeliness of DF surveillance systems, mosquito density and diurnal temperature range play critical roles in the autochthonous DF transmission in Zhongshan. Better assessment and prediction of the risk of DF transmission is beneficial for establishing scientific strategies for DF early warning surveillance and control.

  2. Recombinant Production of the Amino Terminal Cytoplasmic Region of Dengue Virus Non-Structural Protein 4A for Structural Studies

    OpenAIRE

    Yu-Fu Hung; Olga Valdau; Sven Schünke; Omer Stern; Koenig, Bernd W.; Dieter Willbold; Silke Hoffmann

    2014-01-01

    BACKGROUND: Dengue virus (DENV) is a mosquito-transmitted positive single strand RNA virus belonging to the Flaviviridae family. DENV causes dengue fever, currently the world's fastest-spreading tropical disease. Severe forms of the disease like dengue hemorrhagic fever and dengue shock syndrome are life-threatening. There is no specific treatment and no anti-DENV vaccines. Our recent data suggests that the amino terminal cytoplasmic region of the dengue virus non-structural protein 4A (NS4A)...

  3. Pathologic highlights of dengue hemorrhagic fever in 13 autopsy cases from Myanmar.

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    Aye, Khin Saw; Charngkaew, Komgrid; Win, Ne; Wai, Kyaw Zin; Moe, Kyaw; Punyadee, Nuntaya; Thiemmeca, Somchai; Suttitheptumrong, Aroonroong; Sukpanichnant, Sanya; Prida, Malasit; Halstead, Scott B

    2014-06-01

    Vascular permeability, thrombocytopenia, liver pathology, complement activation, and altered hemostasis accompanying a febrile disease are the hallmarks of the dengue hemorrhagic fever/dengue shock syndrome, a major arthropod-borne viral disease that causes significant morbidity and mortality throughout tropical countries. We studied tissues from 13 children who died of acute dengue hemorrhagic fever/dengue shock syndrome at the Childrens' Hospital, Yangon, Myanmar. Dengue viral RNA from each of the 4 dengue viruses (DENVs) was detected by reverse transcriptase polymerase chain reaction in 11 cases, and dengue viral proteins (envelope, NS1, or NS3) were detected in 1 or more tissues from all 13 cases. Formalin-fixed and frozen tissues were studied for evidence of virus infection using monoclonal antibodies against DENV structural and nonstructural antigens (E, NS1, and nonsecreting NS3). In the liver, DENV infection occurred in hepatocytes and Kupffer cells but not in endothelial cells. Liver damage was associated with deposition on hepatocytes of complement components of both classical and alternative pathways. Evidence of dengue viral replication was observed in macrophage-like cells in spleens and lymph nodes. No dengue antigens were detected in endothelial cells in any organ. Germinal centers of the spleen and lymph nodes showed a marked reduction in the number of lymphocytes that were replaced by eosinophilic deposits, which contained dengue antigens as well as immunoglobulins, and complement components (C3, C1q, and C9). The latter findings had previously been reported but overlooked as a diagnostic feature.

  4. CLINICAL PROFILE OF DENGUE HAEMORRHAGIC FEVER FROM JAN 2009 TO DEC 2009 IN AND AROUND AURANGABAD

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    Duthade Mangala

    2013-11-01

    Full Text Available ABSTRACT: In present study 890 serum samples of patients suspected of dengue fever on clinical grounds were received in department of Microbiology. Out of these 249 cases showed thrombocytopenia (platelet count <1 lakh /cumm and were subjected to rapid dengue serological test as well as IgM capture ELISA. 11/ 249 (4% cases were diagnosed as primary dengue infection (only IgM positive by rapid dengue IgG/IgM bispot immunocomb test. There were 123(49% cases with only IgG positive suggesting secondary/past dengue infection. Both IgM and IgG were positive in 24(10% cases. Number of cases negative for both IgM and IgG were 91(37%. IgM positive cases were confirmed by IgM capture ELISA. Classical dengue fever (DF was noted in 168 (67% patients and dengue hemorrhagic fever (DHF in 81(33% cases. Common clinical presentations of DHF were fever 78(96%, body - ache 74(91%, arthralgia 74 (91%, retro - orbital pain 65(80%, abdominal pain 07(09%. Bleeding manifestation were in the form of petechiae, melena, epistaxis, hematuria, hemoptysis, hematemesis, bleeding gums and conjunctival hemorrhages. Out of 81 Dengue haemorrhagic fever (DHF patients 13(16% patients had platelet count between 50,000 and 1 lakh. 68(84% patients had platelet count below 50,000. Majority of these patients 47(58% had platelet below 20000 and were IgG posit ive. Thrombocytopenia correlated well with bleeding manifestations in our patients. In an epidemic setting if the patients present with fever, vomiting, musculoskeletal pain and bleeding along with low platelet count a strong possibility of DHF/ Dengu e shock syndrome (DSS should be kept in mind

  5. Spatiotemporal analysis of dengue fever in Nepal from 2010 to 2014.

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    Acharya, Bipin Kumar; Cao, ChunXiang; Lakes, Tobia; Chen, Wei; Naeem, Shahid

    2016-08-22

    Due to recent emergence, dengue is becoming one of the major public health problems in Nepal. The numbers of reported dengue cases in general and the area with reported dengue cases are both continuously increasing in recent years. However, spatiotemporal patterns and clusters of dengue have not been investigated yet. This study aims to fill this gap by analyzing spatiotemporal patterns based on monthly surveillance data aggregated at district. Dengue cases from 2010 to 2014 at district level were collected from the Nepal government's health and mapping agencies respectively. GeoDa software was used to map crude incidence, excess hazard and spatially smoothed incidence. Cluster analysis was performed in SaTScan software to explore spatiotemporal clusters of dengue during the above-mentioned time period. Spatiotemporal distribution of dengue fever in Nepal from 2010 to 2014 was mapped at district level in terms of crude incidence, excess risk and spatially smoothed incidence. Results show that the distribution of dengue fever was not random but clustered in space and time. Chitwan district was identified as the most likely cluster and Jhapa district was the first secondary cluster in both spatial and spatiotemporal scan. July to September of 2010 was identified as a significant temporal cluster. This study assessed and mapped for the first time the spatiotemporal pattern of dengue fever in Nepal. Two districts namely Chitwan and Jhapa were found highly affected by dengue fever. The current study also demonstrated the importance of geospatial approach in epidemiological research. The initial result on dengue patterns and risk of this study may assist institutions and policy makers to develop better preventive strategies.

  6. Synthesis and characterization of silver nanoparticles using Gmelina asiatica leaf extract against filariasis, dengue, and malaria vector mosquitoes.

    Science.gov (United States)

    Muthukumaran, Udaiyan; Govindarajan, Marimuthu; Rajeswary, Mohan; Hoti, S L

    2015-05-01

    Mosquitoes are blood-feeding insects and serve as the most important vectors for spreading human diseases such as malaria, yellow fever, dengue fever, and filariasis. The continued use of synthetic insecticides has resulted in resistance in mosquitoes. Synthetic insecticides are toxic and affect the environment by contaminating soil, water, and air, and then natural products may be an alternative to synthetic insecticides because they are effective, biodegradable, eco-friendly, and safe to environment. Botanical origin may serve as suitable alternative biocontrol techniques in the future. The present study was carried out to establish the larvicidal potential of leaf extracts of Gmelina asiatica and synthesized silver nanoparticles using aqueous leaf extract against late third instar larvae of Anopheles stephensi, Aedes aegypti, and Culex quinquefasciatus. Larvae were exposed to varying concentrations of plant extracts and synthesized AgNPs for 24 h. The results were recorded from UV-visible spectroscopy, Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, and energy-dispersive X-ray spectroscopy analysis support the biosynthesis and characterization of AgNPs. The maximum efficacy was observed in synthesized AgNPs against the larvae of An. stephensi (lethal dose (LC₅₀) = 22.44 μg/mL; LC₉₀ 40.65 μg/mL), Ae. aegypti (LC₅₀ = 25.77 μg/mL; LC₉₀ 45.98 μg/mL), and C. quinquefasciatus (LC₅₀ = 27.83 μg/mL; LC₉₀ 48.92 μg/mL), respectively. No mortality was observed in the control. This is the first report on mosquito larvicidal activity of plant-synthesized nanoparticles. Thus, the use of G. asiatica to synthesize silver nanoparticles is a rapid, eco-friendly, and a single-step approach and the AgNps formed can be potential mosquito larvicidal agents.

  7. Dengue fever and El Nino/Southern Oscillation in Queensland, Australia: a time series predictive model.

    Science.gov (United States)

    Hu, Wenbiao; Clements, Archie; Williams, Gail; Tong, Shilu

    2010-05-01

    It remains unclear over whether it is possible to develop an epidemic forecasting model for transmission of dengue fever in Queensland, Australia. To examine the potential impact of El Niño/Southern Oscillation on the transmission of dengue fever in Queensland, Australia and explore the possibility of developing a forecast model of dengue fever. Data on the Southern Oscillation Index (SOI), an indicator of El Niño/Southern Oscillation activity, were obtained from the Australian Bureau of Meteorology. Numbers of dengue fever cases notified and the numbers of postcode areas with dengue fever cases between January 1993 and December 2005 were obtained from the Queensland Health and relevant population data were obtained from the Australia Bureau of Statistics. A multivariate Seasonal Auto-regressive Integrated Moving Average model was developed and validated by dividing the data file into two datasets: the data from January 1993 to December 2003 were used to construct a model and those from January 2004 to December 2005 were used to validate it. A decrease in the average SOI (ie, warmer conditions) during the preceding 3-12 months was significantly associated with an increase in the monthly numbers of postcode areas with dengue fever cases (beta=-0.038; p = 0.019). Predicted values from the Seasonal Auto-regressive Integrated Moving Average model were consistent with the observed values in the validation dataset (root-mean-square percentage error: 1.93%). Climate variability is directly and/or indirectly associated with dengue transmission and the development of an SOI-based epidemic forecasting system is possible for dengue fever in Queensland, Australia.

  8. The Utilization of Standard Deviational Ellipse (SDE Model for the Analysis of Dengue Fever Cases in Banjar City 2013

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    Martya Rahmaniati

    2014-06-01

    Full Text Available Dengue Fever Disease is still regarded as an endemic disease in Banjar City. Information is still required to map dengue fever case distribution, mean center of case distribution, and the direction of dengue fever case dispersion in order to support the surveillance program in the relation to the vast area of the dengue fever disease control program. The objective of the research is to obtain information regarding the area of dengue fever disease distribution in Banjar City by utilizing the Standard Deviational Ellipse (SDE model. The research is an observational study with Explanatory Spatial Data Analysis (ESDA. Data analysis uses SDE model with the scope of the entire sub district area in Banjar City. The data analyzed is dengue fever case from 2007-2013 periods, with the number of sample of 315 cases. Social demographic overview of dengue fever patients in Banjar City shows that most of the patients are within the productive age, with 39.7% within the school age and 45.7% are within the work age. Most of the dengue fever patients are men (58.1%. Distribution of dengue fever cases from the period of 2007 until 2012 mostly occur in 25-37.5 meters above sea level (MASL (55.8%. The SDE models of dengue fever cases in Banjar City generally form dispersion patterns following the x-axis and clustered by physiographic boundaries. The SDE model can be used to discover dispersion patterns and directions of dengue fever cases, therefore, dengue fever disease control program can be conducted based on local-specific information, in order to support health decision.

  9. Prevalence of undifferentiated fever in adults of Rawalpindi having primary dengue fever.

    Science.gov (United States)

    Zafar, Humaira; Hayyat, Abbas; Akhtar, Naeem; Rizwan, Syeda Fatima

    2013-06-01

    The objectives of the study were to highlight early subclinical presentation of dengue viral infection (DVI) as an undifferentiated febrile illness. The descriptive cross-sectional study was carried out at Microbiology Department, Rawalpindi Medical College from March to September 2009. Stratified random sampling was used to select subjects from various urban and rural areas of Rawalpindi, and Serum IgG anti-dengue antibodies were detected by using 3rd generation enzyme-linked immunosorbent assay (ELISA). Out of the total 240 subjects, 69 (28.75%) were found to be positive for anti-dengue IgG antibodies. Of the positive cases, 41 (59.4%) - comprising 31 (44.9%) urban residents - and 10 (14.4%) rural residents presented with a previous history of undifferentiated fever (p<0.05). It was concluded that primary DVI can present as subclinical form in healthy population residing in rural and urban areas of Rawalpindi, which is an alarming situation indicating the spread of disease in the study area.

  10. Is excessive acetaminophen intake associated with transaminitis in adult patients with dengue fever?

    Science.gov (United States)

    Pandejpong, D; Saengsuri, P; Rattarittamrong, R; Rujipattanakul, T; Chouriyagune, C

    2015-06-01

    Dengue, an endemic infection causing severe flu-like symptoms and fever, is often treated with high-dose acetaminophen that can exceed recommended daily dosages. This leads to hepatotoxicity, although the underlying mechanism is poorly understood. We hypothesised that excessive acetaminophen causes hepatic toxicity in dengue patients. To investigate a correlation between elevated serum transaminases and excessive acetaminophen intake, and other aggravating factors of liver injury in dengue cases. This prospective observational study obtained blood samples from 150 participants with acute febrile illness for dengue serological tests, blood counts, and the detection of serum transaminases and acetaminophen levels. Other factors were determined by questionnaire. Of 150 participants enrolled, 77 had dengue fever. Abnormally high serum aspartate transaminase and alanine transaminase levels were present in 97.0% and 75.3% of dengue cases respectively. Multivariate analysis of cases with increased serum transaminases more than threefold normal upper limits indicated that male gender (odds ratio (OR) = 3.62, 95% confidence interval (CI) 1.38-9.42) and consuming >8 g acetaminophen orally (OR = 4.62, 95% CI 1.37-13.18) correlated with transaminitis. No correlation was found for other factors such as age, fever day at presentation, body mass index, alcohol intake or dengue severity classification (all P > 0.05). Chronic alcohol consumption was higher in non-dengue (2.6%) versus dengue cases (27.8%) (P dengue patients had mild-to-moderate transaminitis. Male gender and acetaminophen >8 g were associated with increased serum transaminases. Thus, 1000 mg acetaminophen every 8 h or dengue cases. Chronic alcohol consumption might be protective against dengue infection. © 2015 Royal Australasian College of Physicians.

  11. DENGUE: GLOBAL THREAT.

    Science.gov (United States)

    Thisyakorn, Usa; Thisyakorn, Chule

    2015-01-01

    Dengue is a mosquito-borne viral disease, which is currently an expanding global problem. Four closely related dengue serotypes cause the disease, which ranges from asymptomatic infection to undifferentiated fever, dengue fever (DF), and dengue hemorrhagic fever (DHF). DHF is characterized by fever, bleeding diathesis, and a tendency to develop a potentially fatal shock syndrome. Dengue infection with organ impairment mainly involves the central nervous system and the liver. Consistent hematological findings include vasculopathy, coagulopathy, and thrombocytopenia. Laboratory diagnosis includes virus isolation, serology, and detection of dengue ribonucleic acid. Successful treatment, which is mainly supportive, depends on early recognition of the disease and careful monitoring for shock. A severity-based revised dengue classification for medical interventions has been developed and validated in many countries. There is no specific dengue treatment, and prevention is currently limited to vector control measures. The world's first, large-scale dengue vaccine efficacy study demonstrated its efficacy and a reduction of dengue disease severity with a good safety profile in a study of more than 30,000 volunteers from Asia and Latin America.

