When his brother first caught the novel coronavirus, Mark Valentine didn’t think he was suffering too much.

Phil Valentine continued posting regularly on Facebook, joked about his condition and even hosted a segment for his conservative talk radio show on WTN-FM in Nashville. He had chosen not to get the vaccine and frequently mocked Democrats’ campaigns to drive more people to get the shot. When the brothers spoke on the phone a few days after Phil tested positive in early July, he told Mark he was already feeling better.

“He said, ‘I don’t think it’s going to be a big deal,’" Mark Valentine told The Washington Post on Sunday. “I frankly quit worrying about it.”

But by the end of the week, after nearly recovering, Phil Valentine’s health began a rapid descent. His family persuaded the 62-year-old to check into the emergency room. Medical scans showed the coronavirus infection had caused pneumonia in his right lung, Mark Valentine told The Post.

Not long after Phil Valentine was admitted to the hospital, the Tennessean reported, he and his family began thinking differently about the vaccine.

“I changed my mind as soon as I saw what was happening here,” Mark Valentine told The Post. “I immediately went and got the vaccine.”

He said his brother’s thinking also changed.

“If Phil were able to conduct this interview, he would tell you while he has never been an anti-vax person, he has always been a pro-choice person,” his brother told The Post. “What he regrets is not being more vehemently pro-vaccine, and when he gets back on the air, that’s exactly what he’s going to tell people.”

The delta variant has become the dominant strain of coronavirus in the United States, resulting in a rise in infections and hospitalizations. (John Farrell/The Washington Post)

The Valentines are among a large number of Americans who had reservations about getting the coronavirus vaccine when it became widely available this spring. As politicians drew partisan battle lines around the handling of the pandemic, some Republicans grew wary of trusting the vaccine that had been rapidly developed when President Donald Trump was in office.

But with coronavirus cases again on the rise, especially among the unvaccinated, many people who were formerly skeptical of the vaccine have changed their tune.

Sarah Sanders, Trump’s former press secretary, penned an op-ed in the Arkansas Democrat-Gazette on Sunday explaining why she decided to get vaccinated and declaring “the Trump vaccine works and is saving lives.” At a rally in Arizona on Saturday, Trump told his supporters to get the vaccine, while blaming President Biden for lagging inoculation rates.

“I recommend that you take it,” Trump said, “but I also believe in your freedoms 100 percent.”

Yet for some, the realization that the vaccine can prevent a life-threatening illness only comes after a loved one catches the virus.

Even after he tested positive for the coronavirus, Phil Valentine and his family questioned the value of getting a vaccine when the politicians and public figures they respected had not advised it.

For days after contracting the novel coronavirus, Valentine believed his body would beat back the worsening infection with the help of vitamin D supplements and ivermectin, a drug typically used to treat parasitic worms, lice and skin conditions that the Food and Drug Administration has not approved to treat covid-19.

“Doing my patriotic duty for natural herd immunity,” the radio-show host said on Facebook on July 14, when he started to feel better days after falling ill.

But when breathing became difficult enough to send him to the hospital, he and his family realized how dangerous the virus could be.

Doctors had him shift from his back to his stomach to stop fluid from pooling in his lungs. During the day, doctors put him on high-flow oxygen therapy. At night, he breathed with the help of a BiPap machine, a type of ventilator that does not require being intubated.

The family also learned that most of the people enduring life-threatening covid-19 infections at the hospital had not been vaccinated, Mark Valentine told The Post.

“The problem with this is that it has become a political decision,” he said. “The truth is 97 percent of the people in the hospital right now are unvaccinated.”

The number of unvaccinated people who have been hospitalized with covid-19 is far higher than the number of vaccinated people.

In Tennessee, where Phil Valentine lives, the state recently reported that 97 percent of hospitalized covid patients had not been vaccinated. In neighboring Arkansas, 98 percent had not received any of the three vaccines available in the United States.

Even in Maryland, where more than 75 percent of the adult population has received at least one vaccine dose, 93 percent of those in the hospital were unvaccinated, as was every single person who died from the virus in June.

After sharing the story of his brother’s ordeal in the hospital, Mark Valentine told The Post that dozens of WTN-FM listeners began writing to the family to say they have decided to get vaccinated.

“It’s overwhelming and heartwarming,” Valentine said. “And for these people who are getting vaccinated, we’re just elated about that.”