Flu season got off to a fast start and shows no sign of slowing. On Friday, the Centers for Disease Control and Prevention reported that flu activity continues to rise across the country, with an estimated 2.6 million flu illnesses reported so far this year.

Of those patients, 23,000 required hospitalization and 1,300 people died from the flu, including 10 children, the CDC said.

The early start to flu activity makes experts "a little concerned that we'll have a prolonged influenza season," said Dr. William Schaffner, an infectious-disease expert at Vanderbilt University and medical director of the National Foundation for Infectious Diseases.

What's more, this season "is starting out in a distinctive way," Schaffner said. The predominant flu virus currently circulating is one that typically doesn't pop up until the end of the flu season, in early spring, a B/Victoria strain.

For a B strain to be "so prominent is weird" this early in the season, he said. Typically, influenza A virus strains are responsible for the most illnesses each year.

B viruses can infect anyone, but it generally strikes children and young adults more than the elderly.

"We are always concerned about children under the age of 4, particularly children under the age of 1 because they can't get an influenza vaccine until they're six months of age," said Dr. Rachael Lee, chief epidemiologist at the University of Alabama at Birmingham Hospital.

Alabama is one of the 23 states experiencing widespread flu activity, according to the CDC. Most states in the West, East and all along the southern border have elevated levels of flu. This time last season, only three states reported widespread activity.

Despite the intense start of flu season, the number of hospitalizations reported is the same as this time last year. That may be attributed to the influenza B strain affecting younger, otherwise healthy people. Most of the time, flu complications occur in the elderly.

Flu season usually peaks between December and February, but the CDC said Thursday that there's a 45 percent chance flu activity will peak by the end of the year.

According to the latest #FluSight flu forecast, there is a 45% chance that flu season will peak in late December. Flu activity usually peaks between December and February. Learn more from the latest #FluSight forecast: https://t.co/Jc5L0a4pxO — CDC Flu (@CDCFlu) December 12, 2019

Still, the flu is notoriously fickle. "If I think I know what's going to happen, it'll probably do something different," said Lynnette Brammer, who heads the CDC team charged with collecting flu data from all over the country to produce the agency's weekly national flu report.

Flu season is "really unpredictable," Brammer said.

She added that she would not be surprised to see an increase in influenza A viruses this flu season.

Protect yourself from the flu

Flu season generally lasts well into spring, so there's still time to get the flu shot if you haven't already. The FluMist nasal spray is also available for kids or needle-averse people.

Every major medical group recommends getting the yearly vaccine, saying it's the best option available for preventing flu. Infectious disease experts say that this season's shot appears to be a good match so far, though they won't fully understand how well it's working until the end of the season.

If you do become ill after getting your flu shot, studies have shown the vaccine can reduce the severity and length of illness — meaning, how awful you feel and for how long.

Prescription antiviral drugs, such as Tamiflu, can also help make you feel better, faster, but they work best if given within the first day or two after flu symptoms develop.

There are other proven ways to reduce the chances of spreading viruses this flu season: covering your mouth and nose when coughing and sneezing, staying home when you're sick, and good old-fashioned hand-washing with soap and water.

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