Attenuation of mutant viruses in mice.

<p>Seven to eight mice per group were intranasally infected with each virus and their morbidity and mortality were monitored daily for two weeks. (A–F) Time-course changes of body weights (left) and survival rates (right) of mice infected with various doses of WT virus (n = 8) (A), NP-C (n = 8) (B), NS1-C (n = 7) (C), DM-C (n = 8) (D), NP-DEVA (n = 8) (E), or NS1-DEVA (n = 8) (F). Data are the means of each cohort, and error bars indicate SD.