FIG 6.
Morbidity and mortality in mice after heterologous challenge. Mice were immunized with NL/219 (A) and CA/07-like (B) whole inactivated vaccine. On day 63 postpriming (day 42 postboost), mice were cross-challenged with 105 PFU of wild-type CA/07/2009 (A) or 8 × 102 PFU of NL/219 (B) virus. Mice were observed daily for morbidity and mortality for 14 days. The left graphs show the group mean weights ± SEM as a percentage of the day 0 weight. Daily statistical significance was calculated by multiple t tests. The right graphs show percent survival. Statistical significance between survival curves were calculated using the log rank (Mantel-Cox) test (P values are shown).