Predictors of Delay in Seeking Post-Exposure Prophylaxis in Older Adults with Animal Bite Injuries: A Population-Based Study

Introduction: Animal bites are of the major health threats. Delayed post-exposure prophylaxis (PEP), especially in frail older people, may lead to mortal risks in this age group. The aim of this study was to investigate the pattern of delayed PEP in animal-bites injuries and to identify its contributing factors in older people of Tabriz city, Iran. Methods: In this cross-sectional study, the census method was used to obtain data from health records of older adults who were referred to Tabriz's Rabies Treatment Center between March 2013 and March 2018. The delay was defined as starting PEP longer than 24 hours after a suspected rabies virus exposure. The relations between delayed PEP and each of the predictors were investigated using the chi-square test in univariate analysis. The decision tree model was applied to predict the delay time of PEP. Results: A total of 322 older people with a mean age of 67.62 ± 7.18 were studied. In all, 31.7 % of the older persons victims who were bitten by an animal had a delayed PEP. Urban victims (34.1%) compared to rural (16.3 %), stray animal victims (42.0 %) compared to an owned animal-bite victim 24.6 %, all other animal bite-related victims (39.9 %) compared to dog-bite injuries (23.8%) experienced a higher frequency of delayed PEP. The decision tree revealed that animal ownership status, animal status, and animal species were the most important factors for predicting delayed PEP (p < 0.001). Conclusion: The possibility of delayed PEP in older adults bites victims, increased if the animal was ownerless and escaped. A reasonable approach to tackle this issue might be to conduct larger population studies in the future.