The San Diego Blood Bank said Thursday that prospective blood donors recently returned from places with outbreaks of the Zika virus should refrain from giving blood for four weeks.
The waiting period was recommended Monday by the American Association of Blood Banks for people who have been to Mexico, South America or certain Pacific locales.
"We have notices up when people walk up to our counter," said Robert Baracz of the San Diego Blood Bank. He said that, as of late Thursday morning, no one had expressed any concern about the signs.
The illness has gained increasing notice in the past few weeks, after it was tentatively linked in Brazil to a condition called microcephaly in which babies with mothers sickened by Zika are born with small heads and have a shorter life expectancy.
The U.S. Centers for Disease Control and Prevention has issued a travel advisory for pregnant women planning to go to an affected country.
Health officials have said 80 percent of those who contract the Zika virus either don't get sick or have to deal with relatively minor symptoms. The disease is primarily spread by mosquitoes, but a sexually transmitted case recently occurred in Dallas.
The San Diego County Health and Human Services said last week that only two cases have been observed locally, one in July 2014, a traveler who returned from the Cook Islands, and the other last July in someone who visited Christmas Island. Both recovered after treatment. Zika outbreaks were occurring on both islands at the time.
Baracz said he hopes the blood bank's cautionary approach to the Zika virus won't discourage healthy people from donating.
"It shouldn't be a reason to scare anyone from coming in," Baracz said.
The national blood bank organization also recommended that people contact their donor center if they already gave blood soon after returning home from somewhere with a Zika outbreak. Baracz said packages of donated blood are labeled and can be tracked.
The association said its recommendations apply to two other tropical diseases — the chikungunya and dengue viruses.