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Sample records for dengue fever vector

  1. Dengue fever

    African Journals Online (AJOL)

    symptoms and research has been limited to studies ... severity and problems with vaccination (4). History of ... Americas in 1970s reduced the spread of dengue fever. After this .... Reiter P. Yellow fever and dengue: a threat to Europe? 9.

  2. PREDICTION OF DENGUE FEVER EPIDEMIC SPREADING USING DYNAMICS TRANSMISSION VECTOR MODEL

    Directory of Open Access Journals (Sweden)

    Retno Widyaningrum

    2014-05-01

    Full Text Available Increasing number of dengue cases in Surabaya shows that its city has high potential of dengue fever epidemic. Although some policies were designed by Surabaya Health Department, such as fogging and mosquito’s nest eradication, but these efforts still out of target because of inaccurate predictions. Ineffectiveness eradication of dengue fever epidemic is caused by lack of information and knowledge on environmental conditions in Surabaya. Developing spread and prediction system to minimize dengue fever epidemic is necessary to be conducted immediately. Spread and prediction system can improve eradication and prevention accuracy. The transmission dynamics vector simulation will be used as an approach to draw a complex system ofmosquito life cycle in which involve a lot offactors. Dynamics transmission model used to build model in mosquito model (oviposition rate and pre adult mosquito, infected and death cases in dengue fever. The model of mosquito and infected population can represent system. The output of this research is website of spread and prediction system of dengue fever epidemics to predict growth rate of Aedes Aegypti mosquito, infected, and death population because of dengue fever epidemics. The deviation of infected population is 0,519. The model of death cases in dengue fever is less precision with the deviation 1,229. Death cases model need improvement by adding some variables that influence to dengue fever death cases. Spread ofdengue fever prediction will help the government, health department to decide the best policies in minimizing the spread ofdengue fever 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. Evaluation of Pyrethrin Formulations on Dengue/Dengue Haemorrhagic Fever Vectors in the Laboratory and Sublethal Effects

    Directory of Open Access Journals (Sweden)

    S Sulaiman

    2007-11-01

    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.

  5. 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.

  6. Psychosis in dengue fever

    OpenAIRE

    Suprakash Chaudhury; Biswajit Jagtap; Deepak Kumar Ghosh

    2017-01-01

    An 18-year-old male student developed abnormal behavior while undergoing treatment for dengue fever. He was ill-kempt, irritable and had auditory and visual hallucinations and vague persecutory delusions in clear sensorium with impaired insight. The psychotic episode had a temporal correlation with dengue fever. Psychiatric comorbidities of dengue fever including mania, anxiety, depression, and catatonia are mentioned in literature but the literature on the psychosis following dengue is spars...

  7. 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

  8. 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.

  9. Tri-phasic fever in dengue fever.

    Science.gov (United States)

    D, Pradeepa H; Rao, Sathish B; B, Ganaraj; Bhat, Gopalakrishna; M, Chakrapani

    2018-04-01

    Dengue fever is an acute febrile illness with a duration of 2-12 days. Our observational study observed the 24-h continuous tympanic temperature pattern of 15 patients with dengue fever and compared this with 26 others with fever due to a non-dengue aetiology. A tri-phasic fever pattern was seen among two-thirds of dengue fever patients, but in only one with an inflammatory disease. One-third of dengue fever patients exhibited a single peak temperature. Continuous temperature monitoring and temperature pattern analysis in clinical settings can aid in the early differentiation of dengue fever from non-dengue aetiology.

  10. A survey of bacterial, fungal and plant metabolites against Aedes aegypti (Diptera: Culicidae), the vector of yellow and dengue fevers and Zika virus

    Science.gov (United States)

    Aedes aegypti L. is the major vector of the arboviruses responsible for dengue fever, one of the most devastating human diseases. Some bacterial, fungal and plant metabolites including Amaryllidaceae alkaloids belonging to different chemical subgroups, including anthracenes, azoxymethoxytetrahydropy...

  11. RELATIONSHIP BETWEEN KNOWLEDGE OF VECTOR WITH HOUSEHOLD INSECTICIDE USAGE BEHAVIOR IN DENGUE HEMORRHAGIC FEVER ENDEMIC AREAS IN BALI PROVINCE

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    Diana Andriyani Pratamawati

    2014-06-01

    Full Text Available Bali Province has a case fatality rate (CFR of Dengue Hemorrhagic Fever (DHF 56.16 per100,000 populations in 2011. Data of Riskesdas 2010 showed that anti mosquito (householdinsecticides was the most widely used by people to prevent vector borne diseases. This studyaimed to describe behavior by using household insecticides to prevent DHF and determinewhether this behavior was based on dengue vector knowledge. This research was a descriptivestudy using survey methods. Unit analysis was households in DHF endemic area in DenpasarCity, Gianyar and Badung Regency which had highest dengue cases until August 2011. Resultsshowed that 54.5% of the 88 respondents has high level in dengue vector knowledge. Mostrespondents (59.1% has good category in household insecticide usage behavior. Kendall taucorrelation test (t showed no significant relation between knowledge of dengue vectors withhousehold insecticide usage behavior for dengue vector control (t = 0,076, p value= 0,479.Keywords: Knowledge, Vector, Dengue Hemorrhagic Fever, HouseholdInsecticides Provinsi Bali memiliki case fatality rate (CFR Demam Berdarah Dengue (DBD 56,16 per100.000 penduduk pada tahun 2011. Data Riskesdas 2010 menunjukkan bahwa obat antinyamuk (insektisida rumah tangga merupakan cara yang paling banyak digunakan olehmasyarakat untuk mencegah penyakit tular vektor. Studi ini bertujuan untuk mendeskripsikanperilaku dalam menggunakan insektisida rumah tangga untuk mencegah DBDserta mengetahuiapakah perilaku ini didasari oleh pengetahuanmengenai vektor DBD. Penelitian ini merupakanstudi deskriptif dengan menggunakan metode survei. Unit analisis adalah rumah tangga didaerah endemis DBD di Kota Denpasar, Kabupaten Gianyar, dan Kabupaten Badung yangmemiliki kasus DBD tertinggi hingga bulan Agustus tahun 2011. Hasil penelitianmenunjukkan bahwa 54,5% dari 88 responden memiliki tingkat pengetahuan yang tinggitentang vektor DBD. Sebagian besar responden (59,1% memiliki perilaku

  12. Dengue fever: a Wikipedia clinical review.

    Science.gov (United States)

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

    2014-01-01

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

  13. Treatment of dengue fever

    OpenAIRE

    Rajapakse, Senaka; Rodrigo,Chaturaka; Rajapakse,Anoja Chamarie

    2012-01-01

    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 decad...

  14. 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.

  15. Rotenoids from Tephrosia toxicaria with larvicidal activity against Aedes aegypti, the main vector of dengue fever

    International Nuclear Information System (INIS)

    Vasconcelos, Jackson Nunes e; Santiago, Gilvandete Maria Pinheiro; Lima, Jefferson Queiroz; Arriaga, Angela Martha Campos

    2012-01-01

    In the search for new larvicides from plants, we have investigated the potential activity of the rotenoids deguelin (1), 12a-hydroxy-a-toxicarol (2) and tephrosin (3), isolated from the bioactive ethanol extract of roots of Tephrosia toxicaria Pers., against Aedes aegypti, the main vector of dengue. The absolute configuration of these compounds was determined by circular dichroism (CD) spectra. The LC50 values of the compounds evaluated justify the potential of T. toxicaria as a new natural larvicide. (author)

  16. Transmission Dinamics Model Of Dengue Fever

    Science.gov (United States)

    Debora; Rendy; Rahmi

    2018-01-01

    Dengue fever is an endemic disease that is transmitted through the Aedes aegypti mosquito vector. The disease is present in more than 100 countries in America, Africa, and Asia, especially tropical countries. Differential equations can be used to represent the spread of dengue virus occurring in time intervals and model in the form of mathematical models. The mathematical model in this study tries to represent the spread of dengue fever based on the data obtained and the assumptions used. The mathematical model used is a mathematical model consisting of Susceptible (S), Infected (I), Viruses (V) subpopulations. The SIV mathematical model is then analyzed to see the solution behaviour of the system.

  17. A survey of bacterial, fungal and plant metabolites against Aedes aegypti (Diptera: Culicidae), the vector of yellow and dengue fevers and Zika virus

    OpenAIRE

    Masi Marco; Cimmino Alessio; Tabanca Nurhayat; Becnel James J.; Bloomquist Jeffrey R.; Evidente Antonio

    2017-01-01

    Aedes aegypti L. is the major vector of the arboviruses responsible for dengue fever, one of the most devastating human diseases. Some bacterial, fungal and plant metabolites belonging to different chemical subgroups, including Amaryllidaceae alkaloids, anthracenes, azoxymethoxytetrahydropyrans, cytochalasans, 2,5-diketopiperazines, isochromanones, naphthoquinones, organic small acids and their methyl esters, sterols and terpenes including sesquiterpenes and diterpenes, were tested for their ...

  18. VECTOR RESISTANCE STATUS OF DENGUE HEMORRHAGIC FEVER (Aedes aegypti IN THE SIDOREJO DISTRICT SALATIGA CITY AGAINST TEMEPHOS (ORGANOPHOSPHATES

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    Ary Oktsari Yanti S

    2014-06-01

    Full Text Available One of the efforts to control the incidence of Dengue Hemorrhagic Fever (DHF is contrled thedengue vector larvae using larvasida. The most widely larvasida used to control larvae Ae.aegypti is temephos. In Indonesia 1% temephos (abate 1SG has been used since 1976, and since1980 has been used for the eradication program ofAe. aegypti larvae. The purpose of this studyis to determine the resistance status of vectors of dengue hemorrhagic fever (Ae. aegypti ofendemic, sporadic, and potentially in Sub District Sidorejo Salatiga City to temephos(organofosfat. This research was conducted using experimental research design (TrueExperiment, posttcst design with control groups (posttest-only Control Group Design. Thepopulation of the research were larvae of Ae. aegypti collected from the study area. Samples testlarvae were used of Ae. aegypti third and early fourth instars larvae which were maintenance ofthe first generation. The result showed that the mortality percentages of Ae. aegypti larvaeof endemic, sporadic and potential administratives against temephos using WHO standardconcentration (0,625; 0,125; 0,025 mg/1 indicates the mortality of Ae. aegypti larvae by 100%Based on the status resistance criteria, Ae. aegypti larvae from endemic, sporadic, and potentialadministratives of Sidorejo Sub-District, Salatiga City is still susceptible to temephos.Keywords : Status of resistance, Aedes aegypti. TemephosSalah satu upaya menurunkan Demam Berdarah Dengue (DBD adalah melaluipengcndalian jentik vektor DBD dengan larvasida. Larvasida yang digunakan untukmengcndalikan jentik Ae. aegypti adalah temephos. Temephos 1% (abate ISG sudah programdi Indonesia sejak 1976, scjak 1980 telah digunakan secara massal untuk programpemberantasan jentik Ae. aegypti. Tujuan penelitian ini adalah untuk mengetahui status resistensivektor demam berdarah dengue Ae. aegypti di kclurahan endemis, sporadis, dan potensialKecamatan Sidorejo Kota Salatiga terhadap temephos

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

    Science.gov (United States)

    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.

  20. Strain Variation in the Transcriptome of the Dengue Fever Vector, Aedes aegypti.

    Science.gov (United States)

    Bonizzoni, Mariangela; Dunn, W Augustine; Campbell, Corey L; Olson, Ken E; Marinotti, Osvaldo; James, Anthony A

    2012-01-01

    Studies of transcriptome dynamics provide a basis for understanding functional elements of the genome and the complexity of gene regulation. The dengue vector mosquito, Aedes aegypti, exhibits great adaptability to diverse ecological conditions, is phenotypically polymorphic, and shows variation in vectorial capacity to arboviruses. Previous genome sequencing showed richness in repetitive DNA and transposable elements that can contribute to genome plasticity. Population genetic studies revealed a varying degree of worldwide genetic polymorphism. However, the extent of functional genetic polymorphism across strains is unknown. The transcriptomes of three Ae. aegypti strains, Chetumal (CTM), Rexville D-Puerto Rico (Rex-D) and Liverpool (LVP), were compared. CTM is more susceptible than Rex- D to infection by dengue virus serotype 2. A total of 4188 transcripts exhibit either no or small variation (<2-fold) among sugar-fed samples of the three strains and between sugar- and blood-fed samples within each strain, corresponding most likely to genes encoding products necessary for vital functions. Transcripts enriched in blood-fed mosquitoes encode proteins associated with catalytic activities, molecular transport, metabolism of lipids, carbohydrates and amino acids, and functions related to blood digestion and the progression of the gonotropic cycle. Significant qualitative and quantitative differences were found in individual transcripts among strains including differential representation of paralogous gene products. The majority of immunity-associated transcripts decreased in accumulation after a bloodmeal and the results are discussed in relation to the different susceptibility of CTM and Rex-D mosquitoes to DENV2 infection.

  1. 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. © The American Society of Tropical Medicine and Hygiene.

  2. Dengue fever: diagnosis and treatment.

    Science.gov (United States)

    Wiwanitkit, Viroj

    2010-07-01

    Dengue fever is a common tropical infection. This acute febrile illness can be a deadly infection in cases of severe manifestation, causing dengue hemorrhagic shock. In this brief article, I will summarize and discuss the diagnosis and treatment of this disease. For diagnosis of dengue, most tropical doctors make use of presumptive diagnosis; however, the definite diagnosis should be based on immunodiagnosis or viral study. Focusing on treatment, symptomatic and supportive treatment is the main therapeutic approach. The role of antiviral drugs in the treatment of dengue fever has been limited, but is currently widely studied.

  3. Potential Risk Areas of Aedes albopictus in South-Eastern Iran: A Vector of Dengue Fever, Zika, and Chikungunya

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    Jalil Nejati

    2017-09-01

    Full Text Available The possibility of the rapid and global spread of Zika, chikungunya, yellow fever, and dengue fever by Aedes albopictus is well documented and may be facilitated by changes in climate. To avert and manage health risks, climatic and topographic information can be used to model and forecast which areas may be most prone to the establishment of Ae. albopictus. We aimed to weigh and prioritize the predictive value of various meteorological and climatic variables on distributions of Ae. albopictus in south-eastern Iran using the Analytical Hierarchy Process. Out of eight factors used to predict the presence of Ae. albopictus, the highest weighted were land use, followed by temperature, altitude, and precipitation. The inconsistency of this analysis was 0.03 with no missing judgments. The areas predicted to be most at risk of Ae. albopictus-borne diseases were mapped using Geographic Information Systems and remote sensing data. Five-year (2011–2015 meteorological data was collected from 11 meteorological stations and other data was acquired from Landsat and Terra satellite images. Southernmost regions were at greatest risk of Ae. albopictus colonization as well as more urban sites connected by provincial roads. This is the first study in Iran to determine the regional probability of Ae. albopictus establishment. Monitoring and collection of Ae. albopictus from the environment confirmed our projections, though on-going field work is necessary to track the spread of this vector of life-threatening disease.

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

    OpenAIRE

    Tantawichien, Terapong

    2012-01-01

    Dengue fever (DF) is endemic in tropical and subtropical zones and the prevalence is increasing across South-east Asia, Africa, the Western Pacific and the Americas. In recent years, the spread of unplanned urbanisation, with associated substandard housing, overcrowding and deterioration in water, sewage and waste management systems, has created ideal conditions for increased transmission of the dengue virus in tropical urban centres. While dengue infection has traditionally been considered a...

  5. THROMBOCYTOPENIA IN DENGUE HAEMORRHAGIC FEVER

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    I Wayan Putu Sutirta-Yasa

    2013-04-01

    Full Text Available The incidence and geographical distribution of dengue has gradually increased during the past decade. Today, dengue is considered one of the most important arthropod-borne viral diseasases in humans in term of morbidity and mortality. Dengue infection   a potential life-threatening dengue hemorrhagic fever (DHF / dengue shock syndrome(DSS, characterized by thrombocytopenia and increased vascular permiability. Thrombocytopenia causes bleeding, but in   DHF patients with thrombocytopenia do not always develop bleeding manifestation. The pathogenesis of thrombocytopenia are not cleared. Multiple factors  may be involved in the machanisms leading to thrombocytopenia in DHF/DSS patients.

  6. Aedes albopictus (Skuse, 1894) infected with the American-Asian genotype of dengue type 2 virus in Medellín suggests its possible role as vector of dengue fever in Colombia.

    Science.gov (United States)

    Gómez-Palacio, Andrés; Suaza-Vasco, Juan; Castaño, Sandra; Triana, Omar; Uribe, Sandra

    2017-03-29

    Aedes aegypti and Ae. albopictus are recognized vectors of dengue, yellow fever, chikungunya and Zika arboviruses in several countries worldwide. In Colombia, Ae. albopictus geographical distribution has increased to include highly populated cities such as Cali and Medellín. Although this species has been frequently found in urban and semi-urban zones in the country, its role as vector of the dengue fever is poorly known. To identify the presence of Ae. albopictus specimens naturally infected with dengue virus collected in Medellín. Insects were collected in the Universidad Nacional de Colombia campus in Medellín. Individuals were classified as Ae. albopictus and confirmed by DNA barcode region analysis. Mosquitoes were processed for dengue virus identification, and a fragment of the NS3 gen was sequenced and compared with DENV-2 genotypes reported in the literature. Sequence analysis of COI indicated Ae. albopictus individuals were similar to those recently reported in Colombia, and genetically close to those from other regions worldwide. Among the pools tested one was positive for DENV-2, and the NS3 analysis indicated it belonged to the Asian-American clade. We report the presence Ae. albopictus naturally infected with the Asian-American genotype of DENV-2 in Colombia. The presence of Ae. albopictus specimens carrying the most common genotype infecting humans in a highly populated city such as Medellín indicates its potential role as dengue vector in Colombia and highlights the relevance of including it in current vector surveillance strategies.

  7. RNA Interference: A Promising Tool in the Control of Important Vector Born Diseases Zika, Dengue Fever, and Malaria

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    Jalil Nejati

    2017-05-01

    Full Text Available Background and Objectives: RNA interference is a process, in which a molecule of double-stranded RNA prevents the expression of a particular gene and leads to its silencing. Application of this technology in the control of disease-carrying insects is rising in agriculture and medical sciences. Also, its application in control of insect-borne diseases could be considered as a new, important, and effective approach. In this article, it was attempted to study the mechanisms of RNA interference, routs of its delivery to insects, as well as its application in genetic control of disease vector insects. Methods: In this study, 71 indexed articles in databases, such as Pubmed, SID, Scopus, Science direct, and Google scholar, were used. Results: dsRNA could be delivered to insect body through three routes of oral, injection, and Impregnation. The mechanism of dsRNA entrance into the cells has considerable effect on the success and applicability of this technique. Identification of host-parasite relationship in the insect body is one of the important applications of RNAi in medical entomology. Conclusion: Although, there is a considerable number of researches on RNAi in the agricultural pests field, studies on insect vectors of human diseases have been mostly in-vivo. However, application of RNAi is suggested as a new, safe and applicable approach, alone or along with other methods. Certainly, further researches in this field can pave the way for enforcement measures in the control of disease vectors, especially Zika, dengue fever, and malaria in the not so distant future.

  8. 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...

  9. Dengue fever: a Wikipedia clinical review

    OpenAIRE

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

    2014-01-01

    Dengue fever, also known as breakbone fever, is a mosquito-borne infectious tropical disease caused by the dengue virus. Symptoms include fever, headache, muscle and joint pains, and a characteristic skin rash that is similar to measles. In a small proportion of cases, the disease develops into life-threatening dengue hemorrhagic fever, which results in bleeding, thrombocytopenia, and leakage of blood plasma, or into dengue shock syndrome, in which dangerously low blood pressure occurs. Treat...

  10. 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.

  11. 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.

  12. 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.

  13. Dengue fever outbreak: a clinical management experience

    International Nuclear Information System (INIS)

    Ahmed, S.; Illyas, M.

    2008-01-01

    To determine the frequency of dengue as a cause of fever and compare the clinical and haematological characteristics of Dengue-probable and Dengue-proven cases. All patients with age above 14 years, who were either hospitalized or treated in medical outdoor clinic due to acute febrile illness, were evaluated for clinical features of Dengue Fever (DF), Dengue haemorrhagic fever (DHF) and Dengue Shock Syndrome (DSS). Patients showing typical clinical features and haematological findings suggestive of Dengue fever (As per WHO criteria) were evaluated in detail for comparison of probable and confirmed cases of Dengue fever. All other cases of acute febrile illness, not showing clinical features or haematological abnormalities of Dengue fever, were excluded. The clinical and laboratory features were recorded on SPSS 11.0 programme and graded where required, for descriptive and statistical analysis. Out of 5200 patients with febrile illness, 107 (2%) presented with typical features of DF, 40/107 (37%) were Dengue-proven while 67/107 (63%) were Dengue-probable. Out of Dengue-proven cases, 38 were of DF and 2 were of DHF. Day 1 temperature ranged from 99-105 degreeC (mean 101 degree C). Chills and rigors were noticed in 86 (80%), myalgia in 67%, headache in 54%, pharyngitis in 35%, rash in 28%, and bleeding manifestations in 2% cases. Hepatomegaly in 1(0.5%), lymphadenopathy in 1 (0.5%) and splenomegaly in 12 (11.2%) cases. Leucopoenia (count 40 U/L in 57% cases. Frequency of clinically suspected dengue virus infection was 107 (2%), while confirmed dengue fever cases were 40 (0.8%) out of 5200 fever cases. Fever with chills and rigors, body aches, headache, myalgia, rash, haemorrhagic manifestations, platelet count, total leukocyte count, and ALT, are parameters to screen the cases of suspected dengue virus infection, the diagnosis cannot be confirmed unless supported by molecular studies or dengue specific IgM. (author)

  14. 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.

  15. Dengue Fever Treatment

    Science.gov (United States)

    ... AIDS Influenza Malaria Respiratory Syncytial Virus (RSV) Tuberculosis Zika Virus Find a Funding Opportunity Opportunities & Announcements Types of ... For example, the entire genome sequence of the Aedes aegypti mosquito, the main carrier of dengue virus, has been decoded and is available to qualified ...

  16. A model of dengue fever

    Directory of Open Access Journals (Sweden)

    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.

  17. CLINICAL AND LABORATORY PROFILE OF DENGUE FEVER

    Directory of Open Access Journals (Sweden)

    Farhan Fazal

    2015-02-01

    Full Text Available AIM: Dengue is a major health problem in many parts of India and Gulbarga (North Karnataka was previously not a known endemic area f or dengue. Infection with dengue virus can cause a spectrum of three clinical syndromes , classic dengue fever (DF , dengue hemorrhagic fever (DHF and dengue shock syndrome (DSS. The present study was undertaken to determine the disease profile of dengue virus infection in hospitalized patients. METHODS AND MATERIAL: One hundred patients admitted in Basaveshwar Teaching and General hospital with fever more than 38.5 degree Celsius and IgM dengue positive were selected. They were followed from the onset of fever to twelve days or till they are recovered according to WHO discharge criteria whichever is earlier. They underwent relevant investigations to identify specific organ dysfunction and categorize them into the spectrum of Dengue fever in accordance to W HO criteria . RESULTS: Out of 100 cases in this study 70 cases belongs to DF , 23 cases to DHF and 7 cases to DSS based on WHO criteria. All the cases had fever (100%. Other common symptoms noted were myalgia (61% , joint pain (54% , headache (66% , vomitin g (55% , pain abdomen (48% , rash (41% , hepatomegaly (20% , bleeding (21% and shock (8%. Hess test was positive in 24% patients. Low platelet count of less than 100 , 000/cu mm according to WHO criteria was present in 73% patients. Deranged liver functio n test and renal parameters were seen in 26 and 8 patients respectively . Mortality documented was 7 patients due to delayed presentation. The average duration of hospital stay was 4.65 days. CONCLUSION: Dengue fever was a more common manifestation than DHF or DSS. During aepidemic , dengue should be strongly considered on the differential diagnosis of any patient with fever. The treatment of dengue is mainly fluid management and supportive. Early recognition and management of alarm symptoms is the key to bet ter outcome

  18. 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.

  19. Blood banking e Dengue fever

    OpenAIRE

    Ramos, Estácio F.

    2008-01-01

    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,...

  20. Hemophagocytic syndrome in classic dengue fever

    Directory of Open Access Journals (Sweden)

    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.

  1. Dengue fever outbreak: a clinical management experience.

    Science.gov (United States)

    Ahmed, Shahid; Ali, Nadir; Ashraf, Shahzad; Ilyas, Mohammad; Tariq, Waheed-Uz-Zaman; Chotani, Rashid A

    2008-01-01

    To determine the frequency of dengue as a cause of fever and compare the clinical and haematological characteristics of Dengue-probable and Dengue-proven cases. An observational study. The Combined Military Hospital, Malir Cantt., Karachi, from August 2005 to December 2006. All patients with age above 14 years, who were either hospitalized or treated in medical outdoor clinic due to acute febrile illness, were evaluated for clinical features of Dengue Fever (DF), Dengue haemorrhagic fever (DHF) and Dengue Shock Syndrome (DSS). Patients showing typical clinical features and haematological findings suggestive of Dengue fever (As per WHO criteria) were evaluated in detail for comparison of probable and confirmed cases of Dengue fever. All other cases of acute febrile illness, not showing clinical features or haematological abnormalities of Dengue fever, were excluded. The clinical and laboratory features were recorded on SPSS 11.0 programme and graded where required, for descriptive and statistical analysis. Out of 5200 patients with febrile illness, 107(2%) presented with typical features of DF, 40/107(37%) were Dengue-proven while 67/107(63%) were Dengue-probable. Out of Dengue-proven cases, 38 were of DF and 2 were of DHF. Day 1 temperature ranged from 99-1050C (mean 1010C). Chills and rigors were noticed in 86 (80%), myalgia in 67%, headache in 54%, pharyngitis in 35%, rash in 28%, and bleeding manifestations in 2% cases. Hepatomegaly in 1(0.5%), lymphadenopathy in 1(0.5%) and splenomegaly in 12 (11.2%) cases. Leucopoenia (count40 U/L in 57% cases. Frequency of clinically suspected dengue virus infection was 107 (2%), while confirmed dengue fever cases were 40 (0.8%) out of 5200 fever cases. Fever with chills and rigors, body aches, headache, myalgia, rash, haemorrhagic manifestations, platelet count, total leukocyte count, and ALT, are parameters to screen the cases of suspected dengue virus infection; the diagnosis cannot be confirmed unless supported by

  2. 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, ...

  3. 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

  4. Dengue Fever in the United States

    Centers for Disease Control (CDC) Podcasts

    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.

  5. Acute atrial fibrillation during dengue hemorrhagic fever

    Directory of Open Access Journals (Sweden)

    Henrique Horta Veloso

    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.

  6. Acute atrial fibrillation during dengue hemorrhagic fever

    Directory of Open Access Journals (Sweden)

    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.

  7. 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.

  8. Angelica sinensis (Umbelliferae) with proven repellent properties against Aedes aegypti, the primary dengue fever vector in Thailand.

    Science.gov (United States)

    Champakaew, D; Junkum, A; Chaithong, U; Jitpakdi, A; Riyong, D; Sanghong, R; Intirach, J; Muangmoon, R; Chansang, A; Tuetun, B; Pitasawat, B

    2015-06-01

    Botanical resources with great diversity in medicinal and aromatic plants are a rich and reliable source for finding insect repellents of plant origin, which are widely popular among today's consumers. Although some herbal-based repellents have been proven comparable to or even better than synthetics, commercially available natural repellents generally tend to be expensive, with short-lived effectiveness. This critical flaw leads to ongoing research for new and effective repellents, which provide longer protection against vector and nuisance-biting insects, while remaining safe, user friendly, and reasonably priced. This study aimed to evaluate the repellent activity of plant-derived products against the primary dengue vector, Aedes aegypti, by following the human bait technique of World Health Organization guidelines. Preliminary laboratory screening tests for repellency of 33 plant species clearly demonstrated Angelica sinensis as the most effective repellent from each kind of extracted product, with its essential oil and ethanolic extract having median complete protection times of 7.0 h (6.0-7.5) and 2.5 h (2.0-2.5), respectively. Due to its low yield (0.02 %), pungent smell, and little cause of irritation, A. sinensis essential oil did not qualify as a candidate for further repellent assessment. However, subsequent extractions of A. sinensis with different organic solvents of increasing polarity provided four extractants with varying degrees of repellency against A. aegypti. The hexane extract of A. sinensis provided excellent repellency, with a median complete protection time of 7.5 h (6.5-8.5), which was longer than that of ethanol (2.5, 2.0-2.5 h), acetone (1.75, 0.5-2.5 h), and methanol extracts (0.5, 0-1.0 h). By being the most effective product, A. sinensis hexane extract gave significant protection comparable to that of its essential oil and the standard synthetic repellent, N,N-diethyl-3-methylbenzamide (DEET: 6.25, 5.0-6.5 h). Qualitative gas

  9. Dengue Haemorrhagic Fever presenting as Acute Abdomen

    OpenAIRE

    Al-Araimi, Hanaa; Al-Jabri, Amal; Mehmoud, Arshad; Al-Abri, Seif

    2011-01-01

    We describe a case of a 38 year-old Sri Lankan female who was referred to the surgeon on call with a picture of acute abdomen. She presented with a three-day history of fever, headache, abdominal pain and diarrhoea; however, the physical examination was not consistent with acute abdomen. Her platelet count was 22 ×109/L. A diagnosis of dengue haemorrhagic fever (DHF) was made and dengue serology was positive. Dengue epidemics have been associated with a variety of gastrointestinal symptoms an...

  10. Dengue and dengue haemorrhagic fever: Indian perspective

    Indian Academy of Sciences (India)

    PRAKASH KUMAR

    mainly in children (Halstead 2002, 2007; Chaturvedi and. Shrivastava 2004). Dengue ... of molecular epidemiology, immunopathology and vaccine development. Selected work done in ..... Only the Indian initiative in this field is presented here.

  11. Dengue Fever: Causes, Complications, and Vaccine Strategies

    Directory of Open Access Journals (Sweden)

    Niyati Khetarpal

    2016-01-01

    Full Text Available Dengue is a highly endemic infectious disease of the tropical countries and is rapidly becoming a global burden. It is caused by any of the 4 serotypes of dengue virus and is transmitted within humans through female Aedes mosquitoes. Dengue disease varies from mild fever to severe conditions of dengue hemorrhagic fever and shock syndrome. Globalization, increased air travel, and unplanned urbanization have led to increase in the rate of infection and helped dengue to expand its geographic and demographic distribution. Dengue vaccine development has been a challenging task due to the existence of four antigenically distinct dengue virus serotypes, each capable of eliciting cross-reactive and disease-enhancing antibody response against the remaining three serotypes. Recently, Sanofi Pasteur’s chimeric live-attenuated dengue vaccine candidate has been approved in Mexico, Brazil, and Philippines for usage in adults between 9 and 45 years of age. The impact of its limited application to the public health system needs to be evaluated. Simultaneously, the restricted application of this vaccine candidate warrants continued efforts in developing a dengue vaccine candidate which is additionally efficacious for infants and naïve individuals. In this context, alternative strategies of developing a designed vaccine candidate which does not allow production of enhancing antibodies should be explored, as it may expand the umbrella of efficacy to include infants and naïve individuals.

  12. A survey of bacterial, fungal and plant metabolites against Aedes aegypti (Diptera: Culicidae, the vector of yellow and dengue fevers and Zika virus

    Directory of Open Access Journals (Sweden)

    Masi Marco

    2017-06-01

    Full Text Available Aedes aegypti L. is the major vector of the arboviruses responsible for dengue fever, one of the most devastating human diseases. Some bacterial, fungal and plant metabolites belonging to different chemical subgroups, including Amaryllidaceae alkaloids, anthracenes, azoxymethoxytetrahydropyrans, cytochalasans, 2,5-diketopiperazines, isochromanones, naphthoquinones, organic small acids and their methyl esters, sterols and terpenes including sesquiterpenes and diterpenes, were tested for their larvicidal and adulticidal activity against Ae. aegypti. Out of 23 compounds tested, gliotoxin exhibited mosquitocidal activity in both bioassays with an LC50 value of 0.0257 ± 0.001 µg/µL against 1st instar Ae. aegypti and LD50 value of 2.79 ± 0.1197 µg/mosquito against adult female Ae. aegypti. 2-Methoxy-1,4-naphthoquinone and cytochalasin A showed LC50 values of 0.0851 ± 0.0012 µg/µL and 0.0854 ± 0.0019 µg/µL, respectively, against Ae. aegypti larvae. In adult bioassays, fusaric acid (LD50= 0.8349 ± 0.0118 µg/mosquito, 3-nitropropionic acid (LD50 = 1.6641 ± 0.0494 µg/mosquito and α-costic acid (LD50 = 2.547 ± 0.0835 µg/mosquito exhibited adulticidal activity. Results from the current study confirm that compounds belonging to cytochalsin, diketopiperazine, naphthoquinone and low molecular weight organic acid groups are active and may stimulate further SAR investigations.

  13. Physiological and Histological Alterations in Rats Liver Induced by Sumithion NP 25/2.5 EC, an Insecticide Used in Dengue Fever Vector Control in Jeddah, Saudi Arabia

    International Nuclear Information System (INIS)

    AlJahdali, Mohammed O.; Bisher, Ameen S. Bin; Zeid, Isam M. Abu

    2009-01-01

    The hepatotoxicity of Sumithion NP 25/2.5 EC, a new formulated organophosphorous insecticide used in dengue fever vector (Aedes aegypti) control in Jeddah (Saudi Arabia), was studied in albino rats. Both levels of GPT, GOT and ALP, and the combined histological alterations were assessed after treatment. Rats were daily injected intraperitoneally for two and four weeks with 80 and 200 mg/kg of body weight (1/10 and 1/4 of the LD50, respectively). Significant increase in GPT, GOT and ALP levels relative to the increase of treatment dose and duration time was observed. The time factor effect was remarkably noticed in ALP level fluctuation. These results indicate a remarkable defect in the liver functions induced by Sumithion NP 25/2.5 EC. Also, histological alterations in the treated animal's liver were observed including: blood congestion, fatty degeneration, hepatocytes swelling and necrosis. The liver syndrome's intensity correlated with the increase in dose and duration time. The present results could prove the hepatotoxicity of Sumithion NP 25/2.5 EC and its ability to cause severe physiological and histopathological defects in the liver. Therefore, the chemical control of Aedes aegypti must be reduced and other recommended control strategies should be promoted. (author)

  14. 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.

  15. Cost of Dengue Vector Control Activities in Malaysia

    Science.gov (United States)

    Packierisamy, P. Raviwharmman; Ng, Chiu-Wan; Dahlui, Maznah; Inbaraj, Jonathan; Balan, Venugopalan K.; Halasa, Yara A.; Shepard, Donald S.

    2015-01-01

    Dengue fever, an arbovirus disease transmitted by Aedes mosquitoes, has recently spread rapidly, especially in the tropical countries of the Americas and Asia-Pacific regions. It is endemic in Malaysia, with an annual average of 37,937 reported dengue cases from 2007 to 2012. This study measured the overall economic impact of dengue in Malaysia, and estimated the costs of dengue prevention. In 2010, Malaysia spent US$73.5 million or 0.03% of the country's GDP on its National Dengue Vector Control Program. This spending represented US$1,591 per reported dengue case and US$2.68 per capita population. Most (92.2%) of this spending occurred in districts, primarily for fogging. A previous paper estimated the annual cost of dengue illness in the country at US$102.2 million. Thus, the inclusion of preventive activities increases the substantial estimated cost of dengue to US$175.7 million, or 72% above illness costs alone. If innovative technologies for dengue vector control prove efficacious, and a dengue vaccine was introduced, substantial existing spending could be rechanneled to fund them. PMID:26416116

  16. Cost of Dengue Vector Control Activities in Malaysia.

    Science.gov (United States)

    Packierisamy, P Raviwharmman; Ng, Chiu-Wan; Dahlui, Maznah; Inbaraj, Jonathan; Balan, Venugopalan K; Halasa, Yara A; Shepard, Donald S

    2015-11-01

    Dengue fever, an arbovirus disease transmitted by Aedes mosquitoes, has recently spread rapidly, especially in the tropical countries of the Americas and Asia-Pacific regions. It is endemic in Malaysia, with an annual average of 37,937 reported dengue cases from 2007 to 2012. This study measured the overall economic impact of dengue in Malaysia, and estimated the costs of dengue prevention. In 2010, Malaysia spent US$73.5 million or 0.03% of the country's GDP on its National Dengue Vector Control Program. This spending represented US$1,591 per reported dengue case and US$2.68 per capita population. Most (92.2%) of this spending occurred in districts, primarily for fogging. A previous paper estimated the annual cost of dengue illness in the country at US$102.2 million. Thus, the inclusion of preventive activities increases the substantial estimated cost of dengue to US$175.7 million, or 72% above illness costs alone. If innovative technologies for dengue vector control prove efficacious, and a dengue vaccine was introduced, substantial existing spending could be rechanneled to fund them. © The American Society of Tropical Medicine and Hygiene.

  17. Vitamin D serostatus and dengue fever progression to dengue hemorrhagic fever/dengue shock syndrome.

    Science.gov (United States)

    Villamor, E; Villar, L A; Lozano, A; Herrera, V M; Herrán, O F

    2017-10-01

    Vitamin D could modulate pathways leading to dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS). We examined the associations of serum total 25-hydroxy vitamin D [25(OH)D] and vitamin D binding protein (VDBP) concentrations in patients with uncomplicated dengue fever (DF) with risk of progression to DHF/DSS. In a case-control study nested in a cohort of DF patients who were followed during the acute episode in Bucaramanga, Colombia, we compared 25(OH)D and VDBP at onset of fever between 110 cases who progressed to DHF/DSS and 235 DF controls who did not progress. 25(OH)D concentrations were also compared between the acute sample and a sample collected >1 year post-convalescence in a subgroup. Compared with 25(OH)D ⩾75 nmol/l, adjusted odds ratios (95% CI) for progression were 0·44 (0·22-0·88) and 0·13 (0·02-1·05) for 50 to 75 nmol/l (vitamin D insufficiency) and <50 nmol/l (vitamin D deficiency), respectively (P, trend = 0·003). Mean 25(OH)D concentrations were much lower post-convalescence compared with the acute episode, regardless of case status. Compared with controls, mean VDBP was non-significantly lower in cases. We conclude that low serum 25(OH)D concentrations in DF patients predict decreased odds of progression to DHF/DSS.

  18. 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.

  19. Dengue and dengue hemorrhagic fever in the Americas: lessons and challenges.

    Science.gov (United States)

    Guzman, María G; Kouri, Gustavo

    2003-05-01

    The incidence of dengue and dengue hemorrhagic fever (DF/DHF) has increased significantly over the last decades. Yearly, an estimated 50-100 million cases of DF and about 250000-500000 cases of DHF occur worldwide. The epidemiological situation in Latin America now resembles that in Southeast Asia. Here, the main clinical, epidemiological and virological observations in the American region are presented and compared with those previously reported from Southeast Asia. During 2002, more than 30 Latin American countries reported over 1000000 DF cases. DHF occurred in 20 countries with more than 17000 DHF cases, including 225 fatalities. The co-circulation of multiple serotypes has been reported from many countries. In the Americas, DHF is observed both in children and adults; secondary infection by a different dengue virus serotype has been confirmed as an important risk factor for this severe form of the disease. However, some new risk factors such as the interval of dengue virus infections and the ethnicity and underlying chronic conditions of the patient have also been identified. The sequence of dengue virus infections and association with certain genotypes are further factors of importance. We also discuss the control and prevention strategies. In conclusion, without urgent action for the prevention and control of dengue/DHF and its vector, the current situation will worsen and, more dramatical, there is a risk of the urbanization of yellow fever.

  20. 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.

  1. Dengue fever | Tavodova | South Sudan Medical Journal

    African Journals Online (AJOL)

    South Sudan Medical Journal. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 5, No 1 (2012) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register. Dengue fever. Milada Tavodova. Abstract. No Abstract ...

  2. Dengue fever in pregnancy: a case report

    Directory of Open Access Journals (Sweden)

    Phupong Vorapong

    2001-12-01

    Full Text Available Abstract Background Dengue, a mosquito-borne flavivirus infection, is endemic in Southeast Asia. Currently, the incidence has been increasing among adults. Case presentation A 26-year-old Thai woman, G1P0 31 weeks pregnancy, presented with epigastric pain for 1 day. She also had a high-grade fever for 4 days. The physical examination, complete blood counts as well as serology confirmed dengue fever. The patient was under conservative treatment despite severe thrombocytopenia. She was well at the 3rd day of discharge and 1-week follow-up. The pregnancy continued until term without any complication and she delivered vaginally a healthy female baby. Conclusions More cases of dengue infection in pregnancy can be found due to the increasing incidence during adulthood. It should be suspected when a pregnant woman presents with symptoms and signs like in a non-pregnant. Conservative treatment should be conducted unless there are any complications.

  3. Spontaneous muscle hematomas in a patient with Dengue hemorrhagic fever

    Directory of Open Access Journals (Sweden)

    Jency Maria Koshy

    2014-01-01

    Full Text Available Dengue hemorrhagic fever (DHF and Dengue shock syndrome manifest in various forms, ranging from petechial skin hemorrhage to life threatening cerebral, pulmonary, gastrointestinal and genitourinary hemorrhages. However it is very rare to have muscle hematomas in DHF. We report a rare case of spontaneous Iliopsoas hematoma complicating Dengue hemorrhagic fever.

  4. Clinical profile and outcome of Dengue fever cases.

    Science.gov (United States)

    Ratageri, Vinod H; Shepur, T A; Wari, P K; Chavan, S C; Mujahid, I B; Yergolkar, P N

    2005-08-01

    Dengue fever is on rise globally. In India, Dengue epidemics are expanding geographically, even into the rural areas. Dengue can present with varied manifestations. The mortality rate has been brought down with high index of suspicion, strict monitoring and proper fluid resuscitation. Herewith, we are presenting clinical features and outcome of Dengue cases seen in and around Hubli (North Karnataka).

  5. 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.

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

    Science.gov (United States)

    Mourão, Maria Paula Gomes; Lacerda, Marcus Vinícius Guimarães de; Bastos, Michele de Souza; Albuquerque, Bernardino Cláudio de; Alecrim, Wilson Duarte

    2004-12-01

    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.

  7. 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 ...

  8. Host genetics and dengue fever.

    Science.gov (United States)

    Xavier-Carvalho, Caroline; Cardoso, Cynthia Chester; de Souza Kehdy, Fernanda; Pacheco, Antonio Guilherme; Moraes, Milton Ozório

    2017-12-01

    Dengue is a major worldwide problem in tropical and subtropical areas; it is caused by four different viral serotypes, and it can manifest as asymptomatic, mild, or severe. Many factors interact to determine the severity of the disease, including the genetic profile of the infected patient. However, the mechanisms that lead to severe disease and eventually death have not been determined, and a great challenge is the early identification of patients who are more likely to progress to a worse health condition. Studies performed in regions with cyclic outbreaks such as Cuba, Brazil, and Colombia have demonstrated that African ancestry confers protection against severe dengue. Highlighting the host genetics as an important factor in infectious diseases, a large number of association studies between genetic polymorphisms and dengue outcomes have been published in the last two decades. The most widely used approach involves case-control studies with candidate genes, such as the HLA locus and genes for receptors, cytokines, and other immune mediators. Additionally, a Genome-Wide Association Study (GWAS) identified SNPs associated with African ethnicity that had not previously been identified in case-control studies. Despite the increasing number of publications in America, Africa, and Asia, the results are quite controversial, and a meta-analysis is needed to assess the consensus among the studies. SNPs in the MICB, TNF, CD209, FcγRIIA, TPSAB1, CLEC5A, IL10 and PLCE1 genes are associated with the risk or protection of severe dengue, and the findings have been replicated in different populations. A thorough understanding of the viral, human genetic, and immunological mechanisms of dengue and how they interact is essential for effectively preventing dengue, but also managing and treating patients. Copyright © 2017 Elsevier B.V. All rights reserved.

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

    Science.gov (United States)

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

  10. The risk of dengue hemorrhagic fever (DHF) outbreak based on vector density in Kurau, Riau province, Indonesia.

    Science.gov (United States)

    Mangara, S G; Sukmono; Kusumadiharja, J; Suroso, T; Sutjipto, H

    2000-01-01

    It is known that in Padang, Rantau, Rangsang, Merbau and Bengkalis islands, Riau Province, the deposit of oil was found in a huge quantity. The drilling concession belongs to Kondur Petroleum Company. To operate an exploitation, hundreds of workers not only Indonesian but also the workers from foreign countries come and go to that area. It was recorded that the workers from foreign countries come from Singapore, Malaysia, Thailand, The Philippines, Taiwan, Japan, Korea. United States of America and from France, Britain, Australia and Germany. These workers have a close interaction with about 50,00 local population distributed with a high concentration in some places. The high risk of DHF was determined since the significant density of Aedes aregypti larvae, the main vector of DHF, were found in Lukit, Mengkikip and Melibur, three locations of survey. Of 104 (53.3%) of 195 houses in these three survey locations were found positive for the larvae. Even though there were no positive of larvae in 65 houses in Lukit, in Melibur and Mengkikip, the House Index (HI) was 61.7% and 95.7%. Outside the houses 521 containers were examined in three locations of survey and 329 (63.1%) were positive for Ae. aegypti larvae. The highest number of containers positive for Ae. aegypti larvae were 213 (94.7%) out of 225 and found in Mengkikip. In Melibur, 114 (68.3%) out of 167 of containers were positive and in Lukit only 2 (1.56%) out of 129 containers were positive of Ae. aegypti larvae. These larvae density constitute a high risk of DHF outbreak, and unfortunately is supported by the rainfall situation recorded in Kurau and BZ Climatology Stations. It was recorded that all along the year, at least one day in a month there was the rain which the rainfall volume was 30 ml.

  11. Aedes albopictus (Skuse, 1894 infected with the American-Asian genotype of dengue type 2 virus in Medellín suggests its possible role as vector of dengue fever in Colombia

    Directory of Open Access Journals (Sweden)

    Andrés Gómez-Palacio

    2017-03-01

    Conclusion: We report the presence Ae. albopictus naturally infected with the Asian-American genotype of DENV-2 in Colombia. The presence of Ae. albopictus specimens carrying the most common genotype infecting humans in a highly populated city such as Medellín indicates its potential role as dengue vector in Colombia and highlights the relevance of including it in current vector surveillance strategies.

  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. 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.

  14. 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

  15. Active metabolites of the genus Piper against Aedes aegypti: natural alternative sources for dengue vector control

    OpenAIRE

    Marques, André M; Kaplan, Maria Auxiliadora C

    2015-01-01

    The mosquito, Aedes aegypti, is the principal vector of the viruses responsible for dengue and dengue hemorrhagic fevers. The mosquito is widespread throughout tropical and sub-tropical regions; its prevalence makes dengue one of the most important mosquito-borne viral diseases in the world occurring annually in more than 100 endemic countries. Because blood is essential to their development cycle, the Aedes species maintains a close association with humans and their dwellings. Fittingly, the...

  16. Impaired fibrinolysis in the pathogenesis of dengue hemorrhagic fever.

    NARCIS (Netherlands)

    Gorp, E. van; Setiati, T.E.; Mairuhu, A.T.; Suharti, C.; Cate, H.H.; Dolmans, W.M.V.; Meer, J.W.M. van der; Hack, C.E.; Brandjes, D.P.

    2002-01-01

    The mechanisms contributing to bleeding complications in dengue hemorrhagic fever were studied by investigating the pattern of activation of the coagulation and fibrinolytic systems in 50 children with severe dengue hemorrhagic fever. Thirteen patients (26%) died, and activation of coagulation was

  17. Impaired fibrinolysis in the pathogenesis of dengue hemorrhagic fever

    NARCIS (Netherlands)

    van Gorp, Eric C. M.; Setiati, Tatty E.; Mairuhu, Albert T. A.; Suharti, Catharina; Cate Ht, Hugo ten; Dolmans, Wil M. V.; van der Meer, Jos W. M.; Hack, C. Erik; Brandjes, Dees P. M.

    2002-01-01

    The mechanisms contributing to bleeding complications in dengue hemorrhagic fever were studied by investigating the pattern of activation of the coagulation and fibrinolytic systems in 50 children with severe dengue hemorrhagic fever. Thirteen patients (26%) died, and activation of coagulation was

  18. 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

  19. Dengue fever associated with acute scrotal oedema: two case reports

    International Nuclear Information System (INIS)

    Shamim, M.; Naqvi, S.Z.G.

    2011-01-01

    Scrotal oedema associated with dengue fever is a rare and self limiting condition resolving in a few days without any complication or sequelae. This is a report of two cases of dengue fever associated with acute scrotal and penile oedema. (author)

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

    NARCIS (Netherlands)

    Phuong, Hoang Lan; de Vries, Peter J.; Nga, Tran T. T.; Giao, Phan T.; Hung, Le Q.; Binh, Tran Q.; Nam, Nguyen V.; Nagelkerke, Nico; Kager, Piet 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

  1. 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.

  2. [Current situation and surveillance on dengue fever in China, 2005 - 2007].

    Science.gov (United States)

    Wang, Qin; Xu, Zhen; Dou, Feng-Man; Zhou, Hang; Wang, Xiao-Fang; Yin, Wen-Wu; Li, Qun

    2009-08-01

    To provide scientific evidence for prevention and control program on dengue fever through analyzing the situation of dengue fever in China, from 2005 to 2007. Data was collected from Internet-based National Notifiable Infectious Disease Reporting System, National Enhanced Dengue Fever Surveillance System and field investigation on dengue outbreaks, described and analyzed with descriptively and by SPSS statistical software. There was a total number of 1623 dengue cases (including 1356 laboratory confirmed cases and 267 probable cases) and 1 death case reported in China from 2005 to 2007. Among the identified cases, 151 were imported from foreign countries as the Southeast Asian countries, accounting for 9.3%, while the rest 1472 cases were reported from local infections, identified only in 9 cities from Guangdong and Fujian provinces. Data from the monitoring program on Aedes Mosquitoes indicated that: The indicators of BI from 84.6% of the sentinels were over 5, and BI from 72.2% of the sentinels were over 10. This index was especially at a higher level during summer in the southern areas of China. Aedes albopictus was found in all the sentinel sites while Aedes aegypti was only found in Hainan and in limited counties of Guangdong. No dengue virus was isolated from mosquito vectors collected from national sentinel sites, whereas positive results had been detected by PCR test in Guangdong province. It was assumed that a sustainable local circulation of dengue virus had not yet been established successfully in Mainland China according to the surveillance data. However, more local outbreaks reported in Guangdong and Fujian with the wide distribution and high-level density of aedes mosquito, low antibody level in healthy population and the increasing number of imported dengue cases, there is a potential of Dengue outbreaks in southern China. An integrated mosquito vector monitoring and management system is needed in high risk area to reduce the transmission of dengue

  3. 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

    this review, a literature search was made on Pubmed and on the World Health Organization (WHO and PAHO websites using the terms dengue and dengue shock syndrome. This information was complemented with personal practice. SUMMARY OF THE FINDINGS: Dengue is the most important arthropod-borne viral disease of humans. Its presentation is protean and varies from an undifferentiated viral syndrome to hemorrhagic fever and severe shock. Dengue fever is a self-limiting, nonspecific illness characterized by fever, headache, myalgia, and constitutional symptoms. Its severe forms (hemorrhagic fever and shock syndrome may lead to multisystem involvement and death. Early diagnosis, close monitoring for deterioration and response to treatment are necessary in all cases. WHO has provided a stepwise approach to management that is useful for milder forms and early shock. In the more severe forms aggressive fluid resuscitation and support for failing organs is necessary for the critically ill patient. Research addressing pathophysiological differences between dengue shock and septic shock, choice of fluids, inotropes and techniques of organ support are likely to yield benefits for the critically ill. CONCLUSIONS: There is no specific therapy for dengue infections. Good supportive care may be lifesaving, but ultimately initiatives aimed at vector control and prevention of mosquito bites may provide the greatest benefits.

