Influenza cases breach baseline threshold for first time this season

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  • Influenza-like illness (ILI) exceeded the national baseline level for the first time this influenza season, increasing to 2.3% during the week of December 17.

Why this matters

  • This season’s trivalent and quadrivalent influenza vaccine formulations are well-matched to almost all currently circulating influenza viruses, which are also sensitive to the antivirals oseltamivir, zanamivir, and peramivir.

Study design

  • US Centers for Disease Control and Prevention (CDC) Morbidity and Mortality Weekly Report (MMWR) update on influenza activity from October to mid-December 2016.

Key results

  • After a steady increase in activity during November and early December, outpatient visits for ILI exceeded the national baseline...