Paws to Pause: Trends in blood donor deferral rates due antirabies vaccination following animal bite: A 4-year retrospective study from a tertiary care hospital blood center in Delhi

Abstract: BACKGROUND: India faces a growing challenge of an increasing stray dog population and bite incidents, leading to donor deferrals. As incidence of bite-related deferrals is rapidly rising among the top primary causes of temporary donor deferrals, this trend poses a risk to an already constrained donor pool. Deferrals frequently lead to donor attrition, hence, understanding its impact is critical for blood supply management. AIMS: To analyze prevalence, trends, and impact of antirabies vaccination (ARV) following animal bite-related donor deferrals in a tertiary care hospital blood center in Delhi from January 2021 to April 2025. STUDY DESIGN: A retrospective observational study conducted on blood donor deferrals due to ARV. MATERIALS AND METHODS: Data were extracted from donor screening logs and compared with hospital emergency room/outpatient departments (ER/OPD) records of patients postexposure prophylaxis (PEP) with ARV during the same period. Trends in ARV-related deferrals were calculated and compared with % PEP-ARV cases in ER/OPD. RESULTS: During this period, 68,296 donors registered at our blood center, of whom 7094 (10.4%) were deferred for not meeting eligibility criteria. Among these, 528 (7.7%) were temporarily deferred due to ARV. The ARV-related deferral rate showed an alarming rise of 189.5% (3.8% in 2021–11% by April 2025), correlating with the rising number of PEP-ARV cases in the ER/OPD. Notably, only 1.32% of these returned for subsequent donation, indicating substantial donor attrition. CONCLUSION: ARV-related deferrals are rising and significantly impacting donor retention. Revising deferral policies, enhancing public awareness, and integrating bite surveillance with donor data are essential to maintain the blood supply and address this growing concern.