Most hosts, including humans, are simultaneously or sequentially infected with several parasites. A key question is whether patterns of coinfection arise because infection by one parasite species affects susceptibility to others inherent differences between hosts. We used time-series data from individual hosts in natural populations analyze risk for a microparasite community, detecting large positive and negative effects other infections. Patterns remain once variations host exposure...

The fundamental role of the major histocompatibility complex (MHC) in immune recognition has led to a general consensus that characteristically high levels functional polymorphism at MHC genes is maintained by balancing selection operating through host-parasite coevolution. However, actual mechanism which operates unclear. Two hypotheses have been proposed: overdominance (or heterozygote superiority) and negative frequency-dependent selection. Evidence for these was evaluated examining...

Pathogens may be important for host population dynamics, as they can a proximate cause of morbidity and mortality. Infection in turn, dependent on the underlying condition hosts. There is clear potential synergy between infection condition: poor predisposes to infections, which further reduce so on. To provide empirical data that support this notion, we measured haematological indicators (neutrophils monocytes) (red blood cells (RBCs) lymphocytes) field voles from three populations sampled...

A key aim in epidemiology is to understand how pathogens spread within their host populations. Central this an elucidation of a pathogen's transmission dynamics. Mathematical models have generally assumed that either contact rate between hosts linearly related density (density-dependent) or independent (frequency-dependent), but attempts confirm these alternative functions been rare. Here, we fit infection equations 6 years data on cowpox virus (a zoonotic pathogen) for 4 natural populations...

Plague, a zoonosis caused by Yersinia pestis, is found in Asia, the Americas but mainly Africa, with island of Madagascar reporting almost one third human cases worldwide. In highlands Madagascar, plague transmitted predominantly two flea species which coexist on island, differ their distribution. The endemic flea, Synopsyllus fonquerniei, dominates communities rats caught outdoors, while cosmopolitan Xenopsylla cheopis, mostly houses. Additionally S. fonquerniei seems restricted to areas...

The potential of biological invasions to threaten native ecosystems is well recognized. Here we describe how an introduced species impacts on host-parasite dynamics by acting as alternative host. By sampling sites across invasion front in Ireland, quantified the influence bank vole ( Clethrionomys glareolus ) epidemiology infections caused flea-transmitted haemoparasites genus Bartonella wood mice Apodemus sylvaticus ). were detected either side but occurred exclusively mice, despite being...

SUMMARY The physiological and immunological state of an animal can be influenced by current infections infection history. Consequently, both ongoing previous affect host susceptibility to another parasite, the biology subsequent (e.g. length) impact on morbidity (pathology). In natural populations, most animals will infected a succession different parasites throughout course their lives, with probably frequent concomitant infections. relative timing experienced (i.e. sequence events),...

The importance of Ixodes ricinus in the transmission tick-borne pathogens is well recognized United Kingdom and across Europe. However, role coexisting species, such as widely distributed species trianguliceps, alternative vectors for these has received little attention. This study aimed to assess relative I. trianguliceps Anaplasma phagocytophilum Babesia microti among field voles (Microtus agrestis), which serve reservoir hosts both pathogens. While all instars feed exclusively on small...

Summary Invasions can impact on parasite communities through both the introduction of exotic species and effects invading hosts native dynamics. However, our understanding factors that influence invasive process mediate impacts parasites is limited. Using models host–parasite dynamics as a framework, we explore how probability spread for an introduced depend key parameters related to rates encounter, transmission, mortality recovery. We examine invasions may interact with diverse range...

Datasets from which wildlife contact networks of epidemiological importance can be inferred are becoming increasingly common. A largely unexplored facet these data is finding evidence spatial constraints on who has with whom, despite theoretical epidemiologists having long realized play a critical role in infectious disease dynamics. graph dissimilarity measure proposed to quantify how close an observed network being purely whereby its edges completely determined by the arrangement nodes....

1. Pathogens have been proposed as potentially important drivers of population dynamics, but while a few studies investigated the impact specific pathogens, wealth information provided by general indices health has hardly exploited. By evaluating haematological parameters in wild populations, our knowledge dynamics and infection may be better understood. 2. Here, natural populations field voles are to determine environmental host factors associated with indicators inflammatory response...

