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Identifying factors that drive infection dynamics in reservoir host populations is essential in understanding human risk from wildlife-originated zoonoses. We studied zoonotic Puumala orthohantavirus (PUUV) in the host, the bank vole ( Myodes glareolus ), populations in relation to the host population, rodent and predator community and environment-related factors and whether these processes are translated into human infection incidence. We used 5-year rodent trapping and bank vole PUUV serology data collected from 30 sites located in 24 municipalities in Finland. We found that PUUV seroprevalence in the host was negatively associated with the abundance of red foxes, but this process did not translate into human disease incidence, which showed no association with PUUV seroprevalence. The abundance of weasels, the proportion of juvenile bank voles in the host populations and rodent species diversity were negatively associated with the abundance index of PUUV positive bank voles, which, in turn, showed a positive association with human disease incidence. Our results suggest certain predators, a high proportion of young bank vole individuals, and a diverse rodent community, may reduce PUUV risk for humans through their negative impacts on the abundance of infected bank voles.

There has been a significant increase in the number of reported human cryptosporidiosis cases in recent years. The aim of this study is to estimate the prevalence of Cryptosporidium spp. in wild rodents and shrews, and investigate the species and genotype distribution to assess zoonotic risk. Partial 18S rRNA gene nested-PCR reveals that 36.8, 53.9 and 41.9% of mice, voles and shrews are infected with Cryptosporidium species. The highest prevalence occurred in the Microtus agrestis (field vole) and Myodes glareolus (bank vole). Interestingly, bank voles caught in fields were significantly more often Cryptosporidium-positive compared to those caught in forests. The proportion of infected animals increases from over-wintered (spring and summer) to juveniles (autumn) suggesting acquired immunity in older animals. Based on Sanger sequencing and phylogenetic analyses, Apodemus flavicollis (yellow-necked mouse) is commonly infected with zoonotic C. ditrichi. Voles carry multiple different Cryptosporidium sp. and genotypes, some of which are novel. C. andersoni, another zoonotic species, is identified in the Craseomys rufocanus (grey-sided vole). Shrews carry novel shrew genotypes. In conclusion, this study indicates that Cryptosporidium protozoan are present in mouse, vole and shrew populations around Finland and the highest zoonotic risk is associated with C. ditrichi in Apodemus flavicollis and C. andersoni in Craseomys rufocanus. C. parvum, the most common zoonotic species in human infections, was not detected.

Small mammals are known to carryCampylobacterspp.; however, little is known about the genotypes and their role in human infections. We studied intestinal content from small wild mammals collected in their natural habitats in Finland in 2010–2017, and in close proximity to 40 pig or cattle farms in 2017. The animals were trapped using traditional Finnish metal snap traps.Campylobacterspp. were isolated from the intestinal content using direct plating on mCCDA. A total of 19% of the captured wild animals (n= 577) and 41% of the pooled farm samples (n= 227) were positive forC. jejuni, which was the onlyCampylobacterspecies identified. The highest prevalence occurred in yellow-necked mice (Apodemus flavicollis) and bank voles (Myodes glareolus) which carriedCampylobacterspp. in 66.3 and 63.9% of the farm samples and 41.5 and 24.4% of individual animals trapped from natural habitats, respectively. Interestingly, all house mouse (Mus musculus) and shrew (Sorexspp.) samples were negative forCampylobacterspp.C. jejuniisolates (n= 145) were further characterized by whole-genome sequencing. Core genome multilocus sequence typing (cgMLST) clustering showed that mouse and vole strains were separated from the rest of theC. jejunipopulation (636 and 671 allelic differences, 94 and 99% of core loci, respectively). Very little or no alleles were shared withC. jejunigenomes described earlier from livestock or human isolates. FastANI results further indicated thatC. jejunistrains from voles are likely to represent a new previously undescribed species or subspecies ofCampylobacter. Core-genome phylogeny showed that there was no difference between isolates originating from the farm and wild captured animals. Instead, the phylogeny followed the host species-association. There was some evidence (one strain each) of livestock-associatedC. jejunioccurring in a farm-caughtA. flavicollisand a brown rat (Rattus norvegicus), indicating that although small mammals may not be the original reservoir ofCampylobactercolonizing livestock, they may sporadically carryC. jejunistrains occurring mainly in livestock and be associated with disease in humans.

International audience; Ljungan virus (LV), which belongs to the Parechovirus genus in the Picornaviridae family, was first isolated from bank voles (Myodes glareolus) in Sweden in 1998 and proposed as a zoonotic agent. To improve knowledge of the host association and geographical distribution of LV, tissues from 1685 animals belonging to multiple rodent and insectivore species from 12 European countries were screened for LV-RNA using reverse transcriptase (RT)-PCR. In addition, we investigated how the prevalence of LV-RNA in bank voles is associated with various intrinsic and extrinsic factors. We show that LV is widespread geographically, having been detected in at least one host species in nine European countries. Twelve out of 21 species screened were LV-RNA PCR positive, including, for the first time, the red vole (Myodes rutilus) and the root or tundra vole (Alexandromys formerly Microtus oeconomus), as well as in insectivores, including the bicolored white-toothed shrew (Crocidura leucodon) and the Valais shrew (Sorex antinorii). Results indicated that bank voles are the main rodent host for this virus (overall RT-PCR prevalence: 15.2%). Linear modeling of intrinsic and extrinsic factors that could impact LV prevalence showed a concave-down relationship between body mass and LV occurrence, so that subadults had the highest LV positivity, but LV in older animals was less prevalent. Also, LV prevalence was higher in autumn and lower in spring, and the amount of precipitation recorded during the 6 months preceding the trapping date was negatively correlated with the presence of the virus. Phylogenetic analysis on the 185 base pair species-specific sequence of the 5 ' untranslated region identified high genetic diversity (46.5%) between 80 haplotypes, although no geographical or host-specific patterns of diversity were detected.