  4. FEVER AS INDICATOR TO SECONDARY INFECTION IN DENGUE VIRAL INFECTION

    Directory of Open Access Journals (Sweden)

    Soegeng Soegijanto

    2018-04-01

    Full Text Available Dengue Virus Infections are distributed in tropical and sub-tropical regions and transmitted by the mosquitoes such as Aedes aegypti and Aedes albopictus. Dengue virus can cause dengue fever, dengue hemorrhagic fever and dengue shock syndrome or dengue and severe dengue classified by World Health Organization. Beside it concurrent infection virus salmonella had been found some cases who showed fever more than 7 days. Concurrent infection with two agents can result in an illness having overlapping symptoms creating a diagnostic dilemma for treating physician, such as dengue fever with typhoid fever. The aim of this research is detection of dengue virus and secondary infection with Salmonella typhi in patients suspected dengue virus infection. Detection of dengue virus and Salmonella typhi using immunochromatography test such as NS1, IgG/IgM for dengue virus infection, and IgM/IgG Salmonella and blood culture. The fifty children with dengue virus infection came to Soerya hospital and 17 cases suspected dengue virus infection, five cases showed a positive NS1 on the second day of fever and one case concurrent with clinical manifestation of convulsi on the third days of fever there were five cases only showed positive. It was showed in this study that on the fourth to six day of fever in dengue virus infection accompanied by antibody IgM & IgG dengue. There were 12 cases showed the clinical manifestation of concurrent dengue viral infection and Salmonella, all of them showed a mild clinical manifestation and did not show plasma leakage and shock. In this study we found the length of stay of concurrent Dengue Virus Infection and Salmonella infection is more than 10 days. These patients were also more likely to have co-existing haemodynamic disturbances and bacterial septicaemia which would have required treatment with inotropes and antibiotics. This idea is very important to make update dengue viral management to decrease mortality in outbreak try to

  5. A case of acute liver failure in dengue hemorrhagic fever

    Directory of Open Access Journals (Sweden)

    Rama Biswas

    2013-07-01

    Full Text Available Dengue is an arboviral disease endemic in many parts of the world. The clinical presentation of dengue viral infection ranges from asymptomatic illness to fatal dengue shock syndrome. Although, it is known to cause hepatic involvement, it occasionally results in acute hepatic failure. We report a case of dengue hemorrhagic fever presenting with acute liver failure. The case recovered completely after treatment. Ibrahim Med. Coll. J. 2013; 7(2: 41-42

  6. Conhecimentos da população sobre dengue, seus vetores e medidas de controle em São José do Rio Preto, São Paulo The population's knowledge concerning dengue fever, vectors, and control measures in São José do Rio Preto, São Paulo state

    Directory of Open Access Journals (Sweden)

    Francisco Chiaravalloti Neto

    1997-09-01

    Full Text Available Desde 1985, vêm sendo realizadas, pelos órgãos de saúde, campanhas educativas institucionais para esclarecer a população sobre dengue, seus vetores e medidas de controle a serem adotadas. Para medir o nível de conhecimento da população de São José do Rio Preto, SP, aplicou-se, nos meses de abril e maio de 1995, um inquérito domiciliar em uma amostra de 537 residências da área urbana da cidade, entrevistando-se mesmo número de mulheres com perguntas sobre dengue, seus vetores e medidas de controle. Os conhecimentos demonstrados foram bastante satisfatórios, com exceção daqueles sobre a doença hemorrágica. Essa aquisição de conhecimentos, entretanto, não tem sido acompanhada da adoção das medidas de controle necessárias e não foi suficiente para a diminuição dos níveis de infestação dos vetores da dengue no município.Educational campaigns to inform the population about dengue fever, vectors, and related control measures have been carried out since 1985 by health services. In order to assess knowledge levels in São José do Rio Preto, São Paulo, a household survey was performed with a sample of 537 households in the urban area of São José do Rio Preto, São Paulo, in April and May 1995, where the same number of women were interviewed with questions about dengue fever, vectors, and control measures. Knowledge as displayed was satisfactory, except for that concerning hemorrhagic dengue. However, acquisition of knowledge was not followed by adoption of necessary control measures was insufficient to decrease infestation rates for dengue vectors in the city.

  7. 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.

  8. Impact of Climate on the incidence of Dengue Haemorrhagic fever in Semarang City

    Science.gov (United States)

    Khairunisa, Ummi; Endah Wahyuningsih, Nur; Suhartono; Hapsari

    2018-05-01

    Dengue Haemorrhagic Fever (DHF) is one of major health problems in Indonesia. DHF is a caused by the dengue virus and potentially deadly infection spread by some mosquitos. The mosquito Aedes aegypti is the main species that spreads this disease. The incidence rate of dengue haemorrhagic fever was still increased in 2011 to 2015 in Indonesia. Dengue viruses and their mosquito vectors are sensitive to their environment. Temperature, rainfall and humidity have well-define roles in the transmission cycle. Therefore changes in these conditions may contribute to increasing incidence. The aim of this study was to analyze the relationship between climate factors and the incidence rate of dengue hemorrhagic fever in Semarang City. The type of research was analytic with cross sectional study. The sample used is the climate data from Meteorology, Climatology and Geophysics Agency (BMKG) and the number of dengue cases from Health Office in Semarang City from 2011 to 2016. Data were analyzed using Pearson trials with α=0,05. Base on this study here air temperature and relative humidity were moderate correlation with negative direction on air temperature (p = 0,000 and r = -0, 429), weakly correlation with positive direction on rainfall (p = 0,014 and r = 0,288) and humidity (p=0,001 and r = 0,382) with dengue hemorrhagic fever incidence in Semarang City. The conclusions of this study there were correlation between climate (air temperature, rainfall, and relative humidity) and DHF in Semarang City in 2011-2016.

  9. 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

  10. 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.

  11. 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.

  12. 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.

  13. 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.

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

    Science.gov (United States)

    Wong, Li Ping; AbuBakar, Sazaly

    2013-01-01

    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. 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. 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. 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.

  15. 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

  16. Oral receptivity of Aedes aegypti from Cape Verde for yellow fever, dengue, and chikungunya viruses.

    Science.gov (United States)

    Vazeille, Marie; Yébakima, André; Lourenço-de-Oliveira, Ricardo; Andriamahefazafy, Barrysson; Correira, Artur; Rodrigues, Julio Monteiro; Veiga, Antonio; Moreira, Antonio; Leparc-Goffart, Isabelle; Grandadam, Marc; Failloux, Anna-Bella

    2013-01-01

    At the end of 2009, 21,313 cases of dengue-3 virus (DENV-3) were reported in the islands of Cape Verde, an archipelago located in the Atlantic Ocean 570 km from the coast of western Africa. It was the first dengue outbreak ever reported in Cape Verde. Mosquitoes collected in July 2010 in the city of Praia, on the island of Santiago, were identified morphologically as Aedes aegypti formosus. Using experimental oral infections, we found that this vector showed a moderate ability to transmit the epidemic dengue-3 virus, but was highly susceptible to chikungunya and yellow fever viruses.

  17. Fundus Findings in Dengue Fever: A Case Report

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    Berna Şahan

    2015-10-01

    Full Text Available 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. (Turk J Ophthalmol 2015; 45: 223-225

  18. 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.

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

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    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

  20. Spatio-Temporal modelling of Dengue Fever in Zulia state, Venezuela

    OpenAIRE

    Cabrera, Maritza

    2014-01-01

    Over half of the world's population are at risk of infection from dengue fever (Guha-Sapir2005). This viral disease is transmitted by the female Aedes aegypti mosquito and is the major source of human death in the world when compared with any other vector borne disease (Gubler1998a). The first important epidemic of dengue haemorrhagic fever (DHF) in America was reported in Cuba in 1981 and subsequently in Venezuela during 1989 and 1990 (Oletta2006, Brightmer1998). There has been a trend of in...

  1. Advances in the development of vaccines for dengue fever

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    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

  2. Deteksi Penyakit Dengue Hemorrhagic Fever dengan Pendekatan One Class Classification

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    Zida Ziyan Azkiya

    2017-10-01

    Full Text Available Two class classification problem maps input into two target classes. In certain cases, training data is available only in the form of a single class, as in the case of Dengue Hemorrhagic Fever (DHF patients, where only data of positive patients is available. In this paper, we report our experiment in building a classification model for detecting DHF infection using One Class Classification (OCC approach. Data from this study is sourced from laboratory tests of patients with dengue fever. The OCC methods compared are One-Class Support Vector Machine and One-Class K-Means. The result shows SVM method obtained precision value = 1.0, recall = 0.993, f-1 score = 0.997, and accuracy of 99.7% while the K-Means method obtained precision value = 0.901, recall = 0.973, f- 1 score = 0.936, and accuracy of 93.3%. This indicates that the SVM method is slightly superior to K-Means for One-Class Classification of DHF patients.

  3. 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...

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

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    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.

  5. 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.

  6. Potential distribution of dengue fever under scenarios of climate change and economic development.

    Science.gov (United States)

    Aström, Christofer; Rocklöv, Joacim; Hales, Simon; Béguin, Andreas; Louis, Valerie; Sauerborn, Rainer

    2012-12-01

    Dengue fever is the most important viral vector-borne disease with ~50 million cases per year globally. Previous estimates of the potential effect of global climate change on the distribution of vector-borne disease have not incorporated the effect of socioeconomic factors, which may have biased the results. We describe an empirical model of the current geographic distribution of dengue, based on the independent effects of climate and gross domestic product per capita (GDPpc, a proxy for socioeconomic development). We use the model, along with scenario-based projections of future climate, economic development, and population, to estimate populations at risk of dengue in the year 2050. We find that both climate and GDPpc influence the distribution of dengue. If the global climate changes as projected but GDPpc remained constant, the population at risk of dengue is estimated to increase by about 0.28 billion in 2050. However, if both climate and GDPpc change as projected, we estimate a decrease of 0.12 billion in the population at risk of dengue in 2050. Empirically, the geographic distribution of dengue is strongly dependent on both climatic and socioeconomic variables. Under a scenario of constant GDPpc, global climate change results in a modest but important increase in the global population at risk of dengue. Under scenarios of high GDPpc, this adverse effect of climate change is counteracted by the beneficial effect of socioeconomic development.

  7. Stability Analysis Susceptible, Exposed, Infected, Recovered (SEIR) Model for Spread Model for Spread of Dengue Fever in Medan

    Science.gov (United States)

    Side, Syafruddin; Molliq Rangkuti, Yulita; Gerhana Pane, Dian; Setia Sinaga, Marlina

    2018-01-01

    Dengue fever is endemic disease which spread through vector, Aedes Aegypty. This disease is found more than 100 countries, such as, United State, Africa as well Asia, especially in country that have tropic climate. Mathematical modeling in this paper, discusses the speed of the spread of dengue fever. The model adopting divided over four classes, such as Susceptible (S), Exposed (E), Infected (I) and Recovered (R). SEIR model further analyzed to detect the re-breeding value based on the number reported case by dengue in Medan city. Analysis of the stability of the system in this study is asymptotically stable indicating a case of endemic and unstable that show cases the endemic cases. Simulation on the mathematical model of SEIR showed that require a very long time to produce infected humans will be free of dengue virus infection. This happens because of dengue virus infection that occurs continuously between human and vector populations.

  8. Método de varredura para exame de criadouros de vetores de dengue e febre amarela urbana Sweeping method to scan breeding places for dengue and urban yellow fever vectors

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    Roseane Lieko Kubota

    2003-04-01

    Full Text Available Com objetivo de estimar o número mínimo de varreduras para coletar uma amostra representativa das larvas presentes em um grande recipiente, foram adicionadas 200 larvas de quarto estádio em um tambor de 80 litros de água. Com auxílio de peneira plástica, foram feitas dez varreduras em cada réplica do experimento. Os resultados indicaram que oito varreduras foram suficientes para coletar até 72% do total de 200 larvas de quarto estadio presentes no criadouro, ou seja, uma média de 143±1,97. A técnica mostrou ser de fácil e eficiente execução quanto à inspeção de criadouros com grande volume de água. Isto reforça sua utilização como instrumento com grande potencial para vigilância vetorial na rotina dos programas de controle de vetores do dengue e febre amarela.To estimate the minimum numbers of "sweepings" for a representative sampling of larvae in a large container. 200 larvae in 4th stage were added in an 80-liter drum to carry out the experiment, in each retort was made 10 sweepings using a plastic sieve. Two hundred larvae in stage 4 were added to an 80-liter-drum and using a plastic sieve10 sweepings were carried out in each experiment replicate. The results showed that 8 sweepings were enough to collect up to 72% of the total sample in the container, i.e., an average of 143±1.97. The proposed method proved to be easily and effectively implemented and allowed for the inspection of containers with large water volumes. These findings reinforce its use as an important potential tool in the routine vectorial surveillance of control programs of dengue and yellow fever.

  9. [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

    2017-12-01

    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.

  10. The correlation between temperature and humidity with the population density of Aedes aegypti as dengue fever’s vector

    Science.gov (United States)

    Sintorini, M. M.

    2018-01-01

    The weather change in South East Asia have triggered the increase of dengue fever illness in Indonesia. Jakarta has been declared as one of dengue fever endemic region. This research aim to gain the dynamic of dengue fever incidents related to temperature, humidity and the population density of Aedes aegypti. This research implementated Design of Ecology Study. The samples were collected from April 2015 to March 2016, from houses located in the suburbs i.e. Pasar Minggu, Ciracas, Sunter Agung, Palmerah and Bendungan Hilir. The sampling based on Sampling Design Cluster and each suburb represents 153 samples. The research shows correlation between temperature (p value 0.000) and humidity (p value 0,000) with Aedes aegypti as dengue fever’s Vector. Therefore, an early warning system should be developed based on environmental factors to anticipate the spread of dengue fever.

  11. 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.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Science.gov (United States)

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

    2014-01-01

    The endemicity of dengue fever (DF) and, consequently, sequelae of DF are increasing worldwide. The increases are largely a result of widespread international travel and the increased range of the mosquito vectors. US Army Special Operations Command (USASOC) personnel are at an increased risk of exposure to dengue based on their frequent deployments to and presence in dengue endemic areas worldwide. Repeated deployments to different endemic areas can increase the risk for developing the more serious sequelae of dengue: dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS). Information about the seroprevalence rate of dengue in USASOC personnel, in particular, is lacking and is critical to assessing the risk, tailoring preventive medicine countermeasures, leveraging field diagnostics, and maintaining mission capability. In the first part of a two-part project to assess baseline seroprevalence in USASOC units, a random, unit-stratified sample of 500 anonymous serum specimens from personnel assigned to the highest-risk units in USASOC were screened for dengue using a microneutralization assay. Of the 500 specimens screened, 56 (11.2%) of 500 had neutralizing titers (NT) (MN₅₀≥10) against at least one DENV serotype. Subsequent sample titration resulted in 48 (85.7%) of 56 of the samples with NT (MN₅₀≥10) against at least one dengue serotype for an overall dengue exposure rate of 9.6% (48 of 500). The second part of the ongoing project, started in 2012, was a multicenter, serosurveillance project using predeployment and postdeployment sera collected from USASOC personnel deployed to South and Central America, Africa, and Southeast Asia. Preliminary results show a 13.2% (55 of 414) seropositivity rate. The significance of these findings as they relate to personal risk and operational impact is discussed. 2014.

  14. Socio-economic and Climate Factors Associated with Dengue Fever Spatial Heterogeneity: A Worked Example in New Caledonia

    Science.gov (United States)

    Teurlai, Magali; Menkès, Christophe Eugène; Cavarero, Virgil; Degallier, Nicolas; Descloux, Elodie; Grangeon, Jean-Paul; Guillaumot, Laurent; Libourel, Thérèse; Lucio, Paulo Sergio; Mathieu-Daudé, Françoise; Mangeas, Morgan

    2015-01-01

    Background/Objectives Understanding the factors underlying the spatio-temporal distribution of infectious diseases provides useful information regarding their prevention and control. Dengue fever spatio-temporal patterns result from complex interactions between the virus, the host, and the vector. These interactions can be influenced by environmental conditions. Our objectives were to analyse dengue fever spatial distribution over New Caledonia during epidemic years, to identify some of the main underlying factors, and to predict the spatial evolution of dengue fever under changing climatic conditions, at the 2100 horizon. Methods We used principal component analysis and support vector machines to analyse and model the influence of climate and socio-economic variables on the mean spatial distribution of 24,272 dengue cases reported from 1995 to 2012 in thirty-three communes of New Caledonia. We then modelled and estimated the future evolution of dengue incidence rates using a regional downscaling of future climate projections. Results The spatial distribution of dengue fever cases is highly heterogeneous. The variables most associated with this observed heterogeneity are the mean temperature, the mean number of people per premise, and the mean percentage of unemployed people, a variable highly correlated with people's way of life. Rainfall does not seem to play an important role in the spatial distribution of dengue cases during epidemics. By the end of the 21st century, if temperature increases by approximately 3°C, mean incidence rates during epidemics could double. Conclusion In New Caledonia, a subtropical insular environment, both temperature and socio-economic conditions are influencing the spatial spread of dengue fever. Extension of this study to other countries worldwide should improve the knowledge about climate influence on dengue burden and about the complex interplay between different factors. This study presents a methodology that can be used as a

  15. 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

  16. Dengue vector control: present status and future prospects.

    Science.gov (United States)

    Yap, H H; Chong, N L; Foo, A E; Lee, C Y

    1994-12-01

    Dengue Fever (DF) and Dengue Haemorrhagic Fever (DHF) have been the most common urban diseases in Southeast Asia since the 1950s. More recently, the diseases have spread to Central and South America and are now considered as worldwide diseases. Both Aedes aegypti and Aedes albopictus are involved in the transmission of DF/DHF in Southeast Asian region. The paper discusses the present status and future prospects of Aedes control with reference to the Malaysian experience. Vector control approaches which include source reduction and environmental management, larviciding with the use of chemicals (synthetic insecticides and insect growth regulators and microbial insecticide), and adulticiding which include personal protection measures (household insecticide products and repellents) for long-term control and space spray (both thermal fogging and ultra low volume sprays) as short-term epidemic measures are discussed. The potential incorporation of IGRs and Bacillus thuringiensis-14 (Bti) as larvicides in addition to insecticides (temephos) is discussed. The advantages of using water-based spray over the oil-based (diesel) spray and the use of spray formulation which provide both larvicidal and adulticidal effects that would consequently have greater impact on the overall vector and disease control in DF/DHF are highlighted.

  17. Frequency of splenomegaly in dengue fever in children

    International Nuclear Information System (INIS)

    Javaid, A.; Asghar, M.; Butt, M.A.

    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. Methods: 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 IgM 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. Results: 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 37 (39.78%) followed by bleeding manifestations and upper respiratory tract infection (upper RTI). Splenomegaly was seen in 45 (48.4%) children. Conclusion: Dengue fever is increasingly presenting with atypical presentation like splenomegaly, encephalopathy, bleeding manifestations and upper RTI. (author)

  18. 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.

  19. [Epidemiologic surveillance of dengue fever in the French army from 1996 to 1999].

    Science.gov (United States)

    Meynard, J B; Ollivier-Gay, L; Deparis, X; Durand, J P; Michel, R; Pages, F; Matton, T; Boutin, J P; Tolou, H; Merouze, F; Baudon, D

    2001-01-01

    Dengue fever is a widespread disease that can occur outside tropical areas. Several thousand French military personnel are exposed to this infectious risk each year and exposure is expected to rise with the creation of a professional army and the increasing number of foreign missions. As a result, dengue fever has become a major priority for the Armed Services Health Corps (ASHC). A system of epidemiological surveillance based on the active participation of all military physicians has been designed by the ASHC to collect and analyze all data relevant to cases of dengue fever involving French military personnel stationed overseas or at home. The purpose of this study is to present data compiled for the period from 1996 to 1999. Analysis of these data demonstrated that the incidence of dengue fever peaked in 1997 due to epidemic outbreaks occurring in French Polynesia and Martinique. In response to these outbreaks control measures were adapted especially in regard to vector control. This study shows that the system of surveillance implemented by the ASHC is an effective but still perfectible tool.

  20. A novel indirect ELISA for diagnosis of dengue fever

    Directory of Open Access Journals (Sweden)

    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.

  1. Dengue fever with hepatitis E and hepatitis A infection.

    Science.gov (United States)

    Yakoob, Javed; Jafri, Wasim; Siddiqui, Shaheer; Riaz, Mehmood

    2009-03-01

    Infection with dengue viruses produces a spectrum of clinical illness ranging from a nonspecific viral syndrome to severe and fatal haemorrhagic disease. Important risk factors include the strain and serotype of the infecting virus, as well as the age, immune status, and genetic predisposition of the patient. The teaching point in this case study was Dengue fever which occurred concomitantly with Hepatitis A and Hepatitis E virus infection.

  2. Cardiac tamponade in a patient with severe dengue fever

    Directory of Open Access Journals (Sweden)

    Ana Isabel Vieira Fernandes

    Full Text Available Abstract A 26-year-old postpartum female presented with symptoms characteristic of dengue fever on the 16th day of puerperium. On the third day of the illness, the patient presented a clinical picture consistent with shock. Tests determined primary infection with dengue virus serotype 2. Cardiac tamponade was confirmed by echocardiography. This rare manifestation is described in a patient without any associated comorbidity.

  3. 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

  4. Environmentally-driven ensemble forecasts of dengue fever

    Science.gov (United States)

    Yamana, T. K.; Shaman, J. L.

    2017-12-01

    Dengue fever is a mosquito-borne viral disease prevalent in the tropics and subtropics, with an estimated 2.5 billion people at risk of transmission. In many areas where dengue is found, disease transmission is seasonal but prone to high inter-annual variability with occasional severe epidemics. Predicting and preparing for periods of higher than average transmission remains a significant public health challenge. Recently, we developed a framework for forecasting dengue incidence using an dynamical model of disease transmission coupled with observational data of dengue cases using data-assimilation methods. Here, we investigate the use of environmental data to drive the disease transmission model. We produce retrospective forecasts of the timing and severity of dengue outbreaks, and quantify forecast predictive accuracy.

  5. Ocular manifestations of dengue fever in an East Indian epidemic.

    Science.gov (United States)

    Kapoor, Harpreet K; Bhai, Saloni; John, Mary; Xavier, Jai

    2006-12-01

    The incidence and geographic distribution of dengue has increased dramatically in recent years. Previously, ocular findings in dengue fever were considered rare. We report a spectrum of ocular manifestations of this potentially fatal disease and its association with laboratory parameters. 134 patients hospitalized with a diagnosis of dengue fever during an epidemic were included. Systemic and ophthalmic examinations were completed on all patients. The mean age was 31.3 years and 63.4% were males. All patients presented with fever. Six (4.5%) patients had retrobulbar pain and none of the patients presented with any visual complaints. Ocular findings were present in 54 (40.3%) patients. Subconjunctival haemorrhage was the commonest eye finding seen in 50 patients, of whom 84% had characteristic petechial type of haemorrhages. Fundus findings present in 10 (7.5%) patients included dilatation and tortuosity of vessels, superficial retinal haemorrhages, cotton-wool spots, and hard exudates; the macula, however, was spared in all patients. Only 6 of the patients with posterior segment involvement returned for follow-up examination and it was found that retinal changes had resolved without any specific treatment within 2 to 8 weeks time. Of all laboratory parameters evaluated, marked thrombocytopenia (platelet count petechial type, are a common manifestation of dengue infection. Dengue fever patients with marked thrombocytopenia are predisposed to spontaneous ocular haemorrhages.

  6. Myalgia Cruris Epidemica: an unusual presentation of dengue fever.

    Science.gov (United States)

    Ahmad, Rashidi; Abdul Latiff, Abdul Kursi; Abdul Razak, Salmi

    2007-11-01

    We describe a 5-year-old girl who had sudden onset difficulty in walking after 3 days of febrile illness. In the emergency department her creatine kinase level was elevated but urine myoglobin was normal. She was diagnosed as having benign acute childhood myositis. Because of poor oral intake and dehydration, she was admitted to the pediatric ward. The next day she had a petechial rash over the antecubital fossa, and dengue IgM back was positive. She was treated conservatively and recovered uneventfully. Despite dengue fever being endemic in Malaysia, this is the first case report of myositis following dengue infection in Malaysia.

  7. 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

  8. Assessing socioeconomic vulnerability to dengue fever in Cali, Colombia: statistical vs expert-based modeling

    OpenAIRE

    Hagenlocher, Michael; Delmelle, Eric; Casas, Irene; Kienberger, Stefan

    2013-01-01

    Background As a result of changes in climatic conditions and greater resistance to insecticides, many regions across the globe, including Colombia, have been facing a resurgence of vector-borne diseases, and dengue fever in particular. Timely information on both (1) the spatial distribution of the disease, and (2) prevailing vulnerabilities of the population are needed to adequately plan targeted preventive intervention. We propose a methodology for the spatial assessment of current socioecon...

  9. Epidemiological, clinical and climatic characteristics of dengue fever in Kaohsiung City, Taiwan with implication for prevention and control.

    Science.gov (United States)

    Chang, Chiu-Jung; Chen, Colin S; Tien, Chien-Jung; Lu, Mei-Rou

    2018-01-01

    The early identification of dengue infection is essential for timely and effective quarantine and vector control measures for preventing outbreaks of the disease. Kaohsiung City is responsible for most of the dengue cases in Taiwan. Thus, this study aims to identify major factors involved in the prevalence of dengue fever by analyzing the epidemiological and clinical characteristics, and to establish associations between weather parameters and dengue occurrence in this City. A retrospective study was conducted with 3,322 confirmed dengue cases. Appropriate statistical methods were used to compare differences and correlations between dengue occurrence and demographic, clinical and weather parameters. The outbreak of dengue fever was found to be initiated by imported cases of dengue viruses from other endemic countries. Most of the confirmed cases were not reported to the health authority during the first visit to a doctor, and it took a median of 5 days after the appearance of the first syndromes for medical personnel to report suspected dengue cases. Accordingly, Aedes mosquitoes would have enough time to be infected and transmit the dengue virus. The diagnosis and notification criteria should not only include common symptoms of fever, myalgia, headache, skin rash and arthralgia, but should also be adjusted to include the most frequent symptoms of loss of appetite and feeling thirsty to shorten the notification time. Significantly positive correlations were found between the number of confirmed cases and weather parameters (i.e., temperature, rainfall and relative humidity) at a time lag of 1 month and 2 months. The predictive models for dengue occurrence using these three parameters at a 2-month lag time were established. The surveillance of imported cases, adjustment of notification criteria and application of climatic predictive models would be helpful in strengthening the dengue early warning surveillance system.

  10. Therapeutic antibodies as a treatment option for dengue fever.

    Science.gov (United States)

    Chan, Kuan Rong; Ong, Eugenia Z; Ooi, Eng Eong

    2013-11-01

    Dengue fever is the most prevalent mosquito-borne viral disease globally with about 100 million cases of acute dengue annually. Severe dengue infection can result in a life-threatening illness. In the absence of either a licensed vaccine or antiviral drug against dengue, therapeutic antibodies that neutralize dengue virus (DENV) may serve as an effective medical countermeasure against severe dengue. However, therapeutic antibodies would need to effectively neutralize all four DENV serotypes. It must not induce antibody-dependent enhancement of DENV infection in monocytes/macrophages through Fc gamma receptor (FcγR)-mediated phagocytosis, which is hypothesized to increase the risk of severe dengue. Here, we review the strategies and technologies that can be adopted to develop antibodies for therapeutic applications. We also discuss the mechanism of antibody neutralization in the cells targeted by DENV that express Fc gamma receptor. These studies have provided significant insight toward the use of therapeutic antibodies as a potentially promising bulwark against dengue.

  11. Dengue fever/dengue haemorrhagic fever in Filipino children: clinical experience during the 1983-1984 epidemic.

    Science.gov (United States)

    Songco, R S; Hayes, C G; Leus, C D; Manaloto, C O

    1987-09-01

    A total of 377 Filipino children out of a total of 5,427 admissions from October 31, 1983 to March 31, 1984 were found to have dengue fever/dengue haemorrhagic fever The present clinical presentation of these infections was basically similar to that in previous epidemics but hepatomegaly and pleural effusion were less frequent and cardiac involvement, more frequent. The discrepancies between the clinical syndromes and HI antibody responses were evident; thus, the values used for the interpretation of the antibody titers must be reassessed.

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

    OpenAIRE

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

    2017-01-01

    Background 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...

  13. LARVAE DENSITY OF DENGUE HEMORRHAGIC FEVER (DHF VECTOR Aedes sp. IN ENDEMIC, SPORADIC AND POTENTIAL AREA IN SEMARANG CITY, CENTRAL JAVA PROVINCE

    Directory of Open Access Journals (Sweden)

    Eva Lestari

    2015-01-01

    Full Text Available Demam Berdarah Dengue (DBD adalah penyakit menular yang disebabkan oleh virus Dengue dan ditularkan oleh nyamukAedes aegypti. Kota Semarang merupakan daerah endemis DBD dengan jumlah kasus sebanyak 5.538 kasus,IR 36,75/10.000 penduduk dan CFR 0,8% (tahun 2010. Data kepadatan vektor dapat digunakan untuk menentukan tindakanpengendalian vektor yang tepat. Tujuan dari penelitian ini adalah untuk menghitung HI, CI, BI, DF, dan Angka Bebas Jentik(ABJ Aedes sp. di daerah endemis, sporadis dan potensial DBD. Jenis penelitian deskriptif dengan pendekatan crosssectional. Metode pelaksanaan survei jentik dengan single larva. Populasi adalah seluruh rumah di KelurahanSendangmulyo, Terboyo Wetan, dan Pesantren. Pengambilan sampel penelitian menggunakan metode purposif. Hasilpenelitian menunjukkan bahwa angka HI (53,75%, CI (30,77%, BI (75%, dan DF (7 tertinggi di Kelurahan TerboyoWetan (sporadis. Angka ABJ di semua lokasi penelitian < 95%. Kepadatan jentik daerah sporadis lebih tinggi dibandingdaerah endemis DBD. Kepadatan jentik tidak berkorelasi dengan stratifikasi endemisitas wilayah DBD.Kata kunci: kepadatan jentik, endemis, sporadis, potensial, DBD

  14. A PATIENT DENGUE HEMORRHAGIC FEVER WITH SPASMS

    Directory of Open Access Journals (Sweden)

    Ulfa Kholili

    2014-09-01

    Full Text Available Indonesia is one of the countries with the high endemic of Dengue viral infection followed by Thailand, Myanmar, India and Srilanka. For more 10-15 years, Dengue Viral Infection/DHF has become a cause of patient who should be hospitalized and was the first cause of death children in south easthern Asia.1,2 Batavia was the first city of Indonesia found Dengue Viral infection which had been written in journal by David Bylon in the 1779. Encephalopathy of dengue (ED is one unusually complication of dengue viral infection which had been characterized by aberration the arrangement of nerves central (CNS. This paper want to describe of a young teenage with suffer from DHF and seizure. Beside it, pleural effusion and cerebral edema had been found. Seizure most likely due to dengue encephalopathy associated with cerebral edema and was supported by positive IgG and IgM anti dengue. Corticosteroid was given to improve cerebral edema. By good management as long as admission, she was discharged from hospital with a good condition.

  15. Estimation of the Basic Reproductive Ratio for Dengue Fever at the Take-Off Period of Dengue Infection.

    Science.gov (United States)

    Jafaruddin; Indratno, Sapto W; Nuraini, Nuning; Supriatna, Asep K; Soewono, Edy

    2015-01-01

    Estimating the basic reproductive ratio ℛ 0 of dengue fever has continued to be an ever-increasing challenge among epidemiologists. In this paper we propose two different constructions to estimate ℛ 0 which is derived from a dynamical system of host-vector dengue transmission model. The construction is based on the original assumption that in the early states of an epidemic the infected human compartment increases exponentially at the same rate as the infected mosquito compartment (previous work). In the first proposed construction, we modify previous works by assuming that the rates of infection for mosquito and human compartments might be different. In the second construction, we add an improvement by including more realistic conditions in which the dynamics of an infected human compartments are intervened by the dynamics of an infected mosquito compartment, and vice versa. We apply our construction to the real dengue epidemic data from SB Hospital, Bandung, Indonesia, during the period of outbreak Nov. 25, 2008-Dec. 2012. We also propose two scenarios to determine the take-off rate of infection at the beginning of a dengue epidemic for construction of the estimates of ℛ 0: scenario I from equation of new cases of dengue with respect to time (daily) and scenario II from equation of new cases of dengue with respect to cumulative number of new cases of dengue. The results show that our first construction of ℛ 0 accommodates the take-off rate differences between mosquitoes and humans. Our second construction of the ℛ 0 estimation takes into account the presence of infective mosquitoes in the early growth rate of infective humans and vice versa. We conclude that the second approach is more realistic, compared with our first approach and the previous work.

  16. Dengue fever as a cause of hemophagocytic lymphohistiocytosis.

    Science.gov (United States)

    Hein, Noely; Bergara, Gabriel Heiser; Moura, Nathalie Bianchini Vieira; Cardoso, Débora Morais; Hirose, Maki; Ferronato, Angela Espósito; Pastorino, Antônio Carlos; Lo, Denise Swei; Gilio, Alfredo Elias

    2015-01-01

    Dengue is endemic in more than 100 countries in Southeast Asia, the Americas, the western Pacific, Africa and the eastern Mediterranean regions. The virus is transmitted by Aedes mosquitoes. Dengue disease is the most prevalent arthropod-borne viral disease in humans and is a global and national public health concern in several countries. A seasonal pattern of dengue disease is consistently observed. The highest incidences usually correspond to the period of highest rainfall and humidity, providing suitable conditions for Aedes aegypti breeding and survival. In Brazil for instance it is from January to June. Dengue may cause marked changes in bone marrow that result in hypocellularity and, consequently, thrombocytopenia and leucopenia, along with an increase in hematocrit, which is secondary to capillary leakage. However, those abnormalities are usually self-limited, and do not warrant further investigations, such as a marrow biopsy or a myelogram. The occurrence of persistent reactive hemophagocytosis is uncommon and usually leads to serious adverse outcomes. The authors report the case of an 8-year old girl complaining of high-grade fever, malaise, headache, abdominal pain and a cutaneous rash. Laboratory examination revealed atypical lymphocytosis on peripheral blood count, hyperbilirrunemia, abnormal liver enzymes and clotting tests. Serology was positive for dengue. Because of the persistence of fever and laboratory examinations were consistent with hemophagocytic lymphohistiocytosis (HLH) a bone marrow aspiration was performed, which confirmed the presence of hemophagocytosis. Hence we report a rare presentation of dengue accompanied by self-limited HLH that hopefully evolve to favorable outcome.

  17. [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

  18. 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.

  19. 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.

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

    Directory of Open Access Journals (Sweden)

    Deborah Hl Ng

    Full Text Available 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

  1. 20 Years Spatial-Temporal Analysis of Dengue Fever and Hemorrhagic Fever in Mexico.

    Science.gov (United States)

    Hernández-Gaytán, Sendy Isarel; Díaz-Vásquez, Francisco Javier; Duran-Arenas, Luis Gerardo; López Cervantes, Malaquías; Rothenberg, Stephen J

    2017-10-01

    Dengue Fever (DF) is a human vector-borne disease and a major public health problem worldwide. In Mexico, DF and Dengue Hemorrhagic Fever (DHF) cases have increased in recent years. The aim of this study was to identify variations in the spatial distribution of DF and DHF cases over time using space-time statistical analysis and geographic information systems. Official data of DF and DHF cases were obtained in 32 states from 1995-2015. Space-time scan statistics were used to determine the space-time clusters of DF and DHF cases nationwide, and a geographic information system was used to display the location of clusters. A total of 885,748 DF cases was registered of which 13.4% (n = 119,174) correspond to DHF in the 32 states from 1995-2015. The most likely cluster of DF (relative risk = 25.5) contained the states of Jalisco, Colima, and Nayarit, on the Pacific coast in 2009, and the most likely cluster of DHF (relative risk = 8.5) was in the states of Chiapas, Tabasco, Campeche, Oaxaca, Veracruz, Quintana Roo, Yucatán, Puebla, Morelos, and Guerrero principally on the Gulf coast over 2006-2015. The geographic distribution of DF and DHF cases has increased in recent years and cases are significantly clustered in two coastal areas (Pacific and Gulf of Mexico). This provides the basis for further investigation of risk factors as well as interventions in specific areas. Copyright © 2018 IMSS. Published by Elsevier Inc. All rights reserved.

  2. Evolving herbal formulations in management of dengue fever.

    Science.gov (United States)

    Singh, Pawan Kumar; Rawat, Pooja

    Dengue is endemic in more than 100 countries and it is estimated that annually above 390 million infections occur globally. During the period between 1996-2015, a massive increase of more than 500 per cent has been recorded in number of dengue cases reported in India. Till date, there are no specific globally accepted treatments for dengue fever in any system of medicine. Dengue does not cause very high mortality if properly handled and is currently being managed by clinicians through various adjuvant and alternative therapeutic options. Various plant based preparations have been used in different parts of India for combating dengue and are simultaneously also being scientifically validated by researchers. However, number of such scientific validation studies on phytomedicines are very less in India. Out of twenty-two plants reported against dengue, only four have been studied scientifically. Azadirachta indica, Carica papaya, Hippophae rhamnoides and Cissampelos pareira extracts were found effective and demonstrated improvement in clinical symptoms and direct inhibitory effect on dengue virus. C. papaya clinical trial showed increase in platelet count and faster recovery. These plants may be explored further as probable candidates for drug discovery against dengue. There is a need to search more such herbal formulations, which are being practiced at local level, document properly and validate them scientifically to confirm efficacy, mechanistic action and safety, before use. The herbal formulations being used by communities are the low hanging fruits which may provide alternative or adjuvant therapy if proper validation, value addition and product development steps are followed. This paper aims to review the recent status of dengue cases, deaths and evolving curative herbal solutions adapted and reported from India to combat the disease. Copyright © 2017 Transdisciplinary University, Bangalore and World Ayurveda Foundation. Published by Elsevier B.V. All rights

  3. Autoimmune features caused by dengue fever: a case report

    Directory of Open Access Journals (Sweden)

    Denis Leonardo Fontes Jardim

    Full Text Available Dengue virus is the most important mosquito-borne viral disease in the world. Co-circulation of the four types of dengue viruses and expansion of dengue epidemic gave rise to infection enhancement and a big expansion of clinical aspects of the disease. Herein we report a case of a 25-year-old white woman with dengue fever and numerous associated autoimmune features. Our patient had proteinuria, an extensive right pleural effusion, a thin pericardial effusion and ascites. She had a low C3 level and positive antinuclear antibody; cryoglobulins were also positive. The numerous autoimmune features of this patient were a diagnostic challenge, since she was a young woman and could be easily mistaken for a rheumatologic patient in a newly open disease. Dengue infection probably was a triggering event causing an abnormal immune response. Therefore, dengue should be suspected in patients with hematological disorders and autoimmune features in endemic regions or those who have travelled to those regions.

  4. An Accurate Gaussian Process-Based Early Warning System for Dengue Fever

    OpenAIRE

    Albinati, Julio; Meira Jr, Wagner; Pappa, Gisele Lobo

    2016-01-01

    Dengue fever is a mosquito-borne disease present in all Brazilian territory. Brazilian government, however, lacks an accurate early warning system to quickly predict future dengue outbreaks. Such system would help health authorities to plan their actions and to reduce the impact of the disease in the country. However, most attempts to model dengue fever use parametric models which enforce a specific expected behaviour and fail to capture the inherent complexity of dengue dynamics. Therefore, ...

  5. Estratificación de una ciudad hiperendémica en dengue hemorrágico Stratification of a city with hyperendemic dengue hemorrhagic fever

    Directory of Open Access Journals (Sweden)

    Roberto Barrera

    2000-10-01

    Full Text Available La gran heterogeneidad ambiental de viviendas y barrios en los centros urbanos donde se cría Aedes aegypti, principal vector del dengue, junto con la escasez de recursos y de personal entrenado en el control de mosquitos constituyen retos para cualquier iniciativa destinada a controlar el dengue hemorrágico (DH. Una adecuada vigilancia epidemiológica puede servir de base para comenzar a estratificar los centros urbanos e identificar las zonas críticas donde deben concentrarse las tareas de control. En este estudio, se estratificó una ciudad hiperendémica en dengue hemorrágico (Maracay, Venezuela con la ayuda de un sistema de información geográfica (SIG y el análisis de la persistencia, la incidencia y la prevalencia del dengue mediante diagnósticos clínicos registrados de 1993 a 1998. Maracay tiene cerca de un millón de habitantes que viven en unos 349 barrios de 6 poblaciones que integran el Área Metropolitana, donde se notificaron 10 576 casos de dengue, 2 593 casos de DH y 8 defunciones. La incidencia de DH mostró una relación directa con la incidencia del dengue, el número de habitantes y la densidad poblacional. El patrón espacial de la incidencia del dengue fue estable durante los años estudiados y se encontraron relaciones positivas y significativas de la incidencia del dengue por barrio entre pares de años. La persistencia del dengue se relacionó directamente con la incidencia mensual por barrio. Estos patrones espaciales facilitaron la estratificación de la ciudad en tres estratos: 68 barrios sin dengue aparente, 226 barrios con baja persistencia y prevalencia, y 55 barrios con alta persistencia y prevalencia. Se recomienda otorgar alta prioridad de control a estos 55 barrios que ocupan 35% del área urbana y presentaron 70% de todos los casos de dengue.Any effort to control dengue hemorrhagic fever (DHF faces a number of challenges. Among these are the great environmental heterogeneity of homes and neighborhoods

  6. Time-specific ecological niche modeling predicts spatial dynamics of vector insects and human dengue cases.

    Science.gov (United States)

    Peterson, A Townsend; Martínez-Campos, Carmen; Nakazawa, Yoshinori; Martínez-Meyer, Enrique

    2005-09-01

    Numerous human diseases-malaria, dengue, yellow fever and leishmaniasis, to name a few-are transmitted by insect vectors with brief life cycles and biting activity that varies in both space and time. Although the general geographic distributions of these epidemiologically important species are known, the spatiotemporal variation in their emergence and activity remains poorly understood. We used ecological niche modeling via a genetic algorithm to produce time-specific predictive models of monthly distributions of Aedes aegypti in Mexico in 1995. Significant predictions of monthly mosquito activity and distributions indicate that predicting spatiotemporal dynamics of disease vector species is feasible; significant coincidence with human cases of dengue indicate that these dynamics probably translate directly into transmission of dengue virus to humans. This approach provides new potential for optimizing use of resources for disease prevention and remediation via automated forecasting of disease transmission risk.

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

    Directory of Open Access Journals (Sweden)

    Madhavi

    2016-03-01

    investigations were done: Blood counts, IgM Dengue. Clinically, patients were monitored and platelet count, haematocrit, Hess test were repeated daily. DATA ANALYSIS Data collected will be analysed by frequency, percentage and mean. Dengue-IgM Capture ELISA Detection of dengue virus specific IgM Antibodies in serum. RESULTS Male to female ratio was 1.5:1. Majority of the cases having dengue infection belong to the age group of 21-30 years, wherein 48% belong to 21-30 years’ group and 24% belong to 31-40 years’ group. All the cases had fever (100%. Other common signs and symptoms included are myalgia (85%, headache (80%, joint pains (76%, vomiting (60%, pain abdomen (54%, rash (46%, hepatomegaly (25%, bleeding (21% and shock (5%. Signs suggestive of plasma leakage such as pedal oedema (12%, ascites (20%, pleural effusion (26% were present. Hess test was positive in 20% of the patients. Thrombocytopenia was found in 76% patients. Bradycardia was found in 41 %. CONCLUSIONS The present study had an objective of studying clinical manifestations and haematological profile associated with dengue fever. A positive Hess test should prompt close observation and early hospital referral, but a negative test does not exclude dengue infection. Bleeding tendencies should be closely watched for. When features of plasma leakage such as pedal oedema, pleural effusion, ascites are present, the patient should be closely watched for and should be immediately managed. The treatment of dengue is mainly supportive. However, appropriate fluid management plays a major role in outcome of the disease. Dengue sero-surveillance studies may give some idea about advent, intensity, transmission season, seasonal incidence, waxing and waning, and impending epidemic of dengue and DHF. A large-scale active longitudinal sero-survey along with the study of vector capacity and vector competence would provide more correct information. A total of 100 patients admitted to our hospital with fever (>38.50 F and Ig

  8. 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.)

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

    International Nuclear Information System (INIS)

    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. (orig.)

  10. Dengue-yellow fever sera cross-reactivity; challenges for diagnosis

    OpenAIRE

    Houghton-Triviño, Natalia; Montaña, Diana; Castellanos, Jaime

    2008-01-01

    Objective The Flavivirus genera share epitopes inducing cross-reactive antibodies leading to great difficulty in differentially diagnosing flaviviral infections. This work was aimed at evaluating the complexity of dengue and yellow fever serological differential diagnosis. Material and methods Dengue antibody capture ELISA and a yellow fever neutralisation test were carried out on 13 serum samples obtained from yellow fever patients, 20 acute serum samples from dengue patients and 19 voluntan...

  11. Frequency, Pattern and Management of Acute Abdomen in Dengue Fever in Karachi, Pakistan

    OpenAIRE

    Muhammad Shamim

    2010-01-01

    This study aimed to determine the frequency, pattern and management of acute abdomen in patients with dengue fever. Methods: This descriptive case series is a prospective analysis of acute abdomen in dengue fever that was performed at three secondary care hospitals in Karachi, Pakistan from June 1, 2005 to December 31, 2008. The inclusion criterion was all patients with confirmed diagnosis of dengue fever. Patients with incomplete laboratory, ultrasound or histopathology data were excluded...

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

    Directory of Open Access Journals (Sweden)

    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.

  13. The effect of vector control strategy against Dengue transmission between mosquitoes and humans

    Directory of Open Access Journals (Sweden)

    Chen-Xia Yang

    2017-03-01

    Full Text Available With the consideration of mechanism of prevention and control for the spread of dengue fever, a mathematical model of dengue fever dynamical transmission between mosquitoes and humans, incorporating a vector control strategy of impulsive culling of mosquitoes, is proposed in this paper. By using the comparison principle, Floquet theorem and some of analytical methods, we obtain the basic reproductive number $\\mathcal{R}_0$ for this infectious disease, which illustrates the stability of the disease-free periodic solution and the uniform persistence of the disease. Further, the explicit conditions determining the backward or forward bifurcation are obtained and the culling rate $\\phi$ is a major effect on the occurrence of backward bifurcation. Finally, numerical simulations are given to verify the correctness of theoretical results and the most efficiency of vector control strategy.

  14. Skin lesions in hospitalized cases of dengue Fever.

    Science.gov (United States)

    Saleem, Khawer; Shaikh, Irfan

    2008-10-01

    To determine the frequency and types of skin lesions in cases of dengue fever in patients admitted in three hospitals of Karachi. Case series. Three tertiary care hospitals of Karachi, from November 2006 to February 2007. One hundred patients of dengue fever with positive anti-dengue Immunoglobulin M (IgM) serology were included in the study. The admitted patients in PNS Shifa Hospital, Jinnah Postgraduate Medical Centre (JPMC) and Civil Hospital, Karachi were selected for the study. Presenting features were noted. The patients were physically examined for the presence of skin and mucosal lesions and findings were recorded. Total and Differential Leukocyte Count (TLC and DLC), platelet count and Liver Function Tests (LFTs) were done in all the patients. All the patients had low leukocyte and low platelet counts. The common presenting symptoms were high-grade fever with or without rigors, headache, body aches, backache, vomiting, sore throat with cough and generalized weakness (seen in 86% patients). The uncommon presenting features were diarrhea, abdominal pain, bleeding from gums and nosebleeds (seen in 14% patients). Sixty-eight (68%) patients had skin lesions. The most common skin presentation was generalized macular blanchable erythema involving trunk and limbs, seen in 44 (65%) cases. Discrete petechial lesions were seen on various body areas in 24 (35%) cases. Palmer erythema was seen in 20 (30%) patients. Generalized itching was seen in 16 (23%) cases. Isolated itching of palms and soles was seen in 20 (30%) cases. Twenty-eight (28%) patients had deranged LFTs. Out of those, 4 patients had raised serum bilirubin level whereas rest of the 24 had raised ALT. Dengue fever commonly presents with specific skin lesions. The skin lesions can be a clue to the diagnosis in difficult cases.

  15. Skin lesions in hospitalized cases of dengue fever

    International Nuclear Information System (INIS)

    Saleem, K.; Shaikh, I.

    2008-01-01

    To determine the frequency and types of skin lesions in cases of dengue fever in patients admitted in three hospitals of Karachi. One hundred patients of dengue fever with positive anti-dengue Immunoglobulin M (IgM) serology were included in the study. The admitted patients in PNS Shifa Hospital, Jinnah Postgraduate Medical Centre (JPMC) and Civil Hospital, Karachi were selected for the study. Presenting features were noted. The patients were physically examined for the presence of skin and mucosal lesions and findings were recorded. Total and Differential Leukocyte Count (TLC and DLC), platelet count and Liver Function Tests (LFTs) were done in all the patients. All the patients had low leukocyte and low platelet counts. The common presenting symptoms were high-grade fever with or without rigors, headache, body aches, backache, vomiting, sore throat with cough and generalized weakness (seen in 86% patients). The uncommon presenting features were diarrhea, abdominal pain, bleeding from gums and nosebleeds (seen in 14% patients). Sixty-eight (68%) patients had skin lesions. The most common skin presentation was generalized macular blanchable erythema involving trunk and limbs, seen in 44 (65%) cases. Discrete petechial lesions were seen on various body areas in 24 (35%) cases. Palmer erythema was seen in 20 (30%) patients. Generalized itching was seen in 16 (23%) cases. Isolated itching of palms and soles was seen in 20 (30%) cases. Twenty-eight (28%) patients had deranged LFTs. Out of those, 4 patients had raised serum bilirubin level whereas rest of the 24 had raised ALT. Dengue fever commonly presents with specific skin lesions. The skin lesions can be a clue to the diagnosis in difficult cases. (author)

  16. Skin lesions in hospitalized cases of dengue fever

    Energy Technology Data Exchange (ETDEWEB)

    Saleem, K; Shaikh, I [Jinnah Postgraduate Medical Hospital, Karachi (Pakistan)

    2008-10-15

    To determine the frequency and types of skin lesions in cases of dengue fever in patients admitted in three hospitals of Karachi. One hundred patients of dengue fever with positive anti-dengue Immunoglobulin M (IgM) serology were included in the study. The admitted patients in PNS Shifa Hospital, Jinnah Postgraduate Medical Centre (JPMC) and Civil Hospital, Karachi were selected for the study. Presenting features were noted. The patients were physically examined for the presence of skin and mucosal lesions and findings were recorded. Total and Differential Leukocyte Count (TLC and DLC), platelet count and Liver Function Tests (LFTs) were done in all the patients. All the patients had low leukocyte and low platelet counts. The common presenting symptoms were high-grade fever with or without rigors, headache, body aches, backache, vomiting, sore throat with cough and generalized weakness (seen in 86% patients). The uncommon presenting features were diarrhea, abdominal pain, bleeding from gums and nosebleeds (seen in 14% patients). Sixty-eight (68%) patients had skin lesions. The most common skin presentation was generalized macular blanchable erythema involving trunk and limbs, seen in 44 (65%) cases. Discrete petechial lesions were seen on various body areas in 24 (35%) cases. Palmer erythema was seen in 20 (30%) patients. Generalized itching was seen in 16 (23%) cases. Isolated itching of palms and soles was seen in 20 (30%) cases. Twenty-eight (28%) patients had deranged LFTs. Out of those, 4 patients had raised serum bilirubin level whereas rest of the 24 had raised ALT. Dengue fever commonly presents with specific skin lesions. The skin lesions can be a clue to the diagnosis in difficult cases. (author)

  17. Evaluation of a simple polytetrafluoroethylene (PTFE)-based membrane for blood-feeding of malaria and dengue fever vectors in the laboratory.

