Modeling changes in Aedes aegypti habitat
Rapid changes in the distributions of the mosquito species Aedes aegypti in the continental United States alter the potential for local transmission of dengue, chikungunya, and Zika viruses. The expanding range of these mosquitoes and discovery of new populations within the U.S. raises questions about whether recent spread has been enabled by climate change or other anthropogenic influences. In our analysis, we use daily average temperatures for the United States to model Ae. aegypti population growth rates using a stage-structured matrix population model to understand the past and present habitat suitability of this vector, and to project future habitat suitability under IPCC climate change scenario representative concentration pathway (RCP) 4.5. Our results indicate that much of the southern U.S. is suitable for Ae. aegypti year-round; however, a surprisingly large proportion of the U.S. in addition to southern states is suitable for positive population growth for much of the year. Additionally, IPCC CMIP5 model projections of future climate change suggest that climate change will expand the range and increase population growth rates of Ae. aegypti in the U.S., potentially increasing the range of the viruses they transmit. We also used this model to build a web-based application available here to estimate seasonal population dynamics of Ae. aegypti and Ae. albopictus populations in California.