Updated Reported Distribution of Aedes (Stegomyia) aegypti and Aedes (Stegomyia) albopictus (Diptera: Culicidae) in the United States, 1995-2016

Abstract

Aedes (Stegomyia) aegypti (L.) and Aedes (Stegomyia) albopictus (Skuse) are potential vectors of Zika, dengue, and chikungunya viruses in the United States. A Zika virus outbreak in Florida in the summer of 2016, driven by Ae. aegypti and resulting in > 200 locally acquired cases of human illness, underscored the need for up-to-date information on the geographic distribution of Ae. aegypti and Ae. albopictus in the United States. In early 2016, we conducted a survey and literature review to compile county records for presence of Ae. aegypti and Ae. albopictus in the United States from 1995 to 2016. Surveillance for these vectors was intensified across the United States during the summer and fall of 2016. At the end of 2016, we therefore conducted a follow-up survey of mosquito control agencies, university researchers, and state and local health departments to document new collection records for Ae. aegypti and Ae. albopictus. The repeated survey at the end of the year added Ae. aegypti collection records from 38 new counties and Ae. albopictus collection records from 127 new counties, representing a 21 and 10 percent increase, respectively, in the number of counties with reported presence of these mosquitoes compared with the previous report. Moreover, through our updated survey, 40 and 183 counties, respectively, added additional years of collection records for Ae. aegypti and Ae. albopictus from 1995 to 2016. Our findings underscore the continued need for systematic surveillance of Ae. aegypti and Ae. albopictus.

Keywords: Aedes aegypti; Aedes albopictus; United States; Zika virus; surveillance.

Fig. 1

Maps showing the reported occurrence of Ae. aegypti by county between 1 January 1995 and December 2016 in the United States, representing the best knowledge of the current distribution of this mosquito based on collection records. Counties with black dots had new surveillance records in this update. Counties shown in white had no reported Ae. aegypti presence records within the specified time period. Counties shown in yellow had Ae. aegypti presence records for one year within the specified time period, orange indicates those that had two years of presence records within the specified time period, and those shown in red had three or more years of presence records within the specified time period.

Fig. 2

Maps showing the reported occurrence of Ae. albopictus by county between 1 January 1995 and December 2016 in the United States, representing the best knowledge of the current distribution of this mosquito based on collection records. Counties with black dots had new surveillance records in this update. Counties shown in white had no reported Ae. albopictus presence records within the specified time period. Counties shown in yellow had Ae. albopictus presence records for one year within the specified time period, orange indicates those that had two years of presence records within the specified time period, and those shown in red had three or more years of presence records within the specified time period.