(CNN) Jim Sells is 71, a self-described "strong conservative" who's on social media all the time. As the pandemic unfolded in the United States, his online social network was the source of a lot of his ideas about Covid-19 and what the risks of the virus could be.
It was there where he read about a high survival rate among people who'd had Covid-19, and where he saw people questioning whether masks were effective. Sells said he and his friends didn't think addressing the pandemic was particularly urgent. And based on posts he saw on social media, Sells decided he didn't need to be vaccinated against Covid-19.
"That attitude is what left me totally unprepared for Covid," he said.
In late July, Sells, a retired pilot, flew from Georgia, where he lives, to attend an air show in Wisconsin.
"My last post before I disappeared was that event, and I posted, I'm with 500,000 people, hardly a single mask, and it smells like freedom," Sells said.
Three days after the show, Sells had a fever and felt extremely fatigued. While his fever broke a few days later, the exhaustion did not lift. He hoped upping his vitamin intake and resting would bring him some relief. It didn't.
After a televisit with his doctor, Sells was tested and learned he was positive for Covid-19.
Later, he spoke with a friend who suggested he go to the hospital to get a breathing treatment.
Sells didn't realize how serious his situation had become. In the hospital, he said his doctor told him they didn't know if they could help him, but they were going to do everything they could.
"They put an oxygen mask on and cinched it down real tight. They started putting the heart monitors on me, and then asked me if I wanted to be resuscitated. And I'm in total shock," he said.
Public health experts have long worried that misinformation is leaving parts of the United States unprepared to stay safe and healthy in the face of Covid-19, or other potential health problems.
Surgeon General Dr. Vivek Murthy has called misinformation an "urgent threat." In July, Murthy released an advisory report saying "Health misinformation is a serious threat to public health. It can cause confusion, sow mistrust, harm people's health, and undermine public health effort."
With Covid-19 vaccines recently available for children ages 5 to 11, Murthy worries the impact misinformation can have on vaccine uptake for that age group.
"We have to guard against that misinformation," Murthy said in an interview with CNN Chief Medical Correspondent Dr. Sanjay Gupta at the Citizen by CNN event on Thursday.
"I want parents to know that their questions are important," Murthy said. "But it's important that they also go to credible sources to get answers to those questions, like their doctor, their children's hospital, their local department of health or the CDC."
But vaccine hesitancy exists across age groups, not just among parents of young children. A Kaiser Family Foundation poll released in September found that fears about rising Covid-19 cases, hospitalizations and deaths from the Delta variant drove recent increases in vaccination. Still, according to the CDC, only about 78% of the US population age 12 and older has received at least one Covid-19 vaccine dose.
Based on what Sells had seen online, he didn't expect Covid-19 would leave him hospitalized and hardly able to breathe.
"Social media is full of this information to address your agenda. The algorithm sends just what you want to hear right to you," he said. "And I was filled with this information."
In recent weeks, social media giant Facebook has been under the spotlight for its role in allowing misinformation to spread. Despite public declarations that the company has prioritized resources to tackle misinformation on their platform, internal Facebook documents provided to Congress say otherwise.
"We have no idea about the scale of the [Covid-19 vaccine hesitancy] problem when it comes to comments," an internal research report posted to Facebook's internal site in February 2021, a year into the pandemic, noted. "Our internal systems are not yet identifying, demoting and/or removing anti-vaccine comments often enough," the report pointed out.
In the hospital, Sells was treated with oxygen and the antiviral remdesivir, as well as steroids and blood thinners.
Sells began to stabilize 18 hours after he was admitted to the hospital. He spent the next 16 days at the hospital, most of it in the ICU.
While Sells didn't have any preconditions that made him more vulnerable to Covid-19, his age put him at higher risk for severe illness.
"Certainly, elderly folks may tend to do not as well. But Covid is a very, very variable disease," said Dr. Arvind Ponnambalam, Sells' doctor and a pulmonologist at Piedmont Fayette Hospital in a suburb of Atlanta. "It can be very random in different patient populations. And oftentimes, it's very difficult for us to tell how someone is going to do."
Sells is still going to physical therapy to build back his strength and stamina. Even minor exertion still leaves him exhausted.
What frustrates him the most, though, is that this was preventable.
Sells says he plans to get the Covid-19 vaccine next week, now that he has been cleared by his doctor.
"I don't want anybody to go through what I went through," Sells said.
"We really need the world to know the truth and the consequences of not being vaccinated."
Sells said he has already lost friends over his recent advocacy for vaccines, but it's worth it.
"They don't know what I now know," he said. "We've got to get the word out so that we can get our hospitals back and slow down the rate of deaths."