BA.2, a More Contagious Cousin of the Dominant BA.1 Subvariant of the Omicron Variant of SARS-CoV-2

There are signs a new wave of COVID is building. BA.2, a more contagious cousin of the dominant BA.1 subvariant of the Omicron variant of SARS-CoV-2, has been spreading fast in Europe and China in recent weeks.

Now it’s starting to show up more frequently in samples of waste water in major American cities, including Atlanta, New York City, Chicago, and Seattle, according to the US Centers for Disease Control and Prevention.

The warning signs come as most of the US and Europe drop the last few major restrictions on business, travel, schooling, and public gatherings. Stores and restaurants are fully open. Concerts and other events are back on. Mask mandates are disappearing.

Mitigation efforts ending at the same time cases are increasing might seem like a recipe for disaster. But don’t panic—at least not yet. We’re probably reasonably ready for BA.2, even without a bunch of public-health mandates. Whether we’ll be ready for whatever comes after BA.2… well, that remains to be seen.

“I’m not necessarily at the level of being worried right now, but this is something to watch because BA.2 is even more transmissible than BA.1,” Cindy Prins, a University of Florida epidemiologist, told The Daily Beast.

Experts disagree on just how much more transmissible BA.2 is, compared to BA.1. Some say 30 percent more. Others, 50 percent more. In any event, it’s all but inevitable that the subvariant will outcompete other forms of the novel coronavirus and become the dominant variant in the US

More than two years into the pandemic, the march of new variants and subvariants, once they first appear, is pretty predictable. “The trend in Europe has been three-to-six weeks ahead of us, five waves of COVID-19 and counting,” Eric Bortz, a University of Alaska-Anchorage virologist and public-health expert, told The Daily Beast.

Mark your calendar. Around half of European countries registered increases in new COVID cases in the past week—almost all of them BA.2. At the same time, Chinese authorities have locked down the city of Shenzhen, near Hong Kong, after detecting a surge in infections that experts attribute to the new subvariant.

Now project a month or so into the future. BA.2, with its elevated transmission rate, could be dominant in the US in early summer, Edwin Michael, an epidemiologist at the Center for Global Health Infectious Disease Research at the University of South Florida, told The Daily Beast. That chimes with Bortz’s prediction of a six-week delay between European and US COVID surges.

Whether BA.2’s coming takeover in America will drive major increases in the metrics that really matter—serious illnesses, hospitalizations, deaths and long COVID—is an open question.

Surveillance of sewer systems—in essence, scooping up water samples and testing them for the virus—only hints at a possible increase in infections. And an increase in infections might not cause a commensurate increase in hospitalizations, deaths and long-term impacts on infected people.

“Remember, it’s not 2020,” Jeffrey Klausner, a professor of medicine and public health at UCLA who previously worked at the CDC, told The Daily Beast. “We have surveillance, widespread testing, vaccination, high levels of immunity against severe disease and highly effective antiviral therapy.”

Bortz told The Daily Beast he expects the BA.2 wave in the US to be smaller and less destructive than the one that preceded it. For that reason, he referred to it as a “wavelet.”

“The peak of the Omicron BA.2 wavelet when it arrives may well be significantly smaller than previous waves in terms of severe disease—hospitalizations and deaths—because a large fraction of the US population has some degree of immunity, from vaccination, infection, including with Omicron BA1, or both,” Bortz said.

That outcome would be consistent with the overall trend. The wave of BA.1 infections that began around Thanksgiving last year put a lot of people in the hospital, but it didn’t kill the same proportion as died in the previous wave, driven by the Delta variant in late 2020 and early 2021.

Two women walk by closed shops in Huaqiangbei area, the world’s biggest electronics market, in Shenzhen in south China’s Guangdong province.

Feature China/Future Publishing via Getty

It’s not hard to explain this trend. Every infection produces natural antibodies that protect a survivor for months. Each successive COVID surge crashes into the wall of immunity left behind by the previous surge. Plus, we’ve got new prescription COVID pills and an array of therapies that can reduce the risk of death in all but the most severe cases.

Most importantly, we have highly effective, safe and free vaccines. And they still work just fine, even as SARS-CoV-2 keeps mutating. “As with the BA.1 version, being fully vaccinated and boosted provides good protection against BA.2,” Prins said.

So be wary, but don’t freak out. Yes, COVID is coming for us yet again. But we’re better prepared than ever before, even with the widespread lifting of public-health measures such as mask-mandates and restrictions on businesses and schools.

The same can’t be said of our readiness for any new variant that might come after BA.2. “Right now COVID-19 remains very unpredictable and deadly,” Irwin Redlener, the founding director of Columbia University’s National Center for Disaster Preparedness, told The Daily Beast. “We have no idea of ​​where this is going.”

Most worryingly, natural and vaccine-induced immunity wane over time. If some highly transmissible new variant strikes in a year or so, after our antibodies from the last 15 months of vaccinations and the recent Omicron waves have faded, we might be mostly defenseless.

People wearing face masks to protect against the spread of coronavirus walking in El Postiguet beach of Alicante as COVID-19 cases are increasing in Spain.

Marcos del Mazo/LightRocket via Getty

At that point, preventing catastrophic numbers of hospitalizations and deaths would require major new restrictions on businesses, travel, schools and gatherings and an aggressive effort to administer additional doses of the best vaccines.

In that scenario, early 2023 could look a lot like early 2020. To prevent this outcome, get vaccinated, get boosted, listen to the experts and be flexible and patient if and when we need to start masking up in some situations and limiting some crowds again. “This virus has taught us to remain vigilant and keep an eye on all mutations,” Ali Mokdad, a professor of health metrics sciences at the University of Washington Institute for Health, told The Daily Beast.

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