Yersinia enterocolitica and Yersinia pseudotuberculosis are important zoonotic bacteria causing human enteric yersiniosis commonly reported in Europe. All Y. pseudotuberculosis strains are considered pathogenic, while Y. enterocolitica include both pathogenic and nonpathogenic strains which can be divided into six biotypes (1A, 1B, and 2-5) and about 30 serotypes. The most common types causing yersiniosis in Europe are Y. enterocolitica bioserotypes 4/O:3 and 2/O:9. Strains belonging to biotype 1A are considered as nonpathogenic because they are missing important virulence genes like the attachment-invasion-locus (ail) gene in the chromosome and the virulence plasmid. The role of wild small mammals as a reservoir of enteropathogenic Yersinia spp. is still obscure. In this study, the presence of Yersinia spp. was examined from 1840 wild small mammals, including voles, mice, and shrews, trapped in Finland during a 7-year period. We isolated seven Yersinia species. Y. enterocolitica was the most common species, isolated from 8% of the animals; while most of these isolates represented nonpathogenic biotype 1A, human pathogenic bioserotype 2/O:9 was also isolated from a field vole. Y. pseudotuberculosis of bioserotype 1/O:2 was isolated from two shrews. The ail gene, which is typically only found in the isolates of biotypes 1B and 2-5 associated with yersiniosis, was frequently (23%) detected in the nonpathogenic isolates of biotype 1A and sporadically (6%) in Yersinia kristensenii isolates. Our results suggest that wild small mammals, especially voles, may serve as carriers for ail-positive Y. enterocolitica 1A and Y. kristensenii. We also demonstrate that voles and shrews sporadically excrete pYV-positive Y. enterocolitica 2/O:9 and Y. pseudotuberculosis 1/O:2, respectively, in their feces and, thus, can serve as a contamination source for vegetables by contaminating the soil.

Run to the hills : gene flow among mountain areas leads to low genetic differentiation in the Norwegian lemming

In the event of suspected releases or natural outbreaks of contagious pathogens, rapid identification of the infectious agent is essential for appropriate medical intervention and disease containment. The purpose of this study was to compare the performance of a novel portable real-time PCR thermocycler, PikoReal™, to the standard real-time PCR thermocycler, Applied Biosystems® 7300 (ABI 7300), for the detection of three high-risk biothreat bacterial pathogens: Francisella tularensis, Bacillus anthracis and Yersinia pestis. In addition, a novel confirmatory real-time PCR assay for the detection of F. tularensis is presented and validated. The results show that sensitivity of the assays, based on a dilution series, for the three infectious agents ranged from 1 to 100 fg of target DNA with both instruments. No cross-reactivity was revealed in specificity testing. Duration of the assays with the PikoReal and ABI 7300 systems were 50 and 100 min, respectively. In field testing for F. tularensis, results were obtained with the PikoReal system in 95 min, as the pre-PCR preparation, including DNA extraction, required an additional 45 min. We conclude that the PikoReal system enables highly sensitive and rapid on-site detection of biothreat agents under field conditions, and may be a more efficient alternative to conventional diagnostic methods.

The knowledge of viral shedding patterns and viraemia in the reservoir host species is a key factor in assessing the human risk of zoonotic viruses. The shedding of hantaviruses (family Bunyaviridae) by their host rodents has widely been studied experimentally, but rarely in natural settings. Here we present the dynamics of Puumala hantavirus (PUUV) shedding and viraemia in naturally infected wild bank voles (Myodes glareolus). In a monthly capture-mark-recapture study, we analysed 18 bank voles for the presence and relative quantity of PUUV RNA in the excreta and blood from 2 months before up to 8 months after seroconversion. The proportion of animals shedding PUUV RNA in saliva, urine and faeces peaked during the first month after seroconversion, but continued throughout the study period with only a slight decline. The quantity of shed PUUV in reverse transcription quantitative PCR (RT-qPCR) positive excreta was constant over time. In blood, PUUV RNA was present for up to 7 months but both the probability of viraemia and the virus load declined with time. Our findings contradict the current view of a decline in virus shedding after the acute phase and a short viraemic period in hantavirus infection - an assumption widely adopted in current epidemiological models. We suggest the life-long shedding as a means of hantaviruses to survive over host population bottlenecks, and to disperse in fragmented habitats where local host and/or virus populations face temporary extinctions. Our results indicate that the kinetics of pathogens in wild hosts may differ considerably from those observed in laboratory settings.

Source at http://dx.doi.org/10.1080/17518369.2017.1319602 The biodiversity working group of the Arctic Council has developed pan-Arctic biodiversity monitoring plans to improve our ability to detect, understand and report on long-term change in Arctic biodiversity. The Arctic fox (Vulpes lagopus) was identified as a target of future monitoring because of its circumpolar distribution, ecological importance and reliance on Arctic ecosystems. We provide the first exhaustive survey of contemporary Arctic fox monitoring programmes, describing 34 projects located in eight countries. Monitored populations covered equally the four climate zones of the species’ distribution, and there were large differences between populations in long-term trends, multi-annual fluctuations, diet composition, degree of competition with red fox and human interferences. Den density, number of active dens, number of breeding dens and litter size were assessed in almost all populations, while projects varied greatly with respect to monitoring of other variables indicative of population status, ecosystem state or ecosystem function. We review the benefits, opportunities and challenges to increased integration of monitoring projects. We argue that better harmonizing protocols of data collection and data management would allow new questions to be addressed while adding tremendous value to individual projects. However, despite many opportunities, challenges remain. We offer six recommendations that represent decisive progress toward a better integration of Arctic fox monitoring projects. Further, our work serves as a template that can be used to integrate monitoring efforts of other species, thereby providing a key step for future assessments of global biodiversity.

Understanding how host dynamics, including variations of population size and dispersal, may affect the epidemiology of infectious diseases through ecological and evolutionary processes is an active research area. Here we focus on a bank vole (Myodes glareolus) metapopulation surveyed in Finland between 2005 and 2009. Bank vole is the reservoir of Puumala hantavirus (PUUV), the agent of nephropathia epidemica (NE, a mild form of hemorrhagic fever with renal symptom) in humans.M glareoluspopulations experience multiannual density fluctuations that may influence the level of genetic diversity maintained in bank voles, PUUV prevalence and NE occurrence. We examine bank vole metapopulation genetics at presumably neutral markers and immune-related genes involved in susceptibility to PUUV (Tnf-promoter,Mhc-Drb, Tlr4,Tlr7andMx2gene) to investigate the links between population dynamics, microevolutionary processes and PUUV epidemiology. We show that genetic drift slightly and transiently affects neutral and adaptive genetic variability within the metapopulation. Gene flow seems to counterbalance its effects during the multiannual density fluctuations. The low abundance phase may therefore be too short to impact genetic variation in the host, and consequently viral genetic diversity. Environmental heterogeneity does not seem to affect vole gene flow, which might explain the absence of spatial structure previously detected in PUUV in this area. Besides, our results suggest the role of vole dispersal on PUUV circulation through sex-specific and density-dependent movements. We find little evidence of selection acting on immune-related genes within this metapopulation. Footprint of positive selection is detected atTlr-4gene in 2008 only. We observe marginally significant associations betweenMhc-Drbhaplotypes and PUUV serology, and betweenMx2genotype and PUUV genogroups. These results show that microevolutionary changes and PUUV epidemiology in this metapopulation are mainly driven by neutral processes, although the relative effects of neutral and adaptive forces could vary temporally with density fluctuations.

