Dengue virus surveillance for early warning, Singapore.
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ABSTRACT:
SUBMITTER: Lee KS
PROVIDER: S-EPMC2953985 | biostudies-literature | 2010 May
REPOSITORIES: biostudies-literature
Publications
Dengue virus surveillance for early warning, Singapore.
Lee Kim Sung KS Lai Yee Ling YL Lo Sharon S Barkham Timothy T Aw Pauline P Ooi Peng Lim PL Tai Ji Choong JC Hibberd Martin M Johansson Patrik P Khoo Seow Poh SP Ng Lee Ching LC
Emerging infectious diseases 20100501 5
In Singapore, after a major outbreak of dengue in 2005, another outbreak occurred in 2007. Laboratory-based surveillance detected a switch from dengue virus serotype 1 (DENV-1) to DENV-2. Phylogenetic analysis showed a clade replacement within DENV-2 cosmopolitan genotype, which accompanied the predominant serotype switch, and cocirculation of multiple genotypes of DENV-3. ...[more]
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Project description:Singapore experienced its first documented Zika virus outbreak in 2016. We identified clinical and laboratory parameters that increase the probability for Zika or dengue virus infection. Early during the illness, combinations of key parameters obtained through clinical assessment and hematologic tests can help distinguish between these infections.
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Project description:Arbovirus epidemiology lacks efficient and timely surveillance systems with accurate outbreak alert signals. We devised a citywide integrated surveillance system combining entomologic, epidemiologic, and entomo-virologic data gathered during 2017-2020 in Foz do Iguaçu, Brazil. We installed 3,476 adult mosquito traps across the city and inspected traps every 2 months. We compared 5 entomologic indices: traditional house and Breteau indices for larval surveys and trap positivity, adult density, and mosquitoes per inhabitant indices for adult trapping. We screened for dengue, Zika, and chikungunya viruses in live adult Aedes aegypti mosquitoes collected from traps. Indices based on adult mosquito sampling had higher outbreak predictive values than larval indices, and we were able to build choropleth maps of infestation levels <36 h after each round of trap inspection. Locating naturally infected vectors provides a timely support tool for local public health managers to prioritize areas for intervention response to prevent virus outbreaks.
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