Transfusion Transmitted Babesiosis in Non-Endemic States
Transfusion transmitted babesiosis is an emerging risk even in regions where Babesia is not considered endemic, raising concerns about coinfections and blood supply safety.
Transfusion-transmitted babesiosis (TTB) is a growing concern — even in states where Babesia isn’t endemic. Cases have been reported in Maryland, South Carolina, and Nebraska, serving as a reminder that blood safety extends beyond traditional tick-borne disease hotspots.
“Serve as a reminder of the potential for TTB, especially in states not endemic for Babesia,” cautions LeBel II from the Department of Pathology and Laboratory Medicine at the Medical University of South Carolina.
Transfusion Transmitted Babesiosis: Case Reports
In their article published in Transfusion, LeBel II and colleagues describe two cases of transfusion transmitted babesiosis in patients living in non-endemic regions.
One patient was asymptomatic, highlighting how difficult it can be to identify Babesia infection in the blood supply through standard donor tracing.
“The donor implicated in Cases 2 and 3 was a 30-year-old man residing in Maryland who denied any tick exposure; however, he had a history of Lyme disease symptoms and reported travel to coastal areas in Massachusetts, New York, Connecticut, Maryland, and Virginia.”
The donor tested positive by IFA and PCR 106 and 239 days after the implicated transfusions.
Asymptomatic Donors Pose the Highest Risk
Asymptomatic individuals present a major challenge for blood safety.
“Healthy, asymptomatic individuals and individuals without knowledge of babesiosis are at the highest risk for donating contaminated blood products,” LeBel II explains.
Because many infected donors are unaware of their infection, screening based on symptoms or history alone may miss cases.
Although universal screening has not been considered cost-effective, reliance on regional screening strategies may leave gaps in detection.
Why Non-Endemic States Are Still at Risk
Blood products collected in endemic areas are distributed across the United States.
As a result, clinicians in non-endemic states may not consider babesiosis in patients presenting with fever after transfusion.
“Clinicians in non-endemic states may fail to include babesiosis in the differential diagnosis of a patient with recent transfusion and fever of unknown origin,” LeBel II notes.
Limitations of Donor Screening Questionnaires
Current donor questionnaires rely heavily on patient awareness.
The standard screening question — “Have you ever had babesiosis?” — assumes that donors have been diagnosed or experienced symptoms.
However, many cases of transfusion transmitted babesiosis originate from individuals who were never diagnosed.
Clinical Perspective
Transfusion transmitted babesiosis should be considered in patients presenting with unexplained fever following blood transfusion, regardless of geographic location.
Clinicians should remain aware of the limitations of donor screening and the potential for asymptomatic infection.
Recognition of this risk is particularly important in non-endemic areas, where diagnosis may be delayed.
Clinical Takeaway
Transfusion transmitted babesiosis is not limited to endemic regions and may occur through asymptomatic donors.
Improved awareness and inclusion in the differential diagnosis may help reduce delays in diagnosis and treatment.
References
- LeBel DP 2nd, Moritz ED, O’Brien JJ, et al. Cases of transfusion-transmitted babesiosis occurring in nonendemic areas: a diagnostic dilemma. Transfusion. 2017.
Related Reading
- Babesia and Lyme: What Patients Need to Know
- Babesia Blood Donation: When Screening Finds Infection
- Babesia Blood Safety: What the FDA Workshop Revealed
Dr. Daniel Cameron, MD, MPH
Lyme disease clinician with over 30 years of experience and past president of ILADS.
Symptoms • Testing • Coinfections • Recovery • Pediatric • Prevention
maybe the donor questionnare should ask have you ever been tested for babesiosis? if yes, what strains?
if untested, screen.