Hantavirus Seroprevalence in the Population of Saint Petersburg and the Leningrad Region, Russia.

The aim of the study was to assess the seroprevalence of hantaviruses, the causative agents of hemorrhagic fever with renal syndrome (HFRS), and their distribution to socio-demographic characteristics among the populations of Saint Petersburg and the Leningrad Region. A total of 4464 samples were analyzed, including 2265 samples from residents of Saint Petersburg and 2199 samples from residents of the Leningrad Region. Blood plasma samples were tested for specific immunoglobulin G (IgG) antibodies using enzyme-linked immunosorbent assay (ELISA). Blood samples were collected in 2023 from randomly selected volunteers. Hantavirus seroprevalence in Saint Petersburg was 5.39%, while in the Leningrad Region, it was 8.55%. In both regions, the highest proportion of seropositive individuals was found among volunteers aged ≥70 years, whereas the lowest seroprevalence was observed in the 1-17-year age group (inclusive). Seroprevalence was significantly higher in men than in women in both regions. The seroprevalence values identified in this study are comparable to those reported in similar studies in areas with a high incidence of HFRS. These findings may indicate that the true incidence of HFRS may be significantly higher than officially registered in Saint Petersburg and the Leningrad Region.