Flu continues to spread at high levels, as some doctors warn about unusually severe symptoms

“It is too early to know whether activity has peaked for the season,” Budd said.

As of Friday, the CDC estimates that the flu has sickened 14 million people so far, with 150,000 flu-related hospitalizations and 9,400 deaths.

There were at least 13 pediatric deaths from the flu reported last week. Based on prior CDC reports, the number of children who have died so far this season is likely an undercount.

While the elderly are most likely to be hospitalized with the flu, Dr. Dhaval Desai, director of Hospital Medicine at Emory Saint Joseph’s Hospital in Atlanta, said he’s seeing severe cases among all ages.

“It’s not always necessarily the geriatric, older patients,” he said. “I’ve had quite a few younger patients in their 20s to 40s admitted with flu.”

Dehydration, wheezing, severe head and muscle aches and “high fevers that are staying high, above 104,” are the main symptoms driving people to the hospital, Desai said.

Shortness of breath sent Quenten Thomas of Marysville, Tennessee, to the hospital last week. The normally energetic, outgoing 27-year-old was unable to get enough air into his lungs.

“It hurt when he coughed,” his father, Robert Thomas, said. “He was having trouble catching his breath.”

Quenten Thomas, a father of three young children, had to be put on a ventilator but his condition deteriorated quickly. He died from flu complications Jan. 6. He had not received the flu shot this year.

“I’m still in shock,” Robert Thomas said, urging people to take the flu more seriously. “I know I will for the rest of my life.”

Flu symptoms and warning signs

“The biggest thing we’re seeing right now is fevers,” said Dr. Rachael Lee, an associate professor in the division of infectious diseases at the University of Alabama, Birmingham, “as well as fatigue and significant body aches.”

Some have reported unusually severe symptoms, even if they’ve been vaccinated. Desai said he caught the flu in early November, a full month after his flu shot.

He had a high fever, sweats, cough, sore throat and crushing fatigue. He became so dehydrated that he ended up in the emergency room.

Those intense symptoms are hallmarks of how the flu can cause widespread inflammation in the body, putting the “whole body in a stress state,” Desai said.

Fevers of at least 103 degrees that carry on for several days, as well as signs of severe dehydration, also require medical attention, doctors said.

“If you’re having difficulty breathing, that would be an indication to seek emergency care,” said Dr. Andi Shane, head of pediatric infectious diseases at Children’s Healthcare of Atlanta.

A sign of dangerous dehydration is feeling “dizzy when you stand up and so weak that you can’t walk from one side of the room to the other,” Desai said.

People may also develop an intense headache.

Is it too late to get the flu shot?

Anyone ages 6 months and older can still get vaccinated. While it typically takes two weeks after vaccination to build strong immunity, the flu season can last until spring.

“Even if we have peaked, we still have half the season to go,” CDC’s Budd said.

The shot, she said, seems to be a good match to the circulating flu strains.

On Thursday, researchers in Canada reported that the shot is 61% effective in protecting against the predominant strain: H1N1. Among children ages 9 and younger, effectiveness rose to 74%.

Unfortunately, the number of people getting vaccinated this year is down, including pregnant women who are highly vulnerable to serious illness and children, based on early data.

An estimated 10 million fewer people — including children and adults — got their flu shots so far compared to the same time last year, according to the CDC.

“There is some degree of vaccination fatigue in the community,” Desai said.

The majority of his patients hospitalized with flu this season, he said, have not had the flu shot.

While the vaccine does not necessarily prevent a person from getting infected with the flu, experts maintain that it can reduce the severity and length of the illness.

“The flu vaccine is not a particularly good vaccine at preventing flu,” said Dr. Bruce Farber, chief of public health and epidemiology at Northwell Health in New York. “But it’s a very good vaccine for preventing people from winding up in a hospital or being ill or dying of flu.”

While the flu has been spreading rapidly over the last few weeks, Shane said, the new numbers are generally in line with previous, typical flu seasons.

“I think that we are returning to the pre-pandemic flu season,” she said. “If we look and compare what happened last season compared with this season, we do seem to be trending towards our more normal seasonality.”