Neuraminidase inhibitor susceptibility testing of influenza type B viruses in China during 2010 and 2011 identifies viruses with reduced susceptibility to oseltamivir and zanamivir

► We report the drug resistance in country with low or non-existing NAI use. ► Influenza B viruses with reduced susceptibility to NAIs were identified. ► I222T and D197N mutation in NA gene was identified in China for the first time.