Aedes aegypti in Maryland: The need for elevated vector surveillance at the face of a dynamic climate

We report the collection of three Aedes aegypti adult female mosquitoes in a Rockville, Maryland backyard in late July, 2023, followed by the emergence of 15 adults collected as larvae in a residential backyard in Baltimore, Maryland in mid-September, 2023. Aedes aegypti is a species primarily associated with tropical and subtropical regions, known for its significance as a vector of arboviruses, including Yellow Fever, Dengue, Zika, and Chikungunya among others. In the continental United States, Ae. aegypti populations are mostly found in the southeast, and in several isolated locations such as southern California and Arizona. This finding raises questions about the potential establishment and survival of Ae. aegypti in temperate climates, emphasizing the critical importance of robust vector surveillance programs in preventing potential outbreaks of vector-borne diseases in regions not traditionally considered endemic for this species.