Environmental health perspectives 2016 Oct 7()
Dengue fever, caused by a mosquito-transmitted virus, is an increasing health concern in the Americas. Meteorological variables such as temperature and precipitation can impact disease distribution and abundance through biophysical impacts on the vector and virus. Such tightly coupled links may facilitate further spread of dengue fever under a changing climate. In the southeastern United States, the dengue vector is widely established and exists on the current fringe of dengue transmission.
This paper assesses projected climate change-driven shifts in dengue transmission risk in this region.
We used a dynamic mosquito population and virus transmission model driven by meteorological data to simulate Aedes aegypti populations and dengue cases in 23 locations in the southeastern US under current climate conditions and future climate projections. We compared estimates for each location to simulations based on observed data from San Juan, Puerto Rico, where dengue is endemic.
Our simulations based on current climate data suggest that dengue transmission at levels similar to San Juan is possible at several US locations during the summer months, especially in southern Florida and Texas. Simulations that include climate change projections suggest that conditions may become suitable for virus transmission in a larger number of locations, and for a longer period of time during each year. However, in contrast with San Juan, US locations would not sustain year-round dengue transmission according to our model.
Our findings suggest that dengue virus transmission is limited by low winter temperatures in the mainland US, which are likely to prevent its permanent establishment. Although future climate conditions may increase the length of the mosquito season in many locations, projected increases in dengue transmission are limited to the southernmost locations.