It's that time again: Innoculate yourself against common flu shot myths

With the start of the flu season just a few weeks away, health officials are urging everyone six months of age and older to get a flu shot.

But just like the seasons themselves, myths featuring our friend the flu shot seem to keep coming back again. We've rounded up six of the most common ones for ourselves.

1. "The flu shot doesn't work!"

This is sort of true... but way less than its proponents would like to believe. The seasonal flu shot is not designed to protect against every influenza bug. Instead, it targets what scientist believe will be the season's three most common flu strains — and then it's about 70 to 90 percent effective in fighting those strains, according to the Centers for Disease Control and Prevention (CDC).

This year, the vaccine is targeting a variation of last year's swine flu and slight variations in last year's Influenza A and Influenza B viruses, says Dr. Rekha Murthy, director of hospital epidemiology at Cedars Sinai Medical Center in Los Angeles.

But, she says, the flu shot is "not perfect." Some who get the shot will still get sick from the flu strains it targets.

"However, there's a good chance the illness won't be as severe as it might have been if you didn't get the vaccine," she says.

2. "The flu shot can cause the flu."

The flu shot contains dead viruses. Those can't cause the flu.

3. "The side effects of the flu shot are worse than the flu."

A sore arm is likely to be the worst side effect you’ll experience from a flu shot. Only one in every 4 million people suffer any kind of severe allergic reaction to them, the CDC says.

4. "The flu isn't serious."

The CDC reports that each year the flu sends 200,000 U.S. residents into the hospital (mostly those older than 65 years and younger than 2 years), killing 36,000 people nationwide.

5. "If you're healthy, you don't need a flu shot.

While flu shots are especially important for the very old and the sick, healthy people can also become seriously ill from the flu.

6. "If you haven't got your flu shot by December, don't bother."

While public health officials advise you to get your shot as close to the start of the October to March flu season as possible, getting one after that time will still provide you with protection. "It's better to get vaccinated than not," says Murthy.