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How Long Are We Contagious? Good Question

MINNEAPOLIS (WCCO) -- Anyone who's had to flu knows it can knock you a person out for days. Schools and daycares often want kids to stay home until they are fever-free for 24 hours.

That had Patrick from Minnetonka wanting to know: How long are we contagious? Good Question.

"It depends a little on the virus," says Dr. Stacene Maroushek, a pediatric infectious disease specialist at Hennepin Healthcare.

She says people infected with influenza are contagious a day or day and a half before they show symptoms. That's partly why flu is considered a smart virus that spreads easily. People are also contagious during the average of the three to five days that have a fever. Then, Dr. Maroushek says people continue to shed the virus for the next four to eight days.

Colds are a different story because they comprise so many different kinds of cold viruses. But, people can still be contagious with the common cold, or rhinovirus, four to eight days after symptoms have subsided.

Dr. Maroushek says that doesn't mean people need to take off a week of work or school every time they get a cold, but she does say it's important to stay home with a fever, heavy runny nose or bad cough.

"My biggest message to everyone is to try not to work through it, but even when you come back, you need to wash your hands," she says.

The CDC recommends people wash their hands often and for 20 seconds at a time.

Often, schools or daycares will won't allow children back until they've been fever-free for 24 hours. Dr. Maroushek says that's because the time during a fever can be the most contagious, schools don't want to have to give Ibuprofen or Tylenol and people tend to feel better after the fever breaks.

"You are still contagious," she says. "It's a balance between decreasing shedding and work productivity."

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