Update: Brutal Flu Outbreak Has Finally Peaked

January 16th, 2018

By Gary Evans, Medical Writer

The severe 2017-18 flu season has peaked and cases are gradually declining, but influenza activity still remains high over much of the U.S., the Centers for Disease Control and Prevention reports.

In data reported as of Feb. 24, the CDC said the hospitalization rate was similar to 2014-15, another high severity season with H3N2 influenza A, the predominant circulating strain. The efficacy of the flu vaccine against H3N2 is only 25% this year, although that is still better than the 10% and 17% effectiveness estimates respectively reported by Australia and Canada.

The vaccine has a 67% efficacy against the H1N1 A strain and is 42% effective against influenza B viruses, the CDC reported. Although these higher vaccine efficacy levels certainly help, the problem is that 69% of reported cases have been caused by H3N2.

The CDC continues to recommend influenza vaccination for all people 6 months of age and older, as flu will likely continue circulating for weeks. As of this report, 114 children have died this season of causes related to flu. The CDC has previously estimated that this flu season may see an overall death toll of 50,000 people when mortality for all age groups is calculated.

For more on this story see the April 2018 issue of Hospital Employee Health.