FIG. 6.
rHPIV1-P(C−) is attenuated for replication in both the URT and LRT of AGMs. Groups of AGMs were inoculated i.n. and i.t. with 106 TCID50 of wt HPIV1 (n = 16) or rHPIV1-P(C−) (n = 4) per site. Previously published data for rHPIV1-CF170S (n = 4) are also included for comparison (2). Mean daily virus titers ± SE in NP swabs (representative of the URT) (A) and TL fluid (representative of the LRT) (B) were determined for each sampling day (see Materials and Methods; the limit of detection is 0.5 log10 TCID50/ml). The area shaded in gray represents the additional reduction in replication observed for rHPIV1-P(C−) compared to that of rHPIV1-CF170S.