Walters, M.

virus zanamivir influenza susceptibility assay reduction influenza virus plaque control study treatment change subject titer plaque reduction table mdck cells neuraminidase infection placebo group enzyme mutation animal inhibitor ic 50s nasal-wash plaque reduction assay activity virus titers value 0.01 efficacy naib 2008 result culture agents chemother variant temperature plaque reduction assays sequence resistance zanamivir susceptibility monitoring therapy model primers 100 g /ml influenza viruses concentration sample acid changes /beijing 5 days day 2 inhibition kingdom 0.01 mg /kg analysis agent addition range virology sequencing 3 days response placebo group 0.14 0.1 0.05 0.04 0.9 residue day 1 bethell naib 2005 baseline strain 1.5 wild-type b /beijing