Clinical and epidemiological aspects of hemorrhagic fever with renal syndrome in the Primorsky Krai

Objective. To assess the epizootic and clinical-epidemiological situation regarding the incidence of hemorrhagic fever with renal syndrome in the Primorsky Krai in the period 2019–2023. Materials and methods. A retrospective clinical and epidemiological study of the incidence of hemorrhagic fever with renal syndrome enrolled 149 patients. The epizootic process in populations of small mammals in natural and synanthropic foci was examined according to generally accepted methodologies. Results. The activity of natural foci of hemorrhagic fever with renal syndrome, caused by the circulation of three orthohantaviruses (Hantaan virus and its Amur and Seoul genotypes), remains significant, with a predominance of the Amur carrier in the body of the Korean field mouse. This occurs despite a clear downward trend in the incidence (from an average annual rate of 4.9 to 1.6 per 100,000 population in 2019). Severe and complicated forms of the infection notably prevailed (23.5 %), with high mortality rates (up to 11.5 % in 2023). Some clinical and pathogenetic prognostic criteria for the severity of hemorrhagic fever with renal syndrome were identified in the early stages of the disease. Conclusion. The severity of the disease course and difficulties in primary diagnosis define the hemorrhagic fever with renal syndrome to be a significant public health concern in the region.