Combined Foci of Tularemia, Leptospirosis and Hemorrhagic Fever with Renal Syndrome in the South of the Arkhangelsk region

Abstract

Relevance. Combined foci of zoonotic infections are found in all regions of the Russian Federation. A feature of combined foci is the common biocenosis for populations of pathogens of various etiologies (bacteria, viruses, parasitic infections) and the formation of natural foci by them. Aim. Epizootological study of the territory in the south of the Arkhangelsk region for the presence of combined foci of zoonotic infections (tularemia, leptospirosis and hemorrhagic fever with renal syndrome – HFRS). Materials and methods. 135 small mammals were captured and examined in the Ustyansky district of the Arkhangelsk region. Established the species composition and mixed infection among small mammals pathogens of tularemia, leptospirosis, hemorrhagic fever with renal syndrome. Results. In the south of the Arkhangelsk Region in the Ustyansky District, in 2019, for the first time, a combined natural focus of the forest type was identified and characterized. The bank vole and the common shrew are the main carriers of the causative agents of these infections. Five species of small mammals are mixed-infected with the causative agents of these infections. Infected animals with one, two or three pathogens were simultaneously detected in all studied biotopes. This indicates the presence of a combined natural focus of tularemia, leptospirosis, and HFRS. Conclusion. The existence of a combined natural focus of tularemia, leptospirosis and HFRS in middle taiga ecosystems in the south in the Ustyansky district of the Arkhangelsk region was revealed for the first time. Thus, this area can be considered enzootic for tularemia, leptospirosis and HFRS. This focus belongs to the forest type in terms of landscape and geographical characteristics. Mixed infection of small mammals suggests the possibility of simultaneous infection with pathogens of two or more infections, not only animals, but also people located on the territory of natural foci. and non-simultaneous infection of humans with tularemia, leptospirosis and HFRS in combined foci.