Small White-Toothed Shrew, Crocidura suaveolens, and Its Role in the Circulation of Natural-Focal Infections in the Rostov Region

Abstract

The aim of the study was to evaluate the involvement of the small white-toothed shrew, Crocidura suaveolens , in the circulation of pathogens of natural-focal infections: tularemia, Lyme borreliosis (LB), Crimean-Congo hemorrhagic fever (CCHF), and hemorrhagic fever with renal syndrome (HFRS) in the southern part of the East European Plain in the Rostov Region (RR). Materials and methods. The findings of the epizootiological monitoring of natural-focal infections in the Rostov Region in 2019–2024 were used for the analysis. 280 specimens were caught during the specified period; 108 samples were formed, which were examined using bacteriological, molecular-genetic and immunological methods. Results and discussion. It has been found that over the past five years, the index of dominance of the small white-toothed shrew in captures has changed from a minimum (0.86 %) in 2021 to a maximum (12.10%) in 2024. It is established that the proportion of positive samples of small white-toothed shrew infected with tularemia pathogens, LB, CCHF and HFRS viruses differs in catches. During the observation period, the highest infection rate of the small white-toothed shrew was noted in regard to tularemia – 8 (7.4±2.5%) and CCHF – 6 (5.6±2.2%), the lowest – to LB – 4pathogens (3.7±1.8%) and HFRS – 3 (2.8±1.6%). According to the cartographic analysis, the administrative districts, where positive findings were identified, are located in the southwestern part of the RR (Rodionovo-Nesvetaisky, Matveevo-Kurgansky, Neklinovsky, Azovsky districts), in the northwestern part (Millerovsky district), and in the southeast (Remontnensky district). The research has showed the need for further study of significance of the small white-toothed shrew species for the circulation of pathogens of natural-focal infections as a species with high phenotypic adaptability.