title: The repeated introduction of the H3N2 virus from human to swine during 1979-1993 in China.
abstract: Limited data are available regarding the swine influenza viruses (SIVs) that circulated in Mainland China prior to the 1990s. Eleven H3N2 virus strains were isolated from swine populations from 1979 to 1992. To determine the origin and tendency of these SIVs, the phylogenetic and antigenic properties of these viruses were analyzed based on the whole genome sequenced and the HI titrations with post-infection ferret antisera against influenza A (H3N2) virus isolates of swine and human origin. The results revealed that these 11 SIVs originated from humans and were not maintained in swine populations, indicating the interspecies transmission from humans to pigs occurred frequently and independently throughout these periods. However, human H3N2 viruses might not have the ability to circulate in pig herds.
authors: Chinese National Influenza Center, National Institute for Viral Disease Control and Prevention, Key Laboratory of Surveillance and Early-warning on Infectious Disease, China CDC, Key Laboratory for Medical Virology, National Health and Family Planning Commission, 155 Changbai Road, Beijing 102206, PR China.
authors: Wenfei
authors: W
authors: Zhu
authors: Chinese National Influenza Center, National Institute for Viral Disease Control and Prevention, Key Laboratory of Surveillance and Early-warning on Infectious Disease, China CDC, Key Laboratory for Medical Virology, National Health and Family Planning Commission, 155 Changbai Road, Beijing 102206, PR China.
authors: Shuai
authors: S
authors: Yang
authors: Chinese National Influenza Center, National Institute for Viral Disease Control and Prevention, Key Laboratory of Surveillance and Early-warning on Infectious Disease, China CDC, Key Laboratory for Medical Virology, National Health and Family Planning Commission, 155 Changbai Road, Beijing 102206, PR China.
authors: Libo
authors: L
authors: Dong
authors: Chinese National Influenza Center, National Institute for Viral Disease Control and Prevention, Key Laboratory of Surveillance and Early-warning on Infectious Disease, China CDC, Key Laboratory for Medical Virology, National Health and Family Planning Commission, 155 Changbai Road, Beijing 102206, PR China.
authors: Lei
authors: L
authors: Yang
authors: Chinese National Influenza Center, National Institute for Viral Disease Control and Prevention, Key Laboratory of Surveillance and Early-warning on Infectious Disease, China CDC, Key Laboratory for Medical Virology, National Health and Family Planning Commission, 155 Changbai Road, Beijing 102206, PR China.
authors: Jing
authors: J
authors: Tang
authors: Chinese National Influenza Center, National Institute for Viral Disease Control and Prevention, Key Laboratory of Surveillance and Early-warning on Infectious Disease, China CDC, Key Laboratory for Medical Virology, National Health and Family Planning Commission, 155 Changbai Road, Beijing 102206, PR China.
authors: Xiaohui
authors: X
authors: Zou
authors: Chinese National Influenza Center, National Institute for Viral Disease Control and Prevention, Key Laboratory of Surveillance and Early-warning on Infectious Disease, China CDC, Key Laboratory for Medical Virology, National Health and Family Planning Commission, 155 Changbai Road, Beijing 102206, PR China.
authors: Tao
authors: T
authors: Chen
authors: Chinese National Influenza Center, National Institute for Viral Disease Control and Prevention, Key Laboratory of Surveillance and Early-warning on Infectious Disease, China CDC, Key Laboratory for Medical Virology, National Health and Family Planning Commission, 155 Changbai Road, Beijing 102206, PR China.
authors: Jing
authors: J
authors: Yang
authors: Chinese National Influenza Center, National Institute for Viral Disease Control and Prevention, Key Laboratory of Surveillance and Early-warning on Infectious Disease, China CDC, Key Laboratory for Medical Virology, National Health and Family Planning Commission, 155 Changbai Road, Beijing 102206, PR China. Electronic address: yshu@cnic.org.cn.
authors: Yuelong
authors: Y
authors: Shu
mesh_terms: D000818:Animals; D000956:Antigens, Viral / Q000276:immunology; D002681:China / Q000453:epidemiology; D049673:History, 20th Century; D049674:History, 21st Century; D006801:Humans; D053122:Influenza A Virus, H3N2 Subtype / Q000145:classification* / Q000235:genetics / Q000276:immunology; D007251:Influenza, Human / Q000453:epidemiology* / Q000266:history / Q000821:virology*; D009976:Orthomyxoviridae Infections / Q000662:veterinary*; D010802:Phylogeny; D012367:RNA, Viral; D017422:Sequence Analysis, DNA; D013552:Swine; D013553:Swine Diseases / Q000453:epidemiology* / Q000266:history / Q000635:transmission / Q000821:virology*
chemical_list: D000956:Antigens, Viral; D012367:RNA, Viral
keywords: Genetic analysis; Human H3N2 in swine; Influenza viruses