The New York Times has reported that Florida announced on Thursday that, for the first time, mosquitoes in Miami Beach had tested positive for the Zika virus, a disappointing confirmation that the virus is still active in the area.
Florida is the only place in the continental United States where Zika is actively circulating, but the virus is spreading.
The Aedes aegypti mosquito that spreads Zika is famously difficult to fight, and experts often say that testing the bugs to find the virus is like looking for a needle in a haystack. The three samples that tested positive all came from a 1.5-square-mile area in Miami Beach where locally acquired cases of Zika had been confirmed.
The significance of the results depends on where the mosquitoes were collected, said Scott C. Weaver, the director of the Institute for Human Infections and Immunity at the University of Texas Medical Branch. If they are from in or around the houses of people with active infections, the chances of the bugs’ being infected are higher. If the virus was found in mosquitoes in a more distant location, that could point to a bigger infection area than thought.
A spokeswoman for the Florida Department of Agriculture and Consumer Services said state law prevented the disclosure of the traps’ location. The department said in a statement that since May, it had tested more than 2,470 mosquito samples, consisting of more than 40,000 mosquitoes. The three samples that the department announced on Thursday were the first to test positive.
