A shortage of supply in blood banks may be on the horizon, as donors who have traveled to areas that are high-risk for the Zika virus are likely driven away.

Blood supply shortages are more pronounced in the winter time due to holiday travel and the flu. The threat of the Zika virus, which affects over 25 countries and territories, may put even more strain on the supply.

Last week, the American Red Cross announced a 28-day waiting period before donating for travelers who went to at-risk places such as Mexico, the Caribbean, and Central and South America.

In that week alone, senior blood consultant Tammy Winchester of Heartland Blood Centers in Chicago turned away around 20 potential donors who recently traveled to such at-risk areas.

“There’s always a blood shortage is what I say. Right now we are in need O-neg and A-neg,” Winchester shared in an interview.

Nonprofit United Blood Services has made the same request to donors to hold off donating blood for 28 days after leaving at-risk areas. In a statement, it stressed that Zika virus could be transmitted via blood transfusion, and there is currently no test to screen blood donors.

“We are aware that the U.S. Food and Drug Administration is discussing official guidance about donors who have traveled to these regions. Until that guidance is available, we are taking this cautionary step,” said Dr. Hany Kamel, VP and corporate medical director for Blood Systems, United Blood Services’ national office.

Latest survey of community blood centers estimated a 2 percent reduction in eligible donors in the U.S. following the restriction.

However, since this development in blood donation hits in the middle of the cold and flu season, those who are healthy and not affected by the imposed post-travel waiting period are urged to keep donating blood in the coming weeks.

The World Health Organization has declared the Zika virus outbreak an international emergency, finding a link between the infection during pregnancy and growing cases of a birth defect known as microcephaly.

Zika – first discovered in the Zika forest of Uganda back in 1947 – is particularly sinister because most patients do not exhibit any symptom, and those who do may show no more than the flu or a bad case of the cold.

The WHO has only classified three other epidemics as a global emergency, namely the 2009 swine flu epidemic, the resurfacing of polio in Syria and Pakistan in 2014, and the wild spread of Ebola in West African nations in the same year.

Photo: Matthew Allen Hecht | Flickr