FIG 4.
Survival rates of BALB/c mice challenged intranasally with H5N1 virus A/VNM/1194/2004. Mice received imiquimod (50 μg) and PANENZA vaccine (3 μg of HA) in combination (■) (VCI day −3), imiquimod (50 μg) and formalin-inactivated A/VNM/1194/2004 vaccine (3 μg of HA) in combination (●) (VH5CI day −3), or PBS (⧫) on day −3 before virus infection. On the day of infection, mice were inoculated intranasally with 5 times the mouse LD50 of A/VNM/1194/2004 diluted in 20 μl of PBS. Survival was observed for 14 days after virus infection. **, P < 0.01 (compared with the imiquimod-PANENZA vaccine [VCI day −3] or PBS group). n = 6 per group.