Early research suggests that people who are vaccinated and then infected with omicron may be primed to beat a wide range of coronavirus variants.
A couple of studies have shown that infection produces better immune responses than the booster vaccine in vaccinated patients. Teams from Covid-19 vaccine maker BioNTech SE and the University of Washington have published the results on their bioRxiv prepress server in recent weeks.
The results provide a reassuring sign that the millions of vaccinated people who have omicron may not develop serious illness from another variant soon – although the research needs to be confirmed, especially with real-world evidence.
“We should think of a superinfection as essentially equivalent to another dose of the vaccine,” said John Wehrey, a professor and director of the Institute of Immunology at the University of Pennsylvania who was not involved in the research but reviewed the BioNTech study. That could mean that if someone had Covid recently, they could wait before getting another booster dose, according to Wehrey.
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Alexandra Walls, the lead scientist at the University of Washington who authored one of the studies, cautioned that people should not look for infections in response to the findings.
The data comes as omicron continues to fuel outbreaks around the world, most notably in China, where Shanghai residents have been locked in for nearly six weeks. Waves of new variants are coming more quickly in part because Omicron is so highly transmissible, giving it ample opportunity to spread and transform as states deregulate, said Sam Fadley, an analyst at Bloomberg Intelligence. Meanwhile, regulators are weighing whether Covid vaccines should be updated to target Omicron.
The BioNTech team argued that the data suggested that delivering an omicron-adapted booster dose might be more beneficial than many of the original vaccines.
The Washington research, conducted with Vir Biotechnology Inc. , blood samples from people who became infected, then took two or three doses of the vaccine, as well as those who picked up the delta and omicron variants after two or three doses. ; Still others have been vaccinated and boosted but never had Covid. The latter group had only been infected with omicron and had never been vaccinated.
Part of the study focused on antibodies, which are protective proteins designed to recognize and neutralize invaders. showed that vaccinated people who had been infected with omicron had antibodies that outperformed the others. They were even able to recognize and attack the very different delta variant.
“This suggests that we’ve reached a point where we might want to consider having a different vaccine to boost people,” said David Wessler, an assistant professor at the University of Washington, who led the research. The scientists were also able to identify antibodies in the nasal mucus of these patients, which can help them neutralize the virus once it enters the body.
Read also: Data shows Long Covid risk worse after Delta than Omicron
The Washington and BioNTech studies also looked at another piece of the immune system: B cells, a type of white blood cell that can go off to produce a batch of new antibodies if it recognizes a pathogen. The BioNTech team found that people who had a penetrating omicron infection had a broader response from these beneficial cells than those who got the booster dose but didn’t have any.
Crucially, the Washington team also found that a broad response was missing in unvaccinated people who had omicron as their first exposure to the virus. “That would be a problem if a new, significantly different variant emerged,” Weissler said.
There is no guarantee that future mutations will be as mild as an omicron, and the future of an epidemic is difficult to predict because it depends not only on immunity in a population, but also on how mutated the virus is.
Other researchers who reviewed the studies said the findings match the growing body of evidence that immunity is enhanced from exposure to different viral variants through vaccination and infection. The scientists also showed broad immune responses in people who developed delta after taking their doses.
“This is probably an indication that an updated booster might be a good idea,” said Theodora Hatziwano, a Rockefeller University virologist who helped lead a research team into superinfection in a group of vaccinated people in New York City.