In the short time since the emergence of Omicron, the latest SARS-CoV-2 variant, many questions have arisen. Is it more transmissible, how bad are the symptoms, and most importantly, will the vaccines protect against it? Until more data are available, there are no firm answers, but many are optimistic that vaccines offer at least some protection. Medical News Today investigated the current hypotheses.
The rapid development of vaccines gave hope that the COVID-19 pandemic might soon be under control. In many countries, as the vaccines were rolled out, the virus abated. Hospitalizations and deaths from COVID-19 reduced in countries with widespread vaccine coverage.
Then came the Omicron variant of SARS-CoV-2. This new variant of concern, whose scientific name is B.1.1.529, was first identified in South Africa, though it may have originated in Europe, according to data from the Netherlands.
Omicron is now spreading in several countries. A study, which was conducted in South Africa and released last week but has yet to be peer reviewed, suggests that Omicron can evade immune defenses, leading to reinfection in people who have recovered from COVID-19.
These findings add to concerns that the COVID-19 vaccines authorized in most countries may not be effective against the Omicron variant.
Will the vaccines work?
Vaccine manufacturers are cautiously optimistic. Oxford University, which developed a vaccine with AstraZeneca, has stated: “Despite the appearance of new variants over the past year, vaccines have continued to provide very high levels of protection against severe disease, and there is no evidence so far that Omicron is any different. However, we have the necessary tools and processes in place for rapid development of an updated COVID-19 vaccine if it should be necessary.”
Pfizer also sought to allay fears in a statement: “Pfizer and BioNTech are remaining vigilant and constantly conducting surveillance efforts focused on monitoring for emerging variants that potentially escape protection from our vaccine. We are beginning to run neutralization tests on the new Omicron variant of concern and expect to have initial data in the coming weeks.”
“In the event that a variant emerges that escapes protection of our vaccine, Pfizer and BioNTech expect to be able to develop and produce a tailor-made vaccine against that variant in approximately 100 days, subject to regulatory approval,” the Pfizer spokesperson added.
Tim Spector, a professor of genetic immunology at King’s College London and scientific co-founder of ZOE, which boasts the world’s largest COVID-19 study, commented in an interview with MNT:
“The vaccines are highly likely to be effective against severity, and modestly against infection with Omicron.”
This view was echoed by Dr. Arturo Casadevall, chair of the molecular microbiology and immunology department at the Johns Hopkins Bloomberg School of Public Health, who told us: “I believe that current vaccines will provide some protection against Omicron. I am optimistic that the vaccinated will have some protection against Omicron and that this protection will continue to reduce symptoms and mortality in those affected.”
Spike protein changes
The chief worry is that the Omicron variant has more than 50 mutations, 30 of which are in the spike protein, the area that vaccines target.
Experts have expressed concern that the antibodies generated by vaccination will therefore not match the spike proteins of the Omicron variant, reducing the levels of immunity provided.
However, it appears that high levels of neutralizing antibodies, produced after three vaccine doses, provide protection from severe symptoms following infection with the Omicron variant.
It is not only the spike protein that stimulates the immune response, as Dr. Casadevall pointed out:
“Even though there are large changes in the structure of the spike protein between Omicron and the virus used to design the vaccine, much of it remains the same, and these common areas should elicit immune responses to Omicron.”
– Dr. Arturo Casadevall
Vaccines also stimulate other parts of the immune response. This results in the production of T cells, which play an important role in controlling SARS-CoV-2 infections and are less affected by spike mutations.
Get the jab
Both Prof. Spector and Dr. Casadevall stressed that vaccination is the best way to avoid getting seriously ill from COVID-19 — regardless of the variant.
“This will hit the unvaccinated more,” emphasized Prof. Spector.
Studies from Israel and the United Kingdom suggest that booster campaigns are decreasing the virus’s reproduction and associated hospitalizations.
Increasing vaccination should slow the pandemic, even in the face of the new variant.
Dr. Casadevall remains optimistic about the protection from current vaccines: “I believe that when it comes to this coronavirus, some immunity is better than no immunity. The vaccinated will have some protection against Omicron, and this protection will continue to reduce symptoms and mortality in those affected.”
Vaccination not only prevents serious illness and death. As Prof. Spector added: “Evidence from Delta [variant outbreaks] says the vaccine helps prevent long COVID. I think this will be the case with Omicron [as well].”
He continued: “Delta is still affecting 1 in 60 [people] in the U.K., and Omicron will spread very fast. People need to act sensibly.”
Dr. Casadevall reiterated this message: “Vaccines continue to be our best bet against Omicron, and people should be vaccinated and boosted.”
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