Jump to Main Content
Isolation and genetic analysis of a variant porcine epidemic diarrhea virus in China
- Li, Ren-feng, Tian, Xiang-qin, Liu, Yong, Xu, Jing, Liu, Dong-yang
- Polish journal of veterinary sciences 2016 v.19 no.1 pp. 65-73
- Porcine epidemic diarrhea virus, diarrhea, electron microscopy, epidemiology, fluorescent antibody technique, genes, genetic analysis, industry, livestock breeding, mucosa, neonates, phylogeny, piglets, reverse transcriptase polymerase chain reaction, small intestine, vaccines, China
- Porcine epidemic diarrhea virus (PEDV) is having a severe effect on the pig breeding industry in central China. The mucosa and the content of the small intestine from newborn pre-weaned piglets with diarrhea were tested for the presence of PEDV by molecular and morphologic methods, and found to be positive. Negative-staining electron microscopy (EM) revealed the presence of coronavirus- like particles in the samples. The result of molecular detection by nested RT-PCR based on the amplification of the M gene was positive. Using a novel alternative method we successfully propagated the PEDV strain (CH/QX-2) in Vero cells, confirmed by ultrathin sections of the cells and Immunofluorescence assay (IFA). Phylogenetic analysis based on the partial S gene showed that the CH/QX-2 isolate was genetically closer to strains more commonly found in China, but differed genetically from two domestic strains (CH/S, 1986 and LZC, 2007), Korean strains (DR13, 2007), and the vaccine strain (CV777 vs) currently being used in China. CH/QX-2 formed a unique clade in the derived phylogenetic tree indicating that the CH/QX-2 strain currently circulating in central China is a new variant of PEDV. This study extends current knowledge on the diversity and epidemiology of PEDV.