Francisella tularensis is a highly virulent intracellular bacterium causing the zoonotic disease tularemia. It recurrently causes human and animal outbreaks in northern Europe, including Finland. Although F. tularensis infects several mammal species, only rodents and lagomorphs seem to have importance in its ecology. Peak densities of rodent populations may trigger tularemia outbreaks in humans; however, it is still unclear to which extent rodents or other small mammals maintain F. tularensis in nature. The main objective of this study was to obtain information about the occurrence of F. tularensis in small mammals in Finland. We snap-trapped 547 wild small mammals representing 11 species at 14 locations around Finland during 6 years and screened them for the presence of F. tularensis DNA using PCR analysis. High copy number of F. tularensis-specific DNA was detected in tissue samples of five field voles (Microtus agrestis) originating from one location and 2 years. According to DNA sequences of the bacterial 23S ribosomal RNA gene amplified from F. tularensis–infected voles, the infecting agent belongs to the subspecies holarctica. To find out the optimal tissue for tularemia screening in voles, we compared the amounts of F. tularensis DNA in lungs, liver, spleen, and kidney of the infected animals. F. tularensis DNA was detectable in high levels in all four organs except for one animal, whose kidney was F. tularensis DNA-negative. Thus, at least liver, lung, and spleen seem suitable for F. tularensis screening in voles. Thus, liver, lung, and spleen all seem suitable for F. tularensis screening in voles. In conclusion, field voles can be heavily infected with F. tularensis subsp. holarctica and thus potentially serve as the source of infection in humans and other mammals.

Summary 1. More than a quarter of the world’s carnivores are threatened, often due to multiple and complex causes. Considerable research efforts are devoted to resolving the mechanisms behind these threats in order to provide a basis for relevant conservation actions. However, even when the underlying mechanisms are known, specific actions aimed at direct support for carnivores are difficult to implement and evaluate at efficient spatial and temporal scales. 2. We report on a 30-year inventory of the critically endangered Fennoscandian arctic fox Vulpes lagopus L., including yearly surveys of 600 fox dens covering 21 000 km 2 . These surveys showed that the population was close to extinction in 2000, with 40–60 adult animals left. However, the population subsequently showed a fourfold increase in size. 3. During this time period, conservation actions through supplementary feeding and predator removal were implemented in several regions across Scandinavia, encompassing 79% of the area. To evaluate these actions, we examined the effect of supplemental winter feeding and red fox control applied at different intensities in 10 regions. A path analysis indicated that 47% of the explained variation in population productivity could be attributed to lemming abundance, whereas winter feeding had a 29% effect and red fox control a 20% effect. 4. This confirms that arctic foxes are highly dependent on lemming population fluctuations but also shows that red foxes severely impact the viability of arctic foxes. This study also highlights the importance of implementing conservation actions on extensive spatial and temporal scales, with geographically dispersed actions to scientifically evaluate the effects. We note that population recovery was only seen in regions with a high intensity of management actions. 5. Synthesis and applications. The present study demonstrates that carnivore population declines may be reversed through extensive actions that target specific threats. Fennoscandian arctic fox is still endangered, due to low population connectivity and expected climate impacts on the distribution and dynamics of lemmings and red foxes. Climate warming is expected to contribute to both more irregular lemming dynamics and red fox appearance in tundra areas; however, the effects of climate change can be mitigated through intensive management actions such as supplemental feeding and red fox control.

Voles (Arvicolinae, Rodentia) are known carriers of zoonotic bacteria such as Bartonella spp. and Francisella tularensis. However, apart from F. tularensis, the bacterial microbiome of voles has not previously been determined in Finland and rarely elsewhere. Therefore, we studied liver samples from 61 voles using 16S ribosomal RNA gene PCR analysis, followed by Sanger sequencing. Twenty-three of these samples were also studied with tag-encoded pyrosequencing. The samples originated from 21 field voles (Microtus agrestis), 37 tundra voles (Microtus oeconomus), and 3 bank voles (Myodes glareolus). With the more conventional 16S rDNA PCR analysis, 90 (33%) of the recovered 269 sequence types could be identified to genus level, including Bartonella, Francisella, Mycoplasma, Anaplasma, and Acinetobacter in 31, 15, 9, 9, and 9 sequences, respectively. Seventy-five (28%) matched best with sequences of uncultured bacteria, of which 40/75 could be classified to the order Clostridiales and, more specifically, to families Lachnospiraceae and Ruminococcaceae. Pyrosequencing from 23 samples revealed comparable and similar results: clinically relevant bacterial families such as Mycoplasmataceae, Bartonellaceae, Anaplasmataceae, and Francisellaceae were recognized. These analyses revealed significant bacterial diversity in vole livers, consisting of distinct and constant sequence patterns reflecting bacteria found in the intestinal gut, but including some known zoonotic pathogens as well. The molecular bacterial sequence types determined with the two different techniques shared major similarities and verified remarkable congruency between the methods.

Understanding the dynamics of zoonotic pathogens in their reservoir host populations is a prerequisite for predicting and preventing human disease epidemics. The human infection risk of Puumala hantavirus (PUUV) is highest in northern Europe, where populations of the rodent host (bank vole, Myodes glareolus) undergo cyclic fluctuations. We conducted a 7-year capture-mark-recapture study to monitor seasonal and multiannual patterns of the PUUV infection rate in bank vole populations exhibiting a 3-year density cycle. Infected bank voles were most abundant in mid-winter months during years of increasing or peak host density. Prevalence of PUUV infection in bank voles exhibited a regular, seasonal pattern reflecting the annual population turnover and accumulation of infections within each year cohort. In autumn, the PUUV transmission rate tracked increasing host abundance, suggesting a density-dependent transmission. However, prevalence of PUUV infection was similar during the increase and peak years of the density cycle despite a twofold difference in host density. This may result from the high proportion of individuals carrying maternal antibodies constraining transmission during the cycle peak years. Our exceptionally intensive and long-term dataset provides a solid basis on which to develop models to predict the dynamic public health threat posed by PUUV in northern Europe.

