Hantavirus Brno loanvirus is highly specific to the common noctule bat (Nyctalus noctula) and widespread in Central Europe.

Bat-associated hantaviruses have been detected in Asia, Africa and Europe. Recently, a novel hantavirus (Brno loanvirus, BRNV) was identified in common noctule bats (Nyctalus noctula) in the Czech Republic, but nothing is known about its geographical range and prevalence. The objective of this study was to evaluate the distribution and host specificity of BRNV by testing bats from neighbouring countries Germany, Austria and Poland. One thousand forty-seven bats representing 21 species from Germany, 464 bats representing 18 species from Austria and 77 bats representing 12 species from Poland were screened by L segment broad-spectrum nested reverse transcription-polymerase chain reaction (RT-PCR) or by BRNV-specific real-time RT-PCR. Three common noctules from Germany, one common noctule from Austria and three common noctules from Poland were positive in the hantavirus RNA screening. Conventional RT-PCR and primer walking resulted in the amplification of partial L segment and (almost) complete S and M segment coding sequences for samples from Germany and partial L segment sequences for samples from Poland. Phylogenetic analysis of these nucleotide sequences showed highest similarity to BRNV from Czech Republic. The exclusive detection of BRNV in common noctules from different countries suggests high host specificity. The RNA detection rate in common noctules ranged between 1 of 207 (0.5%; Austria), 3 of 245 (1.2%; Germany) and 3 of 20 (15%; Poland). In conclusion, this study demonstrates a broader distribution of BRNV in common noctules in Central Europe, but at low to moderate prevalence. Additional studies are needed to prove the zoonotic potential of this hantavirus and evaluate its transmission within bat populations.

Monitoring of Astroviruses, Brno-Hantaviruses, Coronaviruses, Influenza Viruses, Bornaviruses, Morbilliviruses, Lyssaviruses and Pestiviruses in Austrian Bats.

Here, we report the results of a monitoring study of bat viruses in Austria to strengthen the knowledge of circulating viruses in Austrian bat populations. In this study, we analyzed 618 oropharyngeal and rectal swab samples from 309 bats and 155 pooled tissue samples from dead bats. Samples were collected from 18 different bat species from multiple locations in Austria, from November 2015 to April 2018, and examined for astroviruses, bornaviruses, coronaviruses, hantaviruses, morbilliviruses, orthomyxoviruses (influenza A/C/D viruses), pestiviruses and rhabdoviruses (lyssaviruses) using molecular techniques and sequencing. Using RT-qPCR, 36 samples revealed positive or suspicious results for astroviruses, Brno-hantaviruses, and coronaviruses in nine different bat species. Further sequencing revealed correspondent sequences in five samples. In contrast, none of the tested samples was positive for influenza viruses A/C/D, bornaviruses, morbilliviruses, lyssaviruses, or pestiviruses.