The Washington PostDemocracy Dies in Darkness

Opinion Half-measures won’t protect us from the new covid-19 variant

British Prime Minister Boris Johnson in London on Monday. (Tolga Akmen/AP)

As bad as covid-19 has been, you can imagine it being worse. What if each sick person had infected an average of 15 others, as measles does, rather than two or three? What if it had killed more young people than old people, like the 1918 influenza? Or simply killed a much higher percentage of its victims — 10 percent, like SARS, or 34 percent, like MERS?

If we ever run into such a bug, covid-19 may prove to have been our training exercise, preparing us for the next round just as SARS prepared the Pacific Rim to weather covid-19 with relative aplomb. Maybe next time, the rest of us will also be ready to take decisive action before the new pathogen can get a foothold.

It’s a nice theory, but like any theory, it needs a real-world test. Unfortunately, we might be getting one as London goes into lockdown and as nation after nation closes its borders to British travelers. All because a new variant of the coronavirus, now common in Southeast England, may be as much as 70 percent more contagious — possibly by reinfecting people who already had a different variant of the coronavirus.

Though that’s far from the most likely scenario, if the worst came true, it would obviously complicate our hopes of reaching herd immunity in 2021 through some combination of vaccination and natural infections. In the meantime, it complicates life for officials who undoubtedly wish they could go back to January and close their borders, limit internal movement, test the hell out of their population and quarantine the sick.

It’s pleasant to wish yourself back there with them, then spin forward to a world where America was like Australia, with perhaps occasional lockdowns but longer stretches of relative normalcy. Eventually, though, you come back to the reality where they didn’t act more forcefully, and wonder whether they ever really could have.

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For those precautions to work, most countries needed to take them before they could be sure they were necessary. Leave aside the economic and political costs; if countries do that too often, many alarms will prove false, and authorities will quickly become the boys and girls who cried wolf. When a real threat does arrive, their cries for public action will go unanswered.

Full coverage of the coronavirus pandemic

There’s even the uncomfortable possibility this has already happened, because of the peculiarities of covid-19. The disease fell into an uncanny perceptual valley — deadly enough to kill perhaps 1 million Americans if everyone went about their lives as usual, yet not deadly enough to make the tradeoff between normal life and normal mortality rates seem overwhelmingly obvious. What if the cycle of under- and over-reaction, rather than training us to respond better to a more dire disease, ends up priming us to ignore emerging threats even more thoroughly — or at least, enough of us to make pandemic control effectively impossible?

I’m sure world leaders wonder about this too, which raises the stakes even further on sounding a false alarm. As a columnist, I’m supposed to confidently offer a solution to their quandary: Do this, not that. But I can’t tell them whether the apparently elevated infectiousness is real or just the kind of statistical mirage that popped up so frequently last spring. All I can do is suggest they avoid repeating one particularly spring folly: thinking a binary uncertainty — here or not, bad or not — can somehow be resolved by compromising on half-measures. A partial response that breeds either complaceny or resentment might be worse than nothing.

The current bans on British travelers, for example, are all too reminiscent of America closing her border to China while the virus changed planes in Italy. The new variant of virus in Britain is already known to be in other countries, and we should assume the same of a South African variant that reportedly may cause more serious illness in young people. If you think these new variants are bad enough to warrant travel restrictions, then you should probably keep everyone out, as Israel will do starting Wednesday, rather than messing with targeted half-measures.

That won’t keep the new variants at bay if they’re already inside your borders, but by preventing new introductions, it might keep them rare enough to control through testing and contact tracing — especially if governments also drastically step up capacities for testing, contact tracing and genetic surveillance of variants. Of course, if the new variants turn out to be nothing, that will be a very expensive and highly counterproductive overreaction. But in that case, why halt flights from Britain? All you’re doing is spending reputational capital you may need later.

I’m well aware that neither option is precisely attractive, and I wish I were more sure which is the right course. Or less sure that, whatever the right answer should be, many countries will fail to give it should this turn out to be covid-19’s final exam.

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Coronavirus: What you need to know

Where do things stand? See the latest covid numbers in the U.S. and across the world. In the U.S., pandemic trends have shifted and now White people are more likely to die from covid than Black people.

The state of public health: Conservative and libertarian forces have defanged much of the nation’s public health system through legislation and litigation as the world staggers into the fourth year of covid.

Grief and the pandemic: A Washington Post reporter covered the coronavirus — and then endured the death of her mother from covid-19. She offers a window into grief and resilience.

Would we shut down again? What will the United States do the next time a deadly virus comes knocking on the door?

Vaccines: The CDC recommends that everyone age 5 and older get an updated covid booster shot. New federal data shows adults who received the updated shots cut their risk of being hospitalized with covid-19 by 50 percent. Here’s guidance on when you should get the omicron booster and how vaccine efficacy could be affected by your prior infections.

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