Last year, with the Western Hemisphere in the grip of a surprising Zika virus epidemic, CDC researchers used a survey to compile a list of U.S. counties where the mosquito at the heart of the epidemic, Aedes aegypti, had been documented over the past 21 years. They also documented counties that reported finding another mosquito, A. albopictus, known to transmit chikungunya and dengue viruses. The researchers said their data could be used to guide surveillance and mosquito control efforts across the country.
