5 Things That Don't Prove Your Flu Shot Didn't Work

A flu shot won't give you superpowers, but it will help you fend off common strains of influenza. © crossstudio/iStock/Thinkstock

Would you believe that more American adults fear losing a tooth than getting the flu, yet every year as many as 3,300 to 49,000 people in the U.S. alone die from serious flu-related complications [sources: American Association of Endodontists, Neel]?

During flu season each year, anywhere between 5 and 20 percent of Americans will get the flu virus, which will last for about a week (or longer for some symptoms, such as a lingering cough) [source: WebMD]. The only way to prevent it -- and there's really no way to prevent it 100 percent of the time -- is with a flu vaccination (shot or nasal spray). The Centers for Disease Control and Prevention (CDC) recommends that everyone ages 6 months and older be vaccinated every year, yet fewer than 50 percent of Americans get a flu shot [source: Bernard-Kuhn].

What if you were one of those who did get your annual flu shot, but your aches, fever and fatigue would suggest otherwise? Why does it sometimes feel like this year's flu shot didn't work? Despite your sore throat and stuffy nose, don't be so quick to dismiss the vaccine as bunk.