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Puumala virus (PUUV), carried by bank voles (Myodes glareolus), is the medically most important hantavirus in Central and Western Europe. In this study, a total of 523 bank voles (408 from Germany, 72 from Slovakia, and 43 from Czech Republic) collected between the years 2007-2012 were analyzed for the presence of hantavirus RNA. Partial PUUV genome segment sequences were obtained from 51 voles. Phylogenetic analyses of all three genome segments showed that the newfound strains cluster with other Central and Western European PUUV strains. The new sequences from Šumava (Bohemian Forest), Czech Republic, are most closely related to the strains from the neighboring Bavarian Forest, a known hantavirus disease outbreak region. Interestingly, the Slovak strains clustered with the sequences from Bohemian and Bavarian Forests only in the M but not S segment analyses. This well-supported topological incongruence suggests a segment reassortment event or, as we analyzed only partial sequences, homologous recombination. Our data highlight the necessity of sequencing all three hantavirus genome segments and of a broader bank vole screening not only in recognized endemic foci but also in regions with no reported human hantavirus disease cases.

Puumala virus (PUUV) is a major cause of mild to moderate haemorrhagic fever with renal syndrome and is transmitted by the bank vole (Myodes glareolus). There has been a high cumulative incidence of recorded human cases in South-eastern Germany since 2004 when the region was first recognized as being endemic for PUUV. As the area is well known for outdoor recreation and the Bavarian Forest National Park (BFNP) is located in the region, the increasing numbers of recorded cases are of concern. To understand the population and environmental effects on the seroprevalence of PUUV in bank voles we trapped small mammals at 23 sites along an elevation gradient from 317 to 1420m above sea level. Generalized linear mixed effects models(GLMEM) were used to explore associations between the seroprevalence of PUUV in bank voles and climate and biotic factors. We found that the seroprevalence of PUUV was low (6%–7%) in 2008 and 2009, and reached 29% in 2010. PUUV seroprevalence was positively associated with the local species diversity and deadwood layer, and negatively associated with mean annual temperature, mean annual solar radiation, and herb layer. Based on these findings, an illustrative risk map for PUUV seroprevalence prediction in bank voles was created for an area of the national park. The map will help when planning infrastructure in the national park (e.g., huts, shelters, and trails).

Aim We assessed the phenotypic responses of body size and organ weights oftwo small rodent species (Myodes glareolus and Apodemus flavicollis) to eleva-tion, a surrogate for temperature and other environmental conditions. Weexpected not only an increase in body size (Bergmann’s rule), but also anincrease in relative heart weight with increasing elevation (Hesse’s rule).Location The Bohemian Forest, south-eastern Germany.Methods We measured body length, body mass, and mass of the heart, lung,liver, kidneys and spleen of 386 adult specimens (188 of A flavicollis and 198of M. glareolus) from 28 localities at 300–1450 m a.s.l., and also recorded thenumber of ectoparasites. We analysed body length using linear mixed models,with site as a random factor and species, sex, population density and elevationas fixed factors, and included all two-way interactions between species and theremaining fixed variables. For the organ masses, we included body length andbody mass in the calculations to account for allometric variation of organ masswith body size. For a subset of individuals, we sequenced the mitochondrialD-loop to analyse genetic variation along the elevational gradient.Results For both species, we found no support for Bergmann’s rule. The bodysize of A. flavicollis even decreased with elevation. In contrast, the relative heartweight of both species significantly increased with elevation, thereby supportingHesse’s rule. Lung mass also increased with elevation. The mass of other inter-nal organs showed no such consistent relationship with elevation. Neither spe-cies showed genetic differentiation across the elevational gradient.Main conclusions Our results suggest that both rodent species respond toincreasing elevation by decreasing overall energy expenditure and by increasingoverall aerobic capacity. In the context of climate change, our results indicatethat biogeographers should pay more attention to the potential significance ofgenetic and/or phenotypic plasticity of relative organ mass to environmentalheterogeneity.KeywordsApodemus flavicollis, Bergmann’s rule, body size, ecogeographical rules,Germany, heart size, Hesse’s rule, Myodes glareolus, phenotypic plasticity,Rodentia.INTRODUCTIONIn responding to variation in the environment, organismshave two options. On one hand, the response may be geneticas well as epigenetic and therefore heritable. On the otherhand, organisms may respond through phenotypic plasticityin physiological, behavioural and phenological traits (Ham-mond et al., 2001; Teplitsky et al., 2008). In some circum-stances, the variation in the environment is consistent acrosslarger spatial scales, which leads to conspicuous clines(Endler, 1977). Such clines in body size, shape and colour(e.g. Bergmann’s, Allen’s and Gloger’s rules, respectively)

