Molecular epidemiology of porcine epidemic diarrhea virus in China
- 1.5k Downloads
Since early 2006, porcine epidemic diarrhea virus (PEDV) has been reemerging in immunized swine herds. Open reading frame 3 (ORF3) is the only accessory gene in the PEDV genome. The entire ORF3 genes of 12 PEDV field strains and one vaccine strain were sequenced. The ORF3 genes of Chinese PEDV field strains (excluding CH/GSJIII/07) contain a single 672- or 675-nucleotide (nt) ORF, which encodes a 223- or 224-aa-long peptide. However, the CV777 vaccine strain and CH/GSJIII/07 contain a 276-nt ORF because of a 49-nt deletion at nt 245–293. The Chinese PEDV field strains and PEDV reference strains are divided into three groups based on the phylogenetic relationship of their ORF3 genes. Chinese PEDV field strains (excluding CH/GSJIII/07) have a close phylogenetic relationship to Korean strains and are genetically different from the PEDV vaccine strains. However, CH/GSJIII/07 has a close phylogenetic relationship to two vaccine strains, suggesting that it might have evolved from a live vaccine strain. Chinese PEDV field strains (excluding CH/GSJIII/07) can be differentiated from PEDV vaccine strains by a nested RT-PCR method.
KeywordsPorcine epidemic diarrhea virus The phylogenetic relationship ORF3 New genotype Nested RT-PCR
This study was supported by National Key Laboratory of Veterinary Biotechnology (NKLVBP200805), National Natural Science Foundation of China (30901081), and National Key Technology Research and Development Program (2006BAD06A07). We also thank Dr. Tongqing An for providing ClustalX v1.83 and MEGA 4 softwares and giving advice.
- 2.Pensaert MB, Yeo SG (2006) Porcine epidemic diarrhea. In: Straw BE, Zimmerman JJ, D’Allaire S, Taylor DJ (eds) Disease of Swine, 9th edn. Blackwell, Ames, pp 367–372Google Scholar
- 3.Xuan H, Xing D, Wang D, Zhu W, Zhao F, Gong H (1984) Study on the culture of porcine epidemic diarrhea virus adapted to fetal porcine intestine primary cell monolayer. Chin J Vet Sci 4(3):202–208Google Scholar
- 4.Ma S, Wang M, Feng L, Li W (1995) Study on Bi-combined killed vaccine transmissible gastroenteritis virus and porcine epidemic diarrhea virus. Chin J Prev Vet Med 17(6):23–27Google Scholar
- 5.Tong Y, Feng L, Li W, Zhu Y, Wang M, Ma S (1999) Development of Bi-combined attenuated vaccine against transmissible gastroenteritis virus and porcine epidemic diarrhea virus. Chin J Prev Vet Med 21(6):406–410Google Scholar
- 17.Song DS, Oh JS, Kang BK, Yang JS, Song JY, Moon HJ, Kim TY, Yoo HS, Jang YS, Park BK (2005) Fecal shedding of a highly cell adapted porcine epidemic diarrhea virus after oral inoculation in pigs. J Swine Health Prod 13(5):269–272Google Scholar