The CDC will shift the time-frame, and its area of potential increased risk, for blood and tissue sample guidance for Zika transmission for residents of South Florida, according to the agency.
In a call with media, CDC and FDA researchers explained that, based on both recent cases and new information from older cases reported into the Zika surveillance system, the date for increased risk for Zika transmission has been moved to June 15. In addition, the areas of increased risk has been expanded from Miami-Dade County to include both Palm Beach and Broward Counties.
Denise Jamieson, MD, of the CDC in Atlanta, explained that the surveillance system has identified residents in Palm Beach and Broward counties where exposure to Zika was "uncertain." The residents may have traveled to Miami-Dade, but did not remember doing so "due to daily activities through the tri-county area," she said.
Of particular concern is Zika's persistence in reproductive tissue, particularly semen. Researchers highlighted the potential risk to women who have become pregnant since June 15 whose partners live in the tri-county area of South Florida, as well as women who have used donor semen from residents of the tri-county area to become pregnant since that date.
These patients are encouraged to have a conversation with their healthcare providers, as they are now considered to be at increased risk for Zika transmission.
"The concern is when semen is donated, it can be stored or frozen for significant periods of time, and it does not inactivate anything with Zika virus," said Peter Marks, MD, of the FDA. "One could have stored semen samples in various tissue banks that could be used subsequently, and this guidance allows people to consider whether they want to use those."
There is currently no test on the market that can be used to identify Zika virus in semen.
No changes have been made to the FDA guidance on blood and tissue products. CDC researchers added that there has been no new evidence of local transmission in other Florida counties.