To the Editor: We describe cowpox with corneal involvement in a 31-year-old atopic woman who lived in southern Finland and was unvaccinated for smallpox. In August 2009, she noticed irritation and edema in her right eye and sought care from a local physician; she started topical antimicrobial drug therapy and oral cephalexin 2 days later. Over the following week, fever developed (37.6°C –39.0°C), edema developed on half her face, the eye became increasingly painful, and visual acuity decreased. The conjunctiva was severely chemotic and hyperemic, but the cornea was clear and the other eye unaffected. Microbiologic samples taken from the eye 11 days after onset showed neither bacteria nor respiratory viruses. Orbital tomography results were normal. The patient was hospitalized, and broad-spectrum intravenous antimicrobial treatment (meropenem, vancomycin, valacyclovir, and fluconazole) was started, combined with topical corticosteroids and antimicrobial drugs. Within 2 weeks, the conjunctiva showed necrosis, and epithelial erosions appeared in the lower cornea, but visual acuity normalized (Technical Appendix Figure, panels A, B). A strong cytopathic effect was observed in Vero cells infected with conjunctival swab (Technical Appendix Table 1), but the virus was unidentifiable by routine methods. In electron microscopy, cell culture and tear fluid samples contained particles with typical orthopoxvirus (OPV) morphology. PCRs for hemagglutinin (1) and 14-kDa genes (2) verified OPV infection. Additional PCRs and sequencing confirmed zoonotic cowpox virus (CPXV) with strain designation FIN/K2009. Nucleotide sequences of the hemagglutinin, thymidine kinase, and A-type inclusion body protein genes were identical to those of CPXV strains T2000 and E1989 previously identified in Finland (3). In phylogenetic analysis (Figure), CPXV/FIN/K2009 clustered with strains from Austria and shared ancestry with vaccinia virus. OPV IgG and IgM were detected by immunofluorescence assay (3) in serum samples up to 5 months after symptom onset (Technical Appendix Table 1). Figure Phylogenetic tree of orthopoxviruses constructed on the basis of the hemagglutinin gene; boldface indicates the CPXV strain infecting the patient described in this article. The phylogeny shows that the sequence derived from this patient represents a locally ... The patient was started on intravenous polyclonal gammaglobulin and topical trifluorothymidine with in vitro anti-OPV effects; nevertheless, corneal erosions enlarged, corneal stromal edema ensued, and intraocular pressure increased (online Technical Appendix Figure, panel C), suggesting trabeculitis. Topical autologous serum drops had no effect. Periorbital edema slowly resolved, but corneal erosions persisted. Amniotic membrane transplantation (AMT) (4) was performed 2.5 months after onset. The inferior cornea melted, and the cornea lost transparency (online Technical Appendix Figure, panel D). AMT was repeated twice at 1-month intervals because of corneal thinning. At 3.5 months after symptom onset, tecovirimat (400 mg 2×/d) was given orally for 14 days. Despite treatment, ocular OPV PCR test results remained positive until 9 months after onset (Technical Appendix Table 1), and corneal melting progressed (Technical Appendix Figure, panel E). Corneal collagen cross-linking and a fourth AMT were performed at 5 months after onset with partial success (Technical Appendix Figure, panel F). At 1 year after symptom onset, corneal limbal stem cell deficiency with deep corneal neovascularization was evident. Autologous limbal stem cell transplantation from the patient’s other eye and another AMT were performed, resulting in stable corneal surface 2 months later (Technical Appendix Figure, panel G). Neovascularization regressed, the cornea cleared, and vision improved (Technical Appendix Figure, panels H, I). Cowpox is transmitted to humans sporadically from rodents or cats (5). We snap-trapped 23 wild rodents from the yard of the patient’s home and from an adjacent meadow and trapped 136 rodents from 3 other regions 30–100 km from the patient’s home (Technical Appendix Table 2). We also collected 8 environmental samples from the patient’s storehouse. In accordance with the Finnish Act on Use of Animals for Experimental Purposes (62/2006) and the Finnish Animal Experiment Board’s later decision (May 16, 2007), the animal capture technique used is not an animal experiment and requires no ethics license. Diluted blood for IFA was collected from all rodents (6), and DNA was extracted from rodent liver and lungs and from environmental samples. One vole and 1 mouse from the meadow were seropositive for OPV; however, no CPXV DNA was amplifiable in the samples from the liver, lungs, or environment (online Technical Appendix Table 2). CPXV infection may manifest in severe ocular forms along with self-limiting cutaneous pocks (5). Our patient had keratitis with no other identifiable cause but CPXV. Culture and PCR from early conjunctival samples and serology confirmed the etiologic diagnosis. Our case and that of another report (7) highlight the challenges of treating cowpox keratitis. Topical and systemic antiviral drugs and AMT appear ineffective during the acute phase. Corneal melting and scarring continued as long as CPXV was observed and until combined limbal stem cell and AMT treatment had favorable outcomes. Anamnesis of therapy-resistant keratitis should include information on rodent contacts. We dated the infection to mid-August (incubation 7–21 days). Catching OPV-IgG–positive rodents close to the patient’s home 2 months after onset showed that OPVs were circulating in the local rodent population and indicated the putative role of CPXV-infected voles as the source of infection. The latest cowpox outbreak in Central Europe involved several humans and pets (8). This patient was born in 1977, after Finland ceased smallpox vaccinations. Declining cross-reactive smallpox-vaccination immunity enables emergence of unusual cowpox infections in humans (9). Technical Appendix.Diagnostic findings of patient, laboratory findings of sampling from rodents and environment, and images of progressive disease in eye of patient with ocular cowpox, Finland. Click here to view.(150K, pdf)

Puumala hantavirus (PUUV) causes a mild form of haemorrhagic fever with renal syndrome in Europe. Seven genetic lineages of PUUV have thus far been recorded, which exhibit geographic structure within the distribution of its natural host, the bank vole (Myodes glareolus). This study presents evidence for two distinct PUUV lineages co-circulating in Latvia: one previously described from Russia and a novel one that appears to be endemic. The Latvian lineage (LAT) is considerably divergent and several amino acid markers make it easily distinguishable. Phylogenetic analysis suggested a possibility of different evolutionary histories for the PUUV genome segments of LAT. J. Med. Virol. 84:314–318, 2012. © 2011 Wiley Periodicals, Inc.

