CNN
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Two teams of U.S. scientists are testing vaccinations to see how well they protect against current variants of the virus that causes coronavirus infections, including the highly mutated BA.2.86. A laboratory experiment has been completed to test for antibodies in Americans who have been infected with the virus.
Their results match almost exactly, and this news is very good, at least for BA.2.86 (also known as Pirola). Our immune systems are able to recognize and fight off this variant as well or even better than the currently circulating derivatives of his XBB variant.
Additionally, those who had the strongest responses to BA.2.86 were those who had been infected with the XBB subvariant within six months. This suggests that the latest Covid-19 vaccines this fall, designed to fight off XBB.1.5, will provide additional protection against various circulating Covid-19 strains, including BA.2.86. I am.
“Two independent laboratories have essentially shown that BA.2.86 is not an additional immune escape compared to current variants,” said Beth Israel Deaconess Medical Center Virology and Vaccines. said Dr. Dan Baruch, director of the research centers and leader of one of the research institutes. he institute told CNN.
Their results are consistent with previous experiments by laboratories in China and Sweden. Taken together, the data suggests that BA.2.86 is not as troublesome as experts feared. In short, this seems like a “scary thing”.
However, another variant, FL.1.5.1, is causing problems. Estimated 15% The number of new coronavirus infections in the United States may tell a different story. The progeny of this rapidly growing her XBB recombinant mutant have a series of mutations that raise the eyebrows of mutation trackers. Laboratory tests showed the highest immune evasion.
“If there wasn’t so much hype about BA.2.86, that would actually be the focus of this paper,” Barouch said.
Barouch and his team used a pseudovirus. They created a spike of the BA.2.86 virus and attached it to the body of another virus. They then collected plasma, the clear part of blood, from 66 Americans who had only received the monovalent vaccine, those who had received the bivalent vaccine, or had recently recovered from an XBB infection, and found that their antibodies We tested how well it neutralized 10 omicron subvariants, including: BA.2.86.
They found that across different types of immunity, people can neutralize BA.2.86 as well as, and in some cases more effectively than, other circulating variants. did. Those with the highest neutralizing antibodies were those who had recently recovered from an XBB infection.
In the other lab, Dr. David Ho, a professor of microbiology and immunology at Columbia University, and his team used plasma from 61 adults. Of these, 17 had received three doses of monovalent vaccine and two doses of bivalent vaccine, and 25 had recovered from BA. .2 people with breakthrough infections and his 19 who have recovered from his XBB breakthrough infections.
His results were substantially similar to Barosh’s. Across different immune profiles, antibodies in his blood were able to recognize BA.2.86 as well as other circulating variants. The person with the highest immunity to BA.2.86 was the one who had recovered from her recent XBB infection.
This was surprising because there are so many mutations in BA.2.86. Scientists had predicted, based on what was known about these particular mutations, that it could be highly immune evasive.
Barosh said he couldn’t believe the first results, so the lab repeated the experiment all weekend. The result was the same.
“It wasn’t exactly what I expected,” he said. “Now that they’ve been repeated, we’re confident about them now.”
Baroush said he had been asked to brief the White House and the U.S. Centers for Disease Control and Prevention on the findings. “I think these results are quite significant,” he said.
Scientists around the world are rushing through laboratory experiments to understand the BA.2.86 variant.
Two teams from the United States and four groups from labs in China and Sweden reported their results. Early results paint BA.2.86 as a papier-mâché tiger rather than the looming beast it first appeared, but that impression may change as more results are obtained.
BA.2.86 caught the world’s attention because it is fundamentally different from other coronavirus variants identified to date.
This new strain has more than 30 changes in the spike protein compared to its next closest ancestor, BA.2, and the recently circulating XBB.1.5 strain. This is an evolutionary leap on par with when his original Omicron variant, BA.1, came out about two years ago, and we all remember how that happened.
During the Omicron waves, infectious diseases and hospitalization strike The high point of the pandemic in the United States.weekly death toll second highest It’s a lesson in how even milder versions of the virus can pose a serious threat if they cause a tsunami of infection across a population. I needed to update my vaccine.
Omicron quickly overtook other Covid-19 variants and began creating its own derivative viruses, the ones we are still dealing with today. This was a lesson in how agile the virus is and how fragile our defenses are in the face of such major changes.
