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Two and a half years and billions of estimated infections into this pandemic, SARS-CoV-2’s visit has clearly turned into a permanent stay.

Experts knew from early on that, for almost everyone, infection with this coronavirus would be inevitable.

As James Hamblin memorably put it back in February 2020, “You’re Likely to Get the Coronavirus.”

But now, as wave after wave continues to pummel the globe, a grimmer reality is playing out.

You’re not just likely to get the coronavirus. You’re likely to get it again and again and again.

“I personally know several individuals who have had COVID in almost every wave,” says Salim Abdool Karim, a clinical infectious-diseases epidemiologist and the director of the Center for the AIDS Program of Research in South Africa, which has experienced five meticulously tracked surges, and where just one-third of the population is vaccinated.

Experts doubt that clip of reinfection—several times a year—will continue over the long term, given the continued ratcheting up of immunity and the potential slowdown of variant emergence.

But a more sluggish rate would still lead to lots of comeback cases.

Aubree Gordon, an epidemiologist at the University of Michigan, told me that her best guess for the future has the virus infiltrating each of us, on average, every three years or so.

“Barring some intervention that really changes the landscape,” she said, “we will all get SARS-CoV-2 multiple times in our life.”

If Gordon is right about this thrice(ish)-per-decade pace, that would be on par with what we experience with flu viruses, which scientists estimate hit us about every two to five years, less often in adulthood.

It also matches up well with the documented cadence of the four other coronaviruses that seasonally trouble humans, and cause common colds.

Should SARS-CoV-2 join this mix of microbes that irk us on an intermittent schedule, we might not have to worry much.

The fact that colds, flus, and stomach bugs routinely reinfect hasn’t shredded the social fabric.

“For large portions of the population, this is an inconvenience,” Paul Thomas, an immunologist at St. Jude Children’s Research Hospital, in Tennessee, told me.

Perhaps, as several experts have posited since the pandemic’s early days, SARS-CoV-2 will just become the fifth cold-causing coronavirus.

Or maybe not.

This virus seems capable of tangling into just about every tissue in the body, affecting organs such as the heart, brain, liver, kidneys, and gut; it has already claimed the lives of millions, while saddling countless others with symptoms that can linger for months or years.

Experts think the typical SARS-CoV-2 infection is likely to get less dangerous, as population immunity builds and broadens. But considering our current baseline, “less dangerous” could still be terrible—and it’s not clear exactly where we’re headed.

When it comes to reinfection, we “just don’t know enough,” says Emily Landon, an infectious-disease physician at the University of Chicago.

For now, every infection, and every subsequent reinfection, remains a toss of the dice.

“Really, it’s a gamble,” says Ziyad Al-Aly, a clinical epidemiologist and long-COVID researcher at Washington University in St. Louis.

Vaccination and infection-induced immunity may load the dice against landing on severe disease, but that danger will never go away completely, and scientists don’t yet know what happens to people who contract “mild” COVID over and over again.

Bouts of illness may well be tempered over time, but multiple exposures could still re-up some of the same risks as before—or even synergize to exact a cumulative toll.

“Will reinfection be really bad, or not a big deal?

I think you could fall down on either side,” says Vineet Menachery, a coronavirologist at the University of Texas Medical Branch.

“There’s still a lot of gray.” Continue reading

• Katherine J. Wu is a staff writer at The Atlantic. She holds a Ph.D. in microbiology from Harvard University.

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