U.S. Faces a Rise in Mosquito ‘Disease Danger Days’


Research Report by Climate Central

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Among the many consequences of human-caused climate change is a change in the pattern, incidence and location of some diseases spread by biting mosquitoes, ticks and flies. These diseases pose a significant public health challenge globally, including in the United States.

The number of mosquito “disease danger days” is increasing across much of the U.S. as temperatures rise, representing a greater risk for transmission of mosquito-borne diseases. And even though mosquitoes are often just an itch-inducing nuisance, the consequences can be deadly.

Mosquitoes are major carriers of these diseases, with a variety found throughout the U.S. While Culex mosquitoes are found across the United States, two species, Aedes aegypti and Aedes albopictus, which carry some dangerous diseases and thus are the subjects of many studies, have a more limited range in the U.S. These two species tend to be found in the South and Southeast, though the former’s range extends into California and the latter’s range extends northeast towards New York and New England and has the potential to exist in the Midwest. Although other species of Aedes mosquitoes exist, in the remainder of this