Detection of Reassortant Orthohantavirus puumalaense Strains in Vysokogorsky District, Republic of Tatarstan

The aim of the work was to detect Orthohantavirus puumalaense (PUUV) reassortant strains in bank voles (Clethrionomys glareolus) of the Republic of Tatarstan (RT), which are closely related to strains previously isolated from patients with hemorrhagic fever with renal syndrome (HFRS) from the RT. Materials and methods . Viral RNA was detected by RT-PCR in the lung tissue of bank voles captured in the Vysokogorsky and Pestrechinsky districts of the RT in 2023–2024. cDNA was synthesized for RT-PCR-positive samples. PUUV genome fragments of S- and M-segments were amplified using PCR, followed by sequencing (using the Sanger method and Oxford Nanopore technology) and phylogenetic analysis. Results and discussion . It has been found that 14 PUUV strains detected in bank voles from four capture sites fall into 3 clusters. In two strains from the vicinity of the village of Kinderi (cluster 2), a reassortant genome has been identified: the S-segment is closely related to strains from the Vysokogorsky district (nucleotide sequence (NS) identity is 99.1–100 %), while the M-segment is closely related to strains from the Pestrechinsky district (96.3–97.0 %). These virus strains are genetically close to reassortants previously found in HFRS patients infected by PUUV in the Vysokogorsky district of the RT. Detected in the vicinity of the village Kinderi PUUV strains appear to be of reassortant origin.