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Among the COVID vaccinated in the U.S., frustration is growing towards those who chose not to get the shot. The argument is that the unvaccinated may be making the pandemic last longer. As Jackie Fortier of member station KPCC in Los Angeles reports, vaccinated people who catch breakthrough COVID-19 infections have a more personal anger.

JACKIE FORTIER, BYLINE: In early July, Jenny and Mike McHargue stood in line with their two teenaged daughters for the "Peter Pan" ride at Disneyland. It was their first big outing in months. The family was fully vaccinated, and they were excited to spend a few days at the park. But seeing thousands of people without masks was jarring.

JENNY MCHARGUE: Mike even said that first day the probability of people walking in the park that had COVID and from there that had the actual delta variant...

FORTIER: ...Was high. They were there for three days and wore masks and crowded areas. They did take them off when they were eating. The night they drove home, Jenny felt. ill.

J MCHARGUE: Then a couple of days later, I really was noticing I couldn't smell and taste.

MIKE MCHARGUE: She opened a jar of garlic to see if she could smell it. She said, I think I can smell this. And it almost knocked me over on the other side of the room. And I said, I'm going to go get us COVID tests right now.

FORTIER: Both Mike and Jenny tested positive for COVID-19.

J MCHARGUE: I did start crying because it was like we did everything right.

FORTIER: Then their younger daughter tested positive.

J MCHARGUE: And now - what? - we have to be in another kind of forced lockdown, you know, just when we had this little bit of freedom?

FORTIER: Her disappointment is understandable because they took all the precautions recommended at the time. Masks work by reducing the amount of virus a person inhales, says Andrew Noymer, who teaches public health at the University of California, Irvine.

ANDREW NOYMER: The absolute best practice is to vaccinate and to mask.

FORTIER: Taking your mask off in public to eat or drink cuts down on your protection.

NOYMER: These measures work synergistically, so vaccination and masking is more than just one plus one. It's more like 10 times 10.

FORTIER: LA County reinstated an indoor mask mandate in July. Now the focus is on unvaccinated people who make up the vast majority of new cases. That's contributed toward political support for more coercive measures.

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NURY MARTINEZ: We are now half a year into our vaccination campaign. And we need the unvaccinated Angelenos to stop dragging their feet.

FORTIER: LA City Council President Nury Martinez wants to require vaccination checks before people can enter indoor places such as restaurants and movie theaters.

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MARTINEZ: And quite frankly, I think it's safe to say that we're getting tired of protecting people who don't want to protect themselves or get vaccinated.

FORTIER: In recent weeks, the vaccination rate in California increased by 41%. But that uptick is coming too late for the vaccinated who are already infected.

J MCHARGUE: It's frustrating.

FORTIER: Now more than a month since their trip to Disneyland, Jenny McHargue has regained most of her sense of smell. But Mike has developed cognitive problems caused by COVID-19.

M MCHARGUE: I've just kind of had it. There's no rational and no emotional argument that adds up against getting your damn shot. There just isn't.

FORTIER: Mike is scared his cognitive impairments, like difficulty forming sentences, will prevent him from working as an author and podcaster. And he's angry at people who choose to decline the shot.

M MCHARGUE: Are we a people that come together and make things better or are we people who give up when faced with the slightest inconvenience? And I see red because all around me I start to see more and more signs that maybe Americans are just the give-up crowd.

FORTIER: And he says all people are being asked to do is to take a free, safe vaccine that saves their lives and the lives of others.

For NPR News, I'm Jackie Fortier in Los Angeles. Transcript provided by NPR, Copyright NPR.