Spatial and temporal analysis of rabies and effectiveness of the oral rabies vaccination program in Ukraine

Abstract

Rabies has been known as a lethal disease since time immemorial. Nonetheless, modern modeling estimates suggest that this infection is a cause of death of almost 60 thou people around the globe every year. In Ukraine, rabies is also a relevant problem in veterinary and human medicine. In the early 21st century, the epizootic situation regarding this infection was characterized as intense with periodic disease outbreaks. As of now, the most effective modern way to combat rabies is oral vaccination of wild carnivores against rabies. In 2018, a large-scale campaign of vaccination of feral carnivores began in Ukraine. To identify the efficacy of this anti-epizootic event, we used a complex approach that included the use of all the control elements: surveillance of rabies spread, assessment of tetracycline marker, and identification of the immunity to rabies virus in foxes in the area of vaccination. In 2022, due to the Russian military invasion of Ukraine, the oral vaccination of wild animals was not conducted. Therefore, complex assessment of efficacy of vaccination is necessary to monitor achievements of the Veterinary Service of Ukraine in combating this infection. This paper, based on our epizootic, histological, and serological studies, presents the trends of spread of rabies cases in Ukraine, which were confirmed in laboratory studies in 2018–2022. Also, the paper demonstrates the downward dynamics of rabies in all species of the animals. Analysis of the efficacy of the oral vaccination campaign of wild carnivores against rabies revealed its efficiency. At the same time, to achieve the best effect, oral vaccination of wild carnivores against rabies should be carried out twice a year – in spring and autumn. Extending the analysis to include domestic carnivores (dogs and cats) revealed problems in the current system of rabies prophylaxis