Epidemiological Analysis of Rabies Immunoprophylaxis and Manifestations of Natural Foci in the Transbaikal Region

Introduction: Efficacy of rabies immunoprophylaxis has been convincingly proven, but establishing the links between vaccination coverage and changes in rabies incidence in practice can be difficult if epizootics continue. Objective: To identify associations between animal and human vaccination and rabies incidence at the regional level. Materials and Methods: We conducted a retrospective descriptive epidemiological study for the years 2011 to 2024 using data from the veterinary service and the Federal Service for Surveillance on Consumer Rights Protection and Human Wellbeing (Rospotrebnadzor) on confirmed rabies cases (n = 326), vaccination coverage, and emergency department visits for animal bite injuries. We compared the periods before and after the introduction of oral fox vaccination (2011–2018 vs 2019–2024). The chi-square test, Spearman correlation, and confidence intervals for p < 0.05 (95 % CI) were used in the statistical data analysis while the Natural Earth electronic map and QGIS 3.2.1 software were used for mapping. Results: Until 2011, only dogs were vaccinated. Following the onset of epizootics among foxes (Vulpes vulpes), vaccination coverage was expanded to include farm, pet, and wild animals. Compared to 2011–2018, the growth rate of the number of doses of vaccines for various purposes was +167.3 % in 2019–2014. At the same time, the number of rabies cases decreased at a rate of –59.5 %. The share of farm animals decreased to 13–45 %, while that of wild animals increased to 45–68 %. Rabies in dogs and cats remained sporadic. A high posterior probability (p < 0.001) was demonstrated for the relationship between animal rabies and vaccination coverages of livestock and wild animals. Mapping revealed a reduction in the area of rabies-affected areas. We observed that 5,700 people received post-exposure prophylaxis annually, and 3,600 people received preventive vaccination. The incidence of animal bites ranged from 266.4 to 338.6 per 100,000 population. No cases of human rabies were registered. Conclusion: A significant correlation was established between increased vaccination coverage and the spread of rabies among animals. A change in the type of epizootics and systematic vaccination of the population contributed to the decreased risk of human rabies.