WASHINGTON — This year’s harsh flu season in the USA — the most intense in 15 years — has federal health officials trying to understand if it sparked an increase in a rare but life-threatening brain complication in children. The Centers for Disease Control and Prevention (CDC) estimates 19,000 people have died from the flu so far this winter, including 86 children. On Thursday, the CDC reported at least nine of those children experienced brain complications, prompting a request for state health departments to help investigate if there are more such cases.
There is some good news: The CDC also reported that this year’s flu shots are effective at preventing hospitalization from the flu — among the 45% of Americans who got vaccinated. However, it comes a day after the Trump administration canceled a meeting of experts who are supposed to help choose the recipe for next winter’s flu vaccine.
Still, it’s not too late to get vaccinated this year. “If you haven’t gotten your flu shot yet, get it because we’re still seeing high flu circulation in most of the country,” said Dr. Sean O’Leary of the American Academy of Pediatrics.
Flu shot effectiveness varies from year to year. While not great at blocking infections, the vaccine’s main role “is to keep you out of the hospital and to keep you alive,” said Vanderbilt University vaccine expert Dr. William Schaffner.
Preliminary CDC data released Thursday found that children who received this year’s vaccine were between 64% and 78% less likely to be hospitalized than their unvaccinated counterparts, while adults were 41% to 55% less likely to be hospitalized.
Earlier this month, state health departments and hospitals warned doctors to watch for child flu patients exhibiting seizures, hallucinations, or other signs of “influenza-associated encephalopathy or encephalitis” — and a more severe subtype called “acute necrotizing encephalopathy.” Encephalitis is brain inflammation.
On Thursday, the CDC released an analysis of 1,840 child flu deaths since 2010, finding 166 with those neurologic complications. Most were unvaccinated children. However, the agency concluded it is unclear if this year’s nine deaths with those complications — four of whom had the more severe subtype — mark an uptick.
There is no regular tracking of those neurologic complications, making it difficult to find clear answers. In California, Dr. Keith Van Haren of Stanford Medicine Children’s Health mentioned earlier this month that he had learned of about 15 flu-related cases of that severe subtype from doctors around the country and “we are aware of more cases that may also meet the criteria.” He did not specify how many died.
O’Leary, with the pediatricians’ academy, advised parents to remember that this complication is rare — the advice remains to seek medical advice anytime a child with flu has unusual or concerning symptoms, such as labored breathing. Doctors observe more neurologic complications during severe flu seasons, which may be linked to particular influenza strains. Survivors can experience ongoing seizures or other lingering problems, he noted.
Meanwhile, vaccine manufacturers are preparing for the months-long process of developing next winter’s flu shots. An FDA advisory committee was scheduled to meet on March 13 to help choose which flu strains to include, but with that meeting’s cancellation, it is uncertain if the government will decide on its own. “The FDA will make public its recommendations to manufacturers in time for updated vaccines to be available for the 2025-2026 influenza season,” said Andrew Nixon, communications director for the Department of Health and Human Services, in an email.
