Seroprevalence of pestivirus in Eurasian tundra reindeer in Finland, Sweden, Norway, Iceland and Russian Federation

Reindeer herding is of great importance for the indigenous people of the Fennoscandia peninsula and northern Russia. There are also free-ranging feral populations of reindeer in Finland, Iceland, Norway and Russian Federation. The genus Pestivirus contains several viral species that infect ungulates and often show capacity to transmit between different host species. Sera from 520 Eurasian tundra reindeer (Rangifer tarandus tarandus) from Finland, Sweden, Norway, Iceland and Russian Federation were analysed and the prevalence of pestivirus-specific antibodies was determined. Seropositivity proportion was 48.5% for Sweden and 41.2% for Norway, but only 1.6% for Iceland and 2.5% for Finland. All Russian reindeer investigated were seronegative. Pan-pestivirus RT-PCR of seronegative animals (n = 156) from seropositive herds confirmed their negative status. These results indicate unexpectedly non-uniform circulation of an as yet uncharacterised pestivirus in Eurasian reindeer populations. The high seroprevalence in some regions warrants further studies of pestivirus infection dynamics, effects on reindeer health and population dynamics.