Teschoviruses and sapeloviruses in faecal samples from wild boar in Spain

Teschovirus and Sapelovirus are two genera of the Picornaviridae family, comprising highly variable and heterogeneous enteric viruses, commonly found in faecal samples from domestic pigs. Although both of them are also known to infect wild boar, studies on their presence in these wild suids are scarce. The present study aimed at determining the presence of porcine teschovirus (PTV) and sapelovirus (PSV) in free-living wild boar populations, as well as to study their relationships with similar viruses present in pigs. Fresh faecal samples (n=63) from wild boar were collected in Doñana Biological Reserve (SW Spain) during 2007 and 2011, and analysed using multiplex RT-PCR for the simultaneous detection and differentiation of PTV and PSV. A total of 32 samples (50.8%) presented positive PTV bands, while PSV amplicons were detected in 4 samples (6.4%). All PSV-positive samples were also positive for PTV, which indicated co-infection with both viruses. Virus isolation was successful from 6 samples, 4 of which were identified as PTV by RT-PCR, and three of these were further characterized by sequencing of the VP1 capsid protein. The remaining two isolates were negative for PTV or PSV. Genetic characterization of PSV-positive faecal samples, using the VP4 protein coding gene, was successful in 4 stool samples. Close phylogenetic relationship was found among wild boar and domestic pig strains in both PTV and PSV. More studies are needed to ascertain the epizootiological significance of these findings.