DBA/2 and BALB/c challenge models for H1N1.
Wild-type CA07 (102, 103 PFU) and CodaVax-H1N1 (106 PFU) were used to infect DBA/2 (A) and CA07ma used to infect BALB/c (B) mice by the intranasal route in a volume of 25 μl. In DBA/2 mice, the LD50 of wild-type CA07 was 3.2 x 102 PFU while the LD50 of CodaVax-H1N1 was ≥3.2 x 106 PFU, at least a 10,000-fold difference. CA07ma had an LD50 of 4.2 x 102 PFU while neither CA07 WT nor CodaVax-H1N1 caused morbidity or mortality in BALB/c mice. DPI: Days Post Infection.