Detection of Pseudorabies in Dogs in Slovenia between 2006 and 2020: From Clinical and Diagnostic Features to Molecular Epidemiology

Pseudorabies (PR) is one of the most economically important diseases in domestic pigs. Since 2010, Slovenia has been free of PR in the domestic pig population, but the disease is endemic in the wild boar population, which can pose a real threat to domestic pigs and other animal species, including dogs. Between 2006 and 2020, infections with the PR virus (PRV) were reported in two pets and three hunting dogs from Slovenia that were found to have a direct contact with the wild boar or raw wild boar or pork meat. Typical clinical signs of PRV infection, including characteristic facial itching, cytopathic effect in cell cultures, positive immunocytochemistry, and positive PCR results confirmed the presence of PRV in all five cases investigated. A phylogenetic comparison of the partial glycoprotein C (gC) genomic region revealed that the Slovenian PRV isolates belong to clade A, with 95.78-100% nucleotide identity with strains isolated from dogs, domestic pigs, and wild boars from Europe. Within phylogenetic comparison of the partial glycoprotein D (gD) and partial glycoprotein E (gE) genomic regions of Slovenian PRV isolates, 100% and 99.12%-100% nucleotide identities were detected, respectively, suggesting low diversity between the PRV strains identified in dogs in Slovenia. This study provides the first molecular characterization of PRV in dogs and suggests that similar PRV strains circulate in the wild boar populations in this geographic area.