Babesia nucleic acid prevalence among blood donors in southern Québec.

BACKGROUND: Tick-borne diseases are on the rise in Canada, and southern Québec is considered one of the highest-risk regions for Babesia emergence. Babesia is easily transmissible through blood transfusion and was the most common transfusion-transmitted infection in the United States before the implementation of nucleic acid testing (NAT) in 2020. Babesia NAT is not yet implemented in Canada, and prevalence studies are necessary for risk assessment. Therefore, Héma-Québec performed a new prevalence study in the summer of 2024. STUDY DESIGN AND METHODS: Whole blood and platelet donors were sampled between June 1, 2024, and October 31, 2024, in four high-risk administrative regions in southern Québec (i.e., Estrie, Montérégie, Montréal, and Mauricie-Centre-du-Québec). The samples were tested at the American Red Cross with a qualitative Babesia NAT, i.e., the Procleix Babesia assay. RESULTS: A total of 28,800 donations were collected and tested from four high-risk administrative regions of the province of Quebec. All donations tested negative for Babesia NAT. DISCUSSION: While public health data indicate that Babesia microti is emerging in southern Québec, to date, the risk of acquiring babesiosis through transfusion of blood products remains low. Partnership with public health authorities and clinicians remains essential to keep abreast of the emergence of such cases.