MIAMI (AP) -- Mosquitoes have apparently begun spreading the Zika virus on the U.S. mainland for the first time, health officials said Friday, a long-feared turn in the epidemic that is sweeping Latin America and the Caribbean.
Four recently infected people in the Miami area -- one woman and three men -- are believed to have contracted the virus locally through mosquito bites, Gov. Rick Scott said.
No mosquitoes in Florida have actually been found to be carrying Zika, despite the testing of 19,000 by the state lab. But other methods of Zika transmission, such as travel to a stricken country or sex with an infected person, have been ruled out.
"Zika is now here," said Dr. Thomas Frieden, director of the U.S. Centers for Disease Control and Prevention.

FDA temporarily halts blood donation in two Florida counties over Zika fears 

The U.S. Food and Drug Administration is asking blood centers in two Florida counties to immediately stop collections. The counties are investigating possible local transmission of Zika virus.
In a notice sent to blood centers and posted on the agency's website Wednesday evening, the FDA said it is requesting all blood centers in Miami-Dade or Broward counties to "cease collecting blood immediately" until those facilities can test individual units of blood donated in those two counties with a special investigational donor screening test for Zika virus or until the establishments implement the use of an approved or investigational pathogen-inactivation technology.
The action by the FDA comes as health officials in Florida said Thursday they were continuing to investigate two Zika cases that could have been spread by local mosquitoes, in addition to two similar cases they announced last week. Health officials have not confirmed whether any of the infected individuals acquired the virus from local mosquitoes, but it seems increasingly likely.