The US Food and Drug Administration (FDA) has released new recommendations for blood establishments to implement additional screening measures during Ebola virus outbreaks.
Since the outbreak began in 2014, the World Health Organization (WHO) estimates that there have been more than 28,000 cases of Ebola, resulting in 11,314 deaths.
The outbreak has proven particularly difficult for health authorities to quell in Guinea, Sierra Leone and Liberia. In November, WHO declared that Ebola transmission had ended in Sierra Leone, and Guinea discharged its last known Ebola patient, a baby girl, from the hospital.
However, in the same month three new cases of Ebola were reported in Liberia, where WHO has twice declared transmission had stopped, in May and September 2015.
While WHO has spearheaded the international response to the outbreak, several US agencies including FDA, the National Institutes of Health (NIH) and Centers for Disease Control and Prevention (CDC) have also played a role in the response to the epidemic.
For its part, FDA has issued 10 emergency use authorizations (EUAs) for products to treat or diagnose Ebola. The agency has also granted orphan designation to many products in development to treat Ebola, and says it has deployed "at least 12 FDA employees … to West Africa as part of the Public Health Service's team."
FDA says its new draft guidance, Recommendations for Assessment of Blood Donor Suitability, Donor Deferral and Blood Product Management in Response to Ebola Virus, is intended to be used when there is an ongoing Ebola outbreak with "widespread transmission in at least one country."
While Ebola symptoms typically present within 21 days of infection, recent analyses have demonstrated that some patients may not become symptomatic till much later. Additionally, scientists have discovered that infectious Ebola virus and viral RNA can remain present in certain parts of the body and bodily fluids for months after symptoms have resolved.
Other reports have signaled the possibility of asymptomatic infection, which could in theory lead to infection of others.
For these reasons, FDA is recommending blood establishments implement additional screening measures when the CDC declares there is widespread Ebola transmission in one or more countries.
Facilities that collect blood or blood components are instructed to ask potential donors about any history of Ebola infection, travel or residence in any country effected by an outbreak or contact with infected persons in the previous eight weeks.
FDA says that blood establishments should indefinitely defer donors who have had Ebola virus. The agency also recommends deferring donation by eight weeks for any donors who traveled to or lived in an effected country, or were in close contact with an infected individual.
The guidance goes on to advise blood establishments on what actions to take in case blood is collected from an at-risk or infected donor, including instructions on sample destruction and when to report a biological product deviation (BPD) to FDA.
WHO has identified convalescent plasma, or plasma gathered from recovered Ebola patients, as a potential treatment for the disease.
While some uncontrolled studies have been conducted to investigate the use of convalescent plasma to treat Ebola, such uses are still considered investigational by FDA and WHO. Thus, FDA says that any establishments that intend to "collect or distribute convalescent plasma intended for transfusion in the United States must submit an investigational new drug application." Similarly, device sponsors are expected to follow investigational device regulations for any new device to be used for such purposes.