Fig. 4.
Cross-protective efficacy in mice challenged with lethal doses of H1N1 and H5N1 viruses. BALB/c mice were immunized with three doses of cHAfg and cHAmg with adjuvant Al(OH)3 or C34 at 2-wk intervals. The immunized mice were challenged with H1N1 A/California/07/2009 (A), H1N1 A/New Caledonia/1999 (B), H1N1 A/WSN/1933 (C), H1N1 A/Solomon Islands/03/2006 (D), H5N1 A/Vietnam/1194/2004/NIBRG14 (E), or H5N1 A/Turkey/1/2005/NIBRG23 (F), and the efficacy was evaluated by recording the survival rate for 14 d after infection. **P < 0.01. Significant differences in survival rate were analyzed by log-rank (Mantel–Cox) test.