In February 2016, three influenza B/Victoria/2/87 lineage viruses exhibiting 4- to 158-fold reduced inhibition by neuraminidase inhibitors were detected in Laos. These viruses had an H134N substitution in the neuraminidase and replicated efficiently in vitro and in ferrets. Current antiviral drugs may be ineffective in controlling infections caused by viruses harboring this mutation.
Keywords: H134N substitution; Laos; antimicrobial resistance; antiviral drug–resistant; influenza; influenza B viruses; mutation; neuraminidase; viruses.