Experts say BA.2 could be more of a “bump” than a rise. Is this the future of COVID?

Is America about to dodge the BA.2 bullet?

BA.2 – an even more transmissible sub-variant of BA.1, the original hyper-infectious Omicron strain – has been wreaking havoc across Europe for weeks, with a precipitous and sudden resurgence of infection, much like the continent’s massive winter wave finally seemed to be. diminishing. In England, COVID-19 hospital admissions have not been higher since the pre-vaccination era

Initially, the fear was that BA.2 would trigger a similar US rise. But delve into the latest data and it seems that something else is going on instead: a less dangerous and disruptive type of COVID “bump” that could predict the next phase of the pandemic — if America is lucky.

A sign on a city street reads: COVID Test Site.

A COVID-19 testing site in Manhattan on March 31. (Spencer Platt/Getty Images)

There is no doubt that US business is on the rise, or that BA.2 is responsible. Last week the Centers for Disease Control and Prevention announced that the new variant had officially achieved nationwide dominance after it was discovered in 55% of the COVID-19 samples analyzed between March 20 and 26.

As a result, the average number of cases has risen in the past two weeks, particularly in Washington, DC (106%) and New York (58%) — some of the first places BA.2 landed. It won’t be a surprise if the same pattern plays out in other cities and states this spring.

But it would be a surprise at this point if BA.2 peaked in the US the way Omicron BA.1 peaked in the winter — or the way BA.2 peaked recently in Europe.

Here are a few reasons for this. The first is that BA.2 is moving too slowly to create such an American wave. At present, the CDC estimates that the newer subvariant, which has been spreading since December, is responsible for at least 72% of new COVID cases rural. The day Omicron BA.1 hit 73% nationally – December 20 – America registered 300,000 cases. The curve was already a vertical line. Today, that number is 10 times lower, at about 30,000.

Some observers have noted that the US now records fewer PCR test results than it did then, in large part because home antigen tests — which usually go unreported — are more widely available. “Many people quickly test positive for mild cases of COVID, stay at home for a few days, get better, and go on living,” says Atlantic’s Derek Thompson. noted Thursday. “This cycle is not making contact” [with] official data.” Thompson called it “an invisible wave.”

A medical worker is seen through the window of a PCR analysis machine.

Medical Technologist Lisa Bates in the PCR test lab at Quest Diagnostics in Indianapolis. (Jon Cherry/Getty Images)

He’s right that the PCR numbers — the ones that register on COVID tracking sites — aren’t available. On December 20, America was doing an average of more than 1.7 million of these tests per day; now it averages about half the number (870,000).

But just because the full extent of the spread of the virus is unclear, does not mean it is procedure is unknowable. The US has never detected every infection through testing. Instead, officials rely on the percentage of tests that come back positive at any given time to judge transfer speed.

On December 20, this positivity rate nationwide was almost 8%. Today that is less than half: 3.5%.

Meanwhile, in New York – widely regarded as America’s BA.2 bellwether – the current positivity rate is even lower, at only 3%† Sure, that’s up from a 1.5% low in early March. But it’s nothing like the astronomical rise from 5% to 22% that the state experienced after Omicron BA.1 exploded in early December.

And that’s the point: BA.2 is spreading. It causes the number of cases to rise. It will cause the number of cases to increase in different regions. But it starts at a much lower level than Omicron BA.1 and also transmits less quickly and easily — meaning, as Yale epidemiologist Nathan Grubaugh put it recently, “we are NOT going to see a sharp increase in the number of cases or a big wave ( at least at current rates).

Why? Because waves (or waves or bumps) don’t rise forever, but rather peaks at a fairly predictable pace† That’s what’s happening all over Europe, where there are BA.2 infections already in disrepair† it’s also what happens in Canada

People queue outside a COVID testing site.

People queue at a COVID-19 testing center in Toronto. (Geoff Robins/AFP via Getty Images)

And according to COVID researcher Conor Kelly, a similar pattern may emerge even in New York City. Kelly recently calculated that while cases have increased week after week since early February, the rate what they grew on peaked at the end of March and is already starting to decline – all this time hospital admissions have remained virtually the same

This suggests that local cases could quickly peak at a fraction of their winter Omicron height, with little of the severe illness and death associated with that harrowing wave. “It’s not getting out of hand,” Kelly explains. “Nobody needs to panic in the least about BA.2, in my opinion.”

