Human-to-Human Transmission of Influenza A(H3N2) Virus With Reduced Susceptibility to Baloxavir, Japan, February 2019

Emerg Infect Dis. 2019 Nov;25(11):2108-2111. doi: 10.3201/eid2511.190757. Epub 2019 Nov 17.

Abstract

In 2019, influenza A(H3N2) viruses carrying an I38T substitution in the polymerase acidic gene, which confers reduced susceptibility to baloxavir, were detected in Japan in an infant without baloxavir exposure and a baloxavir-treated sibling. These viruses' whole-genome sequences were identical, indicating human-to-human transmission. Influenza virus isolates should be monitored for baloxavir susceptibility.

Keywords: H3N2; I38T substitution; Japan; antimicrobial resistance; baloxavir; baloxavir acid; baloxavir marboxil; cap-dependent endonuclease inhibitor; family cluster; human-to-human transmission; influenza; influenza A(H1N1)pdm09; influenza virus; polymerase acidic; respiratory infections; viruses; whole-genome sequencing.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Antiviral Agents / pharmacology*
  • Antiviral Agents / therapeutic use
  • Child
  • Disease Susceptibility*
  • Humans
  • Infant
  • Influenza A Virus, H3N2 Subtype / drug effects*
  • Influenza A Virus, H3N2 Subtype / genetics
  • Influenza, Human / drug therapy
  • Influenza, Human / epidemiology
  • Influenza, Human / transmission*
  • Influenza, Human / virology*
  • Japan / epidemiology
  • Middle Aged
  • Mutation
  • Oxazines / pharmacology*
  • Oxazines / therapeutic use
  • Pyridines / pharmacology*
  • Pyridines / therapeutic use
  • Thiepins / pharmacology*
  • Thiepins / therapeutic use
  • Triazines / pharmacology*
  • Triazines / therapeutic use
  • Young Adult

Substances

  • Antiviral Agents
  • Oxazines
  • Pyridines
  • Thiepins
  • Triazines
  • baloxavir