Cowpox virus (CPXV) is a zoonotic virus and endemic in wild rodent populations
in Eurasia. Serological surveys in Europe have reported high prevalence in
different vole and mouse species. Here, we report on experimental CPXV
infections of bank voles (Myodes glareolus) from different evolutionary
lineages with a spectrum of CPXV strains. All bank voles, independently of
lineage, sex and age, were resistant to clinical signs following CPXV
inoculation, and no virus shedding was detected in nasal or buccal swabs. In-
contact control animals became only rarely infected. However, depending on the
CPXV strain used, inoculated animals seroconverted and viral DNA could be
detected preferentially in the upper respiratory tract. The highest antibody
titers and virus DNA loads in the lungs were detected after inoculation with
two strains from Britain and Finland. We conclude from our experiments that
the role of bank voles as an efficient and exclusive CPXV reservoir seems
questionable, and that CPXV may be maintained in most regions by other hosts,
including other vole species. Further investigations are needed to identify
factors that allow and modulate CPXV maintenance in bank voles and other
potential reservoirs, which may also influence spill-over infections to
accidental hosts
