FIG. 1.
Pathogenicity of the parental H1N1pdm virus (rNY1682-WT) and the mouse-adapted variant (NY1682-MAP7) in mice. Six-week-old female BALB/cJ mice (n = 5/group) were inoculated intranasally with 50 μl containing 104 or 105 TCID50 of rNY1682-WT (WT) or NY1682-MAP7 (MAP7) viruses or mock inoculated (Mock; n = 4). (A) Morbidity was examined by recording the body weights of inoculated mice daily, and it is represented as a percentage of the weight on the day of inoculation (day 0). The average of each group is shown, and the error bars represent the standard deviations from the mean (SD). *, F tests indicated that MAP7 caused greater weight loss than the WT (P < 10−13). (B) Mouse mortality after inoculation with 50 μl containing 104 or 105 TCID50 of rNY1682-WT (WT) or NY1682-MAP7 (MAP7) or diluent (Mock).