‘Severe’ Flu Season Could Grip US, CDC Doc Warns

A deadly influenza strain has the U.S. in the grip of what could develop into a “severe” flu season, with widespread cases already reported in 36 states, a Centers for Disease Control and Prevention expert said Tuesday.

The H3N2 strain, the most common flu virus this season, began mutating shortly after U.S. health experts created this year’s vaccine — rendering it less effective compared to past flu vaccines, Dr. Michael Jhung, a medical officer with the CDC’s influenza division, told FoxNews.com.

The H3N2 virus was predominant during the 2012-13, 2007-08 and 2003-04 flu seasons, the CDC said earlier this month. Because it’s been associated with particularly harsh flu seasons in the past, the CDC believes the 2014-15 season could be a “severe” one, Jhung said.

But he cautioned that this year’s flu season — which began in late November and is expected to continue through April — won’t be “terribly severe.”