The American Red Cross appealed on Tuesday to prospective blood donors who have traveled to Zika virus outbreak areas to wait at least 28 days before donating their blood.
The "self-deferral" for blood donors should apply to those who have visited Mexico, the Caribbean, or Central or South America during the past four weeks, the Red Cross said in a statement.
The Zika outbreak, a mosquito-born illness linked to a dangerous birth defect called microcephaly, now affects more than 30 countries and territories.
(Reporting by Sara Catania in Los Angeles. Writing and additional reporting by Steve Gorman in Los Angeles; Editing by Richard Chang)