CDC expands time frame for Zika risk

The CDC has updated its Zika testing guidelines for South Florida to recommend blood and tissue sampling for concerned residents, pregnant women or tourists who were in the region after June 15, 2016.

The date for increased risk of exposure was pushed back from Aug. 16, 2016 based on data from previous cases reported to the Zika surveillance system.

Women who have become pregnant since June 15, whose partners or sperm donors live in the South Florida area are encouraged to visit their health care providers to discuss risk of fetal transmission.

The agency highlights previous research showing that the virus may persist in reproductive tissue, particularly semen. A recent case demonstrated presence of Zika RNA in the semen of a tourist 92 days after symptom onset. Those interested in utilizing donor semen in the future should also take the risk period into account.

"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, PhD, director of the center for Biologics Evaluation and Research at 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."