The complex relationship between weather and dengue virus transmission in Thailand.
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ABSTRACT:
SUBMITTER: Campbell KM
PROVIDER: S-EPMC3854883 | biostudies-literature | 2013 Dec
REPOSITORIES: biostudies-literature
Publications
The complex relationship between weather and dengue virus transmission in Thailand.
Campbell Karen M KM Lin C D CD Iamsirithaworn Sopon S Scott Thomas W TW
The American journal of tropical medicine and hygiene 20130819 6
Using a novel analytical approach, weather dynamics and seasonal dengue virus transmission cycles were profiled for each Thailand province, 1983-2001, using monthly assessments of cases, temperature, humidity, and rainfall. We observed systematic differences in the structure of seasonal transmission cycles of different magnitude, the role of weather in regulating seasonal cycles, necessary versus optimal transmission "weather-space," basis of large epidemics, and predictive indicators that estim ...[more]
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Project description:The epidemic of leptospirosis in humans occurs annually in Thailand. In this study, we have developed mathematical models to investigate transmission dynamics between humans, animals, and a contaminated environment. We compared different leptospire transmission models involving flooding and weather conditions, shedding and multiplication rate in a contaminated environment. We found that the model in which the transmission rate depends on both flooding and temperature, best-fits the reported human data on leptospirosis in Thailand. Our results indicate that flooding strongly contributes to disease transmission, where a high degree of flooding leads to a higher number of infected individuals. Sensitivity analysis showed that the transmission rate of leptospires from a contaminated environment was the most important parameter for the total number of human cases. Our results suggest that public education should target people who work in contaminated environments to prevent Leptospira infections.
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