Many believe that once they've had the flu, they're immune for the rest of the winter.
But unfortunately, that is not the case.
You can actually get the flu more than once, as 7-year-old J.J. Butson was disappointed to find out.
The boy’s mom, Brandi, says his second bout with the flu was way worse than the first.
“He had a temperature of 104.6,” she told Inside Edition. “We rushed him to the doctor. I couldn't believe it because I thought you could only get the flu once.”
He says he hopes he gets well in time for his upcoming eighth birthday party.
The young boy is not the only person to catch the virus twice.
Omaha radio personality Jason Spicoli says he's also contracted the flu more than once.
“I had it the second time and I’m thinking, ‘Oh boy, here we go again. Here come the shakes, here comes the nausea,'" he told Inside Edition.
Dr. Mehmet Oz told Inside Edition that getting the flu several times is not unheard of since there are many different strains of the virus.
“So you can get a really bad one, then get a less bad one, or vice versa,” he said.
Hair stylist Michelle Crane caught the flu once and, just two weeks later, she caught a different strain.
"I didn't think I could get it again, let alone so quickly," she said.
Dr. Oz says a flu shot is still the best bet for prevention.
“The vaccine covers several of the bad strains. It doesn't cover them all; it doesn't cover them all well. But it's better than nothing, which is why I still think it's worth getting,” he said.