title: Rapid detection of a highly virulent Chinese-type isolate of Porcine Reproductive and Respiratory Syndrome Virus by real-time reverse transcriptase PCR.
abstract: An outbreak of highly virulent Chinese-type of Porcine Reproductive and Respiratory Syndrome Virus (H-PRRSV) in most areas of China recently has led to huge economic losses and drawn great attention to its diagnosis and disease control. To facilitate rapid identification of H-PRRSV, a fluorogenic-probe hydrolysis (TaqMan)-reverse transcriptase PCR for H-PRRSV has been developed. Primers and probe specificity were evaluated with RNA extracted from 5 strains of H-PRRSV and 24 strains of other viruses, the results showed 100% specificity for the selected panel. The assay met the sensitivity of 1 50% tissue culture infective dose (TCID50) per ml of samples from infected pigs. Analysis with 10(5)-1TCID50/ml H-PRRSV samples demonstrated high reproducibility with a coefficient of variation (CV) of 0.5-2.5%. More than two hundred samples from lung, spleen, blood serum specimens obtained from 22 outbreaks of suspected H-PRRS from March to June in 2007 were verified using this assay. The results showed that 68.5% (146 out of 213) of these samples were positive which is 100% consistent with that of the sequencing method. The assay can be performed in less than 3h and thus provide a rapid method for the diagnosis of H-PRRSV as well as for elucidation of the epidemiology of H-PRRSV infections.
authors.affiliation: Institution of Food Safety, Department of Food, College of Light Industry & Food, South China University of Technology, Guangzhou 510640, China.
authors.forename: Xing-Long
authors.initials: XL
authors.lastname: Xiao
authors.forename: Hui
authors.initials: H
authors.lastname: Wu
authors.forename: Yi-Gang
authors.initials: YG
authors.lastname: Yu
authors.forename: Bang-Zhao
authors.initials: BZ
authors.lastname: Cheng
authors.forename: Xiao-Quan
authors.initials: XQ
authors.lastname: Yang
authors.forename: Gu
authors.initials: G
authors.lastname: Chen
authors.forename: Dong-Mei
authors.initials: DM
authors.lastname: Liu
authors.forename: Xiao-Feng
authors.initials: XF
authors.lastname: Li
mesh_terms: D000818:Animals; D001483:Base Sequence; D008969:Molecular Sequence Data; D019318:Porcine Reproductive and Respiratory Syndrome / Q000175:diagnosis* / Q000821:virology; D019316:Porcine respiratory and reproductive syndrome virus / Q000235:genetics / Q000302:isolation & purification*; D015203:Reproducibility of Results; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods*; D012680:Sensitivity and Specificity; D013552:Swine / Q000821:virology