West nile fever in the north Caucasus Federal District: an assessment of epidemiological monitoring results in the contemporary period

Objective: to assess the epidemiological monitoring results of West Nile fever causative agent in the territory of the North Caucasian Federal District in the contemporary period. Materials and methods: official data from the Offices of Rospotrebnadzor for the constituent entities of the Russian Federation within the North Caucasian Federal District for the period 2010–2025 were analyzed using a comprehensive epidemiological approach. Long-term and intra-annual incidence dynamics, socio-demographic and clinical characteristics, fatality rate, spatial distribution of cases, and results of population immunity monitoring were assessed. Results: Cases of West Nile fever were registered in all constituent entities of the district. The epidemic process of West Nile fever is characterized by low reported incidence, pronounced spatial heterogeneity, and a typical seasonal pattern with a peak in August and September. A higher proportion of severe clinical forms and fatal outcomes compared with national averages was observed, which is attributable to the small number of cases and predominant detection of clinically manifest infections. Seroepidemiological studies indicate contact of the population with the pathogen and formation of population immunity, most pronounced in Stavropol Territory and the Republic of Dagestan. Conclusion. The findings confirm active circulation of West Nile virus in the North Caucasian Federal District and highlight the need to strengthen epidemiological surveillance measures and optimize seroepidemiological monitoring.

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