Puumala hantavirus infections in bank vole populations: host and virus dynamics in Central Europe

Abstract

Background: In Europe, bank voles (Myodes glareolus) are widely distributed and can transmit Puumala virus (PUUV) to humans, which causes a mild to moderate form of haemorrhagic fever with renal syndrome, called nephropathia epidemica. Uncovering the link between host and virus dynamics can help to prevent human PUUV infections in the future. Bank voles were live trapped three times a year in 2010-2013 in three woodland plots in each of four regions in Germany. Bank vole population density was estimated and blood samples collected to detect PUUV specific antibodies.

Results: We demonstrated that fluctuation of PUUV seroprevalence is dependent not only on multi-annual but also on seasonal dynamics of rodent host abundance. Moreover, PUUV infection might affect host fitness, because seropositive individuals survived better from spring to summer than uninfected bank voles. Individual space use was independent of PUUV infections.

Conclusions: Our study provides robust estimations of relevant patterns and processes of the dynamics of PUUV and its rodent host in Central Europe, which are highly important for the future development of predictive models for human hantavirus infection risk.

Keywords: Myodes glareolus; Population dynamics; Puumala virus seroprevalence; Space use; Survival.

Fig. 1

Population dynamics of bank voles in Germany from 2010 to 2013. Estimated mean population densities ± standard deviation as individuals per hectare from three replicate woodland plots per study area (N = total number of trapped bank voles)

Fig. 2

PUUV seroprevalence in bank vole populations in two regions in Germany from 2010 to 2013. Mean seroprevalence ± standard deviation (%) in spring, summer and autumn each year estimated from three replicate woodland plots per study area. Numerical values per season are total numbers of tested individuals of all plots in each study area

Fig. 3

Seasonal effects of bank vole population density (z-transformed) on PUUV seroprevalence in the host population. Black bars on x-axis represent the distribution of population density values per trapping session

Fig. 4

Effect plots of space use as potential cause (a) and consequence (b, c) of PUUV infections (and sex-c) in bank voles. Space use of bank voles = mean minimum distance moved. Black bars on x-axis (a) represent the distribution of individual ‘mean minimum distance moved’ values

Fig. 5

Number of recaptured bank voles. Recaptures per study area (West, South) in total and per sex (f female, m male) subdivided in recaptures that remained seronegative (neg/neg) or seropositive (pos/pos), seroconverted (neg/pos) or seemed to have lost antibodies (pos/neg)

Fig. 6

Survival rates of bank voles according to PUUV seroprevalence. Mean values ± standard deviation per season of first capture

Fig. 7

Effect of individual PUUV infection status on survival of bank voles from spring (a) to summer and from summer (b) to autumn. Significant results according to Table 3 are shown