The White House is sufficiently concerned about another Omicron-level event that it secretly surveyed about a dozen experts earlier this year about the likelihood of the world seeing a similar event within the next two years. .Most experts suggest that possibility Between 10% and 20%.
So when BA.2.86 appeared in late July with an eerie echo of Omicron, subspecies hunters were horrified and researchers sprang into action to learn more about the new lineage. The virus has spread to at least 11 countries, including the United States.
The country that has reported the most sequences so far is Denmark, and experts say they are closely monitoring the situation there for clues to the spread.
However, only about 30 sequences from the same number of infected patients have appeared in the global repository over the past month. Experts think it’s clear if BA.2.86 is becoming more powerful, even if there is far less genetic surveillance than there used to be.
“My friends, this is not the second coming of Omicron. If it were, it’s safe to say we would know it by now,” said epidemiologist Bill Hanage, Ph.D., co-director of the Center for Infectious Disease Dynamics at Harvard University. said. social media posts.
Scientists are currently conducting experiments in the lab to better understand how well our immune systems and vaccines recognize and protect against viruses in the BA.2.86 family.
In an initial series of experiments using vaccinated mice and the blood of recently infected people, Chinese researchers found that BA.2.86 was an earlier version of the virus that caused COVID-19. confirmed that it actually looks different to the human immune system compared to other viruses. And it can escape some of our immunity.
Yunlong Cao, a researcher at the Peking University Biomedical Innovation Center, said the ability of immunity from vaccination or recent infections to neutralize the BA.2.86 virus is two times lower than for viruses in the XBB.1.5 family. He said that
A 2x decrease isn’t great, but it’s not huge either. By comparison, a one-eighth reduction in the ability of vaccine-generated immunity to neutralize new influenza viruses is the benchmark scientists use to update influenza vaccinations.
At the same time, the BA.2.86 variant is about 60% less transmissible than the XBB.1.5 virus, which experts believe could explain why it was found. A large number of countries are participating, but at a low level.
“I think it will spread through the population slowly. It will not be able to compete with other rapidly spreading variants,” Cao said in an email to CNN, adding that it is currently dominating transmission in the US. He mentioned variants such as EG.5 and FL.1.5.1.
In a second set of experiments, researchers at Sweden’s Karolinska Institute tested antibodies and BA in the blood of human donors taken at two time points: in late 2022 and in late August, before the emergence of the XBB variant. Compare 2.86.
The antibodies inside are Older samples were unable to effectively shut down BA.2.86, but blood samples taken from donors just a week earlier were more effective.
“Overall, this appears to be a less extreme situation than the first Omicron appearance,” lead researcher Benjamin Murrell wrote in the paper. Post on social media.
“It is not yet clear whether BA.2.86 (or its descendants) will compete with the variants currently in circulation, and we do not yet believe we have data on its severity, but our antibodies may .2.86 doesn’t seem to be completely ineffective against it.” That’s it,” he wrote.
All of these studies have limitations. Researchers were testing a pseudovirus, which is essentially a model of what the BA.2.86 virus looks like, rather than the virus itself. The Swedish study used only a small number of samples from blood donors. And because these studies used blood donors from China and Sweden, they may reflect immunity in people in the U.S. who may have been infected with different types of variants and vaccinated with different vaccines. It’s possible that you haven’t.
Still, experts said they were encouraged by these early results and hoped to see more results.
“This news was better than I expected,” said Dr. Ashish Jha, former White House coronavirus response coordinator. Post to social media. “And we are even more encouraged that new vaccines coming out will have real efficacy against the current dominant variants (EG.5) and BA.2.86.”
The UK Health and Safety Executive’s Variant Technical Group met last week to consider whether BA.2.86 should be reclassified from a “variant under surveillance” to a “variant of concern” in the country.
in Update information has been posted The group concluded Friday that BA.2.86 does not meet the definition of a variant of concern. This is because there is no evidence that this profile exhibits deleterious changes in its biological properties or at least in growth rates that would suggest that it moves as follows. It is as fast as or faster than the currently circulating variants.
The group said two samples of the virus were being cultured in the UK and data from those experiments was likely to be available for at least a week or two. Meanwhile, the group is keeping an eye on achievements from international partners.
They, like the rest of the world, are waiting for BA.2.86 to reach out.