title: Re-emerging of porcine respiratory and reproductive syndrome virus (lineage 3) and increased pathogenicity after genomic recombination with vaccine variant.
abstract: Porcine reproductive and respiratory syndrome virus (PRRSV) was first reported in China since late 1995 and several variants were further reported in subsequence years, causing huge economic losses to the Chinese swine industry. To date, three major lineages (lineage 3, 5.1 and 8.7) of Type 2 PRRSV were reported in China based on our global genotyping. The present study provides the epidemiology of the PRRSV in South China based on the isolates collected during 2009-2012, indicating three lineages (lineage 3, 5.1 and 8.7) of Type 2 PRRSV were still circulating in this area. Our phylogenetic reconstruction indicated that lineage 3 re-emerged in 2010 formed a huge cluster with closely related to the 2004 isolates from Hong Kong. Furthermore, the inter-lineage genomic recombination between MLV vaccine strain (lineage 5) and a recently re-emerged lineage 3 virus (QYYZ) has also been found in a farm practicing MLV vaccination. Our in vivo experiment comparing the pathogenicity and clinical presentations among currently isolated viruses indicated that pigs infected with recombinant lineage 3 virus (GM2) showed persistent higher fever compared to pigs infected by its wild counterpart (QYYZ). This study enhanced our understanding on potential importance of the recombination of PRRSV along with their evolution.
authors.affiliation: College of Animal Science, South China Agricultural University, Tianhe District, Wushan Road, Guangzhou 510642, Guangdong, PR China.
authors.forename: Wen Hui
authors.initials: WH
authors.lastname: Lu
authors.affiliation: School of Biological Sciences, University of Hong Kong, Pokfulam Road, Hong Kong Special Administrative Region; Department of Animal Science, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada.
authors.forename: Hein Min
authors.initials: HM
authors.lastname: Tun
authors.affiliation: College of Animal Science, South China Agricultural University, Tianhe District, Wushan Road, Guangzhou 510642, Guangdong, PR China.
authors.forename: Bao Li
authors.initials: BL
authors.lastname: Sun
authors.affiliation: College of Animal Science, South China Agricultural University, Tianhe District, Wushan Road, Guangzhou 510642, Guangdong, PR China.
authors.forename: JianYui
authors.initials: J
authors.lastname: Mo
authors.affiliation: Guangdong Wen's Foodstuff Group Co., Ltd., Yanjiang Street, Xinxing 527400, Guangdong, PR China.
authors.forename: Qing Feng
authors.initials: QF
authors.lastname: Zhou
authors.affiliation: College of Animal Science, South China Agricultural University, Tianhe District, Wushan Road, Guangzhou 510642, Guangdong, PR China.
authors.forename: Yu Xiu
authors.initials: YX
authors.lastname: Deng
authors.affiliation: College of Animal Science, South China Agricultural University, Tianhe District, Wushan Road, Guangzhou 510642, Guangdong, PR China.
authors.forename: Qing Mei
authors.initials: QM
authors.lastname: Xie
authors.affiliation: College of Animal Science, South China Agricultural University, Tianhe District, Wushan Road, Guangzhou 510642, Guangdong, PR China.
authors.forename: Ying Zuo
authors.initials: YZ
authors.lastname: Bi
authors.affiliation: School of Biological Sciences, University of Hong Kong, Pokfulam Road, Hong Kong Special Administrative Region.
authors.forename: Frederick Chi-Ching
authors.initials: FC
authors.lastname: Leung
authors.affiliation: College of Animal Science, South China Agricultural University, Tianhe District, Wushan Road, Guangzhou 510642, Guangdong, PR China. Electronic address: majy2400@scau.edu.cn.
authors.forename: Jing Yun
authors.initials: JY
authors.lastname: Ma
mesh_terms: D000818:Animals; D002681:China; D016679:Genome, Viral; D023281:Genomics; D005838:Genotype; D006723:Hong Kong; D010802:Phylogeny; D019318:Porcine Reproductive and Respiratory Syndrome / Q000517:prevention & control / Q000821:virology*; D019316:Porcine respiratory and reproductive syndrome virus / Q000145:classification / Q000235:genetics* / Q000472:pathogenicity; D011995:Recombination, Genetic; D013552:Swine; D014765:Viral Vaccines / Q000276:immunology*; D014774:Virulence
chemical_list: D014765:Viral Vaccines
keywords: PRRSV; Pathogenicity; Recombination; Virulence