Four children have died from the flu in Massachusetts so far this season, public health officials say.

The deaths occurred in recent weeks as peak flu season gets underway, according to the Department of Public Health. The Boston Public Health Commission said Tuesday that two of the deaths were children in the city under 2 years old. 

"These viruses are serious, dangerous, and life-threatening. We are seeing children who are seriously ill, families grieving devastating losses, and hospitals under capacity strain," Public Health Commissioner Dr. Robbie Goldstein said in a statement. 

"Would not be surprising to see more"

There were 10 pediatric flu deaths in the 2024-2025 season, the department said - a record-high. 

"It's early in the season yet and it would not be surprising to see more, sadly," said Dr. Larry Madoff, the medical director of the department's bureau of infectious disease and laboratory sciences. "It's shaping up to be a severe early flu season."

Dr. Madoff said children under the age of 2 are most at risk of dying from the flu, but doctors are also seeing severe cases in children as old as 5. 

"Kids do get quite ill with the flu, they also spread it to their classmates and to their parents and family at home," he said.

Flu activity is now "very high" in the state for the first time this season. Nine percent of all hospitalizations in the state are associated with the flu, compared to 5% the previous week.   

There have been 29 adult deaths from the flu this season. The state is also investigating two possible COVID-associated deaths and one RSV-associated death in patients under 18 years old.

Flu vaccination push

Public health officials are stressing that it's not too late to get a flu or COVID vaccine. Flu and COVID vaccination rates in Massachusetts have been "really lagging" this year," Dr. Madoff said, with just 1 out of every 9 residents vaccinated against COVID and 1 in 3 vaccinated against flu.

"These deaths underscore the need for kids to be vaccinated," Dr. Madoff said. "Everyone should get a flu vaccine, everyone over the age of 6 months."

Health officials in the city of Boston said there was a 126% increase in confirmed flu cases between Dec. 14 and Dec. 27, and hospitalizations almost tripled. The biggest jump in cases was reported among children.

"Flu cases are surging in Boston, and we are seeing an uptick in serious cases involving children, including the tragic deaths of two very young children," Boston Public Health Commissioner Dr. Bisola Ojikutu said in a statement. "Parents should get their children ages six months and older vaccinated as soon as possible to decrease the risk of severe complications."

Boston is holding free flu and COVID vaccine clinics for children 6 months and older in January. Click here for more information.