FIG 12.
Efficient respiratory droplet transmission of P9 virus-derived L2 virus in ferrets. Three ferrets were intranasally inoculated with 106 TCID50 of L2 (A), N9 (B), L18 (C), or parental rHIN1 (D) virus. Each infected animal was individually housed next to a naive ferret in an adjacent cage (5 cm away). Virus titers of nasal washes were determined by TCID50 assays on MDCK cells and plotted as directly infected and proximally exposed groups of animals against the number of days after virus inoculation. The horizontal dashed line represents the detection limit of the TCID50 assay. Each bar represents the virus titer from an individual animal. The asterisk indicates a ferret that died at 7 dpi.