In this Jan. 18, 2016, photo, a female Aedes aegypti mosquito acquires a blood meal on the arm of a researcher at the Biomedical Sciences Institute in the Sao Paulo's University in Sao Paulo, Brazil. The CDC is working with Florida health officials to investigate what could be the first Zika infection from a mosquito bite in the continental United States.
In this Jan. 18, 2016, photo, a female Aedes aegypti mosquito acquires a blood meal on the arm of a researcher at the Biomedical Sciences Institute in the Sao Paulo's University in Sao Paulo, Brazil. The CDC is working with Florida health officials to investigate what could be the first Zika infection from a mosquito bite in the continental United States. Andre Penner AP
In this Jan. 18, 2016, photo, a female Aedes aegypti mosquito acquires a blood meal on the arm of a researcher at the Biomedical Sciences Institute in the Sao Paulo's University in Sao Paulo, Brazil. The CDC is working with Florida health officials to investigate what could be the first Zika infection from a mosquito bite in the continental United States. Andre Penner AP

How a Caribbean island became prime source of U.S. Zika cases

July 22, 2016 7:00 AM