ATYPICAL PORCINE PESTIVIRUS – A WIDESPREAD AND HIGHLY ABUNDANT VIRUS IN THE SWEDISH WILD BOAR POPULATION. Atypical porcine pestivirus (APPV) in Swedish wild boar

The recently identified causative agent of congenital tremor in domestic piglets, atypical porcine pestivirus (APPV), has been detected in Swedish wild boar. A previous study from Sweden has described APPV in piglets suffering from congenital tremor, but the APPV situation in the wild boar population has till now been unknown. In the present study, 595 serum samples from wild boar originating from 13 counties in the south and central parts of Sweden, collected in the years between 2000 – 2018, have been investigated for APPV-specific antibodies against the APPV-glycoprotein Erns and the APPV-genome. The results revealed that APPV is highly abundant in the Swedish wild boar population; 72% (433/595) of the tested wild boars had APPV specific antibodies and, 12% (73/595) were APPV-genome positive in serum. The present study also shows that APPV has been present in the Swedish wild boar population since at least the year 2000. The viral sequences obtained from the wild boars are highly similar to APPV sequences obtained from Swedish domestic pigs suffering from congenital tremor suggesting, a viral exchange between wild boars and domestic pigs. The high proportion of viraemic and seropositive wild boar is indicative of wild boar being an important reservoir for APPV. It also raises the question whether APPV can cause chronic or persistent infections in wild boar.