A 30-year-old patient who thought the coronavirus was a hoax has died after attending a “COVID party” in Texas, a doctor said.

“One of the things that was heart-wrenching that he said to his nurse was, ‘You know, I think I made a mistake,’ and this young man went to a COVID party,” Dr. Jane Appleby, the chief medical officer at Methodist Hospital, said, according to television station KSAT in San Antonio on Friday. “He didn’t really believe. He thought the disease was a hoax. He thought he was young and he was invincible and wouldn’t get affected by the disease.”

A “COVID party” is a gathering held by someone who has tested positive for the coronavirus, the doctor said. People attend to see who gets infected first.

“They’ll have a party to invite their friends over to see if they can beat the disease,” Appleby explained.

Appleby said some young people don’t realize how ill they are.

“People will come in initially and they don’t look so bad. They don’t look really sick. But when you check their oxygen levels and you check their lab tests, they’re really sicker than they appear on the surface,” she told the station.

Appleby advises seeking help if you are not feeling well, have a high fever, cough and severe muscle aches.

“My plea to our community and especially all of our young folks in the community is to take it seriously. Wear your mask,” she said.