Molecular Epidemiological Investigation of Porcine kobuvirus and Its Coinfection Rate with PEDV and SaV in Northwest China

Porcine kobuvirus (PKV) has circulated throughout China in recent years. Although many studies have detected it throughout the world, its molecular epidemiology has not been characterized in northwest China. To understand its prevalence, 203 fecal samples were collected from different regions of Gansu Province and tested with reverse transcription-polymerase chain reaction. In this study, we tested these samples for PKV, porcine epidemic diarrhea virus (PEDV), and sapovirus and analyzed the amplified 2C gene fragments of PKV. Overall, 126 (62.1%) samples were positive for PKV. Of the 74 piglets samples among the 203 fecal samples, 65 (87.8%) were positive for PKV. PKV infection was often accompanied by PEDV, but the relationship between the two viruses must be confirmed. A phylogenetic analysis indicated that the PKV strains isolated from the same regions clustered on the same branches. This investigation shows that PKV infections are highly prevalent in pigs in northwest China, especially in piglets with symptoms of diarrhea.