  12. Bridging Epidemiology and Remote Sensing: A Case Study of Dengue Fever and Land Use and Land Cover Change in Roatán, Honduras

    Science.gov (United States)

    Tuholske, C.; Brooks, T.

    2015-12-01

    Dengue fever is one of the fastest spreading infectious diseases in Latin America and the Caribbean. As part of a yearlong epidemiological study of dengue, this paper takes the first step to model the relationship between the urban/built environment and incidents of dengue fever in Roatán, Honduras. Roatán has experienced an 80-fold increase in annual tourists since the 1990s, with over 1.2 million people now visiting the island yearly. In tandem, the Caribbean island's population has exploded from fewer than 13,000 people in the 1970s to over 100,000 people today. Using broadband remote sensed satellite imagery, this paper maps and measures how this massive influx of tourists and population has altered the island's landscape. Results from a decision tree classifying technique applied to a Landsat 5 Thematic Mapper (TM) image from 1985 and Landsat 8 Operational Land Imager (OLI) image from 2014 suggest a rapid pace of urbanization; built and impervious surface has increased over 300% in the last 30 years. Emerging research suggests, similar to other mosquito-borne diseases, a correlation between built environment and risk to dengue because of the increase in stagnate water that serve as disease-host reservoirs. This remote sensing analysis will be integrated with georeferenced household level data of cases of dengue collected during a year-long cross-sectional study of dengue patients in Roatán. The result will be to model the relationship between dengue fever and urban/built environment.

  13. Mining local climate data to assess spatiotemporal dengue fever epidemic patterns in French Guiana.

    Science.gov (United States)

    Flamand, Claude; Fabregue, Mickael; Bringay, Sandra; Ardillon, Vanessa; Quénel, Philippe; Desenclos, Jean-Claude; Teisseire, Maguelonne

    2014-10-01

    To identify local meteorological drivers of dengue fever in French Guiana, we applied an original data mining method to the available epidemiological and climatic data. Through this work, we also assessed the contribution of the data mining method to the understanding of factors associated with the dissemination of infectious diseases and their spatiotemporal spread. We applied contextual sequential pattern extraction techniques to epidemiological and meteorological data to identify the most significant climatic factors for dengue fever, and we investigated the relevance of the extracted patterns for the early warning of dengue outbreaks in French Guiana. The maximum temperature, minimum relative humidity, global brilliance, and cumulative rainfall were identified as determinants of dengue outbreaks, and the precise intervals of their values and variations were quantified according to the epidemiologic context. The strongest significant correlations were observed between dengue incidence and meteorological drivers after a 4-6-week lag. We demonstrated the use of contextual sequential patterns to better understand the determinants of the spatiotemporal spread of dengue fever in French Guiana. Future work should integrate additional variables and explore the notion of neighborhood for extracting sequential patterns. Dengue fever remains a major public health issue in French Guiana. The development of new methods to identify such specific characteristics becomes crucial in order to better understand and control spatiotemporal transmission. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  14. A Survey of Insecticide Resistance in Aedes albopictus (Diptera: Culicidae) During a 2014 Dengue Fever Outbreak in Guangzhou, China.

    Science.gov (United States)

    Yiguan, Wang; Xin, Liu; Chengling, Li; Su, Tianyun; Jianchao, Jin; Yuhong, Guo; Dongsheng, Ren; Zhicong, Yang; Qiyong, Liu; Fengxia, Meng

    2016-12-23

    A dengue fever outbreak in Guangzhou, Guangdong Province, China, in 2014 resulted in ∼37,000 cases and five deaths. Insecticides were sprayed to control the vector of this outbreak, Aedes albopictus (Skuse), a species of mosquito. Aedes albopictus specimens collected from Huadu District (HD), Huangpu District (HP), Luogang District (LG), and Nansha District (NS) in Guangzhou were evaluated using WHO-recommended bioassays for both larvae and adult mosquitoes to determine population resistance to deltamethrin, beta-cypermethrin, cypermethrin, permethrin, dichlorvos, temephos, propoxur, and DDT. Compared with a susceptible laboratory strain of Ae. albopictus (S-lab), all populations showed decreased sensitivities to the eight insecticides, with resistance ratios (RRs) ranging from 2.2 to 275. The RRs were 6.8-275 for pyrethroids, 2.2-4.4 for organophosphates, 5.7-9.0 for carbamates, and 5.3-94.3 for organochlorines. For adult mosquitoes, all populations were sensitive to dichlorvos with 100% mortalities. Mosquitoes from HP, LG, and NS were also sensitive to propoxur. But for other tested insecticides, different degrees of resistance (mortality rate ranging from 11.7% to 94.7%) were observed. Among the four field populations, the resistance levels are presented as follows in descending order: HP > HD > NS > LG. The levels among insecticides classes were pyrethroids > organochlorines > carbamates > organophosphates.

  15. A Study of Clinical Spectrum of Dengue Fever in A Tertiary Care Centre.

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    Dr. Gargi Pathak

    2016-12-01

    Full Text Available Introduction: Dengue 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 from paediatric department of civil hospital Ahmedabad. This study was designed to document the presenting features, laboratory results and outcome of dengue infection in children. Methodology: A prospective study was carried from October 2014-october 2015 and total of 126 patients were studied from age group between 1 month to 12 years. A detailed history, careful clinical examination and laboratory investigations were done in all the patients. Results and Conclusions: We documented Leucopenia as an early marker than thrombocytopenia and were seen in more numbers (47% in our study which was not found in the previous studies. Most common symptom was fever with body ache (73%. Majority of patients had platelet count between 50000-1 lakh. 55% had tested positive for dengue IgM and 44.4% had tested positive for dengue NS1. Wide variety of complications like hepatitis (20.6%, myocarditis (14.2%, dengue shock (11.1%, encephalitis (4.7%, Dengue haemorrhagic fever (4.7%, ARDS (2.3% were seen, which might indicate a change in serotype and epidemiology of the Dengue. Interestingly Bradycardia was seen in increased frequency subsequent to myocarditis with simultaneously raised CPK-MB levels. There were increased cases of coinfections like malaria, enteric, hepatitis, UTI, not seen previously .Out of 126 patients 6 patients expired.

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

    Science.gov (United States)

    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.

  17. Vascular Leakage in Dengue Hemorrhagic Fever Is Associated with Dengue Infected Monocytes, Monocyte Activation/Exhaustion, and Cytokines Production

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    Sirichan Chunhakan

    2015-01-01

    Full Text Available The vascular leakage was shown by the increment of hematocrit (Hct, dengue viral infected monocyte, monocyte status, and cytokines production in patients infected with dengue virus. Dengue viral antigens were demonstrated in monocytes (CD14+ from peripheral blood mononuclear cells. The increased levels of Hct, interleukin- (IL- 10, and tumor necrosis factor-alpha (TNF-α were detected in dengue fever (DF, dengue hemorrhagic fever (DHF and dengue shock syndrome (DSS patients as compared with other febrile illnesses (OFIs. The highest levels of Hct and IL-10 were detected in DSS patients as compared with other groups (P<0.05 especially on one day before and after defervescence. The unstimulated and lipopolysaccharide- (LPS- stimulated monocytes from DSS patients showed the significantly decreased of intracellular IL-1β and TNF-α. In addition, the lowest level of mean fluorescence intensity (MFI of CD11b expression on monocytes surface in DSS patients was also demonstrated. Furthermore, the negative correlations between IL-10 levels and intracellular IL-1β and MFI of CD11b expression in unstimulated and LPS-stimulated monocytes were also detected. Nevertheless, not only were the relationships between the prominent IL-10 and the suppression of intracellular monocyte secretion, namely, IL-1β, TNF-α, demonstrated but also the effect of vascular leakage was observed.

  18. Identification of factors for physicians to facilitate early differential diagnosis of scrub typhus, murine typhus, and Q fever from dengue fever in Taiwan.

    Science.gov (United States)

    Chang, Ko; Lee, Nan-Yao; Ko, Wen-Chien; Tsai, Jih-Jin; Lin, Wei-Ru; Chen, Tun-Chieh; Lu, Po-Liang; Chen, Yen-Hsu

    2017-02-01

    Dengue fever, rickettsial diseases, and Q fever are acute febrile illnesses with similar manifestations in tropical areas. Early differential diagnosis of scrub typhus, murine typhus, and Q fever from dengue fever may be made by understanding the distinguishing clinical characteristics and the significance of demographic and weather factors. We conducted a retrospective study to identify clinical, demographic, and meteorological characteristics of 454 dengue fever, 178 scrub typhus, 143 Q fever, and 81 murine typhus cases in three Taiwan hospitals. Case numbers of murine typhus and Q fever correlated significantly with temperature and rainfall; the scrub typhus case number was only significantly related with temperature. Neither temperature nor rainfall correlated with the case number of dengue fever. The rarity of dengue fever cases from January to June in Taiwan may be a helpful clue for diagnosis in the area. A male predominance was observed, as the male-to-female rate was 2.1 for murine typhus and 7.4 for Q fever. Multivariate analysis revealed the following six important factors for differentiating the rickettsial diseases and Q fever group from the dengue fever group: fever ≥8 days, alanine aminotransferase > aspartate aminotransferase, platelets >63,000/mL, C-reactive protein >31.9 mg/L, absence of bone pain, and absence of a bleeding syndrome. Understanding the rarity of dengue in the first half of a year in Taiwan and the six differentiating factors may help facilitate the early differential diagnosis of rickettsial diseases and Q fever from dengue fever, permitting early antibiotic treatment. Copyright © 2015. Published by Elsevier B.V.

  19. Potential Analysis of Promoting the Dengue Hemorrhagic Fever Prevention Through Youtube

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    Mara Ipa

    2014-11-01

    Full Text Available Background: Deal with health promotion efforts in terms of disease control using media or social networking is an innovative breakthrough in a region having a broad range of territory, such as Indonesia and others countries alike. The use of social media /video platforms such as youtube, vimeo, veoh in health promotion has been significantly increased. This study aims to determine the potential availability of information about dengue hemorrhagic fever (DHF on YouTube social media and social media potential of as a medium for dissemination of knowledge of health promotion. Methods: This study used a social media site or website which is the most popular video hosting sites in the world, ‘YouTube’, with the keyword of ‘dengue hemorrhagic fever’. The selected video directly associated with DHF, videos in English that were included in this study using Latin letters in the description of the video; with duration less than or equal to 5 minutes. 76 videos analyzed with content analysis methods. Results:Showed that 76 videos divided into categories of prevention, control, transmission, treatment, dengue fever treatment, and other categories. Other information classification categories explain the severity of dengue virus infection, dengue vector (morphology, bionomics, intrinsic phase dengue virus and some research conducted as dengue vaccine discovery efforts. Conclusion: The availability of information about dengue on YouTube social media is still very deficient. Recommendation: YouTube has the potential of social media as a medium for disseminating health promotion information about dengue.

  20. A epidemia de dengue/dengue hemorrágico no município do Rio de Janeiro, 2001/2002 The epidemic of dengue and hemorrhagic dengue fever in the city of Rio de Janeiro, 2001/2002

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    Clarisse Guimarães Casali

    2004-08-01

    Full Text Available O objetivo deste estudo foi avaliar a ocorrência dos principais sinais e sintomas dos casos de dengue clássico e dengue hemorrágico na epidemia de 2001-2002 do município do Rio de Janeiro. Foram analisados os 155.242 casos notificados ao Sistema de Informações de Agravos de Notificação, desde janeiro/2001, até junho/2002; deste total, excluindo-se os ignorados, 81.327 casos foram classificados como dengue clássico e 958 como dengue hemorrágico, com um total de 54 óbitos. Avaliaram-se as variáveis referentes à sintomatologia da doença. Manifestações gerais como febre, cefaléia, prostração, mialgia, náuseas e dor retro-orbitária tiveram alta incidência tanto no dengue clássico como no dengue hemorrágico. Por outro lado, manifestações hemorrágicas e algumas de maior gravidade como choque, hemorragia digestiva, petéquias, epistaxe, dor abdominal e derrame pleural, estiveram significativamente associadas ao dengue hemorrágico. Além disso, a evolução do quadro clínico para o óbito foi 34,8 vezes maior no dengue hemorrágico que no dengue clássico (OR=34,8; IC 19,7-61,3.The following study was intended to evaluate the occurrence of typical signs and symptoms in the cases of classic dengue and hemorrhagic dengue fever, during the 2001-2002 epidemic in the city of Rio de Janeiro. The authors reviewed 155,242 cases notified to the Information System of Notification Diseases, from January/2001 to June/2002: 81,327 cases were classified as classic dengue and 958 as hemorrhagic dengue fever, with a total of 60 deaths. Common symptoms, such as fever, headache, prostration, myalgia, nausea and retro-orbital pain, had a high incidence in both classic and hemorrhagic dengue fever. On the other hand, hemorrhagic signs and other signs of severe disease, such as shock, gastrointestinal bleeding, petechiae, epistaxis, abdominal pain and pleural effusion, were strongly associated to hemorrhagic dengue fever. Besides, the occurrence

  1. Bilateral eyelid ecchymosis and subconjunctival haemorrhage manifesting as presenting feature in a case of dengue haemorrhagic fever.

    Science.gov (United States)

    Jain, Sparshi; Goswami, Anup; Singh, Nidhi; Kaur, Savleen

    2015-10-01

    We report a case of bilateral eyelid ecchymosis and subconjunctival haemorrhage, a rare presenting feature of dengue haemorrhagic fever. A 17-year-old boy presented to the emergency department with complaints of redness in both eyes and vomiting. He had bilateral eyelid ecchymosis with subconjunctival haemorrhage. Complete blood count revealed a significantly reduced platelet count of 11000/µL suggestive of dengue haemorrhagic fever (DHF). Ocular manifestations were followed by other systemic haemorrhagic manifestations of dengue later on which violates the usual sequence of events of dengue fever. Bilateral eyelid ecchymosis is a rare clinical manifestation and a rare presenting feature of dengue fever and one has to keep high index of suspicion for presence of dengue whenever a case of fever presents with lid ecchymosis/haemorrhage. © The Author(s) 2014.

  2. Dengue fever in Czech travellers: A 10-year retrospective study in a tertiary care centre.

    Science.gov (United States)

    Trojánek, Milan; Maixner, Jan; Sojková, Naděžda; Kynčl, Jan; Roháčová, Hana; Marešová, Vilma; Stejskal, František

    2016-01-01

    Dengue fever is a frequent cause of morbidity in travellers. The objective was to describe the epidemiological and clinical characteristics of dengue fever in Czech travellers. This descriptive study includes patients with acute dengue fever diagnosed at Hospital Na Bulovce during 2004-2013. Data were collected and analysed retrospectively. A total of 132 patients (83 males and 49 females) of median age 33 years (IQR 29-40) were included. Diagnosis was established by NS1 antigen detection in 87/107 cases (81.3%) and/or RT-PCR in 50/72 (69.4%) and by serology in 25 cases (18.9%). Dengue was acquired in South-East Asia in 69 cases (52.3%), followed by South Asia (48 cases; 36.3%), Latin America (14; 10.6%) and Sub-Saharan Africa (1; 0.8%). The most frequent symptoms included fever, rash and headache. Initial leukocyte and lymphocyte counts were lower in patients who presented in the early phase (0-4 days), however, platelet count was lower and AST, ALT and LDH activity higher in patients with a longer symptoms duration (≥5 days). The clinical course was mostly uncomplicated. Dengue fever is becoming a frequent cause of fever in Czech travellers. Clinicians should be familiar with the typical clinical findings and novel diagnostic methods. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Intriguing olfactory proteins from the yellow fever mosquito, Aedes aegypti

    Science.gov (United States)

    Ishida, Yuko; Chen, Angela M.; Tsuruda, Jennifer M.; Cornel, Anthon J.; Debboun, Mustapha; Leal, Walter S.