    Science.gov (United States)

    Siria, Doreen J; Batista, Elis P A; Opiyo, Mercy A; Melo, Elizangela F; Sumaye, Robert D; Ngowo, Halfan S; Eiras, Alvaro E; Okumu, Fredros O

    2018-04-11

    , where DHF is unfeasible. If improved (e.g. minimizing temperature fluctuations), the approach could possibly also support studies where vectors are artificially infected with blood-borne pathogens.

  18. 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).

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

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    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.

  20. Nation-wide, web-based, geographic information system for the integrated surveillance and control of dengue fever in Mexico.

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    Juan Eugenio Hernández-Ávila

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

  1. Nation-wide, web-based, geographic information system for the integrated surveillance and control of dengue fever in Mexico.

    Science.gov (United States)

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

    2013-01-01

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

  2. 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.

  3. Application of Artificial Neural Networks for Dengue Fever Outbreak Predictions in the Northwest Coast of Yucatan, Mexico and San Juan, Puerto Rico

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    Abdiel E. Laureano-Rosario

    2018-01-01

    Full Text Available Modelling dengue fever in endemic areas is important to mitigate and improve vector-borne disease control to reduce outbreaks. This study applied artificial neural networks (ANNs to predict dengue fever outbreak occurrences in San Juan, Puerto Rico (USA, and in several coastal municipalities of the state of Yucatan, Mexico, based on specific thresholds. The models were trained with 19 years of dengue fever data for Puerto Rico and six years for Mexico. Environmental and demographic data included in the predictive models were sea surface temperature (SST, precipitation, air temperature (i.e., minimum, maximum, and average, humidity, previous dengue cases, and population size. Two models were applied for each study area. One predicted dengue incidence rates based on population at risk (i.e., numbers of people younger than 24 years, and the other on the size of the vulnerable population (i.e., number of people younger than five years and older than 65 years. The predictive power was above 70% for all four model runs. The ANNs were able to successfully model dengue fever outbreak occurrences in both study areas. The variables with the most influence on predicting dengue fever outbreak occurrences for San Juan, Puerto Rico, included population size, previous dengue cases, maximum air temperature, and date. In Yucatan, Mexico, the most important variables were population size, previous dengue cases, minimum air temperature, and date. These models have predictive skills and should help dengue fever mitigation and management to aid specific population segments in the Caribbean region and around the Gulf of Mexico.

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

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    Nucci Luciana B

    2011-05-01

    Full Text Available Abstract 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

  5. Clinical and laboratory features of dengue virus-infected travellers previously vaccinated against yellow fever

    NARCIS (Netherlands)

    Teichmann, Dieter; Göbels, Klaus; Niedrig, Matthias; Grobusch, Martin P.

    2003-01-01

    Dengue is a mosquito-borne viral infection endemic throughout the tropics and subtropics. The global prevalence of dengue has grown dramatically in recent years and it has become a major international public health concern. The close taxonomic relationships between yellow fever and dengue viruses

  6. Bilateral optic neuritis with maculopathy: A rare manifestation of dengue fever

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    Yang Liang Boo

    2017-04-01

    Full Text Available Dengue fever is a common mosquito-borne disease, which is endemic in tropical and subtropical countries. Bilateral optic neuropathy is a relatively unusual dengue-related ocular complication. Here, we present a case of bilateral optic neuritis with maculopathy complicating dengue infection.

  7. Dengue as a cause of fever during pregnancy: a report of two cases

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    Ariani Impieri Souza

    2016-06-01

    Full Text Available Abstract: Dengue infection has not been routinely investigated among pregnant women and parturients with acute febrile syndrome in endemic settings. Here, we report two cases of dengue fever detected at the time of delivery in parturients enrolled in a cohort prospective study conducted in a hospital in Recife, Brazil. The parturients reported fever onset within seven days prior to delivery, and dengue infection was confirmed upon detection of viral ribonucleic acid (RNA by using the reverse transcriptase-polymerase chain reaction. Dengue infection should be considered as a diagnostic possibility in cases of fever during pregnancy and labor, especially in endemic areas.

  8. 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…

  9. 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

    2013-01-01

    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. PMID:24047566

  10. Population density, water supply, and the risk of dengue fever in Vietnam: cohort study and spatial analysis.

    Science.gov (United States)

    Schmidt, Wolf-Peter; Suzuki, Motoi; Thiem, Vu Dinh; White, Richard G; Tsuzuki, Ataru; Yoshida, Lay-Myint; Yanai, Hideki; Haque, Ubydul; Tho, Le Huu; Anh, Dang Duc; Ariyoshi, Koya

    2011-08-01

    Aedes aegypti, the major vector of dengue viruses, often breeds in water storage containers used by households without tap water supply, and occurs in high numbers even in dense urban areas. We analysed the interaction between human population density and lack of tap water as a cause of dengue fever outbreaks with the aim of identifying geographic areas at highest risk. We conducted an individual-level cohort study in a population of 75,000 geo-referenced households in Vietnam over the course of two epidemics, on the basis of dengue hospital admissions (n = 3,013). We applied space-time scan statistics and mathematical models to confirm the findings. We identified a surprisingly narrow range of critical human population densities between around 3,000 to 7,000 people/km² prone to dengue outbreaks. In the study area, this population density was typical of villages and some peri-urban areas. Scan statistics showed that areas with a high population density or adequate water supply did not experience severe outbreaks. The risk of dengue was higher in rural than in urban areas, largely explained by lack of piped water supply, and in human population densities more often falling within the critical range. Mathematical modeling suggests that simple assumptions regarding area-level vector/host ratios may explain the occurrence of outbreaks. Rural areas may contribute at least as much to the dissemination of dengue fever as cities. Improving water supply and vector control in areas with a human population density critical for dengue transmission could increase the efficiency of control efforts. Please see later in the article for the Editors' Summary.

  11. Population density, water supply, and the risk of dengue fever in Vietnam: cohort study and spatial analysis.

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    Wolf-Peter Schmidt

    2011-08-01

    Full Text Available Aedes aegypti, the major vector of dengue viruses, often breeds in water storage containers used by households without tap water supply, and occurs in high numbers even in dense urban areas. We analysed the interaction between human population density and lack of tap water as a cause of dengue fever outbreaks with the aim of identifying geographic areas at highest risk.We conducted an individual-level cohort study in a population of 75,000 geo-referenced households in Vietnam over the course of two epidemics, on the basis of dengue hospital admissions (n = 3,013. We applied space-time scan statistics and mathematical models to confirm the findings. We identified a surprisingly narrow range of critical human population densities between around 3,000 to 7,000 people/km² prone to dengue outbreaks. In the study area, this population density was typical of villages and some peri-urban areas. Scan statistics showed that areas with a high population density or adequate water supply did not experience severe outbreaks. The risk of dengue was higher in rural than in urban areas, largely explained by lack of piped water supply, and in human population densities more often falling within the critical range. Mathematical modeling suggests that simple assumptions regarding area-level vector/host ratios may explain the occurrence of outbreaks.Rural areas may contribute at least as much to the dissemination of dengue fever as cities. Improving water supply and vector control in areas with a human population density critical for dengue transmission could increase the efficiency of control efforts. Please see later in the article for the Editors' Summary.

  12. Dengue in travellers: applicability of the 1975-1997 and the 2009 WHO classification system of dengue fever

    NARCIS (Netherlands)

    Wieten, Rosanne W.; Vlietstra, Wytze; Goorhuis, Abraham; van Vugt, Michèle; Hodiamont, Caspar J.; Leenstra, Tjalling; de Vries, Peter J.; Janssen, Saskia; van Thiel, Pieter P.; Stijnis, Kees; Grobusch, Martin P.

    2012-01-01

    Objectives The aim of this study was to assess the applicability and benefits of the new WHO dengue fever guidelines in clinical practice, for returning travellers. Methods We compared differences in specificity and sensitivity between the old and the new guidelines for diagnosing dengue and

  13. 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.

  14. Retinoids, race and the pathogenesis of dengue hemorrhagic fever.

    Science.gov (United States)

    Mawson, Anthony R

    2013-12-01

    Dengue hemorrhagic fever (DHF) is the most significant mosquito-borne viral disease worldwide in terms of illness, mortality and economic cost, but the pathogenesis of DHF is not well understood and there is no specific treatment or vaccine. Based on evidence of liver involvement, it is proposed that dengue virus and retinoids interact to cause cholestatic liver damage, resulting in the spillage of stored retinoids into the circulation and in an endogenous form of hypervitaminosisis A manifested by the signs and symptoms of the disease, including: fever, severe joint and bone pain, capillary leakage, thrombocytopenia, headache, and gastrointestinal symptoms. While retinoids in low concentration are essential for numerous biological functions, they are prooxidant, cytotoxic, mutagenic and teratogenic in higher concentration, especially when unbound to protein, and an endogenous form of vitamin A intoxication is recognized in cholestasis. The model tentatively explains the observations that 1) repeat infections are more severe than initial dengue virus infections; 2) the incidence of denue has increased dramatically worldwide in recent decades; 3) DHF is less prevalent in people of African ancestry than those of other racial backgrounds; and 4) infants are protected from dengue. The retinoid toxicity hypothesis of DHF predicts the co-existence of low serum concentrations of retinol coupled with high concentrations of retinoic acid and an increased percentage of retinyl esters to total vitamin A. Subject to such tests, it may be possible to treat DHF effectively using drugs that target the metabolism and expression of retinoids. Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.

  15. Estudo comparativo de eficácia de larvitrampas e ovitrampas para vigilância de vetores de dengue e febre amarela Comparative study of the efficiency of larval and ovitraps for the surveillance of dengue and yellow fever vectors

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    Cristiano Correa de Azevedo Marques

    1993-08-01

    Full Text Available Com a finalidade de aprimorar a vigilância entomológica dos vetores de Dengue e Febre Amarela - Aedes aegypti e Aedes albopictus - no Estado de São Paulo, Brasil, realizou-se estudo comparativo de eficácia de larvitrampas (armadilhas de larvas, e ovitrampas (armadilhas de ovos. A região estudada é infestada somente pelo Aedes albopictus, espécie que conserva hábitos silvestres, mas também coloniza criadouros artificiais. A primeira parte do estudo foi realizada em área periurbana de Tremembé-SP, onde foram comparados três ocos de árvore, 23 ovitrampas e 5 larvitrampas. A segunda parte dos experimentos desenvolveu-se no Município de Lavrinhas-SP, no distrito de Pinheiros, onde 20 ovitrampas foram instaladas (uma por quadra e 5 larvitrampas foram localizadas em pontos estratégicos (comércios, depósitos e postos. Os resultados obtidos mostraram que a ovitrampa, além da capacidade de positivar-se mesmo em presença de criadouros naturais, possui eficiência superior à larvitrampa. Constatou-se que para avaliação de efeitos da termonebulização as ovitrampas apresentaram uma significativa redução na média de ovos, o que não se verificou em relação ao Índice de Breteau.A comparative study of the efficiency of ovitraps and larval-traps was undertaken with a view to improving the entomological survey of vectors of Dengue and Yellow Fever - Aedes aegypti and Aedes albopictus - in S. Paulo State, Brazil. The region studied is infested only by Aedes albopictus, a species that keeps to wild habitats but colonizes artificial breeding grounds as well. The first part of the study was located in a periurban area of Tremembé county were 3 hollon trees, 23 ovitraps and 5 larval-traps were compared. The second part of these experiments took place in Lavrinhas county (Pinheiros district, where 20 ovitraps and 5 larval-traps were tested. The results showed that the ovitrap was more efficiente than larval-traps and were positive even in

  16. P. vivax malaria and dengue fever co-infection: a cross-sectional study in the Brazilian Amazon.

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    Belisa M L Magalhães

    2014-10-01

    Full Text Available Malaria and dengue are the most prevalent vector-borne diseases worldwide and represent major public health problems. Both are endemic in tropical regions, propitiating co-infection. Only few co-infection cases have been reported around the world, with insufficient data so far to enhance the understanding of the effects of co-infection in the clinical presentation and severity.A cross-sectional study was conducted (2009 to 2011 in hospitalized patients with acute febrile syndrome in the Brazilian Amazon. All patients were submitted to thick blood smear and PCR for Plasmodium sp. detection, ELISA, PCR and NS1 tests for dengue, viral hepatitis, HIV and leptospirosis. In total, 1,578 patients were recruited. Among them, 176 (11.1% presented P. vivax malaria mono-infection, 584 (37% dengue fever mono-infection, and 44 (2.8% were co-infected. Co-infected patients had a higher chance of presenting severe disease (vs. dengue mono-infected, deep bleeding (vs. P. vivax mono-infected, hepatomegaly, and jaundice (vs. dengue mono-infected.In endemic areas for dengue and malaria, jaundice (in dengue patients and spontaneous bleeding (in malaria patients should raise the suspicion of co-infection. Besides, whenever co-infection is confirmed, we recommend careful monitoring for bleeding and hepatic complications, which may result in a higher chance of severity, despite of the fact that no increased fatality rate was seen in this group.

  17. P. vivax Malaria and Dengue Fever Co-infection: A Cross-Sectional Study in the Brazilian Amazon

    Science.gov (United States)

    Magalhães, Belisa M. L.; Siqueira, André M.; Alexandre, Márcia A. A.; Souza, Marcela S.; Gimaque, João B.; Bastos, Michele S.; Figueiredo, Regina M. P.; Melo, Gisely C.; Lacerda, Marcus V. G.; Mourão, Maria P. G.

    2014-01-01

    Background Malaria and dengue are the most prevalent vector-borne diseases worldwide and represent major public health problems. Both are endemic in tropical regions, propitiating co-infection. Only few co-infection cases have been reported around the world, with insufficient data so far to enhance the understanding of the effects of co-infection in the clinical presentation and severity. Methodology/Principal Findings A cross-sectional study was conducted (2009 to 2011) in hospitalized patients with acute febrile syndrome in the Brazilian Amazon. All patients were submitted to thick blood smear and PCR for Plasmodium sp. detection, ELISA, PCR and NS1 tests for dengue, viral hepatitis, HIV and leptospirosis. In total, 1,578 patients were recruited. Among them, 176 (11.1%) presented P. vivax malaria mono-infection, 584 (37%) dengue fever mono-infection, and 44 (2.8%) were co-infected. Co-infected patients had a higher chance of presenting severe disease (vs. dengue mono-infected), deep bleeding (vs. P. vivax mono-infected), hepatomegaly, and jaundice (vs. dengue mono-infected). Conclusions/Significance In endemic areas for dengue and malaria, jaundice (in dengue patients) and spontaneous bleeding (in malaria patients) should raise the suspicion of co-infection. Besides, whenever co-infection is confirmed, we recommend careful monitoring for bleeding and hepatic complications, which may result in a higher chance of severity, despite of the fact that no increased fatality rate was seen in this group. PMID:25340346

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

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    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.

  19. An economic evaluation of vector control in the age of a dengue vaccine.

    Science.gov (United States)

    Fitzpatrick, Christopher; Haines, Alexander; Bangert, Mathieu; Farlow, Andrew; Hemingway, Janet; Velayudhan, Raman

    2017-08-01

    Dengue is a rapidly emerging vector-borne Neglected Tropical Disease, with a 30-fold increase in the number of cases reported since 1960. The economic cost of the illness is measured in the billions of dollars annually. Environmental change and unplanned urbanization are conspiring to raise the health and economic cost even further beyond the reach of health systems and households. The health-sector response has depended in large part on control of the Aedes aegypti and Ae. albopictus (mosquito) vectors. The cost-effectiveness of the first-ever dengue vaccine remains to be evaluated in the field. In this paper, we examine how it might affect the cost-effectiveness of sustained vector control. We employ a dynamic Markov model of the effects of vector control on dengue in both vectors and humans over a 15-year period, in six countries: Brazil, Columbia, Malaysia, Mexico, the Philippines, and Thailand. We evaluate the cost (direct medical costs and control programme costs) and cost-effectiveness of sustained vector control, outbreak response and/or medical case management, in the presence of a (hypothetical) highly targeted and low cost immunization strategy using a (non-hypothetical) medium-efficacy vaccine. Sustained vector control using existing technologies would cost little more than outbreak response, given the associated costs of medical case management. If sustained use of existing or upcoming technologies (of similar price) reduce vector populations by 70-90%, the cost per disability-adjusted life year averted is 2013 US$ 679-1331 (best estimates) relative to no intervention. Sustained vector control could be highly cost-effective even with less effective technologies (50-70% reduction in vector populations) and in the presence of a highly targeted and low cost immunization strategy using a medium-efficacy vaccine. Economic evaluation of the first-ever dengue vaccine is ongoing. However, even under very optimistic assumptions about a highly targeted and low

  20. An economic evaluation of vector control in the age of a dengue vaccine.

    Directory of Open Access Journals (Sweden)

    Christopher Fitzpatrick

    2017-08-01

    Full Text Available Dengue is a rapidly emerging vector-borne Neglected Tropical Disease, with a 30-fold increase in the number of cases reported since 1960. The economic cost of the illness is measured in the billions of dollars annually. Environmental change and unplanned urbanization are conspiring to raise the health and economic cost even further beyond the reach of health systems and households. The health-sector response has depended in large part on control of the Aedes aegypti and Ae. albopictus (mosquito vectors. The cost-effectiveness of the first-ever dengue vaccine remains to be evaluated in the field. In this paper, we examine how it might affect the cost-effectiveness of sustained vector control.We employ a dynamic Markov model of the effects of vector control on dengue in both vectors and humans over a 15-year period, in six countries: Brazil, Columbia, Malaysia, Mexico, the Philippines, and Thailand. We evaluate the cost (direct medical costs and control programme costs and cost-effectiveness of sustained vector control, outbreak response and/or medical case management, in the presence of a (hypothetical highly targeted and low cost immunization strategy using a (non-hypothetical medium-efficacy vaccine.Sustained vector control using existing technologies would cost little more than outbreak response, given the associated costs of medical case management. If sustained use of existing or upcoming technologies (of similar price reduce vector populations by 70-90%, the cost per disability-adjusted life year averted is 2013 US$ 679-1331 (best estimates relative to no intervention. Sustained vector control could be highly cost-effective even with less effective technologies (50-70% reduction in vector populations and in the presence of a highly targeted and low cost immunization strategy using a medium-efficacy vaccine.Economic evaluation of the first-ever dengue vaccine is ongoing. However, even under very optimistic assumptions about a highly targeted

  1. Spatial evaluation and modeling of Dengue seroprevalence and vector density in Rio de Janeiro, Brazil.

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    Nildimar Alves Honório

    2009-11-01

    Full Text Available Rio de Janeiro, Brazil, experienced a severe dengue fever epidemic in 2008. This was the worst epidemic ever, characterized by a sharp increase in case-fatality rate, mainly among younger individuals. A combination of factors, such as climate, mosquito abundance, buildup of the susceptible population, or viral evolution, could explain the severity of this epidemic. The main objective of this study is to model the spatial patterns of dengue seroprevalence in three neighborhoods with different socioeconomic profiles in Rio de Janeiro. As blood sampling coincided with the peak of dengue transmission, we were also able to identify recent dengue infections and visually relate them to Aedes aegypti spatial distribution abundance. We analyzed individual and spatial factors associated with seroprevalence using Generalized Additive Model (GAM.Three neighborhoods were investigated: a central urban neighborhood, and two isolated areas characterized as a slum and a suburban area. Weekly mosquito collections started in September 2006 and continued until March 2008. In each study area, 40 adult traps and 40 egg traps were installed in a random sample of premises, and two infestation indexes calculated: mean adult density and mean egg density. Sera from individuals living in the three neighborhoods were collected before the 2008 epidemic (July through November 2007 and during the epidemic (February through April 2008. Sera were tested for DENV-reactive IgM, IgG, Nested RT-PCR, and Real Time RT-PCR. From the before-after epidemics paired data, we described seroprevalence, recent dengue infections (asymptomatic or not, and seroconversion. Recent dengue infection varied from 1.3% to 14.1% among study areas. The highest IgM seropositivity occurred in the slum, where mosquito abundance was the lowest, but household conditions were the best for promoting contact between hosts and vectors. By fitting spatial GAM we found dengue seroprevalence hotspots located at the

  2. 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 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.

  3. Isolated unilateral sixth cranial nerve palsy: A rare presentation of dengue fever

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    Yang Liang Boo

    2016-11-01

    Full Text Available Dengue fever is a common mosquito-borne viral infection endemic in tropical and subtropical countries. Neurological manifestations in dengue infection are relatively uncommon, and include encephalitis, encephalopathy, neuromuscular disorders and neuro-ocular disorders. Cranial mononeuropathy is a rare manifestation of dengue infection. A 40-year-old man was diagnosed with isolated, unilateral sixth cranial nerve palsy complicating dengue infection. The patient was managed accordingly, and full ocular recovery was observed. This was the first reported case of isolated sixth cranial nerve palsy associated with dengue fever in Malaysia. It is important for clinicians to consider dengue as a differential diagnosis in patients presenting with fever and sixth cranial nerve palsy.

  4. Successful allogeneic stem cells transplantation in severe aplastic anaemia complicated by dengue fever

    International Nuclear Information System (INIS)

    Ullah, K.; Satti, T.M.; Ahmed, P.; Raza, A.; Akhtar, F.M.; Tariq, W.U.Z.

    2007-01-01

    Aplastic anaemia is characterized by severe compromise of haematopoiesis and hypocellular bone marrow. Haemorrhagic episodes in patients with aplastic anemia occur usually secondary to thrombocytopenia and require frequent support with platelet concentrates and other blood products. Infection with dengue virus (particularly dengue sero type-2 of South Asian genotype) is associated with dengue haemorrhagic fever. Dengue infection further worsens the disease process in patients with aplastic anaemia due to uncontrolled haemorrhagic diathesis and major organ failure, which may prove fatal in these already immunocompromised patients, if not treated in time. Recent epidemics of dengue haemorrhagic fever has not only affected the southern region of our country but also spread to other areas of the country. With this background, we report a case of aplastic anaemia complicated by dengue haemorrhagic fever who achieved successful engraftment after allogeneic stem cell transplantation from sibling brother and is having normal healthy post transplant life. (author)

  5. 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.

  6. Demographic and clinico-epidemiological features of dengue fever in Faisalabad, Pakistan.

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    Faiz Ahmed Raza

    Full Text Available 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 (p<0.001. Abdominal pain was seen in 35% DHF patients followed by nausea in 28.3%, epistaxis in 25% and rash in 20% patients (p<0.05. Patients reported to be suffering from high-grade fever for an average of 8.83 days in DHF as compared to 5.82 days in DF before being hospitalized. Co-morbidities were found to be risk factor for the development of DHF in dengue patients. Clinical and laboratory features of dengue cases studied could be used for the early identification of patients at risk of severe dengue fever.

  7. Application of Gis in Temporal and Spatial Analyses of Dengue Fever Outbreak : Case of Rio de Janeiro, Brazil

    OpenAIRE

    Achu, Denis

    2009-01-01

    Since Dengue fever (DF) and its related forms, Dengue Hemorrhagic fever (DHF) and Dengue Shock Syndrome (DSS) have become important health concerns worldwide, it is also imperative to develop methods which will help in the analysis of the incidences. Dengue fever cases are growing in number as it also invades widely, affecting larger number of countries and crossing climatic boundaries. Considering that the disease as of now has neither an effective vaccine nor a cure, monitoring in order to ...

  8. 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. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. 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.

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

    International Nuclear Information System (INIS)

    Munir, M. A.; Saqib, M. A. N.; Qureshi, H.; Alam, S. E.; Arif, A.; Khan, Z. U.; Saeed, Q.; Iqbal, R.

    2014-01-01

    Objectives: To assess the gaps in the diagnosis and management of dengue fever cases. Methods: 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. Results: 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%). Conclusions: 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. (author)

  11. Hypocholesterolemia as a predictor of disease severity in dengue fever

    International Nuclear Information System (INIS)

    Lodhi, S.; Tahira, Q.A.

    2014-01-01

    Objectives: The objective of this study was to determine the difference between total cholesterol (TC) of dengue fever (DF) and dengue hemorrhagic fever (DHF) patients and also between DHF patients with favourable (DHF I and II) and adverse (DHF III and IV) outcome. Methodology: This comparative cross - sectional study was conducted in the Department of Medicine, Mayo Hospital, Lahore, from August to November 2012. The study comprised of 100 febrile patients with positive dengue serology. TC was measured on the admission day. The patients were observed during admission period for clinical outcome i.e. DF and DHF. DHF patients were graded as I - IV and grouped as favourable (I and II) and adverse (III and IV) out- come. Results: Out of 100 patients included in the study, 64 were males and 36 were females with mean age 33.03 ± 14.5 years and mean TC 3.02 ± 0.88 mmollL. The 63 DF and 37 DHF patients had mean ages of 30.21 ± 12.7 and 37.84 ± 16.2lyears respectively (p-value 0.017) and mean TC 3.43 +- 0.79 and 2.34 ± 0.56 mmollL respectively (p-value 0.000). M:F for DF and DHF was 2:1 and 1.47:1 respectively (p-value 0.001). Among 37 DHF patients, there were 16 DHF I, 8 DHF II, 10 DHF III and 3 DHF IV patients. For DHF I - IV, mean TC was 2.77 ± 0.45, 2.16 ± 0.33, 2.05 ± 0.35 and 1.49 ± 0.35 mmollL respectively. DHF patients with favourable and adverse out.come had mean TC 2.55 ± 0.5 and 1.92 ± 0.42 mmolll respectively (p = value 0.000). Conclusion: Low serum TC strongly correlated with disease severity in dengue fever patients. (author)

  12. Management of symptomatic thrombocytopenia associated with dengue haemorrhagic fever

    International Nuclear Information System (INIS)

    Jameel, T.; Saleem, I.U.; Mehmood, K.; Tanvir, I.; Saadia, A.

    2010-01-01

    Introduction: Immune - mediated destruction of platelets is thought to be the mechanism of thrombocytopenia seen after the viraemic phase of dengue haemorrhagic fever (DHF). Immuno - suppressants such as steroids, immune globulin and Anti D immune globulin are effective in the treatment of this type of immune thrombocytopenic purpura. Objective: To evaluate the efficacy of oral Prednisolone in the rate of resolution of thrombocytopenia and monitoring of complications in patients recovering from Dengue haemorrhagic fever. Method: A controlled study was carried out on diagnosed cases Dengue haemorrhagic patients presenting with sever thrombocytopenia and symptoms like confluent ecchymosis, epistaxis and purpuric rashes. In study was conducted in Ittefaq hospital (trust) Lahore, during the period of October to December 2008. Treatment group received steroids in two forms i.e. first line therapy prednisolone (1 mg / kg) orally or as second line therapy of initial I/V high dose (prednisolone) in pulse doses i.e. 40 mg / bd for four days and later oral prednisolone as in first line therapy with omeprazole 20 mg / bd in addition to standard treatment. Control group received standard supportive care only. Results: A total of 341 suspected patients were admitted in hospital. Serological diagnosis was confirmed in 166 patients. CBC revealed platelet count . 100 x 109 / l in 106 patients. A group of symptomatic febrile patients have platelet count < 20 x 109 / l was selected for therapeutic intervention. first line therapy (oral prednisolone was stated in 43 patients. In Fourteen patients second line therapy (high dose dexamethasone pulse) therapy was instituted. Seven of them attained complete response whereas two patients achieved partial response. Four patients were shifted to Anti D therapy. Three deaths occurred during our study. Rest of all the patients improved and were discharged in due course of time. Conclusion: This small scale preliminary study shows promising

  13. Assessment of Dengue Fever Severity Through Liver Function Tests

    International Nuclear Information System (INIS)

    Ahmed, A.; Alvi, A. H.; Nawaz, A. A.; Butt, A.; Hanif, A.

    2014-01-01

    Objective: To assess the utility of liver function tests (LFTs) for early recognition and prediction of severity of Dengue fever in hospitalized patients. Study Design: An analytical study. Place and Duration of Study: Services Institute of Medical Science and Fatima Memorial Hospital, Lahore, from September - December 2010. Methodology: Admitted cases of Dengue fever were divided into 3 groups; mild, moderate and severe increases in aminotransferases. Elevation in LFTs was co-related with good or bad outcome i.e. (survival or complication free stay) or (death or complications). Results were analyzed in SPSS version 18. Results: Out of the 353 patients with mean age of 37.12 +- 15.45 years, 245 (69.4%) were males and 108 (30.6%) were females. Seventy five patients (21.2%) had mild elevation of aminotransferases (2 fold increases), 265 patients (75.1%) had moderate increases (3 to 4 fold) and 13 (3.7%) had severe (> 4 fold increase). ALT was statistically higher in patients with septicemia, hepatic and renal failure (p-value 0.05). AST was higher in almost all complications. Prolonged hospital stay was associated with raised LFTs and greater complications and mortality. AST was found to be twice as much raised as ALT. Conclusion: AST and ALT were statistically higher in patients with worse outcome thus can lead to early recognition of high risk cases. (author)

  14. Lie integrable cases of the simplified multistrain/two-stream model for tuberculosis and dengue fever

    Science.gov (United States)

    Nucci, M. C.; Leach, P. G. L.

    2007-09-01

    We apply the techniques of Lie's symmetry analysis to a caricature of the simplified multistrain model of Castillo-Chavez and Feng [C. Castillo-Chavez, Z. Feng, To treat or not to treat: The case of tuberculosis, J. Math. Biol. 35 (1997) 629-656] for the transmission of tuberculosis and the coupled two-stream vector-based model of Feng and Velasco-Hernandez [Z. Feng, J.X. Velasco-Hernandez, Competitive exclusion in a vector-host model for the dengue fever, J. Math. Biol. 35 (1997) 523-544] to identify the combinations of parameters which lead to the existence of nontrivial symmetries. In particular we identify those combinations which lead to the possibility of the linearization of the system and provide the corresponding solutions. Many instances of additional symmetry are analyzed.

  15. A critical assessment of vector control for dengue prevention.

    Directory of Open Access Journals (Sweden)

    Nicole L Achee

    2015-05-01

    Full Text Available Recently, the Vaccines to Vaccinate (v2V initiative was reconfigured into the Partnership for Dengue Control (PDC, a multi-sponsored and independent initiative. This redirection is consistent with the growing consensus among the dengue-prevention community that no single intervention will be sufficient to control dengue disease. The PDC's expectation is that when an effective dengue virus (DENV vaccine is commercially available, the public health community will continue to rely on vector control because the two strategies complement and enhance one another. Although the concept of integrated intervention for dengue prevention is gaining increasingly broader acceptance, to date, no consensus has been reached regarding the details of how and what combination of approaches can be most effectively implemented to manage disease. To fill that gap, the PDC proposed a three step process: (1 a critical assessment of current vector control tools and those under development, (2 outlining a research agenda for determining, in a definitive way, what existing tools work best, and (3 determining how to combine the best vector control options, which have systematically been defined in this process, with DENV vaccines. To address the first step, the PDC convened a meeting of international experts during November 2013 in Washington, DC, to critically assess existing vector control interventions and tools under development. This report summarizes those deliberations.

  16. El Nino Southern Oscillation and vegetation dynamics as predictors of dengue fever cases in Costa Rica

    International Nuclear Information System (INIS)

    Fuller, D O; Troyo, A; Beier, J C

    2009-01-01

    Dengue fever (DF) and dengue hemorrhagic fever (DHF) are growing health concerns throughout Latin America and the Caribbean. This study focuses on Costa Rica, which experienced over 100 000 cases of DF/DHF from 2003 to 2007. We utilized data on sea-surface temperature anomalies related to the El Nino Southern Oscillation (ENSO) and two vegetation indices derived from the Moderate Resolution Imaging Spectrometer (MODIS) from the Terra satellite to model the influence of climate and vegetation dynamics on DF/DHF cases in Costa Rica. Cross-correlations were calculated to evaluate both positive and negative lag effects on the relationships between independent variables and DF/DHF cases. The model, which utilizes a sinusoid and non-linear least squares to fit case data, was able to explain 83% of the variance in weekly DF/DHF cases when independent variables were shifted backwards in time. When the independent variables were shifted forward in time, consistently with a forecasting approach, the model explained 64% of the variance. Importantly, when five ENSO and two vegetation indices were included, the model reproduced a major DF/DHF epidemic of 2005. The unexplained variance in the model may be due to herd immunity and vector control measures, although information regarding these aspects of the disease system are generally lacking. Our analysis suggests that the model may be used to predict DF/DHF outbreaks as early as 40 weeks in advance and may also provide valuable information on the magnitude of future epidemics. In its current form it may be used to inform national vector control programs and policies regarding control measures; it is the first climate-based dengue model developed for this country and is potentially scalable to the broader region of Latin America and the Caribbean where dramatic increases in DF/DHF incidence and spread have been observed.

  17. El Nino Southern Oscillation and vegetation dynamics as predictors of dengue fever cases in Costa Rica

    Energy Technology Data Exchange (ETDEWEB)

    Fuller, D O [Department of Geography and Regional Studies, University of Miami, Coral Gables, FL 33124-2221 (United States); Troyo, A [Centro de Investigacion en Enfermedades Tropicales, Departamento de ParasitologIa, Facultad de MicrobiologIa, Universidad de Costa Rica, San Jose (Costa Rica); Beier, J C [Global Public Health Program, Department of Epidemiology and Public Health, University of Miami, Miami, FL (United States)], E-mail: dofuller@miami.edu

    2009-01-15

    Dengue fever (DF) and dengue hemorrhagic fever (DHF) are growing health concerns throughout Latin America and the Caribbean. This study focuses on Costa Rica, which experienced over 100 000 cases of DF/DHF from 2003 to 2007. We utilized data on sea-surface temperature anomalies related to the El Nino Southern Oscillation (ENSO) and two vegetation indices derived from the Moderate Resolution Imaging Spectrometer (MODIS) from the Terra satellite to model the influence of climate and vegetation dynamics on DF/DHF cases in Costa Rica. Cross-correlations were calculated to evaluate both positive and negative lag effects on the relationships between independent variables and DF/DHF cases. The model, which utilizes a sinusoid and non-linear least squares to fit case data, was able to explain 83% of the variance in weekly DF/DHF cases when independent variables were shifted backwards in time. When the independent variables were shifted forward in time, consistently with a forecasting approach, the model explained 64% of the variance. Importantly, when five ENSO and two vegetation indices were included, the model reproduced a major DF/DHF epidemic of 2005. The unexplained variance in the model may be due to herd immunity and vector control measures, although information regarding these aspects of the disease system are generally lacking. Our analysis suggests that the model may be used to predict DF/DHF outbreaks as early as 40 weeks in advance and may also provide valuable information on the magnitude of future epidemics. In its current form it may be used to inform national vector control programs and policies regarding control measures; it is the first climate-based dengue model developed for this country and is potentially scalable to the broader region of Latin America and the Caribbean where dramatic increases in DF/DHF incidence and spread have been observed.

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

    Directory of Open Access Journals (Sweden)

    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.

  19. Multiple introductions of the dengue vector, Aedes aegypti, into California.

    Science.gov (United States)

    Pless, Evlyn; Gloria-Soria, Andrea; Evans, Benjamin R; Kramer, Vicki; Bolling, Bethany G; Tabachnick, Walter J; Powell, Jeffrey R

    2017-08-01

    The yellow fever mosquito Aedes aegypti inhabits much of the tropical and subtropical world and is a primary vector of dengue, Zika, and chikungunya viruses. Breeding populations of A. aegypti were first reported in California (CA) in 2013. Initial genetic analyses using 12 microsatellites on collections from Northern CA in 2013 indicated the South Central US region as the likely source of the introduction. We expanded genetic analyses of CA A. aegypti by: (a) examining additional Northern CA samples and including samples from Southern CA, (b) including more southern US populations for comparison, and (c) genotyping a subset of samples at 15,698 SNPs. Major results are: (1) Northern and Southern CA populations are distinct. (2) Northern populations are more genetically diverse than Southern CA populations. (3) Northern and Southern CA groups were likely founded by two independent introductions which came from the South Central US and Southwest US/northern Mexico regions respectively. (4) Our genetic data suggest that the founding events giving rise to the Northern CA and Southern CA populations likely occurred before the populations were first recognized in 2013 and 2014, respectively. (5) A Northern CA population analyzed at multiple time-points (two years apart) is genetically stable, consistent with permanent in situ breeding. These results expand previous work on the origin of California A. aegypti with the novel finding that this species entered California on multiple occasions, likely some years before its initial detection. This work has implications for mosquito surveillance and vector control activities not only in California but also in other regions where the distribution of this invasive mosquito is expanding.

  20. Multiple introductions of the dengue vector, Aedes aegypti, into California.

    Directory of Open Access Journals (Sweden)

    Evlyn Pless

    2017-08-01

    Full Text Available The yellow fever mosquito Aedes aegypti inhabits much of the tropical and subtropical world and is a primary vector of dengue, Zika, and chikungunya viruses. Breeding populations of A. aegypti were first reported in California (CA in 2013. Initial genetic analyses using 12 microsatellites on collections from Northern CA in 2013 indicated the South Central US region as the likely source of the introduction. We expanded genetic analyses of CA A. aegypti by: (a examining additional Northern CA samples and including samples from Southern CA, (b including more southern US populations for comparison, and (c genotyping a subset of samples at 15,698 SNPs. Major results are: (1 Northern and Southern CA populations are distinct. (2 Northern populations are more genetically diverse than Southern CA populations. (3 Northern and Southern CA groups were likely founded by two independent introductions which came from the South Central US and Southwest US/northern Mexico regions respectively. (4 Our genetic data suggest that the founding events giving rise to the Northern CA and Southern CA populations likely occurred before the populations were first recognized in 2013 and 2014, respectively. (5 A Northern CA population analyzed at multiple time-points (two years apart is genetically stable, consistent with permanent in situ breeding. These results expand previous work on the origin of California A. aegypti with the novel finding that this species entered California on multiple occasions, likely some years before its initial detection. This work has implications for mosquito surveillance and vector control activities not only in California but also in other regions where the distribution of this invasive mosquito is expanding.

  1. 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.

  2. 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

    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. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  3. 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

    2017-10-01

    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.

  4. 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.

  5. Humoral immune responses of dengue fever patients using epitope-specific serotype-2 virus-like particle antigens.

    Directory of Open Access Journals (Sweden)

    Wayne D Crill

    Full Text Available Dengue virus (DENV is a serious mosquito-borne pathogen causing significant global disease burden, either as classic dengue fever (DF or in its most severe manifestation dengue hemorrhagic fever (DHF. Nearly half of the world's population is at risk of dengue disease and there are estimated to be millions of infections annually; a situation which will continue to worsen with increasing expansion of the mosquito vectors and epidemic DF/DHF. Currently there are no available licensed vaccines or antivirals for dengue, although significant effort has been directed toward the development of safe and efficacious dengue vaccines for over 30 years. Promising vaccine candidates are in development and testing phases, but a better understanding of immune responses to DENV infection and vaccination is needed. Humoral immune responses to DENV infection are complex and may exacerbate pathogenicity, yet are essential for immune protection. In this report, we develop DENV-2 envelope (E protein epitope-specific antigens and measure immunoglobulin responses to three distinct epitopes in DENV-2 infected human serum samples. Immunoglobulin responses to DENV-2 infection exhibited significant levels of individual variation. Antibody populations targeting broadly cross-reactive epitopes centered on the fusion peptide in structural domain II were large, highly variable, and greater in primary than in secondary DENV-2 infected sera. E protein domain III cross-reactive immunoglobulin populations were similarly variable and much larger in IgM than in IgG. DENV-2 specific domain III IgG formed a very small proportion of the antibody response yet was significantly correlated with DENV-2 neutralization, suggesting that the highly protective IgG recognizing this epitope in murine studies plays a role in humans as well. This report begins to tease apart complex humoral immune responses to DENV infection and is thus important for improving our understanding of dengue disease

  6. Yellow fever vectors' surveillance in three satellite communities of ...

    African Journals Online (AJOL)

    Outbreaks of yellow fever have continued to occur in various parts of Nigeria. ... easily render themselves to vector and environmental management strategies. ... vectors, while locally adapted CDC (Centre for Disease Control) ovitraps were ...

  7. Community effectiveness of copepods for dengue vector control: systematic review.

    Science.gov (United States)

    Lazaro, A; Han, W W; Manrique-Saide, P; George, L; Velayudhan, R; Toledo, J; Runge Ranzinger, S; Horstick, O

    2015-06-01

    Vector control remains the only available method for primary prevention of dengue. Several interventions exist for dengue vector control, with limited evidence of their efficacy and community effectiveness. This systematic review compiles and analyses the existing global evidence for community effectiveness of copepods for dengue vector control. The systematic review follows the PRISMA statement, searching six relevant databases. Applying all inclusion and exclusion criteria, 11 articles were included. There is evidence that cyclopoid copepods (Mesocyclops spp.) could potentially be an effective vector control option, as shown in five community effectiveness studies in Vietnam. This includes long-term effectiveness for larval and adult control of Ae. aegypti, as well as dengue incidence. However, this success has so far not been replicated elsewhere (six studies, three community effectiveness studies--Costa Rica, Mexico and USA, and three studies analysing both efficacy and community effectiveness--Honduras, Laos and USA), probably due to community participation, environmental and/or biological factors. Judging by the quality of existing studies, there is a lack of good study design, data quality and appropriate statistics. There is limited evidence for the use of cyclopoid copepods as a single intervention. There are very few studies, and more are needed in other communities and environments. Clear best practice guidelines for the methodology of entomological studies should be developed. © 2015 John Wiley & Sons Ltd.

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

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    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.

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

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    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.

  10. Role of Ultrasonography in Diagnosis and Evaluation of Dengue Fever

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    Harshavardhan Nagolu

    2017-10-01

    Full Text Available Introduction: Dengue Fever (DF is endemic to Southeast Asian region and poses a major public health problem with increasing incidence of epidemics over the past few years. Aim: This study intends to evaluate ultrasonographic findings in patients with DF during an epidemic in south India and their accuracy in diagnosis. Materials and Methods: This is a prospective observational study performed in tertiary care hospital in Tirupati, Andhra Pradesh, India. A total 310 patients seropositive for dengue, referred to Radiology department for sonography were screened for ascites, gall bladder wall thickening, pleural effusion, pericardial effusion, hepatomegaly and splenomegaly. These findings were correlated with patient demographics, serological tests for dengue and platelet count. Results: Mean age of the study population was 48.9 years. The male: female ratio was 1.46:1. Total 302 patients (97.4% had at least one positive ultrasound finding supportive of DF. Ascites (93% was the most common finding, followed by right pleural effusion (78.7%, gall bladder wall thickening (64.8%, left and bilateral pleural effusion (64.1%, splenomegaly (42.6% and hepatomegaly (28.0%. Patients were classified into four groups based on degree of thrombocytopenia. Ascites was the most common finding in all the groups of patients. Gall bladder wall thickening was seen in 63.2%, 70.5%, 73.0% and 27.7% in four groups respectively. Ascites was the most sensitive finding, while gall bladder wall thickening was the most specific finding. This study showed statistically significant correlation of ultrasound findings with platelet counts (p=0.00001. No statistically significant correlation was noted between age group of the patients and sonographic findings (p=0.908. Conclusion: Constellation of sonographic findings like ascites, gall bladder wall thickening, pleural effusion, hepatomegaly and splenomegaly, when used together, are Useful not only in early diagnosis of the

  11. Clinico-laboratory spectrum of dengue viral infection and risk factors associated with dengue hemorrhagic fever: a retrospective study.

    Science.gov (United States)

    Mallhi, Tauqeer Hussain; Khan, Amer Hayat; Adnan, Azreen Syazril; Sarriff, Azmi; Khan, Yusra Habib; Jummaat, Fauziah

    2015-09-30

    The incidence of dengue is rising steadily in Malaysia since the first major outbreak in 1973. Despite aggressive measures taken by the relevant authorities, Malaysia is still facing worsening dengue crisis over the past few years. There is an urgent need to evaluate dengue cases for better understanding of clinic-laboratory spectrum in order to combat this disease. A retrospective analysis of dengue patients admitted to a tertiary care teaching hospital during the period of six years (2008 - 2013) was performed. Patient's demographics, clinical and laboratory findings were recorded via structured data collection form. Patients were categorized into dengue fever (DF) and dengue hemorrhagic fever (DHF). Appropriate statistical methods were used to compare these two groups in order to determine difference in clinico-laboratory characteristics and to identify independent risk factors of DHF. A total 667 dengue patients (30.69 ± 16.13 years; Male: 56.7 %) were reviewed. Typical manifestations of dengue like fever, myalgia, arthralgia, headache, vomiting, abdominal pain and skin rash were observed in more than 40 % patients. DHF was observed in 79 (11.8 %) cases. Skin rash, dehydration, shortness of breath, pleural effusion and thick gall bladder were more significantly (P  40 years (OR: 4.1, P hospitalization (OR: 2.3, P = 0.037) as independent predictors of DHF. Overall mortality was 1.2 % in our study. Current study demonstrated that DF and DHF present significantly different clinico-laboratory profile. Older age, secondary infection, diabetes mellitus, lethargy, thick gallbladder and delayed hospitalization significantly predict DHF. Prior knowledge of expected clinical profile and predictors of DHF/DSS development would provide information to identify individuals at higher risk and on the other hand, give sufficient time to clinicians for reducing dengue related morbidity and mortality.

  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. 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

  14. Prevalence of undifferentiated fever in adults of Rawalpindi having primary dengue fever

    International Nuclear Information System (INIS)

    Zafar, H.; Hayyat, A.; Akhtar, N.

    2013-01-01

    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. (author)

  15. An unusual case of osteonecrosis of the jaw associated with dengue fever and periodontitis.

    Science.gov (United States)

    Indurkar, M S; Sethi, R

    2016-03-01

    Osteonecrosis is a disorder rarely occurring 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 a history of dengue infection. We also diagnosed symptoms of chronic periodontitis, which may have potentiated the necrosis. This case report will describe a novel clinical presentation and management of osteonecrosis of the jaw (ONJ) of unknown origin and a possible pathogenesis explaining the association of ONJ with dengue fever and periodontitis. © 2015 Australian Dental Association.

  16. The extinction of dengue through natural vulnerability of its vectors.

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    Craig R Williams

    Full Text Available BACKGROUND: Dengue is the world's most important mosquito-borne viral illness. Successful future management of this disease requires an understanding of the population dynamics of the vector, especially in the context of changing climates. Our capacity to predict future dynamics is reflected in our ability to explain the significant historical changes in the distribution and abundance of the disease and its vector. METHODOLOGY/PRINCIPAL FINDINGS: Here we combine daily weather records with simulation modelling techniques to explain vector (Aedes aegypti (L. persistence within its current and historic ranges in Australia. We show that, in regions where dengue presently occurs in Australia (the Wet Tropics region of Far North Queensland, conditions are persistently suitable for year-round adult Ae. aegypti activity and oviposition. In the historic range, however, the vector is vulnerable to periodic extinction due to the combined influence of adult activity constraints and stochastic loss of suitable oviposition sites. CONCLUSIONS/SIGNIFICANCE: These results, together with changes in water-storage behaviour by humans, can explain the observed historical range contraction of the disease vector. For these reasons, future eradication of dengue in wet tropical regions will be extremely difficult through classical mosquito control methods alone. However, control of Ae. aegypti in sub-tropical and temperate regions will be greatly facilitated by government policy regulating domestic water-storage. Exploitation of the natural vulnerabilities of dengue vectors (e.g., habitat specificity, climatic limitations should be integrated with the emerging novel transgenic and symbiotic bacterial control techniques to develop future control and elimination strategies.

  17. 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.

  18. Dengue fever: new paradigms for a changing epidemiology

    Directory of Open Access Journals (Sweden)

    Schimmer Barbara

    2005-03-01

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

  19. 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.

  20. Frequency, pattern and management of acute abdomen in dengue fever in Karachi, Pakistan.

    Science.gov (United States)

    Shamim, Muhammad

    2010-07-01

    This study aimed to determine the frequency, pattern and management of acute abdomen in patients with dengue fever. This descriptive case series is a prospective analysis of acute abdomen in dengue fever that was performed at three secondary care hospitals in Karachi, Pakistan from June 1, 2005 to December 31, 2008. The inclusion criterion was all patients with confirmed diagnosis of dengue fever. Patients with incomplete laboratory, ultrasound or histopathology data were excluded. Among 357 patients with dengue fever, 43 (12.04%) had acute abdomen. There were 15 men and 28 women, with a median age of 29 years. These included 26 cases of acute cholecystitis, 7 cases of acute appendicitis, 7 cases of nonspecific peritonitis, and 3 cases of acute pancreatitis. Dengue hemorrhagic fever/shock syndrome was found in acute pancreatitis, and two of these patients died. Emergency surgery was required in eight patients (5 appendectomy and 3 open cholecystectomy). Substantial transfusion of blood and its components was required in eight patients who underwent emergency surgery. Early diagnosis and prompt conservative management of dengue acute abdomen is necessary to avoid mortality and emergency surgery-related morbidity. However, if needed, surgery can be performed with acceptable morbidity. Copyright © 2010 Asian Surgical Association. Published by Elsevier B.V. All rights reserved.

  1. 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.

