Surveillance for Non-statutory Pathogens in Wild Boar Culled in the Forest of Dean 2015-2016 Report for Publication - Ahdb Pork-funded Project Cskl0070

 Faeces and serum samples collected from a subset of wild boar culled in the Forest of Dean in 2015-16 were tested for evidence of infection with, or exposure to, a selection of non-statutory endemic pathogens of GB pigs.  The findings were broadly similar to those of a similar study performed in 2013-14 except that evidence of Hepatitis E virus infection was found; this pathogen was not included in previous testing.  Serological evidence of exposure to Leptospira Bratislava was detected with a low estimated seroprevalence of 3.6%.  Evidence of Hepatitis E virus infection or exposure was detected in nearly 6% of culled wild boar. One wild boar was excreting Hepatitis E virus (HEV) and the virus was identified as genotype HEV-3 and was not typical of HEV strains reported in domestic pigs or human cases.  Analysis for spatial clustering showed that wild boar culled in one area had a significantly higher risk of being HEV positive than the risk outside of that area, suggesting a possible social group effect with HEV infection. No spatial clustering was identified in L. Bratislava positive wild boar.  No Salmonella or Brachyspira species, or porcine epidemic diarrhoea virus were detected in faeces. No antibody to porcine reproductive and respiratory syndrome virus or Mycoplasma hyopneumoniae was detected in sera. With the given population and sample sizes this provides at least 95% confidence that the prevalence of those pathogens in this wild boar population is less than 4%.  Although antibody to swine influenza or porcine epidemic diarrhoea was detected in a few wild boar in one assay for each pathogen, these results were not confirmed by other antibody assays.  The results from this study are relevant for a long-established wild boar population in a forested region of England which has a relatively low commercial pig density and should not be extrapolated to wild boar populations which exist, or could establish, in other regions.  Suggestions are given regarding future wild boar surveillance.