The Department of Health and Human Services is arranging and funding shipments of blood products from the continental United States to Puerto Rico, the first of which arrived Saturday, to ensure an adequate supply of safe blood as the island experiences active Zika virus transmission. The American Red Cross, Blood Centers of America, and America’s Blood Centers are providing the shipments to existing blood collection centers, which will supply them to transfusion providers. Local mosquito-borne transmission of Zika has been reported in the U.S. territories of Puerto Rico, American Samoa and the U.S. Virgin Islands, with most of the cases in Puerto Rico. HHS is working with manufacturers to develop blood donor screening tests and additional pathogen reduction technologies to help protect the U.S. blood supply and blood components in areas with active transmission. Recent evidence suggests a possible association between maternal Zika virus infection and adverse fetal outcomes, such as microcephaly. Until more is known, the Centers for Disease Control and Prevention strongly advises pregnant women to consider postponing travel to Zika-affected areas. For more information, visit and