  2. Assessing dengue outbreak areas using vector surveillance in north east district, Penang Island, Malaysia

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    Ahmad Mohiddin

    2015-11-01

    Full Text Available Objective: To understand the efficacy of ovitrap surveillance and its implementation on monitoring reflection upon case occurrence in relation to climate variables. Methods: We used routinely setup ovitrap surveillance to monitor the mosquito populations in previous outbreak areas. Ovitraps were installed weekly at three localities that experienced high number of dengue cases (Flat Hamna, Kampung Sungai Gelugor and Kampung Tanjung Tokong from January 2010 to February 2011. Ovitraps and paddles were brought back to the laboratory and all of the water contents were poured into an enamel pan. Aged tap water was added into the enamel pan and eggs were allowed to hatch. The hatching larvae were counted after 3 days. The hatched larvae were identified at the 3rd instar larval stage. The ovitrap indices and mean number of larvae were analyzed using student t-test and One-way ANOVA. Spearmen’s rank correlation coefficient was used to determine the relation between meteorology variables and dengue fever cases. Results: Aedes albopictus was found as dominant species followed by Aedes aegypti recorded in all three study areas. Aedes aegypti preferred to breed outdoor with larvae collection, which was higher than indoor (72.37%. There was a positive correlation between the ovitrap index with the rainfall and humidity except in Kampung Tanjung Tokong. Our result also showed negative correlation between temperature and ovitrap index in all localities. Conclusions: This study provides useful data to be adapted in dengue vector management. It is very important to understand the fluctuation of vector population according to the seasonal activity, which can help us to improve our control programs. However, other factors might also contribute to the increment of dengue outbreak such as the number of available breeding sites, behavior of the vector against environmental factors and the cleanliness of the environment.

  3. Zoonotic and vector borne agents causing disease in adult patients hospitalized due to fever of unknown origin in Thailand

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    Soawapak Hinjoy

    2017-10-01

    Full Text Available Objective: To determine the etiologic agents of fever of unknown origin among populations in agricultural communities and to assess the possible risk factors for zoonotic infections. Methods: Hospitalized patients with fever of unknown origin under physician care were asked to participate and provide blood samples for laboratory tests and screening for endemic diseases at the hospitals. Samples were stored at –80 °C until they were tested at Chulalongkorn University to identify additional pathogens. Results: We were able to identify the etiologic agents in 24.6% of the 463 enrolled patients. Zoonotic and vector borne agents were confirmed in 59 cases (12.7%. Dengue virus (7.3% was the most frequently detected disease followed by scrub typhus (3.2%. There were two cases of comorbidities of scrub typhus and dengue fever. The other six cases of zoonoses were leptospirosis, melioidosis, and Streptococcus suis infections. Patients with zoonotic/vector borne agents noticed rats in their houses and reported having contact with livestock feces more frequently than those patients without zoonotic/vector borne agents. Conclusions: Dengue virus and scrub typhus were mostly detected in the rainy season. During this specific season, clinicians should raise awareness of those diseases when any patients are admitted to the hospital with fever of an unidentified source.

  4. Management experience of surgical complications of dengue fever patients at hameed latif hospital, Lahore

    International Nuclear Information System (INIS)

    Ahmad, F.

    2012-01-01

    Objective: This study was designed to determine the frequency, pattern and management of surgical complications among patients with dengue fever. Design: Cross sectional study design was used. Settings: Hameed Latif Hospital, Lahore. Methods: From March - 2009 to December - 2011 total of 875 patients of dengue fever with positive anti-dengue immunoglobulin M (IgM) serology were included in this study. Complete blood count, liver function test, blood urea, serum creatinin, serum amylase were determined in all patients admitted with the diagnosis of dengue fever. All the patients were evaluated for the presence of surgical complications by physical examination and real time ultrasound abdomen. Patient had CT - abdomen and brain where it was required. Patients having surgical complications were managed in dengue ward and ICU with multidisciplinary approach. Data entry and analysis was done by using SPSS 16. Results: Among 875 patients with dengue fever, 491 (43.9%) patients were men and 384 (48.9%) were women with age range (18 - 70) years. Surgical complications were detected in 121 (13.8%) patients: acute cholecystitis in 46 (5.26%); acute pancreatitis in 19 (2.17%); injection abscess in 14 (1.6%); gastrointestinal bleed in 24 (2.74%); forearm compartment syndrome in 3 (0.34%); abdominal compartment syndrome in 2 (0.23%) and acute appendicitis, 4 (0.46%) patients. Cerebral bleed, retroperitoneal hematoma, abdominal wall hematoma and splenic rupture was seen among 3 (0.34%), 2 (0.23%), 3 (0.34%), and 1 (0.11%) patients, respectively. Out of 121 patients surgery was done in 20 (16.5%) patients while rest of 101 (83.5%) patients were managed conservatively. Two patients died. Conclusion: Surgical complications are common and should be suspected in every patient with dengue fever. Majority of surgical manifestations of dengue fever were managed conservatively however surgical intervention was done in certain cases with favorable outcome. (author)

  5. 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

  6. PCA-MLP SVM distinction of salivary Raman spectra of dengue fever infection.

    Science.gov (United States)

    Radzol, A R M; Lee, Khuan Y; Mansor, W; Wong, P S; Looi, I

    2017-07-01

    Dengue fever (DF) is a disease of major concern caused by flavivirus infection. Delayed diagnosis leads to severe stages, which could be deadly. Of recent, non-structural protein (NS1) has been acknowledged as a biomarker, alternative to immunoglobulins for early detection of dengue in blood. Further, non-invasive detection of NS1 in saliva makes the approach more appealing. However, since its concentration in saliva is less than blood, a sensitive and specific technique, Surface Enhanced Raman Spectroscopy (SERS), is employed. Our work here intends to define an optimal PCA-SVM (Principal Component Analysis-Support Vector Machine) with Multilayer Layer Perceptron (MLP) kernel model to distinct between positive and negative NS1 infected samples from salivary SERS spectra, which, to the best of our knowledge, has never been explored. Salivary samples of DF positive and negative subjects were collected, pre-processed and analyzed. PCA and SVM classifier were then used to differentiate the SERS analyzed spectra. Since performance of the model depends on the PCA criterion and MLP parameters, both are examined in tandem. Its performance is also compared to our previous works on simulated NS1 salivary samples. It is found that the best PCA-SVM (MLP) model can be defined by 95 PCs from CPV criterion with P1 and P2 values of 0.01 and -0.2 respectively. A classification performance of [76.88%, 85.92%, 67.83%] is achieved.

  7. Birth of a normal child after in vitro fertilization treatment followed by dengue fever.

    Science.gov (United States)

    Geber, Selmo; Coimbra, Bruna Barbosa; Geber, Guilherme Primo; Sampaio, Marcos

    2014-11-01

    Dengue is a serious public health issue due to its escalating aspect. It is also not yet established whether dengue has any impact on the outcome of assisted reproductive technique for infertility treatments. To our knowledge there are no published data in this subject. Therefore we describe a successful case of birth after in vitro fertilization (IVF) followed by dengue fever. A couple with primary unexplained infertility was submitted to IVF. The patient was submitted to ovulation induction with long protocol. A total of 12 oocytes were retrieved and two embryos were transferred. On the evening of the embryo transfer the patient started with headache and retro-orbital pain, followed by fever and nausea. Two days later she started with vomiting and diarrhea and epistaxis. The tourniquet test was positive. After patient's exams showed hemoconcentration and low platelet count (<50,000/mm(3)) the diagnosis of dengue hemorrhagic fever was confirmed and she was hospitalized and parenterally hydrated. As there was a good response to treatment, the patient was discharged the next day. A serum βhCG concentration 14 days after oocyte retrieval was positive. A healthy infant was born at the thirty-ninth gestational week by cesarean section. To our knowledge this is the first successful case reported on a patient who had dengue fever immediately after embryo transfer in an IVF treatment cycle. As dengue becomes a public health problem, it is important to bring attention to the subject.

  8. Computational Intelligence Method for Early Diagnosis Dengue Haemorrhagic Fever Using Fuzzy on Mobile Device

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    Salman Afan

    2014-03-01

    Full Text Available 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. Neurological complications of dengue fever: Experience from a tertiary center of north India

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    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.

  10. Dengue vector dynamics (Aedes aegypti influenced by climate and social factors in Ecuador: implications for targeted control.

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    Anna M Stewart Ibarra

    Full Text Available BACKGROUND: Dengue fever, a mosquito-borne viral disease, is now the fastest spreading tropical disease globally. Previous studies indicate that climate and human behavior interact to influence dengue virus and vector (Aedes aegypti population dynamics; however, the relative effects of these variables depends on local ecology and social context. We investigated the roles of climate and socio-ecological factors on Ae. aegypti population dynamics in Machala, a city in southern coastal Ecuador where dengue is hyper-endemic. METHODS/PRINCIPAL FINDINGS: We studied two proximate urban localities where we monitored weekly Ae. aegypti oviposition activity (Nov. 2010-June 2011, conducted seasonal pupal surveys, and surveyed household to identify dengue risk factors. The results of this study provide evidence that Ae. aegypti population dynamics are influenced by social risk factors that vary by season and lagged climate variables that vary by locality. Best-fit models to predict the presence of Ae. aegypti pupae included parameters for household water storage practices, access to piped water, the number of households per property, condition of the house and patio, and knowledge and perceptions of dengue. Rainfall and minimum temperature were significant predictors of oviposition activity, although the effect of rainfall varied by locality due to differences in types of water storage containers. CONCLUSIONS: These results indicate the potential to reduce the burden of dengue in this region by conducting focused vector control interventions that target high-risk households and containers in each season and by developing predictive models using climate and non-climate information. These findings provide the region's public health sector with key information for conducting time and location-specific vector control campaigns, and highlight the importance of local socio-ecological studies to understand dengue dynamics. See Text S1 for an executive summary in

  11. Spatiotemporal analysis of indigenous and imported dengue fever cases in Guangdong province, China

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    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.

  12. Dengue Epidemiology

    Science.gov (United States)

    ... and dengue shock syndrome (DSS). Transmission of the Dengue Virus Dengue is transmitted between people by the ... the vectors is too infrequent to sustain transmission. Dengue is an Emerging Disease The four dengue viruses ...

  13. Spatiotemporal responses of dengue fever transmission to the road network in an urban area.

    Science.gov (United States)

    Li, Qiaoxuan; Cao, Wei; Ren, Hongyan; Ji, Zhonglin; Jiang, Huixian

    2018-07-01

    Urbanization is one of the important factors leading to the spread of dengue fever. Recently, some studies found that the road network as an urbanization factor affects the distribution and spread of dengue epidemic, but the study of relationship between the distribution of dengue epidemic and road network is limited, especially in highly urbanized areas. This study explores the temporal and spatial spread characteristics of dengue fever in the distribution of road network by observing a dengue epidemic in the southern Chinese cities. Geographic information technology is used to extract the spatial location of cases and explore the temporal and spatial changes of dengue epidemic and its spatial relationship with road network. The results showed that there was a significant "severe" period in the temporal change of dengue epidemic situation, and the cases were mainly concentrated in the vicinity of narrow roads, the spread of the epidemic mainly along the high-density road network area. These results show that high-density road network is an important factor to the direction and scale of dengue epidemic. This information may be helpful to the development of related epidemic prevention and control strategies. Copyright © 2018. Published by Elsevier B.V.

  14. Rift Valley fever potential mosquito vectors and their infection status ...

    African Journals Online (AJOL)

    Background: Rift Valley fever (RVF) is a mosquito-borne viral zoonotic disease. Rift Valley fever virus (RVFV) has been isolated from more than 40 species of mosquitoes from eight genera. This study was conducted to determine the abundance of potential mosquito vectors and their RVFV infection status in Ngorongoro ...

  15. 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.

  16. Dengue fever in the San Juan Bay Estuary: Evaluating the Role of Wetland Ecosystem Services

    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 pr...

  17. Superior infectivity for mosquito vectors contributes to competitive displacement among strains of dengue virus

    Directory of Open Access Journals (Sweden)

    Schirtzinger Erin E

    2008-02-01

    Full Text Available Abstract Background Competitive displacement of a weakly virulent pathogen strain by a more virulent strain is one route to disease emergence. However the mechanisms by which pathogens compete for access to hosts are poorly understood. Among vector-borne pathogens, variation in the ability to infect vectors may effect displacement. The current study focused on competitive displacement in dengue virus serotype 3 (DENV3, a mosquito-borne pathogen of humans. In Sri Lanka in the 1980's, a native DENV3 strain associated with relatively mild dengue disease was displaced by an invasive DENV3 strain associated with the most severe disease manifestations, dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS, resulting in an outbreak of DHF/DSS. Here we tested the hypothesis that differences between the invasive and native strain in their infectivity for Aedes aegypti mosquitoes, the primary vector of DENV, contributed to the competitive success of the invasive strain Results To be transmitted by a mosquito, DENV must infect and replicate in the midgut, disseminate into the hemocoel, infect the salivary glands, and be released into the saliva. The ability of the native and invasive DENV3 strains to complete the first three steps of this process in Aedes aegypti mosquitoes was measured in vivo. The invasive strain infected a similar proportion of mosquitoes as the native strain but replicated to significantly higher titers in the midgut and disseminated with significantly greater efficiency than the native strain. In contrast, the native and invasive strain showed no significant difference in replication in cultured mosquito, monkey or human cells. Conclusion The invasive DENV3 strain infects and disseminates in Ae. aegypti more efficiently than the displaced native DENV3 strain, suggesting that the invasive strain is transmitted more efficiently. Replication in cultured cells did not adequately characterize the known phenotypic differences between

  18. Current status, challenges and perspectives in the development of vaccines against yellow fever, dengue, Zika and chikungunya viruses.

    Science.gov (United States)

    Silva, José V J; Lopes, Thaísa R R; Oliveira-Filho, Edmilson F de; Oliveira, Renato A S; Durães-Carvalho, Ricardo; Gil, Laura H V G

    2018-06-01

    Emerging and re-emerging viral infections transmitted by insect vectors (arthopode-borne viruses, arbovirus) are a serious threat to global public health. Among them, yellow fever (YFV), dengue (DENV), chikungunya (CHIKV) and Zika (ZIKV) viruses are particularly important in tropical and subtropical regions. Although vector control is one of the most used prophylactic measures against arboviruses, it often faces obstacles, such as vector diversity, uncontrolled urbanization and increasing resistance to insecticides. In this context, vaccines may be the best control strategy for arboviral diseases. Here, we provide a general overview about licensed vaccines and the most advanced vaccine candidates against YFV, DENV, CHIKV and ZIKV. In particular, we highlight vaccine difficulties, the current status of the most advanced strategies and discuss how the molecular characteristics of each virus can influence the choice of the different vaccine formulations. Copyright © 2018 Elsevier B.V. All rights reserved.

  19. Value of syndromic surveillance within the Armed Forces for early warning during a dengue fever outbreak in French Guiana in 2006

    Directory of Open Access Journals (Sweden)

    Jefferson Henry

    2008-07-01

    Full Text Available Abstract Background A dengue fever outbreak occured in French Guiana in 2006. The objectives were to study the value of a syndromic surveillance system set up within the armed forces, compared to the traditional clinical surveillance system during this outbreak, to highlight issues involved in comparing military and civilian surveillance systems and to discuss the interest of syndromic surveillance for public health response. Methods Military syndromic surveillance allows the surveillance of suspected dengue fever cases among the 3,000 armed forces personnel. Within the same population, clinical surveillance uses several definition criteria for dengue fever cases, depending on the epidemiological situation. Civilian laboratory surveillance allows the surveillance of biologically confirmed cases, within the 200,000 inhabitants. Results It was shown that syndromic surveillance detected the dengue fever outbreak several weeks before clinical surveillance, allowing quick and effective enhancement of vector control within the armed forces. Syndromic surveillance was also found to have detected the outbreak before civilian laboratory surveillance. Conclusion Military syndromic surveillance allowed an early warning for this outbreak to be issued, enabling a quicker public health response by the armed forces. Civilian surveillance system has since introduced syndromic surveillance as part of its surveillance strategy. This should enable quicker public health responses in the future.

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

    Science.gov (United States)

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

    2015-01-01

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

  1. 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.

  2. Risk Factors for the Presence of Chikungunya and Dengue Vectors (Aedes aegypti and Aedes albopictus), Their Altitudinal Distribution and Climatic Determinants of Their Abundance in Central Nepal

    Science.gov (United States)

    Dhimal, Meghnath; Gautam, Ishan; Joshi, Hari Datt; O’Hara, Robert B.; Ahrens, Bodo; Kuch, Ulrich

    2015-01-01

    Background The presence of the recently introduced primary dengue virus vector mosquito Aedes aegypti in Nepal, in association with the likely indigenous secondary vector Aedes albopictus, raises public health concerns. Chikungunya fever cases have also been reported in Nepal, and the virus causing this disease is also transmitted by these mosquito species. Here we report the results of a study on the risk factors for the presence of chikungunya and dengue virus vectors, their elevational ceiling of distribution, and climatic determinants of their abundance in central Nepal. Methodology/Principal Findings We collected immature stages of mosquitoes during six monthly cross-sectional surveys covering six administrative districts along an altitudinal transect in central Nepal that extended from Birgunj (80 m above sea level [asl]) to Dhunche (highest altitude sampled: 2,100 m asl). The dengue vectors Ae. aegypti and Ae. albopictus were commonly found up to 1,350 m asl in Kathmandu valley and were present but rarely found from 1,750 to 2,100 m asl in Dhunche. The lymphatic filariasis vector Culex quinquefasciatus was commonly found throughout the study transect. Physiographic region, month of collection, collection station and container type were significant predictors of the occurrence and co-occurrence of Ae. aegypti and Ae. albopictus. The climatic variables rainfall, temperature, and relative humidity were significant predictors of chikungunya and dengue virus vectors abundance. Conclusions/Significance We conclude that chikungunya and dengue virus vectors have already established their populations up to the High Mountain region of Nepal and that this may be attributed to the environmental and climate change that has been observed over the decades in Nepal. The rapid expansion of the distribution of these important disease vectors in the High Mountain region, previously considered to be non-endemic for dengue and chikungunya fever, calls for urgent actions to

  3. 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.

  4. A multi-country study of the economic burden of dengue fever: Vietnam, Thailand, and Colombia.

    Science.gov (United States)

    Lee, Jung-Seok; Mogasale, Vittal; Lim, Jacqueline K; Carabali, Mabel; Lee, Kang-Sung; Sirivichayakul, Chukiat; Dang, Duc Anh; Palencia-Florez, Diana Cristina; Nguyen, Thi Hien Anh; Riewpaiboon, Arthorn; Chanthavanich, Pornthep; Villar, Luis; Maskery, Brian A; Farlow, Andrew

    2017-10-01

    Dengue fever is a major public health concern in many parts of the tropics and subtropics. The first dengue vaccine has already been licensed in six countries. Given the growing interests in the effective use of the vaccine, it is critical to understand the economic burden of dengue fever to guide decision-makers in setting health policy priorities. A standardized cost-of-illness study was conducted in three dengue endemic countries: Vietnam, Thailand, and Colombia. In order to capture all costs during the entire period of illness, patients were tested with rapid diagnostic tests on the first day of their clinical visits, and multiple interviews were scheduled until the patients recovered from the current illness. Various cost items were collected such as direct medical and non-medical costs, indirect costs, and non-out-of-pocket costs. In addition, socio-economic factors affecting disease severity were also identified by adopting a logit model. We found that total cost per episode ranges from $141 to $385 for inpatient and from $40 to $158 outpatient, with Colombia having the highest and Thailand having the lowest. The percentage of the private economic burden of dengue fever was highest in the low-income group and lowest in the high-income group. The logit analyses showed that early treatment, higher education, and better knowledge of dengue disease would reduce the probability of developing more severe illness. The cost of dengue fever is substantial in the three dengue endemic countries. Our study findings can be used to consider accelerated introduction of vaccines into the public and private sector programs and prioritize alternative health interventions among competing health problems. In addition, a community would be better off by propagating the socio-economic factors identified in this study, which may prevent its members from developing severe illness in the long run.

  5. Dengue Fever Seroprevalence and Risk Factors, Texas-Mexico Border, 2004

    Centers for Disease Control (CDC) Podcasts

    Dengue fever is both endemic and underrecognized along a section of the southern Texas–Mexico border, and low income is a primary risk factor for infection. As part of a special section on Global Poverty and Human Development, Dr. Joan Marie Brunkard discusses a dengue seroprevalence survey in this region and what can be done to help prevent infection and to identify and treat those who are infected.

  6. Population of Aedes sp in Highland of Wonosobo District and Its Competence as A Dengue Vector

    Science.gov (United States)

    Martini, Martini; Widjanarko, Bagoes; Hestiningsih, Retno; Purwantisari, Susiana; Yuliawati, Sri

    2017-02-01

    The increased cases of dengue fever have occurred in the highland of Wonosobo District, and the epidemic taken place in 2009 had 59.3 cases per 100,000 populations. This study aimed to describe of vector competence of the mosquitoes as a dengue vector in the highland of Wonosobo District, Central Java Province. The serial laboratory work was done to measure of vector competence complementary with vector bionomic study. The samples were 20 villages, which were located at Wonosobo sub district. Every village was observed about 15-20 houses. The observed variables were vector competition, bionomic and transovarial infection level, and titer of virus on the mosquitoes after injection. Immunohistochemistry or IHC methods were used to identify transovarial infection status. The number of Ae. aegypti and Ae. albopictus were almost similar and both were found indoors or outdoors. Based on HI and OI index, the larvae density in the highland was enough high than standard of the program. Transovarial infection was found on Ae. aegypti and Ae. albopictus. Environment parameters such as temperature and relative humidity fulfilled the optimum requirement to support the vectors’ life cycle. Transovarial infection has been proven, thus, it indicates that the local transmission has been occurred in this area. Titer of virus was also increasing after day per day. This indicate that the mosquitoes has the ability being vector. As used to do in other area, it is important to conduct breeding places elimination (PSN) indoors as well as outdoors, through active participation of the community in highland area.

  7. 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

  8. 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

  9. 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

  10. Dengue fever as a cause of hemophagocytic lymphohistiocytosis

    OpenAIRE

    Hein, Noely; Bergara, Gabriel Heiser; Moura, Nathalie Bianchini Vieira; Cardoso, D?bora Morais; Hirose, Maki; Ferronato, Angela Esp?sito; Pastorino, Ant?nio Carlos; Lo, Denise Swei; Gilio, Alfredo Elias

    2015-01-01

    Dengue is endemic in more than 100 countries in Southeast Asia, the Americas, the western Pacific, Africa and the eastern Mediterranean regions. The virus is transmitted by Aedes mosquitoes. Dengue disease is the most prevalent arthropod-borne viral disease in humans and is a global and national public health concern in several countries. A seasonal pattern of dengue disease is consistently observed. The highest incidences usually correspond to the period of highest rainfall and humidity, pro...

  11. IL-10 and socs3 Are Predictive Biomarkers of Dengue Hemorrhagic Fever

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    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.

  12. In silico prediction of monovalent and chimeric tetravalent vaccines for prevention and treatment of dengue fever.

    Science.gov (United States)

    Vijayakumar, Subramaniyan; Ramesh, Venkatachalam; Prabhu, Srinivasan; Manogar, Palani

    2017-11-01

    Reverse vaccinology method was used to predict the monovalent peptide vaccine candidate to produce antibodies for therapeutic purpose and to predict tetravalent vaccine candidate to act as a common vaccine to cover all the fever dengue virus serotypes. Envelope (E)-proteins of DENV-1-4 serotypes were used for vaccine prediction using NCBI, Uniprot/Swissprot, Swiss-prot viewer, VaxiJen V2.0, TMHMM, BCPREDS, Propred-1, Propred and MHC Pred,. E-proteins of DENV-1-4 serotypes were identified as antigen from which T cell epitopes, through B cell epitopes, were predicted to act as peptide vaccine candidates. Each selected T cell epitope of E-protein was confirmed to act as vaccine and to induce complementary antibody against particular serotype of dengue virus. Chimeric tetravalent vaccine was formed by the conjugation of four vaccines, each from four dengue serotypes to act as a common vaccine candidate for all the four dengue serotypes. It can be justifiably concluded that the monovalent 9-mer T cell epitope for each DENV serotypes can be used to produce specific antibody agaomst dengue virus and a chimeric common tetravalent vaccine candidate to yield a comparative vaccine to cover any of the four dengue virus serotype. This vaccine is expected to act as highly immunogenic against preventing dengue fever.

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

    Science.gov (United States)

    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. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. The dengue vaccine pipeline: Implications for the future of dengue control

    OpenAIRE

    Schwartz, Lauren M.; Halloran, M. Elizabeth; Durbin, Anna P.; Longini Jr., Ira M.

    2015-01-01

    Dengue has become the most rapidly expanding mosquito-borne infectious disease on the planet, surpassing malaria and infecting at least 390 million people per year. There is no effective treatment for dengue illness other than supportive care, especially for severe cases. Symptoms can be mild or life-threatening as in dengue hemorrhagic fever and dengue shock syndrome. Vector control has been only partially successful in decreasing dengue transmission. The potential use of safe and effective ...

  15. Achados ultra-sonográficos abdominais em pacientes com dengue Abdominal ultrasound findings in patients with dengue fever

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    Karen Amaral do Vabo

    2004-06-01

    Full Text Available OBJETIVO: Apresentar os achados ultra-sonográficos abdominais em pacientes com dengue e compará-los aos descritos na literatura. MATERIAIS E MÉTODOS: Foram realizados exames ultra-sonográficos abdominais de 38 pacientes, 25 do sexo feminino e 13 do sexo masculino, com idade média de 35 anos, com diagnóstico de dengue sorologicamente confirmado. Os achados foram comparados com os descritos na literatura. RESULTADOS: Os achados ultra-sonográficos mais relevantes foram espessamento difuso da parede da vesícula biliar em 18 casos (47,4%, líquido livre na cavidade abdominal e/ou pélvica em 12 (31,6%, esplenomegalia em 11 (28,9%, hepatomegalia em 10 (26,3% e líquido pericolecístico em 10 (26,3%. Vinte e seis por cento dos pacientes apresentaram exames ultra-sonográficos normais. CONCLUSÃO: Os achados ultra-sonográficos abdominais são uma ferramenta adicional útil na confirmação de casos suspeitos de dengue hemorrágica e na detecção precoce da gravidade e da progressão da doença, sendo de extrema importância para o radiologista o conhecimento destes possíveis achados.OBJECTIVE: To review the abdominal ultrasound findings in patients with serologically proven dengue fever and to compare the results with data from the literature. MATERIALS AND METHODS: Thirty-eight patients with serologically proven dengue fever, 25 female and 13 male, mean age of 35 years, were submitted to abdominal ultrasound. The ultrasound findings were compared with data from the literature. RESULTS: The most relevant ultrasound findings were diffuse gallbladder wall thickening in 18 cases (47.4%, abdominal and/or pelvic free fluid in 12 (31.6%, splenomegaly in 11 (28.9%, hepatomegaly in 10 (26.3% and perivesicular fluid in 10 (26.3%. Twenty-six percent of the patients had normal abdominal ultrasound. CONCLUSION: Abdominal sonography is a useful additional diagnostic tool for the confirmation of suspected cases of dengue hemorrhagic fever and for the

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

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    Brinda J

    2017-01-01

    Full Text Available BACKGROUND Dengue infection is viral infection with different clinical presentation. This study was conducted in Kanyakumari Government Medical College Hospital, Asaripallam, Tamil Nadu, to study the various clinical profile and polyserositis involvement in dengue. MATERIALS AND METHODS The clinical profile and polyserositis involvement in dengue infection were determined by the retrospective study of all dengue infection in Kanyakumari Government Medical College Hospital, Asaripallam, Nagercoil, Tamilnadu. It was a retrospective study. All probable cases that had high-grade fever, lymphadenopathy, hepatomegaly, features of hock or haemorrhage and so forth and were admitted with provisional diagnosis of dengue fever were taken into account. All patients with positive dengue tests, either NS1 antigen, IgM, IgG antibody rapid serological test kit or ELISA were taken into the study group. As the duration of history of fever might be fallacious, the patients were subjected to all three serological tests. Patients who were positive for malaria, meningitis and enteric fever were excluded from the study. The whole number of patients included in our study was 40 (=40. RESULTS In this study, it was found that the bleeding manifestation had no correlation with thrombocytopenia, hepatomegaly and raised SGOT. All 40 patients had fever and they were treated with antipyretics (paracetamol in appropriate doses. Patients who presented with warning signs and stable vital signs were initially encouraged to take oral fluids; if they were not tolerated, intravenous fluids were started according to the WHO guidelines. CONCLUSION Dengue is an important arboviral infection in tropical countries. 1 Global incidence of dengue fever has increased dramatically in the recent decades. There are very few studies based on the revised new dengue classification. In our study, the total number of cases analysed was 40, out of which 28 (70% were categorised as cases of non

  17. Serum Metabolomics Reveals Serotonin as a Predictor of Severe Dengue in the Early Phase of Dengue Fever

    Science.gov (United States)

    Thein, Tun Linn; Fang, Jinling; Pang, Junxiong; Ooi, Eng Eong; Leo, Yee Sin; Ong, Choon Nam; Tannenbaum, Steven R.

    2016-01-01

    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. PMID:27055163

  18. Integrated Strategies for the Control and Prevention of Dengue Vectors with Particular Reference to Aedes aegypti

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    Asghar Abbas

    2014-01-01

    Full Text Available Dengue fever (DF is one of the most threatening vector borne diseases, affecting both humans and animals, causing severe epidemics and has brought the world to take serious steps for its control and prevention. DF is a viral disease transmitted by Aedes mosquitoes. Unfortunately, due to unavailability of vaccine and lack of effective treatment, emphasis is given on its vector control. The only option left for its eradication is to restrict mosquito breeding. This can be achieved by chemical, biological and environment management methods. Use of botanicals is also an alternate and probably most effective approach for controlling DF vector. Community based eradication campaigns including educating people about its prevention and control meseaures and personal prophylaxis also play a vital role to prevent its occurrence. Likewise, use of nanotechnology and micro-emulsion, use of pheromones, insect sterilization techniques has also shown promising results in vector control. Utilization of only one method cannot control this dangerous disease but combination of all above interventions, discussed in the present paper, may prevent the DF vector and ultimately might help in the eradication programs of this disease.

  19. Effectiveness of a fluid chart in outpatient management of suspected dengue fever: A pilot study.

    Science.gov (United States)

    Nasir, Nazrila Hairin; Mohamad, Mohazmi; Lum, Lucy Chai See; Ng, Chirk Jenn

    2017-01-01

    Dengue infection is the fastest spreading mosquito-borne viral disease in the world. One of the complications of dengue is dehydration which, if not carefully monitored and treated, may lead to shock, particularly in those with dengue haemorrhagic fever. WHO has recommended oral fluid intake of five glasses or more for adults who are suspected to have dengue fever. However, there have been no published studies looking at self-care intervention measures to improve oral fluid intake among patients suspected of dengue fever. To assess the feasibility and effectiveness of using a fluid chart to improve oral fluid intake in patients with suspected dengue fever in a primary care setting. This feasibility study used a randomized controlled study design. The data was collected over two months at a primary care clinic in a teaching hospital. The inclusion criteria were: age > 12 years, patients who were suspected to have dengue fever based on the assessment by the primary healthcare clinician, fever for > three days, and thrombocytopenia (platelets dengue home care card. The intervention group received the fluid chart and a cup (200ml). Baseline clinical and laboratory data, 24-hour fluid recall (control group), and fluid chart were collected. The main outcomes were: hospitalization rates, intravenous fluid requirement and total oral fluid intake. Among the 138 participants who were included in the final analysis, there were fewer hospital admissions in the intervention group (n = 7, 10.0%) than the control group (n = 12, 17.6%) (p = 0.192). Similarly, fewer patients (n = 9, 12.9%) in the intervention group required intravenous fluid compared to the control group (n = 15, 22.1%), (p = 0.154). There was an increase in the amount of daily oral fluid intake in the intervention group (about 3,000 ml) compared to the control group (about 2,500 ml, p = 0.521). However, these differences did not reach statistical significance. This is a feasible and acceptable study to perform in

  20. 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.

  1. Aedes (Stegomyia) albopictus (Skuse), a potential new Dengue vector in southern Cameroon.

    OpenAIRE

    Fontenille, D.; Toto, J. C.

    2001-01-01

    Aedes albopictus, a mosquito vector of Dengue virus, has been recorded for the first time in Cameroon. Entomologic surveys in 2000 demonstrated that it is widespread in southern Cameroon, colonizing a wide variety of breeding sites and biting humans in every district surveyed. The presence of this vector increases the risk for emergence of dengue in Cameroon.

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

    Science.gov (United States)

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

    2015-02-01

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

  3. 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.

  4. Epidemiology of dengue fever in Hanoi from 2002 to 2010 and its meteorological determinants

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    Dao Thi Minh An

    2014-12-01

    Full Text Available Background: Dengue fever (DF is a growing public health problem in Vietnam. The disease burden in Vietnam has been increasing for decades. In Hanoi, in contrast to many other regions, extrinsic drivers such as weather have not been proved to be predictive of disease frequency, which limits the usefulness of such factors in an early warning system. Aims: The purpose of this research was to review the epidemiology of DF transmission and investigate the role of weather factors contributing to occurrence of DF cases. Methods: Monthly data from Hanoi (2002–2010 were used to test the proposed model. Descriptive time-series analysis was conducted. Stepwise multivariate linear regression analysis assuming a negative binomial distribution was established through several models. The predictors used were lags of 1–3 months previous observations of mean rainfall, mean temperature, DF cases, and their interactions. Results: Descriptive analysis showed that DF occurred annually and seasonally with an increasing time trend in Hanoi. The annual low occurred from December to March followed by a gradual increase from April to July with a peak in September, October. The amplitude of the annual peak varied between years. Statistically significant relationships were estimated at lag 1–3 with rainfall, autocorrelation, and their interaction while temperature was estimated as influential at lag 3 only. For these relationships, the final model determined a correlation of 92% between predicted number of dengue cases and the observed dengue disease frequencies. Conclusions: Although the model performance was good, the findings suggest that other forces related to urbanization, density of population, globalization with increasing transport of people and goods, herd immunity, government vector control capacity, and changes in serotypes are also likely influencing the transmission of DF. Additional research taking into account all of these factors besides climatic

  5. International team with Virginia Tech participation maps genome of dengue and yellow fever mosquito

    OpenAIRE

    Trulove, Susan

    2007-01-01

    Developing new strategies to prevent and control yellow fever and dengue fever has become more possible with the completion of the first draft of the genome sequence of Aedes aegypti mosquito by scientists led by Vishvanath Nene at The Institute for Genomic Research (TIGR) and David Severson at the University of Notre Dame. The genome is the complete set of genetic material including genes and other segments of DNA in an organism.

  6. A successful management of dengue fever in pregnancy: Report of two cases

    Directory of Open Access Journals (Sweden)

    Singh N

    2008-01-01

    Full Text Available In the most recent outbreak of degue fever in India, we encountered at least seven cases of fever with thrombocytopenia in pregnancy but only two were seropositive for dengue. In one of the cases there was postpartum hemorrhage while in the other case there was perinatal transmission to the neonate requiring platelet transfusions. The diagnostic difficulties in pregnancy and the management are discussed.

  7. Assessing socioeconomic vulnerability to dengue fever in Cali, Colombia: statistical vs expert-based modeling.

    Science.gov (United States)

    Hagenlocher, Michael; Delmelle, Eric; Casas, Irene; Kienberger, Stefan

    2013-08-14

    As a result of changes in climatic conditions and greater resistance to insecticides, many regions across the globe, including Colombia, have been facing a resurgence of vector-borne diseases, and dengue fever in particular. Timely information on both (1) the spatial distribution of the disease, and (2) prevailing vulnerabilities of the population are needed to adequately plan targeted preventive intervention. We propose a methodology for the spatial assessment of current socioeconomic vulnerabilities to dengue fever in Cali, a tropical urban environment of Colombia. Based on a set of socioeconomic and demographic indicators derived from census data and ancillary geospatial datasets, we develop a spatial approach for both expert-based and purely statistical-based modeling of current vulnerability levels across 340 neighborhoods of the city using a Geographic Information System (GIS). The results of both approaches are comparatively evaluated by means of spatial statistics. A web-based approach is proposed to facilitate the visualization and the dissemination of the output vulnerability index to the community. The statistical and the expert-based modeling approach exhibit a high concordance, globally, and spatially. The expert-based approach indicates a slightly higher vulnerability mean (0.53) and vulnerability median (0.56) across all neighborhoods, compared to the purely statistical approach (mean = 0.48; median = 0.49). Both approaches reveal that high values of vulnerability tend to cluster in the eastern, north-eastern, and western part of the city. These are poor neighborhoods with high percentages of young (i.e., local expertise, statistical approaches could be used, with caution. By decomposing identified vulnerability "hotspots" into their underlying factors, our approach provides valuable information on both (1) the location of neighborhoods, and (2) vulnerability factors that should be given priority in the context of targeted intervention

  8. Nine year trends of dengue virus infection in Mumbai, Western India

    OpenAIRE

    Shastri, Jayanthi; Williamson, Manita; Vaidya, Nilima; Agrawal, Sachee; Shrivastav, Om

    2017-01-01

    Introduction: Dengue virus (DENV) causes a wide range of diseases in humans, from acute febrile illness Dengue fever (DF) to life-threatening Dengue hemorrhagic fever (DHF) or Dengue shock syndrome (DSS). Factors believed to be responsible for spread of Dengue virus infection include explosive population growth, unplanned urban overpopulation with inadequate public health systems, poor standing water and vector control, climate changes and increased international recreational, business, milit...

  9. Improving Dengue Virus Capture Rates in Humans and Vectors in Kamphaeng Phet Province, Thailand, Using an Enhanced Spatiotemporal Surveillance Strategy

    Science.gov (United States)

    Thomas, Stephen J.; Aldstadt, Jared; Jarman, Richard G.; Buddhari, Darunee; Yoon, In-Kyu; Richardson, Jason H.; Ponlawat, Alongkot; Iamsirithaworn, Sopon; Scott, Thomas W.; Rothman, Alan L.; Gibbons, Robert V.; Lambrechts, Louis; Endy, Timothy P.

    2015-01-01

    Dengue is of public health importance in tropical and sub-tropical regions. Dengue virus (DENV) transmission dynamics was studied in Kamphaeng Phet Province, Thailand, using an enhanced spatiotemporal surveillance of 93 hospitalized subjects with confirmed dengue (initiates) and associated cluster individuals (associates) with entomologic sampling. A total of 438 associates were enrolled from 208 houses with household members with a history of fever, located within a 200-m radius of an initiate case. Of 409 associates, 86 (21%) had laboratory-confirmed DENV infection. A total of 63 (1.8%) of the 3,565 mosquitoes collected were dengue polymerase chain reaction positive (PCR+). There was a significant relationship between spatial proximity to the initiate case and likelihood of detecting DENV from associate cases and Aedes mosquitoes. The viral detection rate from human hosts and mosquito vectors in this study was higher than previously observed by the study team in the same geographic area using different methodologies. We propose that the sampling strategy used in this study could support surveillance of DENV transmission and vector interactions. PMID:25986580

  10. Dengue hemorrhagic fever complicated with acute liver failure: a case report.

    Science.gov (United States)

    Dalugama, Chamara; Gawarammana, Indika Bandara

    2017-12-08

    Dengue is a common arboviral infection with a clinically diverse spectrum of presentations. Although hepatic dysfunction is commonly identified in patients will dengue illness, acute liver failure is rare. The etiopathogenesis of hepatic dysfunction is multifactorial and related to direct viral invasion of hepatocytes, immunological factors and hypoxia particularly in cases of shock in dengue hemorrhagic fever. Ideal management of dengue-related hepatic dysfunction and acute liver failure is still debated. We report a 53-year-old Sri Lankan Sinhalese male with serologically confirmed dengue fever presenting with evidence of plasma leakage developing acute liver failure evidenced by deranged liver functions, coagulopathy and altered sensorium. In addition to the 'standard care', the patient was managed with intravenous N-acetyl cysteine and blood transfusions even in the absence of bleeding or dropping packed cell volume (PCV), targeting a higher PCV in anticipation of better oxygenation at tissue level. He made a full recovery with no sequential infections. N-acetyl cysteine and packed cell transfusion aiming at a higher PCV to maintain adequate tissue perfusion during shock may be beneficial in acute liver failure due to dengue virus. Large randomized trials should be carried out to establish the efficacy of these treatment strategies to support these observations and change the current practice.

  11. Malaria and Other Vector-Borne Infection Surveillance in the U.S. Department of Defense Armed Forces Health Surveillance Center-Global Program: Review of 2009 Accomplishments

    Science.gov (United States)

    2011-03-04

    Vector borne infections (VBIs) such as malaria, dengue fever, yellow fever, scrub typhus , and plague comprise a significant proportion of the global...a VBI: scrub typhus (19), murine typhus (three), Japanese encephalitis (JE) (two), primary dengue infection (12), secondary dengue infection (nine...prioritized by GSRI, half are VBIs (malaria, dengue fever, Rift Valley fever, Chikungunya, CCHF, sandfly fever, O’nyong-nyong, Sindbis virus, scrub typhus

  12. Epidemic dengue and dengue hemorrhagic fever at the Texas-Mexico border: results of a household-based seroepidemiologic survey, December 2005.

    Science.gov (United States)

    Ramos, Mary M; Mohammed, Hamish; Zielinski-Gutierrez, Emily; Hayden, Mary H; Lopez, Jose Luis Robles; Fournier, Marta; Trujillo, Alfredo Rodríguez; Burton, Roy; Brunkard, Joan M; Anaya-Lopez, Luis; Banicki, Allison Abell; Morales, Pablo Kuri; Smith, Brian; Muñoz, Jorge L; Waterman, Stephen H

    2008-03-01

    A dengue-2 epidemic causing dengue hemorrhagic fever (DHF) occurred in the contiguous border cities of Matamoros, Tamaulipas (Mexico), and Brownsville, TX, in 2005. In December, we conducted a household-based epidemiologic survey to determine the incidence and seroprevalence of dengue infection among Matamoros and Brownsville residents and to identify risk factors associated with infection. Antibodies to dengue were measured in 273 individuals. The estimated incidence of recent dengue infection was 32% and 4% among Matamoros and Brownsville participants, respectively. The estimated prevalence of past dengue infection was 77% and 39% among Matamoros and Brownsville participants, respectively. The Breteau index was 28 in Matamoros and 16 in Brownsville, reflecting an abundant winter population of Aedes mosquitoes. Discarded waste tires and buckets were the two largest categories of infested containers found in both cities. Our results underscore the risk for epidemic dengue and DHF in the Texas-Mexico border region.

  13. Predicting the mortality in geriatric patients with dengue fever

    Science.gov (United States)

    Huang, Hung-Sheng; Hsu, Chien-Chin; Ye, Je-Chiuan; Su, Shih-Bin; Huang, Chien-Cheng; Lin, Hung-Jung

    2017-01-01

    Abstract Geriatric patients have high mortality for dengue fever (DF); however, there is no adequate method to predict mortality in geriatric patients. Therefore, we conducted this study to develop a tool in an attempt to address this issue. We conducted a retrospective case–control study in a tertiary medical center during the DF outbreak in Taiwan in 2015. All the geriatric patients (aged ≥65 years) who visited the study hospital between September 1, 2015, and December 31, 2015, were recruited into this study. Variables included demographic data, vital signs, symptoms and signs, comorbidities, living status, laboratory data, and 30-day mortality. We investigated independent mortality predictors by univariate analysis and multivariate logistic regression analysis and then combined these predictors to predict the mortality. A total of 627 geriatric DF patients were recruited, with a mortality rate of 4.3% (27 deaths and 600 survivals). The following 4 independent mortality predictors were identified: severe coma [Glasgow Coma Scale: ≤8; adjusted odds ratio (AOR): 11.36; 95% confidence interval (CI): 1.89–68.19], bedridden (AOR: 10.46; 95% CI: 1.58–69.16), severe hepatitis (aspartate aminotransferase >1000 U/L; AOR: 96.08; 95% CI: 14.11–654.40), and renal failure (serum creatinine >2 mg/dL; AOR: 6.03; 95% CI: 1.50–24.24). When we combined the predictors, we found that the sensitivity, specificity, positive predictive value, and negative predictive value for patients with 1 or more predictors were 70.37%, 88.17%, 21.11%, and 98.51%, respectively. For patients with 2 or more predictors, the respective values were 33.33%, 99.44%, 57.14%, and 98.51%. We developed a new method to help decision making. Among geriatric patients with none of the predictors, the survival rate was 98.51%, and among those with 2 or more predictors, the mortality rate was 57.14%. This method is simple and useful, especially in an outbreak. PMID:28906367

  14. Retroperitoneal Haematoma in a Patient with Dengue Haemorrhagic Fever: A Rare Case Report.

    Science.gov (United States)

    Singh, Jasminder; Singh, Harpreet; Sukhija, Gagandeep; Jagota, Ruchi; Bala, Saroj

    2016-11-01

    Dengue Haemorrhagic Fever (DHF) has diverse manifestations ranging from asymptomatic petechial skin haemorrhages to life threatening cerebral, pulmonary, gastrointestinal and genitourinary haemorrhages. However, the association of spontaneous retroperitoneal haematomas with DHF is not well documented in literature. We report a rare case of spontaneous retroperitoneal haematoma complicating DHF.

  15. WEB Services Implementation on The Report of Dengue Hemorrhagic Fever (DHF At Health Office Karanganyar

    Directory of Open Access Journals (Sweden)

    Ragil Saputra

    2013-06-01

    Full Text Available Abstract— Dengue Hemorrhagic Fever (DHF is one of the infectious diseases that frequently leads to Extraordinary Situation. The management of report is conducted by Health Community Center which subsequently gives report to Health Office. A problem arising from the report management is the fact that the report is conducted manually, therefore, the data is less valid and is not processed as quickly as possible. The quick and accurate data report system enables to lessen the risk of Dengue Hemorrhagic Fever. Due to this fact, it is undeniable necessary to provide an integrated inter-system of Dengue Fever report. This system includes an inter-system between one Health Community Center to another and to the system in Health Office. The integration of inter-system report is able to be conducted by the use of web service technology. Therefore, this research focuses on the development of Web Service based integrated system on the report of Dengue Fever. Data exchange is conducted in XML form by the application of SOAP and WSDL technologies. Library NuSOAP is necessary to provide class soapClient and soapServer. In other words, it functions as the listener whose functions are to receive and to respond at the access demand toward web service. The result is web service based report system which has dual functions since the system has functions to be either server or client. Keywords— web service, integration, SOAP, DHF.

  16. Notes from the Field: Outbreak of Locally Acquired Cases of Dengue Fever--Hawaii, 2015.

    Science.gov (United States)

    Johnston, David; Viray, Melissa; Ushiroda, Jenny; Whelen, A Christian; Sciulli, Rebecca; Gose, Remedios; Lee, Roland; Honda, Eric; Park, Sarah Y

    2016-01-22

    On October 21, 2015, the Hawaii Department of Health (HDOH) was notified of a positive dengue immunoglobulin M (IgM) antibody result in a woman residing on Hawaii Island (also known as the Big Island). The patient had no history of travel off the island, and other family members reported having similar signs and symptoms, which consisted of fever, headache, myalgias and arthralgias, and a generalized erythematous rash. HDOH initiated an investigation to identify any additional cases and potential exposure sources. On October 24, HDOH received report of a group of mainland U.S. visitors who had traveled together on Hawaii Island, including several who had developed a febrile illness. Additionally, on October 27, HDOH was notified of an unrelated person, also on Hawaii Island, with a positive dengue IgM result. As of November 26, 2015, HDOH had identified 107 laboratory-confirmed cases of dengue fever, with dates of onset ranging from September 11 to November 18, 2015.

  17. Severe coinfection of melioidosis and dengue fever in northeastern Brazil: first case report

    Directory of Open Access Journals (Sweden)

    Rafael Nogueira Macedo

    2012-02-01

    Full Text Available This report focuses on a fatality involving severe dengue fever and melioidosis in a 28-year-old truck driver residing in Pacoti in northeastern Brazil. He exhibited long-term respiratory symptoms (48 days and went through a wide-ranging clinical investigation at three hospitals, after initial clinical diagnoses of pneumonia, visceral leishmaniasis, tuberculosis, and fungal sepsis. After death, Burkholderia pseudomallei was isolated in a culture of ascitic fluid. Dengue virus type 1 was detected by polymerase chain reaction in cerebrospinal fluid (CSF; this infection was the cause of death. This description reinforces the need to consider melioidosis among the reported differential diagnoses of community-acquired infections where both melioidosis and dengue fever are endemic.

  18. Forecasting dengue hemorrhagic fever cases using ARIMA model: a case study in Asahan district

    Science.gov (United States)

    Siregar, Fazidah A.; Makmur, Tri; Saprin, S.

    2018-01-01

    Time series analysis had been increasingly used to forecast the number of dengue hemorrhagic fever in many studies. Since no vaccine exist and poor public health infrastructure, predicting the occurrence of dengue hemorrhagic fever (DHF) is crucial. This study was conducted to determine trend and forecasting the occurrence of DHF in Asahan district, North Sumatera Province. Monthly reported dengue cases for the years 2012-2016 were obtained from the district health offices. A time series analysis was conducted by Autoregressive integrated moving average (ARIMA) modeling to forecast the occurrence of DHF. The results demonstrated that the reported DHF cases showed a seasonal variation. The SARIMA (1,0,0)(0,1,1)12 model was the best model and adequate for the data. The SARIMA model for DHF is necessary and could applied to predict the incidence of DHF in Asahan district and assist with design public health maesures to prevent and control the diseases.

  19. People's knowledge and practice about dengue, its vectors, and control means in Brasilia (DF), Brazil: its relevance with entomological factors.

    Science.gov (United States)

    Dégallier, N; Vilarinhos, P T; de Carvalho, M S; Knox, M B; Caetano, J

    2000-06-01

    In South America, the epidemiology and ecology of dengue fever are strongly associated with human habits because the vector Aedes aegypti is strictly urban. Thus, the evaluation of people's knowledge and practice (PKP) is of great importance to improve integrated control measures. A PKP evaluation has been done in a suburb of Brasilia. Thirty questions were submitted to 130 habitants about income level, education, sources of information, specific knowledge about dengue, vector biology, and control measures applied. Other questions were about the responsibility of dengue control and the opportunity of applying a fine to people who would not cooperate with the control measures. Level of PKP was fairly high, either for housekeepers, workers, or students. The mosquito bite was cited as source of infection by 60.8% of interviewed people but 22.3% had no knowledge about this topic. The most cited symptoms in association with dengue were fever (73.1%), headache (66.2%), and rash (35.4%). Knowledge about mosquito biology and control was also fairly accurate, as demonstrated by 96.9% of answers. Elimination of water containers was the most efficient means according to 73% of people. Such action should be done mainly by the citizen (75.3% of answers). Despite the good PKP, correlations existed only between the PKP about vector biology and presence of potential breeding containers in March, and between the PKP about the disease and potential breeding containers in April. In conclusion, global educational campaigns may have a real impact on the PKP but this did not result in effective control of the mosquito breeding containers by the people.

  20. 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

  1. Spatio-temporal distribution of Aedes aegypti (Diptera: Culicidae mitochondrial lineages in cities with distinct dengue incidence rates suggests complex population dynamics of the dengue vector in Colombia.

