With tens of thousands of patients flocking to hospitals and at least 37 children dead, this year’s flu season is shaping up to be the worst in nearly a decade – and it’s not over yet.

At a time when experts hoped new cases would start tapering off, federal health officials said Friday that the number of patients seeking care for flulike symptoms continues to rise sharply.

Nearly 12,000 people have been hospitalized with confirmed cases of flu, an increase of 3,000 in just one week, according to the Centers for Disease Control and Prevention. The latest report, for the week ending Jan. 20, shows the rate of people seeking care now rivals that of the swine-flu pandemic of 2009.

In Florida, West Boca Medical Center in Boca Raton has seen a surge of patients. “We think it may be peaking,” said Adam Leisy, head of the emergency room, “but who knows what the next few weeks will bring.”

Leisy said his hospital has been flooded with elderly snowbirds – often already dealing with chronic conditions and now wheezing from coughs and struggling with fever.

In California, some hospitals have pitched tents outside their ERs to cope with the crush of patients; some facilities there have flown in nurses from out of state. Doctors have worked double and triple shifts. In Chicago, a shortage of patient beds has left ambulances idling outside hospitals.

In New York, state leaders last week issued an emergency order allowing pharmacists to give vaccines to children.

The toll on children has been especially severe. CDC officials said the pediatric death count is likely to approach, if not exceed, the 148 deaths reported during the especially severe flu season of 2014 and 2015. That season ended with 56,000 flu-related deaths, 710,000 people hospitalized and 16 million who sought care from a clinician or hospital.

This year’s intensity has been driven by a particularly nasty strain of the virus known as H3N2. Another strain has also begun showing up, hitting baby boomers especially hard, CDC officials said Friday, although experts have not figured out exactly why.

The CDC says the number of pediatric deaths is probably more than the 37 reported, because if often takes longer for deaths outside hospitals to be reported to authorities. The real number may be twice as high, officials said.

“You hear people talking about how serious it can get, but you never think it’s going to happen to you,” Anne LaMontagne, 41, said as she sat by her son in a Minneapolis hospital.