It deserves a wow. Some 57% of the human population has received at least one dose of the Covid-19 vaccine, and 45% are fully vaccinated, in less than a year.

This means the vaccine has spread approximately twice as fast as the virus, never mind that the virus itself is an exceptionally fast spreader that organizes its own distribution without help from trained administrators and sub-zero storage.

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Pfizer Covid-19 vaccines at a Dallas County Health and Human Services drive up vaccination site in Mesquite, Texas, Nov. 30.

Photo: LM Otero/Associated Press

It deserves a wow. Some 57% of the human population has received at least one dose of the Covid-19 vaccine, and 45% are fully vaccinated, in less than a year.

This means the vaccine has spread approximately twice as fast as the virus, never mind that the virus itself is an exceptionally fast spreader that organizes its own distribution without help from trained administrators and sub-zero storage.

Add that infection also offers a kind of vaccination, so now two kinds of resistance to Covid-19 have been spreading with unprecedented rapidity through the human population.

Numerous were the complaints about how Delta spoiled the summer even for vaccinated people, but it’s not clear why this was so. Vaccination takes away Covid’s deadliest property, its novelty to the human immune system, turning it into the equivalent of a cold or flu. Nobody lets the prospect of a cold or flu spoil their holiday (though perhaps they should for the sake of their elderly in-laws).

The point is not frivolous. It suggests why, rather than a dark new chapter, the Omicron variant may be our last big wallow in hysteria, from which we will awake slightly red-faced in the morning.

Start with numbers and remind yourself that what turned Covid into a global catastrophe wasn’t its unusual deadliness—in unvaccinated people, it appears to be roughly twice as deadly as the flu when unvaccinated apples are compared to unvaccinated apples; in vaccinated people it appears to be significantly less deadly given that our standard flu mortality estimate of 0.1% arises in a U.S. population in which vaccination approaches 70% for the riskiest age brackets.

The big disturber of our equanimity was Covid’s rapid spread—with so many of us getting our high-risk first exposure in a compressed period of time, straining the world’s hospitals.

With flu, the U.S. government estimates that 5% to 20% of us (with or without symptoms) are infected each year; about half of us are vaccinated. With Covid, a government-sponsored study recently estimated that 100 million were infected in 2020, or 30% of the U.S. population, at a time when almost nobody was vaccinated.

This speed of transmission is what keeps throwing the world for a loop; moreover, it seems indisputable in retrospect that we squandered our best point of leverage by failing to focus on protecting the elderly and those at highest risk.

Indeed, so much of what we became hysterical about—mask wearing and vaccine hesitancy as applied to the low-risk—was a poor substitute for communicating about and acting on distinctions in risk.

The worst part is we knew better on day one, but political imperative did not favor realistic communication about risk or prioritization.

Maybe the last of these pointless battles is the current ideologized argument over whether the vaccinated contribute significantly to transmission. The science is inconclusive, but a vaccinated person with Delta might be far less infectious than an unvaccinated person with Delta and still about as infectious as an unvaccinated person with the original Wuhan variant, which had no trouble circling the globe.

In any case, the bigger factor now is behavior, with social distancing falling by the wayside for an increasingly low-risk population. It’s clearer than ever that few of us will escape infection regardless of vaccination status. An extraordinarily safe assumption is that a more communicable variant, if that’s what Omicron is, won’t be “contained.” Hand-wringing about whether Omicron should have been identified sooner seems a tad unrealistic when ever-advancing immunity (natural and vaccinated) guarantees that a huge majority of infections will elude detection among millions of mild colds and flus or when devoid of symptoms altogether.

In such a world, the idea that everybody’s vaccination status is everybody else’s business rests on increasingly forlorn assumptions. The shrinking number of Americans who are both high-risk and unvaccinated may be fools but the consequences fall mostly on themselves.

A second blessing is that evolution gives the virus a reason to become less deadly and disabling, rather than the opposite, though we can never rule out bad luck. In recent weeks, meanwhile, I can’t help but notice the media finally noticing the dead end China set for itself. The Chinese people are falling behind the world in acquiring the powerful hybrid immunity that comes from effective vaccines plus exposure to the evolving virus.

Beijing started out with few good options but would have been wise to throw in its lot with the West on vaccine development. Now its slowly souring bet on zero Covid can only further alienate the country from a world that won’t soon be forgetting where this plague originated.

Wonder Land: What we needed most from the Government during Covid's two long years were mid-course corrections. Instead politicians chose rigidity, such as Joe Biden's vaccine mandate. Images: AFP via Getty Images Composite: Mark Kelly The Wall Street Journal Interactive Edition