    Directory of Open Access Journals (Sweden)

    Jeiczon Jaimes-Dueñez

    2015-04-01

    Full Text Available Aedes aegypti is the primary vector of the four serotypes of dengue virus (DENV1-4, Chikungunya and yellow fever virus to humans. Previous population genetic studies have revealed a particular genetic structure among the vector populations in the Americas that suggests differences in the ability to transmit DENV. In Colombia, despite its high epidemiologic importance, the genetic population structure and the phylogeographic depiction of Ae. aegypti, as well as its relationship with the epidemiologic landscapes in cities with heterogeneous incidence levels, remains unknown. We conducted a spatiotemporal analysis with the aim of determining the genetic structure and phylogeography of Colombian populations of Ae. aegypti among cities with different eco-epidemiologic characteristics with regard to DENV.Mitochondrial cytochrome oxidase C subunit 1 (COI--NADH dehydrogenase subunit 4 (ND4 genes were sequenced and analyzed from 341 adult mosquitoes collected during 2012 and 2013 in the Colombian cities of Bello, Riohacha and Villavicencio, which exhibit low, medium and high levels of incidence of DENV, respectively. The results demonstrated a low genetic differentiation over time and a high genetic structure between the cities due to changes in the frequency of two highly supported genetic groups. The phylogeographic analyses indicated that one group (associated with West African populations was found in all the cities throughout the sampling while the second group (associated with East African populations was found in all the samples from Bello and in only one sampling from Riohacha. Environmental factors such as the use of chemical insecticides showed a significant correlation with decreasing genetic diversity, indicating that environmental factors affect the population structure of Ae. aegypti across time and space in these cities.Our results suggest that two Ae. aegypti lineages are present in Colombia; one that is widespread and related to a West

  2. Involving urban communities in controlling dengue fever in Latin ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2016-05-04

    May 4, 2016 ... In addition to the public health threat it poses, dengue costs these economies billions of ... Production was greatest when water containers were outdoor, ... these successful interventions, some 250,000 households will benefit.

  3. Genetic differentiation in populations of Aedes aegypti (Diptera, Culicidae dengue vector from the Brazilian state of Maranhão

    Directory of Open Access Journals (Sweden)

    Andrelina Alves de Sousa

    2017-01-01

    Full Text Available Aedes (Stegomyia aegypti is the vector responsible for the transmission of the viruses that cause zika, yellow and chikungunya fevers, the four dengue fever serotypes (DENV – 1, 2, 3, 4, and hemorrhagic dengue fever in tropical and subtropical regions around the world. The present study investigated the genetic differentiation of the 15 populations of this vector in the Brazilian state of Maranhão, based on the mitochondrial ND4 marker. A total of 177 sequences were obtained for Aedes aegypti, with a fragment of 337 bps, 15 haplotypes, 15 polymorphics sites, haplotype diversity of h = 0.6938, and nucleotide diversity of π = 0.01486. The neutrality tests (D and Fs were not significant. The AMOVA revealed that most of the variation (58.47% was found within populations, with FST = 0.41533 (p < 0.05. Possible isolation by distance was tested and a significant correlation coefficient (r = 0.3486; p = 0.0040 was found using the Mantel test. The phylogenetic relationships among the 15 haplotypes indicated the existence of two distinct clades. This finding, together with the population parameters, was consistent with a pattern of genetic structuring that underpinned the genetic differentiation of the study populations in Maranhão, and was characterized by the presence of distinct lineages of Aedes aegypti. Keywords: Gene flow, Mitochondrial DNA, ND4

  4. Genetic differentiation in populations of Aedes aegypti (Diptera, Culicidae dengue vector from the Brazilian state of Maranhão

    Directory of Open Access Journals (Sweden)

    Andrelina Alves de Sousa

    Full Text Available ABSTRACT Aedes (Stegomyia aegypti is the vector responsible for the transmission of the viruses that cause zika, yellow and chikungunya fevers, the four dengue fever serotypes (DENV - 1, 2, 3, 4, and hemorrhagic dengue fever in tropical and subtropical regions around the world. The present study investigated the genetic differentiation of the 15 populations of this vector in the Brazilian state of Maranhão, based on the mitochondrial ND4 marker. A total of 177 sequences were obtained for Aedes aegypti, with a fragment of 337 bps, 15 haplotypes, 15 polymorphics sites, haplotype diversity of h = 0.6938, and nucleotide diversity of π = 0.01486. The neutrality tests (D and Fs were not significant. The AMOVA revealed that most of the variation (58.47% was found within populations, with FST = 0.41533 (p < 0.05. Possible isolation by distance was tested and a significant correlation coefficient (r = 0.3486; p = 0.0040 was found using the Mantel test. The phylogenetic relationships among the 15 haplotypes indicated the existence of two distinct clades. This finding, together with the population parameters, was consistent with a pattern of genetic structuring that underpinned the genetic differentiation of the study populations in Maranhão, and was characterized by the presence of distinct lineages of Aedes aegypti.

  5. Multi-modal Aedes aegypti mosquito reduction interventions and dengue fever prevention.

    Science.gov (United States)

    Ballenger-Browning, Kara K; Elder, John P

    2009-12-01

    To systematically review the effectiveness of biological, chemical and educational dengue fever prevention programs on the reduction of entomologic indicators. Searches of PubMed, GoogleScholar, CabDirect databases and reference lists yielded over 1000 articles containing mosquito abatement interventions. Inclusion criteria were: Vector control programs targeting Aedes aegypti and Aedes albopictus mosquitoes; Studies providing pre- and post-test data. Intervention effectiveness was assessed using Mulla's formula to determine percent reductions for all studies with control groups. Twenty-one studies were reviewed. Twelve dependent variables were presented, however, the Breteau, House and Container indices were the primary measurement tools for monitoring larval populations. Behavioural methods consisting of educational campaigns and maintaining water containers to reduce the mosquito population were applied in eight studies. Eight studies involved the use of biological methods such as predatory organisms or bacteria. Finally, eight studies used chemical control techniques including insecticide sprays, larvicides, insecticide-treated materials, and cleaning water of containers with household chemicals with three studies using a combination of intervention techniques. Post-intervention reduction in entomologic indices ranged from 100% to an increase of 13.9% from baseline. Little evidence exists to support the efficacy of mosquito abatement programs owing to poor study designs and lack of congruent entomologic indices. Creation of a standard entomological index, use of clustered and randomized-controlled trials, and testing the generalizability of proven methods are recommended for future research.

  6. Aedes larval indices and the occurrence of Dengue Haemorrhagic Fever in urban community of Thanlyin Township

    Directory of Open Access Journals (Sweden)

    Thae’ Zar Chi Bo

    2016-02-01

    Full Text Available A cross-sectional study was conducted in urban community of Thanlyin Township, Yangon Region during 2014 to determine Aedes larval indices and the occurrence of Dengue Haemorrhagic Fever (DHF within past one year. A total of 327 households and 1491 members were included in the study. Aedes larval indices detected in this study were 25.7% for house index, 15.5% for container index and 48.0% for Breteau index. The occurrence of DHF among households and family members were 2.1% (95% CI: 0.9%, 4.4% and 0.6% (95% CI: 0.3%, 1.1%, respectively. The occurrence was highest among 5 to 14 years age-group. No case was reported among persons with equal or more than 60 years of age. Mortality and case fatality rates were 0% during study period. Larval positivity among households was significantly related to sufficiency of family income and number of water container they have. Surveillance and control procedures for both DHF and vector should be intensified in urban area. Awareness and participation of the community in prevention and control of DHF should also be raised. Socioeconomic status as well as proper water supply and storage should be improved in urban area.

  7. Vectors expressing chimeric Japanese encephalitis dengue 2 viruses.

    Science.gov (United States)

    Wei, Y; Wang, S; Wang, X

    2014-01-01

    Vectors based on self-replicating RNAs (replicons) of flaviviruses are becoming powerful tool for expression of heterologous genes in mammalian cells and development of novel antiviral and anticancer vaccines. We constructed two vectors expressing chimeric viruses consisting of attenuated SA14-14-2 strain of Japanese encephalitis virus (JEV) in which the PrM/M-E genes were replaced fully or partially with those of dengue 2 virus (DENV-2). These vectors, named pJED2 and pJED2-1770 were transfected to BHK-21 cells and produced chimeric viruses JED2V and JED2-1770V, respectively. The chimeric viruses could be passaged in C6/36 but not BHK-21 cells. The chimeric viruses produced in C6/36 cells CPE 4-5 days after infection and RT-PCR, sequencing, immunofluorescence assay (IFA) and Western blot analysis confirmed the chimeric nature of produced viruses. The immunogenicity of chimeric viruses in mice was proved by detecting DENV-2 E protein-specific serum IgG antibodies with neutralization titer of 10. Successful preparation of infectious clones of chimeric JEV-DENV-2 viruses showed that JEV-based expression vectors are fully functional.

  8. Effects of gamma radiation on reproductive parameters of Aedes aegypti (L.) - a dengue vector

    International Nuclear Information System (INIS)

    Shetty, Vinaya; Harini, B.P.; Shetty, N.J.; Chaubey, R.C.; Jha, S.K.

    2013-01-01

    Aedes aegypti is an important vector for dengue, dengue haemorrhagic fever and chikungunya. Such diseases have resurged in developing countries and are also emerging as clear threats for epidemic outbreaks in developed countries. The said species is one of the best-known insects from the standpoint of both basic and applied sciences. Because of its medical importance and as well emerged model organism for radiation/toxicology and biochemical studies. The purpose of the present study to evaluate the impact of various doses gamma radiation on Aedes aegypti including 1, 2, 3, 4, 6, 8, 10, 15, 20, 25, 30, 35, 40, 45 and 50 Gy on different reproductive parameters i.e. fecundity, hatchability, fertility, pupation for three generations. When the flies were exposed to 1 and 2 Gy did not show any change for the above said doses. However, changes observed in hatchability from 3 Gy onwards. Reduction in fecundity was observed after exposure to 8 Gy onwards. While considerable reduction in hatchability was observed when they are exposed to 30 to 50 Gy. Sterility increased from 5 to 98% as the dose increased from 3 to 50 Gy. Furthermore, reduction in pupation and adult emergence were observed as dose increases. Dose response curve for egg hatchability and fertility for three generations were constructed and presented. From the data, it has been shown that, radiation induced dominant lethal mutations cause cessation of development prior to egg hatchability although in some cases mortality was observed in larval or pupal stages. (author)

  9. First dengue haemorrhagic fever epidemic in the Americas, 1981: insights into the causative agent.

    Science.gov (United States)

    Rodriguez-Roche, Rosmari; Hinojosa, Yoandri; Guzman, Maria G

    2014-12-01

    Historical records describe a disease in North America that clinically resembled dengue haemorrhagic fever during the latter part of the slave-trading period. However, the dengue epidemic that occurred in Cuba in 1981 was the first laboratory-confirmed and clinically diagnosed outbreak of dengue haemorrhagic fever in the Americas. At that time, the presumed source of the dengue type 2 strain isolated during this epidemic was considered controversial, partly because of the limited sequence data and partly because the origin of the virus appeared to be southern Asia. Here, we present a molecular characterisation at the whole-genome level of the original strains isolated at different time points during the epidemic. Phylogenetic trees constructed using Bayesian methods indicated that 1981 Cuban strains group within the Asian 2 genotype. In addition, the study revealed that viral evolution occurred during the epidemic - a fact that could be related to the increasing severity from month to month. Moreover, the Cuban strains exhibited particular amino acid substitutions that differentiate them from the New Guinea C prototype strain as well as from dengue type 2 strains isolated globally.

  10. Differentiating between dengue fever and malaria using hematological parameters in endemic areas of Thailand.

    Science.gov (United States)

    Kotepui, Manas; PhunPhuech, Bhukdee; Phiwklam, Nuoil; Uthaisar, Kwuntida

    2017-03-02

    Dengue fever (DF) and malaria are the two major public health concerns in tropical countries such as Thailand. Early differentiation between dengue and malaria could help clinicians to identify patients who should be closely monitored for signs of dengue hemorrhagic fever or severe malaria. This study aims to build knowledge on diagnostic markers that are used to discriminate between the infections, which frequently occur in malaria-endemic areas, such as the ones in Thailand. A retrospective study was conducted in Phop Phra Hospital, a hospital located in the Thailand-Burma border area, a malaria-endemic area, between 2013 and 2015. In brief, data on 336 patients infected with malaria were compared to data on 347 patients infected with DF. White blood cells, neutrophil, monocyte, eosinophil, neutrophil-lymphocyte ratio, and monocyte-lymphocyte ratio were significantly lower in patients with DF compared to patients with malaria (P dengue and malaria infection. This study concluded that several hematological parameters were different for diagnosing DF and malaria. A decision tree model revealed that using neutrophils, lymphocyte, MCHC, and gender was guided to discriminate patients with dengue and malaria infection. In addition, using these markers will thus lead to early detection, diagnosis, and prompt treatment of these tropical diseases.

  11. Outbreak of viral hemorrhagic fever caused by dengue virus type 3 in Al-Mukalla, Yemen.

    Science.gov (United States)

    Madani, Tariq A; Abuelzein, El-Tayeb M E; Al-Bar, Hussein M S; Azhar, Esam I; Kao, Moujahed; Alshoeb, Haj O; Bamoosa, Alabd R

    2013-03-14

    Investigations were conducted by the authors to explore an outbreak of viral hemorrhagic fever (VHF) reported in 2010 from Al-Mukalla city, the capital of Hadramout in Yemen. From 15-17 June 2010, the outbreak investigation period, specimens were obtained within 7 days after onset of illness of 18 acutely ill patients hospitalized with VHF and 15 household asymptomatic contacts of 6 acute cases. Additionally, 189 stored sera taken from acutely ill patients with suspected VHF hospitalized in the preceding 12 months were obtained from the Ministry of Health of Yemen. Thus, a total of 222 human specimens were collected; 207 specimens from acute cases and 15 specimens from contacts. All samples were tested with RT-PCR for dengue (DENV), Alkhumra (ALKV), Rift Valley Fever (RVFV), Yellow Fever (YFV), and Chikungunya (CHIKV) viruses. Samples were also tested for DENV IgM, IgG, and NS1-antigen. Medical records of patients were reviewed and demographic, clinical, and laboratory data was collected. Of 207 patients tested, 181 (87.4%) patients were confirmed to have acute dengue with positive dengue NS1-antigen (97 patients, 46.9%) and/or IgM (163 patients, 78.7%). Of the 181 patients with confirmed dengue, 100 (55.2%) patients were IgG-positive. DENV RNA was detected in 2 (1%) patients with acute symptoms; both samples were molecularly typed as DENV type 3. No other VHF viruses were detected. For the 15 contacts tested, RT-PCR tests for the five viruses were negative, one contact was dengue IgM positive, and another one was dengue IgG positive. Of the 181 confirmed dengue patients, 120 (66.3%) patients were males and the median age was 24 years. The most common manifestations included fever (100%), headache (94.5%), backache (93.4%), malaise (88.4%), arthralgia (85.1%), myalgia (82.3%), bone pain (77.9%), and leukopenia (76.2%). Two (1.1%) patients died. DENV-3 was confirmed to be the cause of an outbreak of VHF in Al-Mukalla. It is important to use both IgM and NS1-antigen

  12. Dengue fever and Aedes aegypti risk in the Galápagos Islands, Ecuador

    OpenAIRE

    Lippi, Catherine; Ibarra, Anna; Waggoner, Egan; León, Renato; Ortega, Fernando; B, Marilyn; Borbor-Cordova, Mercy; Ryan, Sadie; Nightingale, Ryan

    2017-01-01

    Introduction: Dengue fever is an emerging infectious disease in the Galápagos Islands of Ecuador, with the first cases reported in 2002 and periodic outbreaks since then. Here we report the results of a pilot study conducted in two cities in 2014: Puerto Ayora (PA) on Santa Cruz Island, and Puerto Baquerizo Moreno (PB) on Santa Cristobal Island. The aims of this study were to assess the social-ecological risk factors associated with dengue and mosquito presence at the household level. Methods...

  13. Outbreak of viral hemorrhagic fever caused by dengue virus type 3 in Al-Mukalla, Yemen

    Science.gov (United States)

    2013-01-01

    Background Investigations were conducted by the authors to explore an outbreak of viral hemorrhagic fever (VHF) reported in 2010 from Al-Mukalla city, the capital of Hadramout in Yemen. Methods From 15–17 June 2010, the outbreak investigation period, specimens were obtained within 7 days after onset of illness of 18 acutely ill patients hospitalized with VHF and 15 household asymptomatic contacts of 6 acute cases. Additionally, 189 stored sera taken from acutely ill patients with suspected VHF hospitalized in the preceding 12 months were obtained from the Ministry of Health of Yemen. Thus, a total of 222 human specimens were collected; 207 specimens from acute cases and 15 specimens from contacts. All samples were tested with RT-PCR for dengue (DENV), Alkhumra (ALKV), Rift Valley Fever (RVFV), Yellow Fever (YFV), and Chikungunya (CHIKV) viruses. Samples were also tested for DENV IgM, IgG, and NS1-antigen. Medical records of patients were reviewed and demographic, clinical, and laboratory data was collected. Results Of 207 patients tested, 181 (87.4%) patients were confirmed to have acute dengue with positive dengue NS1-antigen (97 patients, 46.9%) and/or IgM (163 patients, 78.7%). Of the 181 patients with confirmed dengue, 100 (55.2%) patients were IgG-positive. DENV RNA was detected in 2 (1%) patients with acute symptoms; both samples were molecularly typed as DENV type 3. No other VHF viruses were detected. For the 15 contacts tested, RT-PCR tests for the five viruses were negative, one contact was dengue IgM positive, and another one was dengue IgG positive. Of the 181 confirmed dengue patients, 120 (66.3%) patients were males and the median age was 24 years. The most common manifestations included fever (100%), headache (94.5%), backache (93.4%), malaise (88.4%), arthralgia (85.1%), myalgia (82.3%), bone pain (77.9%), and leukopenia (76.2%). Two (1.1%) patients died. Conclusions DENV-3 was confirmed to be the cause of an outbreak of VHF in Al

  14. Dengue Fever Seroprevalence and Risk Factors, Texas-Mexico Border, 2004

    Centers for Disease Control (CDC) Podcasts

    2007-11-01

    Dengue fever is both endemic and underrecognized along a section of the southern Texas–Mexico border, and low income is a primary risk factor for infection. As part of a special section on Global Poverty and Human Development, Dr. Joan Marie Brunkard discusses a dengue seroprevalence survey in this region and what can be done to help prevent infection and to identify and treat those who are infected.  Created: 11/1/2007 by Emerging Infectious Diseases.   Date Released: 1/24/2008.

  15. Effects of weather factors on dengue fever incidence and implications for interventions in Cambodia

    Directory of Open Access Journals (Sweden)

    Youngjo Choi

    2016-03-01

    Full Text Available Abstract Background Dengue viruses and their mosquito vectors are sensitive to their environment. Temperature, rainfall and humidity have well-defined roles in the transmission cycle. Therefore changes in these conditions may contribute to increasing incidence. The aim of this study was to examine the relationship between weather factors and dengue incidence in three provinces in Cambodia, in order to strengthen the evidence basis of dengue control strategies in this high-burden country. Methods We developed negative binomial models using monthly average maximum, minimum, mean temperatures and monthly cumulative rainfall over the period from January 1998 to December 2012. We adopted piecewise linear functions to estimate the incidence rate ratio (IRR between dengue incidence and weather factors for simplicity in interpreting the coefficients. We estimated the values of parameters below cut-points defined in terms of the results of sensitivity tests over a 0-3 month lagged period. Results Mean temperature was significantly associated with dengue incidence in all three provinces, but incidence did not correlate well with maximum temperature in Banteay Meanchey, nor with minimum temperature in Kampong Thom at a lag of three months in the negative binomial model. The monthly cumulative rainfall influence on the dengue incidence was significant in all three provinces, but not consistently over a 0-3 month lagged period. Rainfall significantly affected the dengue incidence at a lag of 0 to 3 months in Siem Reap, but it did not have an impact at a lag of 2 to 3 months in Banteay Meanchey, nor at a lag of 2 months in Kampong Thom. Conclusions The association between dengue incidence and weather factors also apparently varies by locality, suggesting that a prospective dengue early warning system would likely be best implemented at a local or regional scale, rather than nation-wide in Cambodia. Such spatial down-scaling would also enable dengue control

  16. Oviposition Site Selection by the Dengue Vector Aedes aegypti and Its Implications for Dengue Control

    Science.gov (United States)

    Wong, Jacklyn; Stoddard, Steven T.; Astete, Helvio; Morrison, Amy C.; Scott, Thomas W.

    2011-01-01

    Background Because no dengue vaccine or antiviral therapy is commercially available, controlling the primary mosquito vector, Aedes aegypti, is currently the only means to prevent dengue outbreaks. Traditional models of Ae. aegypti assume that population dynamics are regulated by density-dependent larval competition for food and little affected by oviposition behavior. Due to direct impacts on offspring survival and development, however, mosquito choice in oviposition site can have important consequences for population regulation that should be taken into account when designing vector control programs. Methodology/Principal Findings We examined oviposition patterns by Ae. aegypti among 591 naturally occurring containers and a set of experimental containers in Iquitos, Peru. Using larval starvation bioassays as an indirect measure of container food content, we assessed whether females select containers with the most food for their offspring. Our data indicate that choice of egg-laying site is influenced by conspecific larvae and pupae, container fill method, container size, lid, and sun exposure. Although larval food positively influenced oviposition, our results did not support the hypothesis that females act primarily to maximize food for larvae. Females were most strongly attracted to sites containing immature conspecifics, even when potential competitors for their progeny were present in abundance. Conclusion/Significance Due to strong conspecific attraction, egg-laying behavior may contribute more to regulating Ae. aegypti populations than previously thought. If highly infested containers are targeted for removal or larvicide application, females that would have preferentially oviposited in those sites may instead distribute their eggs among other suitable, previously unoccupied containers. Strategies that kill mosquitoes late in their development (i.e., insect growth regulators that kill pupae rather than larvae) will enhance vector control by creating

  17. Tracking the return of Aedes aegypti to Brazil, the major vector of the dengue, chikungunya and Zika viruses.

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    Kotsakiozi, Panayiota; Gloria-Soria, Andrea; Caccone, Adalgisa; Evans, Benjamin; Schama, Renata; Martins, Ademir Jesus; Powell, Jeffrey R

    2017-07-01

    Aedes aegypti, commonly known as "the yellow fever mosquito", is of great medical concern today primarily as the major vector of dengue, chikungunya and Zika viruses, although yellow fever remains a serious health concern in some regions. The history of Ae. aegypti in Brazil is of particular interest because the country was subjected to a well-documented eradication program during 1940s-1950s. After cessation of the campaign, the mosquito quickly re-established in the early 1970s with several dengue outbreaks reported during the last 30 years. Brazil can be considered the country suffering the most from the yellow fever mosquito, given the high number of dengue, chikungunya and Zika cases reported in the country, after having once been declared "free of Ae. aegypti". We used 12 microsatellite markers to infer the genetic structure of Brazilian Ae. aegypti populations, genetic variability, genetic affinities with neighboring geographic areas, and the timing of their arrival and spread. This enabled us to reconstruct their recent history and evaluate whether the reappearance in Brazil was the result of re-invasion from neighboring non-eradicated areas or re-emergence from local refugia surviving the eradication program. Our results indicate a genetic break separating the northern and southern Brazilian Ae. aegypti populations, with further genetic differentiation within each cluster, especially in southern Brazil. Based on our results, re-invasions from non-eradicated regions are the most likely scenario for the reappearance of Ae. aegypti in Brazil. While populations in the northern cluster are likely to have descended from Venezuela populations as early as the 1970s, southern populations seem to have derived more recently from northern Brazilian areas. Possible entry points are also revealed within both southern and northern clusters that could inform strategies to control and monitor this important arbovirus vector.

  18. Tracking the return of Aedes aegypti to Brazil, the major vector of the dengue, chikungunya and Zika viruses.

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    Panayiota Kotsakiozi

    2017-07-01

    Full Text Available Aedes aegypti, commonly known as "the yellow fever mosquito", is of great medical concern today primarily as the major vector of dengue, chikungunya and Zika viruses, although yellow fever remains a serious health concern in some regions. The history of Ae. aegypti in Brazil is of particular interest because the country was subjected to a well-documented eradication program during 1940s-1950s. After cessation of the campaign, the mosquito quickly re-established in the early 1970s with several dengue outbreaks reported during the last 30 years. Brazil can be considered the country suffering the most from the yellow fever mosquito, given the high number of dengue, chikungunya and Zika cases reported in the country, after having once been declared "free of Ae. aegypti".We used 12 microsatellite markers to infer the genetic structure of Brazilian Ae. aegypti populations, genetic variability, genetic affinities with neighboring geographic areas, and the timing of their arrival and spread. This enabled us to reconstruct their recent history and evaluate whether the reappearance in Brazil was the result of re-invasion from neighboring non-eradicated areas or re-emergence from local refugia surviving the eradication program. Our results indicate a genetic break separating the northern and southern Brazilian Ae. aegypti populations, with further genetic differentiation within each cluster, especially in southern Brazil.Based on our results, re-invasions from non-eradicated regions are the most likely scenario for the reappearance of Ae. aegypti in Brazil. While populations in the northern cluster are likely to have descended from Venezuela populations as early as the 1970s, southern populations seem to have derived more recently from northern Brazilian areas. Possible entry points are also revealed within both southern and northern clusters that could inform strategies to control and monitor this important arbovirus vector.

  19. The early use of break-bone fever (Quebranta huesos, 1771) and dengue (1801) in Spanish.

    Science.gov (United States)

    Rigau-Pérez, J G

    1998-08-01

    The appellation of break-bone fever for dengue is attributed to the popular name given to the disease in the first described epidemic of an illness that is clinically compatible with dengue in Philadelphia in 1780. The origin of the word dengue as the name of an illness is currently attributed to the Swahili phrase Ka dinga pepo, thought to have crossed from Africa to the Caribbean in 1827; in Cuba this phrase was popularly identified with the Spanish word dengue. This article presents documents from Spanish archives that indicate the use of quebranta huesos (break-bone) by a physician in Puerto Rico to describe a febrile illness in 1771, and the use of the term dengue by the Queen of Spain in 1801 to describe an acute febrile illness with bone and joint pains, hemorrhage, and jaundice. These texts are evidence of a more generalized use of the term break-bone than previously recognized, and conversely, the specifically Spanish origin of dengue as the name for an illness.

  20. Self-affinity in the dengue fever time series

    Science.gov (United States)

    Azevedo, S. M.; Saba, H.; Miranda, J. G. V.; Filho, A. S. Nascimento; Moret, M. A.

    2016-06-01

    Dengue is a complex public health problem that is common in tropical and subtropical regions. This disease has risen substantially in the last three decades, and the physical symptoms depict the self-affine behavior of the occurrences of reported dengue cases in Bahia, Brazil. This study uses detrended fluctuation analysis (DFA) to verify the scale behavior in a time series of dengue cases and to evaluate the long-range correlations that are characterized by the power law α exponent for different cities in Bahia, Brazil. The scaling exponent (α) presents different long-range correlations, i.e. uncorrelated, anti-persistent, persistent and diffusive behaviors. The long-range correlations highlight the complex behavior of the time series of this disease. The findings show that there are two distinct types of scale behavior. In the first behavior, the time series presents a persistent α exponent for a one-month period. For large periods, the time series signal approaches subdiffusive behavior. The hypothesis of the long-range correlations in the time series of the occurrences of reported dengue cases was validated. The observed self-affinity is useful as a forecasting tool for future periods through extrapolation of the α exponent behavior. This complex system has a higher predictability in a relatively short time (approximately one month), and it suggests a new tool in epidemiological control strategies. However, predictions for large periods using DFA are hidden by the subdiffusive behavior.

  1. Climate Change and Aedes Vectors: 21st Century Projections for Dengue Transmission in Europe

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    Jing Liu-Helmersson

    2016-05-01

    Full Text Available Warming temperatures may increase the geographic spread of vector-borne diseases into temperate areas. Although a tropical mosquito-borne viral disease, a dengue outbreak occurred in Madeira, Portugal, in 2012; the first in Europe since 1920s. This outbreak emphasizes the potential for dengue re-emergence in Europe given changing climates. We present estimates of dengue epidemic potential using vectorial capacity (VC based on historic and projected temperature (1901–2099. VC indicates the vectors' ability to spread disease among humans. We calculated temperature-dependent VC for Europe, highlighting 10 European cities and three non-European reference cities. Compared with the tropics, Europe shows pronounced seasonality and geographical heterogeneity. Although low, VC during summer is currently sufficient for dengue outbreaks in Southern Europe to commence–if sufficient vector populations (either Ae. aegypti and Ae. albopictus were active and virus were introduced. Under various climate change scenarios, the seasonal peak and time window for dengue epidemic potential increases during the 21st century. Our study maps dengue epidemic potential in Europe and identifies seasonal time windows when major cities are most conducive for dengue transmission from 1901 to 2099. Our findings illustrate, that besides vector control, mitigating greenhouse gas emissions crucially reduces the future epidemic potential of dengue in Europe.

  2. [Analysis of clinical characteristics of the 12 cases of neonatal dengue fever in Guangzhou in 2014 and literatures review].

    Science.gov (United States)

    Tan, Limei; Wang, Junping; Zeng, Fansen; Zhang, Yong; Fang, Chunxiao; Nie, Chuan; Xu, Yi; Yang, Jie

    2015-12-01

    To explore the clinical manifestations and laboratory examination characteristics of neonatal dengue fever. A retrospective analysis of 12 cases of neonatal dengue fever treated in the Guangdong Women and Children's Hospital and Guangzhou Women and Children's Medical Center was conducted, and related literature was reviewed. Twelve cases of neonatal dengue fever included 9 males and 3 females; their age was 30 min after birth to 29 d, the age of onset was 30 min-24 d. (1) CLINICAL FEATURES: fever was present in 11 cases, rash in 6 cases, bleeding in 1 case, jaundice in 5 cases, cough in 1 case, coagulopathy in 2 cases. (2) Mothers' perinatal conditions: 7 mothers were confirmed to have dengue fever, 2 mothers had suspected dengue fever, and in 3 mothers the dengue fever was excluded. Eight mothers prenatally had fever. (3) LABORATORY TESTS: Thrombocytopenia was found in 11 cases (19×10(9)-156×10(9)/L), activated partial thromboplastin time prolonged in 11 cases (44.0-89.8 s), fibrinogen decreased in 5 cases (1.17-3.02 g/L), aspartate aminotransferase (AST) increased in 5 cases (28-78 U/L), creatine kinase (CK-MB) increased in 4 cases (13-86 U/L), hypokalemia in 1 case (2.8-5.1 mmol/L ), C- reactive protein (CRP) increased in 6 cases (0.04-46.05 mg/L). (4) Treatment and prognosis: platelet transfusion was used in 2 cases, anti-infective therapy was given to 6 cases, intravenous gamma globulin treatment was used in 5 cases, hospitalization was 4-17 d, 10 cases were cured, 2 cases were discharged after condition was improved. Literature search was performed with "neonatal dengue" as keywords at Wanfang, Weipu, and CNKI, no relevant reports were found. Pubmed search was done with "neonatal dengue" and "case report" as keywords, 15 reports were retrieved during 1990 and 2014, which reported 30 cases, all acquired the disease via vertical transmission; the main clinical manifestations were fever, rash, petechiae, anemia, jaundice, tachycardia, and hepatomegaly

  3. Dengue hemorrhagic fever and typhoid fever association based on spatial standpoint using scan statistics in DKI Jakarta

    Science.gov (United States)

    Hervind, Widyaningsih, Y.

    2017-07-01

    Concurrent infection with multiple infectious agents may occur in one patient, it appears frequently in dengue hemorrhagic fever (DHF) and typhoid fever. This paper depicted association between DHF and typhoid based on spatial point of view. Since paucity of data regarding dengue and typhoid co-infection, data that be used are the number of patients of those diseases in every district (kecamatan) in Jakarta in 2014 and 2015 obtained from Jakarta surveillance website. Poisson spatial scan statistics is used to detect DHF and typhoid hotspots area district in Jakarta separately. After obtain the hotspot, Fisher's exact test is applied to validate association between those two diseases' hotspot. The result exhibit hotspots of DHF and typhoid are located around central Jakarta. The further analysis used Poisson space-time scan statistics to reveal the hotspot in term of spatial and time. DHF and typhoid fever more likely occurr from January until May in the area which is relatively similar with pure spatial result. Preventive action could be done especially in the hotspot areas and it is required further study to observe the causes based on characteristics of the hotspot area.

  4. CLINICAL AND HEMATOLOGICAL PROFILE OF PATIENTS WITH DENGUE FEVER AT A TERTIARY CARE HOSPITAL – AN OBSERVATIONAL STUDY

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    Vishal Vishnu Tewari

    2018-03-01

    Full Text Available Abstract Background: Dengue is a major health issue with seasonal rise in dengue fever cases imposing an additional burden on hospitals, necessitating bolstering of services in the emergency department, laboratory with creation of additional dengue fever wards. Objectives: To study the clinical and hematological profile of dengue fever cases presenting to a hospital. Methods: Patients with fever and other signs of dengue with either positive NS1 antigen test or IgM or IgG antibody were included. Age, gender, clinical presentation, platelet count and hematocrit were noted and patients classified as dengue fever (DF, dengue hemorrhagic fever (DHF or dengue shock syndrome (DSS. Duration of hospitalization, bleeding manifestations, requirement for platelet component support and mortality were recorded. Results: There were 443 adults and 57 children between 6 months to 77 year age. NS1 was positive in 115 patients (23%. Fever (99.8% and severe bodyache (97.4% were the commonest presentation. DF was seen in 484 (96.8 %, DHF in 10 (2% and DSS in 6 cases (1.2%. OPD treatment was needed in 412 (82% and hospitalization in 88 (18%. Intravenous fluid resuscitation was needed in 16 (3.2% patients. Thrombocytopenia was seen in 335 (67% patients at presentation. Platelet transfusion was needed in 46 (9.2%. PRC transfusion was given in 3 patients with DF and 10 of DHF. Death occurred in 03 DSS and 2 DHF patients. Conclusions: Majority of DF cases can be managed on OPD basis. DHF and DSS carry high mortality. Hospitals can analyze annual data for resource allocation for capacity expansion.

  5. Potential impacts of climate variability on dengue hemorrhagic fever in Honduras, 2010.

    Science.gov (United States)

    Zambrano, L I; Sevilla, C; Reyes-García, S Z; Sierra, M; Kafati, R; Rodriguez-Morales, A J; Mattar, S

    2012-12-01

    Climate change and variability are affecting human health and disease direct or indirectly through many mechanisms. Dengue is one of those diseases that is strongly influenced by climate variability; however its study in Central America has been poorly approached. In this study, we assessed potential associations between macroclimatic and microclimatic variation and dengue hemorrhagic fever (DHF) cases in the main hospital of Honduras during 2010. In this year, 3,353 cases of DHF were reported in the Hospital Escuela, Tegucigalpa. Climatic periods marked a difference of 158% in the mean incidence of cases, from El Niño weeks (-99% of cases below the mean incidence) to La Niña months (+59% of cases above it) (pHonduras. However, it is necessary to extend these studies in this and other countries in the Central America region, because these models can be applied for surveillance as well as for prediction of dengue.

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

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    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. Copyright © 2012 Elsevier Ltd. All rights reserved.

  7. Dengue fever Potential Area at Pademangan Barat Sub District, North Jakarta

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    Tri E. B. Soesilo

    2011-06-01

    Full Text Available Dengue hemorrhagic fever is an infectious disease that contagious by Aedes aegypti mosquito’s bites. Anybody could infectious by this illness, without differentiate their sex, age, social status, and economic status as well. Nevertheless, at slum area, where mosquito’s larva is easy to find, the number of infectious people is presuming high. By using primary data and analyze with geography information system (GIS, the study found that the number of infectious people of dengue fever do not have any positive correlation with larva amount, that was monitored through clean water in the surrounding neighborhood area. The number of infectious people have correlation with the dirty areas that caused by the piling of used articles and inundate area. Gender and age do not have any influence with the number of infectious people.

  8. 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 kit for dengue if the kit was available compared to those with higher perceived barriers to dengue prevention (level of barriers 6-10). Participants with a lower total 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

  9. FACTORS PREDICTING MORBIDITY IN PATIENTS WITH DENGUE FEVER IN A TERTIARY CARE HOSPITAL

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    Muhammad Imran Hasan Khan

    2013-02-01

    Full Text Available Introduction: Dengue virus (DENV affects over half the world’s population in 112 countries, and dengue fever (DF is the second largest arthropod borne infectious global hazard after malaria with complications like Dengue Hemorrhagic Fever (DHF and Dengue Shock Syndrome (DSS accounting for significant morbidity and mortality world over. Pakistan is significantly affected with DENV infection and to-date no study identifying risk factors associated with complications of DF has been done. Methods: 997 confirmed cases of DF were collected in a tertiary care hospital in Lahore, Pakistan and their clinical and biochemical data were collected. Univariate, multivariate and logistics regression analysis was performed to identify risk factors associated with development of DHF and DSS. Results: Bleeding OR 70.7 (CI 38.4-129.9, deranged liver function test OR 1.9 (CI 0.97-0.99, platelet count on admission less than 50,000 x109/L OR 0.16 (CI 0.13-0.19, presence of urinary red blood cells OR 1.4 (CI 0.179-0.900 and presence of urinary protein OR 1.1 (CI 0.191-0.974 were related to development of DHF and DSS.

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

    Science.gov (United States)

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

    2015-02-01

    Uruguay is located at the southern border of Aedes aegypti distribution on the South American sub-continent. The reported dengue cases in the country are all imported from surrounding countries. One of the cities at higher risk of local dengue transmission is Salto, a border city with heavy traffic from dengue endemic areas. We completed an intervention study using a cluster randomized trial design in 20 randomly selected 'clusters' in Salto. The clusters were located in neighborhoods of differing geography and economic, cultural and social aspects. Entomological surveys were carried out to measure the impact of the intervention on vector densities. Through participatory processes of all stakeholders, an appropriate ecosystem management intervention was defined. Residents collected the abundant small water holding containers and the Ministry of Public Health and the Municipality of Salto were responsible for collecting and eliminating them. Additional vector breeding places were large water tanks; they were either altered so that they could not hold water any more or covered so that oviposition by mosquitoes could not take place. The response from the community and national programme managers was encouraging. The intervention evidenced opportunities for cost savings and reducing dengue vector densities (although not to statistically significant levels). The observed low vector density limits the potential reduction due to the intervention. A larger sample size is needed to obtain a statistically significant difference. © The author 2015. The World Health Organization has granted Oxford University Press permission for the reproduction of this article.

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

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    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.

  12. Pyrethroid Susceptibility Has Been Maintained in the Dengue Vector, Aedes aegypti (Diptera: Culicidae), in Queensland, Australia.

    Science.gov (United States)

    Endersby-Harshman, Nancy M; Wuliandari, Juli Rochmijati; Harshman, Lawrence G; Frohn, Verena; Johnson, Brian J; Ritchie, Scott A; Hoffmann, Ary A

    2017-11-07

    Although pesticide resistance is common in insect vectors of human diseases, the evolution of resistance might be delayed if management practices are adopted that limit selection of resistance alleles. Outbreaks of dengue fever have occurred in Queensland, Australia, since the late 1800s, leading to ongoing attempts to control the mosquito vector, Aedes aegypti (L.). Since the 1990s, pyrethroid insecticides have been used for this purpose, but have been applied in a strategic manner with a variety of delivery methods including indoor residual spraying, lethal ovitraps, and use of insect growth regulators as larvicides. Separate selection experiments on mosquitoes from Queensland using Type I and Type II pyrethroids did not produce resistant lines of Ae. aegypti, and bioassays of field material from Queensland showed only weak tolerance in comparison with a susceptible line. There was no evidence of knockdown resistance (kdr) mutations in Ae. aegypti from Queensland, in stark contrast to the situation in nearby southeast Asia. We suspect that careful management of pyrethroid insecticide use combined with surveillance and interception of exotic incursions has helped to maintain pyrethroid (and particularly kdr-based) susceptibility in Ae. aegypti in Australia. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  13. Dengue Hemorrhagic Fever at 60 Years: Early Evolution of Concepts of Causation and Treatment.

    Science.gov (United States)

    Halstead, Scott B; Cohen, Sanford N

    2015-09-01

    During the decade of the 1960s, the epidemiology of a new dengue disease, dengue hemorrhagic fever and dengue shock syndrome (DHF/DSS), was described by collaborative research performed by Thai scientists from many institutions and by workers at the U.S. Army's SEATO Medical Research Laboratory in Bangkok, Thailand. Careful clinical and physiological studies provided the initial description of DSS. DSS cases were caused by each of the four dengue viruses (DENV) and not chikungunya (CHIK) virus or DENV 5 and 6, were associated with a secondary-type dengue antibody response in children over the age of 1 year, were associated with a primary antibody response in infants less than 1 year old whose mothers had neutralizing antibodies to all four DENV, were associated more frequently with secondary DENV 2 infections than those due to DENV 1 and 3, and were more common in females than males over the age of 3 years. Robust laboratory methods for growth and recovery of DENV in tissue cultures were introduced. In addition, life-saving principles of fluid and plasma protein resuscitation of hypovolemia were described. Most epidemiological observations made during the decade of the 1960s have been confirmed in the succeeding 45 years. Much contemporary research on pathogenesis fails to address the two distinct immunological antecedents of DHF/DSS. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  14. CORRELATION OF ULTRASOUND (USG FINDINGS WITH SEROLOGICAL TESTS IN DENGUE FEVER

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    Dayanand

    2016-02-01

    Full Text Available INTRODUCTION Dengue is an endemic and epidemic disease of the tropical and subtropical regions. Between September & October 2012, there was an established outbreak of dengue in Hoskote, near Bangalore. Dengue results in serositis, which can be imaged by ultrasonography. OBJECTIVE To correlate the USG findings with the serological tests in paediatric and adult patients. MATERIALS AND METHODS 110 patients with clinical suspicion of dengue fever during the above period underwent serological tests-NS1, IgM and IgG and were evaluated with USG of the abdomen and thorax. The USG findings were correlated with serological tests. RESULTS 67 Patients were seropositive, 43 were seronegative. The USG findings in seropositive paediatric patients (n=32 and adult patients (n=35 respectively were gall bladder (GB wall edema-27 & 31, hepatomegaly-12 &14, ascites-16 & 12, splenomegaly- 15 & 9, right pleural effusion-14 & 13, left and bilateral pleural effusion-7 & 5. CONCLUSION In our study GB wall edema significantly correlated with seropositivity (p value=0.032. Thus ultrasound is an efficient screening tool in a case of dengue outbreak.

  15. 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.

  16. Dengue Fever in American Military Personnel in the Philippines: Clinical Observations on Hospitalized Patients during a 1984 Epidemic

    Science.gov (United States)

    1989-03-01

    the mean maximum temperature was Hypotenson 15 (62.5) 102.0 + 1.3 F. A "saddle back" or dip- Rash (Non- Petechial ) 13 (54.2) hasic fever pattern was not...DENGUE FEVER IN AMERICAN MILITARY PERSONNEL IN THE PHILIPPINES: CLINICAL OBSERVATIONS ON HOSPITALIZED PATIENS DURING A 1984 EPIDEMIC C.G. Hayes, T.F...Accession Tr~I Jti ti DENGUE FEVER IN AMERICAN MILITARY PERSONNEL IN THE PHILIPPINES: CLINICAL OBSERVATIONS ON HOSPITALIZED PATIENTS DURING A 1984

  17. Autoimmunity in dengue pathogenesis

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    Shu-Wen Wan

    2013-01-01

    Full Text Available Dengue is one of the most important vector-borne viral diseases. With climate change and the convenience of travel, dengue is spreading beyond its usual tropical and subtropical boundaries. Infection with dengue virus (DENV causes diseases ranging widely in severity, from self-limited dengue fever to life-threatening dengue hemorrhagic fever and dengue shock syndrome. Vascular leakage, thrombocytopenia, and hemorrhage are the major clinical manifestations associated with severe DENV infection, yet the mechanisms remain unclear. Besides the direct effects of the virus, immunopathogenesis is also involved in the development of dengue disease. Antibody-dependent enhancement increases the efficiency of virus infection and may suppress type I interferon-mediated antiviral responses. Aberrant activation of T cells and overproduction of soluble factors cause an increase in vascular permeability. DENV-induced autoantibodies against endothelial cells, platelets, and coagulatory molecules lead to their abnormal activation or dysfunction. Molecular mimicry between DENV proteins and host proteins may explain the cross-reactivity of DENV-induced autoantibodies. Although no licensed dengue vaccine is yet available, several vaccine candidates are under development. For the development of a safe and effective dengue vaccine, the immunopathogenic complications of dengue disease need to be considered.

  18. Assessment of risk of dengue and yellow fever virus transmission in three major Kenyan cities based on Stegomyia indices

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    Tchouassi, David P.; Bastos, Armanda D. S.; Sang, Rosemary

    2017-01-01

    Dengue (DEN) and yellow fever (YF) are re-emerging in East Africa, with contributing drivers to this trend being unplanned urbanization and increasingly adaptable anthropophilic Aedes (Stegomyia) vectors. Entomological risk assessment of these diseases remains scarce for much of East Africa and Kenya even in the dengue fever-prone urban coastal areas. Focusing on major cities of Kenya, we compared DEN and YF risk in Kilifi County (DEN-outbreak-prone), and Kisumu and Nairobi Counties (no documented DEN outbreaks). We surveyed water-holding containers for mosquito immature (larvae/pupae) indoors and outdoors from selected houses during the long rains, short rains and dry seasons (100 houses/season) in each County from October 2014-June 2016. House index (HI), Breteau index (BI) and Container index (CI) estimates based on Aedes (Stegomyia) immature infestations were compared by city and season. Aedes aegypti and Aedes bromeliae were the main Stegomyia species with significantly more positive houses outdoors (212) than indoors (88) (n = 900) (χ2 = 60.52, P < 0.0001). Overall, Ae. aegypti estimates of HI (17.3 vs 11.3) and BI (81.6 vs 87.7) were higher in Kilifi and Kisumu, respectively, than in Nairobi (HI, 0.3; BI,13). However, CI was highest in Kisumu (33.1), followed by Kilifi (15.1) then Nairobi (5.1). Aedes bromeliae indices were highest in Kilifi, followed by Kisumu, then Nairobi with HI (4.3, 0.3, 0); BI (21.3, 7, 0.7) and CI (3.3, 3.3, 0.3), at the respective sites. HI and BI for both species were highest in the long rains, compared to the short rains and dry seasons. We found strong positive correlations between the BI and CI, and BI and HI for Ae. aegypti, with the most productive container types being jerricans, drums, used/discarded containers and tyres. On the basis of established vector index thresholds, our findings suggest low-to-medium risk levels for urban YF and high DEN risk for Kilifi and Kisumu, whereas for Nairobi YF risk was low while DEN risk

  19. Assessment of risk of dengue and yellow fever virus transmission in three major Kenyan cities based on Stegomyia indices.

    Directory of Open Access Journals (Sweden)

    Sheila B Agha

    2017-08-01

    Full Text Available Dengue (DEN and yellow fever (YF are re-emerging in East Africa, with contributing drivers to this trend being unplanned urbanization and increasingly adaptable anthropophilic Aedes (Stegomyia vectors. Entomological risk assessment of these diseases remains scarce for much of East Africa and Kenya even in the dengue fever-prone urban coastal areas. Focusing on major cities of Kenya, we compared DEN and YF risk in Kilifi County (DEN-outbreak-prone, and Kisumu and Nairobi Counties (no documented DEN outbreaks. We surveyed water-holding containers for mosquito immature (larvae/pupae indoors and outdoors from selected houses during the long rains, short rains and dry seasons (100 houses/season in each County from October 2014-June 2016. House index (HI, Breteau index (BI and Container index (CI estimates based on Aedes (Stegomyia immature infestations were compared by city and season. Aedes aegypti and Aedes bromeliae were the main Stegomyia species with significantly more positive houses outdoors (212 than indoors (88 (n = 900 (χ2 = 60.52, P < 0.0001. Overall, Ae. aegypti estimates of HI (17.3 vs 11.3 and BI (81.6 vs 87.7 were higher in Kilifi and Kisumu, respectively, than in Nairobi (HI, 0.3; BI,13. However, CI was highest in Kisumu (33.1, followed by Kilifi (15.1 then Nairobi (5.1. Aedes bromeliae indices were highest in Kilifi, followed by Kisumu, then Nairobi with HI (4.3, 0.3, 0; BI (21.3, 7, 0.7 and CI (3.3, 3.3, 0.3, at the respective sites. HI and BI for both species were highest in the long rains, compared to the short rains and dry seasons. We found strong positive correlations between the BI and CI, and BI and HI for Ae. aegypti, with the most productive container types being jerricans, drums, used/discarded containers and tyres. On the basis of established vector index thresholds, our findings suggest low-to-medium risk levels for urban YF and high DEN risk for Kilifi and Kisumu, whereas for Nairobi YF risk was low while DEN risk

  20. Identification of Dengue and Chikungunya Cases Among Suspected Cases of Yellow Fever in the Democratic Republic of the Congo.

    Science.gov (United States)

    Makiala-Mandanda, Sheila; Ahuka-Mundeke, Steve; Abbate, Jessica L; Pukuta-Simbu, Elisabeth; Nsio-Mbeta, Justus; Berthet, Nicolas; Leroy, Eric Maurice; Becquart, Pierre; Muyembe-Tamfum, Jean-Jacques

    2018-05-16

    For more than 95% of acute febrile jaundice cases identified through surveillance for yellow fever, a reemerging arthropod-borne viral disease, no etiological exploration is ever done. The aim of this study was to test for other arthropod-borne viruses that can induce the same symptoms in patients enrolled in the yellow fever surveillance in the Democratic Republic of the Congo (DRC). Of 652 patients included in the surveillance of yellow fever in DRC from January 2003 to January 2012, 453 patients that tested negative for yellow fever virus (YFV) immunoglobulin M (IgM) antibodies were selected for the study. Real-time polymerase chain reaction was performed for the detection of dengue, West Nile, Chikungunya, O'nyong-nyong, Rift Valley fever, Zika, and YFV. The average age of patients was 22.1 years. We reported 16 cases (3.5%; confidence interval [CI]: 0.8-5.2) of dengue (serotypes 1 and 2) and 2 cases (0.4%; CI: 0.0-1.0) of Chikungunya. Three patients were co-infected with the two serotypes of dengue virus. Three cases of dengue were found in early July 2010 from the city of Titule (Oriental province) during a laboratory-confirmed outbreak of yellow fever, suggesting simultaneous circulation of dengue and yellow fever viruses. This study showed that dengue and Chikungunya viruses are potential causes of acute febrile jaundice in the DRC and highlights the need to consider dengue and Chikungunya diagnosis in the integrated disease surveillance and response program in the DRC. A prospective study is necessary to establish the epidemiology of these diseases.

  1. Evaluation of the national Notifiable Diseases Surveillance System for dengue fever in Taiwan, 2010-2012.

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    Caoimhe McKerr

    2015-03-01

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

  2. Spatio-temporal modelling of dengue fever incidence in Malaysia

    Science.gov (United States)

    Che-Him, Norziha; Ghazali Kamardan, M.; Saifullah Rusiman, Mohd; Sufahani, Suliadi; Mohamad, Mahathir; @ Kamariah Kamaruddin, Nafisah

    2018-04-01

    Previous studies reported significant relationship between dengue incidence rate (DIR) and both climatic and non-climatic factors. Therefore, this study proposes a generalised additive model (GAM) framework for dengue risk in Malaysia by using both climatic and non-climatic factors. The data used is monthly DIR for 12 states of Malaysia from 2001 to 2009. In this study, we considered an annual trend, seasonal effects, population, population density and lagged DIR, rainfall, temperature, number of rainy days and El Niño-Southern Oscillation (ENSO). The population density is found to be positively related to monthly DIR. There are generally weak relationships between monthly DIR and climate variables. A negative binomial GAM shows that there are statistically significant relationships between DIR with climatic and non-climatic factors. These include mean rainfall and temperature, the number of rainy days, sea surface temperature and the interaction between mean temperature (lag 1 month) and sea surface temperature (lag 6 months). These also apply to DIR (lag 3 months) and population density.

