The federal government is shipping blood and blood products to Puerto Rico because of worries that local supplies might be contaminated with mosquito-borne Zika virus.
The Health and Human Services Department said it was organizing shipments of blood products from the continental United States to Puerto Rico, where Zika is spreading fast.
Last month, Centers for Disease Control and Prevention Director Dr. Thomas Frieden said Puerto Rico can expect to be hit especially hard with Zika, because it's got Aedes aegypti mosquitoes, which carry and spread the virus.
"We will likely see significant numbers of cases in Puerto Rico and other U.S. territories," Frieden told a House Foreign Affairs subcommittee hearing on Zika.
The Food and Drug Administration has asked people living in or traveling from Zika-affected zones to delay giving blood until they are in the clear.
"In the absence of special measures to screen for infection or reduce pathogens, the risk of Zika virus transmission through blood products is considered likely based on the most current scientific evidence of how Zika virus and similar viruses (flaviviruses) are spread, and what is currently being reported about transfusion-associated infection occurring outside of the United States," HHS said in a statement.
"We are arranging the importation of blood products from areas unaffected by local Zika transmission to ensure the safety of Puerto Rico's blood supply," said
"Availability of safe blood products for the residents of Puerto Rico is a major priority for HHS," said Dr. Karen DeSalvo, the agency's acting assistant secretary for health.
This story originally appeared on NBCNews.com.