title: Molecular characterization and phylogenetic analysis of porcine epidemic diarrhea viruses associated with outbreaks of severe diarrhea in piglets in Jiangxi, China 2013.
abstract: Porcine epidemic diarrhea (PED), caused by porcine epidemic diarrhea virus (PEDV), is a highly contagious, acute enteric viral disease of swine characterized by vomiting, watery diarrhea, dehydration and death. To identify and characterize the field PEDVs associated with the outbreaks of severe diarrhea in piglets in Jiangxi, 2013, the complete genome sequences of two representative strains of PEDV, designated CH/JX-1/2013 and CH/JX-2/2013, were determined and analyzed. The genome sequences of both emergent Jiangxi PEDV strains, CH/JX-1/2013 and CH/JX-2/2013, were 28,038 nucleotides in length excluding 3' poly (A) tail. Compared to the PEDV CV777 strain, CH/JX-1/2013 and CH/JX-2/2013 had some unique genetic characteristics in the proximal region of the 5´-UTRs. Phylogenetic analysis of the complete genomes and the structural proteins revealed that CH/JX-1/2013 and CH/JX-2/2013 had a close relationship with post-2010 Chinese PEDV strains and US strains identified in 2013. The nucleotide identity between the two Jiangxi strains (CH/JX-1/2013 and CH/JX-2/2013) and 30 strains of PEDV identified ante-2010 and post-2010 ranged from 96.3-97.0% and 97.3-99.7%, respectively. Multiple nucleotide and deduced amino acid mutations were observed in the ORF1a/b, S, ORF3, E, M and N genes among the current field PEDV strains when compared to the CV777 strain. Some of the mutations altered the amino acid charge and hydrophilicity, and notably, there was an amino acid substitution in the middle of one neutralizing epitope (L1371I) of the S gene of both CH/JX-1/2013 and CH/JX-2/2013. Taken together, the accumulated genetic variations of the current field PEDV strains might have led to antigenic changes of the viruses, which might confer the less effectiveness or failure of the CV777-based vaccines currently being widely used in Jiangxi, China.
authors: Department of Preventive Veterinary Medicine, College of Animal Science and Technology, Jiangxi Agricultural University, Nanchang, Jiangxi, China.
authors: Deping
authors: D
authors: Song
authors: Department of Preventive Veterinary Medicine, College of Animal Science and Technology, Jiangxi Agricultural University, Nanchang, Jiangxi, China.
authors: Dongyan
authors: D
authors: Huang
authors: Department of Preventive Veterinary Medicine, College of Animal Science and Technology, Jiangxi Agricultural University, Nanchang, Jiangxi, China.
authors: Qi
authors: Q
authors: Peng
authors: Department of Preventive Veterinary Medicine, College of Animal Science and Technology, Jiangxi Agricultural University, Nanchang, Jiangxi, China.
authors: Tao
authors: T
authors: Huang
authors: Department of Preventive Veterinary Medicine, College of Animal Science and Technology, Jiangxi Agricultural University, Nanchang, Jiangxi, China.
authors: Yanjun
authors: Y
authors: Chen
authors: Department of Preventive Veterinary Medicine, College of Animal Science and Technology, Jiangxi Agricultural University, Nanchang, Jiangxi, China.
authors: Tiansheng
authors: T
authors: Zhang
authors: Department of Preventive Veterinary Medicine, College of Animal Science and Technology, Jiangxi Agricultural University, Nanchang, Jiangxi, China.
authors: Xiaowei
authors: X
authors: Nie
authors: Department of Preventive Veterinary Medicine, College of Animal Science and Technology, Jiangxi Agricultural University, Nanchang, Jiangxi, China.
authors: Houjun
authors: H
authors: He
authors: Department of Preventive Veterinary Medicine, College of Animal Science and Technology, Jiangxi Agricultural University, Nanchang, Jiangxi, China.
authors: Ping
authors: P
authors: Wang
authors: Jiangxi Academy of Agricultural Sciences, Nanchang, Jiangxi, China.
authors: Qinglan
authors: Q
authors: Liu
authors: Department of Preventive Veterinary Medicine, College of Animal Science and Technology, Jiangxi Agricultural University, Nanchang, Jiangxi, China.
authors: Yuxin
authors: Y
authors: Tang
mesh_terms: D000818:Animals; D002681:China / Q000453:epidemiology; D018352:Coronavirus Infections / Q000662:veterinary* / Q000821:virology; D003967:Diarrhea / Q000453:epidemiology / Q000662:veterinary* / Q000821:virology; D004196:Disease Outbreaks; D016679:Genome, Viral; D009154:Mutation; D010802:Phylogeny; D053485:Porcine epidemic diarrhea virus / Q000145:classification / Q000235:genetics*; D017423:Sequence Analysis, RNA; D013552:Swine; D013553:Swine Diseases / Q000453:epidemiology / Q000821:virology*