The genus Orthopoxvirus includes variola (smallpox) virus and zoonotic cowpox virus (CPXV). All orthopoxviruses (OPV) are serologically cross-reactive and cross-protective, and after the cessation of smallpox vaccination, CPXV and other OPV infections represent an emerging threat to human health. In this respect CPXV, with its reservoir in asymptomatically infected wild rodents, is of special importance. In Europe, clinical cowpox has been diagnosed in both humans and animals. The main objective of this study was to elucidate the prevalence of OPV infections in wild rodents in different parts of Eurasia and to compare the performance of three real-time polymerase chain reaction (PCR) methods in detecting OPV DNA in wildlife samples. We investigated 962 wild rodents from Northern Europe (Finland), Central Europe (Germany), and Northern Asia (Siberia, Russia) for the presence of OPV antibodies. According to a CPXV antigen-based immunofluorescence assay, animals from 13 of the 17 locations (76%) showed antibodies. Mean seroprevalence was 33% in Finland (variation between locations 0%-69%), 32% in Germany (0%-43%), and 3.2% (0%-15%) in Siberia. We further screened tissue samples from 513 of the rodents for OPV DNA using up to three real-time PCRs. Three rodents from two German and one Finnish location were OPV DNA positive. The amplicons were 96% to 100% identical to available CPXV sequences. Further, we demonstrated OPV infections as far east as the Baikal region and occurring in hamster and two other rodent species, ones previously unnoticed as possible reservoir hosts. Based on serological and PCR findings, Eurasian wild rodents are frequently but nonpersistently infected with OPVs. Results from three real-time PCR methods were highly concordant. This study extends the geographic range and wildlife species diversity in which OPV (or CPXV) viruses are naturally circulating.

Rodents might maintain tick-borne encephalitis virus (TBEV) in nature through latent persistent infections. During 2 subsequent winters, 2008 and 2009, in Finland, we detected RNA of European and Siberian subtypes of TBEV in Microtus agrestis and Myodes glareolus voles, respectively. Persistence in rodent reservoirs may contribute to virus overwintering.

Haukisalmi, V., Hardman, L. M., Foronda, P., Feliu, C., Laakkonen, J., Niemimaa, J., Lehtonen, J. T. & Henttonen, H. (2010). Systematic relationships of hymenolepidid cestodes of rodents and shrews inferred from sequences of 28S ribosomal RNA. —Zoologica Scripta, 39, 631–641. This study attempts to elucidate systematic relationships of hymenolepidid cestodes of rodents (18 species), shrews (13 species) and bats (one species) using sequences of partial 28S ribosomal RNA, with special reference to the genus Rodentolepis. The main finding is the presence of four multispecies clades of hymenolepidid cestodes showing pronounced morphological variation and frequent colonizations between unrelated hosts. Neither the hymenolepidid cestodes of shrews nor rodents were monophyletic. Also, the genus Rodentolepis sensu Vaucher in Czaplinski & Vaucher (1994, Keys to the Cestode Parasites of Vertebrates. Commonwealth Agricultural Bureaux International, Cambridge) is clearly non-monophyletic. Although rostellar morphology is obviously a key feature on specific and generic levels, on higher systematic levels it seems to be a rather poor indicator of phylogenetic affinity in hymenolepidid cestodes. The presence of clades with more than one rostellar type (armed rostellum present, rudimentary unarmed rostellum present and rostellum absent) also conflicts with the proposed subfamilial and tribal classifications of hymenolepidid cestodes. The overall evidence suggests that the recent trend of splitting hymenolepidid cestodes into multiple genera will produce a more stable and practical classification than the earlier practice of favouring a few, morphologically variable genera. New classifications of hymenolepidid cestodes should, however, consider both morphological and molecular evidence.

Background Borna disease virus (BDV) can infect many vertebrate species, including humans. BDV infection may lead to meningoencephalomyelitis in animals. An association with human neuropsychiatric diseases has been reported, but the causal relationship between BDV and human disease remains unclear. Objectives and study design To find out whether BDV is present in Finland and to look for a potential reservoir, we examined a large panel of blood samples from different vertebrate species with immunofluorescence assay. Samples from horses, cats, dogs, sheep, cattle, large predators, grouse, wild rodents and humans were included. Most positive results were confirmed by other specific methods and in other laboratories. Results and conclusions BDV-specific antibodies were detected in 10 horses, 2 cats, as well as 2 horses and 1 dog from farms housing a previously detected seropositive horse. Interestingly, BDV-specific antibodies were further detected in three wild rodents. In humans, BDV-specific antibodies were detected in a veterinarian and in two patients suspected to have a Puumala hantavirus infection. Our serological analysis suggests that BDV infects various vertebrates in Finland, including humans. Furthermore, our data indicate for the first time that BDV infects also wild rodents.

A new species, Paranoplocephala buryatiensis n. sp. (Cestoda:Anoplocephalidae), is described from the grey-sided vole Clethrionomys rufocanus (Sundevall) in the Republic of Buryatia (Russian Federation) and compared with P. longivaginata Chechulin & Gulyaev, 1998, a parasite of the red vole C. rutilus (Pallas) in the same region. P. buryatiensis n. sp. and P. longivaginata both have an exceptionally long vagina and cirrus, unique features among known species of Paranoplocephala Luhe, 1910. The new species differs from P. longivaginata primarily by its wider and more robust body, lower length/width ratio of mature proglottides, tendency of testes to occur in two separate groups, seminal receptacle of a different shape and the position of the cirrus-sac with respect to the ventral longitudinal osmoregulatory canal. The cytochrome oxidase subunit I (COI) sequence data support the independent status of these species, and show that they form a monophyletic assemblage within Paranoplocephala (sensu lato). Assuming cospeciation, an indirect calibration using host speciation dates estimated a rate of mtDNA substitution of 1.0–1.7% pairwise (0.5–0.85% per lineage) sequence divergence per million years. A faunistic review of Paranoplocephala species in C. rufocanus and C. rutilus in the Holarctic region is presented.

Puumala virus causes nephropathia epidemica, a rodent-borne zoonosis that is endemic to Europe. We sequenced the complete Puumala virus genome that was directly recovered from a person who died and compared it with those of viruses from local bank voles. The virus strain involved was neither a unique nor rare genetic variant.

