Nearly 3 million people in the U.S. have caught the flu this season, and residents are reminded to be aware of possible symptoms after one young girl in Michigan experienced a rare complication.
Back in March 2025, a 9-year-old Michigan girl had caught the flu and experienced the typical flu symptoms, including a fever, chills and fatigue.
The girl’s mom told Newsweek that “nothing seemed alarming at first.”
“When the fever broke after a few days, I thought she was turning a corner,” the girl’s mother said. “Then, suddenly, she started complaining of intense pain in both legs.”
The mother then took her daughter to the emergency room, and after blood work and urinalysis, the doctors diagnosed the girl with benign acute childhood myositis (BACM).
This is a “very rare, temporary complication” of the flu and other infectious diseases, according to the MDHHS.
It primarily occurs in school-aged children, and it most commonly affects boys.
Before the complication affects the kidneys, the first symptom of BACM is typically intense muscle pain, which can sometimes cause a temporary inability to walk. This is what recently happened to the 9-year-old girl from Michigan.
“She told me the pain was deep in her muscles and that it hurt too much to stand. She said her legs felt too weak to support her,” the mother told Newsweek.
The 9-year-old girl was admitted to the hospital for IV fluids and monitoring until she recovered.
Her mother said that after about a week, the girl “made a full recovery and was able to walk again.”
Health officials say people should seek emergency medical care if they see this symptom of intense muscle pain.
The BACM symptoms often appear a few days after a viral illness. Visit here to learn more about the rare complication.
As flu cases continue to rise this season, the girl’s mother is reminding parents to listen to their kids and keep an eye out for complications like the one her daughter experienced.
“I’m sharing our story so other parents know what to watch for,” the girl’s mom said on TikTok.
While influenza is often viewed as an illness that impacts the lungs, health officials are also using this as a reminder to people that the effects of the flu can go beyond the respiratory system.
According to the Centers for Disease Control and Prevention, there have been an estimated 2.9 million flu cases, 30,000 hospitalizations and 1,200 deaths in connection with the flu this season.
The CDC releases a weekly surveillance report map that shows which states have the highest number of visits for respiratory illness.
“This system monitors visits for respiratory illness that includes fever plus a cough or sore throat, also referred to as ILI, not laboratory confirmed influenza and may capture patient visits due to other respiratory pathogens that cause similar symptoms,” the CDC said.
According to the data on the latest map from Dec. 6, Michigan was at a “moderate” activity level, while New York, New Jersey, Louisiana, and Colorado fell within the high to very high influenza activity levels.