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

    Science.gov (United States)

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

    2005-09-01

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

  4. Clinical and laboratory profile of dengue fever patients admitted in combined military hospital rawalpindi in year 2015

    International Nuclear Information System (INIS)

    Rehman, M. M. U.; Zakaria, M.; Mustafvi, S. A.

    2017-01-01

    Objective: The purpose of this study was to determine the pattern of clinical presentations, haematological and biochemical abnormalities, and outcome of dengue fever patients admitted in Combined Military Hospital (CMH) Rawalpindi in year 2015. Study Design: A descriptive cross sectional study. Place and Duration of Study: Department of Medicine, CMH Rawalpindi, from January 2015 to December 2015. Material and Methods: Patients meeting the inclusion criteria were admitted at CMH Rawalpindi and blood serology was done to confirm the diagnosis of dengue fever. Cases with positive dengue serology were included in the study. Clinical symptoms, signs, investigations and outcome of these patients were recorded on a proforma. Blood samples were taken for analysis. Chest X-Ray and ultrasound abdomen were done on required basis. Results: Out of forty confirmed cases of dengue fever, there were 25 (62.5 percent) males and 15 (37.5 percent) females. Mean age was 40 years. There were 39 cases (97.5 percent) of dengue fever and one case (2.5 percent) of dengue shock syndrome.There was no case of dengue haemorrhagic syndrome. Maximum cases were seen in the month of October 2015.The clinical features noted were: headache and myalgias 62.5 percent, chills and rigors 57.5 percent, retro-orbital pain 42.5 percent, vomiting 35.0 percent, pruritus 27 percent, skin rash 20 percent, abdominal pain 20 percent, diarrhoea 10 percent, bleeding 2.5 percent, ascites and pleural effusion 2.5 percent, and hepatomegaly 15 percent. The laboratory findings were: leucopenia 85 percent and thrombocytopenia 92.5 percent. Serum alanine transaminase (ALT), urea, and creatinine were raised in 30 percent, 2.5 percent and 7.5 percent cases respectively. Mortality was 2.5 percent. Conclusion: This study showed that patients admitted to CMH hospital had a milder presentation of dengue fever in the year 2015. (author)

  5. Human and entomological surveillance of West Nile fever, dengue and chikungunya in Veneto Region, Italy, 2010-2012.

    Science.gov (United States)

    Gobbi, Federico; Capelli, Gioia; Angheben, Andrea; Giobbia, Mario; Conforto, Mario; Franzetti, Marzia; Cattelan, Anna Maria; Raise, Enzo; Rovere, Pierangelo; Mulatti, Paolo; Montarsi, Fabrizio; Drago, Andrea; Barzon, Luisa; Napoletano, Giuseppina; Zanella, Francesca; Pozza, Francesca; Russo, Francesca; Rosi, Paolo; Palù, Giorgio; Bisoffi, Zeno

    2014-02-05

    Since 2010 Veneto region (North-Eastern Italy) planned a special integrated surveillance of summer fevers to promptly identify cases of West Nile Fever (WNF), dengue (DENV) and chikungunya (CHIKV). The objectives of this study were (i) To increase the detection rate of imported CHIKV and DENV cases in travellers from endemic areas and promptly identify potential autochthonous cases.(ii) To detect autochthonous cases of WNF, besides those of West Nile Neuroinvasive Disease (WNND) that were already included in a national surveillance. Human surveillance: a traveler who had returned within the previous 15 days from endemic countries, with fever >38°C, absence of leucocytosis (leukocyte count 38°C for Entomologic surveillance: for West Nile (WNV) it was carried out from May through November placing CDC-CO2 traps in five provinces of Veneto Region, while for DENV and CHIKV it was also performed around residences of viremic cases. Human surveillance: between 2010 and 2012, 234 patients with fever after travelling were screened, of which 27 (11,5%) were found infected (24 with DENV and 3 with CHIKV). No autochthonous case of DENV or CHIKV was detected. Autochthonous patients screened for WNF were 408, and 24 (5,9%) were confirmed cases. Entomologic surveillance: the WNV was found in 10, 2 and 11 pools of Culex pipiens from 2010 to 2012 respectively, in sites of Rovigo, Verona, Venezia and Treviso provinces). No infected Aedes albopictus with DENV or CHIKV was found. Veneto is the only Italian region reporting WNV human cases every year since 2008. WNV is likely to cause sporadic cases and unforeseeable outbreaks for decades. Including WNF in surveillance provides additional information and possibly an early alert system. Timely detection of DENV and CHIKV should prompt vector control measures to prevent local outbreaks.

  6. Treatment model of dengue hemorrhagic fever infection in human body

    Science.gov (United States)

    Handayani, D.; Nuraini, N.; Primasari, N.; Wijaya, K. P.

    2014-03-01

    The treatment model of DHF presented in this paper involves the dynamic of five time-dependent compartments, i.e. susceptible, infected, free virus particle, immune cell, and haematocrit level. The treatment model is investigated based on normalization of haematocrit level, which is expressed as intravenous fluid infusion control. We analyze the stability of the disease free equilibrium and the endemic equilibrium. The numerical simulations will explain the dynamic of each compartment in human body. These results show particularly that infected compartment and free virus particle compartment are tend to be vanished in two weeks after the onset of dengue virus. However, these simulation results also show that without the treatment, the haematocrit level will decrease even though not up to the normal level. Therefore the effective haematocrit normalization should be done with the treatment control.

  7. Dengue viral infections

    Directory of Open Access Journals (Sweden)

    Gurugama Padmalal

    2010-01-01

    Full Text Available Dengue viral infections are one of the most important mosquito-borne diseases in the world. Presently dengue is endemic in 112 countries in the world. It has been estimated that almost 100 million cases of dengue fever and half a million cases of dengue hemorrhagic fever (DHF occur worldwide. An increasing proportion of DHF is in children less than 15 years of age, especially in South East and South Asia. The unique structure of the dengue virus and the pathophysiologic responses of the host, different serotypes, and favorable conditions for vector breeding have led to the virulence and spread of the infections. The manifestations of dengue infections are protean from being asymptomatic to undifferentiated fever, severe dengue infections, and unusual complications. Early recognition and prompt initiation of appropriate supportive treatment are often delayed resulting in unnecessarily high morbidity and mortality. Attempts are underway for the development of a vaccine for preventing the burden of this neglected disease. This review outlines the epidemiology, clinical features, pathophysiologic mechanisms, management, and control of dengue infections.

  8. Dengue fever spreading based on probabilistic cellular automata with two lattices

    Science.gov (United States)

    Pereira, F. M. M.; Schimit, P. H. T.

    2018-06-01

    Modeling and simulation of mosquito-borne diseases have gained attention due to a growing incidence in tropical countries in the past few years. Here, we study the dengue spreading in a population modeled by cellular automata, where there are two lattices to model the human-mosquitointeraction: one lattice for human individuals, and one lattice for mosquitoes in order to enable different dynamics in populations. The disease considered is the dengue fever with one, two or three different serotypes coexisting in population. Although many regions exhibit the incidence of only one serotype, here we set a complete framework to also study the occurrence of two and three serotypes at the same time in a population. Furthermore, the flexibility of the model allows its use to other mosquito-borne diseases, like chikungunya, yellow fever and malaria. An approximation of the cellular automata is proposed in terms of ordinary differential equations; the spreading of mosquitoes is studied and the influence of some model parameters are analyzed with numerical simulations. Finally, a method to combat dengue spreading is simulated based on a reduction of mosquito birth and mosquito bites in population.

  9. 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.

  10. Data mining for dengue hemorrhagic fever (DHF) prediction with naive Bayes method

    Science.gov (United States)

    Arafiyah, Ria; Hermin, Fariani

    2018-01-01

    Handling of infectious diseases is determined by the accuracy and speed of diagnosis. Government through the Regulation of the Minister of Health of the Republic of Indonesia No. 82 of 2014 on the Control of Communicable Diseases establishes Dengue Hemorrhagic Fever (DHF) has made DHF prevention a national priority. Various attempts were made to overcome this misdiagnosis. The treatment and diagnosis of DHF using ANFIS has result an application program that can decide whether a patient has dengue fever or not [1]. An expert system of dengue prevention by using ANFIS has predict the weather and the number of sufferers [2]. The large number of data on DHF often cannot affect a person in making decisions. The use of data mining method, able to build data base support in decision makers diagnose DHF disease [3]. This study predicts DHF with the method of Naive Bayes. Parameter of The input variable is the patient’s medical data (temperature, spotting, bleeding, and tornuine test) and the output variable suffers from DBD or not while the system output is diagnosis of the patient suffering from DHF or not. Result of model test by using tools of Orange 3.4.5 obtained level of precision model is 77,3%.

  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. Dengue viral infections

    OpenAIRE

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

    2004-01-01

    Dengue viral infections are one of the most important mosquito borne diseases in the world. They may be asymptomatic or may give rise to undifferentiated fever, dengue fever, dengue haemorrhagic fever (DHF), or dengue shock syndrome. Annually, 100 million cases of dengue fever and half a million cases of DHF occur worldwide. Ninety percent of DHF subjects are children less than 15 years of age. At present, dengue is endemic in 112 countries in the world. No vaccine is available for preventing...

  13. Synchrony of sylvatic dengue isolations: a multi-host, multi-vector SIR model of dengue virus transmission in Senegal.

    Directory of Open Access Journals (Sweden)

    Benjamin M Althouse

    Full Text Available Isolations of sylvatic dengue-2 virus from mosquitoes, humans and non-human primates in Senegal show synchronized multi-annual dynamics over the past 50 years. Host demography has been shown to directly affect the period between epidemics in other pathogen systems, therefore, one might expect unsynchronized multi-annual cycles occurring in hosts with dramatically different birth rates and life spans. However, in Senegal, we observe a single synchronized eight-year cycle across all vector species, suggesting synchronized dynamics in all vertebrate hosts. In the current study, we aim to explore two specific hypotheses: 1 primates with different demographics will experience outbreaks of dengue at different periodicities when observed as isolated systems, and that coupling of these subsystems through mosquito biting will act to synchronize incidence; and 2 the eight-year periodicity of isolations observed across multiple primate species is the result of long-term cycling in population immunity in the host populations. To test these hypotheses, we develop a multi-host, multi-vector Susceptible, Infected, Removed (SIR model to explore the effects of coupling multiple host-vector systems of dengue virus transmission through cross-species biting rates. We find that under small amounts of coupling, incidence in the host species synchronize. Long-period multi-annual dynamics are observed only when prevalence in troughs reaches vanishingly small levels (< 10(-10, suggesting that these dynamics are inconsistent with sustained transmission in this setting, but are consistent with local dengue virus extinctions followed by reintroductions. Inclusion of a constant introduction of infectious individuals into the system causes the multi-annual periods to shrink, while the effects of coupling remain the same. Inclusion of a stochastic rate of introduction allows for multi-annual periods at a cost of reduced synchrony. Thus, we conclude that the eight-year period

  14. Molecular Epidemiological Analysis of Dengue Fever in Bolivia from 1998 to 2008

    Science.gov (United States)

    Roca, Yelin; Baronti, Cécile; Revollo, Roberto Jimmy; Cook, Shelley; Loayza, Roxana; Ninove, Laetitia; Fernandez, Roberto Torrez; Flores, Jorge Vargas; Herve, Jean-Pierre; de Lamballerie, Xavier

    2012-01-01

    Dengue fever was first recognized in Bolivia in 1931. However, very limited information was available to date regarding the genetic characterization and epidemiology of Bolivian dengue virus strains. Here, we performed genetic characterization of the full-length envelope gene of 64 Bolivian isolates from 1998 to 2008 and investigated their origin and evolution to determine whether strains circulated simultaneously or alternatively, and whether or not multiple introductions of distinct viral variants had occurred during the period studied. We determined that, during the last decade, closely related viruses circulated during several consecutive years (5, 6, and 6 years for DENV-1, DENV-2, and DENV-3, respectively) and the co-circulation of two or even three serotypes was observed. Emergence of new variants (distinct from those identified during the previous episodes) was identified in the case of DENV-1 (2007 outbreak) and DENV-2 (2001 outbreak). In all cases, it is likely that the viruses originated from neighboring countries. PMID:19505253

  15. Germ line transformation of the yellow fever mosquito, Aedes aegypti, mediated by transpositional insertion of a piggyBac vector.

    Science.gov (United States)

    Lobo, N F; Hua-Van, A; Li, X; Nolen, B M; Fraser, M J

    2002-04-01

    Mosquito-vectored diseases such as yellow fever and dengue fever continue to have a substantial impact on human populations world-wide. Novel strategies for control of these mosquito vectored diseases can arise through the development of reliable systems for genetic manipulation of the insect vector. A piggyBac vector marked with the Drosophila melanogaster cinnabar (cn) gene was used to transform the white-eyed khw strain of Aedes aegypti. Microinjection of preblastoderm embryos resulted in four families of cinnabar transformed insects. An overall transformation frequency of 4%, with a range of 0% to as high as 13% for individual experiments, was achieved when using a heat-shock induced transposase providing helper plasmid. Southern hybridizations indicated multiple insertion events in three of four transgenic lines, while the presence of duplicated target TTAA sites at either ends of individual insertions confirmed characteristic piggyBac transposition events in these three transgenic lines. The transgenic phenotype has remained stable for more than twenty generations. The transformations effected using the piggyBac element establish the potential of this element as a germ-line transformation vector for Aedine mosquitoes.

  16. Health Seeking Behaviour and Treatment Intentions of Dengue and Fever: A Household Survey of Children and Adults in Venezuela

    Science.gov (United States)

    Elsinga, Jelte; Lizarazo, Erley F.; Vincenti, Maria F.; Schmidt, Masja; Velasco-Salas, Zoraida I.; Arias, Luzlexis; Bailey, Ajay; Tami, Adriana

    2015-01-01

    Background Dengue in Venezuela is a major public health problem with an increasing incidence of severe cases. Early diagnosis and timely treatment influences the outcome of dengue illness, as delay in care-seeking is significantly associated with complications leading to severe dengue. We aimed to understand patterns of health seeking behaviour (HSB) in individuals exposed to high dengue incidence in order to improve early attendance to health centres. Methods Between September 2013 and February 2014 a cross-sectional household survey was performed in Maracay, Venezuela. Intended HSB of adults and children’s parents/guardians was assessed with respect to fever or suspected dengue. Data was collected through structured questionnaires from 105 individuals. Results Most individuals felt at risk of dengue and believed it could be a deadly disease. In the case of suspected dengue, the majority (60%) would choose to first seek medical help versus first treating at home, in contrast to 11% in the case of fever. Amongst those who decided to visit a doctor, a suspected dengue infection would prompt them to search medical help earlier than if having only fever (ptreating at home in the case of dengue were feeling at risk (OR = 3.29; p = 0.042) and being an adult (as opposed to caring for a child as a parent/guardian; OR = 3.33, p = 0.021), while having had a previous dengue infection (OR = 0.29; p = 0.031) and living in the neighbourhood Caña de Azúcar (OR = 0.28, p = 0.038) were negatively associated with seeking medical care as their first action. Conclusion Knowledge of HSB related to dengue is scarce in the Americas, our study attempts to contribute to a better understanding of HSB in this region. Improving early dengue disease recognition and awareness may enhance prompt attendance to medical care in affected populations and thereby reduce mortality and severity of dengue. Especially for those with a previous dengue infection, efforts have to be made to promote

  17. Health Seeking Behaviour and Treatment Intentions of Dengue and Fever: A Household Survey of Children and Adults in Venezuela.

    Science.gov (United States)

    Elsinga, Jelte; Lizarazo, Erley F; Vincenti, Maria F; Schmidt, Masja; Velasco-Salas, Zoraida I; Arias, Luzlexis; Bailey, Ajay; Tami, Adriana

    2015-12-01

    Dengue in Venezuela is a major public health problem with an increasing incidence of severe cases. Early diagnosis and timely treatment influences the outcome of dengue illness, as delay in care-seeking is significantly associated with complications leading to severe dengue. We aimed to understand patterns of health seeking behaviour (HSB) in individuals exposed to high dengue incidence in order to improve early attendance to health centres. Between September 2013 and February 2014 a cross-sectional household survey was performed in Maracay, Venezuela. Intended HSB of adults and children's parents/guardians was assessed with respect to fever or suspected dengue. Data was collected through structured questionnaires from 105 individuals. Most individuals felt at risk of dengue and believed it could be a deadly disease. In the case of suspected dengue, the majority (60%) would choose to first seek medical help versus first treating at home, in contrast to 11% in the case of fever. Amongst those who decided to visit a doctor, a suspected dengue infection would prompt them to search medical help earlier than if having only fever (p<0.001). Multivariate analysis modelling showed that the independent factors associated with the intention to firstly visit a doctor versus treating at home in the case of dengue were feeling at risk (OR = 3.29; p = 0.042) and being an adult (as opposed to caring for a child as a parent/guardian; OR = 3.33, p = 0.021), while having had a previous dengue infection (OR = 0.29; p = 0.031) and living in the neighbourhood Caña de Azúcar (OR = 0.28, p = 0.038) were negatively associated with seeking medical care as their first action. Knowledge of HSB related to dengue is scarce in the Americas, our study attempts to contribute to a better understanding of HSB in this region. Improving early dengue disease recognition and awareness may enhance prompt attendance to medical care in affected populations and thereby reduce mortality and severity of

  18. aeGEPUCI: a database of gene expression in the dengue vector mosquito, Aedes aegypti

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    James Anthony A

    2010-10-01

    Full Text Available Abstract Background Aedes aegypti is the principal vector of dengue and yellow fever viruses. The availability of the sequenced and annotated genome enables genome-wide analyses of gene expression in this mosquito. The large amount of data resulting from these analyses requires efficient cataloguing before it becomes useful as the basis for new insights into gene expression patterns and studies of the underlying molecular mechanisms for generating these patterns. Findings We provide a publicly-accessible database and data-mining tool, aeGEPUCI, that integrates 1 microarray analyses of sex- and stage-specific gene expression in Ae. aegypti, 2 functional gene annotation, 3 genomic sequence data, and 4 computational sequence analysis tools. The database can be used to identify genes expressed in particular stages and patterns of interest, and to analyze putative cis-regulatory elements (CREs that may play a role in coordinating these patterns. The database is accessible from the address http://www.aegep.bio.uci.edu. Conclusions The combination of gene expression, function and sequence data coupled with integrated sequence analysis tools allows for identification of expression patterns and streamlines the development of CRE predictions and experiments to assess how patterns of expression are coordinated at the molecular level.

  19. La epidemiología del dengue y del dengue hemorrágico en Santiago de Cuba, 1997 The epidemiology of dengue and dengue hemorrhagic fever in Santiago de Cuba, 1997

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    Luis Valdés

    1999-07-01

    Full Text Available En 1977, Cuba informó de su primera epidemia de dengue, durante la cual se registraron más de 500 000 casos de fiebre del dengue causados por el serotipo 1 del virus. En 1981, se produjo una gran epidemia de dengue hemorrágico causada por el serotipo 2. Esa vez se notificaron 344 203 casos en total, 10 312 casos clínicos de dengue hemorrágico y 158 defunciones, de las cuales 101 correspondieron a niños. Por medio de una búsqueda activa con confirmación de laboratorio, en el municipio de Santiago de Cuba de la provincia del mismo nombre se detectó precozmente en enero de 1997 la reintroducción del dengue, específicamente del virus del tipo 2, genotipo Jamaica. En este trabajo se presentan los aspectos epidemiológicos de mayor interés referentes a esa epidemia. Se notificaron 3 012 casos confirmados por serología, 205 clasificados como fiebre hemorrágica del dengue/síndrome de choque del dengue, de los cuales 12 fallecieron (todos adultos. La infección secundaria por virus del dengue fue uno de los principales factores de riesgo en el desarrollo de dengue hemorrágico y 98% de los casos, así como 92% de los fallecidos, manifestaron una respuesta de tipo secundario. Por primera vez se observó la posibilidad de contraer dengue hemorrágico en personas con una infección secundaria de 16 a 20 años después de la primera infección. Pertenecer a la raza blanca fue otro factor de riesgo de importancia, tal como se había observado desde la epidemia de 1981. En la última epidemia se demostró que la llamada “alerta de fiebre” no es útil para la detección temprana de una epidemia. Las medidas tomadas por las autoridades sanitarias del país evitaron la extensión de la epidemia a otros municipios que estaban infestados por Aedes aegypti.A dengue epidemic that Cuba reported in 1997 registered more than 500 000 cases of dengue fever produced by viral serotype 1. In 1981, there was an epidemic of dengue hemorrhagic fever produced by

  20. Sociodemographic Factors to Dengue Hemmorrhagic Fever Case in Indonesia

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    Desy Nuryunarsih

    2015-08-01

    Indonesia Demam berdarah dengue (DBD adalah penyebab utama rawat inap dan kematian pada anak-anak. Indonesia adalah salah satu negara yang oleh WHO dikategorikan hyperendemicity dengan empat serotipe virus tersebar di daerah perkotaan. Faktor sosiodemografi dianggap sebagai faktor pendukung terjadinya DBD di Indonesia. Studi ini menggunakan data sekunder yang diunduh dari Basis Data Kesehatan Provinsi tahun 2010 Kementerian Kesehatan Republik Indonesia untuk menentukan korelasi antara ketiga faktor sosiodemografi dengan insiden DBD. Penelitian ini menggunakan metode kuantitatif deskripsi korelasi. Hasil penelitian menunjukkan bahwa dua faktor sosiodemografi terpilih memiliki korelasi linier dengan insiden DBD. Analisa regresi multivariat menunjukkan kecilnya korelasi antara insiden DBD dengan sekaligus tiga faktor sosiodemografi terpilih. Akan tetapi, hasil perhitungan analisa regresi univariat menunjukkan bahwa kepadatan penduduk dan kemiskinan memiliki korelasi yang signifikan terhadap DBD. Kepadatan penduduk r(4 = 0,843, nilai p < 0,05, sedangkan kemiskinan r(4= 0,897, nilai p < 0,05. Variabel usia di bawah 15 tahun tidak memiliki korelasi positif terhadap insiden DBD. Diharapkan penelitian ini dapat memiliki kontribusi terhadap program pencegahan DBD dengan cara membantu praktisi kesehatan masyarakat mengembangkan strategi pencegahan DBD, terutama yang berhubungan dengan faktor sosiodemografi.

  1. Enhancing the Immunogenicity of a Tetravalent Dengue DNA Vaccine

    Science.gov (United States)

    2016-08-01

    season’s influenza vaccine. There is no overlap with the proposed project. Title: Serological survey for Zika virus and other vector-borne pathogen...studying human immunology and pathogenesis of dengue virus infection Time Commitments: 5% 0.6 calendar months Supporting Agency: Military Infectious...attenuated dengue virus vaccine (LAV), and (3) inactivated dengue virus vaccine. Dengue fever ranks among the top infectious diseases that afflict

  2. Knowledge of nurses towards dengue fever in a tertiary care teaching hospital in Nepal

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    S Valarmathi

    2014-01-01

    Full Text Available Background: Nurses are important health care professionals and should have wide knowledge about common diseases especially infectious diseases like dengue. Dengue is associated with shock and can lead to death. Aim: To assess the knowledge of nurses regarding dengue fever and to study the association between the demographic variables. Setting and design: A cross sectional study was conducted at the College of Medical Sciences-Teaching Hospital, Nepal among the nurses during December, 2010. Study tool: Semi structured question was prepared to assess the knowledge of nurses in which there was objective question and Yes or No type questionnaire. Statistical analysis: The filled questionnaires were collected and data were entered in Microsoft excel sheet and analyzed as per study objectives. Descriptive statistic was used to calculate the median (IQR and non parametric tests (Kruskal Wallis test and Mann Whitney test to compare the total scores with demographic profile of the subjects. Results: Of the study members 89% were from Proficiency Certificate level (PCL background and the mean (IQR age of the respondents was 21 years (20-22.75. Overall score of the nurses was 11 (9-13 with a maximum possible score of 17. There were no association between the respondents knowledge scores with age (p=0.14; educational qualifications (p=0.86; duration of experience (p=0.59; ward (p=0.28. Conclusion: The study findings report a low knowledge among the nursing practitioners on dengue fever and its complications and their knowledge did not have any association with their demographic variables. Journal of College of Medical Sciences-Nepal, 2013, Vol-9, No-1, 7-13 DOI: http://dx.doi.org/10.3126/jcmsn.v9i1.9667

  3. Estimating the size of Aedes aegypti populations from dengue incidence data: Implications for the risk of yellow fever outbreaks

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    Eduardo Massad

    2017-11-01

    Full Text Available In this paper we present a model to estimate the density of aedes mosquitoes in a community affected by dengue. The method consists in fitting a continuous function to the incidence of dengue infections, from which the density of infected mosquitoes is derived straightforwardly. Further derivations allow the calculation of the latent and susceptible mosquitoes' densities, the sum of the three equals the total mosquitoes' density. The method is illustrated with the case of the risk of urban yellow fever resurgence in dengue infested areas but the same procedures apply for other aedes-transmitted infections like Zika and chikungunya viruses.

  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

    2013-01-01

    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. PMID:23874141

  5. Individual and Interactive Effects of Socio-Ecological Factors on Dengue Fever at Fine Spatial Scale: A Geographical Detector-Based Analysis.

    Science.gov (United States)

    Cao, Zheng; Liu, Tao; Li, Xing; Wang, Jin; Lin, Hualiang; Chen, Lingling; Wu, Zhifeng; Ma, Wenjun

    2017-07-17

    Background : Large spatial heterogeneity was observed in the dengue fever outbreak in Guangzhou in 2014, however, the underlying reasons remain unknown. We examined whether socio-ecological factors affected the spatial distribution and their interactive effects. Methods : Moran's I was applied to first examine the spatial cluster of dengue fever in Guangzhou. Nine socio-ecological factors were chosen to represent the urbanization level, economy, accessibility, environment, and the weather of the 167 townships/streets in Guangzhou, and then the geographical detector was applied to analyze the individual and interactive effects of these factors on the dengue outbreak. Results : Four clusters of dengue fever were identified in Guangzhou in 2014, including one hot spot in the central area of Guangzhou and three cold spots in the suburban districts. For individual effects, the temperature ( q = 0.33) was the dominant factor of dengue fever, followed by precipitation ( q = 0.24), road density ( q = 0.24), and water body area ( q = 0.23). For the interactive effects, the combination of high precipitation, high temperature, and high road density might result in increased dengue fever incidence. Moreover, urban villages might be the dengue fever hot spots. Conclusions : Our study suggests that some socio-ecological factors might either separately or jointly influence the spatial distribution of dengue fever in Guangzhou.

  6. 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.

  7. "We need people to collaborate together against this disease": A qualitative exploration of perceptions of dengue fever control in caregivers' of children under 5 years, in the Peruvian Amazon.

    Science.gov (United States)

    Frank, Amy L; Beales, Emily R; de Wildt, Gilles; Meza Sanchez, Graciela; Jones, Laura L

    2017-09-01

    Dengue Fever presents a significant and growing burden of disease to endemic countries, where children are at particular risk. Worldwide, no effective anti-viral treatment has been identified, thus vector control is key for disease prevention, particularly in Peru where no vaccine is currently available. This qualitative study aimed to explore the perceptions of dengue control in caregivers' of children under 5 years in Peru, to help direct future mosquito control programmes and strategy. Eighteen semi-structured interviews were conducted in one health centre in Iquitos, Peru. Interviews were audio-recorded, transcribed and translated by an independent translator. Data were analysed using an inductive thematic approach. Three core analytic themes were interpreted: (1) awareness of dengue and its control, (2) perceived susceptibility of children, rural riverside communities and city inhabitants, and (3) perceived responsibility of vector control. Participants were aware of dengue symptoms, transmission and larvae eradication strategies. Misconceptions about the day-time biting behaviour of the Aedes aegypti mosquito and confusion with other mosquito-borne diseases influenced preventative practice. Community-wide lack of cooperation was recognised as a key barrier. This was strengthened by attitudes that the government or health centre were responsible for dengue control and a belief that the disease cannot be prevented through individual actions. Participants felt powerless to prevent dengue due to assumed inevitability of infection and lack of faith in preventative practices. However, children and rural communities were believed to be most vulnerable. Perceptions of dengue control amongst caregivers to under 5's were important in shaping their likelihood to participate in preventative practices. There is a need to address the perceived lack of community cooperation through strategies creating a sense of ownership of community control and enhancing social

  8. [Yellow fever virus, dengue 2 and other arboviruses isolated from mosquitos, in Burkina Faso, from 1983 to 1986. Entomological and epidemiological considerations].

    Science.gov (United States)

    Robert, V; Lhuillier, M; Meunier, D; Sarthou, J L; Monteny, N; Digoutte, J P; Cornet, M; Germain, M; Cordellier, R

    1993-01-01

    An arbovirus surveillance was carried out in Burkina Faso from 1983 to 1986. It was based on crepuscular catches of mosquitoes on human bait in some wooded areas and in one town. The total collection was 228 catches with an average of 8 men per catch. The total number of mosquitoes caught was 44,956 among which 32,010 potential vector of yellow fever; all these mosquitoes were analysed for arbovirology. In the south-western part of the country (region of Bobo-Dioulasso), surveillance was conducted each year from August to November, whilst the circulation of Aedes-borne arboviruses is well known to be favoured. In 1983, 1984 and 1986, seven strains of yellow fever virus were isolated in circumstances remarkably similar. They came from selvatic areas and never from the town. They concerned only Aedes (Stegomyia) luteocephalus which is the very predominant potential vector of yellow fever in the region. They were obtained in low figure, between 1 and 4 per year. They occurred from 27th of October to 21th of November. These observations confirm that the southern portion of the Sudan savanna zone of West Africa is the setting of a customary circulation of yellow fever virus and therefore belongs to the endemic emergence zone. In 1986, two strains of dengue 2 virus were isolated. One concerned Ae. luteocephalus from the selvatic area, the other Ae. (St.) aegypti from the heart of town. These data suggest two distinct cycles for dengue 2 virus, one urban and one selvatic, which could coexist simultaneously in the same region. In the south-eastern part of the country (region of Fada-N'Gourma) a yellow fever epidemic occurred between September and December 1983; its study has enable to precise their entomological aspects. The entomological inoculation rate of yellow fever virus has been evaluated to 22 infected bites per man during the month of october, for a man living close to forest gallery. 25 strains of yellow fever virus strains was isolated from Ae. (Diceromyia

  9. Lethal response of the dengue vectors to the plant extracts from family Anacardiaceae

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    Ali Yousaf

    2015-10-01

    Conclusions: Ae. albopictus has been found to be more susceptible as compare to Aedes aegypti in both laboratory and field strains in this study. G. renghas and M. fasciculiflora were tested for the first time and exhibited prompting larvicidal activities against dengue vectors. These results revealed that all the plants especially G. renghas and M. fasciculiflora have the higher larvicidal activities and can be used for the control of dengue vector as a new environment friendly, target specific and low cost phytochemical.

  10. Dengue incidence in urban and rural Cambodia: results from population-based active fever surveillance, 2006-2008.

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    Sirenda Vong

    Full Text Available BACKGROUND: Dengue vaccines are now in late-stage development, and evaluation and robust estimates of dengue disease burden are needed to facilitate further development and introduction. In Cambodia, the national dengue case-definition only allows reporting of children less than 16 years of age, and little is known about dengue burden in rural areas and among older persons. To estimate the true burden of dengue in the largest province of Cambodia, Kampong Cham, we conducted community-based active dengue fever surveillance among the 0-to-19-year age group in rural villages and urban areas during 2006-2008. METHODS AND FINDINGS: Active surveillance for febrile illness was conducted in 32 villages and 10 urban areas by mothers trained to use digital thermometers combined with weekly home visits to identify persons with fever. An investigation team visited families with febrile persons to obtain informed consent for participation in the follow-up study, which included collection of personal data and blood specimens. Dengue-related febrile illness was defined using molecular and serological testing of paired acute and convalescent blood samples. Over the three years of surveillance, 6,121 fever episodes were identified with 736 laboratory-confirmed dengue virus (DENV infections for incidences of 13.4-57.8/1,000 person-seasons. Average incidence was highest among children less than 7 years of age (41.1/1,000 person-seasons and lowest among the 16-to-19-year age group (11.3/1,000 person-seasons. The distribution of dengue was highly focal, with incidence rates in villages and urban areas ranging from 1.5-211.5/1,000 person-seasons (median 36.5. During a DENV-3 outbreak in 2007, rural areas were affected more than urban areas (incidence 71 vs. 17/1,000 person-seasons, p<0.001. CONCLUSION: The large-scale active surveillance study for dengue fever in Cambodia found a higher disease incidence than reported to the national surveillance system, particularly

  11. Incidence of dengue virus infections in febrile episodes in Ile-Ife ...

    African Journals Online (AJOL)

    While dengue infection is accompanied by little or no subclinical signs in many, about 1-2% may produce clinically severe Dengue Haemorrhagic Fever/Dengue Shock Syndrome. Early recognition, appropriate treatment and elimination of mosquito vectors will help control it. The study is aimed at determining the incidence ...

  12. INTERIM ANALYSIS OF THE CONTRIBUTION OF HIGH-LEVEL EVIDENCE FOR DENGUE VECTOR CONTROL.

    Science.gov (United States)

    Horstick, Olaf; Ranzinger, Silvia Runge

    2015-01-01

    This interim analysis reviews the available systematic literature for dengue vector control on three levels: 1) single and combined vector control methods, with existing work on peridomestic space spraying and on Bacillus thuringiensis israelensis; further work is available soon on the use of Temephos, Copepods and larvivorous fish; 2) or for a specific purpose, like outbreak control, and 3) on a strategic level, as for example decentralization vs centralization, with a systematic review on vector control organization. Clear best practice guidelines for methodology of entomological studies are needed. There is a need to include measuring dengue transmission data. The following recommendations emerge: Although vector control can be effective, implementation remains an issue; Single interventions are probably not useful; Combinations of interventions have mixed results; Careful implementation of vector control measures may be most important; Outbreak interventions are often applied with questionable effectiveness.

  13. Evaluation of the Larvicidal Efficacy of Five Indigenous Weeds against an Indian Strain of Dengue Vector, Aedes aegypti L. (Diptera: Culicidae)

    Science.gov (United States)

    Sharma, Aarti; Kumar, Sarita; Tripathi, Pushplata

    2016-01-01

    Background and Objectives. Aedes aegypti, dengue fever mosquito, is primarily associated with the transmission of dengue and chikungunya in tropical and subtropical regions of the world. The present investigations were carried out to assess the larvicidal efficiency of five indigenous weeds against Ae. aegypti. Methods. The 1,000 ppm hexane and ethanol extracts prepared from the leaves and stem of five plants (Achyranthes aspera, Cassia occidentalis, Catharanthus roseus, Lantana camara, and Xanthium strumarium) were screened for their larvicidal activity against early fourth instars of dengue vector. The extracts which could cause 80–100% mortality were further investigated for their efficacy. Results. The preliminary screening established the efficacy of hexane extracts as compared to the ethanol extracts. Further investigations revealed the highest larvicidal potential of A. aspera extracts exhibiting LC50 value of 82.555 ppm and 68.133 ppm, respectively. Further, their leaf extracts showed 5–85.9% higher larvicidal activity and stem extracts exhibited 0.23- to 0.85-fold more efficiency than the other four extracts. Conclusion. The present investigations suggest the possible use of A. aspera as an ideal ecofriendly, larvicidal agent for the control of dengue vector, Ae. aegypti. Future studies are, however, required to explore and identify the bioactive component involved and its mode of action. PMID:26941996

  14. Evaluation of the Larvicidal Efficacy of Five Indigenous Weeds against an Indian Strain of Dengue Vector, Aedes aegypti L. (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    Aarti Sharma

    2016-01-01

    Full Text Available Background and Objectives. Aedes aegypti, dengue fever mosquito, is primarily associated with the transmission of dengue and chikungunya in tropical and subtropical regions of the world. The present investigations were carried out to assess the larvicidal efficiency of five indigenous weeds against Ae. aegypti. Methods. The 1,000 ppm hexane and ethanol extracts prepared from the leaves and stem of five plants (Achyranthes aspera, Cassia occidentalis, Catharanthus roseus, Lantana camara, and Xanthium strumarium were screened for their larvicidal activity against early fourth instars of dengue vector. The extracts which could cause 80–100% mortality were further investigated for their efficacy. Results. The preliminary screening established the efficacy of hexane extracts as compared to the ethanol extracts. Further investigations revealed the highest larvicidal potential of A. aspera extracts exhibiting LC50 value of 82.555 ppm and 68.133 ppm, respectively. Further, their leaf extracts showed 5–85.9% higher larvicidal activity and stem extracts exhibited 0.23- to 0.85-fold more efficiency than the other four extracts. Conclusion. The present investigations suggest the possible use of A. aspera as an ideal ecofriendly, larvicidal agent for the control of dengue vector, Ae. aegypti. Future studies are, however, required to explore and identify the bioactive component involved and its mode of action.

  15. Attenuation and immunogenicity of recombinant yellow fever 17D-dengue type 2 virus for rhesus monkeys

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    Galler R.

    2005-01-01

    Full Text Available A chimeric yellow fever (YF-dengue serotype 2 (dengue 2 virus was constructed by replacing the premembrane and envelope genes of the YF 17D virus with those from dengue 2 virus strains of Southeast Asian genotype. The virus grew to high titers in Vero cells and, after passage 2, was used for immunogenicity and attenuation studies in rhesus monkeys. Subcutaneous immunization of naive rhesus monkeys with the 17D-D2 chimeric virus induced a neutralizing antibody response associated with the protection of 6 of 7 monkeys against viremia by wild-type dengue 2 virus. Neutralizing antibody titers to dengue 2 were significantly lower in YF-immune animals than in YF-naive monkeys and protection against challenge with wild-type dengue 2 virus was observed in only 2 of 11 YF-immune monkeys. An anamnestic response to dengue 2, indicated by a sharp increase of neutralizing antibody titers, was observed in the majority of the monkeys after challenge with wild-type virus. Virus attenuation was demonstrated using the standard monkey neurovirulence test. The 17D-D2 chimera caused significantly fewer histological lesions than the YF 17DD virus. The attenuated phenotype could also be inferred from the limited viremias compared to the YF 17DD vaccine. Overall, these results provide further support for the use of chimeric viruses for the development of a new live tetravalent dengue vaccine.

  16. Factors Associated with the Time of Admission among Notified Dengue Fever Cases in Region VIII Philippines from 2008 to 2014.

    Science.gov (United States)

    Abello, Jason Echavez; Gil Cuesta, Julita; Cerro, Boyd Roderick; Guha-Sapir, Debarati

    2016-10-01

    In cases of Dengue fever, late hospital admission can lead to treatment delay and even death. In order to improve early disease notification and management, it is essential to investigate the factors affecting the time of admission of Dengue cases. This study determined the factors associated with the time of admission among notified Dengue cases. The study covered the period between 2008 and 2014 in Region VIII, Philippines. The factors assessed were age, sex, hospital sector, hospital level, disease severity based on the 1997 WHO Dengue classification, and period of admission (distinguishing between the 2010 Dengue epidemic and non-epidemic time). We analysed secondary data from the surveillance of notified Dengue cases. We calculated the association through chi-square test, ordinal logistic regression and linear regression at p value Dengue cases. The reported cases included a majority of children (70.09%), mild cases of the disease (64.00%), patients from the public sector (69.82%), and non-tertiary hospitals (62.76%). Only 1.40% of cases had a laboratory confirmation. The epidemic period in 2010 comprised 48.68% of all the admitted cases during this period. Late admission was more likely among adults than children (pDengue guidelines in order to standardize the admission criteria and time across hospitals.

  17. CD8+ T lymphocyte expansion, proliferation and activation in dengue fever.

    Directory of Open Access Journals (Sweden)

    Andréia Manso de Matos

    2015-02-01

    Full Text Available Dengue fever induces a robust immune response, including massive T cell activation. The level of T cell activation may, however, be associated with more severe disease. In this study, we explored the level of CD8+ T lymphocyte activation in the first six days after onset of symptoms during a DENV2 outbreak in early 2010 on the coast of São Paulo State, Brazil. Using flow cytometry we detected a progressive increase in the percentage of CD8+ T cells in 74 dengue fever cases. Peripheral blood mononuclear cells from 30 cases were thawed and evaluated using expanded phenotyping. The expansion of the CD8+ T cells was coupled with increased Ki67 expression. Cell activation was observed later in the course of disease, as determined by the expression of the activation markers CD38 and HLA-DR. This increased CD8+ T lymphocyte activation was observed in all memory subsets, but was more pronounced in the effector memory subset, as defined by higher CD38 expression. Our results show that most CD8+ T cell subsets are expanded during DENV2 infection and that the effector memory subset is the predominantly affected sub population.

  18. Randomized clinical trial of human interleukin-11 in dengue fever-associated thrombocytopenia

    International Nuclear Information System (INIS)

    Suliman, M.I.; Qayum, I.

    2014-01-01

    Objective: To assess the effectiveness of recombinant human (rh) IL-11 to increase platelets count in patients suffering from Dengue fever (DF). Study Design: Randomized double blind placebo control study. Place and Duration of Study: Farooq Hospital, Lahore, from July to October 2011. Methodology: Forty hospitalized patients suffering from Dengue fever having platelets count A 30000 per micro liter were randomly categorized into two groups, rhIL-11 (test) and distilled water (placebo) groups. The efficacy outcomes (as indicated by step up in platelets count at 48 hours) for the treatment group were compared with the outcomes for the placebo group. Results: The data revealed that the increase in platelet response with recombinant human interleukin 11, 1.5 mg subcutaneously is significantly more brisk than the placebo group. The platelets response in patients with severe thrombocytopenia was greater in the treatment group (50%) at 48 hours as compared to the placebo group (20%) (p=0.047). Response rate was slightly greater among males (6/10, 60%) than females (8/16, 50%); moreover, three-fourth (75%) female responders were in the placebo group, compared to half (50%) male responders in the treatment group. Conclusion: Results of the study suggest that treatment of severe thrombocytopenia accompanying DF with recombinant human interleukin 11 may be a useful therapeutic option. (author)

  19. [Dengue fever in Portuguese speaking countries: which epidemiological links may we set?].

    Science.gov (United States)

    Silvano, José; Abreu, Cândida

    2014-01-01

    The recent occurrence of a number of outbreaks of dengue in Portuguese speaking countries with no previous disease, aroused curiosity about the competing factors for the phenomenon and a need for better knowledge of the pathology. We review the dengue-related situation in Portuguese speaking countries, linking the various outbreaks and trying to contribute to a better understanding of the phenomenon. Review of the literature on the topic and relevant information obtained from oral communications were included. The outbreaks occurred between the years of 2009 and 2013 in Cabo Verde, Madeira and Angola (excluding the endemic phenomenon in Brazil), share the same vector Aedes aegypti, but are due to different viral serotypes, as shown by genotypic studies. The strong sub-notification of the disease in Africa and lack of diagnostic tools prevent a true characterization of the situation. The hypothesis of a link between some of the outbreaks is not completely rejected. The Portuguese territory could be exposed to an increasingly high risk of dengue introduction, not only because of the proximity with these territories, but also because of the current climate changes. The main fight is, in spite of the still elusive emergent tools, the vector control. A link between the outbreaks has not been proven but local preparation of healthcare professionals, creation of public health strategies and maintenance of surveillance systems are needed. More epidemiological and entomological studies are needed to characterize the real incidence of disease in Portuguese speaking countries.

  20. Awareness regarding dengue fever among the link workers of urban health centres of Bengaluru CitySouth India

    Directory of Open Access Journals (Sweden)

    Gowda Giriyanna

    2015-06-01

    Full Text Available Objective: To assess awareness of link workers regarding dengue fever and its prevention and the effect of health education about dengue and its prevention. Methods: Prospective interventional study was conducted in selected urban health centers of Bengaluru. About 106 link workers selected by systematic random sampling were interviewed by trained investigators. Health education was given to all of them and awareness was reassessed after a gap of one month. Results: Mean age of link workers was (36.95 ± 5.88 years. A total of 49.06% of link workers were aware that dengue is caused by virus, 74.53% were aware of complications of dengue, 87.74 % were aware that dengue is spread by Aedes mosquito. After health education the above observations increased to 81.4%, 87.63%, and 90.72% respectively. Difference between mean preand post-test score was statistically significant (P < 0.05. Conclusions: Awareness regarding dengue fever and its prevention was poor among link workers, which improved significantly after health education.

  1. Online platform for applying space–time scan statistics for prospectively detecting emerging hot spots of dengue fever

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    Chien-Chou Chen

    2016-11-01

    Full Text Available Abstract Background Cases of dengue fever have increased in areas of Southeast Asia in recent years. Taiwan hit a record-high 42,856 cases in 2015, with the majority in southern Tainan and Kaohsiung Cities. Leveraging spatial statistics and geo-visualization techniques, we aim to design an online analytical tool for local public health workers to prospectively identify ongoing hot spots of dengue fever weekly at the village level. Methods A total of 57,516 confirmed cases of dengue fever in 2014 and 2015 were obtained from the Taiwan Centers for Disease Control (TCDC. Incorporating demographic information as covariates with cumulative cases (365 days in a discrete Poisson model, we iteratively applied space–time scan statistics by SaTScan software to detect the currently active cluster of dengue fever (reported as relative risk in each village of Tainan and Kaohsiung every week. A village with a relative risk >1 and p value <0.05 was identified as a dengue-epidemic area. Assuming an ongoing transmission might continuously spread for two consecutive weeks, we estimated the sensitivity and specificity for detecting outbreaks by comparing the scan-based classification (dengue-epidemic vs. dengue-free village with the true cumulative case numbers from the TCDC’s surveillance statistics. Results Among the 1648 villages in Tainan and Kaohsiung, the overall sensitivity for detecting outbreaks increases as case numbers grow in a total of 92 weekly simulations. The specificity for detecting outbreaks behaves inversely, compared to the sensitivity. On average, the mean sensitivity and specificity of 2-week hot spot detection were 0.615 and 0.891 respectively (p value <0.001 for the covariate adjustment model, as the maximum spatial and temporal windows were specified as 50% of the total population at risk and 28 days. Dengue-epidemic villages were visualized and explored in an interactive map. Conclusions We designed an online analytical tool for

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

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    Adisak Bhumiratana

    2014-01-01

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

  3. Control of dengue vector by the sterile insect technique considering logistic recruitment

    International Nuclear Information System (INIS)

    Esteva, L.; Yang, H.M.

    2006-01-01

    We propose a mathematical model to assess the effects of irradiated male insects introduction in a previously infested region, taking into account the logistic recruitment of sterile male insects. The release of sterile male insects aims to displace gradually the natural (or wild) insect from the habitat. We discuss the suitability of this release technique when applied to peridomestic adapted Aedes aegypyti mosquitoes which are transmitters of Yellow Fever and Dengue disease. (author)

  4. Control of dengue vector by the sterile insect technique considering logistic recruitment

    Energy Technology Data Exchange (ETDEWEB)

    Esteva, L. [Universidad Nacional Autonoma de Mexico, Mexico, D.F. (Mexico). Facultad de Ciencias. Dept. de Matematicas; Lab-Epifisma, Mexico, D.F. (Mexico); Yang, H.M. [Universidade Estadual de Campinas, SP (Brazil). Inst. de Matematica, Estatistica e Ciencia da Computacao. Dept. de Matematica Aplicada; Lab-Epifisma, Campinas, SP (Brazil)

    2006-07-01

    We propose a mathematical model to assess the effects of irradiated male insects introduction in a previously infested region, taking into account the logistic recruitment of sterile male insects. The release of sterile male insects aims to displace gradually the natural (or wild) insect from the habitat. We discuss the suitability of this release technique when applied to peridomestic adapted Aedes aegypyti mosquitoes which are transmitters of Yellow Fever and Dengue disease. (author)

  5. Ovicidal activity of Ageratina adenophora (Family: Asteraceae) against dengue vector, Aedes aegypti (Diptera: Culicidae)

    Science.gov (United States)

    To determine the ovicidal efficacy of different solvent leaf extracts of Ageratina adenophora against dengue vector Aedes aegypti . Methods: The ovicidal efficacy of the crude leaf extracts of A. adenophora with five different solvents (hexane, benzene, chloroform, ethyl acetate, methanol) and was ...

  6. Clinico-laboratory spectrum of dengue viral infection and risk factors associated with dengue hemorrhagic fever: a retrospective study

    OpenAIRE

    Mallhi, Tauqeer Hussain; Khan, Amer Hayat; Adnan, Azreen Syazril; Sarriff, Azmi; Khan, Yusra Habib; Jummaat, Fauziah

    2015-01-01

    Background The incidence of dengue is rising steadily in Malaysia since the first major outbreak in 1973. Despite aggressive measures taken by the relevant authorities, Malaysia is still facing worsening dengue crisis over the past few years. There is an urgent need to evaluate dengue cases for better understanding of clinic-laboratory spectrum in order to combat this disease. Methods A retrospective analysis of dengue patients admitted to a tertiary care teaching hospital during the period o...

  7. Safety issues from a Phase 3 clinical trial of a live-attenuated chimeric yellow fever tetravalent dengue vaccine.

    Science.gov (United States)

    Halstead, Scott B

    2018-02-26

    A tetravalent live-attenuated 3-dose vaccine composed of chimeras of yellow fever 17D and the four dengue viruses (CYD, also called Dengvaxia) completed phase 3 clinical testing in over 35,000 children leading to a recommendation that vaccine be administered to >/ = 9 year-olds residing in highly dengue- endemic countries. When clinical trial results were assessed 2 years after the first dose, vaccine efficacy among seropositives was high, but among seronegatives efficacy was marginal. Breakthrough dengue hospitalizations of vaccinated children occurred continuously over a period of 4-5 years post 3rd dose in an age distribution suggesting these children had been vaccinated when seronegative. This surmise was validated recently when the manufacturer reported that dengue NS1 IgG antibodies were absent in sera from hospitalized vaccinated children, an observation consistent with their having received Dengvaxia when seronegative. Based upon published efficacy data and in compliance with initial published recommendations by the manufacturer and WHO the Philippine government undertook to vaccinate 800,000-plus 9 year-olds starting in April 2016. Eighteen months later, dengue hospitalizations and a deaths were reported among vaccinated children. The benefits of administering Dengvaxia predicted by the manufacturer, WHO and others derive from scoring dengue hospitalizations of vaccinated children as vaccine failures rather than as vaccine enhanced dengue disease. Recommended regimens for administration of Dengvaxia should have been structured to warn of and avoid serious adverse events.

  8. Cerebral vasculitis and lateral rectus palsy - two rare central nervous system complications of dengue fever: two case reports and review of the literature.