Nous decrivons Paranoplocephala etholeni n. sp., parasite du Campagnol des Prairies Microtus pennsylvanicus eh Alaska et Wisconsin. Paranoplocephala etholeni est morphologiquement le plus proche de l'espece nearctique Paranoplocephala ondatrae (Rausch, 1948). Les donnees disponibles suggerent que P etholeni est une espece dont l'hote est specifique et localement rare, mais neanmoins avec une aire de repartition large et sporadique en Amerique du Nord. La decouverte de cestodes du type P. ondatrae dans des especes de campagnols Microtus spp. suggerent que cette espece peu connue est en fait une espece parasite des campagnols, plutot que du rat musque (decrit comme hote type). Un synopsis sous forme de tableau de toutes les especes de Paranoplocephala s. l. de la region holarctique avec leurs principales caracteristiques morphologiques est donne.

The majority of hantaviral infections in Denmark since 1957 have occurred on the island of Fyn. We have recently shown the presence of Puumala hantavirus (PUUV) in bank voles (Clethrionomys glareolus) on Fyn. To learn more about the distribution and prevalence of PUUV in Denmark, 310 small mammals, belonging to six rodent and two insectivore species, were trapped in four localities on Fyn and three localities on the Jutland Peninsula (mainland Denmark), where only a few cases of nephropathia epidemica (NE) have been confirmed so far. Serum samples (heart extracts) from all animals were initially analyzed for the presence of hantavirus-specific antibodies (Ab) by enzyme immunoassay, and lung tissue samples of bank voles for the presence of the viral nucleocapsid protein antigen by immunoblotting. Altogether 11 Ab-positive rodents were found, all of them bank voles from Fyn. PUUV genome sequences (nucleotides 2,168-2,569 from the medium genomic segment) were recovered by reverse transcription-polymerase chain reaction from seven bank voles. They showed an overall diversity up to 5% and formed a well-supported genetic lineage on the phylogenetic tree with a clustering of two strains from southeastern Fyn together and a separation from the one strain from western Fyn. Our data confirmed the circulation of PUUV in both the southeastern and western parts of the island, known to have the highest numbers of human NE cases.

Ljungan virus (LV) is a picornavirus originally isolated from Swedish bank voles (Myodes glareolus) in 1998. The association of LV with human disease has been debated ever since, but fundamental data on the ecology of the virus are still lacking. Here we present results of the first intensive study on the prevalence of LV in bank voles trapped in Fennoscandia (Sweden and Finland) from 2009–12 as determined by PCR. Using an LV-specific real-time reverse transcriptase PCR, LV was detected in the liver of 73 out of 452 (16.2%) individuals and in 13 out of 17 sampling sites across Sweden and Finland (mean per site prevalence 16%, SE 3%, range 0–50%). We found more infected animals in autumn compared to spring, and lighter and heavier individuals had a higher prevalence than those with intermediate body masses. The result that LV prevalence is also lower in heavier (i.e., older) animals suggests for the first time that LV infection is not persistent in rodents.

Hantaviruses are emerging viruses carried by rodents, soricomorphs (shrews and moles) and bats. In Finland, Puumala virus (PUUV) was for years the only hantavirus detected. In 2009, however, Seewis virus (SWSV) was reported from archival common shrew (Sorex araneus) samples collected in 1982 in Finland. To elucidate the diversity of hantaviruses in soricomorphs in Finland, 180 individuals were screened, representing seven species captured from 2001 to 2012: hantavirus RNA was screened using RT-PCR, and hantaviral antigen using immunoblotting with polyclonal antibodies raised against truncated SWSV nucleocapsid protein. The overall hantavirus RNA prevalence was 14% (26/180), antigen could be demonstrated in 9 of 20 SWSV RT-PCR positive common shrews. Genetic analyses revealed that four soricomorph-borne hantaviruses circulate in Finland, including Boginia virus (BOGV) in water shrew (Neomys fodiens) and Asikkala virus (ASIV) in pygmy shrew (Sorex minutus). Interestingly, on two study sites, common shrews harbored strains of two different hantaviruses: Seewis virus and a new distinct, genetically distant (identity 57% at amino acid level) virus (Altai-like virus) which clusters together with viruses in the basal phylogroup I of hantaviruses with 62–67% identity at amino acid level. This is the first evidence of coexistence of two clearly distinct hantavirus species circulating simultaneously in one host species population. The findings suggest an ancient host-switching event from a yet unknown host to S. araneus. In addition, phylogenetic analyses of partial S and M segment sequences showed that SWSV in Finland represents a unique genotype in Europe.

The parasite diversity of Norwegian lemmings Lemmus lemmus was studied in northern Fennoscandia during a moderate population peak in 1997–98. Our aim was to study the parasites of lemmings in their normal mountainous habitats in anticipation of the next great lemming migration in northern Fennoscandia into the coniferous taiga. The blood parasites ( Hepatozoon , Trypanosoma and Bartonella ) found, Frenkelia sp., which invades the brain tissue of the host, and the pulmonary fungus Chrysosporium ( Emmonsia ) sp., have been detected previously in the Norwegian lemming, but an unknown fungus, and oocysts of Eimeria spp. have not been reported from L. lemmus before. The Norwegian lemming was found to have an exceptionally species-poor helminth fauna. Only one species of cestode ( Andrya sp.) occurring in lemmings at the adult stage was found, and the cestodes of carnivores that commonly parasitize voles at the larval stage were totally absent. The distribution and abundance of vectors, and sympatric definitive hosts of parasites are predicted to have a major role in determining the parasites that lemmings will encounter during their mass movements in new habitats. However, it is predicted that parasitism by adult and larval helminths is not markedly affected by the habitat change associated with the mass migration.

Like other members of the genus HANTAVIRUS: in the family BUNYAVIRIDAE:, Puumala virus (PUUV) is thought to be co-evolving with its natural host, the bank vole Clethrionomys glareolus. To gain insight into the evolutionary history of PUUV in northern Europe during the last post-glacial period, we have studied wild-type PUUV strains originating from areas along two postulated immigration routes of bank voles to Fennoscandia. Full-length sequences of the S RNA segment and partial sequences (nt 2168-2569) of the M segment were recovered by RT-PCR directly from bank vole tissues collected at three locations in Russian Karelia and one location in Denmark. Phylogenetic analysis showed that strains from Karelia and Finland belong to the same genetic lineage, supporting the hypothesis that PUUV spread to present Finland via a Karelian land-bridge. The Danish PUUV strains showed no particularly close relatedness to any of the known PUUV strains and formed a distinct phylogenetic lineage on trees calculated for both S and M segment sequences. Although no direct link between the Danish PUUV strains and those of the southern Scandinavian lineage was found, within the S segment of Danish PUUV strains, two regions with higher similarity to either northern Scandinavian or - to a less extent - southern Scandinavian genetic lineages were revealed, suggesting evolutionary connections of their precursors.

