Volume 18, Number 12—December 2012
Research
Subclinical Influenza Virus A Infections in Pigs Exhibited at Agricultural Fairs, Ohio, USA, 2009–2011
Table 1
Clinical signs of ILI and influenza virus A recovery from pigs at agricultural fairs, Ohio, USA, 2009–2011*
Year | No. participating fairs | No. fairs with pigs with ILI | No. (%) fairs with >1 pig testing positive for influenza virus A | No. (%) fairs with subclinical influenza virus A infection in pigs |
---|---|---|---|---|
2009 | 15 | 0 | 3 (20.0) | 3 (20.0) |
2010 | 16 | 1 | 3 (18.8) | 2 (12.5) |
2011 | 22 | 1 | 6 (27.3) | 5 (22.7) |
*Influenza A virus was recovered from pigs at both fairs where there were pigs with ILI. ILI, influenza-like illness.