Pseudorabies virus in North-West Italian wild boar (Sus scrofa) populations: prevalence and risk factors to support a territorial risk-based surveillance

Abstract

Although  the  eradication  of  Pseudorabies  virus  (PrV)  in  domestic  pigs  is  ongoing,  the circulation  of  this  virus  in  wild  boars  remains  a  threat  in  the  currently  unprotected, ‘low prevalence’, pig population. In this study, we reported PrV prevalence data and the influence of  possible  risk  factors  in  2  North-West  Italian  wild  boar  populations  (free  and  enclosed) with the goal of supporting the implementation of a risk-based AD surveillance system. Sera from  1,425  wild  boars  were  collected  between  2011  and  2015  and  tested  by  ELISA  for  the presence  of  PrV  antibodies;  the  overall  raw  seroprevalence  was  30.39%  (433/1,425;  CI  95% 28.01-32.85%).  A  significant  difference  was  however  observed  between  the  prevalence rates  of  the  free  range  population  (9.98%;  90/902;  CI  95%;  8.10-12.12%)  and  the  enclosed  population of La Mandria park (Piedmont, Italy) (65.58%; 343/523; CI 95%; 61.51-69.65%). In both populations a significantly higher number of adults and females were found positive to PrV  ELISA.  Specific  territorial  data  on  PrV  circulation  in  wild  boars  should  be  acquired  from other regions for guiding risk-based measures in order to reduce the threat of AD re-infection in a more cost-effective manner.