How effective is this year's flu shot?

The flu vaccine for the 2017–2018 season is not doing a good job preventing severe illness caused by one strain of the virus, according to federal health officials.

The vaccine is about 36 percent effective against preventing flu severe enough to send someone to seek medical attention, according to the Centers for Disease Control and Prevention.

This season a type of flu virus called Type A H3N2 has been causing most of the illnesses in the United States, according to the CDC and FDA. The flu shot was only 25 percent effective against that strain.

"Although the initial report of 36 percent overall efficacy for this year's vaccine in the United States that has been reported by our colleagues at the U.S. Centers for Disease Control and Prevention (CDC) is better than some might have predicted, there is still clearly significant room for improvement," Dr. Scott Gottlieb, the FDA commissioner, said in a statement. "The FDA is committed to working together with the scientific and medical communities to better protect the public against the flu and apply lessons learned to next season's flu vaccines."

Dr. Anne Schuchat, the CDC's acting director, said that this season's efficacy numbers show that researchers need to develop better flu vaccines.

"The vaccines that we have today are not the ones that we'd like to have in 10 years," she said.

But experts have said that getting the flu shot is still very important, even at this time of year. This year's vaccine was quite effective against the H1N1 virus and strains of influenza B, officials said.

"Vaccination is one of the best ways known to protect against the flu," Dr. Gottlieb said.

Dr. Marc Siegel, a professor of medicine at NYU Langone Hospital and a Fox News medical contributor, told Fox 5 that he expects a few more weeks of peak flu activity. The vaccine takes about two weeks to work, so don't delay, Siegel said. Go out and get it now.

The vaccine worked relatively well in young children, but it performed worse in older people, including seniors who are most vulnerable, according to the Associated Press.

The numbers could change, though, as more data comes in after the flu season ends.

The flu has killed at least 60 children nationwide this season, which runs through May, the CDC said.

The Centers for Disease Control and Prevention recommends you start taking antivirals within two days of having flu symptoms.

With the Associated Press


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