So far, data on the natural cycle of rickettsiae of the tick-borne spotted fever group (SFG) in Central Europe are barely available. Some studies showed the occurrence of different Rickettsia species in their arthropod vectors, but it is unclear which animals might have any kind of reservoir function. This survey was therefore set up to provide information on the occurrence of SFG rickettsiae in small mammals in Germany. A total of 124 rodents and insectivores were collected over a period of 3 years in Lower Bavaria, South-Eastern Germany. Screening for Rickettsia antibodies was performed using immunofluorescence with Rickettsia conorii and R. helvetica slides, and the comparability of sera and body fluids (transudates) was investigated in these assays. Further, real-time polymerase chain reaction (PCR) was used for screening of Rickettsial DNA in rodents and insectivores. Ear versus liver tissue was compared to evaluate the more suitable tissue for detection of specific DNA. Further, a new PCR targeting the 18S ribosomal nucleic acid was established as internal control. The results indicated that transudates are a sufficient alternative to proof infection in cases where no sera are available. Rickettsial DNA, that is, Rickettsia felis and R. helvetica, was found in seven animals with the ears proving to be a proper choice for PCR. Statistical analyses revealed that the presence of ectoparasites and the body size positively correlated with the occurrence of rickettsial DNA. Overall, our study suggests that rodents and other small mammals may act as reservoir hosts for Rickettsia. However, with the course of infection and its transmission in wild animals still unknown, further investigations are needed to better understand the natural cycle of SFG rickettsiae.

Small mammals serve as most important reservoirs for Leptospira spp., the causative agents of Leptospirosis, which is one of the most neglected and widespread zoonotic diseases worldwide. The knowledge about Leptospira spp. occurring in small mammals from Germany is scarce. Thus, this study’s objectives were to investigate the occurrence of Leptospira spp. and the inherent sequence types in small mammals from three different study sites: a forest in southern Germany (site B1); a National Park in south-eastern Germany (site B2) and a renaturalised area, in eastern Germany (site S) where small mammals were captured. DNA was extracted from kidneys of small mammals and tested for Leptospira spp. by real-time PCR. Positive samples were further analysed by duplex and conventional PCRs. For 14 positive samples, multi locus sequence typing (MLST) was performed. Altogether, 1213 small mammals were captured: 216 at site B1, 456 at site B2 and 541 at site S belonging to following species: Sorex (S.) araneus, S. coronatus, Apodemus (A.) flavicollis, Myodes glareolus, Microtus (Mi.) arvalis, Crocidura russula, Arvicola terrestris, A. agrarius, Mustela nivalis, Talpa europaea, and Mi. agrestis. DNA of Leptospira spp. was detected in 6% of all small mammals. At site B1, 25 small mammals (11.6%), at site B2, 15 small mammals (3.3%) and at site S, 33 small mammals (6.1%) were positive for Leptospira spp. Overall, 54 of the positive samples were further determined as L. kirschneri, nine as L. interrogans and four as L. borgpetersenii while five real-time PCR-positive samples could not be further determined by conventional PCR. MLST results revealed focal occurrence of L. interrogans and L. kirschneri sequence type (ST) 117 while L. kirschneri ST 110 was present in small mammals at all three sites. Further, this study provides evidence for a particular host association of L. borgpetersenii to mice of the genus Apodemus., Author Summary Leptospirosis is one of the most widespread zoonotic diseases and is caused by Leptospira spp. Small mammals often serve as maintenance hosts. We evaluated host-pathogen relations for Leptospira species and sequence types in different small mammal species captured at three German study sites. Leptospira spp. was detected in 5.9% of the captured small mammal species and at all investigated study sites. While a particular host association was observed for L. borgpetersenii to Apodemus spp., a broad host spectrum was detected for L. kirschneri which was the most common species detected in small mammals from this study. Besides this study is proving first evidence of L. kirschneri sequence types (ST) 110 and 117 as well as L. interrogans ST 24 in rodents from Germany. A focal occurrence of L. interrogans and L. kirschneri ST 117 was detected. In contrast, L. kirschneri ST 110 was present in most small mammal species at all three sites.