Intensive management of Fennoscandian forests has led to a mosaic of woodlands in different stages of maturity. The main rodent host of the zoonotic Puumala hantavirus (PUUV) is the bank vole (Myodes glareolus), a species that can be found in all woodlands and especially mature forests. We investigated the influence of forest age structure on PUUV infection dynamics in bank voles.
Hantaviruses (genus Hantavirus, family Bunyaviridae) are enveloped tri-segmented negative-stranded RNA viruses each carried by a specific rodent or insectivore host species. Several different hantaviruses known to infect humans circulate in Europe. The most common is Puumala (PUUV) carried by the bank vole; another two important, genetically closely related ones are Dobrava-Belgrade (DOBV) and Saaremaa viruses (SAAV) carried by Apodemus mice (species names follow the International Committee on Taxonomy of Viruses nomenclature).
Puumala hantavirus (PUUV) is a zoonotic virus that in humans causes nephropathia epidemica (NE) in humans, a mild form of haemorrhagic fever with renal syndrome. An average of 10 000 cases are reported annually in Europe, many of which occur in Fennoscandia. The incidence of NE is connected to the distribution and population density of the the bank vole (Myodes glareolus), the main virus host. In Fennoscandia, high incidences of NE occur at 3-4 year intervals due to the characteristic population cycles of this woodland rodent.