@phdthesis{Schmidt2022,
  author    = {Sabrina Schmidt},
  title     = {Common voles (Microtus arvalis): Important reservoir for Tula orthohantavirus and other zoonotic pathogens},
  journal    = {Feldm{\"a}use (Microtus arvalis): Wichtige Reservoirwirte f{\"u}r Tula Orthohantavirus und andere Zoonoseerreger},
  url       = {https://nbn-resolving.org/urn:nbn:de:gbv:9-opus-78456},
  pages     = {130},
  year      = {2022},
  abstract  = {The aim of this work was to characterize the distribution of TULV in European common vole populations, to clarify the host association of TULV and to investigate correlations between host population dynamics and changes in TULV prevalence. Furthermore, the potential of common voles as reservoir for other rodent-borne pathogens was examined in comparison to other rodent species. Molecular and serological analysis of rodents captured at 87 locations in Germany, France, Luxembourg, and Austria revealed TULV infections at 53.6 \% of all trapping locations. The seroprevalence in common voles was low with a mean of 8.5 \% (range: 0 – 19 \%). TULV RNA was more often detected (mean: 15.3 \%, range 0 - 37.5 \%). Field voles (Microtus agrestis) and water voles (Arvicola amphibius) were less often tested positive for TULV: mean seroprevalence was 7 \% for field voles and 6.7 \% for water voles. RNA could be detected in 5.4 \% of all tested field voles and 3.2 \% of water voles and with exception of a single field vole only when TULV-RNA-positive common voles were trapped at the same location. Those results indicate that TULV infections of field and water voles are spillover infections from sympatric TULV-infected common voles. Phylogenetic analysis revealed distinct genetic differences between TULV sequences of regions of greater geographical distance which were associated with different evolutionary common vole lineages. Furthermore, we could detect genetic differences between TULV strains from trapping sites close to each other (ca. 10 km). In a capture-mark-recapture study 1042 common voles captured in live traps in Germany were sampled as well as 225 captured in snap traps. When analyzing the seroprevalence of fluctuating common vole populations over several years and seasons we found a negative correlation between prevalence and population density in the current season but a delayed density-dependent positive correlation between the current population density and seroprevalence in the next season. However, this trend varied geographically between the four trapping locations. Usually, population density as well as seroprevalence peaked at the end of the reproductive period in autumn with the exception of Weissach (2010-2012), Jeeser (2010) and Gotha (2012) where population peaks in summer were observed. In a pilot study in Austria common voles were captured as well as three other rodent species. They were investigated not only for presence of different viruses (TULV, Dobrava- Belgrade orthohantavirus (DOBV), Puumala orthohantavirus (PUUV), Lymphocytic choriomeningitis mammarenavirus (LCMV), Cowpox virus (CPXV)) but also pathogenic bacteria and endoparasites (Leptospira spp., Toxoplasma gondii, Borrelia afzelii, Coxiella burnetii, Rickettsia spp. und Bartonella spp.). Of all four captured species, common voles were most often infected with at least one pathogen (66.7 \%), followed by wood mice (Apodemus sylvaticus) (57.7 \%), bank voles (Myodes glareolus) (35 \%) and yellow-necked field mice (Apodemus flavicollis) (34.5 \%). Common voles were also exceptionally susceptible to multiple infections: 66.7 \% of them were infected with two or three different pathogens, compared to 6.9 \% of yellow-necked field mice and 2.5 \% of bank voles. No multiple infections could be detected in wood mice. The broad geographic distribution of TULV in its reservoir host is in contrast to the rare reports of human infection but might be explained with a low pathogenicity for humans or with the low prevalence in host populations. In addition, the rare detection of human TULV infections could be a result of the used diagnostic methods. Since the reservoir population is known for its dramatic changes in population density and recurring superabundances which facilitates frequent contact to humans, TULV should more often be considered as cause for human disease in future analysis. In addition, several other zoonotic pathogens could be detected in common voles which could influence TULV infections in the reservoir host but also TULV transmission to humans and therefore deserve more attention in future research.},
  language  = {en}
}