Evolutionary Relationships of Ljungan Virus Variants Circulating in Multi-Host Systems across Europe
Chiara Rossi,
Nicola Zadra,
Cristina Fevola,
Frauke Ecke,
Birger Hörnfeldt,
René Kallies,
Maria Kazimirova,
Magnus Magnusson,
Gert E. Olsson,
Rainer G. Ulrich,
Anne J. Jääskeläinen,
Heikki Henttonen,
Heidi C. Hauffe
Affiliations
Chiara Rossi
Department of Biodiversity and Molecular Ecology, Research and Innovation Centre, Fondazione Edmund Mach, 38098 San Michele all’Adige, TN, Italy
Nicola Zadra
Department of Biodiversity and Molecular Ecology, Research and Innovation Centre, Fondazione Edmund Mach, 38098 San Michele all’Adige, TN, Italy
Cristina Fevola
Department of Biodiversity and Molecular Ecology, Research and Innovation Centre, Fondazione Edmund Mach, 38098 San Michele all’Adige, TN, Italy
Frauke Ecke
Department of Wildlife, Fish, and Environmental Studies, Swedish University of Agricultural Sciences, 901 83 Umeå, Sweden
Birger Hörnfeldt
Department of Wildlife, Fish, and Environmental Studies, Swedish University of Agricultural Sciences, 901 83 Umeå, Sweden
René Kallies
Department of Environmental Microbiology Working Group Microbial Interaction Ecology, Helmholtz Centre for Environmental Research–UFZ, 04318 Leipzig, Germany
Maria Kazimirova
Slovak Academy of Sciences (SAS), Institute of Zoology, 845 06 Bratislava, Slovakia
Magnus Magnusson
Department of Wildlife, Fish, and Environmental Studies, Swedish University of Agricultural Sciences, 901 83 Umeå, Sweden
Gert E. Olsson
Department of Wildlife, Fish, and Environmental Studies, Swedish University of Agricultural Sciences, 901 83 Umeå, Sweden
Rainer G. Ulrich
Institute of Novel and Emerging Infectious Diseases, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, 17493 Greifswald-Insel Riems, Germany
Anne J. Jääskeläinen
HUS Diagnostic Center, HUSLAB, Clinical Microbiology, University of Helsinki and Helsinki University Hospital, FI-00029 Helsinki, Finland
Heikki Henttonen
Wildlife Ecology, Natural Resources Institute Finland (LUKE), FI-00790 Helsinki, Finland
Heidi C. Hauffe
Department of Biodiversity and Molecular Ecology, Research and Innovation Centre, Fondazione Edmund Mach, 38098 San Michele all’Adige, TN, Italy
The picornavirus named ‘Ljungan virus’ (LV, species Parechovirus B) has been detected in a dozen small mammal species from across Europe, but detailed information on its genetic diversity and host specificity is lacking. Here, we analyze the evolutionary relationships of LV variants circulating in free-living mammal populations by comparing the phylogenetics of the VP1 region (encoding the capsid protein and associated with LV serotype) and the 3Dpol region (encoding the RNA polymerase) from 24 LV RNA-positive animals and a fragment of the 5′ untranslated region (UTR) sequence (used for defining strains) in sympatric small mammals. We define three new VP1 genotypes: two in bank voles (Myodes glareolus) (genotype 8 from Finland, Sweden, France, and Italy, and genotype 9 from France and Italy) and one in field voles (Microtus arvalis) (genotype 7 from Finland). There are several other indications that LV variants are host-specific, at least in parts of their range. Our results suggest that LV evolution is rapid, ongoing and affected by genetic drift, purifying selection, spillover and host evolutionary history. Although recent studies suggest that LV does not have zoonotic potential, its widespread geographical and host distribution in natural populations of well-characterized small mammals could make it useful as a model for studying RNA virus evolution and transmission.
