Omicron effect: We’ll all have some immunity to Covid-19 soon

The ranks of “immunologically naive” will be awfully small once the omicron wave subsides, and that will require a new reckoning on what make sense.

As Covid-19’s omicron wave begins to subside, one thing seems pretty clear: After it has passed, the number of Americans who are still immunologically naive to Covid-19 — that is, they’ve been neither infected by it nor vaccinated against it — will be quite small.

The end of immunological naivete to Covid in the U.S. should change how we think about the disease and what policies we put in place to manage it.

How small? By my rough estimate, 1.8% of Americans, about six million people, will remain untouched by either vaccines or Covid a month or two from now. I arrived at this by taking the covidestim.org estimates of cumulative U.S. Covid-19 infections through Jan. 19 (257.5 million) and the Centers for Disease Control and Prevention’s estimate of how many Americans are fully vaccinated against Covid (209.5 million) and making several somewhat dodgy assumptions, so I wouldn’t take the exact percentage too seriously.(1) But it’s clearly not a whole lot of people.

This doesn’t mean the coast will be clear after, say, February. Some new variant could upend everyone’s calculations just as delta and omicron did, and even endemic Covid will still be deadly for many. In October, before omicron, computational biologist Trevor Bedford of the Fred Hutchinson Cancer Research Center in Seattle set out to model what Covid’s toll in the U.S. would be after everybody over age three had been exposed or vaccinated. His estimate: 40,000 to 100,000 deaths a year, somewhat worse than seasonal influenza, though in the same ballpark.

Still, as lots of people pointed out back in the spring of 2020 in the process of wildly underestimating the threat posed by Covid-19, we don’t shut down the country for seasonal influenza. The end of immunological naivete to Covid in the U.S. should change how we think about the disease and what policies we put in place to manage it.

Some of the most obvious changes have to do with vaccination. There was a lot of talk last year, some of it from President Joe Biden, about how Covid-19 had become a “pandemic of the unvaccinated.” There was some truth to this: from April through early October, according to the CDC, 79% of Covid deaths for which vaccination status was available — and 92% for those younger than 65 — were among the unvaccinated.

“Pandemic of the immunologically naive” would have been more accurate, though. A CDC study released this week found that while those who had been neither vaccinated nor previously infected with Covid-19 were by far the most vulnerable to contracting and being hospitalized with the delta variant last summer and fall, prior infection actually appeared to be more protective than vaccination. An earlier CDC study had found the opposite result with pre-delta Covid, and Bloomberg Intelligence analyst Sam Fazeli says (terminal only, sorry) there’s emerging evidence that vaccines protect better against severe omicron outcomes than prior infection does. But both clearly confer significant immunity, and once virtually everyone in the U.S. has one or the other or both, going to great lengths to differentiate the unvaccinated from the vaccinated makes a lot less sense.

The tricky bit here is that encouraging vaccination will remain very important. I’m no epidemiologist or immunologist or ologist of any other kind, but I have become sadly familiar with U.S. and foreign mortality data over the past 22 months and one thing that has stood out in the numbers lately is how easy it is to find evidence of the Covid vaccines’ life-saving impact even when one isn’t really looking for it. The vaccines developed so far, while less effective at preventing transmission with each new variant, have been spectacularly effective at preventing severe disease and death — by the reckoning of the Commonwealth Fund they saved 1.1 million lives in the U.S. through November. Getting boosters and updated vaccines into arms will be crucial to keeping down the toll of endemic Covid as immunity from past vaccines and infections fades. If scientists come up with an effective pan-coronavirus vaccine that shuts down the virus entirely, something my Bloomberg Opinion colleague Lisa Jarvis just wrote about, maybe we can even push Covid from endemic to rare.

In the meantime, though, requiring restaurant guests or theatergoers to provide evidence of vaccination — which I was a big fan of this fall in New York City, as it made me and a lot of other people more comfortable with going out — starts feeling more like airport-style security theater than a useful public health measure. As for employer vaccine mandates, they succeeded last year in getting lots of people vaccinated and thus saving lots of lives, and will continue to make sense in some sectors. But most of the low-hanging fruit from that approach has already been harvested, especially now that the U.S. Supreme Court has nixed the president’s plan to impose mandates on the private sector. Keeping Kyrie Irving from playing home games for the Brooklyn Nets isn’t protecting anyone at this point, and I find it awfully hard to imagine that it’s persuading anyone to get vaccinated.

I cringe a little at saying all this because of the rejoicing that any relaxation of vaccination rules will occasion among the grifters who have scared millions of Americans away from getting life-saving shots. But that can’t be a reason not to say it. While trying to persuade people to get vaccinated should remain a priority, sequestering the unvaccinated minority from the rest of us really shouldn’t. Despite having arrived via different routes, one far more dangerous than the other, we are, for now, all in more or less the same boat.More From Other Writers at Bloomberg Opinion:

• What It Will Take to Vaccinate the World: Clara Ferreira Marques
• A Vaccine to Prevent All Covid Is Within Reach: Lisa Jarvis
• Yes, We May All Get Covid, But Timing Is Everything: Faye Flam

(1) There have been 58.1 million new infections since the beginning of December, according to covidestim.org, so I assumed that there will be 58.1 million more, bringing the total to 315.7 million, or 96% of the U.S. population. I multiplied that times 122.4 million not fully vaccinated Americans and added the result to the fully vaccinated total, which got me to 325.9 million out of the country's estimated mid-2021 population of 331.9 million. What's dodgy? The estimates provided bycovidestim.org, a Harvard-Stanford-Yale joint venture, could be too high or too low and may be especially unreliable now because omicron so completely overwhelmed the country's testing capacity. Theydefinitely double-count some individuals, since lots of omicron infections in particular have been second infections. On the other hand, the CDC's fully vaccinated number is widely acknowledged to be an undercount, and unvaccinated people are more likely to have been infected with Covid than the population as a whole, so some of the errors may cancel each other out.

This column does not necessarily reflect the opinion of the editorial board or Bloomberg LP and its owners.

Justin Fox is a Bloomberg Opinion columnist covering business. He was the editorial director of Harvard Business Review and wrote for Time, Fortune and American Banker. He is the author of “The Myth of the Rational Market.”