Flu season is upon us.

"It's hit us, it's hit us," Dr. Ramindra Walia, chief medical officer of United Community & Family Services in Norwich, said Friday. "Suddenly it spiked just before the holidays."

Walia said that over the last two weeks, about 10 patients per day have been coming to the Norwich clinic with flu symptoms, many of them children. Symptoms seem to be most severe in young children, he said, some of whom are suffering with fevers of 102 to 103 degrees for three to four days and are sick for 10 days or longer.

"We're counseling our parents to give their kids fluids, fluids, fluids," he said.

None of the patients treated at UCFS have had to be hospitalized, he said, although one infant was sent to the emergency department at The William W. Backus Hospital to receive rehydration treatment.

The federal Centers for Disease Control on Dec. 20 said flu had reached epidemic levels nationwide. Connecticut is one of 36 states where flu cases are "widespread," according to the state Department of Public Health. As of Dec. 27, 180 Connecticut residents have been hospitalized with the flu since Oct. 1, the department said, and 444 confirmed flu cases have been reported at outpatient clinics. Many people who get the flu aren't counted in that number, however, because they either don't go to the doctor or the doctor didn't conduct the confirmatory test.

Confirmed flu cases thus far are highest in New Haven and Fairfield counties, with 141 and 137 cases, respectively. The state health department said last week that as of Dec. 27, New London County had 24 confirmed cases.

At Lawrence + Memorial Hospital in New London and its associated outpatient offices, there have been 21 confirmed cases of the flu since Dec. 16, said Rhonda Susman, manager of infection prevention for L+M and The Westerly Hospital. Twelve patients had to be admitted to the hospital, five of whom also had pneumonia.

Susman said most of the flu patients had the H3N2 Type A flu, the most prevalent type circulating this year. Although this year's flu vaccine is not an exact match for the prevalent strain, Susman said it still offers some protection and lessens the severity of symptoms for people who do get sick.

"It's not too late to get your flu shot," she said.

Along with getting vaccinated, she said the best defense against the spreading the flu is diligent hand-washing and keeping coughs covered.

"And keep your environment clean, keep your hands away from your face and get good nutrition and sleep," she added.

At Backus and its affiliated outpatient offices, there have been 97 confirmed flu cases since Oct. 1, 59 of them since the beginning of December, said Emilee Stroup, regional infection control officer for Backus and Windham hospitals. Thirty-three patients have been hospitalized, she said.

"Thirteen of the cases were just within the last two days," Stroup said.

On Dec. 4, the CDC warned that this flu season could be severe and urged anyone who hadn't yet received the vaccine to do so. It also recommended prompt treatment with antiviral drugs for anyone who has flu symptoms and is at high risk of complications. The last time H3N2 was the predominant strain, in 2012-13, 2007-08 and 2003-04, saw the highest mortality rates from flu in the past decade, the CDC noted.

Symptoms of the flu include sudden fever, muscle aches, sore throat, dry cough, runny nose, headaches, burning sensation in the chest, eye pain and sensitivity to light. Young children can also have vomiting and diarrhea, Susman said.

The CDC recommends vaccination for everyone six months or older. Those at greatest risk for complications from the flu are those aged 65 and older; children age 2 and younger; those with chronic medical conditions; and pregnant women.

j.benson@theday.com

Twitter: @BensonJudy