    2004-09-01

    Four antennae-specific proteins (AaegOBP1, AaegOBP2, AaegOBP3, and AaegASP1) were isolated from the yellow fever mosquito, Aedes aegypti and their full-length cDNAs were cloned. RT-PCR indicated that they are expressed in female and, to a lesser extent, in male antennae, but not in control tissues (legs). AaegOBP1 and AaegOBP3 showed significant similarity to previously identified mosquito odorant-binding proteins (OBPs) in cysteine spacing pattern and sequence. Two of the isolated proteins have a total of eight cysteine residues. The similarity of the spacing pattern of the cysteine residues and amino acid sequence to those of previously identified olfactory proteins suggests that one of the cysteine-rich proteins (AaegOBP2) is an OBP. The other (AaegASP1) did not belong to any group of known OBPs. Structural analyses indicate that six of the cysteine residues in AaegOBP2 are linked in a similar pattern to the previously known cysteine pairing in OBPs, i.e., Cys-24 Cys-55, Cys-51 Cys-104, Cys-95 Cys-113. The additional disulfide bridge, Cys-38 Cys-125, knits the extended C-terminal segment of the protein to a predicted α2-helix. As indicated by circular dichroism (CD) spectra, the extra rigidity seems to prevent the predicted formation of a C-terminal α-helix at low pH.

  4. Role of platelet transfusion in children with bleeding in dengue fever.

    Science.gov (United States)

    Pothapregada, Sriram; Kamalakannan, Banupriya; Thulasingam, Mahalakshmy

    2015-12-01

    The indications for platelet transfusion in dengue fever are clearly defined in World Health Organization (WHO) guidelines (2011) for dengue fever, but physicians face practical difficulty in its implementation in an epidemic setting. On one hand there is an intense social pressure created by the panic-struck parents to transfuse platelets in presence of bleeding and on the other hand there is a need for its judicious use as the requirement is more than its availability. The study was aimed to assess the clinico-hematological parameters, and the requirement and need for platelet transfusion in children with dengue fever. All children (0-12 yr of age) diagnosed and confirmed with dengue fever at a tertiary care hospital in Puducherry between 1 August 2012 and 31 January 2015 were reviewed retrospectively from hospital case records as per the revised WHO guidelines for dengue fever. The diagnosis was confirmed by NS1 antigen- based ELISA test or dengue serology for IgM and IgG antibodies and the data were analyzed using SPSS 16.0 statistical software. Out of 261 cases of dengue fever, hemorrhagic manifestations were observed in 52 children (19.9%), which mainly included petechiae (38.5%), gum bleeding (34.6%) and melena (26.9%). Thrombocytopenia was seen in 211 (80.8%) cases. Bleeding manifestations were present in 20(39.2%), 8(15.7%), 13(25.5%) and 11(21.6%) cases with platelet count 1.50,000/mm3 respectively. Bleeding manifestations did not always correlate with platelet count in non-severe dengue infection in comparison to severe dengue infection. The most common mode of presentation of severe dengue infection was shock with 102(39.1%) cases and among them only 22 children (21.6%) had bleeding. About 17 children (6.5%) with severe dengue infection required platelet transfusion and out of them, 12 children (70.6%) had a platelet count <20,000/ mm3 whereas five children (29.4%) had platelet count in the range of 20,000-50,000/mm3. Platelet transfusion was required

  5. Impact of Wolbachia on infection with chikungunya and yellow fever viruses in the mosquito vector Aedes aegypti.

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    Andrew F van den Hurk

    Full Text Available Incidence of disease due to dengue (DENV, chikungunya (CHIKV and yellow fever (YFV viruses is increasing in many parts of the world. The viruses are primarily transmitted by Aedes aegypti, a highly domesticated mosquito species that is notoriously difficult to control. When transinfected into Ae. aegypti, the intracellular bacterium Wolbachia has recently been shown to inhibit replication of DENVs, CHIKV, malaria parasites and filarial nematodes, providing a potentially powerful biocontrol strategy for human pathogens. Because the extent of pathogen reduction can be influenced by the strain of bacterium, we examined whether the wMel strain of Wolbachia influenced CHIKV and YFV infection in Ae. aegypti. Following exposure to viremic blood meals, CHIKV infection and dissemination rates were significantly reduced in mosquitoes with the wMel strain of Wolbachia compared to Wolbachia-uninfected controls. However, similar rates of infection and dissemination were observed in wMel infected and non-infected Ae. aegypti when intrathoracic inoculation was used to deliver virus. YFV infection, dissemination and replication were similar in wMel-infected and control mosquitoes following intrathoracic inoculations. In contrast, mosquitoes with the wMelPop strain of Wolbachia showed at least a 10(4 times reduction in YFV RNA copies compared to controls. The extent of reduction in virus infection depended on Wolbachia strain, titer and strain of the virus, and mode of exposure. Although originally proposed for dengue biocontrol, our results indicate a Wolbachia-based strategy also holds considerable promise for YFV and CHIKV suppression.

  6. Review of Dengue Hemorrhagic Fever Fatal Cases Seen Among Adults: A Retrospective Study

    OpenAIRE

    Sing-Sin Sam; Sharifah Faridah Syed Omar; Boon-Teong Teoh; Juraina Abd-Jamil; Sazaly AbuBakar

    2013-01-01

    BACKGROUND: Dengue is a mosquito-borne viral disease endemic in many countries in the tropics and sub-tropics. The disease affects mainly children, but in recent years it is becoming more of an adult disease. Malaysia experienced a large dengue outbreak in 2006 to 2007, involving mostly adults, with a high number of deaths. METHODOLOGY/PRINCIPAL FINDINGS: We undertook a retrospective study to examine dengue death cases in our hospital from June 2006 to October 2007 with a view to determine if...

  7. A social-ecological analysis of community perceptions of dengue fever and Aedes aegypti in Machala, Ecuador.

    Science.gov (United States)

    Stewart Ibarra, Anna M; Luzadis, Valerie A; Borbor Cordova, Mercy J; Silva, Mercy; Ordoñez, Tania; Beltrán Ayala, Efraín; Ryan, Sadie J

    2014-11-04

    The growing burden of dengue fever and the lack of a vaccine or specific medical treatment have increased the urgency of the public health sector to identify alternative management strategies. A prevailing trend in Latin America has been a shift towards decentralized vector control programs with integrated management strategies, requiring significant intersectoral coordination, community engagement, and knowledge of the local social-ecological system (SES). Community perceptions and responses are a critical component of this system, since perceptions shape actions, and thus govern behavioral responses and acceptance of shifts in policy and management. We investigated perceptions, misconceptions, and local SES risk factors for dengue in high risk communities located at the urban periphery and center in Machala, Ecuador. We facilitated twelve focus group discussions with community members using semi-structured question guides and causal diagrams. Focus groups were recorded, transcribed, and coded to identify emergent themes using qualitative methods for theme analysis. To estimate the relative importance of the themes in each study area, we tabulated the number of focus groups in which each theme was present. Household surveys (n = 79) were conducted to further explore these themes, and we compared survey responses from the two areas using descriptive statistics. We identified thirty biophysical, political-institutional, and community-household risk factors for dengue. People at the periphery identified a greater number of risk factors. Dengue control required considerable investment of time and resources, which presented a greater challenge for women and people at the periphery. Common misperceptions included confusion with other febrile diseases, lack of knowledge of transmission mechanisms, and misconceptions about mosquito behavior. People perceived that dengue control programs had been limited by the lack of inter-institutional coordination and lack of social

  8. Computational Intelligence Method for Early Diagnosis Dengue Haemorrhagic Fever Using Fuzzy on Mobile Device

    Science.gov (United States)

    Salman, Afan; Lina, Yen; Simon, Christian

    2014-03-01

    Mortality from Dengue Haemorrhagic Fever (DHF) is still increasing in Indonesia particularly in Jakarta. Diagnosis of the dengue shall be made as early as possible so that first aid can be given in expectation of decreasing death risk. The Study will be conducted by developing expert system based on Computational Intelligence Method. On the first year, study will use the Fuzzy Inference System (FIS) Method to diagnose Dengue Haemorrhagic Fever particularly in Mobile Device consist of smart phone. Expert system application which particularly using fuzzy system can be applied in mobile device and it is useful to make early diagnosis of Dengue Haemorrhagic Fever that produce outcome faster than laboratory test. The evaluation of this application is conducted by performing accuracy test before and after validation using data of patient who has the Dengue Haemorrhagic Fever. This expert system application is easy, convenient, and practical to use, also capable of making the early diagnosis of Dengue Haemorraghic to avoid mortality in the first stage.

  9. Epidemiological trends and the effect of airport fever screening on prevention of domestic dengue fever outbreaks in Taiwan, 1998-2007.

    Science.gov (United States)

    Kuan, Mei-Mei; Lin, Ting; Chuang, Jen-Hsiang; Wu, Ho-Sheng

    2010-08-01

    This study aimed to examine the epidemiological trends in dengue infection and the impact of imported cases and airport fever screening on community transmission in Taiwan, a dengue non-endemic island. All of the dengue case data were obtained from the surveillance system of the Taiwan Center for Disease Control and were analyzed by Pearson correlations, linear regression, and geographical information system (GIS)-based mapping. The impact of implementing airport fever screening was evaluated using the Student's t-test and two-way analysis of variance. A total of 10 351 dengue cases, including 7.1% of imported cases were investigated between 1998 and 2007. The majority of indigenous dengue cases (98.5%) were significantly clustered in southern Taiwan; 62.9% occurred in the metropolitan areas. The seasonality of dengue cases showed a peak from September to November. Airport fever screening was successful in identifying 45% (244/542 ; 95% confidence interval 33.1-57.8%) of imported dengue cases with fever. However, no statistical difference was found regarding the impact on community transmission when comparing the presence and absence of airport fever screening. Our results show that airport fever screening had a positive effect on partially blocking the local transmission of imported dengue cases, while those undetected cases due to latent or asymptomatic infection would be the source of new dengue outbreaks each year. Copyright © 2010 International Society for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

  10. Insect Repellents: Modulators of mosquito odorant receptor activity

    Science.gov (United States)

    Mosquitoes vector numerous pathogens that cause diseases including malaria, yellow fever, dengue fever and chikungunya. DEET, IR3535, Picaridin and 2-undecanone are insect repellents that are used to prevent interactions between humans and a broad array of disease vectors including mosquitoes. While...

  11. Dengue: a global threat.

    Science.gov (United States)

    Thisyakorn, Usa; Thisyakorn, Chule

    2015-01-01

    Dengue, a mosquito-borne viral disease, is currently an expanding global problem. The disease is caused by four closely related dengue serotypes; it ranges from asymptomatic infection to undifferentiated fever, dengue fever (DF) and dengue hemorrhagic fever (DHF). DHF is characterized by fever, bleeding diathesis and a tendency to develop apotentially fatal shock syndrome. Dengue infection with organ impairment mainly involves the central nervous system and liver. Consistent hematological findings include vasculopathy, coagulopathy and thrombocytopenia. Laboratory diagnoses include virus isolation, serology, and detection ofdengue ribonucleic acid. Successful treatment, which is mainly supportive, depends on early recognition of the disease and careful monitoring for shock. A severity-based revised dengue classification for medical interventions has been developed and validated in many countries. So far however, there has not been any specific dengue treatment; prevention is currently limited to vector control measures. The world's first, large-scale dengue vaccine, efficacy study demonstrated its efficacy and a reduction of dengue's severity in a study of more than 10,000 volunteers in Asia. Initial safety data are consistent with a good safety profile.

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

    Science.gov (United States)

    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

  13. The combined action of phytolarvicides for the control of dengue fever vector, Aedes aegypti

    Directory of Open Access Journals (Sweden)

    Adelia Grzybowski

    2012-06-01

    Full Text Available Amongst other botanical sources, Annona muricata L., Annonaceae, seeds and Piper nigrum L., Piperaceae, fruits are particularly enriched with acetogenins and piperine-related amides, respectively. These crude ethanolic extracts are potent Aedes aegypti bioactives that can kill Aedes aegypti larvae (dengue fever mosquito. A. muricata displayed a 93.48 µg/mL LC50 and P. nigrum an 1.84 µg/mL LC50. An uncommon pharmacognostical/toxicological approach was used, namely different combinations of both extracts to achieve an improved lethal effect on the larvae. The independence test (χ² was utilized to evaluate the combination of the two crude extracts. All of the tested combinations behaved synergistically and these novel results were attributed to the completely different biochemical mechanisms of the differentiated chemical substances that were present in the two botanical sources. Besides the two above selected plants, Melia azedarach L., Meliaceae, Origanum vulgare L., Lamiaceae, and Ilex paraguariensis A. St.-Hil., Aquifoliaceae, in order of decreasing toxicity, may also be sought as potential extracts for the sake of synergic combinations.

  14. Modeling and projection of dengue fever cases in Guangzhou based on variation of weather factors.

    Science.gov (United States)

    Li, Chenlu; Wang, Xiaofeng; Wu, Xiaoxu; Liu, Jianing; Ji, Duoying; Du, Juan

    2017-12-15

    Dengue fever is one of the most serious vector-borne infectious diseases, especially in Guangzhou, China. Dengue viruses and their vectors Aedes albopictus are sensitive to climate change primarily in relation to weather factors. Previous research has mainly focused on identifying the relationship between climate factors and dengue cases, or developing dengue case models with some non-climate factors. However, there has been little research addressing the modeling and projection of dengue cases only from the perspective of climate change. This study considered this topic using long time series data (1998-2014). First, sensitive weather factors were identified through meta-analysis that included literature review screening, lagged analysis, and collinear analysis. Then, key factors that included monthly average temperature at a lag of two months, and monthly average relative humidity and monthly average precipitation at lags of three months were determined. Second, time series Poisson analysis was used with the generalized additive model approach to develop a dengue model based on key weather factors for January 1998 to December 2012. Data from January 2013 to July 2014 were used to validate that the model was reliable and reasonable. Finally, future weather data (January 2020 to December 2070) were input into the model to project the occurrence of dengue cases under different climate scenarios (RCP 2.6 and RCP 8.5). Longer time series analysis and scientifically selected weather variables were used to develop a dengue model to ensure reliability. The projections suggested that seasonal disease control (especially in summer and fall) and mitigation of greenhouse gas emissions could help reduce the incidence of dengue fever. The results of this study hope to provide a scientifically theoretical basis for the prevention and control of dengue fever in Guangzhou. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Clinical features and dynamic ordinary laboratory tests differentiating dengue fever from other febrile illnesses in children.