Background Plague, a zoonosis caused by Yersinia pestis, is found in Asia and the Americas, but predominantly Africa, with island of Madagascar reporting almost one third human cases worldwide. Plague's occurrence affected local climate factors which turn are influenced large-scale phenomena such as El Niño Southern Oscillation (ENSO). The effects ENSO on regional often enhanced or reduced second phenomenon, Indian Ocean Dipole (IOD). It known that IOD interact drivers disease. Yet impacts...

Summary The effect of cowpox virus on survival in two rodent hosts was investigated using nearly 4 years longitudinal data from sites. We whether an individual's probability infection influenced the surviving next month. also at population level, examining whether, addition to seasonal effects, changes prevalence explained further temporal variation rates. In bank voles, but not wood mice, individuals with high probabilities survived better than uninfected animals. At level population,...

Many zoonotic disease agents are transmitted between hosts by arthropod vectors, including fleas, but few empirical studies of host-vector-microparasite dynamics have investigated the relative importance and vectors. This study investigates 4 closely related Bartonella species their flea vectors in cyclic populations field voles (Microtus agrestis) over 3 years. The probability infestation was positively to vole density 12 months previously autumn, negatively more recent host densities,...

1 Cowpox virus is an endemic circulating in populations of wild rodents. It has been implicated as a potential cause population cycles field voles Microtus agrestis L., Britain, owing to delayed density-dependent pattern prevalence, but its impact on vole demographic parameters unknown. This study tests the hypothesis that infected with cowpox have lower probability survival than uninfected individuals. 2 The effect infection individual surviving next month was investigated using...

Estimating the rate and scale of dispersal is essential for predicting dynamics fragmented populations, yet empirical estimates are typically imprecise often negatively biased. We maximized detection events between small, subdivided populations water voles (Arvicola terrestris) using a novel method that combined direct capture-mark-recapture with microsatellite genotyping to identify parents offspring in different hence infer dispersal. validated individuals known from trapping data have...

Sublethal effects of parasitic infection, such as reductions in reproductive rate, can significantly affect host population dynamics. Here we show that wild populations both Clethrionomys glareolus (bank vole) and Apodemus sylvaticus (wood mouse), females infected with cowpox virus are likely to delay maturation therefore reproduction – most cases until the following breeding season. Some bank voles do mature their year birth but still take longer than uninfected females. Together our...

The importance of wild rodents as reservoirs zoonotic tick-borne pathogens is considered low in the United Kingdom because, studies to date, those parasitized by exophilic Ixodes ricinus ticks carry almost exclusively larvae and thus have a minor role transmission cycles. In cross-sectional study, 11 (6.7%) 163 field voles (Microtus agrestis) captured at sites Northern England were PCR-positive for Anaplasma phagocytophilum. found act hosts both larval nymphal I. all stages nidicolous tick...

Abstract Theory predicts that the impact of gene flow on genetic structure populations in patchy habitats depends its scale and demographic attributes demes (e.g. local colony sizes timing reproduction), but empirical evidence is scarce. We inferred among water voles Arvicola terrestris differed average sizes, population turnover degree patchiness. Colonies typically consisted few reproducing adults several juveniles. Twelve polymorphic microsatellite DNA loci were examined. Levels...

1 Recent studies of rodent populations have demonstrated that certain parasites can cause juveniles to delay maturation until the next reproductive season. Furthermore, a variety may share same host, and evidence is beginning accumulate showing nonindependent effects different infections. 2 We investigated consequences for host population dynamics disease-induced period no reproduction, chronic reduction in fecundity following recovery from infection (such as be induced by secondary...

The seasonality of recurrent epidemics has been largely neglected, especially where patterns are not driven by forces external to the population. Here, we use data on cowpox virus in field voles explore seasonal wildlife (variable abundance) populations and compare these with previously found humans. Timing our system was associated both number rate recruitment susceptible hosts. A plentiful sustained supply hosts throughout summer gave rise a steady infected late peak. meagre more limited...

Summary To investigate interactions between parasite species in a host, population of field voles was studied longitudinally, with presence or absence six different parasites measured repeatedly. Although trapping sessions were regular, set caught at each session, leading to incomplete profiles for all subjects. We use discrete time hidden Markov model disease transition probabilities dependent on covariates via logistic regressions. For the states other diseases given point form part...