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The current range of the root vole (Microtus oeconomus) in Europe has been shaped by climate changes, including the last glaciation. In Central Europe there are two isolated subspecies: M. oeconomus mehelyi and M. oeconomus arenicola occurring in the Pannonian lowland and the Netherlands respectively. M. oeconomus stimmingi is present in the northern part of Central Europe in the continuous range of the species distribution. To establish the influence of the postglacial isolation on the subspecies performance, we sampled 192 individuals at seven sites from the three geographic regions. Individuals were genotyped at 14 microsatellite loci highly polymorphic for all subspecies studied. This is the first extensive research presenting the diversity of M. oeconomus mehelyi from Central Europe at the molecular level. Its genetic diversity (Ar = 6.6, SD = 0.4) as well as effective population size (LDNe = 170, SD = 62) were significantly lower than in the other two subspecies, their average Ar = 7.6, SD = 0.2 and LDNe = 504, SD = 134, suggesting M. oeconomus mehelyi is most threatened with extinction. None of the subspecies showed significant genetic bottleneck signatures. The differential analysis of the genetic structure of various subgroups resulting from clustering analysis was performed to reveal the genetic relationships among individuals within and between geographic regions. We found a closer relation of M. oeconomus stimmingi with each of the isolated subspecies than between them. Moreover, we detected a clear substructure in Pannonian M. oeconomus (two subgroups), that could result from more than one colonization episode.

Puumala hantavirus (PUUV) is the most common and widespread hantavirus in Europe and is associated with a mild form of haemorrhagic fever with renal syndrome in humans, called nephropathia epidemica. This study presents the molecular characterization of PUUV circulating in bank voles in two regions of the Netherlands. Most human cases of hantavirus infection are from these two regions. Phylogenetic analysis of the (partial) S, M and L-segments indicated that the Dutch strains belong to the CE lineage, which includes PUUV strains from France, Germany and Belgium. We have identified two distinct groups of PUUV, corresponding with their geographic origin and with adjoining regions in neighbouring countries.

This paper deals with modelling the relationship between human Puumala hantavirus (PUUV) infection, the abundance and prevalence of infection of the host (the bank vole), mast, and temperature. These data were used to build and parametrise generalised regression models, and parametrise them using datasets on these factors pertaining to the Netherlands. The performance of the models was assessed by considering their predictive power. Models including mast and monthly temperature performed well, and showed that mast intensity influences vole abundance and hence human exposure for the following year. Thus, the model can aid in forecasting of human illness cases, since (1) mast intensity influences the vole abundance and hence human exposure for the following year and (2) monitoring of mast is much more feasible than determining bank vole abundance.