“What we will ultimately want is to have the host be ahead of the virus. Right now, she says, we’re in a race against the virus, and the key question is, who’s in the lead? And so that’s pushing back on things,” she said. The virus matters, she says, but as its would-be hosts, so do we.
“One of the caveats that we have to think about as we get new variants that might seem more dangerous is the fact that there’s two sides to the story,” Fuller says. Even though BA.2 seems more contagious and pathogenic than Omicron, it may not wind up causing a more devastating wave of Covid-19 infections. And BA.2 was almost completely resistant to some monoclonal antibody treatments.īut there was a bright spot: Antibodies in the blood of people who’d recently had Omicron also seemed to have some protection against BA.2, especially if they’d also been vaccinated.Īnd that raises an important point, Fuller says. It was also resistant to the antibodies of people who’d been infected with Covid-19 early in the pandemic, including Alpha and Delta. Similar to the original Omicron, BA.2 was capable of breaking through antibodies in the blood of people who’d been vaccinated against Covid-19. In tissues samples, the lungs of BA.2-infected hamsters had more damage than those infected by BA.1. When the researchers infected hamsters with BA.2 and BA.1, the animals infected with BA.2 got sicker and had worse lung function. Delta was also good at creating syncytia, which is thought to be one reason it was so destructive to the lungs. That’s concerning because these clumps then become factories for churning out more copies of the virus. This allows the virus to create larger clumps of cells, called syncytia, than BA.1.
It’s also more adept at causing cells to stick together. The new study found that BA.2 can copy itself in cells more quickly than BA.1, the original version of Omicron. Resistant to monoclonal antibody treatments But in Denmark, where BA.2 has become the leading cause of infections, hospitalizations and deaths are rising, according to WHO. Hospitalizations continue to decline in countries where BA.2 has gained a foothold, like South Africa and the UK. It has become dominant in at least 10 other countries: Bangladesh, Brunei, China, Denmark, Guam, India, Montenegro, Nepal, Pakistan and the Philippines, according to World Health Organization’s weekly epidemiological report.īut, there’s mixed evidence on the severity of BA.2 in the real world. The US Centers for Disease Control and Prevention estimates that about 4% of Americans with Covid-19 now have infections caused by BA.2, but many other parts of the world have more experience with this variant. It has been detected in 74 countries and 47 US states. Mixed real-world data on subvariant’s severityīA.2 is about 30% to 50% more contagious than Omicron. “It looks like we might be looking at a new Greek letter here,” agreed Deborah Fuller, a virologist at the University of Washington School of Medicine, who reviewed the study but was not part of the research. “Establishing a method to detect BA.2 specifically would be the first thing” many countries need to do, he says. Labs therefore have to take an extra step and sequence the virus to find this variant. That’s because it doesn’t show up on PCR tests as an S-gene target failure, the way Omicron does. “As you may know, BA.2 is called ‘stealth Omicron,’ ” Sato told CNN. Kei Sato, a researcher at the University of Tokyo who conducted the study, argues that these findings prove that BA.2 should not be considered a type of Omicron and that it needs to be more closely monitored. It also has dozens of gene changes that are different from the original Omicron strain, making it as distinct from the most recent pandemic virus as the Alpha, Beta, Gamma and Delta variants were from each other. Rhoads reviewed the study but was not involved in the research.īA.2 is highly mutated compared with the original Covid-causing virus that emerged in Wuhan, China.
Daniel Rhoads, section head of microbiology at the Cleveland Clinic in Ohio. “It might be, from a human’s perspective, a worse virus than BA.1 and might be able to transmit better and cause worse disease,” says Dr. Preprints allow research to be shared more quickly, but they are posted before that additional layer of review. Normally, before a study is published in medical journal, it is scrutinized by independent experts. The findings were posted Wednesday as a preprint study on the bioRxiv server, before peer review.