Detection of porcine circoviruses in clinical specimens using multiplex PCR in Hubei, central China

In order to detect and simultaneously discriminate PCV1, PCV2 and PCV3, a multiplex PCR assay was developed and used to detect clinical samples in this study. Each of target genes of PCV1, PCV2 and PCV3 was amplified using the designed primers, while no other porcine viruses genes were detected. The limit of detection of the assay was 10 copies/μL of PCV1, PCV2 and PCV3. The tissue samples from eight pig farms were detected using the multiplex PCR assay. The results showed that PCV1, PCV2 and PCV3 are co-circulating in central China. The PCV1, PCV2 and PCV3 singular infection rate was 52.4% (150/286), 61.2% (175/286) and 45.1% (129/286), respectively, while the PCV1 and PCV2 co-infection rate was 11.2% (32/286), the PCV1 and PCV3 co-infection rate was 5.9% (17/286), the PCV2 and PCV3 co-infection rate was 23.4% (67/286), and the PCV1, PCV2 and PCV3 co-infection rate was 1.7% (5/286), respectively, which were 100% consistent with the sequencing method and Real-time PCR methods. It proved that this multiplex PCR assay could be used as a differential diagnostic tool for monitoring and control of PCVs in the field. The results also indicate that the PCVs infection and their co-infection are severe in Hubei Province, Central China.