Factors associated with delays in rabies post-exposure prophylaxis among international travelers in Barcelona

Rabies is a fatal zoonosis that is usually preventable by prompt post-exposure prophylaxis (PEP). International travellers to endemic areas may sustain animal-associated injuries (AAIs), but data on delays in PEP initiation remain scarce in Spain. We conducted a retrospective observational study of international travellers who attended the Adult Vaccination Centre of Hospital Clínic Barcelona between 1 January 2021 and 31 March 2025 after sustaining an AAI abroad. Electronic health records and vaccination registries were reviewed to collect sociodemographic data, travel details, AAI characteristics, vaccination history including PEP, and pre-travel advice. Outcomes were early vaccination (< 1 day from AAI) and delayed vaccination (≥ 3 days). Bivariate and multivariate logistic regression analyses were conducted, with sensitivity analysis using Cox regression. A total of 203 travellers met inclusion criteria. Median age was 31 years (IQR 26–40), 49% were female and 40% foreign-born. Most patients (89%) had never received rabies vaccination, but 19% reported pre-travel advice. The most frequent exposures were bites (75%), mainly from dogs (44%), occurring predominantly in South-East Asia (32%). The median delay to first vaccine dose was 1 day (IQR 0–6); 26% received immunoglobulin. Delayed vaccination was associated with previous vaccination and AAIs in a region different from South-East Asia or Eastern Mediterranean. Not having been previously vaccinated and male sex were associated with higher odds of early initiation. Sensitivity analysis supported these findings. While most travellers began vaccination soon after exposure, delays were frequent and linked to individual characteristics. These findings highlight the need for improved pre-travel counselling, risk communication and post-exposure management. Larger multicentric studies with standardised definitions and innovative analyses are warranted to generate stronger evidence and optimise preventive strategies for rabies in international travellers.