From The New York Times:
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 was still active in the area.
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 previously thought.