    Science.gov (United States)

    Chen, Chih-Ho; Huang, Yi-Chuan; Kuo, Kuang-Che; Li, Chung-Chen

    2017-06-30

    Dengue fever is not easily to be diagnosed before presentation of the classic symptoms. The study aimed to investigate the clinical features and dynamic laboratory tests in pediatric patients to facilitate dengue diagnosis. This retrospective study examined the medical records of all pediatric patients who were clinically suspected to have dengue from June to December 2014. Laboratory-positive dengue cases were confirmed by detecting non-structural protein NS1, reverse transcription-polymerase chain reaction of dengue virus, and dengue-specific IgM seroconversion. Of the 317 pediatric cases clinically suspected of dengue, 205 were laboratory-positive and 112 were laboratory-negative. In laboratory-positive cases, the most common clinical manifestation was skin rash in 156 (76.1%). Leukopenia occurred on days 1-5; thrombocytopenia, on days 2-7; prolonged activated partial thromboplastin time (aPTT), on days 1-4; and elevated transaminase levels, on days 3-11; and low CRP, on days 0-14. The specificity and positive predictive value (PPV) of combining of rash, itching and petechiae increased up to 100%. The PPV of combining of leukopenia, thrombocytopenia, and elevated transaminase levels reached 100% on day 2 as well as days 6-8. Leukopenia, thrombocytopenia, elevated aPTT, elevated transaminase levels, and low CRP could be used to differentiate dengue fever from other febrile illnesses. During dengue epidemics, combinations of the symptoms and laboratory findings are helpful to physicians for accurate diagnosis of dengue fever. Copyright © 2017. Published by Elsevier B.V.

  16. Using geographically weighted regression (GWR) to explore spatial varying relationships of immature mosquitoes and human densities with the incidence of dengue

    DEFF Research Database (Denmark)

    Lin, Chia-Hsien; Wen, Tzai-Hung

    2011-01-01

    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...

  17. Spatiotemporal analysis of indigenous and imported dengue fever cases in Guangdong province, China

    Directory of Open Access Journals (Sweden)

    Li Zhongjie

    2012-06-01

    Full Text Available Abstract Background Dengue fever has been a major public health concern in China since it re-emerged in Guangdong province in 1978. This study aimed to explore spatiotemporal characteristics of dengue fever cases for both indigenous and imported cases during recent years in Guangdong province, so as to identify high-risk areas of the province and thereby help plan resource allocation for dengue interventions. Methods Notifiable cases of dengue fever were collected from all 123 counties of Guangdong province from 2005 to 2010. Descriptive temporal and spatial analysis were conducted, including plotting of seasonal distribution of cases, and creating choropleth maps of cumulative incidence by county. The space-time scan statistic was used to determine space-time clusters of dengue fever cases at the county level, and a geographical information system was used to visualize the location of the clusters. Analysis were stratified by imported and indigenous origin. Results 1658 dengue fever cases were recorded in Guangdong province during the study period, including 94 imported cases and 1564 indigenous cases. Both imported and indigenous cases occurred more frequently in autumn. The areas affected by the indigenous and imported cases presented a geographically expanding trend over the study period. The results showed that the most likely cluster of imported cases (relative risk = 7.52, p  Conclusions This study demonstrated that the geographic range of imported and indigenous dengue fever cases has expanded over recent years, and cases were significantly clustered in two heavily urbanised areas of Guangdong province. This provides the foundation for further investigation of risk factors and interventions in these high-risk areas.

  18. Spatiotemporal analysis of indigenous and imported dengue fever cases in Guangdong province, China.

    Science.gov (United States)

    Li, Zhongjie; Yin, Wenwu; Clements, Archie; Williams, Gail; Lai, Shengjie; Zhou, Hang; Zhao, Dan; Guo, Yansha; Zhang, Yonghui; Wang, Jinfeng; Hu, Wenbiao; Yang, Weizhong

    2012-06-12

    Dengue fever has been a major public health concern in China since it re-emerged in Guangdong province in 1978. This study aimed to explore spatiotemporal characteristics of dengue fever cases for both indigenous and imported cases during recent years in Guangdong province, so as to identify high-risk areas of the province and thereby help plan resource allocation for dengue interventions. Notifiable cases of dengue fever were collected from all 123 counties of Guangdong province from 2005 to 2010. Descriptive temporal and spatial analysis were conducted, including plotting of seasonal distribution of cases, and creating choropleth maps of cumulative incidence by county. The space-time scan statistic was used to determine space-time clusters of dengue fever cases at the county level, and a geographical information system was used to visualize the location of the clusters. Analysis were stratified by imported and indigenous origin. 1658 dengue fever cases were recorded in Guangdong province during the study period, including 94 imported cases and 1564 indigenous cases. Both imported and indigenous cases occurred more frequently in autumn. The areas affected by the indigenous and imported cases presented a geographically expanding trend over the study period. The results showed that the most likely cluster of imported cases (relative risk = 7.52, p dengue fever cases has expanded over recent years, and cases were significantly clustered in two heavily urbanised areas of Guangdong province. This provides the foundation for further investigation of risk factors and interventions in these high-risk areas.

  19. Survey of the first local dengue fever infection in Xishuangbanna Prefecture of Yunnan Province.%西双版纳首例本地感染登革热调查处理

    Institute of Scientific and Technical Information of China (English)

    朱进; 李鸿斌; 申剑波; 车英

    2011-01-01

    Objective To trace the source of the fist local dengue fever infection in Xishuangbanna Preecture of Yunnan Province. Methods Epidemiological survey of the fist case of dengue fever in the local residents was made and the focus of infection was properly managed and treated. Results There was one local infected dengue fever cases in Xishuangbanna Prefecture and 12 latent infections. Conclusion The local conditions suitable for transmission of dengue fever,thus the measures of control mosquito vectors and health education be carried out to reduce the possibility of occurrence of dengue fever infection.%目的 调查了解此次本地感染登革热病例发生原因.方法 首例本地感染登革热流行病学调查并对疫点采取处置措施.结果 本地感染登革热病例l例,登革热本地隐性感染者12例.结论 勐海县纳京村委会纳京九组有再次发生登革热疫情的可能性,需注重做好登革热防控工作及知识普及.

  20. Pharmacological validation of an inward-rectifier potassium (Kir channel as an insecticide target in the yellow fever mosquito Aedes aegypti.

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    Matthew F Rouhier

    Full Text Available Mosquitoes are important disease vectors that transmit a wide variety of pathogens to humans, including those that cause malaria and dengue fever. Insecticides have traditionally been deployed to control populations of disease-causing mosquitoes, but the emergence of insecticide resistance has severely limited the number of active compounds that are used against mosquitoes. Thus, to improve the control of resistant mosquitoes there is a need to identify new insecticide targets and active compounds for insecticide development. Recently we demonstrated that inward rectifier potassium (Kir channels and small molecule inhibitors of Kir channels offer promising new molecular targets and active compounds, respectively, for insecticide development. Here we provide pharmacological validation of a specific mosquito Kir channel (AeKir1 in the yellow fever mosquito Aedes aegypti. We show that VU590, a small-molecule inhibitor of mammalian Kir1.1 and Kir7.1 channels, potently inhibits AeKir1 but not another mosquito Kir channel (AeKir2B in vitro. Moreover, we show that a previously identified inhibitor of AeKir1 (VU573 elicits an unexpected agonistic effect on AeKir2B in vitro. Injection of VU590 into the hemolymph of adult female mosquitoes significantly inhibits their capacity to excrete urine and kills them within 24 h, suggesting a mechanism of action on the excretory system. Importantly, a structurally-related VU590 analog (VU608, which weakly blocks AeKir1 in vitro, has no significant effects on their excretory capacity and does not kill mosquitoes. These observations suggest that the toxic effects of VU590 are associated with its inhibition of AeKir1.

  1. Complementary alternative medicine use among patients with dengue fever in the hospital setting: a cross-sectional study in Malaysia.

    Science.gov (United States)

    Ching, SiewMooi; Ramachandran, Vasudevan; Gew, Lai Teck; Lim, Sazlyna Mohd Sazlly; Sulaiman, Wan Aliaa Wan; Foo, Yoke Loong; Zakaria, Zainul Amiruddin; Samsudin, Nurul Huda; Lau, Paul Chih Ming Chih; Veettil, Sajesh K; Hoo, Fankee

    2016-01-29

    In Malaysia, the number of reported cases of dengue fever demonstrates an increasing trend. Since dengue fever has no vaccine or antiviral treatment available, it has become a burden. Complementary and alternative medicine (CAM) has become one of the good alternatives to treat the patients with dengue fever. There is limited study on the use of CAM among patients with dengue fever, particularly in hospital settings. This study aims to determine the prevalence, types, reasons, expenditure, and resource of information on CAM use among patients with dengue fever. This is a descriptive, cross-sectional study of 306 patients with dengue fever, which was carried out at the dengue clinic of three hospitals. Data were analysed using IBM SPSS Statistics version 21.0 and logistic regression analysis was used to determine the factors associated with CAM use. The prevalence of CAM use was 85.3% among patients with dengue fever. The most popular CAMs were isotonic drinks (85.8%), crab soup (46.7%) and papaya leaf extract (22.2%). The most common reason for CAM use was a good impression of CAM from other CAM users (33.3%). The main resource of information on CAM use among patients with dengue fever was family (54.8%). In multiple logistic regression analysis, dengue fever patients with a tertiary level are more likely to use CAM 5.8 (95% confidence interval (CI 1.62-20.45) and 3.8 (95% CI 1.12-12.93) times than secondary level and primary and below respectively. CAM was commonly used by patients with dengue fever. The predictor of CAM use was a higher level of education.

  2. Susceptibility of Aedes flavopictus miyarai and Aedes galloisi mosquito species in Japan to dengue type 2 virus

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    Raweewan Srisawat

    2016-05-01

    Conclusions: Ae. albopictus is a well-known candidate for dengue transmission in Japan. However, our data suggest that Ae. f. miyarai from Ishigaki Island (near Okinawa Island and Ae. galloisi from Hokkaido (Northern Japan should also be regarded as potential vectors for dengue transmission in these regions. Further studies on these mosquitoes should be conducted.

  3. Review of Dengue hemorrhagic fever fatal cases seen among adults: a retrospective study.

    Science.gov (United States)

    Sam, Sing-Sin; Omar, Sharifah Faridah Syed; Teoh, Boon-Teong; Abd-Jamil, Juraina; AbuBakar, Sazaly

    2013-01-01

    Dengue is a mosquito-borne viral disease endemic in many countries in the tropics and sub-tropics. The disease affects mainly children, but in recent years it is becoming more of an adult disease. Malaysia experienced a large dengue outbreak in 2006 to 2007, involving mostly adults, with a high number of deaths. We undertook a retrospective study to examine dengue death cases in our hospital from June 2006 to October 2007 with a view to determine if there have been changes in the presentation of severe to fatal dengue. Nine of ten fatal cases involved adult females with a median age of 32 years. All had secondary dengue infection. The mean duration of illness prior to hospitalization was 4.7 days and deaths occurred at an average of 2.4 days post-admission. Gastrointestinal pain, vomiting, diarrhea, intravascular leakages and bleeding occurred in the majority of cases. DSS complicated with severe bleeding, multi-organ failure and coagulopathy were the primary causes of deaths. Seven patients presented with thrombocytopenia and hypoalbuminemia, five of which had hemoconcentration and increased ALT and AST indicative of liver damage. Co-morbidities particularly diabetes mellitus was common in our cohort. Prominent unusual presentations included acute renal failure, acute respiratory distress syndrome, myocarditis with pericarditis, and hemorrhages over the brain and heart. In our cohort, dengue fatalities are seen primarily in adult females with secondary dengue infection. The majority of the patients presented with common clinical and laboratory warning signs of severe dengue. Underlying co-morbidities may contribute to the rapid clinical deterioration in severe dengue. The uncommon presentations of dengue are likely a reflection of the changing demographics where adults are now more likely to contract dengue in dengue endemic regions.

  4. Review of Dengue hemorrhagic fever fatal cases seen among adults: a retrospective study.

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    Sing-Sin Sam

    Full Text Available BACKGROUND: Dengue is a mosquito-borne viral disease endemic in many countries in the tropics and sub-tropics. The disease affects mainly children, but in recent years it is becoming more of an adult disease. Malaysia experienced a large dengue outbreak in 2006 to 2007, involving mostly adults, with a high number of deaths. METHODOLOGY/PRINCIPAL FINDINGS: We undertook a retrospective study to examine dengue death cases in our hospital from June 2006 to October 2007 with a view to determine if there have been changes in the presentation of severe to fatal dengue. Nine of ten fatal cases involved adult females with a median age of 32 years. All had secondary dengue infection. The mean duration of illness prior to hospitalization was 4.7 days and deaths occurred at an average of 2.4 days post-admission. Gastrointestinal pain, vomiting, diarrhea, intravascular leakages and bleeding occurred in the majority of cases. DSS complicated with severe bleeding, multi-organ failure and coagulopathy were the primary causes of deaths. Seven patients presented with thrombocytopenia and hypoalbuminemia, five of which had hemoconcentration and increased ALT and AST indicative of liver damage. Co-morbidities particularly diabetes mellitus was common in our cohort. Prominent unusual presentations included acute renal failure, acute respiratory distress syndrome, myocarditis with pericarditis, and hemorrhages over the brain and heart. CONCLUSIONS: In our cohort, dengue fatalities are seen primarily in adult females with secondary dengue infection. The majority of the patients presented with common clinical and laboratory warning signs of severe dengue. Underlying co-morbidities may contribute to the rapid clinical deterioration in severe dengue. The uncommon presentations of dengue are likely a reflection of the changing demographics where adults are now more likely to contract dengue in dengue endemic regions.

  5. Review of Dengue Hemorrhagic Fever Fatal Cases Seen Among Adults: A Retrospective Study

    Science.gov (United States)

    Sam, Sing-Sin; Omar, Sharifah Faridah Syed; Teoh, Boon-Teong; Abd-Jamil, Juraina; AbuBakar, Sazaly

    2013-01-01

    Background Dengue is a mosquito-borne viral disease endemic in many countries in the tropics and sub-tropics. The disease affects mainly children, but in recent years it is becoming more of an adult disease. Malaysia experienced a large dengue outbreak in 2006 to 2007, involving mostly adults, with a high number of deaths. Methodology/Principal Findings We undertook a retrospective study to examine dengue death cases in our hospital from June 2006 to October 2007 with a view to determine if there have been changes in the presentation of severe to fatal dengue. Nine of ten fatal cases involved adult females with a median age of 32 years. All had secondary dengue infection. The mean duration of illness prior to hospitalization was 4.7 days and deaths occurred at an average of 2.4 days post-admission. Gastrointestinal pain, vomiting, diarrhea, intravascular leakages and bleeding occurred in the majority of cases. DSS complicated with severe bleeding, multi-organ failure and coagulopathy were the primary causes of deaths. Seven patients presented with thrombocytopenia and hypoalbuminemia, five of which had hemoconcentration and increased ALT and AST indicative of liver damage. Co-morbidities particularly diabetes mellitus was common in our cohort. Prominent unusual presentations included acute renal failure, acute respiratory distress syndrome, myocarditis with pericarditis, and hemorrhages over the brain and heart. Conclusions In our cohort, dengue fatalities are seen primarily in adult females with secondary dengue infection. The majority of the patients presented with common clinical and laboratory warning signs of severe dengue. Underlying co-morbidities may contribute to the rapid clinical deterioration in severe dengue. The uncommon presentations of dengue are likely a reflection of the changing demographics where adults are now more likely to contract dengue in dengue endemic regions. PMID:23658849

  6. Blood Meal Analysis of Mosquitoes Involved in a Rift Valley fever Outbreak

    Science.gov (United States)

    Background: Rift Valley fever (RVF) is a zoonosis of domestic ruminants in Africa. Bloodfed mosquitoes collected during the 2006-2007 RVF outbreak in Kenya were analyzed to determine the virus infection status and animal source of the bloodmeals. Bloodmeals from individual mosquito abdomens were sc...

