MIAMI BEACH, Fla. — Aerial spraying of the insecticide naled is scheduled over South Beach, where more mosquitoes have tested positive for the Zika virus.

In a statement Tuesday, Miami-Dade County Mayor Carlos Gimenez said the flights recommended by Florida health officials and the U.S. Centers for Disease Control and Prevention will begin Thursday and continue for a month.

Gimenez said the number of Miami Beach mosquitoes found with Zika increased over the weekend. The insects were trapped in a 1.5-square-mile infection zone.

The aerial spraying targets adult mosquitoes. Different pesticides for larvae will be sprayed on the ground.

Citing residents’ concerns about naled, Miami Beach’s mayor has said he didn’t favor aerial spraying, and a city commissioner drafted an ordinance opposing its use.

Of Florida’s 56 non-travel related Zika cases, 11 are associated with Miami Beach.