Cross sectional study for pestivirus infection in goats in southern Italy

Pestiviruses have a worldwide distribution where ruminants farming is extensive and infection in their hosts can vary from subclinical manifestations to severe clinical signs. Although biomolecular methods are successfully employed for pestiviruses identification, they require the presence of the virus at the time of sampling. Because persistent infection is unusual in goats and acute infection is transient, for a retrospective assessment serology is the most useful approach to evaluate pestiviruses spread among ruminants. The prevalence of pestiviruses in the Italian goat population was the main target of the study and the possible influence of the co-habitation with cattle on the seropositivity of goats was taken into account. A total of 7096 sera from healthy goats were tested using an indirect ELISA. The positive samples were confirmed with a virus neutralization (VN) test and were screened for BDV too. The ELISA assay identified 57 farms (33.13%) with positive goats and an overall seropositivity of 1.63%, higher in Calabria (1.74%, 95% CI 1.68% to 1.79%) than in Apulia (1.59%, 95% CI 1.52% to 1.66%). A higher variability among farms was observed, with a significant influence of multi-species (goat and cow) grazing. Despite the huge economic losses, the impact on small ruminant productions in Italy has not yet been assessed and pestivirus infection is largely underestimated and scarcely considered. Nevertheless, the focus on pestiviruses of small ruminants should be strengthened. Considering that pestivirus infections are often subclinical, serological surveillance, the prerequisite for the implementation of control programmes, should be strongly recommended and should be considered in any pestivirus eradication programme, especially in areas such as the Southern Italy, where small ruminants farming is predominant.