  7. First report of sylvatic DENV-2-associated dengue hemorrhagic fever in West Africa.

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    Leticia Franco

    2011-08-01

    Full Text Available Dengue virus (DENV circulates in human and sylvatic cycles. Sylvatic strains are both ecologically and evolutionarily distinct from endemic viruses. Although sylvatic dengue cycles occur in West African countries and Malaysia, only a few cases of mild human disease caused by sylvatic strains and one single case of dengue hemorrhagic fever in Malaysia have been reported. Here we report a case of dengue hemorrhagic fever (DHF with thrombocytopenia (13000/µl, a raised hematocrit (32% above baseline and mucosal bleeding in a 27-year-old male returning to Spain in November 2009 after visiting his home country Guinea Bissau. Sylvatic DENV-2 West African lineage was isolated from blood and sera. This is the first case of DHF associated with sylvatic DENV-2 in Africa and the second case worldwide of DHF caused by a sylvatic strain.

  8. First report of sylvatic DENV-2-associated dengue hemorrhagic fever in West Africa.

    Science.gov (United States)

    Franco, Leticia; Palacios, Gustavo; Martinez, José Antonio; Vázquez, Ana; Savji, Nazir; De Ory, Fernando; Sanchez-Seco, María Paz; Martín, Dolores; Lipkin, W Ian; Tenorio, Antonio

    2011-08-01

    Dengue virus (DENV) circulates in human and sylvatic cycles. Sylvatic strains are both ecologically and evolutionarily distinct from endemic viruses. Although sylvatic dengue cycles occur in West African countries and Malaysia, only a few cases of mild human disease caused by sylvatic strains and one single case of dengue hemorrhagic fever in Malaysia have been reported. Here we report a case of dengue hemorrhagic fever (DHF) with thrombocytopenia (13000/µl), a raised hematocrit (32% above baseline) and mucosal bleeding in a 27-year-old male returning to Spain in November 2009 after visiting his home country Guinea Bissau. Sylvatic DENV-2 West African lineage was isolated from blood and sera. This is the first case of DHF associated with sylvatic DENV-2 in Africa and the second case worldwide of DHF caused by a sylvatic strain.

  9. Transcriptome Sequencing Analysis and Functional Identification of Sex Differentiation Genes from the Mosquito Parasitic Nematode, Romanomermis wuchangensis

    OpenAIRE

    Duan, Mingyue; Xiong, Jinfeng; Lu, Dandan; Wang, Guoxiu; Ai, Hui

    2016-01-01

    Mosquito-transmitted diseases like malaria and dengue fever are global problem and an estimated 50–100 million of dengue or dengue hemorrhagic fever cases are reported worldwide every year. The mermithid nematode Romanomermis wuchangensis has been successfully used as an ecosystem-friendly biocontrol agent for mosquito prevention in laboratory studies. However, this nematode can not undergo sex differentiation in vitro culture, which has seriously affected their application of biocontrol in t...

  10. Vector competence of Aedes albopictus from Houston, Texas, for dengue serotypes 1 to 4, yellow fever and Ross River viruses.

    Science.gov (United States)

    Mitchell, C J; Miller, B R; Gubler, D J

    1987-09-01

    A combination of virus infection and transmission experiments showed that a Houston, Texas strain of Aedes albopictus is a competent vector for dengue (DEN), yellow fever (YF) and Ross River (RR) viruses. However, at 14 days incubation, DEN virus infection rates in a Puerto Rican strain of Aedes aegypti were significantly higher for each of the four DEN serotypes, except DEN-1, than in Houston Ae. albopictus fed simultaneously on the same virus suspensions. The degree of correlation between disseminated DEN infection rates in Houston Ae. albopictus and transmission to an in vitro system ranged from 42 to 88% for the four DEN serotypes. No significant difference was noted in YF virus infection rates or transmission rates in the two mosquito species fed on the same virus suspensions and incubated for the same time period. Also, RR virus infection and transmission rates in Houston and Hawaiian strains of Ae. albopictus were generally comparable.

  11. Factors influencing the seasonal abundance of Aedes (Stegomyia) aegypti and the control strategy of dengue and dengue haemorrhagic fever in Thanlyin Township, Yangon City, Myanmar.

    Science.gov (United States)

    Oo, T T; Storch, V; Madon, M B; Becker, N

    2011-08-01

    From June 2006 to May 2007, mosquito surveys were conducted in Thanlyin Township, Yangon City, Myanmar, to determine factors influencing the abundance of Aedes aegypti (Stegomyia aegypti) during the rainy season. Both the biological and environmental factors were included in this study. Increase in the hatchability of egg, larval survival rate, the shortened larval life-span and increased pupation rates supplemented by rainfall (i.e. continuous flooding of the containers, stimulate the continuous hatching of eggs) were observed for correlation with the increase in population density of Ae. aegypti during the rainy season in the study area. Control strategy of Ae. aegypti to analyze the infestation in the community (study area) with larval Ae. aegypti, integrated management measures including health education, attitudes and practices regarding dengue and dengue haemorrhagic fever, transmission of the disease and possible preventive measures, reduction of breeding sites and testing the efficacy of Bacillus thuringiensis israelensis (B.t.i.) with respect to the reduction level of Ae. aegypti larvae in breeding sources, were taken into consideration.

  12. Container productivity, daily survival rates and dispersal of Aedes aegypti mosquitoes in a high income dengue epidemic neighbourhood of Rio de Janeiro: presumed influence of differential urban structure on mosquito biology

    National Research Council Canada - National Science Library

    David, Mariana Rocha; Lourenço-de-Oliveira, Ricardo; de Freitas, Rafael Maciel

    2009-01-01

    ... and, consequently, dengue transmission. Container productivity, probability of daily survival (PDS) and dispersal rates were estimated for mosquito populations in a high income neighbourhood of Rio de Janeiro...

  13. Clinical presentation and laboratory findings for the first autochthonous cases of dengue fever in Madeira island, Portugal, October 2012.

    Science.gov (United States)

    Alves, M J; Fernandes, P L; Amaro, F; Osório, H; Luz, T; Parreira, P; Andrade, G; Zé-Zé, L; Zeller, H

    2013-02-07

    An outbreak of dengue fever in Madeira island was reported in 2012. Clinical and laboratory findings of the first two laboratory-confirmed autochthonous cases are reported. Both cases had fever (≥38 °C) and petechial rash. Symptoms also included myalgia, asthenia, nausea, vomiting, anorexia, diffuse abdominal pain, and diarrhoea. The two cases were confirmed by serology and one tested positive for a dengue viral sequence. Dengue virus serotype DEN-1 was identified with probable Central or South American origin.

  14. Evaluation of the importance of fever with respect to dengue prognosis according to the 2009 WHO classification: a retrospective study

    OpenAIRE

    Tukasan, Caroline; Furlan, Nathália Barbosa; Estofolete, Cássia Fernanda; Nogueira,Maurício Lacerda; da Silva, Natal Santos

    2017-01-01

    Background The 2009 revised World Health Organization (WHO) guidelines for dengue describe fever as the core symptom. Accordingly, the diagnosis of non-febrile patients is complicated. The aim of this study was to evaluate the importance of fever in patients with dengue according to the 2009 revised WHO classification. Methods In this study, we assessed 30,670 dengue cases using enzyme-linked immunosorbent assay, detection of the non-structural protein 1, or polymerase chain reaction for diag...

  15. Paediatric Dengue Fever diagnosed through parents' epidemiologic report and preventive strategy during the acute phase of infection.

    Science.gov (United States)

    Poddighe, Dimitri; Bonomelli, Irene; Giardinetti, Silvia; Nedbal, Marco; Bruni, Paola

    2016-01-01

    In Europe, Dengue Fever is one of the most frequent imported diseases and also autochthonous cases occurred in areas where the insect vector is present. Here, we describe a child returning from Philippines and diagnosed with Dengue Fever, through the information provided by parents about an ongoing outbreak in their municipality. An appropriate clinical management in the hospital was established to monitor the occurrence of complications and to cancel the risk of dengue virus transmission in the acute phase of infection.

  16. Evaluation of the importance of fever with respect to dengue prognosis according to the 2009 WHO classification: a retrospective study

    OpenAIRE

    Tukasan, Caroline; Furlan, Nathália Barbosa; Estofolete, Cássia Fernanda; Nogueira, Maurício Lacerda; da Silva, Natal Santos

    2017-01-01

    Background The 2009 revised World Health Organization (WHO) guidelines for dengue describe fever as the core symptom. Accordingly, the diagnosis of non-febrile patients is complicated. The aim of this study was to evaluate the importance of fever in patients with dengue according to the 2009 revised WHO classification. Methods In this study, we assessed 30,670 dengue cases using enzyme-linked immunosorbent assay, detection of the non-structural protein 1, or polymerase chain reaction for diag...

  17. Cellulose-based diagnostic devices for diagnosing serotype-2 dengue fever in human serum.

    Science.gov (United States)

    Wang, Hsi-Kai; Tsai, Cheng-Han; Chen, Kuan-Hung; Tang, Chung-Tao; Leou, Jiun-Shyang; Li, Pi-Chun; Tang, Yin-Liang; Hsieh, Hsyue-Jen; Wu, Han-Chung; Cheng, Chao-Min

    2014-02-01

    Here, two types of cellulose-based in vitro diagnostic devices are demonstrated for the diagnosis of dengue virus infection in both buffer system and human serum: 1) paper-based ELISA for providing the semiquantitative information of the disease activity of serotype-2 dengue fever to healthcare persons (i.e., monitoring the disease activity with a specific serotype in single patients); 2) lateral flow immunoassays to screen for infection with serotype-2 dengue fever (i.e., rapid YES or NO diagnosis prepared for large populations, in terms of global public health). Paper-based ELISA (specific to serotype-2 dengue fever), which builds off of our previous studies and a revised previous ELISA procedure, owns multiple advantages: 1) high sensitivity (about 40 times higher than the current ELISA-based approaches, due to our therapeutic-based monoclonal antibody) and specificity (specific to dengue virus serotype-2 nonstructural protein-1 antigens); 2) tiny amount of sample and reagent used for single tests; 3) short operating duration (i.e., rapid diagnostic device); and, 4) inexpensiveness (appropriate for use in all developing and underdeveloped nations of the world). Due to the higher sensitivity and shorter operating duration of paper-based ELISA (compared with conventional ELISA, and lateral flow immunoassays also performed in this study), this study has not only been able to perform the diagnosis of dengue virus serotype-2 nonstructural protein-1 antigens in both buffer system and human serum but also to evaluate dengue virus serotype-2 envelope proteins in the buffer system, thus successfully achieving the first such use of these proteins as the target antigen for the development of diagnostic tools. These results provide a more comprehensive understanding for the genesis of dengue fever diagnostic tools (through antibody-antigen recognition).

  18. SECONDARY BACTERIAL INFECTION IN ADULT PATIENTS WITH PROLONGED AND SEVERE DENGUE FEVER

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    Anil Kumar

    2016-05-01

    Full Text Available INTRODUCTION Generally, in dengue shock syndrome antibiotics are not advised. But unrecognised bacterial infection is likely to contribute to morbidity and mortality, probably because of increased vascular permeability. OBJECTIVES To assess the incidence of secondary bacterial infection in adult patients with prolonged and severe dengue fever. METHODS A prospective study was conducted recruiting patients with confirmed acute dengue infection who had prolonged fever (>5 days. Prior to institution of antibiotic therapy, two sets of blood cultures were taken from patients. Demographic, clinical, haematological and biochemical parameters were recorded. Severity of fever & associated symptoms assessed. Ultrasonography done to find out development of ascites and pleural effusions. RESULTS Sixty patients (60.0% males with a mean age of 33.5 years (SD 12.1 were studied. The average duration of fever was 6.9 days (SD 1.6. Fifteen patients (25% had bacterial isolates in their blood cultures; Staphylococcus aureus (n=3, coliforms (n=7, pseudomonas (n=2 and 3 had mixed growths. The culture positive group had severe body aches and joints paint at admission and high grade fever, third space fluid accumulation and significant drop in platelets compared to culture-negative group. CONCLUSIONS A quarter of dengue patients with prolonged fever had a bacterial isolate. Culture-positive patients appeared more ill with body aches and had higher degrees of fever during the course of the illness. Increased vascular permeability may predispose to bacterial seepage into blood. Although white cell count is not helpful in detecting bacteraemia in dengue fever, low platelet count and severe symptoms at presentation may be helpful.

  19. Evaluation of Hydrologic and Meteorological Impacts on Dengue Fever Incidences in Southern Taiwan using Time- Frequency Method

    Science.gov (United States)

    Tsai, Christina; Yeh, Ting-Gu

    2017-04-01

    Extreme weather events are occurring more frequently as a result of climate change. Recently dengue fever has become a serious issue in southern Taiwan. It may have characteristic temporal scales that can be identified. Some researchers have hypothesized that dengue fever incidences are related to climate change. This study applies time-frequency analysis to time series data concerning dengue fever and hydrologic and meteorological variables. Results of three time-frequency analytical methods - the Hilbert Huang transform (HHT), the Wavelet Transform (WT) and the Short Time Fourier Transform (STFT) are compared and discussed. A more effective time-frequency analysis method will be identified to analyze relevant time series data. The most influential time scales of hydrologic and meteorological variables that are associated with dengue fever are determined. Finally, the linkage between hydrologic/meteorological factors and dengue fever incidences can be established.

  20. The impact of a program for strengthening dengue hemorrhagic fever case management on the clinical outcome of dengue hemorrhagic fever patients.

    Science.gov (United States)

    Mayurasakorn, Saengdao; Suttipun, Nipar

    2010-07-01

    This study compared the case fatality ratio (CFR) of dengue shock syndrome (DSS) patients admitted to Buri Ram Hospital, an area with CFR of 0.11, 0.43 and 0.23% in 2002, 2003 and 2004, respectively, to obtain a provincial model for dengue case management using the I. development of a special program for strengthening dengue hemorrhagic fever (DHF) case management (No deaths in DSS patients), II. a retrospective review of the medical records of dengue fever (DF), DHF and DSS patients referred to Buri Ram Hospital. We compared the data during the 3 periods of the implementation of this program. Data was statistically analyzed using chi2 or Fisher's exact test for categorical variables, one-way ANOVA for continuous data with normal distribution and Kruskal-Wallis test for nonparametric variables. The numbers of DF, DHF and DSS cases in Buri Ram were 1332, 1700 and 1630 person, respectively, during 2006-2008. The number of DSS patients increased after implementation of the program: 12.2, 51.2 and 47.22 for 2006, 2007 and 2008, respectively, but the complications of the disease decreased. The CFR during 2006, 2007 and 2008 were 0.15, 0 and 0.06% (p > 0.05). The program for strengthening DHF case management did improve clinical outcomes in dengue patients after the implementation. The CFR in 2008 was only 0.06%, lower than the goal of the Ministry of Public Health (<0.13%). This program is still running, sustaining low CFR in dengue patients. It may be used as a model for other provinces in Thailand that have high dengue deaths.

  1. Dengue and Severe Dengue

    Science.gov (United States)

    ... 686kB World Health Day 2014: Protect yourself from vector-borne diseases WHO's work on dengue Dengue (Special Programme for Research and Training in Tropical Diseases, TDR) Dengue vaccine development More about dengue Zika virus and potential complications Latest outbreaks Dengue Fever – ...

