FDA: All donated blood in U.S. should be tested for Zika

The Food and Drug Administration on Friday took steps to safeguard the nation’s blood supply from the Zika virus, calling for all blood banks to screen donations for the infection even in states where the virus is not circulating.

The recommendations are an acknowledgment that sexual transmission may facilitate the spread of Zika even in areas where mosquitoes carrying the virus are not present. Officials also want to prepare for the possibility that clusters of local infection will continue to pop up in parts of the United States for years to come.

“There could be multiple outbreaks of Zika happening outside the known current ones in South Florida, but because we are not actively looking they could be happening silently,” said Dr. Peter J. Hotez, the dean of the National School of Tropical Medicine at Baylor College of Medicine, who applauded the F.D.A.’s move.