    Science.gov (United States)

    Herath, H M M; Hewavithana, J S; De Silva, C M; Kularathna, O A R; Weerasinghe, N P

    2018-04-19

    Dengue fever is a common mosquito-borne viral illness with a clinical spectrum ranging from a simple febrile illness to potentially life-threatening complications such as dengue hemorrhagic fever and dengue shock syndrome. Dengue infection can affect many organs, including the central nervous system. The neurological manifestations reported in dengue infections are meningitis, encephalitis, stroke, acute disseminated encephalomyelitis, and Guillain-Barré syndrome. We report the cases of two interesting patients with confirmed dengue infection who presented with complications of possible central nervous system vasculitis and cranial nerve palsy. The first patient was a 53-year-old previously healthy Singhalese woman who developed acute-onset slurring of speech and ataxia with altered sensorium 1 day after recovery from a critical period of dengue hemorrhagic fever. Subsequent investigations revealed evidence of encephalopathy with brainstem ischemic infarctions. Her clinical picture was compatible with central nervous system vasculitis. She was treated successfully with intravenous steroids and had a full functional recovery. The second patient was a middle-aged Singhalese woman who had otherwise uncomplicated dengue infection. She developed binocular diplopia on day 4 of fever. An ocular examination revealed a convergent squint in the left eye with lateral rectus palsy but no other neurological manifestation. Central nervous system vasculitis due to dengue infection is a very rare phenomenon, and to the best of our knowledge, only one case of central nervous system vasculitis has been reported to date, in a patient of pediatric age. Cranial nerve palsy related to dengue infection is also rare, and only a few cases of isolated abducens nerve palsy have been reported to date. The two cases described in this report illustrate the rare but important central nervous system manifestations of dengue fever and support the fact that the central nervous system is one of the

  9. Assessing the risk for dengue fever based on socioeconomic and environmental variables in a geographical information system environment.

    Science.gov (United States)

    Khormi, Hassan M; Kumar, Lalit

    2012-05-01

    An important option in preventing the spread of dengue fever (DF) is to control and monitor its vector (Aedes aegypti) as well as to locate and destroy suitable mosquito breeding environments. The aim of the present study was to use a combination of environmental and socioeconomic variables to model areas at risk of DF. These variables include clinically confirmed DF cases, mosquito counts, population density in inhabited areas, total populations per district, water access, neighbourhood quality and the spatio-temporal risk of DF based on the average, weekly frequency of DF incidence. Out of 111 districts investigated, 17 (15%), covering a total area of 121 km2, were identified as of high risk, 25 (22%), covering 133 km2, were identified as of medium risk, 18 (16%), covering 180 km2, were identified as of low risk and 51 (46%), covering 726 km2, were identified as of very low risk. The resultant model shows that most areas at risk of DF were concentrated in the central part of Jeddah county, Saudi Arabia. The methods used can be implemented as routine procedures for control and prevention. A concerted intervention in the medium- and high-risk level districts identified in this study could be highly effective in reducing transmission of DF in the area as a whole.

  10. Mosquito larvicidal activities of Solanum villosum berry extract against the dengue vector Stegomyia aegypti

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    Chandra Goutam

    2008-04-01

    Full Text Available Abstract Background Vector control is facing a threat due to the emergence of resistance to synthetic insecticides. Insecticides of botanical origin may serve as suitable alternative biocontrol techniques in the future. Although several plants have been reported for mosquitocidal activity, only a few botanicals have moved from the laboratory to field use, because they are poorly characterized, in most cases active principals are not determined and most of the works are restricted to preliminary screening. Solanum villosum is a common weed distributed in many parts of India with medicinal properties, but the larvicidal activity of this plant has not been reported so far. Methods Aqueous and polar/non-polar solvent extract of fresh, mature, green berries of S. villosum was tested against Stegomyia aegypti, a common vector of dengue fever. A phytochemical analysis of chloroform:methanol extract was performed to search for the active toxic ingredient. The lethal concentration was determined (log probit analysis and compared with Malathion. The chemical nature of the active substance was also evaluated following ultraviolet-visual (UV-Vis and infrared (IR analysis. Results In a 72 hour bioassay experiment with the aqueous extract, the highest mortality was recorded in 0.5% extract. When the mortality of different solvent extracts was compared, the maximum (p p Y was positively correlated with the period of exposure (X and the log probit analysis (95% confidence level recorded lowest value (5.97 ppm at 72 hours of exposure. Phytochemical analysis of the chlororm:methanol extract reported the presence of many bioactive phytochemicals. Two toxic compounds were detected having Rf = 0.82 (70% and 73.33% mortality in 24 and 48 hours, respectively and Rf = 0.95 (40% and 50% mortality in 24 and 48 hours, respectively. IR analysis provided preliminary information about the steroidal nature of the active ingredient. Conclusion S. villosum offers promise as

  11. Fatal dengue hemorrhagic fever in adults: emphasizing the evolutionary pre-fatal clinical and laboratory manifestations.

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    Ing-Kit Lee

    Full Text Available BACKGROUND: A better description of the clinical and laboratory manifestations of fatal patients with dengue hemorrhagic fever (DHF is important in alerting clinicians of severe dengue and improving management. METHODS AND FINDINGS: Of 309 adults with DHF, 10 fatal patients and 299 survivors (controls were retrospectively analyzed. Regarding causes of fatality, massive gastrointestinal (GI bleeding was found in 4 patients, dengue shock syndrome (DSS alone in 2; DSS/subarachnoid hemorrhage, Klebsiella pneumoniae meningitis/bacteremia, ventilator associated pneumonia, and massive GI bleeding/Enterococcus faecalis bacteremia each in one. Fatal patients were found to have significantly higher frequencies of early altered consciousness (≤24 h after hospitalization, hypothermia, GI bleeding/massive GI bleeding, DSS, concurrent bacteremia with/without shock, pulmonary edema, renal/hepatic failure, and subarachnoid hemorrhage. Among those experienced early altered consciousness, massive GI bleeding alone/with uremia/with E. faecalis bacteremia, and K. pneumoniae meningitis/bacteremia were each found in one patient. Significantly higher proportion of bandemia from initial (arrival laboratory data in fatal patients as compared to controls, and higher proportion of pre-fatal leukocytosis and lower pre-fatal platelet count as compared to initial laboratory data of fatal patients were found. Massive GI bleeding (33.3% and bacteremia (25% were the major causes of pre-fatal leukocytosis in the deceased patients; 33.3% of the patients with pre-fatal profound thrombocytopenia (<20,000/µL, and 50% of the patients with pre-fatal prothrombin time (PT prolongation experienced massive GI bleeding. CONCLUSIONS: Our report highlights causes of fatality other than DSS in patients with severe dengue, and suggested hypothermia, leukocytosis and bandemia may be warning signs of severe dengue. Clinicians should be alert to the potential development of massive GI bleeding

  12. Análisis costo-beneficio del control de vectores en la transmisión potencial de dengue Cost-benefit analysis of vector control in areas of potential dengue transmission

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    Pablo Wenceslao Orellano

    2008-08-01

    , from January to April 2007, in the city of Clorinda, Argentina. Direct costs, as well as indirect and intangible benefits, were taken into account and standardized in international dollars (I$ using purchasing power parity. An incidence rate of 50 cases of dengue per 1 000 inhabitants was used in the non-intervention hypothesis. RESULTS: From January to April 2007 there were 176 cases of dengue in Clorinda, but only five were autochthonous. The net present value was I$ 196 879 with the control strategy, whereas the non-intervention was calculated to be I$ -106 724, indicating a savings of I$ 303 602 (I$ 6.46 per inhabitant for the intervention. The sensitivity analysis showed that, with more than 1 363 cases of dengue (total incidence rate of 29 per 1 000 inhabitants and one case of dengue hemorrhagic fever, there is a cost-benefit to intervention. CONCLUSIONS: The results suggest that vector control, including fumigation of adult mosquitoes, should be considered in high-risk areas as a cost-effective option for non-endemic countries.

  13. Combination immunotherapy in the treatment of chronic bilateral panuveitis and uveitic glaucoma during acute dengue fever infection in the Caribbean.

    Science.gov (United States)

    Stewart, Kevin P; Tawakol, Jan B; Khan, Tasnim; Capriotti, Joseph A

    2015-01-01

    Ocular manifestations of the dengue fever virus include bilateral panuveitis that can occur after the acute systemic infection has resolved. In most reported cases, the inflammation resolves with topical or systemic steroid therapy. We report a case of chronic, refractory bilateral panuveitis and uveitic glaucoma that began during the acute phase of the systemic infection and required treatment with oral steroids, multiple steroid-sparing agents, and surgical therapy for glaucoma. A 22-year-old male with acute systemic dengue fever presented with bilateral pain and decreased vision. Clinical examination revealed bilateral panuveitis with elevated intraocular pressures. Management required oral steroids, mycophenolate mofetil, cyclosporine, and bilateral glaucoma valve implantation. This case highlights the fact that dengue-associated panuveitis can begin in the acute stage of systemic infection and persist long after convalescence with progression to chronic bilateral panuveitis and uveitic glaucoma. Dengue-associated chronic panuveitis with uveitic glaucoma may be effectively managed with a combination of steroid-sparing oral immunosuppression and glaucoma surgery. This is, to our knowledge, the first case of bilateral refractory dengue-associated panuveitis from the Caribbean treated with combination steroid-sparing oral immunosuppression and bilateral glaucoma valve implantation.

  14. Vectors of Crimean Congo Hemorrhagic Fever Virus in Iran

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    Zakkyeh Telmadarraiy

    2015-10-01

    Full Text Available Background: Ticks are important vectors and reservoirs of Crimean Congo Hemorrhagic Fever (CCHF virus. Human beings may be infected whenever the normal life cycle of the infected ticks on non- human vertebrate hosts is interrupted by the undesirable presence of humans in the cycle. A total of 26 species of Argasid and Ixodid ticks have been recorded in Iran; including nine Hyalomma, two Rhipicephalus, two Dermacentor, five Haemaphysalis, two Boophilus, one Ixodes and two Argas as well as three Ornithodoros species as blood sucking ectoparasites of livestock and poultries. The present paper reviews tick vectors of CCHF virus in Iran, focusing on the role of ticks in different provinces of Iran using reverse transcription polymerase chain reaction (RT-PCR assay.Methods: During ten years study, 1054 tick specimens; including two species of Argasidae and 17 species of Ixodidae were examined for their infection to CCHF virus genome. The output of all studies as well as related publications were discussed in the current paper.Results: The results show that Rhipicephalus sanguineus, Hyalomma marginatum, H. anatolicum, H. asiaticum and H. dromedarii were known as the most frequent species which were positive for CCHF virus.Conclusion: The status of ticks which were positive for CCHF virus revealed that unlike the most common idea that Hyalomma species are the most important vectors of CCHF virus, other ticks including Rhipicephalus,Haemaphysalis and Dermacentor can be reservoir of this virus; thus, considering geographical distribution, type of host and environmental conditions, different tick control measurements should be carried out in areas with high incidence of CCHF disease.

  15. Vectors of Crimean Congo Hemorrhagic Fever Virus in Iran

    Science.gov (United States)

    Telmadarraiy, Zakkyeh; Chinikar, Sadegh; Vatandoost, Hassan; Faghihi, Faezeh; Hosseini-Chegeni, Asadollah

    2015-01-01

    Background: Ticks are important vectors and reservoirs of Crimean Congo Hemorrhagic Fever (CCHF) virus. Human beings may be infected whenever the normal life cycle of the infected ticks on non-human vertebrate hosts is interrupted by the undesirable presence of humans in the cycle. A total of 26 species of Argasid and Ixodid ticks have been recorded in Iran; including nine Hyalomma, two Rhipicephalus, two Dermacentor, five Haemaphysalis, two Boophilus, one Ixodes and two Argas as well as three Ornithodoros species as blood sucking ectoparasites of livestock and poultries. The present paper reviews tick vectors of CCHF virus in Iran, focusing on the role of ticks in different provinces of Iran using reverse transcription polymerase chain reaction (RT-PCR) assay. Methods: During ten years study, 1054 tick specimens; including two species of Argasidae and 17 species of Ixodidae were examined for their infection to CCHF virus genome. The output of all studies as well as related publications were discussed in the current paper. Results: The results show that Rhipicephalus sanguineus, Hyalomma marginatum, H. anatolicum, H. asiaticum and H. dromedarii were known as the most frequent species which were positive for CCHF virus. Conclusion: The status of ticks which were positive for CCHF virus revealed that unlike the most common idea that Hyalomma species are the most important vectors of CCHF virus, other ticks including Rhipicephalus, Haemaphysalis and Dermacentor can be reservoir of this virus; thus, considering geographical distribution, type of host and environmental conditions, different tick control measurements should be carried out in areas with high incidence of CCHF disease. PMID:26623426

  16. Evaluation of surveillance of dengue fever cases in the public health centre of Putat Jaya based on attribute surveillance

    Directory of Open Access Journals (Sweden)

    Zumaroh Zumaroh

    2015-01-01

    Full Text Available Dengue Hemorrhagic Fever (DHF is a public health problem in the village of Putat Jaya which is an endemic area. Surveilans activity in DHF control program is the most important activity in controlling and monitoring disease progression. The program is expected to achieve incidence rate 55/100.000 population. This study aimed to evaluate the implementation of case surveilans in health centre of putat jaya based on attribute surveillance. Attribute surveillance is an indicator that describes the characteristics of the surveillance system. This research was an evaluation research with descriptive study design. As informants were clinic staff who deal specifically with cases of dengue hemorrhagic fever and laboratory workers. The techniques of data collection by interviews and document study. The variables of this study were simplicity, flexibility, acceptability, sensitivity, positive predictive value, representativeness, timeliness, data quality and data stability. It could be seen from Incidence Rate in 2013 has reached 133/100.00 population. The activity of surveilance in the village of Putat Jaya reviewed from disease contol program management was not succeed into decrease incidence rate of DHF. Therefore, dengue control programs in health centers Putat Jaya need to do cross-sector cooperation and cross-program cooperation, strengthening the case reporting system by way increasing in the utilization of information and communication technology electromedia. Keywords: case surveillance, dengue hemorrhagic fever, evaluation, attribute surveillance, Putat Jaya

  17. Ongoing outbreak of dengue type 1 in the Autonomous Region of Madeira, Portugal: preliminary report.

    Science.gov (United States)

    Sousa, C A; Clairouin, M; Seixas, G; Viveiros, B; Novo, M T; Silva, A C; Escoval, M T; Economopoulou, A

    2012-12-06

    Following the identification of two autochthonous cases of dengue type 1 on 3 October 2012, an outbreak of dengue fever has been reported in Madeira, Portugal. As of 25 November, 1,891 cases have been detected on the island where the vector Aedes aegypti had been established in some areas since 2005. This event represents the first epidemic of dengue fever in Europe since 1928 and concerted control measures have been initiated by local health authorities.

  18. Dengue fever

    Science.gov (United States)

    ... northeastern Australia South and Central America Southeast Asia Sub-Saharan Africa Some parts of the Caribbean (including Puerto Rico ... by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org). URAC's accreditation program is ...

  19. Dengue Fever

    Science.gov (United States)

    ... You Travel Malaria First Aid: Dehydration Blood Transfusions Cholera West Nile Virus First Aid: Vomiting Are Insect ... purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor. © 1995- The Nemours Foundation. All ...

  20. Efficient, trans-complementing packaging systems for chimeric, pseudoinfectious dengue 2/yellow fever viruses

    International Nuclear Information System (INIS)

    Shustov, Alexandr V.; Frolov, Ilya

    2010-01-01

    In our previous studies, we have stated to build a new strategy for developing defective, pseudoinfectious flaviviruses (PIVs) and applying them as a new type of vaccine candidates. PIVs combined the efficiency of live vaccines with the safety of inactivated or subunit vaccines. The results of the present work demonstrate further development of chimeric PIVs encoding dengue virus 2 (DEN2V) glycoproteins and yellow fever virus (YFV)-derived replicative machinery as potential vaccine candidates. The newly designed PIVs have synergistically functioning mutations in the prM and NS2A proteins, which abolish processing of the latter proteins and make the defective viruses capable of producing either only noninfectious, immature and/or subviral DEN2V particles. The PIV genomes can be packaged to high titers into infectious virions in vitro using the NS1-deficient YFV helper RNAs, and both PIVs and helpers can then be passaged as two-component genome viruses at an escalating scale.

  1. Hot spot detection and spatio-temporal dispersion of dengue fever in Hanoi, Vietnam. (Special Issue: Public health in Vietnam: here's the data, where's the action?)

    NARCIS (Netherlands)

    Do Thi Thanh, Toan; Hu, WenBiao; Pham Quang, Thai; Luu Ngoc, Hoat; Wright, P; Martens, P

    2013-01-01

    Introduction: Dengue fever (DF) in Vietnam remains a serious emerging arboviral disease, which generates significant concerns among international health authorities. Incidence rates of DF have increased significantly during the last few years in many provinces and cities, especially Hanoi. The

  2. 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 ...

  3. Dynamic spatiotemporal analysis of indigenous dengue fever at street-level in Guangzhou city, China

    Science.gov (United States)

    Xia, Yao; Zhang, Yingtao; Huang, Xiaodong; Huang, Jiawei; Nie, Enqiong; Jing, Qinlong; Wang, Guoling; Yang, Zhicong; Hu, Wenbiao

    2018-01-01

    Background This study aimed to investigate the spatiotemporal clustering and socio-environmental factors associated with dengue fever (DF) incidence rates at street level in Guangzhou city, China. Methods Spatiotemporal scan technique was applied to identify the high risk region of DF. Multiple regression model was used to identify the socio-environmental factors associated with DF infection. A Poisson regression model was employed to examine the spatiotemporal patterns in the spread of DF. Results Spatial clusters of DF were primarily concentrated at the southwest part of Guangzhou city. Age group (65+ years) (Odd Ratio (OR) = 1.49, 95% Confidence Interval (CI) = 1.13 to 2.03), floating population (OR = 1.09, 95% CI = 1.05 to 1.15), low-education (OR = 1.08, 95% CI = 1.01 to 1.16) and non-agriculture (OR = 1.07, 95% CI = 1.03 to 1.11) were associated with DF transmission. Poisson regression results indicated that changes in DF incidence rates were significantly associated with longitude (β = -5.08, P<0.01) and latitude (β = -1.99, P<0.01). Conclusions The study demonstrated that social-environmental factors may play an important role in DF transmission in Guangzhou. As geographic range of notified DF has significantly expanded over recent years, an early warning systems based on spatiotemporal model with socio-environmental is urgently needed to improve the effectiveness and efficiency of dengue control and prevention. PMID:29561835

  4. Interleukin-10 as a Marker of Disease Progression in Dengue Hemorrhagic Fever

    International Nuclear Information System (INIS)

    Tauseef, A.; Akmal, A.; Umar, N.; Sabir, S.; Sajjad, S.; Zulfiqar, S.

    2016-01-01

    Objective: To evaluate the plasma interleukin-10 (IL-10) levels in patients suffering from dengue hemorrhagic fever between 4 to 7 days of onset of disease and 24 hours after the first sample, to find out the association of plasma IL-10 levels with the outcome. Study Design: Analytical study. Place and Duration of Study: All major hospitals of Lahore, Pakistan, from August to November 2012. Methodology: Participants included 50 registered patients of dengue hemorrhagic fever (DHF) aged between 15 - 50 years. Plasma IL-10 concentrations were measured on above stated day. Outcome was described as recovery and shock. Platelet count and hematocrit percentages were also recorded. Statistical analyses were done using SPSS version 19. A p-value 0.05 was considered significant. Results: Plasma IL-10 levels were found to be raised in DHF patients and were associated with fatal outcome (p=0.004). In recovered DHF patients, plasma IL-10 levels decreased after 24 hours (mean 26.54 ± 16.03 pg/ml) as compared to admission time (mean 74.39 ± 61.69 pg/ml) but in case of DHF patients suffering from shock, plasma IL-10 was found to be higher after 24 hours (mean 87.69 ± 7.77 pg/ml) as compared to levels at admission time (mean 42.56 ± 28.09 pg/ml). ROC curve analysis revealed a change (30 units pg/ml) of plasma IL-10 concentration, within 24 hours of admission, raised from the base line to be 105 times more critical for shock in DHF patients (100 percentage sensitivity and 71.4 percentage specificity, p < 0.001). Conclusion: Elevated plasma IL-10 is a potential predictor of disease severity and fatal outcome in DHF patients. (author)

  5. Socio-demographic determinants of dengue infection during an ...

    African Journals Online (AJOL)

    Dell

    4Southern African Centre for Infectious Disease Surveillance, Africa Centre of Excellence for Infectious Diseases of. Humans and ..... Erlanger, T.E., Keiser, J. & Utzinger, J. (2008) Effect of dengue vector control interventions on ... Dengue fever among hospitalized febrile patients in northern Tanzania. American Journal of.

  6. DENGUE VACCINE, CHALLENGES, DEVELOPMENT AND STRATEGIES

    Directory of Open Access Journals (Sweden)

    Dewi Marbawati

    2014-08-01

    Full Text Available ABSTRAKPenyakit demam Dengue endemik di lebih dari 100 negara di dunia. Obat anti virus Dengue efektif belum ditemukan danpengendalian vektor dinilai kurang efektif, sehingga diperlukan upaya pencegahan dengan vaksinasi. Vaksin Dengue yangideal adalah murah, mencakup 4 serotipe, efektif dalam memberikan kekebalan, cukup diberikan sekali seumur hidup, aman,memberi kekebalan jangka panjang, stabil dalam penyimpanan dan stabil secara genetis (tidak bermutasi. Beberapakandidat vaksin yang telah dan sedang dikembangkan oleh para peneliti di seluruh dunia adalah tetravalent live attenuatedvaccine, vaksin Chimera (ChimeriVax, vaksin subunit dan vaksin DNA. Vaksin Dengue dipandang sebagai pendekatan yangefektif dan berkesinambungan dalam mengendalikan penyakit Dengue. Tahun 2003 telah terbentuk Pediatric DengueVaccine Initiative (PDVI, yaitu sebuah konsorsium internasional yang bergerak dalam advokasi untuk meyakinkanmasyarakat internasional akan penting dan mendesaknya vaksin Dengue. Konsorsium vaksin Dengue Indonesia saat iniberupaya mengembangkan vaksin Dengue dengan menggunakan strain virus lokal.Kata kunci: Dengue, virus, vaksinABSTRACTDengue fever is endemic in more than 100 countries in the world. The effective dengue antiviral drug has not been found yet,and vector control is considered less effective. Prevention program by vaccination is needed. An ideal dengue vaccine shouldbe inexpensive, covering four serotypes (tetravalent, effective in providing immunity, given once a lifetime, safe, stable instorage and genetically. Several vaccine candidates have been and are being developed included attenuated tetravalentvaccine, ChimeriVax, sub- unit vaccines and DNA vaccines. Dengue vaccine is seen as an effective and sustainable approachto controll Dengue infection. In 2003, Pediatric Dengue Vaccine Initiative (PDVI has been formed as an internationalconsortium involved in advocacy to convince the international community about the essence and urgency

  7. Vector competence of Aedes albopictus and Aedes aegypti (Diptera: Culicidae) for the DEN2-FJ10 and DEN2-FJ11 strains of the dengue 2 virus in Fujian, China.

    Science.gov (United States)

    Guo, Xiao-Xia; Li, Chun-Xiao; Zhang, Ying-Mei; Xing, Dan; Dong, Yan-De; Zhang, Heng-Duan; Qin, Cheng-Feng; Zhao, Tong-Yan

    2016-09-01

    Dengue is an acute, emerging, infectious disease transmitted by Aedes mosquitoes that has become a serious global public health problem. The DEN2-FJ10 and DEN2-FJ11 strains of the dengue 2 virus were originally isolated from the serum of a patient with dengue fever in Fujian Province, China, in 1999. Our data provide the first assessment of the vector competence of Aedes mosquitoes with respect to the DEN2-FJ10 and DEN2-FJ11 strains of the dengue virus. There were significant differences in the replication rates of these two viral strains in Aedes albopictus and Aedes aegypti (P0.05). In summary, our results indicate that Ae. albopictus and Ae. aegypti mosquitoes are moderately competent vectors of the DEN2-FJ10 and DEN2-FJ11 strains of the dengue virus and provide the first evidence of the effect of these two viral strains on the vector competence of mosquitoes in China. Copyright © 2016 Elsevier B.V. All rights reserved.

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

    Directory of Open Access Journals (Sweden)

    Martha Anker

    2011-06-01

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

  9. Dengue and Severe Dengue

    Science.gov (United States)

    ... all regions of WHO in recent years. Dengue virus is transmitted by female mosquitoes mainly of the species Aedes aegypti and, to a lesser extent, Ae. albopictus . This mosquito also transmits chikungunya, yellow fever and Zika infection. Dengue is widespread throughout the tropics, with ...

  10. Insecticide Resistance in the Dengue Vector Aedes aegypti from Martinique: Distribution, Mechanisms and Relations with Environmental Factors

    OpenAIRE

    Marcombe , Sébastien; Blanc Mathieu , Romain; Pocquet , Nicolas; Riaz , Muhammad-Asam; Poupardin , Rodolphe; Sélior , Serge; Darriet , Frédéric; Reynaud , Stéphane; Yebakima , André; Corbel , Vincent; David , Jean-Philippe; Chandre , Fabrice

    2012-01-01

    International audience; Dengue is an important mosquito borne viral disease in Martinique Island (French West Indies). The viruses responsible for dengue are transmitted by Aedes aegypti, an indoor day-biting mosquito. The most effective proven method for disease prevention has been by vector control by various chemical or biological means. Unfortunately insecticide resistance has already been observed on the Island and recently showed to significantly reduce the efficacy of vector control in...

  11. The synergistic effect of combined immunization with a DNA vaccine and chimeric yellow fever/dengue virus leads to strong protection against dengue.

    Directory of Open Access Journals (Sweden)

    Adriana S Azevedo

    Full Text Available The dengue envelope glycoprotein (E is the major component of virion surface and its ectodomain is composed of domains I, II and III. This protein is the main target for the development of a dengue vaccine with induction of neutralizing antibodies. In the present work, we tested two different vaccination strategies, with combined immunizations in a prime/booster regimen or simultaneous inoculation with a DNA vaccine (pE1D2 and a chimeric yellow fever/dengue 2 virus (YF17D-D2. The pE1D2 DNA vaccine encodes the ectodomain of the envelope DENV2 protein fused to t-PA signal peptide, while the YF17D-D2 was constructed by replacing the prM and E genes from the 17D yellow fever vaccine virus by those from DENV2. Balb/c mice were inoculated with these two vaccines by different prime/booster or simultaneous immunization protocols and most of them induced a synergistic effect on the elicited immune response, mainly in neutralizing antibody production. Furthermore, combined immunization remarkably increased protection against a lethal dose of DENV2, when compared to each vaccine administered alone. Results also revealed that immunization with the DNA vaccine, regardless of the combination with the chimeric virus, induced a robust cell immune response, with production of IFN-γ by CD8+ T lymphocytes.

  12. Impacto económico del dengue y del dengue hemorrágico en el Estado de Zulia, Venezuela, 1997-2003 Economic impact of dengue and dengue hemorrhagic fever in the State of Zulia, Venezuela, 1997-2003

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    Germán Añez

    2006-05-01

    en Venezuela. A pesar de que el estudio tuvo algunas limitaciones, los resultados demuestran que el dengue constituye un importante problema de salud pública que ocasiona grandes gastos por ausentismo laboral temporal y que afecta considerablemente al desarrollo de la economía regional y nacional.OBJECTIVES: To determine the direct and indirect costs of medical care provided to cases of dengue and dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS between 1997 and 2003 in Zulia State, Venezuela. METHODS: The total number of patients with dengue and DHF/DSS was obtained from records belonging to the Regional Epidemiology Office of the state of Zulia and from reports of cases that were confirmed in the Virology Section of Dr. Americo Negrette’s Clinical Research Institute, Zulia University, Maracaibo, Venezuela, between 1 January 1997 and 31 December 2003. Direct costs included the cost of emergency medical care for all cases and hospital costs for cases with DHF/DSS (cost per bed-day and laboratory expenses. The costs connected to absence from work among patients over 15 years of age and mothers who accompanied their children under 15 years of age comprised the indirect costs, which were adjusted for the proportion of men and women in the labor force. Calculations were based on the minimum yearly wage, and results were given in United States dollars, converted according to each year’s average exchange rate. RESULTS: During the study period, 33 857 cases of dengue and DHF/DSS were seen. Of them, 30 251 (89.35% were cases of dengue, and 3 606 (10.65% were cases of DHF/DSS. Six cases of DHF/DSS died (lethality rate: 0.2 per 100 cases of DHF/DSS. Direct costs were US$ 474 251.70; of these costs, US$ 132 042.30 were spent on emergency medical care and US$ 342 209.40 on the hospital costs of DHF/DSS cases. Indirect costs were US$ 873 825.84 and comprised 64.8% of overall expenditures (US$ 1 348 077.54 connected to this disease during the study years. CONCLUSIONS

  13. Nationwide study of factors associated with public’s willingness to use home self-test kit for dengue fever in Malaysia

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    Li Ping Wong

    2016-08-01

    Full Text Available Abstract Background 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. Methods 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. Results 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 < 0.001, vs. higher perceived barriers to use a home self-testing dengue kit for dengue if the kit was available compared to those with higher perceived barriers to dengue prevention (level of barriers 6-10. Participants with a lower total 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

  14. Presence of a predator image in potential breeding sites and oviposition responses of a dengue vector.

    Science.gov (United States)

    Dieng, Hamady; Satho, Tomomitsu; Suradi, Nur Farrahana Binti; Hakim, Hafijah; Abang, Fatimah; Aliasan, Nur Ezzati; Miake, Fumio; Zuharah, Wan Fatma; Kassim, Nur Faeza A; Majid, Abdul Hafiz A; Fadzly, Nik; Vargas, Ronald E Morales; Morales, Noppawan P; Noweg, Gabriel Tonga

    2017-12-01

    In dengue vector control, attempts to minimize or replace the use of pesticides have mostly involved use of predators, but success has been severely impeded by difficulties associated with financial and environmental costs, predator mass production, and persistence in target habitats. Visual deterrents have been used successfully to control animal pests, in some cases in an effort to replace pesticide use. Despite evidence that visual signals are crucial in site choice for egg deposition by dengue vectors, and that female mosquitoes respond to artificial predation, the role of predator intimidation as it affects the oviposition behavior of dengue vectors remains largely unexplored. Here, we examined the oviposition responses of Aedes aegypti exposed to various mosquito predator pictures. Gravid females were presented with equal opportunities to oviposit in two cups with predator images [Toxorhynchites splendens-TXI, Goldfish (Carassius auratus)-small (SFI) and large (LFI) and Tx. splendens+Goldfish-TXFI] and two others without pictures. Differences in egg deposition were examined between sites with and without these images. When given a chance to oviposit in cups with and without TXI, Ae. aegypti females were similarly attracted to both sites. When provided an opportunity to oviposit in cups displaying pictures of fish (SFI or LFI) and blank cups, egg deposition rates were much lower in the fish picture sites. Females showed a preference for blank cups over TXFI for egg deposition. They also equally avoided cups with pictures of fish, regardless of the size of the picture. Our results indicate that the presence of images of goldfish and their association with Tx. larvae significantly reduced egg deposition by Ae. aegypti, and this was not the case with the predatory larvae alone. The observations that the images of natural predators can repel gravid females of a dengue vector provide novel possibilities to develop effective and inexpensive alternative tools to

  15. Spectrum of findings on magnetic resonance imaging of the brain in patients with neurological manifestations of dengue fever

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    Tejeshwar Singh Jugpal

    Full Text Available Abstract Objective: To describe the spectrum of magnetic resonance imaging (MRI findings in patients with neurological manifestations of dengue. Materials and Methods: We included nine patients with dengue fever (three females and six males; age range, 9–30 years, all of whom presented with neurological manifestations. The MRI examinations, performed in 1.5 T or 3 T scanners, included T1-weighted, T2-weighted, and fluid-attenuated inversion recovery (FLAIR sequences. Diffusion-weighted imaging with apparent diffusion coefficient mapping was also employed. Fast low-angle shot and susceptibility-weighted gradient-recalled echo sequences, as well as contrast-enhanced T1-weighted scans, were also obtained in order to assess parenchymal enhancement. MRI scans were analyzed for lesion distribution and imaging features. Results: All patients showed areas of altered signal intensity that appeared as hyperintensity on T2-weighted and FLAIR sequences. The most commonly affected site was the basal ganglia-thalamus complex. Other affected sites were the cerebellum, cerebral cortex, white matter, and brainstem. In all cases, we observed patchy areas of restricted diffusion and focal areas of hemorrhage. Conclusion: Dengue encephalitis commonly affects the basal ganglia, thalamus, cerebellum, cerebral cortex, and white matter. Therefore, MRI should be an indispensable part of the evaluation of patients with neurological complications of dengue fever.

  16. In silico design of fragment-based drug targeting host processing α-glucosidase i for dengue fever

    Science.gov (United States)

    Toepak, E. P.; Tambunan, U. S. F.

    2017-02-01

    Dengue is a major health problem in the tropical and sub-tropical regions. The development of antiviral that targeting dengue’s host enzyme can be more effective and efficient treatment than the viral enzyme. Host enzyme processing α-glucosidase I has an important role in the maturation process of dengue virus envelope glycoprotein. The inhibition of processing α-glucosidase I can become a promising target for dengue fever treatment. The antiviral approach using in silico fragment-based drug design can generate drug candidates with high binding affinity. In this research, 198.621 compounds were obtained from ZINC15 Biogenic Database. These compounds were screened to find the favorable fragments according to Rules of Three and pharmacological properties. The screening fragments were docked into the active site of processing α-glucosidase I. The potential fragment candidates from the molecular docking simulation were linked with castanospermine (CAST) to generate ligands with a better binding affinity. The Analysis of ligand - enzyme interaction showed ligands with code LRS 22, 28, and 47 have the better binding free energy than the standard ligand. Ligand LRS 28 (N-2-4-methyl-5-((1S,3S,6S,7R,8R,8aR)-1,6,7,8-tetrahydroxyoctahydroindolizin-3-yl) pentyl) indolin-1-yl) propionamide) itself among the other ligands has the lowest binding free energy. Pharmacological properties prediction also showed the ligands LRS 22, 28, and 47 can be promising as the dengue fever drug candidates.

  17. Climate and dengue transmission: evidence and implications.

    Science.gov (United States)

    Morin, Cory W; Comrie, Andrew C; Ernst, Kacey

    2013-01-01

    Climate influences dengue ecology by affecting vector dynamics, agent development, and mosquito/human interactions. Although these relationships are known, the impact climate change will have on transmission is unclear. Climate-driven statistical and process-based models are being used to refine our knowledge of these relationships and predict the effects of projected climate change on dengue fever occurrence, but results have been inconsistent. We sought to identify major climatic influences on dengue virus ecology and to evaluate the ability of climate-based dengue models to describe associations between climate and dengue, simulate outbreaks, and project the impacts of climate change. We reviewed the evidence for direct and indirect relationships between climate and dengue generated from laboratory studies, field studies, and statistical analyses of associations between vectors, dengue fever incidence, and climate conditions. We assessed the potential contribution of climate-driven, process-based dengue models and provide suggestions to improve their performance. Relationships between climate variables and factors that influence dengue transmission are complex. A climate variable may increase dengue transmission potential through one aspect of the system while simultaneously decreasing transmission potential through another. This complexity may at least partly explain inconsistencies in statistical associations between dengue and climate. Process-based models can account for the complex dynamics but often omit important aspects of dengue ecology, notably virus development and host-species interactions. Synthesizing and applying current knowledge of climatic effects on all aspects of dengue virus ecology will help direct future research and enable better projections of climate change effects on dengue incidence.

  18. Role of Ultrasonography ( and ldquo;Honeycomb Sign and rdquo; in Early Detection of Dengue Hemorrhagic Fever

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    Sudhir Sachar

    2013-02-01

    Conclusions: Abdominal emergency USG can be used as a first-line imaging modality in patients with suspected DHF to detect early signs that are suggestive of the disease prior to obtaining serologic confirmation test results, especially in a dengue fever epidemic area. Also, reducing GB wall thickness can be used as a prognostic sign in cases of DHF. [Arch Clin Exp Surg 2013; 2(1.000: 38-42

  19. Carnival or football, is there a real risk for acquiring dengue fever in Brazil during holidays seasons?

    Science.gov (United States)

    Aguiar, Maíra; Rocha, Filipe; Pessanha, José Eduardo Marques; Mateus, Luis; Stollenwerk, Nico

    2015-02-01

    More than 600,000 football fans, coming from all over the world, were expected to visit Brazil during the FIFA World Cup 2014. International travel can become a public health problem when the visitors start to become sick, needing medical intervention and eventually hospitalization. The occurrence of dengue fever infections in Brazil is persistent and has been increasing since the 1980s, and the health authorities were expected to take preventive measures and to warn the visitors about the risks during the tournament period. Before the World Cup started, studies have been published stating that dengue could be a significant problem in some of the Brazilian cities hosting the games. These conclusions were taken after a brief observation of the available data, analyzing its mean and standard deviation only, or based on seasonal climate forecasts, causing alarm for the world cup in Brazil. Here, with a more careful data analysis, we show that the seasonality of the disease plays a major role in dengue transmission. The density of dengue cases in Brazil is residual during winter in the Southern hemisphere (mid June to mid September) and the fans of football were not likely to get dengue during the tournament period.

  20. Improving Dengue Virus Capture Rates in Humans and Vectors in Kamphaeng Phet Province, Thailand, Using an Enhanced Spatiotemporal Surveillance Strategy

    Science.gov (United States)

    2015-05-18

    flaviviruses (e.g., Japanese encephalitis and yellow fever viruses) have on DENV transmission and the observed clinical phenotypes following...Initiate case identification and evaluation. KAVRU provides the KPPPH dengue diagnostic research assays for patients presenting with fever or history of...Scott RM, Thomas SJ, Hoke CH Jr, 2013. A model international partnership for community-based research on vaccine -preventable diseases: the Kamphaeng

  1. OSBPL10, RXRA and lipid metabolism confer African-ancestry protection against dengue haemorrhagic fever in admixed Cubans.

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    Beatriz Sierra

    2017-02-01

    Full Text Available Ethnic groups can display differential genetic susceptibility to infectious diseases. The arthropod-born viral dengue disease is one such disease, with empirical and limited genetic evidence showing that African ancestry may be protective against the haemorrhagic phenotype. Global ancestry analysis based on high-throughput genotyping in admixed populations can be used to test this hypothesis, while admixture mapping can map candidate protective genes. A Cuban dengue fever cohort was genotyped using a 2.5 million SNP chip. Global ancestry was ascertained through ADMIXTURE and used in a fine-matched corrected association study, while local ancestry was inferred by the RFMix algorithm. The expression of candidate genes was evaluated by RT-PCR in a Cuban dengue patient cohort and gene set enrichment analysis was performed in a Thai dengue transcriptome. OSBPL10 and RXRA candidate genes were identified, with most significant SNPs placed in inferred weak enhancers, promoters and lncRNAs. OSBPL10 had significantly lower expression in Africans than Europeans, while for RXRA several SNPs may differentially regulate its transcription between Africans and Europeans. Their expression was confirmed to change through dengue disease progression in Cuban patients and to vary with disease severity in a Thai transcriptome dataset. These genes interact in the LXR/RXR activation pathway that integrates lipid metabolism and immune functions, being a key player in dengue virus entrance into cells, its replication therein and in cytokine production. Knockdown of OSBPL10 expression in THP-1 cells by two shRNAs followed by DENV2 infection tests led to a significant reduction in DENV replication, being a direct functional proof that the lower OSBPL10 expression profile in Africans protects this ancestry against dengue disease.

  2. Effectiveness of individual health education on the practice of dengue fever prevention in an urban area of Puducherry, India

    Directory of Open Access Journals (Sweden)

    Suman Saurabh

    2014-12-01

    Full Text Available Background: Prevention of breeding of Aedes mosquito is an effective method for dengue control. Practice of source reduction to prevent breeding depends on the knowledge of the community, which can be improved by health education. Objectives: Our objective was to ascertain the knowledge and practice of the community regarding dengue and its prevention, and to assess the effectiveness of individual health education on practice of dengue prevention. Methodology: In urban service area of JIPMER, using Street-wise cluster sampling pre and post intervention data collection was done. Intervention was “Individual health education on the practice of dengue prevention”. Main outcome measures were Awareness and practice regarding dengue prevention. McNemar’s test was used in the analysis. Results: A total of 351 respondents were studied of whom 89% knew that dengue was spread by mosquitoes. Only one-fourths knew about the correct biting time and breeding condition of Aedes mosquitoes. Practice regarding draining of unused tyres, coolers, flower vases, disposal of coconut shells and keeping unused flower pots upturned were found to improve significantly after health education. Conclusions: Individual health education was effective in improving the practice of source reduction in a community with poor knowledge of vector biting and breeding habits.

  3. Exploring the molecular basis of insecticide resistance in the dengue vector Aedes aegypti: a case study in Martinique Island (French West Indies

    Directory of Open Access Journals (Sweden)

    Yébakima André

    2009-10-01

    Full Text Available Abstract Background The yellow fever mosquito Aedes aegypti is a major vector of dengue and hemorrhagic fevers, causing up to 100 million dengue infections every year. As there is still no medicine and efficient vaccine available, vector control largely based on insecticide treatments remains the only method to reduce dengue virus transmission. Unfortunately, vector control programs are facing operational challenges with mosquitoes becoming resistant to commonly used insecticides. Resistance of Ae. aegypti to chemical insecticides has been reported worldwide and the underlying molecular mechanisms, including the identification of enzymes involved in insecticide detoxification are not completely understood. Results The present paper investigates the molecular basis of insecticide resistance in a population of Ae. aegypti collected in Martinique (French West Indies. Bioassays with insecticides on adults and larvae revealed high levels of resistance to organophosphate and pyrethroid insecticides. Molecular screening for common insecticide target-site mutations showed a high frequency (71% of the sodium channel 'knock down resistance' (kdr mutation. Exposing mosquitoes to detoxification enzymes inhibitors prior to bioassays induced a significant increased susceptibility of mosquitoes to insecticides, revealing the presence of metabolic-based resistance mechanisms. This trend was biochemically confirmed by significant elevated activities of cytochrome P450 monooxygenases, glutathione S-transferases and carboxylesterases at both larval and adult stages. Utilization of the microarray Aedes Detox Chip containing probes for all members of detoxification and other insecticide resistance-related enzymes revealed the significant constitutive over-transcription of multiple detoxification genes at both larval and adult stages. The over-transcription of detoxification genes in the resistant strain was confirmed by using real-time quantitative RT

  4. Exploring the molecular basis of insecticide resistance in the dengue vector Aedes aegypti: a case study in Martinique Island (French West Indies).

    Science.gov (United States)

    Marcombe, Sébastien; Poupardin, Rodolphe; Darriet, Frederic; Reynaud, Stéphane; Bonnet, Julien; Strode, Clare; Brengues, Cecile; Yébakima, André; Ranson, Hilary; Corbel, Vincent; David, Jean-Philippe

    2009-10-26

    The yellow fever mosquito Aedes aegypti is a major vector of dengue and hemorrhagic fevers, causing up to 100 million dengue infections every year. As there is still no medicine and efficient vaccine available, vector control largely based on insecticide treatments remains the only method to reduce dengue virus transmission. Unfortunately, vector control programs are facing operational challenges with mosquitoes becoming resistant to commonly used insecticides. Resistance of Ae. aegypti to chemical insecticides has been reported worldwide and the underlying molecular mechanisms, including the identification of enzymes involved in insecticide detoxification are not completely understood. The present paper investigates the molecular basis of insecticide resistance in a population of Ae. aegypti collected in Martinique (French West Indies). Bioassays with insecticides on adults and larvae revealed high levels of resistance to organophosphate and pyrethroid insecticides. Molecular screening for common insecticide target-site mutations showed a high frequency (71%) of the sodium channel 'knock down resistance' (kdr) mutation. Exposing mosquitoes to detoxification enzymes inhibitors prior to bioassays induced a significant increased susceptibility of mosquitoes to insecticides, revealing the presence of metabolic-based resistance mechanisms. This trend was biochemically confirmed by significant elevated activities of cytochrome P450 monooxygenases, glutathione S-transferases and carboxylesterases at both larval and adult stages. Utilization of the microarray Aedes Detox Chip containing probes for all members of detoxification and other insecticide resistance-related enzymes revealed the significant constitutive over-transcription of multiple detoxification genes at both larval and adult stages. The over-transcription of detoxification genes in the resistant strain was confirmed by using real-time quantitative RT-PCR. These results suggest that the high level of

  5. Diabetes with hypertension as risk factors for adult dengue hemorrhagic fever in a predominantly dengue serotype 2 epidemic: a case control study.

    Directory of Open Access Journals (Sweden)

    Junxiong Pang

    Full Text Available BACKGROUND: Dengue hemorrhagic fever (DHF is a severe form of dengue, characterized by bleeding and plasma leakage. A number of DHF risk factors had been suggested. However, these risk factors may not be generalized to all populations and epidemics for screening and clinical management of patients at risk of developing DHF. This study explored demographic and comorbidity risk factors for DHF in adult dengue epidemics in Singapore in year 2006 (predominantly serotype 1 and in year 2007-2008 (predominantly serotype 2. METHODS: A retrospective case-control study was conducted with 149 DHF and 326 dengue fever (DF patients from year 2006, and 669 DHF and 1,141 DF patients from year 2007-2008. Demographic and reported comorbidity data were collected from patients previously. We performed multivariate logistic regression to assess the association between DHF and demographic and co-morbidities for year 2006 and year 2007-2008, respectively. RESULTS: Only Chinese (adjusted odds ratio [AOR] = 1.90; 95% confidence interval [CI]: 1.01-3.56 was independently associated with DHF in year 2006. In contrast, age groups of 30-39 years (AOR = 1.41; 95% CI:1.09-1.81, 40-49 years (AOR = 1.34; 95% CI:1.09-1.81, female (AOR = 1.57; 95% CI:1.28-1.94, Chinese (AOR = 1.67; 95% CI:1.24-2.24, diabetes (AOR = 1.78; 95% CI:1.06-2.97, and diabetes with hypertension (AOR = 2.16; 95%CI:1.18-3.96 were independently associated with DHF in year 2007-2008. Hypertension was proposed to have effect modification on the risk of DHF outcome in dengue patients with diabetes. Chinese who had diabetes with hypertension had 2.1 (95% CI:1.07-4.12 times higher risk of DHF compared with Chinese who had no diabetes and no hypertension. CONCLUSIONS: Adult dengue patients in Singapore who were 30-49 years, Chinese, female, had diabetes or diabetes with hypertension were at greater risk of developing DHF during epidemic of predominantly serotype 2. These risk factors

  6. [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.

  7. Heterogeneous Feeding Patterns of the Dengue Vector, Aedes aegypti, on Individual Human Hosts in Rural Thailand

    Science.gov (United States)

    Harrington, Laura C.; Fleisher, Andrew; Ruiz-Moreno, Diego; Vermeylen, Francoise; Wa, Chrystal V.; Poulson, Rebecca L.; Edman, John D.; Clark, John M.; Jones, James W.; Kitthawee, Sangvorn; Scott, Thomas W.

    2014-01-01

    Background Mosquito biting frequency and how bites are distributed among different people can have significant epidemiologic effects. An improved understanding of mosquito vector-human interactions would refine knowledge of the entomological processes supporting pathogen transmission and could reveal targets for minimizing risk and breaking pathogen transmission cycles. Methodology and principal findings We used human DNA blood meal profiling of the dengue virus (DENV) vector, Aedes aegypti, to quantify its contact with human hosts and to infer epidemiologic implications of its blood feeding behavior. We determined the number of different people bitten, biting frequency by host age, size, mosquito age, and the number of times each person was bitten. Of 3,677 engorged mosquitoes collected and 1,186 complete DNA profiles, only 420 meals matched people from the study area, indicating that Ae. aegypti feed on people moving transiently through communities to conduct daily business. 10–13% of engorged mosquitoes fed on more than one person. No biting rate differences were detected between high- and low-dengue transmission seasons. We estimate that 43–46% of engorged mosquitoes bit more than one person within each gonotrophic cycle. Most multiple meals were from residents of the mosquito collection house or neighbors. People ≤25 years old were bitten less often than older people. Some hosts were fed on frequently, with three hosts bitten nine times. Interaction networks for mosquitoes and humans revealed biologically significant blood feeding hotspots, including community marketplaces. Conclusion and significance High multiple-feeding rates and feeding on community visitors are likely important features in the efficient transmission and rapid spread of DENV. These results help explain why reducing vector populations alone is difficult for dengue prevention and support the argument for additional studies of mosquito feeding behavior, which when integrated with a

  8. Heterogeneous feeding patterns of the dengue vector, Aedes aegypti, on individual human hosts in rural Thailand.

    Directory of Open Access Journals (Sweden)

    Laura C Harrington

    2014-08-01

    Full Text Available Mosquito biting frequency and how bites are distributed among different people can have significant epidemiologic effects. An improved understanding of mosquito vector-human interactions would refine knowledge of the entomological processes supporting pathogen transmission and could reveal targets for minimizing risk and breaking pathogen transmission cycles.We used human DNA blood meal profiling of the dengue virus (DENV vector, Aedes aegypti, to quantify its contact with human hosts and to infer epidemiologic implications of its blood feeding behavior. We determined the number of different people bitten, biting frequency by host age, size, mosquito age, and the number of times each person was bitten. Of 3,677 engorged mosquitoes collected and 1,186 complete DNA profiles, only 420 meals matched people from the study area, indicating that Ae. aegypti feed on people moving transiently through communities to conduct daily business. 10-13% of engorged mosquitoes fed on more than one person. No biting rate differences were detected between high- and low-dengue transmission seasons. We estimate that 43-46% of engorged mosquitoes bit more than one person within each gonotrophic cycle. Most multiple meals were from residents of the mosquito collection house or neighbors. People ≤ 25 years old were bitten less often than older people. Some hosts were fed on frequently, with three hosts bitten nine times. Interaction networks for mosquitoes and humans revealed biologically significant blood feeding hotspots, including community marketplaces.High multiple-feeding rates and feeding on community visitors are likely important features in the efficient transmission and rapid spread of DENV. These results help explain why reducing vector populations alone is difficult for dengue prevention and support the argument for additional studies of mosquito feeding behavior, which when integrated with a greater understanding of human behavior will refine estimates of

  9. Community effectiveness of pyriproxyfen as a dengue vector control method: A systematic review.

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    Dorit Maoz

    2017-07-01

    Full Text Available Vector control is the only widely utilised method for primary prevention and control of dengue. The use of pyriproxyfen may be promising, and autodissemination approach may reach hard to reach breeding places. It offers a unique mode of action (juvenile hormone mimic and as an additional tool for the management of insecticide resistance among Aedes vectors. However, evidence of efficacy and community effectiveness (CE remains limited.The aim of this systematic review is to compile and analyse the existing literature for evidence on the CE of pyriproxyfen as a vector control method for reducing Ae. aegypti and Ae. albopictus populations and thereby human dengue transmission.Systematic search of PubMed, Embase, Lilacs, Cochrane library, WHOLIS, Web of Science, Google Scholar as well as reference lists of all identified studies. Removal of duplicates, screening of abstracts and assessment for eligibility of the remaining studies followed. Relevant data were extracted, and a quality assessment conducted. Results were classified into four main categories of how pyriproxyfen was applied: - 1 container treatment, 2 fumigation, 3 auto-dissemination or 4 combination treatments,-and analysed with a view to their public health implication.Out of 745 studies 17 studies were identified that fulfilled all eligibility criteria. The results show that pyriproxyfen can be effective in reducing the numbers of Aedes spp. immatures with different methods of application when targeting their main breeding sites. However, the combination of pyriproxyfen with a second product increases efficacy and/or persistence of the intervention and may also slow down the development of insecticide resistance. Open questions concern concentration and frequency of application in the various treatments. Area-wide ultra-low volume treatment with pyriproxyfen currently lacks evidence and cannot be recommended. Community participation and acceptance has not consistently been successful

  10. Community effectiveness of pyriproxyfen as a dengue vector control method: A systematic review.

    Science.gov (United States)

    Maoz, Dorit; Ward, Tara; Samuel, Moody; Müller, Pie; Runge-Ranzinger, Silvia; Toledo, Joao; Boyce, Ross; Velayudhan, Raman; Horstick, Olaf

    2017-07-01

    Vector control is the only widely utilised method for primary prevention and control of dengue. The use of pyriproxyfen may be promising, and autodissemination approach may reach hard to reach breeding places. It offers a unique mode of action (juvenile hormone mimic) and as an additional tool for the management of insecticide resistance among Aedes vectors. However, evidence of efficacy and community effectiveness (CE) remains limited. The aim of this systematic review is to compile and analyse the existing literature for evidence on the CE of pyriproxyfen as a vector control method for reducing Ae. aegypti and Ae. albopictus populations and thereby human dengue transmission. Systematic search of PubMed, Embase, Lilacs, Cochrane library, WHOLIS, Web of Science, Google Scholar as well as reference lists of all identified studies. Removal of duplicates, screening of abstracts and assessment for eligibility of the remaining studies followed. Relevant data were extracted, and a quality assessment conducted. Results were classified into four main categories of how pyriproxyfen was applied: - 1) container treatment, 2) fumigation, 3) auto-dissemination or 4) combination treatments,-and analysed with a view to their public health implication. Out of 745 studies 17 studies were identified that fulfilled all eligibility criteria. The results show that pyriproxyfen can be effective in reducing the numbers of Aedes spp. immatures with different methods of application when targeting their main breeding sites. However, the combination of pyriproxyfen with a second product increases efficacy and/or persistence of the intervention and may also slow down the development of insecticide resistance. Open questions concern concentration and frequency of application in the various treatments. Area-wide ultra-low volume treatment with pyriproxyfen currently lacks evidence and cannot be recommended. Community participation and acceptance has not consistently been successful and needs to

  11. Pupal productivity of dengue vectors in Kolkata, India: implications for vector management

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    Soumyajit Banerjee

    2013-01-01

    Interpretation & conclusions: Pupal productivity of Aedes mosquitoes in Kolkata differed in terms of the type of the larval habitats with the immature density affecting the body size of the adults. This habitat-based study is a pioneer effort considering Kolkata and calls for a management plan for source reduction of these habitats to minimize Aedes mosquitoes and thus potential risk of dengue.

