Porcine reproductive and respiratory syndrome (PRRS) is characterized by reproductive failure in sows and respiratory disease in piglets. The PRRS virus (PRRSV) is classified into type 1 (European) and type 2 (North American) genotypes according to genetic, antigenic, and pathogenic differences. We first isolated type 1 PRRSV from diseased pigs in 2009. Here, we developed a one-step real-time reverse transcription-polymerase chain reaction (qRT-PCR) assay with improved sensitivity that could detect as little as 1 × 10-2 median tissue culture infectious dose/ml of viral RNA. We tested serum samples collected from a farm that experienced an outbreak in January and September 2008, October 2009, and January 2011, and found infected pigs between January and September 2008 but not in January 2011. Further, between 2008 and 2011, we did not detect infection in pigs at 8 nearby farms or in 2,052 serum samples collected from pigs from 74 farms in 12 prefectures. We believe that our developed qRT-PCR assay can be implemented as a diagnostic tool to detect type 1 PRRSV in field samples.
(Viral Disease and Epidemiology Research Division)
References:
Iseki H. et al (2014) J. Vet. Med. Sci. 76(10):1411-1413
