blood stock photo

The Food and Drug Administration has ordered a halt to donations at all blood collection centers in Florida’s Miami-Dade and Broward counties after four new cases of Zika virus transmission are suspected to have occurred there.

While the cases are under investigation, the FDA issued an urgent memorandum restricting blood donations until proper testing or pathogen killing procedures for Zika can be established.  

According to the Centers for Disease Control and Prevention, the measures come after two Zika cases were identified in Broward and Miami-Dade Counties and were determined to not be related to travel within infectious areas.  

“All the evidence we have seen indicates that this is mosquito-borne transmission that occurred several weeks ago in several blocks in Miami,” said Dr. Tom Frieden, director of the CDC. “We continue to recommend that everyone in areas where Aedes aegypti mosquitoes are present—and especially pregnant women—take steps to avoid mosquito bites. We will continue to support Florida’s efforts to investigate and respond to Zika and will reassess the situation and our recommendations on a daily basis.”

Additionally, the FDA warning recommended that adjacent and nearby counties implement similar precautions as those mandated for Broward and Miami-Dade Counties “to help maintain the safety of the blood supply as soon as possible.”  For blood collection establishments outside of the immediate region, the FDA suggests that donors who have traveled to Miami-Dade and Broward Counties during the previous four weeks be deferred from donating until they are certain they have not been exposed.

As of July 27, the CDC has identified 1,658 cases of Zika in the continental United States and Hawaii, none of which have been linked to bite from local mosquitoes. However, 15 U.S. cases have been linked to sexual transmission, and one to laboratory exposure.  This number does not include the four new Florida cases likely caused by local transmission.

Although Zika is primarily spread by the bite of an infected mosquito, it can also be spread through blood transfusions and sex with an infected person. The CDC is also investigating a case in Utah in which a caregiver may have contracted the virus from an elderly person with high levels of the Zika virus in his blood who later died.

“We have been working with state and local governments to prepare for the likelihood of local mosquito-borne Zika virus transmission in the continental United States and Hawaii,” Dr. Lyle Petersen, incident manager for CDC’s Zika virus response, said in a statement. “We anticipate that there may be additional cases of ‘homegrown’ Zika in the coming weeks.  Our top priority is to protect pregnant women from the potentially devastating harm caused by Zika.”

The FDA said it will continue to monitor the situation in Florida in cooperation with the CDC and state public health authorities, and provide updates as additional information becomes available.