What the hell is going on with COVID right now?
Amid the chaos and controversy that followed a federal judge’s decision to overturn the US travel mask mandate earlier this week — a decision that the Justice Department is now appealing — it was easy to d Forgetting the fact that the mask policy wasn’t the only thing is getting more perplexing by the day.
The pandemic itself has probably never been so difficult to analyze.
For one thing, cases have spiked in 41 states over the past two weeks, pulled from their post-Omicron lows by an even more transmissible subvariant called BA.2.
On the other hand, BA.2 has been dominant in the United States for about a month – and cases are increasing about a tenth as fast as they were in the first month of Omicron’s reign, increasing by 46% between on March 20 and April 20 compared to with 475% between December 15 and January 15.
Then again, the United States is only reporting around 900,000 tests per day, on average – a fraction of the 2.5 million recorded at Omicron’s peak. As Americans shift to rapid home testing, or not bother testing at all, we are undercount infections more than before.
Yet hospitalizations recently hit a low of around 15,000 and have barely budged for weeks, while the number of intensive care units has plummeted. lowest level since the start of the pandemic – another stark contrast to winter, when hospitalizations more than doubled between December 20 and January 20 to a record high of 160,000.
This could be a sign, some experts say, that infection- and vaccine-induced immunity is mitigating the most dire effects of the latest variants, a development they hope will usher in a less dangerous and disruptive phase of the pandemic. .
Or, as other experts argue, it could just be the usual lag between cases and hospitalizations.
Like we said: a confusing moment. So rather than predicting the future — never a wise move with the SARS-CoV-2 virus — here are three different ways it could play out in the weeks and months ahead.
The worst case scenario
In recent days, it’s become clear that BA.2, which has been slowly spreading across the US since December, isn’t the only sub-variant in town anymore. It’s also not the best fit. Instead, BA.2.12.1 – a sub-variant of a sub-variant – now appears to outperform its predecessor in flagship states such as New York and Massachusetts.
According to the Centers for Disease Control and Prevention’s varying proportions estimates, BA.2 has accounted for more than 70% of infections in the United States since early April. But its growth stabilized there. Meanwhile, BA.2.12.1 has gone from just 3.3% of infections at the end of March to 19% by April 16.
In other words, BA.2.12.1’s share of cases practically doubled every week – 2.5 times faster than BA.2’s. This involves a significanttransmission advantage“says Dr. Eric Topol, director of the Scripps Research Translational Institute – an institute that is”similar in magnitude to the observed advantage of BA.2 over BA.1“, according to Trevor Bedford, chief virologist at the Fred Hutchinson Center in Seattle.
“The BA.2 wave in the United States is… in the process of metamorphosis [in]to wave BA2.12.1”, Topol recently tweeted.
Why? Probably because BA.2.12.1 has an additional spike protein mutation (L452Q) which, in a slightly different form (L452R), “appeared to have an important role in promoting the spread of [the] Delta variant,” according to Bedford.
Meanwhile, the same mutation BA.4 and BA.5 sublines are spreading rapidly in South Africa.
“The hypothesis is then that 452R/Q confers an additional intrinsic transmission advantage”, Bedford has explained. “Looking to the future, I expect these 452R/Q sublines to continue to grow.” The question is how much damage they do as they spread. The main reason why BA.2 has evolved much slower than Omicron BA.1 in the United States is that a huge percentage of the population – up to half – have just had Omicron BA.1, which confers a degree of immunity against reinfection. If BA.2.12.1 (and BA.4, BA.5) can circumvent some of this immunity, it could turn the current ripple of cases into more than one wave. And while vaccines and especially boosters have so far shown an extraordinary ability to protect recipients from serious illness and death, millions of older people remain unvaccinated and/or unboosted; long COVID looms as a real concern; and it is still unclear how much immunity wanes over time.
The worst-case scenario, then, is for these new sublines to exploit continued US vulnerabilities — including a steady decline in masking — and trigger more severe disease than BA.2 alone.
The best scenario
The good news is that there are no signs – yet – of anything in the United States approaching previous waves of hospitalizations and deaths.
National numbers (which, again, are at record highs) aren’t particularly helpful here as BA.2 and BA.2.12.1 rose mostly in the northeast. But the figures for New York and Massachusetts (the main BA.2.12.1 states) may be more illuminating.
Over the past two weeks, the number of cases has increased 62% in New York and 51% in Massachusetts. Hospitalizations have also increased. Importantly, ICU admissions have remained remarkably stable — and low. In New York, in fact, the number of intensive care units as a share of overall hospitalizations has never been lower (at 11%). The same is true for Massachusetts (at 8%). Similarly, only 111 (or 29%) of the state’s nearly 400 hospitalized patients were classified as “predominantly hospitalized with illness related to COVID-19”; at the top of Omicron, that number was over 50%. Another telling statistic: 62% of Massachusetts patients currently hospitalized with COVID report having been fully vaccinated when they tested positive; before Omicron, this number was always closer to a third.
So for now, it looks like more patients in flagship states are testing positive for COVID when admitted to hospital, as more people are tested positive for COVID in surrounding communities – but BA.2 and BA.2.12.1 do not cause an increase in serious illnesses, probably thanks to vaccination.
It remains to be seen whether this pattern holds as BA.2.12.1 increases in prevalence. But according to the CDC, the new subvariant already accounts for more than 50% of infections in the New York area — and rates of case growth and test positivity may nonetheless begin to level off. In Massachusetts, sewage prevalence and the cases both appear to have plateaued; meanwhile, cases in Washington, DC, may begin to decline.
Coming out of a BA.2/BA.2.12.1 bump relatively unscathed could be a good sign for the future.
According to Bedfordthere are two plausible scenarios for the next year: (1) another “Omicron-like emergence event” in which a “highly divergent new virus” escapes existing immunity and upends society again, or (2 ) “development within BA”. 2″ to “further increase intrinsic transmission”, resulting in “lower attack rates”, largely “driven by drift + decay [immunity] + seasonality.
Bedford sees the second, stable and similar scenario as “more likely” – and says the more sublines like BA.2.12.1, the more likely it will become.
“The more time passes, the more certain we can be that another ‘Omicron-like’ emergence will not occur,” he said. has explained.
If Bedford is right, that suggests that future surges would be less like our huge Omicron winter surge than anything we’re experiencing now. And it would also increase the “likelihood that we end up moving to [a] vax with [an] Omicron spine”, according former Food and Drug Administration Commissioner Scott Gottlieb, which means greater stability, predictability, and infection protection in the future.
The most likely scenario
Maybe somewhere in the middle. BA.2.12.1 represents only 20% of current infections in the Massachusetts region; maybe it’s taking off and undoing recent progress there. Or perhaps high vaccination and booster rates in the Northeast mitigate the variant’s ultimate impact there — while lower rates leave less COVID-cautious states more vulnerable this spring. Or maybe seasonality and global warming are helping protect the South and West like they did last spring and summer.
On Twitter, a respected COVID modeler who goes by the hilt @JPWeiland job a prediction from earlier this week. Based on BA.2.12.1’s recent growth rates, the modeler said the variant had “a bigger chance of crossing the change of seasons to create a real wave than BA.2 could muster,” but said went on to say that because there was not much anticipated immune evasion with B.2.12.1, the wave should be inherently size limited. “We won’t see nearly 1 million cases/day in January, but we could see 200,000. Hard to say for sure.
Indeed, it is.