However, COVID-19 vaccination is still expected to provide substantial protection against severe disease, and vaccine manufacturers are working on updated shots that can elicit a stronger immune response against the variants.
“We observed a 3-fold reduction in neutralizing antibody titers induced by vaccination against BA4 and BA5 and against BA1 and BA2, which are already significantly lower than those of the original COVID-19 variants,” said paper author Dr. . Dan Baruch and director of the Center for Virology and Vaccine Research at Beth Israel Deaconess Medical Center in Boston, wrote in an email to CNN.
“Our data suggest that these new omicron subvariants will likely be capable of attenuating infection in populations with high levels of vaccine immunity as well as natural BA1 and BA2 immunity,” Baruch wrote. “However, it is likely that vaccine immunity will still provide adequate protection against severe disease with BA4 and BA5.”
The newly published findings echo separate research by scientists at Columbia University.
They recently found that the BA.4 and BA.5 viruses are more likely to escape antibodies from the blood of fully vaccinated and grown adults than other omicron subvariants, leading to vaccine-successful COVID-19 infections. risk increases.
BA.4 and BA.5 are by far the fastest-spreading variants, and are expected to dominate COVID-19 transmission in the United States, the United Kingdom and the rest of Europe within the next few weeks, according to the European Center for . Disease prevention and control.
‘Covid-19 still has the potential to change’
In a New England Journal of Medicine paper, in 27 research participants who were vaccinated and boosted with the Pfizer/BioNTech coronavirus vaccine, researchers found that two weeks after a booster dose, neutralizing antibodies against the Omicron subvariant were increased. The level was too low. The original response against the coronavirus.
Neutralizing antibody levels were less than a factor of 6.4 against BA.1; by a multiple of 7 against BA.2; The researchers describe a multiple of 14.1 against BA.2.12.1 and a multiple of 21 against BA.4 or BA.5.
Among the 27 participants who were previously infected with the BA.1 or BA.2 subvariants for an average of 29 days, the researchers found similar results.
In people with previous infections – most of whom had also been vaccinated – the researchers described neutralizing antibody levels that were less than a factor of 6.4 against BA.1; by a factor of 5.8 over BA.2; By a factor of 9.6 against BA.2.12.1 and by a factor of 18.7 against BA.4 or BA.5.
More research is needed to determine what neutralizing antibody levels really mean for vaccine effectiveness and whether similar findings would emerge among a larger group of participants.
“Our data suggest that COVID-19 still has the potential to mutate further, resulting in increased transmittance and increased antibody escape,” Barouch wrote in the email. “As pandemic restrictions are lifted, it is important that we remain vigilant and continue to study new forms and subtypes as they emerge.”
What this means in the real world, says Dr., an experimental pathologist at Houston Methodist Hospital. Wesley Long told CNN that people should be aware that they can get sick again, even if they have had COVID-19 before.
“I think I’m a little worried about people who have a false sense of security on the recent BA.4 and BA.5 growth, because we’ve seen some cases of re-infection and I’ve seen some Cases of re-infection with people with BA.2 variant in the last few months,” he said.
Some vaccine manufacturers are developing variant-specific vaccines to improve antibody responses against coronavirus variants and subvariants of concern.
“Unless we have vaccines or broad mandates that are going to stop cases from rising again, reinfection is going to be pretty inevitable. But the good news is that we’re much more likely than we are without vaccines.” In a better place,” he said. Pavitra Roychowdhury, an acting instructor in the University of Washington’s Department of Laboratory Medicine and Pathology, who was not involved in the New England Journal of Medicine paper.
“There’s so much of this virus out there that it seems inevitable,” she said of the Covid-19 infection. “Hopefully, with the protection we have in place, most mild infections are going to happen.”
Efforts underway to update Kovid-19 vaccines
This bivalent booster vaccine candidate contains components of both Moderna’s original COVID-19 vaccine and a vaccine that targets the Omicron variant. The company said it is working to complete regulatory submissions in the coming weeks requesting to update the composition of its booster vaccine to mRNA-1273.214.
“In the face of continued development of SARS-CoV-2, we are very encouraged that mRNA-1273.214, our prime booster candidate for degradation, showed high neutralizing titers against the BA.4 and BA.5 subvariants, representing a contingency.” are a threat to global public health,” Moderna’s Chief Executive Officer Stefan Bansel said in Wednesday’s announcement. SARS-CoV-2 is the coronavirus that causes Covid-19.
Bansal said, “We will immediately submit these data to regulators and are preparing to supply our next-generation bivalent boosters starting in August, in the early fall of SARS-CoV-2 infection due to the Omicron subvariant.” before the potential increase.”
Data that Moderna released on Wednesday, which has not been published in a peer-reviewed journal, showed that a 50 microgram dose of the mRNA-1273.214 vaccine was released one month after people who had been vaccinated. and was vaccinated. potent” neutralizing antibody responses against BA.4 and BA.5, increasing levels by 5.4-fold in all participants regardless of whether they had prior COVID-19 infection and 6.3-fold in a subset of those who had prior With no history of infection, Modern said these levels of neutralizing antibodies were about 3 times lower than the previously reported neutralizing levels against BA.1.
These findings add to data that Moderna released earlier this month, showing that a 50-microgram dose of the bivalent booster produced a stronger antibody response against Omicron than the original Moderna vaccine.
Ward said in part, “It has been previously reported that bivalent vaccines are well tolerated with temporary ‘reactionary’ effects similar to those following unequal booster injections, so we can infer that This new compound vaccine should be well tolerated.” “As we move towards autumn with Omicron variants dominating the COVID infection landscape, it certainly makes sense to consider the use of this new bivalent vaccine, if available.”
CNN’s Brenda Goodman contributed to this report.