Detection of Brno loanvirus (Loanvirus brunaense) in common noctule bats (Nyctalus noctula) in Southern Russia

Hantaviruses that infect humans are rodent-derived viruses with zoonotic potential. Several studies show that before emerging in rodents hantaviruses could emerge in bats, which makes it important to study bat-derived hantaviruses. In this study, we performed PCR screening of hantaviruses in samples from common noctules (Nyctalus noctula [182 fecal and 81 blood serum samples]), parti-coloured bats (Vespertilio murinus [41 fecal samples]), Kuhl's pipistrelles (Pipistrellus kuhlii [15 fecal samples]), and serotine bats (Eptesicus serotinus [8 fecal samples]) from Rostov Bat Rehabilitation Center (Rostov-on-Don, Russia) and phylogenetic analysis of detected viruses. As a result, hantaviruses were detected in samples from N. noctula bats with an overall prevalence of 4.94% (4/81, 95% CI 0.22-9.66%) in blood serum samples and 1.1% (2/182, 95% CI 0-2.61%) in fecal samples. Phylogenetic analysis revealed that detected hantaviruses are highly homologic to Brno loanviruses (Loanvirus brunaense) previously discovered in N. noctula bats from Central Europe, which brings some evidence that these are the same bat-derived viruses. This study shows that Loanvirus brunaense could be species-specific to the host and has a wide area of habitat: from Central Europe to Southern Russia. These are the first findings of this virus in Southern Russia and Ciscaucasus/Fore-Caucasus. Further studies with wider screening and genomic assays of Loanvirus brunaense in bats could reveal trends in the molecular evolution of hantaviruses and provide valuable data for the control of potential spillovers.