Rabies post-exposure prophylaxis: A retrospective analysis of timing of initiation and antibody responses in a Belgian cohort

Background: We aimed to determine the timeliness of rabies post-exposure prophylaxis (PEP) and the proportion of individuals with an adequate antibody response post-PEP among those attending the Belgian national reference center. Methods: Retrospective analysis of patient records who attended our center from 2018 to 2023. Delay was defined as rabies immunoglobulin (RIG) and vaccine initiation beyond 2 calendar days after exposure. Antibodies were measured by rapid fluorescent focus inhibition test (RFFIT) after PEP in high-risk exposures. A titer ≥0.5 IU/ml was considered adequate. Results: We reviewed 317 patient records. Among individuals with inland exposure (n = 103), 85 % timely received PEP. Among travelers exposed abroad (n = 214), administration of RIG and vaccine initiation were timely in 30 % and 50 % of cases, respectively. An adequate antibody response was detected in 99.5 % (195/196) individuals. Conclusion: Substantial PEP delays among travelers were observed. The robust antibody responses suggest that routine serological follow-up is not necessary for all patients.