The Centers for Disease Control and Prevention said Indiana is experiencing widespread flu activity, and area doctors say people in all age groups are at risk.
Health experts say it's important to know when to ride those symptoms out and when to head to the hospital.
Dr. Charles Miramonti, an ER doctor at Wishard Memorial Hospital, is trying to stay ahead of this year's flu bug and is keeping an eye on who is getting sick and how fast the virus is spreading.
"We are actually very fortunate with our health department here because they have an aggressive surveillance program, not only closely here inside Marion County and the state, but also regionally and nationally," Miramonti said.
Recent Marion County Health Department data shows 226 flu-related ER visits last week, which is more than double the number from this time last year. Health officials told RTV6 it could still get much worse.
So far this season, the flu has killed 15 people in Indiana. At least eight of those were people 50 years old or older.
But family physician Dr. Huma Khan with St. Francis Health said all age groups are at risk.
"It's pretty much across the board," Khan said. "I've seen the 6-month-old coming in... pulling on their ears, they have a runny nose, they've had a fever of 101, and I've seen the 60-year-old that is otherwise healthy."
Doctors say symptoms for the common cold and the flu are similar and include a runny nose, pressure in the ears, an achy feeling and/or a change in appetite.
Doctors said anyone with a fever of 101 degrees or higher should seek medical care.
Typically, experts said, the flu will not require a trip to the emergency room, but Miramonti said keep it in mind if things get worse as days go by.
"Really the trigger is when you have difficulty breathing, when you have a fever that can't be controlled, when you can't keep your medicines down," Miramonti said.
The doctors RTV6 spoke with said it's not too late to get a flu shot. Doctors said even those who got a shot early in the season might want another one, since their first one might have worn off.
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