Zika can be transmitted several ways, through mosquito bites, sex and blood transfusions. The virus lasts in the bloodstream for a week or two. Although the risk of acquiring Zika through blood products is considered fairly low in the U.S. right now, blood banks are facing a tough transition when dealing with this emerging health threat.
Anyone who has ever rolled up his sleeves to donate blood knows the drill. You answer a slew of health questions and sign consent for your blood to be tested for everything from HIV to Hepatitis C. Now the South Texas Blood and Tissue Center in San Antonio is asking donors to consent to a Zika test. The Center was the second in the country behind Houston to implement this experimental screening to, even before the Florida outbreak.
"We just want to make sure that it’s not in the blood supply," said Elizabeth Waltman, Chief Operating Officer for the blood bank in San Antonio. "We wanted to make sure that we weren’t waiting for the most horrific thing to happen before we started testing. It wasn’t something that we wanted to play around with."
Zika blood test is experimental
The Zika test is considered specific and sensitive by blood banks using it. It’s still experimental, though, because it hasn’t been approved by the Food and Drug Administration.
In the last six weeks, the South Texas center has screened 20,000 donations. "So far we’ve not located Zika in the blood supply so that’s good news for our community," Waltman stated.
20 percent of donors opting out
However, one in five donors is opting out of the test, declining to allow their blood to be screened for Zika. Those who refuse seem skeptical.
"When people come up against something that they’re unfamiliar with, they’re a bit hesitant," commented Dr. Rachel Beddard who is the Medical Director for Biobridge Global, the parent company that oversees the blood center. "You always expect some refusals. There’s always some people that just are not willing to do anything that’s different. But I really want people to carefully consider it."
The process does not involve an extra needle stick. A sample of the donation is simply sent off to a lab in Atlanta. Donor Robert Sackett of Helotes calls it “no big deal.”
"They’re already sticking you for blood anyway for the donation, so they just draw another tube from you," explained Sackett.
San Antonian Ronny Rodriguez says he would want to know if he had Zika. "We have mosquitoes all the time. And I always actually get bit by mosquitoes so it would be news to me to find out if I’ve gotten attacked by a mosquito carrying the Zika virus," Rodriguez said.
Zika testing protocol
A donor who tests positive will get a call and a letter and the case is reported to the health department. That person’s donated blood will be discarded. If South Texas does become an outbreak area, all blood would be tested for Zika and anyone who refused the screening would not be allowed to donate.
80 percent of people who are infected with Zika have no symptoms. They feel well. That’s why the blood donation process may pick up the first cases in an area, kind of like the “canary in the coal mine” according to Beddard.
"We are expecting that this will happen in our area," Beddard stressed. "It’s just a matter of time."
Zika-tested blood is kept separate from non-tested blood. Hospitals can order the screened donations for their high risk patients like pregnant women and women of child-bearing age, since Zika’s main threat is devastating birth defects. Pregnant women or women trying to conceive who need a blood product for a medical procedure can ask their doctors if the donations have been screened for Zika.
In the Florida outbreak counties, blood donations were first suspended, then resumed when Zika testing became the standard. While the Zika blood test is on the FDA fast track to approval, it may be a year or two before that happens. Even then, it’s unclear if it will be used universally.
The only other blood bank in San Antonio is at University Hospital. Blood is drawn from employees, community, family and patients to support the busy level one trauma center. University does not test for Zika. Right now, when they need Zika-tested blood, they order it from the South Texas Blood and Tissue Center.