Federal Agencies Prepare to Battle Zika Virus in the U.S.

As spring arrives and the threat of Zika virus grows in the U.S., the Centers for Disease Control and Prevention (CDC) and the U.S. Food and Drug Administration (FDA) are taking action to address the virus threat.

April 1, 2016, the Centers for Disease Control and Prevention (CDC) hosted 300 federal, state and local government representatives, health care professionals and private stakeholders at a national summit to discuss how to prepare to battle the Zika virus here in the U.S. “The mosquitoes that carry Zika virus are already active in U.S. territories, hundreds of travelers with Zika have already returned to the continental U.S., and we could well see clusters of Zika virus in the continental U.S. in the coming months. Urgent action is needed, especially to minimize the risk of exposure during pregnancy,” said CDC Director Tom Frieden, M.D., M.P.H. in the CDC’s release announcing the summit. The CDC also released a report that includes maps of the U.S. indicating the agency’s estimate of where the mosquitoes that carry Zika virus can be found.

Amy Pope, J.D., White House Deputy Homeland Security Advisor and Deputy Assistant to the President also noted in the CDC statement the President’s $1.9 million funding request to “prepare for, detect, and respond to any potential Zika outbreaks” in the U.S.

The FDA has also issued several guidances and approved some tests for detecting the virus, while questioning the developers of other tests.

FDA Guidance and Testing Approved for Donated Blood
Days before the summit, the FDA announced that a screening test to detect Zika virus in blood donations was available for use under an investigational new drug application. Noting the importance of protecting the nation’s blood supply and screening blood in U.S. territories already affected by Zika transmissions, Peter Marks, M.D., Ph.D., director of the FDA’s Center for Biologics Evaluation and Research, said in a statement: “In the future, should Zika virus transmission occur in other areas, blood collection establishments will be able to continue to collect blood and use the investigational screening test, minimizing disruption to the blood supply.”

Roche, whose cobas® Zika test was authorized for use to screen blood donations, says the “first stage” will be to use the test in Puerto Rico to reduce the need to import blood and the “second stage of deployment” for the test will be use “in the southern United States, which will most likely be impacted by any spread in the virus.” “All Testing Laboratories will need to be enrolled in and contracted into the clinical trial as specified and agreed with the FDA Center for Biologics Evaluation and Research.”.

Previously, in February 2016, the FDA issued recommendations on how to reduce risk of transmission via blood transfusion. Blood establishments, in areas with active Zika virus transmission, need to obtain whole blood and blood components for transfusion from areas of the U.S. without active transmission. Collection and preparation of platelets and plasmas can continue as long as FDA-approved pathogen-reduction device is used. For those blood facilities in areas without Zika virus transmission, FDA noted importance of deferral of donors at risk of Zika virus for four weeks.

FDA Urges Caution in Donations of Human Cells and Tissues
FDA is intent on reducing risk of transmitting the Zika virus from human cell, tissues and cellular and tissue-based products (HCT/Ps). The agency released March 1 recommendations for handling these donations from living and deceased donors.

The FDA said people should be considered ineligible of donating HCT/Ps if they were: 1) diagnosed with the Zika virus infection; 2) were in an area with active Zika virus transmission; or 3) had sex with a male with either of those risk factors within the past six months. As to donations of HCT/Ps from deceased, the FDA advises they not be accepted when the donor had the Zika virus within six months of death.

The FDA points out in its guidance document that HCT/Ps with the highest potential for transmission of the Zika virus are those recovered from living donors.

FDA Takes Action Concerning New Zika Tests
The FDA granted approval for a diagnostic test for the Zika virus to be distributed to certified labs by the CDC. The test is the CDC Zika IgM Antibody Capture Enzyme-Linked Immunosorbent Assay (Zika MAC-ELISA).The CDC, which made an emergency use request for the test, is sharing it with labs in the Laboratory Response Network, a group of domestic and international labs that respond to public health emergencies. Hospitals and other providers seeking the tests for patients need to work through the CDC and CDC-certified labs.

But while this test got the green light by the FDA, the agency wrote other test-makers to challenge their Zika tests, seeking agency review of their design, validation and performance. MD Biosciences Clinical and Diagnostic Services Laboratory announced in March a rapid assay to detect the Zika virus in human blood and urine samples. The FDA issued a letter to MD Biosciences, Inc. indicating the test “appears to meet the definition of a device” under section 201(h) of the Federal Food, Drug, and Cosmetic Act and should be subject to premarket clearance, approval or Emergency Use Authorization. The letter added that “it is particularly important for the FDA to review information related to your Zika Virus RNA by RT-PCR Assay’s design, validation and performance characteristics.”

The company, after receiving a letter from the FDA, said it is “proceeding with the Zika test services following clarification with the FDA regarding any pre-market approval requirements pertaining to this assay. Testing services will not be offered pending this clarification.”

The FDA has issued similar letters regarding other tests: to First Diagnostic Corporation for its ATFirst’s One Step Zika Antibody Test and to Texas Children’s Hospital and Houston Methodist Hospital for their Zika Direct Test intended as a rapid diagnostic test. The FDA also states in those letters the need for the agency to review the “design, validation, and performance characteristics of those tests.”