A novel hantavirus, first detected in Siberian lemmings ( Lemmus sibiricus ) collected near the Topografov River in the Taymyr Peninsula, Siberia (A. Plyusnin et al., Lancet 347:1835–1836, 1996), was isolated in Vero E6 cells and in laboratory-bred Norwegian lemmings ( Lemmus lemmus ). The virus, named Topografov virus (TOP), was most closely related to Khabarovsk virus (KBR) and Puumala viruses (PUU). In a cross focus reduction neutralization test, anti-TOP Lemmus antisera showed titers at least fourfold higher with TOP than with other hantaviruses; however, a rabbit anti-KBR antiserum neutralized TOP and KBR at the same titer. The TOP M segment showed 77% nucleotide and 88% amino acid identity with KBR and 76% nucleotide and 82% amino acid identity with PUU. However, the homology between TOP and the KBR S segment was disproportionately higher: 88% at the nucleotide level and 96% at the amino acid level. The 3′ noncoding regions of KBR and the TOP S and M segments were alignable except for 113- and 58-nucleotide deletions in KBR. The phylogenetic relationships of TOP, KBR, and PUU and their respective rodent carriers suggest that an exceptional host switch took place during the evolution of these viruses; while TOP and KBR are monophyletic, the respective rodent host species are only distantly related.

We examined blood smears of 173 rodents and 33 shrews captured at 4 sites in the Gates of the Arctic National Park, northern Alaska, in summer 2002. Trypanosoma spp. were detected in the plasma of 5 Microtus oeconomus, 4 Microtus miurus, and 1 Lemmus trimucronatus. The trypomastigote morphology from different individuals of M. oeconomus caught at the same site and of M. miurus from different sites varied significantly. The 4 DNA sequences obtained from the blood smear positive samples contained 2 different haplotypes very similar to each other and to that of Trypanosoma microti. Of possible vectors of blood parasites, the flea Amalaraeus dissimilis was collected from M. miurus.

Reverse transcriptase polymerase chain reaction cloning and sequencing were used to determine the range of S gene/N protein variability in wild Puumala virus (PUU) strains and to study phylogenetic relationships between two groups of strains which originated from Finland and from European Russia. Analyses of the nucleotide and predicted aino acid sequences showed: (1) all PUU strains shared a common ancient ancestor; and (2) the more recent ancestors were different for the Finnish branch and the Russian branch of PUU strains. A cluster of amino acid substitutions in the N protein of Finnish strains was found; this cluster was located within a highly variable region of the molecule carrying B-cell epitopes (Vapalahti et al., J. Med. Virol., 1995, in press). Different levels of S gene/N protein diversity of PUU were revealed supporting the view of geographical clustering of genetic variants. Puumala virus from individual voles was found to be a complex mixture of closely related variant s-quasispecies. The ratio of non-silent to silent nucleotide mutations registered in the S genes/N proteins of PUU quasispecies was 4- to 16-fold higher than that in Puumala virus strains, resulting in a more wide range of quasispecies N protein sequence diversity.

We studied the seasonal prevalence of Pneumocystis carinii in Microtus agrestis (n = 289, two locations), Clethrionomys glareolus (n = 37), and Myopus schisticolor (n = 31) in southern and central Finland, in C. glareolus (n = 406) and Microtus oeconomus (n = 167) in Finnish Lapland, and in Lemmus lemmus (n = 35) in a fall sample in northern Norway. All material came from populations at peak and declining densities. The highest prevalence of P. carinii in M. agrestis in both locations in southern and central Finland was observed in November (30 and 10%). Two M. oeconomus were infected with P. carinii. No individual of the other species examined was positive for P. carinii. The prevalence and intensity of P. carinii infection in M. agrestis fed experimental low-protein diets were similar to those found in the field material.

International audience; In Europe, Dobrava-Belgrade (DOBV), Saaremaa (SAAV) and Puumala (PUUV) viruses are known to cause hemorrhagic fever with renal syndrome (HFRS). All three hantaviruses are now found in Croatia. Lung tissue samples of 315 Apodemus mice trapped in 2003-2004 were screened for the presence of hantaviral N-Ag and 20 mice (6.3%) were found either strongly positive or weak/suspected-positive. Partial sequences of hantavirus M and S segments were recovered by RT-PCR from six mice and subjected to (phylo)genetic analysis that revealed the presence of four novel strains of DOBV and one of SAAV. Curiously, one of the newly described DOBV strains was found in A. agrarius mouse, i.e. not in the traditional host, A. flavicollis mice, suggesting a spillover event. S segment sequences recovered previously from HFRS cases (Markotic et al., 2002) were confirmed as DOBV sequences; one of which appeared particularly close to the prototype Slovenian DOBV isolate. Taken together with earlier data on PUUV in Croatia, these results show a co-circulation of three European hantavirus pathogens in this country. So far, not a single SAAV sequence has been recovered from HFRS patients either in Croatia or neighbouring Slovenia and Hungary nor in Slovakia suggesting a somewhat lower fequency of acute SAAV infection in humans in this part of Europe than for example in the Baltics.

Background Sylvatic Trichinella infection has been found to be very common in Finnish wild carnivores [1], especially locally in Southern and partly Central Finland. Cannibalism and carrion feeding have been regarded as the major source of infection to red foxes and raccoon dogs. Voles have been found the major food items of red foxes [2]. They are regarded as herbivorous, but many herbivores consume animal tissues occasionally. Therefore, voles might be assumed potentially to take part in Trichinella life cycle in the wild. Microtus spp and Myodes spp have been found to be infected with Trichinella, e.g. [3]. In Finland, refuse tip rats have been found to be rather commonly infected with Trichinella spiralis [4].

