The 216 pediatric deaths reported by the Centers for Disease Control and Prevention eclipse the 207 reported last year. It’s the most since the 2009-2010 H1N1 global flu pandemic.

It’s a startlingly high number, given that the flu season is still going on. The final pediatric death tally for the 2023-2024 flu season wasn’t counted until autumn.

“This number that we have now is almost certainly an undercount, and one that — when the season is declared over, and they compile all the data — it’s almost certain to go up,” said Dr. Sean O’Leary, of the American Academy of Pediatrics.

There are likely several contributors to this season’s severity, but a big one is that fewer children are getting flu shots, added O’Leary, a University of Colorado pediatric infectious diseases specialist.