Novel Porcine Parvovirus Detected in China

Researchers working in China and the US have detected a novel parvovirus, PPV4, in Chinese pig herds. The virus first appeared in China in 2009 and was found in two per cent of the herds surveyed.

18 November 2010

3 minute read

Lv Huang of the Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences and colleagues there and at Xinjiang Agricultural University, the US National Animal Disease Center in Ames and Nanjing Agricultural University have published a paper in Virology Journal on their studies on the prevalence of a new porcine parvovirus in pig herds in China.

They report that, to determine whether the novel porcine parvovirus type 4 (PPV4) recently reported in America is prevalent in China, a set of specific primers was designed and used for molecular survey of PPV4 among the clinical samples collected from various provinces of China between 2006 and 2010.

The results showed that PPV4 is present in Chinese swine herds at a rate of 2.09 per cent (12/573) among the clinical samples examined and 0.76 per cent (1/132) among the samples taken from healthy animals.

PPV4 was not detected in samples taken prior to 2009, noted the authors.

Analysis of the coding sequences showed that the Chinese and American PPV4 genome sequences are closely related with greater than 99 per cent nucleotide sequence identity. Similar to a previous study, viral genomes in head-to-tail configuration of various lengths of the non-coding region were detected.

The latest findings confirm that PPV4 is a unique recently discovered virus in pigs. Phylogenetically, PPV4 is most closely related to bovine parvovirus 2 (BPV2, which is not a Bocavirus and is not assigned to any Parvovirinae genus) and shares limited ORF1 (33.6 per cent) and ORF2 (24.5 per cent) amino acid identity. With respect to genome structure and organisation, PPV4 encodes an ORF3 in the middle of the viral genome that resembles the Bocavirus genus. However, the PPV4 ORF3 encoded protein shares minimal amino acid identity with the ORF3 encoded proteins of the Bocavirus genus, concluded Huang and co-authors.

Reference

Huang L., S-L. Zhai, A.K. Cheung, H-B. Zhang, J-X. Long and S-S. Yuan. 2010. Detection of a novel porcine parvovirus, PPV4, in Chinese swine herds. Virology Journal, 7:333. doi:10.1186/1743-422X-7-333.