FDA Reviewing Blood Donation Policy During Zika Outbreak

— -- The U.S. Food and Drug Administration is reviewing policy around blood donation as the Zika virus continues to spread throughout the Western Hemisphere.

Dr. Anthony Fauci said in a press conference today that the FDA is already considering whether or not to change blood donation policies based on whether a person may have been exposed to the Zika virus.

"The FDA is looking at the issue of blood supply, blood donors and travelers," Fauci told reporters in a press conference today. "We know it’s in the blood stream very briefly, most people have cleared the bloodstream of the virus after about a week."

There are currently 31 confirmed cases of Zika virus in the U.S. and District of Columbia, although all were travelers who acquired the virus while abroad, according to the U.S. Centers for Disease Control. There are at least 20 cases in Puerto Rico and the U.S. Virgin Islands, where officials believe transmission is ongoing.

The virus often results in mild symptoms including fever, conjunctivitis and rash, but the new outbreak has been associated with a rise in the rare birth defect microcephaly.

More than 4,000 children in Brazil have been diagnosed with the condition, characterized by a small head and small brain. Officials are also investigating if a rare immunological syndrome called Guillain-Barre syndrome, is related. That syndrome can lead to temporarily paralysis of the muscles, and has been known to occur after viral or bacterial infections.

Fauci and Dr. Ann Schuchat, the CDC Deputy Director emphasized that a large-scale outbreak in the U.S. is unlikely due in part to urban areas that are less dense than those in South and Central Americas, mosquito controls, climate differences and other public health initiatives.

While the Zika virus is primarily spread through mosquito bites, there have been rare reports of other kinds of transmission including through sexual contact and blood donation.