FIG. 1.
Replication in BALB/c mice of recombinant wt HRSV and the gene deletion viruses lacking NS1 and/or NS2. Groups of mice (five animals per virus per day) were inoculated intranasally with 106 PFU of the indicated viruses and sacrificed on days 4 and 5. Titers of the viruses in nasal turbinates and lungs were determined by plaque assay of the tissue homogenates and are shown as means ± SE. The data shown are from a representative experiment from a total of three independent experiments. Significant differences and corresponding P values are indicated above the graphs.