ARS | Publication request: Simultaneous infection of pigs and people with triple reassortant swine influenza virus H1N1 at a U.S. county fair

Submitted to: Zoonoses and Public Health
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: May 3, 2012
Publication Date: May 1, 2013
Repository URL: http://handle.nal.usda.gov/10113/56419
Citation: Killian, M.L., Swenson, S.L., Vincent, A.L., Landgraf, J.G., Shu, B., Lindstrom, S., Xu, X., Klimov, A., Zhang, Y., Bowman, A.S. 2013. Simultaneous infection of pigs and people with triple-reassortant swine influenza virus H1N1 at a U.S. county fair. Zoonoses and Public Health. 60(3):196-201.

Interpretive Summary: Swine influenza virus (SIV) is one of the primary causes of respiratory disease in growing pigs and can lead to major economic losses. There is a potential for people exposed to SIV to become infected, although this event is far less common than the spread of human influenza virus from person to person. In this paper, we studied a virus from pigs that also infected 2 people during attendance at an Ohio county fair in August 2007. The number of ill swine at the fair approached 100 percent within 1 to 2 days of initial symptoms being recognized and approximately 2 dozen people in contact with the pigs developed influenza-like illness. Identical triple reassortant swine H1N1 influenza viruses were identified in both the affected pigs and people at the fair. The identified viruses (A/Sw/OH/511445/2007, A/Ohio/01/2007, and A/Ohio/02/2007) were similar to H1N1 swine influenza viruses found in the U.S. swine population at that time. The recognition and investigation of these sporadic events are essential to gain a better understanding of the factors that allow swine-adapted influenza viruses to infect people.

Technical Abstract: Influenza-like illness was noted in people and pigs in attendance at an Ohio county fair in August 2007. The morbidity rate in swine approached 100 percent within one to two days of initial symptoms being recognized and approximately two dozen people developed influenza-like illness. Triple reassortant swine H1N1 influenza viruses were identified in both pigs and people at the fair. The identified viruses (A/Sw/OH/511445/2007, A/Ohio/01/2007, and A/Ohio/02/2007) were similar to H1N1 swine influenza viruses currently found in the U.S. swine population.