The Food and Drug Administration (FDA) has approved the first donor screening tests to screen for babesiosis, a tickborne parasite, in whole blood and plasma in efforts to protect the United States blood supply.

The Imugen Babesia microti Arrayed Fluorescent Immunoassay (AFIA) has been approved for the detection of antibodies of B. microti in human plasma samples and the Imugen Babesia microti Nucleic Acid Test (NAT) has been approved for the detection of B. microti DNA in human whole blood samples. These tests are intended to screen samples from individual human donors, including volunteers who give whole blood and blood components, as well as living organ and tissue donors. Both are in-house tests that can only be performed at the Company’s Norwood, MA facility.

Babesia parasites are transmitted by blacklegged or deer ticks, and can also be transmitted via transfusion of blood or blood components collected from an infected donor. Babesiosis is the most commonly reported transfusion-transmitted parasitic infection in the country with B. microti being the main species that causes infection. For patients with a weakened immune system, B. microti infection may be severe or life-threatening.  

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Use of investigational Babesia donor testing since 2012 has led to the removal of a significant number of infected samples from the blood supply. Data from these tests and from other studies performed by the manufacturer showed that the tests are effective in screening donors for B. microti infection. The FDA is planning to issue recommendations for reducing the risk of transfusion-transmitted babesiosis later this year. 

“While babesiosis is both preventable and treatable, until today, there was no way to screen for infections amongst blood donors,” said Peter Marks, MD, PhD, director of the FDA’s Center for Biologics Evaluation and Research. “Today’s actions represent the first approvals of Babesia detection tests for use in screening donors of whole blood and blood components, and other living donors.”

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