  12. Knowledge and practices related to dengue and its vector: a community-based study from Southeast Brazil.

    Science.gov (United States)

    Alves, Adorama Candido; Fabbro, Amaury Lelis Dal; Passos, Afonso Dinis Costa; Carneiro, Ariadne Fernanda Tesarin Mendes; Jorge, Tatiane Martins; Martinez, Edson Zangiacomi

    2016-04-01

    This study investigated the knowledge of users of primary healthcare services living in Ribeirão Preto, Brazil, about dengue and its vector. A cross-sectional survey of 605 people was conducted following a major dengue outbreak in 2013. Participants with higher levels of education were more likely to identify correctly the vector of the disease. The results emphasize the relevance of health education programs, the continuous promotion of educational campaigns in the media, the role of the television as a source of information, and the importance of motivating the population to control the vector.

  13. Knowledge and practices related to dengue and its vector: a community-based study from Southeast Brazil

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    Adorama Candido Alves

    2016-04-01

    Full Text Available Abstract INTRODUCTION: This study investigated the knowledge of users of primary healthcare services living in Ribeirão Preto, Brazil, about dengue and its vector. METHODS: A cross-sectional survey of 605 people was conducted following a major dengue outbreak in 2013. RESULTS: Participants with higher levels of education were more likely to identify correctly the vector of the disease. CONCLUSIONS: The results emphasize the relevance of health education programs, the continuous promotion of educational campaigns in the media, the role of the television as a source of information, and the importance of motivating the population to control the vector.

  14. "We need people to collaborate together against this disease": A qualitative exploration of perceptions of dengue fever control in caregivers' of children under 5 years, in the Peruvian Amazon.

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    Amy L Frank

    2017-09-01

    Full Text Available Dengue Fever presents a significant and growing burden of disease to endemic countries, where children are at particular risk. Worldwide, no effective anti-viral treatment has been identified, thus vector control is key for disease prevention, particularly in Peru where no vaccine is currently available. This qualitative study aimed to explore the perceptions of dengue control in caregivers' of children under 5 years in Peru, to help direct future mosquito control programmes and strategy.Eighteen semi-structured interviews were conducted in one health centre in Iquitos, Peru. Interviews were audio-recorded, transcribed and translated by an independent translator. Data were analysed using an inductive thematic approach.Three core analytic themes were interpreted: (1 awareness of dengue and its control, (2 perceived susceptibility of children, rural riverside communities and city inhabitants, and (3 perceived responsibility of vector control. Participants were aware of dengue symptoms, transmission and larvae eradication strategies. Misconceptions about the day-time biting behaviour of the Aedes aegypti mosquito and confusion with other mosquito-borne diseases influenced preventative practice. Community-wide lack of cooperation was recognised as a key barrier. This was strengthened by attitudes that the government or health centre were responsible for dengue control and a belief that the disease cannot be prevented through individual actions. Participants felt powerless to prevent dengue due to assumed inevitability of infection and lack of faith in preventative practices. However, children and rural communities were believed to be most vulnerable.Perceptions of dengue control amongst caregivers to under 5's were important in shaping their likelihood to participate in preventative practices. There is a need to address the perceived lack of community cooperation through strategies creating a sense of ownership of community control and enhancing

  15. Expression profile of genes during resistance reversal in a temephos selected strain of the dengue vector, Aedes aegypti.

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    Clare Strode

    Full Text Available BACKGROUND: The mosquito Aedes aegypti is one of the most important disease vectors because it transmits two major arboviruses, dengue and yellow fever, which cause significant global morbidity and mortality. Chemical insecticides form the cornerstone of vector control. The organophosphate temephos a larvicide recommended by WHO for controlling Ae. aegypti, however, resistance to this compound has been reported in many countries, including Brazil. METHODOLOGY/PRINCIPAL FINDINGS: The aim of this study was to identify genes implicated in metabolic resistance in an Ae. aegypti temephos resistant strain, named RecR, through microarray analysis. We utilized a custom 'Ae. aegypti detox chip' and validated microarray data through RT-PCR comparing susceptible and resistant individuals. In addition, we analyzed gene expression in 4(th instar larvae from a reversed susceptible strain (RecRev, exposed and unexposed to temephos. The results obtained revealed a set of 13 and 6 genes significantly over expressed in resistant adult mosquitoes and larvae, respectively. One of these genes, the cytochrome P450 CYP6N12, was up-regulated in both stages. RT-PCR confirmed the microarray results and, additionally, showed no difference in gene expression between temephos exposed and unexposed RecRev mosquitoes. This suggested that the differences in the transcript profiles among the strains are heritable due to a selection process and are not caused by immediate insecticide exposure. Reversal of temephos resistance was demonstrated and, importantly, there was a positive correlation between a decrease in the resistance ratio and an accompanying decrease in the expression levels of previously over expressed genes. Some of the genes identified here have also been implicated in metabolic resistance in other mosquito species and insecticide resistant populations of Ae. aegypti. CONCLUSIONS/SIGNIFICANCE: The identification of gene expression signatures associated to

  16. 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.

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

    Science.gov (United States)

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

    2014-05-01

    The emergence and re-emergence of disease epidemics is a complex question that may be influenced by diverse factors, including the space-time dynamics of human populations, environmental conditions, and associated uncertainties. This study proposes a stochastic framework to integrate space-time dynamics in the form of a Susceptible-Infected-Recovered (SIR) model, together with uncertain disease observations, into a Bayesian maximum entropy (BME) framework. The resulting model (BME-SIR) can be used to predict space-time disease spread. Specifically, it was applied to obtain a space-time prediction of the dengue fever (DF) epidemic that took place in Kaohsiung City (Taiwan) during 2002. In implementing the model, the SIR parameters were continually updated and information on new cases of infection was incorporated. The results obtained show that the proposed model is rigorous to user-specified initial values of unknown model parameters, that is, transmission and recovery rates. In general, this model provides a good characterization of the spatial diffusion of the DF epidemic, especially in the city districts proximal to the location of the outbreak. Prediction performance may be affected by various factors, such as virus serotypes and human intervention, which can change the space-time dynamics of disease diffusion. The proposed BME-SIR disease prediction model can provide government agencies with a valuable reference for the timely identification, control, and prevention of DF spread in space and time. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Is There a Risk of Yellow Fever Virus Transmission in South Asian Countries with Hyperendemic Dengue?

    Science.gov (United States)

    Agampodi, Suneth B.; Wickramage, Kolitha

    2013-01-01

    The fact that yellow fever (YF) has never occurred in Asia remains an “unsolved mystery” in global health. Most countries in Asia with high Aedes aegypti mosquito density are considered “receptive” for YF transmission. Recently, health officials in Sri Lanka issued a public health alert on the potential spread of YF from a migrant group from West Africa. We performed an extensive review of literature pertaining to the risk of YF in Sri Lanka/South Asian region to understand the probability of actual risk and assist health authorities to form evidence informed public health policies/practices. Published data from epidemiological, historical, biological, molecular, and mathematical models were harnessed to assess the risk of YF in Asia. Using this data we examine a number of theories proposed to explain lack of YF in Asia. Considering the evidence available, we conclude that the probable risk of local transmission of YF is extremely low in Sri Lanka and for other South Asian countries despite a high Aedes aegypti density and associated dengue burden. This does not however exclude the future possibility of transmission in Asia, especially considering the rapid influx travelers from endemic areas, as we report, arriving in Sri Lanka. PMID:24367789

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

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    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.

  20. Climate Change and the Arboviruses: Lessons from the Evolution of the Dengue and Yellow Fever Viruses.

    Science.gov (United States)

    Tabachnick, Walter J

    2016-09-29

    The impact of anticipated changes in global climate on the arboviruses and the diseases they cause poses a significant challenge for public health. The past evolution of the dengue and yellow fever viruses provides clues about the influence of changes in climate on their future evolution. The evolution of both viruses has been influenced by virus interactions involving the mosquito species and the primate hosts involved in virus transmission, and by their domestic and sylvatic cycles. Information is needed on how viral genes in general influence phenotypic variance for important viral functions. Changes in global climate will alter the interactions of mosquito species with their primate hosts and with the viruses in domestic cycles, and greater attention should be paid to the sylvatic cycles. There is great danger for the evolution of novel viruses, such as new serotypes, that could compromise vaccination programs and jeopardize public health. It is essential to understand (a) both sylvatic and domestic cycles and (b) the role of virus genetic and environmental variances in shaping virus phenotypic variance to more fully assess the impact of global climate change.

  1. Knowledge, attitude and preventive practices regarding dengue fever in rural areas of Yemen.

    Science.gov (United States)

    Saied, Khaled G; Al-Taiar, Abdullah; Altaire, Abdulrahman; Alqadsi, Ala; Alariqi, Enas F; Hassaan, Maha

    2015-11-01

    In recent years there have been several reports of outbreaks of dengue fever (DF) in Yemen. This study aimed to describe the prevailing knowledge, attitude and preventive practices regarding DF, and to investigate the factors associated with poor preventive practices in rural areas of Yemen. A population-based, cross-sectional study was conducted on 804 randomly selected heads of household. A pretested, structured questionnaire was administered through face-to-face interviews. Logistic regression was used to investigate factors independently associated with poor practice. Out of 804 participants, 753 (93.7%) were aware of the symptoms of DF and 671 (83.4%) knew that DF was transmitted by mosquito bites. Only 420 (52.2%) knew that direct person-to-person transmission was not possible. Furthermore, 205 (25.5%) thought that someone with DF should be avoided and 460 (57.2%) thought the elimination of breeding sites was the responsibility of health authorities. Poor knowledge of DF and a low level of education were significantly associated with poor preventive practices. In rural areas of Yemen, people have a vague understanding of DF transmission and a negative attitude towards preventative practices. Efforts should be made to correct misconceptions about transmission of the disease and to highlight the importance of community participation in control activities. © The Author 2015. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  2. Re-assess Vector Indices Threshold as an Early Warning Tool for Predicting Dengue Epidemic in a Dengue Non-endemic Country.

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    Fong-Shue Chang

    Full Text Available Despite dengue dynamics being driven by complex interactions between human hosts, mosquito vectors and viruses that are influenced by climate factors, an operational model that will enable health authorities to anticipate the outbreak risk in a dengue non-endemic area has not been developed. The objectives of this study were to evaluate the temporal relationship between meteorological variables, entomological surveillance indices and confirmed dengue cases; and to establish the threshold for entomological surveillance indices including three mosquito larval indices [Breteau (BI, Container (CI and House indices (HI] and one adult index (AI as an early warning tool for dengue epidemic.Epidemiological, entomological and meteorological data were analyzed from 2005 to 2012 in Kaohsiung City, Taiwan. The successive waves of dengue outbreaks with different magnitudes were recorded in Kaohsiung City, and involved a dominant serotype during each epidemic. The annual indigenous dengue cases usually started from May to June and reached a peak in October to November. Vector data from 2005-2012 showed that the peak of the adult mosquito population was followed by a peak in the corresponding dengue activity with a lag period of 1-2 months. Therefore, we focused the analysis on the data from May to December and the high risk district, where the inspection of the immature and mature mosquitoes was carried out on a weekly basis and about 97.9% dengue cases occurred. The two-stage model was utilized here to estimate the risk and time-lag effect of annual dengue outbreaks in Taiwan. First, Poisson regression was used to select the optimal subset of variables and time-lags for predicting the number of dengue cases, and the final results of the multivariate analysis were selected based on the smallest AIC value. Next, each vector index models with selected variables were subjected to multiple logistic regression models to examine the accuracy of predicting the

  3. Declining Prevalence of Disease Vectors Under Climate Change

    DEFF Research Database (Denmark)

    Escobar, Luis E.; Romero-Alvarez, Daniel; Leon, Renato

    2016-01-01

    More than half of the world population is at risk of vector-borne diseases including dengue fever, chikungunya, zika, yellow fever, leishmaniasis, chagas disease, and malaria, with highest incidences in tropical regions. In Ecuador, vector-borne diseases are present from coastal and Amazonian...

  4. Modulation of cytokine and cytokine receptor/antagonist by treatment with doxycycline and tetracycline in patients with dengue fever.

    Science.gov (United States)

    Castro, J E Z; Vado-Solis, I; Perez-Osorio, C; Fredeking, T M

    2011-01-01

    Dengue virus infection can lead to dengue fever (DF) or dengue hemorrhagic fever (DHF). Disease severity has been linked to an increase in various cytokine levels. In this study, we evaluated the effectiveness of doxycycline and tetracycline to modulate serum levels of IL-6, IL-1B, and TNF and cytokine receptor/receptor antagonist TNF-R1 and IL-1RA in patients with DF or DHF. Hospitalized patients were randomized to receive standard supportive care or supportive care combined with doxycycline or tetracycline therapy. Serum cytokine and cytokine receptor/antagonist levels were determined at the onset of therapy and after 3 and 7 days. Cytokine and cytokine receptor/antagonist levels were substantially elevated at day 0. IL-6, IL-1β, and TNF remained at or above day 0 levels throughout the study period in untreated patients. Treatment with tetracycline or doxycycline resulted in a significant decline in cytokine levels. Similarly, IL-1RA and TNF-R1 serum concentrations were elevated at baseline and showed a moderate increase among untreated patients. Both drugs resulted in a significant rise in IL-1Ra levels by day 3 in patients. In contrast, treatment did not affect a similar result for TNF-R1. When compared to the control group, however, a significant rise post-treatment was seen upon intragroup analysis. Further analysis demonstrated that doxycycline was significantly more effective at modulating cytokine and cytokine receptor/antagonist levels than tetracycline.

  5. Current perspectives on the spread of dengue in India

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    Gupta E

    2014-12-01

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

  6. Characterization of recombinant yellow fever-dengue vaccine viruses with human monoclonal antibodies targeting key conformational epitopes.

    Science.gov (United States)

    Lecouturier, Valerie; Berry, Catherine; Saulnier, Aure; Naville, Sophie; Manin, Catherine; Girerd-Chambaz, Yves; Crowe, James E; Jackson, Nicholas; Guy, Bruno

    2018-04-26

    The recombinant yellow fever-17D-dengue virus, live, attenuated, tetravalent dengue vaccine (CYD-TDV) is licensed in several dengue-endemic countries. Although the vaccine provides protection against dengue, the level of protection differs by serotype and warrants further investigation. We characterized the antigenic properties of each vaccine virus serotype using highly neutralizing human monoclonal antibodies (hmAbs) that bind quaternary structure-dependent epitopes. Specifically, we monitored the binding of dengue virus-1 (DENV-1; 1F4), DENV-2 (2D22) or DENV-3 (5J7) serotype-specific or DENV-1-4 cross-reactive (1C19) hmAbs to the four chimeric yellow fever-dengue vaccine viruses (CYD-1-4) included in phase III vaccine formulations using a range of biochemical and functional assays (dot blot, ELISA, surface plasmon resonance and plaque reduction neutralization assays). In addition, we used the "classic" live, attenuated DENV-2 vaccine serotype, immature CYD-2 viruses and DENV-2 virus-like particles as control antigens for anti-serotype-2 reactivity. The CYD vaccine serotypes were recognized by each hmAbs with the expected specificity, moreover, surface plasmon resonance indicated a high functional affinity interaction with the CYD serotypes. In addition, the hmAbs provided similar protection against CYD and wild-type dengue viruses in the in vitro neutralization assay. Overall, these findings demonstrate that the four CYD viruses used in clinical trials display key conformational and functional epitopes targeted by serotype-specific and/or cross-reactive neutralizing human antibodies. More specifically, we showed that CYD-2 displays serotype- specific epitopes present only on the mature virus. This indicates that the CYD-TDV has the ability to elicit antibody specificities which are similar to those induced by the wild type DENV. Future investigations will be needed to address the nature of CYD-TDV-induced responses after vaccine administration, and how these

  7. Dengue

    Science.gov (United States)

    ... emerged as a worldwide problem only since the 1950s. Although dengue rarely occurs in the continental United ... OIG 1600 Clifton Road Atlanta , GA 30329-4027 USA 800-CDC-INFO (800-232-4636) , TTY: 888- ...

  8. Landscape variation influences trophic cascades in dengue vector food webs.

    Science.gov (United States)

    Weterings, Robbie; Umponstira, Chanin; Buckley, Hannah L

    2018-02-01

    The epidemiology of vector-borne diseases is governed by a structured array of correlative and causative factors, including landscape (for example, rural versus urban), abiotic (for example, weather), and biotic (for example, food web) factors. Studies of mosquito-borne diseases rarely address these multiple factors at large spatial scales, which limits insights into how human alterations of landscapes and food webs alter mosquito abundance. We used structural equation modeling to identify the relative magnitude and direction of landscape, abiotic, and food web factors on Aedes larvae and adults across 70 sites in northern Thailand. Food web factors were modeled as mosquito-predator trophic cascades. Landscape context affected mosquito-predator communities in aquatic and terrestrial environments via cascading food web interactions. Several mosquito predators within these food webs showed potential as biocontrol agents in mosquito population control, but their potentials for control were landscape-dependent. In terrestrial food webs, the habitat-sensitive tokay gecko structured mosquito-predator communities, indicating that a conservation approach to vector control could be a useful addition to existing control efforts.

  9. 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.

  10. Social justice, climate change, and dengue.

    Science.gov (United States)

    Chang, Aileen Y; Fuller, Douglas O; Carrasquillo, Olveen; Beier, John C

    2014-06-14

    Climate change should be viewed fundamentally as an issue of global justice. Understanding the complex interplay of climatic and socioeconomic trends is imperative to protect human health and lessen the burden of diseases such as dengue fever. Dengue fever is rapidly expanding globally. Temperature, rainfall, and frequency of natural disasters, as well as non-climatic trends involving population growth and migration, urbanization, and international trade and travel, are expected to increase the prevalence of mosquito breeding sites, mosquito survival, the speed of mosquito reproduction, the speed of viral incubation, the distribution of dengue virus and its vectors, human migration patterns towards urban areas, and displacement after natural disasters. The burden of dengue disproportionately affects the poor due to increased environmental risk and decreased health care. Mobilization of social institutions is needed to improve the structural inequalities of poverty that predispose the poor to increased dengue fever infection and worse outcomes. This paper reviews the link between dengue and climatic factors as a starting point to developing a comprehensive understanding of how climate change affects dengue risk and how institutions can address the issues of social justice and dengue outbreaks that increasingly affect vulnerable urban populations. Copyright © 2014 Chang, Fuller, Carrasquillo, Beier. This is an open access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/), which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original author and source are credited.

  11. Dengue viruses – an overview

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    Anne Tuiskunen Bäck

    2013-08-01

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

  12. Extraction of mosquitocidals from Ocimum canum leaves for the control of dengue and malarial vectors

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    Pari Madhiyazhagan

    2014-09-01

    Full Text Available Objective: To assess the potentiality of Ocimum canum (O. canum (Lamiaceae in larvicidal, pupicidal, adulticidal, and repellent activities against the malarial vector, Anopheles stephensi (An. stephensi and the dengue vector, Aedes aegypti (Ae. aegypti. Methods: The mosquitocidal activity of methanol extracts from O. canum against immature and adult An. stephensi and Ae. aegypti (L. were studied. Standard WHO bioassays were used to evaluate the effectiveness of the plant extract against mosquitoes. Results: The methanol extract of O. canum was very effective against the immature stages of An. stephensi (LC50=193.280, 240.551, 303.409, 374.936 and pupa 469.547 mg/L and Ae. aegypti (LC 50=242.071, 287.277, 332.668, 394.061 and pupa 457.879 mg/L. Smoke toxicity assay showed significant mortality rate against adult An. stephensi (86.6% and Ae. aegypti (84.78%. The number of eggs laid by the females were strictly reduced after exposure to smoke. Conclusions: From the observed results we conclude that O. canum can be used as an effective larvicidal and repellent agent against the malarial and dengue vectors.

  13. Community-Effectiveness of Temephos for Dengue Vector Control: A Systematic Literature Review.

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    Leyanna George

    Full Text Available The application of the organophosphate larvicide temephos to water storage containers is one of the most commonly employed dengue vector control methods. This systematic literature review is to the knowledge of the authors the first that aims to assess the community-effectiveness of temephos in controlling both vectors and dengue transmission when delivered either as a single intervention or in combination with other interventions. A comprehensive literature search of 6 databases was performed (PubMed, WHOLIS, GIFT, CDSR, EMBASE, Wiley, grey literature and cross references were also screened for relevant studies. Data were extracted and methodological quality of the studies was assessed independently by two reviewers. 27 studies were included in this systematic review (11 single intervention studies and 16 combined intervention studies. All 11 single intervention studies showed consistently that using temephos led to a reduction in entomological indices. Although 11 of the 16 combined intervention studies showed that temephos application together with other chemical vector control methods also reduced entomological indices, this was either not sustained over time or-as in the five remaining studies--failed to reduce the immature stages. The community-effectiveness of temephos was found to be dependent on factors such as quality of delivery, water turnover rate, type of water, and environmental factors such as organic debris, temperature and exposure to sunlight. Timing of temephos deployment and its need for reapplication, along with behavioural factors such as the reluctance of its application to drinking water, and operational aspects such as cost, supplies, time and labour were further limitations identified in this review. In conclusion, when applied as a single intervention, temephos was found to be effective at suppressing entomological indices, however, the same effect has not been observed when temephos was applied in combination with

  14. Spatial Random Effects Survival Models to Assess Geographical Inequalities in Dengue Fever Using Bayesian Approach: a Case Study

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    Astuti Thamrin, Sri; Taufik, Irfan

    2018-03-01

    Dengue haemorrhagic fever (DHF) is an infectious disease caused by dengue virus. The increasing number of people with DHF disease correlates with the neighbourhood, for example sub-districts, and the characteristics of the sub-districts are formed from individuals who are domiciled in the sub-districts. Data containing individuals and sub-districts is a hierarchical data structure, called multilevel analysis. Frequently encountered response variable of the data is the time until an event occurs. Multilevel and spatial models are being increasingly used to obtain substantive information on area-level inequalities in DHF survival. Using a case study approach, we report on the implications of using multilevel with spatial survival models to study geographical inequalities in all cause survival.

  15. A Different Approach to Assess Oxidative Stress in Dengue Hemorrhagic Fever Patients Through The Calculation of Oxidative Stress Index

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    Edi Hartoyo

    2017-09-01

    Full Text Available The objectives of this study were to determine the involvement of Oxidative Stress (OS in the pathogenesis of dengue hemorrhagic fever (DHF through the analysis of oxidative stress Index (OSI. The levels of malondialdehyde (MDA, superoxide dismutase (SOD and catalase (CAT activity, and OSI were measured in 61 child dengue patients and (aged 6 months–18 years with three different stages of DHF, i.e stage I, II, and III. The results show that the levels of MDA, SOD and CAT activity, and OSI significantly different between the group. The all parameters that investigated in this present study seems higher MDA level and OSI in the higher grade of DHF, except for SOD and CAT activity. From this result, it can be concluded that oxidative stress pathways might be involved in the pathomechanism of DHF and OSI might be used as a biomarker for OS and the severity in DHF patients.

  16. Factors Associated with the Time of Admission among Notified Dengue Fever Cases in Region VIII Philippines from 2008 to 2014.

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    Jason Echavez Abello

    2016-10-01

    Full Text Available In cases of Dengue fever, late hospital admission can lead to treatment delay and even death. In order to improve early disease notification and management, it is essential to investigate the factors affecting the time of admission of Dengue cases. This study determined the factors associated with the time of admission among notified Dengue cases. The study covered the period between 2008 and 2014 in Region VIII, Philippines. The factors assessed were age, sex, hospital sector, hospital level, disease severity based on the 1997 WHO Dengue classification, and period of admission (distinguishing between the 2010 Dengue epidemic and non-epidemic time. We analysed secondary data from the surveillance of notified Dengue cases. We calculated the association through chi-square test, ordinal logistic regression and linear regression at p value < 0.05. The study included 16,357 admitted Dengue cases. The reported cases included a majority of children (70.09%, mild cases of the disease (64.00%, patients from the public sector (69.82%, and non-tertiary hospitals (62.76%. Only 1.40% of cases had a laboratory confirmation. The epidemic period in 2010 comprised 48.68% of all the admitted cases during this period. Late admission was more likely among adults than children (p<0.05. The severe type of the disease was more likely to be admitted late than the mild type (p<0.05. Late admission was also more likely in public hospitals than in private hospitals (p<0.05; and within tertiary level hospitals than non-tertiary hospitals (p<0.05. Late admission was more likely during the non-epidemic period than the 2010 epidemic period (p<0.05. A case fatality rate of 1 or greater was significantly associated with children, severe diseases, tertiary hospitals and public hospitals when admitted late (p<0.05. Data suggests that early admission among child cases was common in Region VIII. This behavior is encouraging, and should be continued. However, further study is needed

  17. Dengue vaccines: Challenges, development, current status and prospects

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    A Ghosh

    2015-01-01

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

  18. Cells in Dengue Virus Infection In Vivo

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    Sansanee Noisakran

    2010-01-01

    Full Text Available Dengue has been recognized as one of the most important vector-borne emerging infectious diseases globally. Though dengue normally causes a self-limiting infection, some patients may develop a life-threatening illness, dengue hemorrhagic fever (DHF/dengue shock syndrome (DSS. The reason why DHF/DSS occurs in certain individuals is unclear. Studies in the endemic regions suggest that the preexisting antibodies are a risk factor for DHF/DSS. Viremia and thrombocytopenia are the key clinical features of dengue virus infection in patients. The amounts of virus circulating in patients are highly correlated with severe dengue disease, DHF/DSS. Also, the disturbance, mainly a transient depression, of hematological cells is a critical clinical finding in acute dengue patients. However, the cells responsible for the dengue viremia are unresolved in spite of the intensive efforts been made. Dengue virus appears to replicate and proliferate in many adapted cell lines, but these in vitro properties are extremely difficult to be reproduced in primary cells or in vivo. This paper summarizes reports on the permissive cells in vitro and in vivo and suggests a hematological cell lineage for dengue virus infection in vivo, with the hope that a new focus will shed light on further understanding of the complexities of dengue disease.

  19. Yellow fever

    Science.gov (United States)

    ... to thrive. Blood tests can confirm the diagnosis. Treatment There is no specific treatment for yellow fever. ... SJ, Endy TP, Rothman AL, Barrett AD. Flaviviruses (dengue, yellow fever, Japanese encephalitis, West Nile encephalitis, St. ...

  20. [Knowledge of vector-borne diseases (dengue, rickettsiosis and Chagas disease) in physicians].

    Science.gov (United States)

    Lugo-Caballero, César I; Dzul-Rosado, Karla; Dzul-Tut, Irving; Balam-May, Ángel; Zavala-Castro, Jorge

    2017-01-01

    The ecological conditions of Yucatan made it a suitable region for the acquisition of vector-borne diseases such as dengue, rickettsiosis, and Chagas disease. As the epidemiological burden of these diseases shows an alarming increase of severe cases, the early establishment of diagnosis and therapeutics by first-contact physicians is a critical step that is not being fulfilled due to several reasons, including poor knowledge. To determine the level of knowledge related to dengue, Chagas disease, and rickettsiosis among rural first-contact physicians of Yucatan. A survey was applied to 90 first-contact physicians from rural clinics of Yucatan, which included 32 items related to the diagnosis, treatment, and prevention of dengue, rickettsiosis, and Chagas disease. Answers were analyzed by central tendency statistics. Differences were observed among every category, however; diagnosis and therapeutics showed the lower values. Globally, 62.5% of respondents showed moderate knowledge, 37.5% poor knowledge, and 0% adequate knowledge. Results suggest that a strong campaign for a continuous diffusion of knowledge regarding these diseases is needed. In regions with high prevalence of these kinds of diseases, like Yucatan, the impact of these results on the epidemiological burden of these diseases must be evaluated.

  1. Controlling dengue with vaccines in Thailand.

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    Dennis L Chao

    Full Text Available Dengue is a mosquito-borne infectious disease that constitutes a growing global threat with the habitat expansion of its vectors Aedes aegyti and A. albopictus and increasing urbanization. With no effective treatment and limited success of vector control, dengue vaccines constitute the best control measure for the foreseeable future. With four interacting dengue serotypes, the development of an effective vaccine has been a challenge. Several dengue vaccine candidates are currently being tested in clinical trials. Before the widespread introduction of a new dengue vaccine, one needs to consider how best to use limited supplies of vaccine given the complex dengue transmission dynamics and the immunological interaction among the four dengue serotypes.We developed an individual-level (including both humans and mosquitoes, stochastic simulation model for dengue transmission and control in a semi-rural area in Thailand. We calibrated the model to dengue serotype-specific infection, illness and hospitalization data from Thailand. Our simulations show that a realistic roll-out plan, starting with young children then covering progressively older individuals in following seasons, could reduce local transmission of dengue to low levels. Simulations indicate that this strategy could avert about 7,700 uncomplicated dengue fever cases and 220 dengue hospitalizations per 100,000 people at risk over a ten-year period.Vaccination will have an important role in controlling dengue. According to our modeling results, children should be prioritized to receive vaccine, but adults will also need to be vaccinated if one wants to reduce community-wide dengue transmission to low levels.

  2. Controlling Dengue with Vaccines in Thailand

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    Chao, Dennis L.; Halstead, Scott B.; Halloran, M. Elizabeth; Longini, Ira M.

    2012-01-01

    Background Dengue is a mosquito-borne infectious disease that constitutes a growing global threat with the habitat expansion of its vectors Aedes aegyti and A. albopictus and increasing urbanization. With no effective treatment and limited success of vector control, dengue vaccines constitute the best control measure for the foreseeable future. With four interacting dengue serotypes, the development of an effective vaccine has been a challenge. Several dengue vaccine candidates are currently being tested in clinical trials. Before the widespread introduction of a new dengue vaccine, one needs to consider how best to use limited supplies of vaccine given the complex dengue transmission dynamics and the immunological interaction among the four dengue serotypes. Methodology/Principal Findings We developed an individual-level (including both humans and mosquitoes), stochastic simulation model for dengue transmission and control in a semi-rural area in Thailand. We calibrated the model to dengue serotype-specific infection, illness and hospitalization data from Thailand. Our simulations show that a realistic roll-out plan, starting with young children then covering progressively older individuals in following seasons, could reduce local transmission of dengue to low levels. Simulations indicate that this strategy could avert about 7,700 uncomplicated dengue fever cases and 220 dengue hospitalizations per 100,000 people at risk over a ten-year period. Conclusions/Significance Vaccination will have an important role in controlling dengue. According to our modeling results, children should be prioritized to receive vaccine, but adults will also need to be vaccinated if one wants to reduce community-wide dengue transmission to low levels. PMID:23145197

  3. PLASMA LEAKAGE PROFILES OF DENGUE HEMORRHAGIC FEVER PATIENTS IN RSUD DR. SOETOMO, SURABAYA, EAST JAVA, INDONESIA JANUARY – JUNE 2014

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    Ferdian Rizaliansyah

    2017-04-01

    Full Text Available Plasma leakage is one crucial point of dengue hemorrhagic fever (DHF that differentiates it from dengue fever (DF. DHF has to meet 4 criteria which are 2 – 7 days of acute fever, hemorrhagic manifestation, thrombocytopenia (≤100.000 cells/mm3 and evidence of plasma leakage. Plasma leakage consists of increasing hematocrit ≥20%, hypoalbuminemia or evidence of pleural effusion or ascites. Often doctors only base their DHF diagnosis on the presence of thrombocytopenia. This study analyzed the presence of plasma leakage between adult and pediatric patients with a DHF diagnosis in RSUD Dr. Soetomo in order to make the diagnosis and healthcare services better in the future. This was a retrospective study which used medical records of DHF patients admitted from January to June 2014. 78 cases were included, 24 adult patients (31% and 54 pediatric patients (69%. 29/78 (37% patients had no evidence of plasma leakage. No adult patients had ascites whereas 11/54 (20% pediatric patients presented with ascites. No adult patients had pleural effusion whereas 25/54 (53% pediatric patients did. Most adult patients that had serum albumin checked had normal albumin levels (12/14 [86%] while only 14/28 (52% pediatric patients had normal albumin level. 5/22 (23% adult patients versus 32/53 (60% pediatric patients showed hematocrit increments ≥20%. Patients admitted with dengue virus infection may currently be often misclassified as DHF because there are no plasma leakage manifestation in some patients.. There are significant differences in plasma leakage manifestations between adult and pediatric patients which poses a theory that pediatric patients are more susceptible to have plasma leakage manifestations than adult patients.

  4. Prospective Cohort Study with Active Surveillance for Fever in Four Dengue Endemic Countries in Latin America

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    Dayan, Gustavo; Arredondo, Jose L.; Carrasquilla, Gabriel; Deseda, Carmen C.; Dietze, Reynaldo; Luz, Kleber; Costa, Maria Selma N.; Cunha, Rivaldo V.; Rey, Luis C.; Morales, Javier; Reynales, Humberto; Miranda, Maria; Zambrano, Betzana; Rivas, Enrique; Garbes, Pedro; Noriega, Fernando

    2015-01-01

    To prepare for a Phase III dengue vaccine efficacy trial, 20 investigational sites were selected for this observational study to identify dengue infections in a closed cohort (N = 3,000 children 9–16 years of age). Of 255 acute febrile episodes experienced by 235 children, 50 (21.3%) were considered serologically probable dengue, and 18 (7.7%) were considered virologically confirmed (i.e., dengue NS1 antigen positive) dengue cases. Considering the disease-free and at-risk period from study start to onset of symptoms, the overall incidence density of acute febrile episodes was 17.7 per 100 person-years of follow-up, ranging from 15.3 in Colombia to 22.0 in Puerto Rico. This study showed that all sites were capable of capturing and following up acute febrile episodes within a specific timeframe among the established cohort and to detect dengue cases. PMID:26013373

  5. Oropouche Fever: A Review

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    Hercules Sakkas

    2018-04-01

    Full Text Available Oropouche fever is an emerging zoonotic disease caused by Oropouche virus (OROV, an arthropod transmitted Orthobunyavirus circulating in South and Central America. During the last 60 years, more than 30 epidemics and over half a million clinical cases attributed to OROV infection have been reported in Brazil, Peru, Panama, Trinidad and Tobago. OROV fever is considered the second most frequent arboviral febrile disease in Brazil after dengue fever. OROV is transmitted through both urban and sylvatic transmission cycles, with the primary vector in the urban cycle being the anthropophilic biting midge Culicoides paraensis. Currently, there is no evidence of direct human-to-human OROV transmission. OROV fever is usually either undiagnosed due to its mild, self-limited manifestations or misdiagnosed because its clinical characteristics are similar to dengue, chikungunya, Zika and yellow fever, including malaria as well. At present, there is no specific antiviral treatment, and in the absence of a vaccine for effective prophylaxis of human populations in endemic areas, the disease prevention relies solely on vector control strategies and personal protection measures. OROV fever is considered to have the potential to spread across the American continent and under favorable climatic conditions may expand its geographic distribution to other continents. In view of OROV’s emergence, increased interest for formerly neglected tropical diseases and within the One Health concept, the existing knowledge and gaps of knowledge on OROV fever are reviewed.

  6. Oropouche Fever: A Review.

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    Sakkas, Hercules; Bozidis, Petros; Franks, Ashley; Papadopoulou, Chrissanthy

    2018-04-04

    Oropouche fever is an emerging zoonotic disease caused by Oropouche virus (OROV), an arthropod transmitted Orthobunyavirus circulating in South and Central America. During the last 60 years, more than 30 epidemics and over half a million clinical cases attributed to OROV infection have been reported in Brazil, Peru, Panama, Trinidad and Tobago. OROV fever is considered the second most frequent arboviral febrile disease in Brazil after dengue fever. OROV is transmitted through both urban and sylvatic transmission cycles, with the primary vector in the urban cycle being the anthropophilic biting midge Culicoides paraensis . Currently, there is no evidence of direct human-to-human OROV transmission. OROV fever is usually either undiagnosed due to its mild, self-limited manifestations or misdiagnosed because its clinical characteristics are similar to dengue, chikungunya, Zika and yellow fever, including malaria as well. At present, there is no specific antiviral treatment, and in the absence of a vaccine for effective prophylaxis of human populations in endemic areas, the disease prevention relies solely on vector control strategies and personal protection measures. OROV fever is considered to have the potential to spread across the American continent and under favorable climatic conditions may expand its geographic distribution to other continents. In view of OROV's emergence, increased interest for formerly neglected tropical diseases and within the One Health concept, the existing knowledge and gaps of knowledge on OROV fever are reviewed.

  7. Spatial-temporal analysis of dengue deaths: identifying social vulnerabilities

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    Maria do Socorro da Silva

    Full Text Available Abstract: INTRODUCTION Currently, dengue fever, chikungunya fever, and zika virus represent serious public health issues in Brazil, despite efforts to control the vector, the Aedes aegypti mosquito. METHODS: This was a descriptive and ecological study of dengue deaths occurring from 2002 to 2013 in São Luis, Maranhão, Brazil. Geoprocessing software was used to draw maps, linking the geo-referenced deaths with urban/social data at census tract level. RESULTS: There were 74 deaths, concentrated in areas of social vulnerability. CONCLUSIONS: The use of geo-technology tools pointed to a concentration of dengue deaths in specific intra-urban areas.

  8. Spatial-temporal analysis of dengue deaths: identifying social vulnerabilities.

    Science.gov (United States)

    Silva, Maria do Socorro da; Branco, Maria Dos Remédios Freitas Carvalho; Aquino, José; Queiroz, Rejane Christine de Sousa; Bani, Emanuele; Moreira, Emnielle Pinto Borges; Medeiros, Maria Nilza Lima; Rodrigues, Zulimar Márita Ribeiro

    2017-01-01

    Currently, dengue fever, chikungunya fever, and zika virus represent serious public health issues in Brazil, despite efforts to control the vector, the Aedes aegypti mosquito. This was a descriptive and ecological study of dengue deaths occurring from 2002 to 2013 in São Luis, Maranhão, Brazil. Geoprocessing software was used to draw maps, linking the geo-referenced deaths with urban/social data at census tract level. There were 74 deaths, concentrated in areas of social vulnerability. The use of geo-technology tools pointed to a concentration of dengue deaths in specific intra-urban areas.

  9. 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.

  10. Hot spot detection and spatio-temporal dispersion of dengue fever in Hanoi, Vietnam

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    Do Thi Thanh Toan

    2013-01-01

    Full Text Available Introduction: Dengue fever (DF in Vietnam remains a serious emerging arboviral disease, which generates significant concerns among international health authorities. Incidence rates of DF have increased significantly during the last few years in many provinces and cities, especially Hanoi. The purpose of this study was to detect DF hot spots and identify the disease dynamics dispersion of DF over the period between 2004 and 2009 in Hanoi, Vietnam. Methods: Daily data on DF cases and population data for each postcode area of Hanoi between January 1998 and December 2009 were obtained from the Hanoi Center for Preventive Health and the General Statistic Office of Vietnam. Moran's I statistic was used to assess the spatial autocorrelation of reported DF. Spatial scan statistics and logistic regression were used to identify space–time clusters and dispersion of DF. Results: The study revealed a clear trend of geographic expansion of DF transmission in Hanoi through the study periods (OR 1.17, 95% CI 1.02–1.34. The spatial scan statistics showed that 6/14 (42.9% districts in Hanoi had significant cluster patterns, which lasted 29 days and were limited to a radius of 1,000 m. The study also demonstrated that most DF cases occurred between June and November, during which the rainfall and temperatures are highest. Conclusions: There is evidence for the existence of statistically significant clusters of DF in Hanoi, and that the geographical distribution of DF has expanded over recent years. This finding provides a foundation for further investigation into the social and environmental factors responsible for changing disease patterns, and provides data to inform program planning for DF control.

  11. Hot spot detection and spatio-temporal dispersion of dengue fever in Hanoi, Vietnam.

    Science.gov (United States)

    Toan, Do Thi Thanh; Hu, Wenbiao; Quang Thai, Pham; Hoat, Luu Ngoc; Wright, Pamela; Martens, Pim

    2013-01-24

    Dengue fever (DF) in Vietnam remains a serious emerging arboviral disease, which generates significant concerns among international health authorities. Incidence rates of DF have increased significantly during the last few years in many provinces and cities, especially Hanoi. The purpose of this study was to detect DF hot spots and identify the disease dynamics dispersion of DF over the period between 2004 and 2009 in Hanoi, Vietnam. Daily data on DF cases and population data for each postcode area of Hanoi between January 1998 and December 2009 were obtained from the Hanoi Center for Preventive Health and the General Statistic Office of Vietnam. Moran's I statistic was used to assess the spatial autocorrelation of reported DF. Spatial scan statistics and logistic regression were used to identify space-time clusters and dispersion of DF. The study revealed a clear trend of geographic expansion of DF transmission in Hanoi through the study periods (OR 1.17, 95% CI 1.02-1.34). The spatial scan statistics showed that 6/14 (42.9%) districts in Hanoi had significant cluster patterns, which lasted 29 days and were limited to a radius of 1,000 m. The study also demonstrated that most DF cases occurred between June and November, during which the rainfall and temperatures are highest. There is evidence for the existence of statistically significant clusters of DF in Hanoi, and that the geographical distribution of DF has expanded over recent years. This finding provides a foundation for further investigation into the social and environmental factors responsible for changing disease patterns, and provides data to inform program planning for DF control.

  12. Seroprevalence of Infections with Dengue, Rift Valley Fever and Chikungunya Viruses in Kenya, 2007.

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    Caroline Ochieng

    Full Text Available Arthropod-borne viruses are a major constituent of emerging infectious diseases worldwide, but limited data are available on the prevalence, distribution, and risk factors for transmission in Kenya and East Africa. In this study, we used 1,091 HIV-negative blood specimens from the 2007 Kenya AIDS Indicator Survey (KAIS 2007 to test for the presence of IgG antibodies to dengue virus (DENV, chikungunya virus (CHIKV and Rift Valley fever virus (RVFV.The KAIS 2007 was a national population-based survey conducted by the Government of Kenya to provide comprehensive information needed to address the HIV/AIDS epidemic. Antibody testing for arboviruses was performed on stored blood specimens from KAIS 2007 through a two-step sandwich IgG ELISA using either commercially available kits or CDC-developed assays. Out of the 1,091 samples tested, 210 (19.2% were positive for IgG antibodies against at least one of the three arboviruses. DENV was the most common of the three viruses tested (12.5% positive, followed by RVFV and CHIKV (4.5% and 0.97%, respectively. For DENV and RVFV, the participant's province of residence was significantly associated (P≤.01 with seropositivity. Seroprevalence of DENV and RVFV increased with age, while there was no correlation between province of residence/age and seropositivity for CHIKV. Females had twelve times higher odds of exposure to CHIK as opposed to DENV and RVFV where both males and females had the same odds of exposure. Lack of education was significantly associated with a higher odds of previous infection with either DENV or RVFV (p <0.01. These data show that a number of people are at risk of arbovirus infections depending on their geographic location in Kenya and transmission of these pathogens is greater than previously appreciated. This poses a public health risk, especially for DENV.

  13. Spatial Patterns and Socioecological Drivers of Dengue Fever Transmission in Queensland, Australia

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    Clements, Archie; Williams, Gail; Tong, Shilu; Mengersen, Kerrie

    2011-01-01

    Background: Understanding how socioecological factors affect the transmission of dengue fever (DF) may help to develop an early warning system of DF. Objectives: We examined the impact of socioecological factors on the transmission of DF and assessed potential predictors of locally acquired and overseas-acquired cases of DF in Queensland, Australia. Methods: We obtained data from Queensland Health on the numbers of notified DF cases by local government area (LGA) in Queensland for the period 1 January 2002 through 31 December 2005. Data on weather and the socioeconomic index were obtained from the Australian Bureau of Meteorology and the Australian Bureau of Statistics, respectively. A Bayesian spatial conditional autoregressive model was fitted at the LGA level to quantify the relationship between DF and socioecological factors. Results: Our estimates suggest an increase in locally acquired DF of 6% [95% credible interval (CI): 2%, 11%] and 61% (95% CI: 2%, 241%) in association with a 1-mm increase in average monthly rainfall and a 1°C increase in average monthly maximum temperature between 2002 and 2005, respectively. By contrast, overseas-acquired DF cases increased by 1% (95% CI: 0%, 3%) and by 1% (95% CI: 0%, 2%) in association with a 1-mm increase in average monthly rainfall and a 1-unit increase in average socioeconomic index, respectively. Conclusions: Socioecological factors appear to influence the transmission of DF in Queensland, but the drivers of locally acquired and overseas-acquired DF may differ. DF risk is spatially clustered with different patterns for locally acquired and overseas-acquired cases. PMID:22015625

  14. Epidemiologi dan Diagnosis Dengue di Indonesia

    OpenAIRE

    Zilhadia, Zilhadia

    2007-01-01

    Dengue fever/DF and dengue hemorrhagic fever/DHF is a global public health problem that occured in tropical and subtropical region. Epidemic dengue occurs every years, and it continues to be a major health problem in Indonesia. Due to its asymptomatic nature, a reliable, rapid and accurate dengue diagnosis is needed. Dengue diagnosis method based on molecular dengue virus properties and it will be developed by researcher. Dengue rapid test isnewly method. This article explaine about dengue ep...

  15. Effect of the Topical Repellent para-Menthane-3,8-diol on Blood Feeding Behavior and Fecundity of the Dengue Virus Vector Aedes aegypti

    Directory of Open Access Journals (Sweden)

    Jugyeong Lee

    2018-06-01

    Full Text Available Dengue fever is an acute disease caused by the dengue virus and transmitted primarily by the mosquito Aedes aegypti. The current strategy for dengue prevention is vector control including the use of topical repellents to reduce mosquito biting. Although N,N-diethyl-m-methylbenzamide (DEET is the most common active ingredient in topical repellent products, para-menthane-3,8-diol (PMD is also used commercially. Studies have indicated PMD reduced biting by 90–95% for up to 6–8 h, similar to the efficacy of DEET, depending on the testing environment. The purpose of this study was to evaluate the behavioral effects of PMD on Ae. aegypti blood feeding and fecundity to explore the potential impact of PMD on downstream mosquito life-history traits. Two experiments were performed. In both experiments, cohorts of female Ae. aegypti (Belize strain were exposed to 20% PMD or ethanol for 10 min in a closed system and introduced to an artificial membrane feeding system. Following a 30min feed time, mosquitoes of Experiment 1 were killed and weighed as a proxy measure of blood meal, whereas mosquitoes of Experiment 2 were monitored for oviposition, a measure of fecundity. Results showed a statistically significant reduction (p < 0.001 in the percentage of Ae. aegypti that blood-fed when exposed to PMD (38% compared to those non-exposed (49%. No significant difference in fecundity between test populations was indicated. These findings suggest that exposure of Ae. aegypti to 20% PMD may influence the probability of subsequent blood feeding but of those mosquitoes that do blood feed, egg-lay density is not affected. Further studies are warranted to investigate the full range of effects of PMD exposure on other Ae. aegypti life-history traits such as mating, to continue characterizing the potential effects of PMD to impact overall vector population dynamics.

  16. Control of aedes vectors of dengue in three provinces of Vietnam by use of Mesocyclops (Copepoda) and community-based methods validated by entomologic, clinical, and serological surveillance.

    Science.gov (United States)

    Kay, Brian H; Nam, Vu Sinh; Tien, Tran Van; Yen, Nguyen Thi; Phong, Tran Vu; Diep, Vu Thi Bich; Ninh, Truong Uyen; Bektas, Ahmet; Aaskov, John G

    2002-01-01

    We describe remarkable success in controlling dengue vectors, Aedes aegypti (L.) and Aedes albopictus (Skuse), in 6 communes with 11,675 households and 49,647 people in the northern provinces of Haiphong, Hung Yen, and Nam Dinh in Vietnam. The communes were selected for high-frequency use of large outdoor concrete tanks and wells. These were found to be the source of 49.6-98.4% of Ae. aegypti larvae, which were amenable to treatment with local Mesocyclops, mainly M. woutersi Van der Velde, M. aspericornis (Daday) and M. thermocyclopoides Harada. Knowledge, attitude, and practice surveys were performed to determine whether the communities viewed dengue and dengue hemorrhagic fever as a serious health threat; to determine their knowledge of the etiology, attitudes, and practices regarding control methods including Mesocyclops; and to determine their receptivity t