The FDA has issued new guidelines for reducing the possible transmission risk of Zika virus from human cells, tissues, and cellular and tissue-based products (HCT/Ps) from both living and deceased donors, including donors of umbilical cord blood, placenta, or other gestational tissues.
There is a potential risk that the Zika virus can be transmitted by HCT/Ps used as part of a medical, surgical, or reproductive procedure. HCT/Ps include products such as corneas, bone, skin, heart valves, hematopoietic stem/progenitor cells (HPCs), gestational tissues such as amniotic membrane, and reproductive tissues such as semen and oocytes.
“Though there is more to be learned about the transmission of Zika virus, given what we know about the virus at this point, which also is informed by our understanding of similar viruses, we must address the potential risk of Zika virus transmission by human cells and tissues,” stated Dr Peter Marks, M.D., Ph.D., director of the FDA’s Center for Biologics Evaluation and Research. “Providing HCT/P establishments with donor eligibility recommendations will help reduce that potential risk.”
According to the CDC, there have already been a number of cases in which the Zika has been spread by men to their sexual partners. In addition, the detection in semen suggests that a period of ineligibility longer than the waiting period that has been recommended for donors of whole blood and blood components is necessary for HCT/P donors. As a result the Food and Drug Administration is recommending that doctors should consider living donors of HCT/Ps: ineligible if they were diagnosed with Zika virus infection, were in an area with active Zika virus transmission, or had sex with a male with either of those risk factors, within the past six months. Donors of umbilical cord blood, placenta, or other gestational tissues should be considered ineligible if they have had any of the above risk factors at any point during their pregnancy. Meanwhile, deceased donors: should be considered ineligible if they were diagnosed with Zika virus infection in the past 6-months.
A 6-months deferral period was selected because of the limited data available on the length of time the virus can persist in all tissues. Zika virus has been detected in tissues and body fluids after the virus is no longer detectable in the blood stream, and has been detected in semen possibly up to 10 weeks after the onset of symptoms. Given the uncertainty, 6-months was determined to provide the appropriate level of caution.
The FDA continues to prioritize the development of blood donor screening and diagnostic tests that may be useful for identifying the presence of or recent infection with the virus, prepare to evaluate the safety and efficacy of investigational vaccines and therapeutics that might be developed, and review technology that may help suppress populations of the mosquitoes that can spread the virus.