FIG 1.

Effect of NAI treatment on replication kinetics of recombinant B/Yamanashi/166/1998 influenza viruses in NHBE cells. (A and B) Multicycle growth curves after infection of NHBE cells with recombinant B/Yamanashi/166/1998 influenza virus at an MOI of 0.01 PFU/cell grown either without drug pressure (A and B), with 10 μM oseltamivir (A), or with 10 μM zanamivir (B). Virus yield in MDCK cells was determined by the TCID₅₀ assay at 33°C and expressed as log₁₀ TCID₅₀/ml. Each data point represents the mean ± SD from two independent experiments. The limit of detection was 0.75 log₁₀ TCID₅₀/ml. *, P < 0.05; **, P < 0.01; †, P < 0.001; ‡, P < 0.0001. Abbreviations: OSE, oseltamivir; ZAN, zanamivir.