Endemic hantavirus infection impairs the winter survival of its rodent host

University of Helsinki, Helsinki, Uusimaa, Finland
Ecology (Impact Factor: 5). 09/2007; 88(8):1911-6. DOI: 10.1890/06-1620.1
Source: PubMed

ABSTRACT The influence of pathogens on host fitness is one of the key questions in infection ecology. Hantaviruses have coevolved with their hosts and are generally thought to have little or no effect on host survival or reproduction. We examined the effect of Puumala virus (PUUV) infection on the winter survival of bank voles (Myodes glareolus), the host of this virus. The data were collected by monitoring 22 islands over three consecutive winters (a total of 55 island populations) in an endemic area of central Finland. We show that PUUV infected bank voles had a significantly lower overwinter survival probability than antibody negative bank voles. Antibody negative female bank voles from low-density populations living on large islands had the highest survival. The results were similar at the population level as the spring population size and density were negatively correlated with PUUV prevalence in the autumn. Our results provide the first evidence for a significant effect of PUUV on host survival suggesting that hantaviruses, and endemic pathogens in general, deserve even more attention in studies of host population dynamics.

Download full-text


Available from: Eva R Kallio, Jun 16, 2015
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Many viruses significantly impact human and animal health. Understanding the population dynamics of these viruses and their hosts can provide important insights for epidemiology and virus evolution. Puumala virus (PUUV) is a European hantavirus that may cause regional outbreaks of hemorrhagic fever with renal syndrome in humans. Here, we analyzed the spatiotemporal dynamics of PUUV circulating in local populations of its rodent reservoir host, the bank vole (Myodes glareolus) during eight years. Phylogenetic and population genetic analyses of all three genome segments of PUUV showed strong geographical structuring at a very local scale. There was a high temporal turnover of virus strains in the local bank vole populations but several virus strains persisted through multiple years. Phylodynamic analyses showed no significant changes in the local effective population sizes of PUUV, although vole numbers and virus prevalence fluctuated widely. Microsatellite data demonstrated also a temporally persisting subdivision between local vole populations, but these groups did not correspond to the subdivision in the virus strains. We conclude that restricted transmission between vole populations and genetic drift play important roles in shaping the genetic structure and temporal dynamics of PUUV in its natural host which has several implications for zoonotic risks of the human population.This article is protected by copyright. All rights reserved.
    Evolutionary Applications 04/2015; DOI:10.1111/eva.12263 · 4.57 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Rodents are the most abundant order of living mammals, distributed on every continent except Antarctic and represent 43 % of all mammalian species. Beside causing food losses and infrastructural damage, rodents can harbour pathogens that may cause serious problems to human and animal health. Unfortunately, rodent-associated problems are not an issue of the past as some may have thought, even not in the developed world. This chapter describes four factors that determine the risk and severity of human infection by zoonotic pathogens of rodents: human behaviour, human health condition, rodent ecology & behaviour and pathogen ecology & persistence. It provides an overview of these factors, their interrelation and also some directions for further research. Main conclusion of this chapter is that although science has come a long way already and we have won some small victories over the rodents, the game of cat (i.e. humans) and mouse is far from being settled. The order of Rodentia is the most abundant and diversified order of living mammals and represents in total about 43 % of all mammalian species (Wilson and Reed-er 1993; Huchon et al. 2002). Rodents are distributed on every continent except Antarctica and include many of the most abundant mammals. For many centuries, opportunistic rodent species have been considered as serious pests because of the damage they cause to crops, stored produce or infrastructure and the role they play in the transmission of pathogens to humans and livestock. Improved public sanitation conditions like safe drinking water, the introduction of sewers and the development of efficient anticoagulant rodenticides in the 1950s resulted in an improved public health situation and created the illusion that rodent-associated problems in the developed world had become an issue of the past. More recently, however, the concern about rodents in both the developing and developed world has grown again because of various reasons. These reasons are the following: 629
    Zoonoses - Infections Affecting Humans and Animals, 1 edited by Andreas Sing, 01/2015: chapter 24: pages 629-641; Springer., ISBN: 978-94-017-9457-2
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Long-term field studies on parasite communities are rare but provide a powerful insight into the ecological and evolutionary processes shaping host-parasite interactions. The aim of our study was to identify the principal factors regulating long-term trends in the haemoparasite communities of bank voles, and to this end, we sampled three semi-isolated populations of bank voles (n = 880) in 1999, 2002, 2006 and 2010 in the Mazury lake district region of NE Poland. Overall, 90.8 % of the bank voles harboured at least one of the species of haemoparasites studied. Whilst overall prevalence (all species combined) did not vary significantly between the surveys, different temporal changes were detected among voles in each of the three sites. In voles from Urwitałt, prevalence increased consistently with successive surveys, whereas in Tałty, the peak years were 2002 and 2006, and in Pilchy, prevalence oscillated without a clear pattern. Across the study, bank voles harboured a mean of 1.75 ± 0.034 haemoparasite species, and species richness remained stable with no significant between-year fluctuations or trends. However, each of the five constituent species/genera showed a different pattern of spatio-temporal changes. The overall prevalence of Babesia microti was 4.9 %, but this varied significantly between years peaking in 2006 and declining again by 2010. For Bartonella spp., overall prevalence was 38.7 %, and this varied with year of study, but the temporal pattern of changes differed among the three sites. The overall prevalence of Haemobartonella (Mycoplasma) was 68.3 % with an increase in prevalence with year of study in all three sites. Hepatozoon erhardovae had an overall prevalence of 46.8 % but showed a marked reduction with each successive year of the study, and this was consistent in all three sites. The overall prevalence of Trypanosoma evotomys was 15.4 % varying significantly between sites, but showing temporal stability. While overall prevalence of all haemoparasites combined and species richness remained stable over the period of study, among the five haemoparasites, the pattern of spatiotemporal changes in prevalence and abundance of infections differed depending on parasite species. For some genera, host age was shown to play an important role, but a significant effect of host sex was found only for Haemobartonella spp.
    Microbial Ecology 03/2014; 68(2). DOI:10.1007/s00248-014-0390-9 · 3.12 Impact Factor