Editor’s Note: CNN Chief Medical Correspondent Dr. Sanjay Gupta is a practicing neurosurgeon and the author of the new book “World War C: Lessons from the Covid-19 Pandemic and How to Prepare for the Next One.”

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In today’s highly segmented media world, most of the people who watch and listen to me every day on CNN have already received and accepted the message about the utility of vaccines, the importance of masks and how we can all work together to put an end to this pandemic. So I realized that if I was serious about trying to communicate public health, I needed to go to a less comfortable place. I needed to go into the lion’s den and accept an invitation to sit down with Joe Rogan for more than three hours.

I don’t think I have ever had a conversation that long with anyone. Seriously – think about that. We sat in a windowless podcast booth with two sets of headphones and microphones, and a few feet between us. Not a single interruption. No cellphones. No distractions. No bathroom breaks.

At a time when there is a desire for shorter, crisper content – responding to abbreviated human attention spans – one of the most popular podcasts in the country features conversations that last exceptionally long and go particularly deep.

Many friends cautioned me against accepting Joe’s invitation. “There is little room for reasonable conversations anymore,” one person told me. “He is a brawler and doesn’t play fair,” another warned. In fact, when I told Joe early in the podcast that I didn’t agree with his apparent views on vaccines against Covid, ivermectin and many things in between, part of me thought the MMA, former Taekwondo champion might hurtle himself across the table and throttle my neck. But, instead he smiled, and off we went.

Here is a headline: Joe Rogan agreed to get vaccinated

OK, I am embellishing here, but Joe Rogan is the one guy in the country I wanted to exchange views with in a real dialogue – one that could potentially be among the most important conversations of this entire pandemic. After listening to his podcasts for a while now, I wanted to know: Was Joe simply a sower of doubt, a creator of chaos? Or was there something more? Was he asking questions that begged to be asked, fueled by necessary suspicion and skepticism?

Into the lion’s den

It wasn’t what Joe Rogan thinks that most interested me, it was how he thinks. That is what I really wanted to understand.

Truth is, I have always been a naturally skeptical person myself. One of my personal heroes, the physicist Edwin Hubble, said a scientist has a “healthy skepticism, suspended judgment and disciplined imagination, not only about other people’s ideas but also about their own.”

It’s a good way of thinking about the world – full of honesty and humility. I live by that, and I think Joe may to some extent as well. He will be the first to point out that he is not a doctor or a scientist who has studied these topics. Instead, he seems to see himself less a rapscallion and more of a sort of guardian of the galaxy, pointing out the missteps made by large institutions such as the government and mainstream medicine, and then wondering aloud if they can still be trusted to make recommendations or even mandates for the rest of us. To many, he represents a queen bee in a hive mind, advancing free will and personal liberty above all else.

The free will of your fist ends where my nose begins

When I said this to Joe, the MMA fighter, he paused, sat back and listened for a while. I asked him: Is it not possible to advocate strongly for personal freedoms, but also recognize the unique threat a highly contagious disease represents? He seemed to agree, but then quickly countered with a common misconception about the overall utility of the vaccines.

If vaccinated people transmit just as much as the unvaccinated, why are they really necessary?

It was like Joe and I were now in the octagon, circling one another. He stared at me intently now, eyebrows raised. I admitted that the vaccinated could still carry the virus at similar loads as the unvaccinated, but swiftly added – before he could claim victory – that there was more to the story.

I shared data with Joe showing the vaccinated were eight times less likely to become infected in the first place, and that their viral loads came down more rapidly if they did get infected – making them contagious for a shorter period and less likely to spread the virus.

Vaccines are not perfect, but he had to agree they are certainly a worthy tool to help control the spread of the virus. And, they are particularly effective at keeping people from getting severely ill or dying. They also may help prevent the development of long Covid, a chronic state of illness that some people develop after natural infection, even if their bout with the acute phase of infection was mild.

What he said next surprised me

So, it turns out that Joe Rogan nearly got vaccinated. That was a headline. It was a few months ago when he was in Las Vegas. He had an appointment scheduled but had logistical hurdles and couldn’t make it. He offered up this story as proof he is not necessarily “anti-vaccine,” even if he does consistently raise issues questioning their legitimacy.

It’s this sort of back and forth that makes it hard to pin Joe Rogan down, both in martial arts and a podcast interview.

For example: Even as he sometimes railed against masks, “The Joe Rogan Experience” masks emblazoned with his logo are available for sale on his website. I even bought one ahead of time and gave it to him as a gift. He looked surprised. (Incidentally, they are made in China.)

Despite a downplaying of Covid risks often heard on Joe’s podcast, his private studio prioritizes safety. A nurse was present to perform a rapid Covid test before we began. We were even checked for the presence of antibodies with a finger prick blood test.

Both of us carried antibodies – his from natural immunity, mine from the vaccine. I was vaccinated in December of last year and Rogan contracted Covid at the end of August. Even though this antibody test could only detect the presence of antibodies and not their strength, Joe took great pride in his test, insisting the thickness of his lines must mean stronger immunity. I am fairly certain he was joking. And, I didn’t have the heart to tell him that my antibody line was significantly thicker than his anyway.

The nuance of immunity

It bears repeating that no one should choose infection over vaccination. That is the concern many public health officials have had since the earliest days of the pandemic. If nothing else comes out of my conversation with Joe Rogan, I hope at least this point does. Far too many people have become severely ill and died, even after the effective vaccines became available. Just in the last three months, there have been more than 90,000 preventable Covid-19 deaths in the US among unvaccinated adults, according to a new analysis by the Kaiser Family Foundation.

At the same time, an Israeli study garnered a lot of attention after it appeared to show that natural immunity offered significant protection – even stronger than two doses of the Pfizer/BioNTech vaccine in people who had never been infected.”

So the question Joe raises, as do many others: Why should those who have previously had Covid still get the vaccine?

It’s a fair question, and one that I raised myself with Dr. Anthony Fauci back in early September. At the time, he told me there was no firm answer on this, and they were still looking into what the recommendations should be going forward and how durable natural immunity is in the long run.”

Part of the issue is that we still don’t have a clear idea of how many people have contracted Covid in the United States. The official number is around 45 million, but due to continued lack of sufficient testing, it remains uncertain. And many of the antibody tests that are currently available have high rates of both false negative and false positive results, oftentimes making them unreliable as proof of immunity.

Another issue with natural immunity is that it can vary substantially based on the age of the individual and just how sick they got in the first place. Milder illness in older people often resulted in fewer antibodies being produced.

Some studies have shown between 30 and 40 percent of people who have recovered from Covid did not have detectable neutralizing antibodies at all. That probably explains why a recent study showed that unvaccinated people who already had Covid were more than twice as likely to get reinfected as those who had also been vaccinated.

I told Joe that even in the study from Israel, the authors concluded with the recommendation that people who had recovered from Covid still get a vaccine. And when Joe pushed hard on the risk of myocarditis in kids who receive the vaccine, especially young boys, I countered back equally hard that the risk of myocarditis has been shown to be much higher for infected children under 16 years old compared to their uninfected peers. Those numbers dwarf the risk of myocarditis in kids who receive the vaccine (and, to be sure, most cases of myocarditis can be treated without hospitalization). For me, the risk-benefit analysis is clear: Vaccination is safer than infection.

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I guess a small part of me thought I might change Joe Rogan’s mind about vaccines. After this last exchange, I realized it was probably futile. His mind was made up, and there would always be plenty of misinformation out there neatly packaged to support his convictions. Truth is though, I am still glad I did it. My three-hour-long conversation wasn’t just with Rogan. If just a few of his listeners were convinced, it will have been well worth it.