By Heather Brown

MINNEAPOLIS (WCCO) — A new survey from the University of Chicago finds 41 percent of Americans say they don’t plan to get the flu vaccine this year. Almost one-third of those people say that’s because they believe the shot doesn’t work.

So, how effective are flu shots? Good Question.

Every year, the Centers for Disease Control (CDC) shares how well that season’s flu vaccine works. During the 2017-2018 season, it estimated overall vaccine effectiveness to be at 40 percent

“I think it’s accurate to say we don’t know all the reasons why the vaccine is not completely effective,” says Jennifer Heath, a supervisor within the Minnesota Department of Health’s Vaccine and Preventable Disease division.

(credit: CBS)

Researchers do know some of the reasons: Medical experts don’t always choose the correct strains of the virus in advance, the influenza virus can change before and during production and the vaccine works differently for different people.

“We know we’re not going to prevent every case of the flu, we do know it can save lives,” says Heath. “There’s lot of other ways to think about how this vaccine works.”

Especially vulnerable groups like the elderly, pregnant women, people with underlying conditions and small children appear to benefit the most. According to the CDC, there were 185 pediatric deaths from influenza in 2017-18. Of those, 80 percent were not vaccinated.

Experts say even if some do get the virus, getting the shot beforehand means the illness won’t be as bad.

“Those who have severe outcomes from the flu, the vaccine helps prevent hospitalization and more importantly it helps prevent death,” says Heath.

Already this season, almost 164 million shots have been distributed. Even at a 30- to 40-percent effectiveness, experts say that’s still protecting a lot of people.

“That means they’re not getting sick, they’re not spreading flu, they’re going about their daily lives,” says Heath. “You’re protecting other people because you’re not spreading the disease to them.”

Heather Brown