It’s been more than four years since COVID-19 changed our lives, and scientists are still trying to figure out why this novel coronavirus makes some people so sick, and others never get it.
Take Geoffrey Bar Lev. He’s a social guy.
“I like to go dancing. I like to be with people. That's what I like,” said Bar Lev, who is 76.
That is how he hoped to spend his retirement. Then the pandemic happened. At his age, he was at high risk for severe disease or death if he became infected, so his social life stopped cold.
“I got accustomed to being alone. To not go out to eat often or not go to clubs and not go dancing. I got used to it,” he said. “Half of my living room, I turned into a gym. So I worked out a lot, and that's what kept me sane — working out.”
He followed guidance from the CDC. He got vaccinated. He got the boosters. He was careful about his nutrition. He took vitamins and added zinc, every day.
“I just didn't get it,” Bar Lev said.
He never got COVID-19.
“Almost everybody I know, everybody that I know has had it at least once,” Bar Lev said. “I suppose I was lucky because a lot of people had COVID here. A lot of people died because there were lots of anti-vaxxers here, and lots of people that didn't like wearing masks.”
“I thought that it was very serious,” he added.
Bar Lev is one of a small group of individuals known as NOVIDs.
“So, a NOVID is simply someone who has not had COVID,” according to Dr. Jan Patterson, a professor and infectious disease physician at UT Health San Antonio. She’s also an author and co-investigator at the San Antonio site of the RECOVER Initiative, a National Institutes of Health study with a mission to understand, treat, and prevent Long COVID.
“Of course, somebody who hasn't had it at all — that would usually be somebody who's had less exposure. Somebody who's not public facing, who doesn't have young children, you know, because young children, you know, tend to pass things around and they're often in little groups with other young children.”
A NOVID probably worked from home, and, like Bar Lev, generally avoided people.
Others may have had COVID and just don’t know it. Those are the people in which Jill Hollenbach is interested: People who’ve had COVID but never had a single symptom.
“We were really stringent in how we selected people. And so, we only included people that had no symptoms whatsoever,” she said.
Hollenbach is an epidemiology and biostatistics researcher at UCSF, and her lab has found a gene variant that appears to protect people … not from infection, but from symptoms.
It’s a variant of an immune system gene, HLA-B. HLA-B sits on the surface of all of our cells, looking for invaders. When it sees a virus, it snatches up a piece and holds it up so some of our fighter immune cells — T cells — can see it. Since the COVID virus was novel, the viral chunk would be unfamiliar to our T cells, so they wouldn’t do anything.
But in the people with this specific HLA gene variant, HLA-B*15:01, the t cells responded immediately … like they had seen the COVID virus before, even though that was impossible.
“We know that there is a lot of similarity between parts of the SARS-CoV-2 virus and common cold coronaviruses,” she said. “What we think is going on in this case is that it's just a very kind of happy accident that the way this piece looks when it's being held up to the T cells by [the HLA variant] B*15 is just really similar to how the common cold virus looks.”
The T cells thought the novel coronavirus was an old coronavirus they’d fought before. They thought it was a familiar enemy and fought it as such.
“And so, what we think is that very early in infection, these T cells get woken up, fired up, become activated and clear the infection before the person ever experiences any symptoms,” Hollenbach explained.
“So these people in some ways were vaccinated against COVID by virtue of having, you know, had a common cold virus earlier in their lives,” she added.
It’s important to learn why people like Bar Lev are NOVIDs — or became infected but never got sick — because a better understanding of our immune response to this virus could help us more efficiently fight the next virus … or fungus, or bacteria. That might reduce the need for distance and isolation. Bar Lev hopes that never has to happen again.
“It really cuts into a person's life,” he mused. “A long way. It really cuts deep. It's just a difficult, lonely existence.”
In the meantime, Bar Lev remains COVID cautious, generally avoiding large crowds and keeping up to date on his vaccines. It may be a lonely existence, but he still doesn’t know how he’d respond to COVID if he became infected. Would he become very sick? Would he die? That’s not a risk he’s willing to take.
