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Firefighters across the country were some of the first to be offered the COVID-19 vaccine, but many don't want it. In New York and Chicago, only about half of firefighters have gotten vaccinated. Some places aren't even keeping track. Jacob Margolis from member station KPCC reports on how one fire department has helped its crew overcome its hesitancy.

JACOB MARGOLIS, BYLINE: Back in the fall, talk of a COVID-19 vaccine was ramping up. Science and technology looked like they could pull off the impossible. A ray of hope in the darkness as a cure appeared to be on the horizon, but not for everyone.

MICKEY JUAREZ: Well, when it first came out, I was definitely skeptical.

MARGOLIS: Los Angeles County firefighter Mickey Juarez wasn't so sure he wanted the vaccine, for a number of reasons. The biggest of which was his worry that it could be worse for him than COVID.

JUAREZ: What are the long-term effects? I have pre-existing conditions with autoimmune deficiency, if you will, and I was skeptical whether it would affect me adversely or if it would make my condition worse.

MARGOLIS: He wasn't alone. An early survey done by the Los Angeles County Fire Department showed that about 45% of their employees weren't sold on getting the vaccine - just about around where national trends were at the time. It was a big red flag for LA County Fire's medical director Dr. Clayton Kazan. He was hearing all sorts of vaccine conspiracy theories and misinformation coming in from his roughly 3,000 firefighters. So the department had to figure out a way to change minds.

CLAYTON KAZAN: We were all over them about explaining the science...

MARGOLIS: Doing live Q&As, answering any questions people had...

KAZAN: Trying to compete against the noise of some of these social media rabbit holes.

MARGOLIS: And putting out regular informational videos.

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KAZAN: Hi, everybody. I'm coming to you from the COVID bunker. Today we're going to talk a little bit about understanding the SARS-CoV-2 vaccine...

MARGOLIS: But they didn't stop there. They decided that if a firefighter wanted to refuse the vaccine, they couldn't just tick a box online saying no thanks. Kazan says firefighters had to actually go into a vaccination site and decline in person.

KAZAN: If you're sitting at a station with five people who are all kind of grumpy and don't want to get it, it's a lot easier to say no then when you have to show up to an area where you see your friends stepping up and taking it, and now you have a chance to ask your questions, and maybe you'll just kind of roll your eyes and roll up your sleeve.

ALISON BUTTENHEIM: So there's at least two things going on there, right?

MARGOLIS: Alison Buttenheim is a professor at the University of Pennsylvania School of Nursing.

BUTTENHEIM: You have to do something very deliberate to get out of it. So you make opting out harder than opting in. And you make it this sort of social event where you have to reveal to everybody what your choice is.

MARGOLIS: She says that these choices play into our innate desires to both follow the path of least resistance and the need to be part of an in-group, which in this case were people getting the vaccine. And it worked. In the end, around 70% of LA County's firefighters have gotten the vaccine, up from the 55% who'd originally said they'd plan to get it. The whole effort was even enough to convince firefighter Mickey Juarez to get the shot, especially when he heard from medical director Clayton Kazan.

JUAREZ: He's the one that actually changed my mind and put me at ease at the side effects. And, you know, the short-term effects - obviously, there's going to be some, and obviously there were, but they were nothing what I expected.

MARGOLIS: Less vaccine hesitancy is a good thing. Fire season is ramping up in California, and fire agencies are going to need everybody as healthy as they can be. For NPR News, I'm Jacob Margolis in Los Angeles.

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