Intensive care units in hospitals across the country are filled with patients suffering from COVID-19. Many are hooked up to life support systems, and regret that they didn’t heed expert advice to get vaccinated against the virus or take mitigation measures.

“If I would have known six months ago that this would be possible, this would have been a no-brainer,” said Joe Gammon from his bed in the ICU at Ascension Saint Thomas Hospital in Nashville, Tenn. “But I honestly didn’t think I was at risk.”

According to Kaiser Health News, Gammon, the 45-year-old father of six children, has been in critical condition with COVID-19 for weeks. Tennessee hospitals are setting new records each day with more COVID-19 patients than ever before. They are caring for 3,846 patients of the more than 100,000 hospitalized patients with the virus as of Sept. 9.

With the Delta variant surging across the country, recent data released by the federal government shows that in hospitals throughout the South, as well as in California and Oregon, more than 50% of patients are being treated for COVID-19. Anything above 20% represents “extreme stress” for hospitals, says NPR, according to a framework developed by the Institute for Health Metrics and Evaluation at the University of Washington. The most critical patients are all unvaccinated, says KHN.

Gammon, a truck driver, said he was dissuaded from getting vaccinated by talk shows downplaying the seriousness of the virus and promoting personal freedom. He’s now a firm believer in the vaccine and is thankful he didn’t transmit the disease to anyone else.

“Before you say no, seek a second opinion,” he said, according to KHN. “Just to say ‘no’ is irresponsible. Because it might not necessarily affect you. What if it affected your spouse? Or your child? You wouldn’t want that. You sure wouldn’t want that on your heart.”

Gammon is on last-resort life support and even if he makes it, he’s facing months of rehabilitation, permanent disability or lifelong dependence on oxygen because of the extensive damage to his lungs caused by COVID-19.

Lydia Mobley, an intensive care unit nurse working at a hospital in central Michigan, says she sees many patients on every shift who regret not taking the warnings seriously.

“A lot of times before they’re intubated — which means put on a ventilator because they can’t breathe on their own — when they’re still struggling to breathe, and they’re saying, ‘Well, I didn’t know COVID was real, and I wish I’d worn a mask.’ And then it’s already too late,” she told NPR’s All Things Considered. “You can see the regret as they’re struggling to breathe and it’s finally hitting them that this is real. It makes me very sad.”

While most of Mobley’s patients are in their 40’s and 50’s, she has treated many elderly patients who probably contracted the disease from relatives.

She says those families are also struggling with regrets and are “very remorseful about not doing more to keep their family members safe.”