The United States is experiencing the highest levels of hospitalizations from influenza that it has seen in a decade for this time of year, the head of the U.S. Centers for Disease Control and Prevention (CDC) said on Monday, adding that 14 children have died so far this flu season.

CDC Director Rochelle Walensky added that U.S. hospital systems also continue to be stressed with a high number of patients with other respiratory illnesses such as respiratory syncytial virus (RSV) and COVID-19.

There have been at least 8.7 million illnesses, 78,000 hospitalizations, and 4,500 deaths from flu so far this season, according to CDC estimates. It urged people to get vaccinated.

“Especially for RSV and flu, these levels are higher than we generally see this time of year,” Walensky told reporters in a telephone news briefing. She said flu season started earlier and “hospitalizations for flu continue to be the highest we have seen at this time of year in a decade.”

Respiratory viruses are spreading as people gather indoors due to the colder weather. People also likely have weakened defenses after not being exposed to flu and RSV while working or schooling from home during the COVID-19 pandemic.

Vaccination rates for people at higher risk from the flu – those 65 and older, children and pregnant women – are also lower than at this time last year, Walensky added.

About 12% fewer pregnant women have been vaccinated so far this season compared to last season, and about 5% fewer children, Walensky said.

Between Oct. 1 and Nov. 26, the rate of hospitalization for flu in the United States was 16.6 per 100,000 people. In the past 10 years, the cumulative rate during the same week of the year typically range from 0.1 to 2 per 100,000.

COVID-19 cases have risen following the Thanksgiving holiday and COVID-related hospitalizations have also increased about 15% to 20% over the last week, Walensky said.

Walensky, joined by Dr. Sandra Fryhofer, an internist who chairs the American Medical Association board, urged people to get flu shots now – despite possibly being wary or tired of vaccinations – saying it was not too late.

“This year’s flu season’s off to a rough start,” Fryhofer said. “It started early, and with COVID and RSV also circulating, it’s a perfect storm for a terrible holiday season.”