  2. Climate Variability and Dengue Hemorrhagic Fever in Ba Tri District, Ben Tre Province, Vietnam during 2004–2014

    Directory of Open Access Journals (Sweden)

    Le Thi Diem Phuong

    2016-09-01

    Full Text Available "Background: Currently, dengue fever/dengue hemorrhagic fever (DF/DHF is an important public health challenge in many areas, including the Ba Tri District, Ben Tre Province, Vietnam. Methods and Aim: This study was conducted in 2015 using a retrospective secondary data analysis on monthly data of DF/DHF cases and climate conditions from 2004–2014 in Ba Tri District, which aimed to explore the relationship between DF/DHF and climate variables. Results: During the period of 2004–2014, there were 5728 reported DF/DHF cases and five deaths. The disease occurred year round, with peaked from May to October and the highest number of cases occurred in June and July. There were strong correlations between monthly DF/DHF cases within that period with average rainfall (r = 0.70, humidity (r = 0.59, mosquito density (r = 0.82, and Breteau index (r = 0.81. A moderate association was observed between the monthly average number of DF/DHF cases and the average temperature (r = 0.37. The monthly DF/DHF cases were also moderately correlated with the Aedes mosquito density. Conclusions and Recommendations: Local health authorities need to monitor DF/DHF cases at the beginning of epidemic period, starting from April and to apply timely disease prevention measures to avoid the spreading of the disease in the following months. More vector control efforts should be implemented in March and April, just before the rainy season, which can help to reduce the vectordensity and the epidemic risk. A larger scale study using national data and for a longer period of time should be undertaken to thoroughly describe the correlation between climate variability and DF/DHF cases as well as for modeling and building projection model for the disease in the coming years. This can play an important role for active prevention of DF/DHF in Vietnam under the impacts of climate change and weather variability."

  3. Death by dengue fever in a Brazilian child: a case report.

    Science.gov (United States)

    Sacramento, Rafael Henrique Machado; de Melo Braga, Deborah Nunes; Sacramento, Franciane Fardin; de Carvalho Araújo, Fernanda Montenegro; Lima, Antônio Afonso Bezerra; de Lima Pompeu, Margarida Maria; Lima, Danielle Malta; de Góes Cavalcanti, Luciano Pamplona

    2014-11-27

    Dengue is an important worldwide public health problem, and continues to spread in Brazil. This article presents the first Brazilian case report of the death of an indigenous child by dengue fever. In August 2013, a child aged 2 years and from the Tremembé ethnic group, who was previously healthy with no complaints, suddenly presented intense crying, precordial pain, and general malaise. A few minutes after these non-specific symptoms, the patient started tonic-clonic convulsions and had cyanosis, a substantial increase in body temperature to the touch, cold sudoresis, sphincter relaxation, and unconsciousness. This situation remained for 15 minutes, progressing to respiratory insufficiency, with consequent absence of peripheral pulses. Death was confirmed approximately 40 minutes after the first symptoms. An autopsy was performed using the usual techniques. Immunohistochemistry was positive for dengue, and microscopic examination indicated micro perivascular edema and cerebral hemorrhage. Considering that the death occurred during the major endemic seasonal period for dengue fever, primary clinical evidence suggestive of viral infection presenting with sudden and quick death, and positive immunohistochemistry results, the case was closed as severe dengue fever. Clinicians must consider dengue as a diagnostic hypothesis among the indigenous population in Brazil.

  4. Direct Medical Costs of Dengue Fever in Vietnam: A Retrospective Study in a Tertiary Hospital.

    Science.gov (United States)

    Vo, Nhung Thi Tuyet; Phan, Trang Ngo Diem; Vo, Trung Quang

    2017-05-01

    In Vietnam, dengue fever is a major health concern, yet comprehensive information on its economic costs is lacking. The present study investigated treatment costs associated with dengue fever from the perspective of health care provision. This retrospective study was conducted between January 2013 and December 2015 in Cu Chi General Hospital. The following dengue-related treatment costs were calculated: hospitalisation, diagnosis, specialised services, drug usage and medical supplies. Average cost per case and treatment cost across different age was calculated. In the study period, 1672 patients with dengue fever were hospitalised. The average age was 24.98 (SD = 14.10) years, and 47.5% were males (795 patients). Across age groups, the average cost per episode was USD 48.10 (SD = 3.22). The highest costs (USD 56.61, SD = 48.84) were incurred in the adult age group (> 15 years), and the lowest costs (USD 30.10, SD = 17.27) were incurred in the paediatric age group (< 15 years). The direct medical costs of dengue-related hospitalisation place a severe economic burden on patients and their families. The probable economic value of dengue management in Vietnam is significant.

  5. The hidden passenger of Lucky bamboo: Do imported Aedes albopictus mosquitoes cause Dengue virus transmission in the Netherlands?

    NARCIS (Netherlands)

    Hofhuis, A.; Reimerink, J.; Reusken, C.; Scholte, E.J.; Boer, de A.; Takken, W.; Koopmans, M.P.G.

    2009-01-01

    Since 2005, Aedes albopictus mosquitoes have been detected in companies in the Netherlands that import ornamental plants from China. To assess the risks of dengue transmission, a study was carried out in 48 persons who are professionally exposed to these mosquitoes. No evidence for

  6. The hidden passenger of Lucky bamboo: Do imported Aedes albopictus mosquitoes cause Dengue virus transmission in the Netherlands?

    NARCIS (Netherlands)

    Hofhuis, A.; Reimerink, J.; Reusken, C.; Scholte, E.J.; Boer, de A.; Takken, W.; Koopmans, M.P.G.

    2009-01-01

    Since 2005, Aedes albopictus mosquitoes have been detected in companies in the Netherlands that import ornamental plants from China. To assess the risks of dengue transmission, a study was carried out in 48 persons who are professionally exposed to these mosquitoes. No evidence for non-travel-relate

  7. The hidden passenger of Lucky bamboo: Do imported Aedes albopictus mosquitoes cause Dengue virus transmission in the Netherlands?

    NARCIS (Netherlands)

    Hofhuis, A.; Reimerink, J.; Reusken, C.; Scholte, E.J.; Boer, de A.; Takken, W.; Koopmans, M.P.G.

    2009-01-01

    Since 2005, Aedes albopictus mosquitoes have been detected in companies in the Netherlands that import ornamental plants from China. To assess the risks of dengue transmission, a study was carried out in 48 persons who are professionally exposed to these mosquitoes. No evidence for non-travel-relate

  8. Dengue fever in renal transplant patients: a systematic review of literature.

    Science.gov (United States)

    Weerakkody, Ranga Migara; Patrick, Jean Ansbel; Sheriff, Mohammed Hussain Rezvi

    2017-01-13

    Dengue fever in renal transplanted patients has not been studied well, and we review all the literature about episodes dengue fever in renal transplant patients. The aim was to describe clinico-pathological characteristics, immunosuppressive protocols, need renal outcome and mortality. PubMed, LILACS, Google Scholar and Research Gate were searched for "Dengue" and "Renal/Kidney Transplantation" with no date limits. Hits were analyzed by two researchers separately. Fever, myalgia, arthralgia and headache was significantly lower than normal population, while pleural effusions and ascites were observed more. Incidence of severe dengue is significantly higher among transplant patients in this review, as well as they had a significantly higher mortality (8.9% vs 3.7%, p = 0.031). Age, period after transplantation and immunosuppressive profile had no effect on disease severity, mortality or graft out come. Presence of new bleeding complications and ascites was associated with more severe disease (p dengue fever in renal transplanted patients differ from the general population. Some degree of graft dysfunction is common during the illness, but only a minority develops graft failure.

  9. IL-10 and socs3 Are Predictive Biomarkers of Dengue Hemorrhagic Fever

    Science.gov (United States)

    Estrada-Jiménez, Tania; Sedeño-Monge, Virginia; Moreno, Margarita; Manjarrez, María del Consuelo; González-Ochoa, Guadalupe; Millán-Pérez Peña, Lourdes

    2017-01-01

    Background Cytokines play important roles in the physiopathology of dengue infection; therefore, the suppressors of cytokine signaling (socs) that control the type and timing of cytokine functions could be involved in the origin of immune alterations in dengue. Objective To explore the association of cytokine and socs levels with disease severity in dengue patients. Methods Blood samples of 48 patients with confirmed dengue infection were analyzed. Amounts of interleukins IL-2, IL-4, IL-6, and IL-10, interferon- (IFN-) γ, and tumor necrosis factor- (TNF-) α were quantified by flow cytometry, and the relative expression of socs1 and socs3 mRNA was quantified by real-time RT-PCR. Results Increased levels of IL-10 and socs3 and lower expression of socs1 were found in patients with dengue hemorrhagic fever (DHF) with respect to those with dengue fever (DF) (p 199.8-fold), socs1 (134 pg/ml) have the highest sensitivity and specificity to discriminate between DF and DHF. Conclusion Simultaneous changes in IL-10 and socs1/socs3 could be used as prognostic biomarkers of dengue severity. PMID:28827898

  10. IL-10 and socs3 Are Predictive Biomarkers of Dengue Hemorrhagic Fever

    Directory of Open Access Journals (Sweden)

    Lilian Karem Flores-Mendoza

    2017-01-01

    Full Text Available Background. Cytokines play important roles in the physiopathology of dengue infection; therefore, the suppressors of cytokine signaling (socs that control the type and timing of cytokine functions could be involved in the origin of immune alterations in dengue. Objective. To explore the association of cytokine and socs levels with disease severity in dengue patients. Methods. Blood samples of 48 patients with confirmed dengue infection were analyzed. Amounts of interleukins IL-2, IL-4, IL-6, and IL-10, interferon- (IFN- γ, and tumor necrosis factor- (TNF- α were quantified by flow cytometry, and the relative expression of socs1 and socs3 mRNA was quantified by real-time RT-PCR. Results. Increased levels of IL-10 and socs3 and lower expression of socs1 were found in patients with dengue hemorrhagic fever (DHF with respect to those with dengue fever (DF (p199.8-fold, socs1 (134 pg/ml have the highest sensitivity and specificity to discriminate between DF and DHF. Conclusion. Simultaneous changes in IL-10 and socs1/socs3 could be used as prognostic biomarkers of dengue severity.

  11. Central retinal vein occlusion concomitant with dengue fever

    OpenAIRE

    Velaitham, Punithamalar; Vijayasingham, Nandini

    2016-01-01

    Background Dengue virus infection is on the rise and there is increasing number of ocular complications that are being reported. Most common ocular complications are macular edema, macular hemorrhages, and foveolitis. There are case reports on branch retinal vessel occlusions. Most of the ocular complications are attributed to the bleeding tendency and transudative process in dengue viral infection. This is a case report of ischemic central retinal vein occlusion (CRVO) concomitant with dengu...

  12. Central retinal vein occlusion concomitant with dengue fever

    OpenAIRE

    Velaitham, Punithamalar; Vijayasingham, Nandini

    2016-01-01

    Background Dengue virus infection is on the rise and there is increasing number of ocular complications that are being reported. Most common ocular complications are macular edema, macular hemorrhages, and foveolitis. There are case reports on branch retinal vessel occlusions. Most of the ocular complications are attributed to the bleeding tendency and transudative process in dengue viral infection. This is a case report of ischemic central retinal vein occlusion (CRVO) concomitant with dengu...

  13. An unusual ocular emergency in severe dengue

    Directory of Open Access Journals (Sweden)

    Kalpana Badami Nagaraj

    2014-01-01

    Full Text Available 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.

  14. Scanning electron microscopy of damage caused by Mesocyclops thermocyclopoides (Copepoda: Cyclopoidea on larvae of the Dengue fever vector Aedes aegypti (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    Stefan Schaper

    2006-09-01

    Full Text Available Dengue fever is a mosquito-borne viral disease, whose main biological vector is Aedes aegypti. This mosquito colonizes tropical areas where the disease is endemic. The most obvious action against dengue is attacking its vector. Biological control appears to be an alternative approach, using natural enemies of the mosquitoes, such as predatory copepods. Thus, the morphological study of the damage caused by copepods is important to understand its predatory capacity. Twenty-five A. aegypti larvae were exposed to the copepod Mesocyclops thermocyclopoides and the damage caused by the copepods was evaluated using scanning electron microscopy. The larvae showed damage mainly at the anal segment, the siphon and the abdomen; only three attacks to the head were observed. The size of the siphon might be of importance in determining whether or not a copepod will attack a mosquito larva. Rev. Biol. Trop. 54 (3: 843-846. Epub 2006 Sept. 29.El dengue es una enfermedad viral transmitida por mosquitos, cuyo principal vector es Aedes aegypti. Este mosquito coloniza muchas áreas tropicales donde la enfermedad es endémica. La acción más obvia contra el dengue es el ataque a su vector. El control biológico parece una buena alternativa, empleando enemigos naturales de los mosquitos, como los copépodos. Por lo tanto, es importante el estudio morfológico del daño causado por los copépodos para comprender su capacidad depredadora. Veinticinco larvas de A. aegypti fueron expuestas a la actividad depredadora del copépodo Mesocyclops thermocyclopoides. Mediante microscopia electrónica de rastreo se evaluó el daño causado por los copépodos. Éstos atacaron principalmente el segmento anal, el sifón y el abdomen de las larvas; sólo vimos tres ataques a la cabeza. El tamaño del sifón podría ser de importancia para predecir si los copépodos pudiesen atacar larvas de determinado mosquito.

  15. Culture proven Salmonella typhi co-infection in a child with Dengue fever: a case report.

    Science.gov (United States)

    Srinivasaraghavan, Rangan; Narayanan, Parameswaran; Kanimozhi, Thandapani

    2015-09-27

    Infectious diseases are one of the major causes of morbidity and mortality in developing countries. Sometimes concurrent infections with multiple infectious agents may occur in one patient, which make the diagnosis and management a challenging task. The authors here present a case of co-infection of typhoid fever with dengue fever in a ten-year-old child and discuss the pertinent issues. The authors emphasize that the risk factors predicting the presence of such co-infections, if developed, will be immensely useful in areas where dengue outbreak occurs in the background of high transmission of endemic infections.

  16. CD8+T Lymphocyte Expansion, Proliferation and Activation in Dengue Fever

    OpenAIRE

    Andréia Manso de Matos; Karina Inacio Carvalho; Daniela Santoro Rosa; Lucy Santos Villas-Boas; Wanessa Cardoso da Silva; Célia Luiza de Lima Rodrigues; Olímpia Massae Nakasone Peel Furtado Oliveira; José Eduardo Levi; Evaldo Stanislau Affonso de Araújo; Claudio Sergio Pannuti; Expedito José Albuquerque Luna; Esper George Kallas

    2015-01-01

    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 m...

  17. ROLE OF PLATELET TRANSFUSIONS IN DENGUE HEMORRHAGIC FEVER- 6 MONTHS REPORT

    Directory of Open Access Journals (Sweden)

    Geeta

    2012-08-01

    Full Text Available ABSTRACT: BACKGROUND: Allogenic platelet transfusion plays a major role in the management of thrombocytopenia. The study includes details of pla telet transfusion over a period of 6 months from January-2011 to June-2011 at blood bank of Gan dhi Hospital. Total number of patients who received were 487 and proportionate use of total un its of RDP (Random Donor Platelets issued from blood bank were as follows; dengue hemorrhagic fever (38% and remaining for acute leukemia (12%, Aplastic anemia (10%, sepsis (10% , DIC (Disseminated Intravascular Coagulation (10%, cardiac surgery (10%. In dengu e hemorrhagic fever, correlation of platelet count with platelet transfusion and platelet increm ent have been evaluated.