None, which means the pandemic is over† An estimated 7 million Americans are immunocompromised, no children under 5 have been vaccinated, and “long-term COVID” looms as a real concern. Millions of seniors remain unvaccinated; tens of millions more remain untouched. Even if BA.2 doesn’t create another huge wave, it stays the same individual health risk as Omicron BA.1. People should be fully aware of vaccination and exercise caution in communal settings.

At the same time, the vulnerable can no longer rely on indoor mask mandates to protect them from exposure. When it comes to being careful, Americans are now pretty much on their own. And the Biden administration’s modest request for a $10 billion federal investment in next-generation surveillance, therapies, boosters and vaccines — all designed to prepare America for new variants and future increases — the deeply partisan senate may never survive† that’s a casual mistake Americans could soon regret

President Biden.

President Biden speaks on April 1 (Anna Moneymaker/Getty Images)

But even as critics complain about the first ‘So What? Surge’, as Katherine J. Wu . from the Atlantic Ocean dubbed it recently — and how “poorly positioned” the US is to face the next serious outbreak — it’s also worth thinking about the hard-won but undeniable progress a BA.2 non-wave could mean.

No one is exactly sure Why BA.2 doesn’t seem to hit the US as hard as, say, the UK. Warming of the weather could play a role; last winter, the Alpha variant hit England and then sputtered into the United States. But the strongest theories have to do with immunity — or, more precisely, the fresh antibodies produced by a recent Omicron BA.1 infection, which are usually prevent his BA.2 sibling line to immediately reinfect the same person. (Vaccination and boosters are extremely good at blocking serious illness and death, as well as protecting against infection.)

At a meeting of the Food and Drug Administration’s advisory board earlier this week, leading virologist Trevor Bedford of the Fred Hutchinson Center in Seattle said estimates that as many as 50% of Americans had been infected by Omicron in the past 10 weeks. Thanks to lagging vaccination rates and expiring mitigation measures, those infections came at a horrific, unacceptable cost: An additional 200,000 Americans have died since early December.

But they also seem to help protect those lucky enough to survive the worst of BA.2 and stop the spread in a way much of Europe doesn’t (perhaps due to lower exposure to BA.1 and a more sudden shift in security measures).

If that’s the case, the US BA.2 bump — with people “quickly testing positive for mild cases of COVID, staying home for a few days, getting well and getting on with life,” as Atlantic’s Thompson puts it , are another step towards the pandemic”next normal

iHealth COVID-19 test kits in a USPS envelope.

Free iHealth COVID-19 At-Home Antigen Tests Sent by the Federal Government. (Justin Sullivan/Getty Images)

according to Bedfordthere are two plausible scenarios for the next year: (1) another “Omicron-like emergence” in which a “new, wildly diverse virus” evades existing immunity and turns society upside down again, or (2) “evolution within BA.2” to “further increase intrinsic transmission”, making “lower attack rates” largely “drift + decreasing” [immunity] + seasonality.”

He considers the second “more likely” – suggesting that future peaks are more like BA.2 than BA.1.

So fingers crossed. On Thursday, House speaker Nancy Pelosi announced she had tested positive for COVID-19 – the latest in a growing number of prominent Washington figures, including Attorney General Merrick Garland and Secretary of Commerce Gina Raimondo, to catch what is almost certainly BA.2 after attending Saturday’s annual Gridiron dinner or come into close contact with someone who was there. So far, Pelosi is “asymptomatic,” according to her spokesman, and no one involved in the event has fallen seriously ill.

In recent weeks, many Americans who have been especially cautious over the past two years — like Pelosi — have removed their masks and gathered indoors. Many of them will encounter BA.2 this spring; Gridiron-like outbreaks will not be uncommon. But unless current trends change drastically, it probably won’t usher in another terrifying wave. Instead, it could indicate a more welcome development: a time when “living with the virus” is no longer a way of denying reality and is finally starting to become realistic.

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