Hey, it's Flora Lickman, and you're listening to Science Friday.

The benefits of getting a vaccine seem relatively straightforward.

Like, you get the shingles vaccine, it protects you from shingles.

But there may be more to the story.

For example, researchers have found a surprising link between getting the shingles vaccine

and a lower risk of developing dementia. And that's not the only vaccine that seems to boost

health in unexpected ways. So what's going on here? Here to get into the details are my guests.

Dr. Pascal Geldsetser is an epidemiologist at Stanford University who's studying the association

between the shingles vaccine and lower rates of dementia.

And Dr. Helen Chu is a physician and epidemiologist at the University of Washington who studies flu, RSV, and COVID-19.

Helen, Pascal, welcome to Science Friday.

Thank you so much for having me.

Yeah, thanks for having us.

Thanks for being here.

Helen, start by orienting us.

Give me some examples of some of the unintended benefits of vaccines, you know, beyond preventing the specific disease they were designed for.

We think of vaccines as preventing the disease that were vaccinating against, flu, or RSV, or COVID.

But oftentimes, these vaccines can have other effects like preventing heart attacks or strokes.

There are a couple of reasons why we think this happens.

The first is perhaps we are not measuring the infections when they occur.

So very well may be that somebody comes in with a heart attack,

and the trigger for that heart attack was a flu infection,

...