LOUISVILLE, KY (WAVE) - If you're battling a nasty cold, fever, or body aches, you're not alone.
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Massachusetts, Georgia, Louisiana and Oklahoma are all reporting a widespread flu outbreak now. If you've had your flu shot, doctors say there are signs the vaccine against the main strain is only about 10 percent effective. Despite this new information, health experts say it's still important to get your flu shot.
If you're older than 65, there are two vaccine options designed to boost immune response, which is important because up to a month after older adults recover from the flu, they're at an increased risk of having a heart attack or stroke.
The CDC is reporting sporadic flu cases in Indiana and regional in Kentucky.
Click here for a list of ways to boost your immune system, and lower your risk of getting the flu.