Article Title: CDC: Flu shot less effective this year because current virus has mutated
Snippet of Article: "...Centers for Disease Control and Prevention said Thursday, a day after the agency advised doctors this year's flu vaccine is not as effective because the current strain of the virus has mutated.
Dr. Tom Frieden said researchers are worried that with this particular strain of the virus, "we could have a season that is more severe than most with more hospitalizations and more deaths."..."
Source: www.cnn.com