CHAMPAIGN, IL (Chambana Today) — As flu cases rise, doctors are seeing an increase in severe and sometimes life-threatening complications, particularly in children. Though often dismissed as a routine seasonal illness, influenza can affect the lungs, brain, heart and other vital organs.
“The flu damages the body’s natural defenses,” said Mustafa Bakir, MD, a pediatric infectious disease specialist with OSF HealthCare. “If the virus destroys the mucosal sites, they can go wherever they aren’t supposed to.”
Influenza weakens the respiratory tract’s protective barriers, allowing bacteria and viruses to spread and cause secondary infections. Among hospitalized patients, up to one-third develop severe pneumonia, and about 10% experience neurological symptoms such as febrile seizures, Bakir said.
During the 2024–2025 season, the U.S. Centers for Disease Control and Prevention reported 109 cases of flu-related encephalitis in children nationwide. Three cases were treated at OSF HealthCare Children’s Hospital of Illinois in Peoria. Encephalitis can cause permanent brain damage or death.
Doctors have also reported rare complications such as necrotizing pneumonia, which destroys lung tissue, and heart inflammation that can lead to heart failure. Neuromuscular conditions, including Guillain-Barré syndrome, have also been linked to influenza.
Multiple flu strains are circulating this season, including Influenza A and B. Despite the risks, vaccination rates remain low. In Illinois, only 24.4% of residents are vaccinated against the flu, far below the level experts say is needed to prevent outbreaks.
“Influenza is not just a seasonal inconvenience,” Bakir said. “Prevention and early medical care are critical to saving lives.”
To read more from Dr. Bakir, read OSF’s full release on the subject here.