Examination of ca. 500 rodents [Microtus spp., Myodes spp., Cricetulus barabensis (Pallas), Apodemus peninsulae Thomas] from 14 localities in the Republic of Buryatia (Russian Federation) revealed a minimum of 11 cestode species representing Anoplocephaloides Baer, 1923 s. str. (1 species), Paranoplocephala Lühe, 1910 s. l. (5 species), Catenotaenia Janicki, 1904 (2 species), Arostrilepis Mas-Coma & Tenora, 1997 (at least 2 species) and Rodentolepis Spasskii, 1954 (1 species). At least 5 of these species are previously unknown. The taxonomic and phylogenetic position of Buryatian Paranoplocephala-species was defined by cytochrome oxidase I (COI) sequences (mtDNA). The phylogenetic analysis also confirmed the status of Parandrya Gulyaev & Chechulin, 1996 as a junior synonym of Paranoplocephala s. l.. The species diversity of anoplocephalid cestodes was significantly lower in Buryatia and North-East Siberia (6-7 species) than in Europe (17 species). The connections of the anoplocephalid fauna of Buryatia seem to be closer with Beringia (North-East Siberia and Alaska) than with Europe. The present study demonstrated high spatial variation (patchiness) among study sites in cestodes of Buryatian rodents, with the exception of the ubiquitous Arostrilepis horrida (von Linstow, 1901)-complex.

Genomic sequences of Tula (TULV) hantavirus were recovered from tissue samples of European common voles Microtus arvalis (subspecies obscurus) captured in Kazakhstan, Central Asia. Phylogenetic analysis of the S genomic segment of Kazakh TULV strains showed that they form distinct, well supported genetic lineage and share a more ancient common ancestor with two Russian lineages of TULV. The deduced sequence of the nucleocapsid (N) protein of Kazakh TULV strains carried specific amino acid signature: T274Q276T281. The Microtus arvalis group includes several sibling species and/or subspecies in Eurasia, indicating recent and ongoing evolutionary radiation. Our data on TULV lineages in Central Asia, the region not studied for hantaviruses earlier, highlight the diversity of both Microtus host and the virus and also their co-evolution.

Dobrava virus (DOBV) carried by Apodemus flavicollis is the causative agent of severe hemorrhagic fever with renal syndrome (HFRS). DOBV was isolated from an A. flavicollis mouse trapped in northeastern Greece. This is the third DOBV cell culture isolate in the world, clustering together with other Greek DOBV sequences from HFRS patients and rodents.

The taeniid tapeworm Echinococcus multilocularis is here reported for the first time at the Svalbard Archipelago in the Norwegian Arctic. This new finding is interesting because the establishment of E. multilocularis is due to a recent anthropogenic introduction of its intermediate host – the sibling vole Microtus rossiaemeridionalis at Svalbard. The parasite itself has probably become naturally transferred to Svalbard due to migratory movements of its final host – the arctic fox Alopex lagopus between source areas for E. multilocularis in Siberia and Svalbard. We report macroscopically determined prevalence of E. multilocularis from a sample of 224 voles trapped in August in 1999 and 2000. The prevalence was among the highest ever recorded in intermediate hosts and was dependent on age and sex of the hosts approaching 100% in overwintered males. The high prevalence and the simplicity of the vole – arctic fox – E. multilocularis system at Svalbard makes it an eminent model system for further epidemiological studies.

Reverse transcription-polymerase chain reaction (RT-PCR) followed by sequence and phylogenetic analyses were used to study specimens from nine Finnish nephropathia epidemica (NE) patients admitted to hospital during the epidemic in winter 1996–1997. Blood samples from six patients were found to be positive for the partial M- and/or S-segment sequences of Puumala hantavirus (PUUV). Analyses of these sequences (nt 2168–2610 for the M segment, and nt 819–1082 for the S segment) revealed six distinct PUUV strains showing highest similarity to previously described PUUV strains from Finland: 90–95% for the S segment, and 90–99% for the M segment. Accordingly, on the phylogenetic trees calculated for both viral segments, all six human strains were placed within the Finnish genetic lineage of PUUV. Attempts were made to trace five RT-PCR-positive patients to local bank voles (Clethrionomys glareolus) infected with wild-type PUUV, and for two patients a comparative analysis of human- and rodent-originated viral sequences was undertaken. Whereas in the first case the differences between the sequences were substantial (5.7% for the S segment, and 10.8%, for the M segment), in the other case the M segment sequence recovered from the clinical specimen was 100% identical to three sequences recovered from rodent lungs, and the S sequences differed by one silent substitution only. This is the first finding of virtually identical PUUV sequences in an NE patient and a natural rodent host from the site of infection. J. Med. Virol. 59:397–405, 1999. © 1999 Wiley-Liss, Inc.

Reverse transcription-PCR was used to analyze specimens from 20 Finnish nephropathia epidemica (NE) patients hospitalized during the period from October 1994 to January 1995. Blood and/or urine sediment specimens from seven patients were found to be positive for the genome sequences of Puumala hantavirus (PUU). PCR positivity of the specimens from the patients correlated well with the HLA-DRB1*0301 and HLA B8 alleles, which previously were shown to associate with severe courses of NE. Genetic analysis of the partial M-and/or S-segment sequences obtained from three severely ill NE patients revealed three PUU strains related to but distinct from previously reported strains from Finland. The M-segment sequence of PUU from bank voles trapped near the probable site of infection for one of the patients showed 98.2% identity to that of the PUU strain obtained from the patient, suggesting a link between wild-type PUU from the natural focus and the NE case. The S-segment sequences from the patient and the bank voles, however, showed substantially lower identity (95.8%). As this difference in diversity for M and S genes (1.8 and 4.2%) is atypical for PUU genetic drift, one possibility is that the strain acquired at the putative place of infection is a reassortant one.

Hantavirus genome sequences were recovered from tissue samples of Myodes rufocanus, Microtus fortis and Microtus oeconomus captured in the Baikal area of Buryatia, Russian Federation. Genetic analysis of S- and M-segment sequences of Buryatian hantavirus strains showed that Myodes-associated strains belong to Hokkaido virus (HOKV) type while Microtus-associated strains belong to Vladivostok virus (VLAV) type. On phylogenetic trees Buryatian HOKV strains were clustered together with M. rufocanus- originated strains from Japan, China and Far-East Russia (Primorsky region). Buryatian Microtus- originated strains shared a common recent ancestor with M. fortis- originated VLAV strain from Far-East Russia (Vladivostok area). Our data (i) confirm that M. rufocanus carries a hantavirus which is similar to but distinct from both Puumala virus carried by M. glareolus and Muju virus associated with M. regulus, (ii) confirm that M. fortis is the natural host for VLAV, and (iii) suggest M. oeconomus as an alternative host for VLAV.