Fig 2.

Macroscopic lung lesions on day 5 postinfection were reduced by Ad5-HA vaccination and enhanced in kaCA-vaccinated pigs. Pigs were vaccinated intranasally with Ad5-empty or Ad5-HA 42 days prior to challenge or intramuscularly with kaCA 42 and 21 days prior to challenge. Pigs were challenged intranasally with A/CA/04/09 (CA09), A/SW/MN/2011/08 (MN08), or PBS (NC). The percentage of macroscopic lung lesions in the Ad5-HA- or Ad5-empty-vaccinated pigs (A) and kaCA-vaccinated pigs (B) were evaluated 5 days after infection with the indicated virus. Results are reported as means ± SEM, and statistical differences between nonvaccinated and vaccinated groups challenged with the same virus are indicated with connecting bars and asterisks (P ≤ 0.05).