title: Subclinical influenza virus A infections in pigs exhibited at agricultural fairs, Ohio, USA, 2009-2011.
abstract: Agricultural fairs are associated with bidirectional, interspecies transmission of influenza virus A between humans and pigs. We examined pigs exhibited at agricultural fairs in Ohio during 2009-2011 for signs of influenza-like illness and collected nasal swab specimens from a representative subset of these animals. Influenza virus A was recovered from pigs at 12/53 (22.6%) fairs during the 3-year sampling period. Pigs at 10/12 (83.3%) fairs from which influenza virus A was recovered did not show signs of influenza-like illness. Hemagglutinin, neuraminidase, and matrix gene combinations of the isolates were consistent with influenza virus A concurrently circulating among swine herds in the United States. Subclinical influenza virus A infections in pigs at agricultural fairs may pose a risk to human health and create challenges for passive surveillance programs for influenza virus A in swine herds.
authors.affiliation: The Ohio State University, Department of Veterinary Preventive Medicine, Columbus, Ohio, USA. bowman.214@osu.edu
authors.forename: Andrew S
authors.initials: AS
authors.lastname: Bowman
authors.forename: Jacqueline M
authors.initials: JM
authors.lastname: Nolting
authors.forename: Sarah W
authors.initials: SW
authors.lastname: Nelson
authors.forename: Richard D
authors.initials: RD
authors.lastname: Slemons
mesh_terms: D000818:Animals; D002460:Cell Line; D019267:Hemagglutinin Glycoproteins, Influenza Virus / Q000235:genetics; D009980:Influenza A virus / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D009439:Neuraminidase / Q000235:genetics; D009820:Ohio / Q000453:epidemiology; D009976:Orthomyxoviridae Infections / Q000662:veterinary* / Q000821:virology; D012703:Serotyping; D013552:Swine; D013553:Swine Diseases / Q000453:epidemiology / Q000821:virology*; D014763:Viral Matrix Proteins / Q000235:genetics
chemical_list: D019267:Hemagglutinin Glycoproteins, Influenza Virus; C488936:M1 protein, Influenza A virus; D014763:Viral Matrix Proteins; D009439:Neuraminidase