Currently, Babesia microti is the highest-ranking pathogen that is transmitted by blood transfusion in the U.S. for which no donor screening is available, according to the Food and Drug Administration (FDA).
This has prompted the agency to look into screening blood donors for the parasitic disease. They are turning to the Blood Products Advisory Committee (BPAC) to look at testing from several different angles–Should antibody testing be nationally based when licensed tests are available? Maybe only in endemic areas of the country like the Northeastern, mid-Atlantic and upper Midwestern states? Should NAT testing be performed year-round?
The FDA is seeking advise with these questions and others concerning Babesia and blood product risk.
Data from the national babesiosis surveillance program and annually reported transfusion-transmitted babesiosis (TTB) cases show that the TTB-risk to U.S. blood supply is increasing making it a high priority for all applicable agencies.
Instituting NAT testing in the top five highly endemic states (Connecticut, Massachusetts, Rhode Island, New York and New Jersey) year-round in addition to antibody testing in all states plus DC is estimated to reduce TTB risk by 95%, in the best case scenario, when compared to the current no testing scenario.
Babesiosis, transmitted by a tick-vector, is caused by infections of humans with intraerythrocytic protozoa of the genus Babesia. Babesiosis can also be transmitted by transfusion of blood and blood products collected from an infected donor.
Babesiosis is characterized by a wide spectrum of clinical manifestations that depend on the host age, and its immunological and health status. In children and young healthy adults, B. microti infection leads to asymptomatic or mild disease. However, disease may be severe and even fatal in neonates, the elderly and the immuno-compromised, including cancer patients, with fatality rates of 5-20% reported.