CDC: Flu Strain Doesn’t Match This Year’s Vaccine

Federal health officials are warning that this year’s flu vaccine will do little to stop about half of influenza cases in the United States.

The Centers for Disease Control and Prevention (CDC) alerted doctors Wednesday night that the predominant strain of flu this year — H3N2 — has mutated substantially enough not to match the vaccine.

While the shot protects against three of four strains of influenza, including H3N2, roughly half of cases are now caused by mutations that don’t match the treatment, according to NBC News.