March 13 (Reuters) - Local transmission of the Zika virus in Florida may have occurred as early as June 15 of last year and likely infected people who lived not only in Miami-Dade County, but in two nearby counties, U.S. health officials said on Monday.
The warning means that some men who donated semen to sperm banks in the area may not have been aware that they were at risk of infection, and may have donated sperm infected with the Zika virus, officials from the U.S. Centers for Disease Control and Prevention and the Food and Drug Administration told reporters in a telephone briefing.
The information is concerning because Zika has been shown to cause birth defects in women who become infected while pregnant. Previously, the CDC had warned of the risk of Zika in Miami-Dade County, beginning on July 29.
But the new warning dials that risk back to June 15, and adds in both Broward and Palm Beach Counties. (Reporting by Julie Steenhuysen in Chicago; Editing by Sandra Maler)