CDC: 2017/2018 flu season strongest since 2009

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CDC: 2017/2018 flu season strongest since 2009

By Michael Johnsen - 01/05/2018

Steel yourself for a strong cough/cold and flu season. Because before the ball even had a chance to drop in Times Square on Dec. 31, the 2017/2018 flu season is already being touted as the strongest on record since the 2009 H1N1 pandemic. According to data released by the Centers for Disease Control and Prevention on Friday, 5.8% of patient visits reported through the U.S. Outpatient Influenza-like Illness Surveillance Network were due to influenza-like illness.



That is well above the peak of illness rates recorded for the 2016/2017 season and nearly matches the height of illness rates recorded across the 2014/2015 season. And all indications suggest we haven't seen the peak of this year's season, yet.



According to the CDC, 46 states reported widespread influenza activity. The most frequently identified influenza virus subtype reported by public health laboratories during the week was influenza A(H3N2). In the past, A(H3N2) virus-predominant influenza seasons have been associated with more hospitalizations and deaths in persons aged 65 years and older and young children compared to other age groups. In addition, influenza vaccine effectiveness in general has been lower against A(H3N2) viruses than against influenza A(H1N1) or influenza B viruses.



Last season, vaccine effectiveness against circulating influenza A(H3N2) viruses was estimated to be 32% in the U.S.  CDC expects that VE could be similar this season, should the same A(H3N2) viruses continue to predominate. For this reason, in addition to influenza vaccination for prevention of influenza, the use of antiviral medications for treatment of influenza becomes even more important than usual.