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7 Things You Don’t Know About Flu


We are in the midst of the worst flu season in 10 years, with almost every state in the union reporting widespread outbreaks. Yet with all the headlines about this year’s super-flu, some misconceptions remain. We talked to three experts to sort flu fact from fiction.

1. The flu vaccine will not give you flu

The flu shot does not contain live viruses, so it’s impossible for you to get sick from them, says microbiologist Ted Myatt, Ph.D., senior scientist at the consulting firm Environmental Health and Engineering and director of research compliance at University of Rhode Island. “Although the nasal-spray version of the vaccine does contain the live virus, it’s manipulated so you get the immune reaction you’re looking for but the virus is not strong enough to make you sick,” says Myatt. 

2. The flu shot does not always work right away

One reason people might believe they’ve gotten sick from a flu shot is that it takes up to two weeks for it to be effective, plenty of opportunity for you to contract a bug in the meantime. “Your body needs time to mount an immune response to the vaccine, and it takes a while to get the highest level of protection,” says Jennifer Trachtenberg, M.D., a pediatrician at The Mount Sinai Medical Center in New York and Fellow of the American Academy of Pediatrics.

3. You can still get the flu, even if you’ve gotten a flu shot

Each year, many months before the start of flu season, experts choose the three strains that will comprise the following year’s flu shot. “It’s their best guess; they don’t know for sure what strains will hit the population,” according to Myatt. So even with a flu shot, you could still contract a strain that wasn’t in this year’s batch. Also, the flu shot is only 60 to 75 percent effective. Still, “it drastically lowers your chances of getting the flu, and is still the best line of defense,” says Dr. Trachtenberg.