Figure 2.

Average virus titers in lungs (A, B) at 5 days post‐infection (dpi) and nasal swabs (C, D) at 1, 3, and 5 dpi from C, MDA/C, MDA/V/C, and V/C pigs from trial 1 (A and C) and from C, WIV/C, and LAIV/C in trial 2 (B and D) as mean log₁₀ TCID₅₀/ml ± SEM. Different superscript letters or * within the figure are significant difference between the values (P ≤ 0·05). Virus was not isolated from any non‐challenged pigs, and results are not included. C, challenged; MDA, maternal derived antibody; V, vaccinated; WIV, whole virus inactivated vaccine; and LAIV, live attenuated influenza vaccine.