Phylogenetic analysis of rabies virus isolates recovered from animals in Volgograd Oblast

Introduction . The Lower Volga region, including the Volgograd Oblast, remains one of Russia’s most rabies-affected areas to date. Data on the genetic diversity of rabies viruses (RABVs) currently circulating in the Volgograd Oblast are insufficient, making phylogenetic analysis of RABV isolates from this region a relevant scientific objective. Objective . The study aims to conduct a phylogenetic analysis of current RABV isolates recovered from animals in the Volgograd Oblast, based on the full-length nucleoprotein gene sequence. Materials and methods . Brain tissue samples from animals diagnosed with rabies were used. The obtained nucleotide sequences of the RABV nucleoprotein gene were analyzed using the Bayesian strict molecular clock method. The spatial distribution of RABV isolates was described using Natural Earth physical map. Results . Full-length nucleoprotein gene sequencing was performed for 13 RABV isolates collected in the Volgograd Oblast. Phylogenetic analysis revealed that the RABV population in this region comprises distinct genetic variants of genetic group C, formed at different times. Genetic relationship to the isolates from Kazakhstan, Ukraine, Moldova and Central/Southern Russia indicates intensive RABV circulation in Southern European Russia. Notably, distinct virus variants were detected on the left and right banks of the Volga River. Conclusion . All studied RABV isolates collected in the Volgograd Oblast belonged to genetic group C and exhibited high genetic diversity among variants.