title: Genetic diversity of swine influenza viruses in Thai swine farms, 2011-2014.
abstract: The pig is known as a "mixing vessel" for influenza A viruses. The co-circulation of multiple influenza A subtypes in pig populations can lead to novel reassortant strains. For this study, swine influenza surveillance was conducted from September 2011 to February 2014 on 46 swine farms in Thailand. In total, 78 swine influenza viruses were isolated from 2,821 nasal swabs, and 12 were selected for characterization by whole genome sequencing. Our results showed that the co-circulation of swine influenza subtypes H1N1, H3N2, and H1N2 in Thai swine farms was observable throughout the 3 years of surveillance. Furthermore, we repeatedly found reassortant viruses between endemic swine influenza viruses and pandemic H1N1 2009. This observation suggests that there is significant and rapid evolution of swine influenza viruses in swine. Thus, continuous surveillance is critical for monitoring novel reassortant influenza A viruses in Thai swine populations.
authors.affiliation: Faculty of Veterinary Science, Center of Excellence for Emerging and Re-emerging Infectious Diseases in Animals, Chulalongkorn University, Bangkok, Thailand, nnutthawan@hotmail.com.
authors.forename: Nutthawan
authors.initials: N
authors.lastname: Nonthabenjawan
authors.forename: Sunicha
authors.initials: S
authors.lastname: Chanvatik
authors.forename: Supassama
authors.initials: S
authors.lastname: Chaiyawong
authors.forename: Waleemas
authors.initials: W
authors.lastname: Jairak
authors.forename: Supanat
authors.initials: S
authors.lastname: Boonyapisusopha
authors.forename: Ranida
authors.initials: R
authors.lastname: Tuanudom
authors.forename: Aunyaratana
authors.initials: A
authors.lastname: Thontiravong
authors.forename: Napawan
authors.initials: N
authors.lastname: Bunpapong
authors.forename: Alongkorn
authors.initials: A
authors.lastname: Amonsin
mesh_terms: D000822:Animal Husbandry; D000818:Animals; D019143:Evolution, Molecular; D005260:Female; D014644:Genetic Variation; D053118:Influenza A Virus, H1N1 Subtype / Q000145:classification / Q000235:genetics / Q000302:isolation & purification; D057221:Influenza A Virus, H1N2 Subtype / Q000145:classification / Q000235:genetics / Q000302:isolation & purification; D053122:Influenza A Virus, H3N2 Subtype / Q000145:classification / Q000235:genetics / Q000302:isolation & purification; D009980:Influenza A virus / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification*; D008297:Male; D008969:Molecular Sequence Data; D009976:Orthomyxoviridae Infections / Q000453:epidemiology / Q000662:veterinary* / Q000821:virology; D010802:Phylogeny; D016865:Reassortant Viruses / Q000145:classification / Q000235:genetics / Q000302:isolation & purification; D013552:Swine; D013553:Swine Diseases / Q000453:epidemiology / Q000821:virology*; D013785:Thailand / Q000453:epidemiology