Experts say BA.2 could be more of a 'bump' than a surge. Is this the future of COVID?
Is America about to dodge the BA.2 bullet?
For weeks now, BA.2 — an even more transmissible subvariant of BA.1, the original, hypercontagious Omicron strain — has been wreaking havoc across Europe, triggering steep and sudden resurgences of infection just as the continent's enormous winter wave finally seemed to be subsiding. In England, COVID-19 hospitalizations haven’t been higher since the pre-vaccine era.
At first, the fear was that BA.2 would spark a similar U.S. surge. But dig into the latest data, and it looks like something different might be happening instead: a less dangerous and disruptive type of COVID “bump” that could foreshadow the next phase of the pandemic — if America is lucky.
There’s no question that U.S. cases are rising, 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 detected in 55% of COVID-19 samples analyzed between March 20 and 26.
As a result, average case counts have climbed over the last two weeks, notably in Washington, D.C. (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 this spring in other cities and states as well.
But it would be a surprise, at this point, if BA.2 spiked in the U.S. the way Omicron BA.1 spiked over the winter — or the way BA.2 recently spiked in Europe.
There are a few reasons for this. The first is that BA.2 is already moving too slowly to cause that kind of U.S. surge. Right now, the CDC estimates that the newer subvariant, which has been spreading since December, accounts for at least 72% of new COVID cases nationwide. The day Omicron BA.1 hit 73% nationally — Dec. 20 — America recorded 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 U.S. is recording fewer PCR test results now than it was then, in large part because at-home antigen tests — which usually go unreported — are more widely available. “A lot of people are rapid-testing positive for mild cases of COVID, staying home for a few days, getting better, and getting on with life,” the Atlantic’s Derek Thompson noted Thursday. “This cycle makes no contact [with] official data.” Thompson called it “an invisible wave.”
He's right that PCR numbers — the ones that register on COVID tracking sites — are down. Back on Dec. 20, America was averaging more than 1.7 million of these tests per day; now it’s averaging about half as many (870,000).
But just because the full extent of the virus’s spread is unclear doesn’t mean its trajectory is unknowable. The U.S. has never detected every single infection through testing. Instead, officials rely on the percentage of tests coming back positive at any given moment to assess the rate of transmission.
On Dec. 20, this positivity rate was nearly 8% nationally. Today, it’s less than half that number: 3.5%.
Meanwhile, in New York — which is widely seen as America’s BA.2 bellwether — the current positivity rate is even lower, at just 3%. To be sure, that’s up from a low of 1.5% in early March. But it’s nothing like the astronomical increase 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 is causing cases to go up. It will continue to cause cases to go up across different regions. But it’s starting from a much lower level than Omicron BA.1 while also transmitting less rapidly and readily — which means, as Yale epidemiologist Nathan Grubaugh recently put it, that “we are NOT in for a sharp increase in cases or a big wave (at least at the current rates).”
Why? Because waves (or surges or bumps) don’t rise forever, but rather peak at a fairly predictable pace. That’s what’s happening across Europe, where BA.2 infections are already in decline; it’s also what’s happening in Canada.
And in fact, a similar pattern may already be emerging in New York City, according to COVID researcher Conor Kelly. Kelly recently calculated that while cases there have been growing week over week since early February, the rate at which they’ve been growing peaked in late March and has already started to come down — all while hospitalizations have remained nearly flat.
This suggests that local cases could soon top out at a fraction of their winter Omicron heights, with little of the severe disease and death that accompanied that harrowing surge. “Things are not running out of control,” Kelly explained. “No need for anyone to panic in the slightest 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 COVID” looms as a real concern. Millions of seniors remain unvaccinated; tens of millions more remain unboosted. Even if BA.2 doesn’t spark another massive wave, it still poses the same individual risk to one's health as Omicron BA.1. People should be fully up to date on vaccination and should exercise caution in congregate settings.
At the same time, the vulnerable can no longer rely on indoor mask mandates to help shield 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 surveillance, therapeutics, boosters and next-generation vaccines — all meant to prepare America for new variants and future surges — may never survive the deeply partisan Senate. That is an unforced error Americans could soon come to regret.
But even as critics lament the country’s first “So What? Surge,” as the Atlantic’s Katherine J. Wu recently dubbed it — and how “poorly positioned” the U.S. is to meet the next serious outbreak — it’s also worth reflecting on the hard-won but undeniable progress a BA.2 non-wave could represent.
No one is exactly sure why BA.2 doesn’t seem like it will hammer the U.S. nearly as hard as, say, the U.K. Warming weather might play a part; last winter, the Alpha variant slammed England, then spluttered in the 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 mostly prevent its BA.2 sister lineage from immediately reinfecting the same person. (Vaccination and boosters are extraordinarily good at blocking severe disease and death, and they help shield against infection as well.)
At a meeting of the Food and Drug Administration advisory board earlier this week, leading virologist Trevor Bedford of Seattle’s Fred Hutchinson Center estimated that a staggering 50% of Americans had been infected by Omicron in the previous 10 weeks. Enabled by lagging vaccination rates and lapsing mitigation measures, those infections came at a horrific, unacceptable cost: another 200,000 Americans dead since early December.
But they also seem to help shield those who were fortunate enough to survive from the worst of BA.2, and to hinder spread in a way that much of Europe lacks (perhaps due to lower BA.1 exposure and a more sudden shift away from safety measures).
If that’s the case, America’s BA.2 bump — with people “rapid-testing positive for mild cases of COVID, staying home for a few days, getting better, and getting on with life,” as the Atlantic’s Thompson put it — could be another step toward the pandemic’s “next normal.”
According to Bedford, there are two plausible scenarios for the next year: (1) another “Omicron-like emergence event” in which a “new wildly divergent virus” evades existing immunity and upends society all over again, or (2) “evolution within BA.2” to “further increase intrinsic transmission,” causing “lower attack rates” largely “driven by drift + waning [immunity] + seasonality.”
He considers the second “more likely” — suggesting that future surges might look more like BA.2 than BA.1.
Fingers crossed, then. 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 Commerce Secretary Gina Raimondo, to catch what is almost certainly BA.2 after attending Saturday’s annual Gridiron Dinner or coming into close contact with someone who was there. So far Pelosi is “asymptomatic,” according to her spokesperson, and no one connected to the event has gotten seriously ill.
In recent weeks, many Americans who have been mostly cautious for the last two years — like Pelosi — have been removing their masks and gathering indoors. Many of them will encounter BA.2 this spring; Gridiron-style outbreaks won’t be uncommon. But unless current trends change dramatically, this probably won’t herald another terrifying surge. Instead, it may signal a more welcome development: a time when “living with the virus” stops being a way to deny reality and finally starts being realistic.