  18. Socially structured human movement shapes dengue transmission despite the diffusive effect of mosquito dispersal

    Directory of Open Access Journals (Sweden)

    Robert C. Reiner, Jr.

    2014-03-01

    Full Text Available 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.

  19. Nationwide study of factors associated with public's willingness to use home self-test kit for dengue fever in Malaysia.

    Science.gov (United States)

    Wong, Li Ping; Atefi, Narges; AbuBakar, Sazaly

    2016-08-12

    As there is no specific treatment for dengue, early detection and access to proper treatment may lower dengue fatality. Therefore, having new techniques for the early detection of dengue fever, such as the use of dengue test kit, is vitally important. The aims of the study were: 1) identify factors associated with acceptance of a home self-test kit for dengue fever if the dengue test is available to the public and 2) find out the characteristics of the test kits that influence the use of the dengue test kit. A national telephone survey was carried out with 2,512 individuals of the Malaysian public aged 18-60 years old. Individuals were contacted by random digit dialling covering the whole of Malaysia from February 2012 to June 2013. From 2,512 participants, 6.1 % reported to have heard of the availability of the dengue home test kit and of these, 44.8 % expressed their intention to use the test kit if it was available. Multivariate logistic regressions indicated that participants with primary (OR: 0.65; 95 % CI: 0.43-0.89; p = 0.02, vs. tertiary educational level) and secondary educational levels (OR: 0.73; 95 % CI: 0.57-0.90; p = 0.01, vs. tertiary educational level) were less likely than participants with a tertiary educational level to use a home self-testing dengue kit for dengue if the kit was available. Participants with lower perceived barriers to dengue prevention (level of barriers 0-5) were less likely (OR: 0.67, 95 % CI: 0.53-0.85, p dengue fever knowledge score (range 0-22) were also less likely to use a home self-testing dengue kit for dengue if the kit was available (OR: 0.75; 95 % CI: 0.61-0.91, p = 0.001, vs. higher total dengue fever knowledge score) compared to those with a higher total dengue fever knowledge score (range 23-44). With response to characteristics of the test kit, participants indicated that ease of usability and easy to understand instructions were the most important factors influencing the decision to use the

  20. Serum Metabolomics Reveals Serotonin as a Predictor of Severe Dengue in the Early Phase of Dengue Fever.

    Science.gov (United States)

    Cui, Liang; Lee, Yie Hou; Thein, Tun Linn; Fang, Jinling; Pang, Junxiong; Ooi, Eng Eong; Leo, Yee Sin; Ong, Choon Nam; Tannenbaum, Steven R

    2016-04-01

    Effective triage of dengue patients early in the disease course for in- or out-patient management would be useful for optimal healthcare resource utilization while minimizing poor clinical outcome due to delayed intervention. Yet, early prognosis of severe dengue is hampered by the heterogeneity in clinical presentation and routine hematological and biochemical measurements in dengue patients that collectively correlates poorly with eventual clinical outcome. Herein, untargeted liquid-chromatography mass spectrometry metabolomics of serum from patients with dengue fever (DF) and dengue hemorrhagic fever (DHF) in the febrile phase (1.5) in the serum, among which are two products of tryptophan metabolism-serotonin and kynurenine. Serotonin, involved in platelet aggregation and activation decreased significantly, whereas kynurenine, an immunomodulator, increased significantly in patients with DHF, consistent with thrombocytopenia and immunopathology in severe dengue. To sensitively and accurately evaluate serotonin levels as prognostic biomarkers, we implemented stable-isotope dilution mass spectrometry and used convalescence samples as their own controls. DHF serotonin was significantly 1.98 fold lower in febrile compared to convalescence phase, and significantly 1.76 fold lower compared to DF in the febrile phase of illness. Thus, serotonin alone provided good prognostic utility (Area Under Curve, AUC of serotonin = 0.8). Additionally, immune mediators associated with DHF may further increase the predictive ability than just serotonin alone. Nine cytokines, including IFN-γ, IL-1β, IL-4, IL-8, G-CSF, MIP-1β, FGF basic, TNFα and RANTES were significantly different between DF and DHF, among which IFN-γ ranked top by multivariate statistics. Combining serotonin and IFN-γ improved the prognosis performance (AUC = 0.92, sensitivity = 77.8%, specificity = 95.8%), suggesting this duplex panel as accurate metrics for the early prognosis of DHF.

  1. Dengue and dengue hemorrhagic fever epidemics in Brazil: what research is needed based on trends, surveillance, and control experiences?

    Directory of Open Access Journals (Sweden)

    Teixeira Maria da Glória

    2005-01-01

    Full Text Available Dengue epidemics account annually for several million cases and deaths worldwide. The high endemic level of dengue fever and its hemorrhagic form correlates to extensive domiciliary infestation by Aedes aegypti and multiple viral serotype human infection. This study analyzed serial case reports registered in Brazil since 1981, describing incidence evolutionary patterns and spatial distribution. Epidemic waves followed the introduction of every serotype (DEN 1 to 3, and reduction in susceptible individuals possibly accounted for decreasing case frequency. An incremental expansion of affected areas and increasing occurrence of dengue fever and its hemorrhagic form with high case fatality were noted in recent years. In contrast, efforts based solely on chemical vector control have been insufficient. Moreover, some evidence demonstrates that educational measures do not permanently modify population habits. Thus, as long as a vaccine is not available, further dengue control depends on potential results from basic interdisciplinary research and intervention evaluation studies, integrating environmental changes, community participation and education, epidemiological and virological surveillance, and strategic technological innovations aimed to stop transmission.

  2. Dengue and dengue hemorrhagic fever epidemics in Brazil: what research is needed based on trends, surveillance, and control experiences?

    Directory of Open Access Journals (Sweden)

    Maria da Glória Teixeira

    Full Text Available Dengue epidemics account annually for several million cases and deaths worldwide. The high endemic level of dengue fever and its hemorrhagic form correlates to extensive domiciliary infestation by Aedes aegypti and multiple viral serotype human infection. This study analyzed serial case reports registered in Brazil since 1981, describing incidence evolutionary patterns and spatial distribution. Epidemic waves followed the introduction of every serotype (DEN 1 to 3, and reduction in susceptible individuals possibly accounted for decreasing case frequency. An incremental expansion of affected areas and increasing occurrence of dengue fever and its hemorrhagic form with high case fatality were noted in recent years. In contrast, efforts based solely on chemical vector control have been insufficient. Moreover, some evidence demonstrates that educational measures do not permanently modify population habits. Thus, as long as a vaccine is not available, further dengue control depends on potential results from basic interdisciplinary research and intervention evaluation studies, integrating environmental changes, community participation and education, epidemiological and virological surveillance, and strategic technological innovations aimed to stop transmission.

  3. Dengue and Chikungunya fever among viral diseases in outpatient febrile children in Kilosa district hospital, Tanzania.

    Science.gov (United States)

    Chipwaza, Beatrice; Mugasa, Joseph P; Selemani, Majige; Amuri, Mbaraka; Mosha, Fausta; Ngatunga, Steve D; Gwakisa, Paul S

    2014-11-01

    Viral etiologies of fever, including dengue, Chikungunya, influenza, rota and adeno viruses, cause major disease burden in tropical and subtropical countries. The lack of diagnostic facilities in developing countries leads to failure to estimate the true burden of such illnesses, and generally the diseases are underreported. These diseases may have similar symptoms with other causes of acute febrile illnesses including malaria and hence clinical diagnosis without laboratory tests can be difficult. This study aimed to identify viral etiologies as a cause of fever in children and their co-infections with malaria. A cross sectional study was conducted for 6 months at Kilosa district hospital, Tanzania. The participants were febrile children aged 2-13 years presented at the outpatient department. Diagnostic tests such as IgM and IgG ELISA, and PCR were used. A total of 364 patients were enrolled, of these 83(22.8%) had malaria parasites, 76 (20.9%) had presumptive acute dengue infection and among those, 29(38.2%) were confirmed cases. Dengue was more likely to occur in children ≥ 5 years than in dengue infection or malaria. Co-infections between malaria and Chikungunya, malaria and dengue fever as well as Chikungunya and dengue were detected. Most patients with Chikungunya and dengue infections were treated with antibacterials. Furthermore, our results revealed that 5(5.2%) of patients had influenza virus while 5(12.8%) had rotavirus and 2(5.1%) had adenovirus. Our results suggest that even though viral diseases are a major public health concern, they are not given due recognition as a cause of fever in febrile patients. Emphasis on laboratory diagnostic tests for proper diagnosis and management of febrile patients is recommended.

  4. Ludwig's angina after severe thrombocytopenic purpura associated with dengue fever

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    Maria Antonia Campos

    2014-01-01

    Full Text Available Here, we report a case of Ludwig's angina, which required surgery because of toothache. The patient had dengue and severe thrombocytopenia as confirmed by clinical and laboratory diagnoses. However, dengue is not included among the predisposing factors for Ludwig's angina.

  5. Environmental and Socio-Demographic Determinants of Dengue Fever in Colombo City, Sri Lanka

    Science.gov (United States)

    Tipre, Meghan; Luvall, Jeffrey; Haque, Akhlaque; McClure, Leslie; Zaitchik, Ben; Sathiakumar, Nalini

    2014-01-01

    Dengue fever has increased exponentially in Sri Lanka, from 24.4 cases per 100,000 in 2003 to 165.3 per 100,000 population in 2013. Although early warning systems using predictor models have been previously developed in other settings, it is important to develop such models in each local setting. Further, the ability of these models to be applicable at smaller geographic units will enhance current vector control and disease surveillance measures. The aim of this paper was to identify environmental and socio-economic status (SES) risk factors that may predict dengue fever at the Gram Niladhari Divisions (GND) level (smallest administrative unit) in Colombo city, Sri Lanka. These factors included landcover classes, amount of vegetation, population density, water access and neighborhood SES as determined by roof type. A geographically weighted regression (GWR) was used to develop the prediction model. A total 55 GND units covering an area of 37 sq km were investigated. We found that GND units with decreased vegetation, higher built-up area, higher population density and poor access to tap-water supply were associated with high risk of dengue; the pertinent GND units were concentrated in the center of the city. This is the first study in Sri Lanka to include both environmental and socio-demographic factors in prediction models for dengue fever. The methodology may be useful in enhancing ongoing dengue fever control measures in the country, and to be extended to other countries in the region that have an increasing incidence of dengue fever.

  6. Clinical significance of skin rash in dengue fever: A focus on discomfort, complications, and disease outcome.

    Science.gov (United States)

    Huang, Hsin-Wei; Tseng, Han-Chi; Lee, Chih-Hung; Chuang, Hung-Yi; Lin, Shang-Hung

    2016-07-01

    To assess whether the cutaneous features in patients with dengue fever are associated with abnormal blood biochemistry, complications, and poor disease outcome. Forty five patients with dengue fever were identified at a medical center in Kaohsiung, Taiwan, from September to November 2014. All cases were exclusively caused by type 1 dengue virus. Patients were classified into two groups, based on the presence or absence of skin rash, and their rash was subclassified into maculopapular, morbilliform, and petechial types. Clinical symptoms, laboratory data, disease outcome, and complications were compared between the two groups. Thirty two patients with dengue fever developed skin rash (SP group, n = 32) while the rest of 13 did not (SN group, n = 13). The patient numbers in the maculopapular, morbilliform, and petechial group were 4, 21, and 7, respectively. The SP group was younger (P = 0.001), experienced more pruritus (P = 0.008) and more swollen palms/soles (P = 0.015) than the SN group. However, the SN group had greater genital mucosa involvement (P = 0.008), higher platelet transfusion rate (P = 0.003), and lower hemoglobin and hematocrit levels (P = 0.030) than the SP group. Patients with morbilliform lesions had a higher incidence of palm/sole swelling, less genital mucosal involvement, and a lower platelet transfusion rate than did patients with maculopapular or petechial lesions. Cutaneous manifestations provide an important clue to dengue fever. In patients with dengue fever, those with skin rash tend to have itching and swelling of the palms/soles, however, those without skin rash tend to have more complications and poor disease outcomes. Copyright © 2016 Hainan Medical College. Production and hosting by Elsevier B.V. All rights reserved.

  7. Ultrasonography as a tool in predicting the severity of dengue fever in children--a useful aid in a developing country.

    Science.gov (United States)

    Bharath Kumar Reddy, K R; Laksmana, Ramesh R; Veerappa, Basavaraja G; Shivananda

    2013-08-01

    Dengue fever accounts for significant mortality in developing countries. Dengue fever serology takes a week at least to be reported positive, thus necessitating the need for other markers of diagnosis and prognosis. The purpose of this study was to investigate the role of ultrasonography as a tool in diagnosing and predicting the severity of dengue fever in children. This was a prospective study conducted in a tertiary pediatric centre from September 2010 to July 2012. Three hundred twenty-four children with confirmed dengue fever were compared with 422 children of suspected dengue fever. Severity of illness was graded as per WHO criteria and sonography findings were correlated to the grade of illness. Gallbladder wall thickening was seen in 75% of the children with confirmed dengue fever. A significant difference was seen between survivors and non-survivors with respect to pericholecystic fluid collection (P = 0.002), hepatic intraparenchymal fluid (P dengue fever in children.

  8. Detection of circulant tumor necrosis factor-alpha , soluble tumor necrosis factor p75 and interferon-gamma in Brazilian patients with dengue fever and dengue hemorrhagic fever

    Directory of Open Access Journals (Sweden)

    Elzinandes LA Braga

    2001-02-01

    Full Text Available Pro-inflammatory cytokines are believed to play an important role in the pathogenesis of dengue infection. This study reports cytokine levels in a total of 54 patients examined in Recife, State of Pernambuco, Brazil. Five out of eight patients who had hemorrhagic manifestations presented tumor necrosis factor-alpha (TNF-alpha levels in sera which were statistically higher than those recorded for controls. In contrast, only one out of 16 patients with mild manifestations had elevated TNF-alpha levels. The levels of interleukin-6 (IL, IL-1beta tested in 24 samples and IL-12 in 30 samples were not significantly increased. Interferon-g was present in 10 out of 30 patients with dengue. The data support the concept that the increased level of TNF-alpha is related to the severity of the disease. Soluble TNF receptor p75 was found in most patients but it is unlikely to be related to severity since it was found with an equivalent frequency and levels in 15 patients with dengue fever and another 15 with dengue hemorrhagic fever.

  9. Chimeric Yellow Fever/Dengue Virus as a Candidate Dengue Vaccine: Quantitation of the Dengue Virus-Specific CD8 T-Cell Response

    OpenAIRE

    van der Most, Robbert G.; Murali-Krishna, Kaja; Ahmed, Rafi; Strauss, James H.

    2000-01-01

    We have constructed a chimeric yellow fever/dengue (YF/DEN) virus, which expresses the premembrane (prM) and envelope (E) genes from DEN type 2 (DEN-2) virus in a YF virus (YFV-17D) genetic background. Immunization of BALB/c mice with this chimeric virus induced a CD8 T-cell response specific for the DEN-2 virus prM and E proteins. This response protected YF/DEN virus-immunized mice against lethal dengue encephalitis. Control mice immunized with the parental YFV-17D were not protected against...

  10. Dengue fever occurrence and vector detection by larval survey, ovitrap and MosquiTRAP: a space-time clusters analysis.

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

  12. Dengue fever occurrence and vector detection by larval survey, ovitrap and MosquiTRAP: a space-time clusters analysis.

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    Diogo Portella Ornelas de Melo

    Full Text Available 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.

