Flu cases started to peak across the United States in mid-December, and the peak ended in early February, a new report from the Centers for Disease Control and Prevention has found. Statistics point to this flu season as a relatively mild one.

There were 22,641 lab-confirmed cases of influenza in the country between Oct. 3 and Feb. 5, according to the report released today (Feb. 17).

The number of cases stayed low between October and mid-December before the winter peak, according to the report. During the week ending Feb. 5, high numbers of influenza-like illness cases were seen in 19 states, including New York, South Carolina, Maryland and Texas. Nine states reported a moderate number of cases, and 12 states reported a low number of cases, the report said.

Flu-related deaths in children tripled in January to 30 deaths, but that number is still low compared with the total 329 children's deaths reported during last year's flu season, the report said.

Even though it differs from year to year, this year has been quite normal for a flu season, compared with last year's pandemic, said Alicia Budd, an infection control epidemiologist at Johns Hopkins Medicine in Baltimore.

"Some years, flu comes a little earlier, some later," Budd told MyHealthNewsDaily. "This year, it's right in the middle of when you'd expect it."

Different strains

This flu season seems to be milder than last, largely because a lot of people have built up antibodies to the H1N1 strain from last flu season, said Dr. Anna-Kathryn Rye, a pediatric infectious disease specialist at the University of South Carolina School of Medicine.

But people tend to forget that the flu can be deadly, and its easiest targets are the very young and the very old, Rye said.

The most common strains this year are influenza A strains H3N2 and H1N1, which have accounted for 73 percent of all flu cases, and the influenza B strain, which has accounted for 27 percent of all flu cases , the report said.

All three strains were included in this year's flu vaccine. Among the A strains, the H3N2 strain is more common this year than H1N1, which was responsible for the swine flu pandemic last season.

The strains vary with regions. In Baltimore, the influenza A H1N1 strain is the most common, Budd said. In South Carolina, it's the influenza B strain, though Rye said there's influenza A activity there as well.

Preventing the flu

In general, flu peaks typically only last a few weeks, so people should expect flu cases to decrease from here on out, Rye said, but added it's still important to take preventive measures.

Hand-washing is one of the most important things one can do to protect against the flu, she said.

"Influenza gets passed around in day cares and schools, so unfortunately there's not a lot to do with that besides making sure [your kids are] washing their hands," Rye told MyHealthNewsDaily.

Although it's tempting to give a sick child symptom-clearing medicine and then send him off to school, it's better to keep him at home to avoid infecting other kids, she said.

Getting vaccinated is a big part of prevention, Rye said. People ages 6 months and older should be vaccinated once a year, she said.

Pass it on: The flu peaked during the month of January. This year's flu season is a lot calmer than last year's flu season, when the H1N1 strain caused a pandemic.

Follow MyHealthNewsDaily staff writer Amanda Chan on Twitter @AmandaLChan.