Epidemiological Analysis of the Effectiveness of Rabies Post-Exposure Prophylaxis in the Russian Federation (2001–2018)

Abstract

Relevance. Post-exposure prophylaxis (PEP) is the most effective method for reducing the morbidity and mortality of human rabies. Since 2000, in Russia, domestically produced cultural purified and concentrated rabies vaccine (COCAV) and equine immunoglobulin (AIG) are used as the main drugs for PEP.Aims. To assess the epidemiological effectiveness of post-exposure rabies prophylaxis and possible causes of failure in the Russian Federation in 2001–2018.Materials & methods. A comprehensive retrospective epidemiological study of 167 cases of rabies in humans and PEP statistics in the Russian Federation was carried out. To test the hypotheses about the relationship between PEP failures and risk factors, namely (gender, age, place of residence of the sick, nature of the injuries received, source of infection), two main comparison groups were formed: «vaccinated» (n = 28) and «not vaccinated» (n = 139). In addition, we compared the groups who received PEP correctly and those vaccinated with violations of instructions. The failure rate was assessed in relation to the total number of vaccinated and the number of vaccinated after contact with rabid animals.Results. During the analyzed period, the incidence of human rabies decreased from 0.015 to 0.0013 per 100 thousand population. Of the patients, 83.2% did not receive PEP (did not apply, vaccinations were not prescribed, refused). In the group «vaccinated» in 53.6% (n = 15), the schemes of PEP prescribing and administering were violated, including in 35.7% (n = 10) of cases AIG was not administered. The rest 46.4% (n = 13), received vaccinations in accordance with the instructions. Before the end of the vaccination course, 85.7% (n = 24) fell ill; the rest fell ill with an incubation period of more than three months. Only one person received AIG and all 6 vaccine injections. The group «vaccinated» differed from the group «not vaccinated» by a higher frequency of category III injuries (χ2 = 9.99, p = 0.019) and injuries caused by wild animals, especially wolves (χ2 = 22.24, p < 0.001).Conclusions. Among people who developed rabies in 2001–2018, 16.8% received PEP. The proportion of the number of cases and the total number of those who received PEP was 1: 240.0 thousand. The failure rate of PEP after contact with rabid animals was 0.03% (excluding the nature of the contact and the animal species). More than 70% of all failures are associated with wolf and fox bites, more than 85% with category III injuries.