High prevalence of a novel porcine bocavirus in weanling piglets with respiratory tract symptoms in China.

This study presents the first evidence of infection by a novel porcine bocavirus (PBoV) in Chinese swine herds. The PCR detection results showed that PBoV was significantly more prevalent in weanling piglets (69.7%, 69/99) with respiratory tract symptoms than that in other samples (0-13.6%) (P < 0.01). Sequence analysis showed that the partial VP1/2 genes were highly conserved (99-100% identity), and only five frequent nucleotide mutation positions existed in Chinese PBoV strains. These data indicate that PBoV might be an emerging virus for swine respiratory tract diseases. This study could help us to better understand the epidemiology of PBoV.