1785. Infectious Etiologies for Post-Donation Deferrals in a Military Blood Donation Center

BACKGROUND: The burden of transfusion-transmitted infections (TTIs) among blood recipients remains low due to strict blood donor selection as well as extensive post-donation screening. However, the military has the unique challenge of providing blood in austere environments with limited testing capabilities. This study evaluates infectious etiologies of deferred blood donors at a large military blood donation center. METHODS: All blood donors at the Armed Service Blood Bank Center-San Antonio between 2017-2022 with positive post-donation screening tests for hepatitis C (HCV), hepatitis B (HBV), HIV, HTLV-1/2, Zika, West Nile virus (WNV), T. cruzi, T. pallidum, or Babesia were evaluated. Patients were deferred from donating based on FDA criteria including a positive screen with positive confirmatory testing, a positive screen with indeterminate confirmatory testing, and a second occurrence of a positive screen with negative confirmatory testing. RESULTS: Of the 89,459 blood donors during the study period, 213 (238 per 100,000 donors) met FDA criteria for deferral. T. pallidum (n=45, 50.3 per 100,000), HCV (n=34, 38.0 per 100,000), and HBV (n=19, 21.2 per 100,000) were the most common infections seen in those with both positive screening and positive confirmatory testing. The majority of HIV (95%), Chagas (78%), HTLV-1/2 (50%) deferrals were due to indeterminate confirmatory tests following initial positive screens. The majority of deferrals for HBV were for a second occurrence of a positive screening test despite negative confirmatory testing. CONCLUSION: The rates of deferral due to positive post-donation screening for infectious diseases were low in this military cohort. In environments with limited resources, donor testing in service members should focus on HBV, HCV, and T. pallidum as the most common pathogens. Our findings also highlight the need for better diagnostics in screening donors for HIV, Chagas, and HTLV-1/2 due to frequent indeterminate confirmatory tests. DISCLOSURES: All Authors: No reported disclosures