Immunogenicity of the abbreviated one-week intradermal rabies pre-exposure prophylaxis and its boostability in health-care workers: A retrospective observational cohort study.

Rabies pre-exposure prophylaxis (PrEP) is recommended for those at high occupational risk, including health care workers (HCWs) in rabies-endemic settings. Following institutional biosafety protocols, HCWs receive a one-week, two-site intradermal (ID) PrEP regimen. This retrospective vaccination records review assessed the immunogenicity of this regimen following primary vaccination and evaluated the immune response to a booster dose administered 1-3 years later. 92 HCWs with mean baseline rabies virus neutralizing antibody (RVNA) titres of 0.13 IU/mL showed adequate seroconversion (RVNA ≥ 0.5 IU/mL) by day 14, with mean titre of 13.40 IU/mL. 39 HCWs with mean pre-booster titre of 2.76 IU/mL received a booster 1-3 years later and mean post-booster titres were 51.13 IU/mL, indicating a strong anamnestic response. The regimen elicited robust seroconversion in all HCWs and induced a strong secondary immune response, supporting the immunogenicity and long-term boostability of this shortened regimen in high-risk occupational settings.