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.