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

    Science.gov (United States)

    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.

  14. Dengue virus type 2 infections of Aedes aegypti are modulated by the mosquito's RNA interference pathway.

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    Irma Sánchez-Vargas

    2009-02-01

    Full Text Available A number of studies have shown that both innate and adaptive immune defense mechanisms greatly influence the course of human dengue virus (DENV infections, but little is known about the innate immune response of the mosquito vector Aedes aegypti to arbovirus infection. We present evidence here that a major component of the mosquito innate immune response, RNA interference (RNAi, is an important modulator of mosquito infections. The RNAi response is triggered by double-stranded RNA (dsRNA, which occurs in the cytoplasm as a result of positive-sense RNA virus infection, leading to production of small interfering RNAs (siRNAs. These siRNAs are instrumental in degradation of viral mRNA with sequence homology to the dsRNA trigger and thereby inhibition of virus replication. We show that although dengue virus type 2 (DENV2 infection of Ae. aegypti cultured cells and oral infection of adult mosquitoes generated dsRNA and production of DENV2-specific siRNAs, virus replication and release of infectious virus persisted, suggesting viral circumvention of RNAi. We also show that DENV2 does not completely evade RNAi, since impairing the pathway by silencing expression of dcr2, r2d2, or ago2, genes encoding important sensor and effector proteins in the RNAi pathway, increased virus replication in the vector and decreased the extrinsic incubation period required for virus transmission. Our findings indicate a major role for RNAi as a determinant of DENV transmission by Ae. aegypti.

  15. Spatial mapping of gene expression in the salivary glands of the dengue vector mosquito, aedes aegypti

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    Paolucci Pimenta Paulo

    2011-01-01

    Full Text Available Abstract Background Aedes aegypti mosquitoes are the main vectors of dengue viruses to humans. Understanding their biology and interactions with the pathogen are prerequisites for development of dengue transmission control strategies. Mosquito salivary glands are organs involved directly in pathogen transmission to vertebrate hosts. Information on the spatial distribution of gene expression in these organs is expected to assist in the development of novel disease control strategies, including those that entail the release of transgenic mosquitoes with impaired vector competence. Results We report here the hybridization in situ patterns of 30 transcripts expressed in the salivary glands of adult Ae. aegypti females. Distinct spatial accumulation patterns were identified. The products of twelve genes are localized exclusively in the proximal-lateral lobes. Among these, three accumulate preferentially in the most anterior portion of the proximal-lateral lobe. This pattern revealed a salivary gland cell type previously undescribed in Ae. aegypti, which was validated by transmission electron microscopy. Five distinct gene products accumulate in the distal-lateral lobes and another five localize in the medial lobe. Seven transcripts are found in the distal-lateral and medial lobes. The transcriptional product of one gene accumulates in proximal- and distal-lateral lobes. Seven genes analyzed by quantitative PCR are expressed constitutively. The most abundant salivary gland transcripts are those localized within the proximal-lateral lobes, while previous work has shown that the distal-lateral lobes are the most active in protein synthesis. This incongruity suggests a role for translational regulation in mosquito saliva production. Conclusions Transgenic mosquitoes with reduced vector competence have been proposed as tools for the control of dengue virus transmission. Expression of anti-dengue effector molecules in the distal-lateral lobes of Ae

  16. Dengue virus: A global human threat: Review of literature

    OpenAIRE

    Hasan, Shamimul; Jamdar, Sami Faisal; Alalowi, Munther; Al Ageel Al Beaiji, Sadun Mohammad

    2016-01-01

    Dengue is an acute viral illness caused by RNA virus of the family Flaviviridae and spread by Aedes mosquitoes. Presenting features may range from asymptomatic fever to dreaded complications such as hemorrhagic fever and shock. A cute-onset high fever, muscle and joint pain, myalgia, cutaneous rash, hemorrhagic episodes, and circulatory shock are the commonly seen symptoms. Oral manifestations are rare in dengue infection; however, some cases may have oral features as the only presenting mani...

  17. Use of a tandem affinity purification assay to detect interactions between West Nile and dengue viral proteins and proteins of the mosquito vector.

    Science.gov (United States)

    Colpitts, Tonya M; Cox, Jonathan; Nguyen, Annie; Feitosa, Fabiana; Krishnan, Manoj N; Fikrig, Erol

    2011-08-15

    West Nile and dengue viruses are (re)emerging mosquito-borne flaviviruses that cause significant morbidity and mortality in man. The identification of mosquito proteins that associate with flaviviruses may provide novel targets to inhibit infection of the vector or block transmission to humans. Here, a tandem affinity purification (TAP) assay was used to identify 18 mosquito proteins that interact with dengue and West Nile capsid, envelope, NS2A or NS2B proteins. We further analyzed the interaction of mosquito cadherin with dengue and West Nile virus envelope protein using co-immunoprecipitation and immunofluorescence. Blocking the function of select mosquito factors, including actin, myosin, PI3-kinase and myosin light chain kinase, reduced both dengue and West Nile virus infection in mosquito cells. We show that the TAP method may be used in insect cells to accurately identify flaviviral-host protein interactions. Our data also provides several targets for interrupting flavivirus infection in mosquito vectors.

  18. Insilico modeling of Wolbachia and its potentials in combating mosquito borne diseases Chikungunya and Dengue

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    N.M.Guruprasad

    2013-09-01

    Full Text Available Mosquito borne diseases are major health burden both in tropical and subtropical regions. The enormous use of insecticides to control mosquitoes causes biomagnification of chemicals in environment and mosquitoes have developed resistance to insecticides. The inefficiency of insecticides to combat mosquitoes prompted researchers to develop efficient alternative methods. Wolbachia endosymbiont is a one of efficient new approach to control mosquitoes. Wolbachia strain invade mosquitoes biology by reducing host lifespan, phenotype and inhibit virus replication. In the present study, insilico modeling and docking of Wolbachia and human pathogens Chikungunya (CHIK and Dengue (DEN virus was done. Docking is the method to find the binding affinity of protein and ligand complex molecules for finding potential inhibitor. Using Hex, we obtained energy total (e-total values in kcal/mol for all docked complex. In the contest of overall analyzing the docking E-total values of docked complexes reveals that WSP-B has show strong binding affinity than WSP-A to both DEN and CHIK. Based on obtained result, we suggest WSP-B has potential inhibitor for both DEN and CHIK virus. Further, biophysical characterization of Wolbachia will help to develop a drug to combat CHIK and DEN viruses.

  19. How Important is Vertical Transmission of Dengue Viruses by Mosquitoes (Diptera: Culicidae)?

    Science.gov (United States)

    Grunnill, Martin; Boots, Michael

    2016-01-01

    Vertical transmission of dengue viruses by mosquitoes was discovered at the end of the late 1970s and has been suggested to be a means by which these viruses persist. However, it is unclear how widespread it is in nature, and its importance in the epidemiology of this disease is still debated. Here, we review the literature on vertical transmission and discuss its role in dengue's epidemiology and control. We conclude that given the number of studies that failed to find evidence of vertical transmission, as well as mathematical models and its mechanistic basis, it is unlikely that vertical transmission is important for the epidemiological persistence of dengue viruses. A combination of asymptomatic infection in humans and movement of people are likely to be more important determinants of dengue's persistence. We argue, however, that there may be some need for further research into the prevalence of dengue viruses in desiccated, as well as diapausing, eggs and the role of horizontal transmission through larval cannibalism.

  20. Dengue Hemorrhagic Fever Mapping: Study Case in Karawang District, West Java Indonesia

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    Tris Eryando

    2013-12-01

    Full Text Available The DHF prevention efforts have been continually conducted by the local health office, but some technical obstacles such as surveillance system is still very weak, and this is known as an important part in decision making process to handle the problem using evidence based information. The research objective is to obtain information on dengue endemic mapping through GIS (Geographic Information Systems to strengthen district surveillance system in district level. Most DHF cases occur in the productive age and located in urban areas with the larva-free rate is low. The direction of movement of the case are local diffusion. Karawang district is a low-lying areas prone to flooding. The rainy season occurs in late October to early May, but the rise of dengue cases at the turn of the rainy season to dry season, this indicates that the humidity in Karawang district supports the mosquito vector breeding. Foging will only kill adult mosquitoes, dengue control programs need to involve community participation and emphasized on public areas like schools and offices because a lot of dengue cases occurred in the productive age. GIS is capable of producing a map factors of risk and map of the case to allow for planning and evaluation of area-based dengue eradication program. GIS is useful in surveillance environmentally based disease, health interventions, and disease prevention strategies.

  1. Fever versus Fever: the role of host and vector susceptibility and interspecific competition in shaping the current and future distributions of the sylvatic cycles of dengue virus and yellow fever virus

    Science.gov (United States)

    Hanley, Kathryn A.; Monath, Thomas P.; Weaver, Scott C.; Rossi, Shannan L.; Richman, Rebecca L.; Vasilakis, Nikos

    2013-01-01

    Two different species of flaviviruses, dengue virus (DENV) and yellow fever virus (YFV), that originated in sylvatic cycles maintained in non-human primates and forest-dwelling mosquitoes have emerged repeatedly into sustained human-to-human transmission by Aedes aegypti mosquitoes. Sylvatic cycles of both viruses remain active, and where the two viruses overlap in West Africa they utilize similar suites of monkeys and Aedes mosquitoes. These extensive similarities render the differences in the biogeography and epidemiology of the two viruses all the more striking. First, the sylvatic cycle of YFV originated in Africa and was introduced into the New World, probably as a result of the slave trade, but is absent in Asia; in contrast, sylvatic DENV likely originated in Asia and has spread to Africa but not to the New World. Second, while sylvatic YFV can emerge into extensive urban outbreaks in humans, these invariably die out, whereas four different types of DENV have established human transmission cycles that are ecologically and evolutionarily distinct from their sylvatic ancestors. Finally, transmission of YFV among humans has been documented only in Africa and the Americas, whereas DENV is transmitted among humans across most of the range of competent Aedes vectors, which in the last decade has included every continent save Antarctica. This review summarizes current understanding of sylvatic transmission cycles of YFV and DENV, considers possible explanations for their disjunct distributions, and speculates on the potential consequences of future establishment of a sylvatic cycle of DENV in the Americas. PMID:23523817

  2. siRNA-Mediated Silencing of doublesex during Female Development of the Dengue Vector Mosquito Aedes aegypti.

    Science.gov (United States)

    Mysore, Keshava; Sun, Longhua; Tomchaney, Michael; Sullivan, Gwyneth; Adams, Haley; Piscoya, Andres S; Severson, David W; Syed, Zainulabeuddin; Duman-Scheel, Molly

    2015-11-01

    The development of sex-specific traits, including the female-specific ability to bite humans and vector disease, is critical for vector mosquito reproduction and pathogen transmission. Doublesex (Dsx), a terminal transcription factor in the sex determination pathway, is known to regulate sex-specific gene expression during development of the dengue fever vector mosquito Aedes aegypti. Here, the effects of developmental siRNA-mediated dsx silencing were assessed in adult females. Targeting of dsx during A. aegypti development resulted in decreased female wing size, a correlate for body size, which is typically larger in females. siRNA-mediated targeting of dsx also resulted in decreased length of the adult female proboscis. Although dsx silencing did not impact female membrane blood feeding or mating behavior in the laboratory, decreased fecundity and fertility correlated with decreased ovary length, ovariole length, and ovariole number in dsx knockdown females. Dsx silencing also resulted in disruption of olfactory system development, as evidenced by reduced length of the female antenna and maxillary palp and the sensilla present on these structures, as well as disrupted odorant receptor expression. Female lifespan, a critical component of the ability of A. aegypti to transmit pathogens, was also significantly reduced in adult females following developmental targeting of dsx. The results of this investigation demonstrate that silencing of dsx during A. aegypti development disrupts multiple sex-specific morphological, physiological, and behavioral traits of adult females, a number of which are directly or indirectly linked to mosquito reproduction and pathogen transmission. Moreover, the olfactory phenotypes observed connect Dsx to development of the olfactory system, suggesting that A. aegypti will be an excellent system in which to further assess the developmental genetics of sex-specific chemosensation.

  3. siRNA-Mediated Silencing of doublesex during Female Development of the Dengue Vector Mosquito Aedes aegypti.

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    Keshava Mysore

    2015-11-01

    Full Text Available The development of sex-specific traits, including the female-specific ability to bite humans and vector disease, is critical for vector mosquito reproduction and pathogen transmission. Doublesex (Dsx, a terminal transcription factor in the sex determination pathway, is known to regulate sex-specific gene expression during development of the dengue fever vector mosquito Aedes aegypti. Here, the effects of developmental siRNA-mediated dsx silencing were assessed in adult females. Targeting of dsx during A. aegypti development resulted in decreased female wing size, a correlate for body size, which is typically larger in females. siRNA-mediated targeting of dsx also resulted in decreased length of the adult female proboscis. Although dsx silencing did not impact female membrane blood feeding or mating behavior in the laboratory, decreased fecundity and fertility correlated with decreased ovary length, ovariole length, and ovariole number in dsx knockdown females. Dsx silencing also resulted in disruption of olfactory system development, as evidenced by reduced length of the female antenna and maxillary palp and the sensilla present on these structures, as well as disrupted odorant receptor expression. Female lifespan, a critical component of the ability of A. aegypti to transmit pathogens, was also significantly reduced in adult females following developmental targeting of dsx. The results of this investigation demonstrate that silencing of dsx during A. aegypti development disrupts multiple sex-specific morphological, physiological, and behavioral traits of adult females, a number of which are directly or indirectly linked to mosquito reproduction and pathogen transmission. Moreover, the olfactory phenotypes observed connect Dsx to development of the olfactory system, suggesting that A. aegypti will be an excellent system in which to further assess the developmental genetics of sex-specific chemosensation.

  4. Clinical Profile and Outcome in Children of Dengue Hemorrhagic Fever in North India

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    Deepak Bhat

    2008-09-01

    Full Text Available Objective: The number of dengue fever (DF/dengue hemorrhagic fever (DHF cases reported in India has risen in recent years. This study was undertaken to evaluate clinical profile and outcome of children admitted with DHF/dengue shock syndrome (DSS, in the 2006 DHF epidemic in Ludhiana, Punjab. Methods: Eighty one children with dengue hemorrhagic fever were hospitalized in the Pediatric Department of Dayanand Medical College and Hospital, Ludhiana, India. All patients were diagnosed, managed and monitored according to a standard protocol. Findings: Children between 10-15 years were most commonly afflicted (59%. Infants were the least affected sub-group (3.7%. Ninety two percent of all children were of DHF and 8% cases presented in DSS. The common symptoms seen were fever (91%, vomiting (41%, poor intake (21%, abdominal pain (16% and significant bleeding (15%. Hepatomegaly was present in 60% of cases. 85% of cases had petechiae alone, 15% had evidence of significant bleeding manifestation. Gastrointestinal bleeding was the commonest observed bleeding. The complications seen were liver dysfunction (14.8%, coagulopathy (3.7%, renal dysfunction (3.7%, and acute respiratory distress syndrome (2.4% and disseminated intravascular coagulation (1.2%. Mortality in the study was 3.7%. Refractory shock and coagulopathy were seen in all cases with poor outcome. Conclusion: Increased awareness, better transport facilities and case management according to the WHO guidelines, is needed to further reduce mortality of DHF/DSS cases.

  5. WEB Services Implementation on The Report of Dengue Hemorrhagic Fever (DHF At Health Office Karanganyar

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    Ragil Saputra

    2013-06-01