FIG 2.

Virulence of QT1728 and QT1480 viruses in BALB/c mice. (A to D) Three or four mice per group were inoculated intranasally with the indicated doses of QT1728 or QT1480 virus and monitored for survival (A and B) and weight changes (C and D) for 14 days. The results shown are mean values ± standard deviations (error bars) from three or four individual mice. (E and F) To assess virus titers in mouse organs, six mice per group were inoculated intranasally with 10³ PFU of virus. Three mice per group were euthanized on day 3 and day 6 postinfection, respectively, and lungs, nasal turbinates, brains, spleens, and kidneys were collected for virus titration in MDCK cells. Each symbol represents the value for an individual mouse. The data shown are mean values (long horizontal lines) plus standard deviations (SD) (short horizontal lines).