Current variations are unlikely to be protected by early Omicron infection
Key Takeaways:
- People who were infected with the first strain of the coronavirus Omicron, which was found in South Africa in November, may be vulnerable to later strains of Omicron.
- Garcia-Sastre, who was not involved in the study, predicts that by the time a variation-specific vaccine is available, another variant will have substituted it.
According to new research, people infected with the first strain of the coronavirus Omicron, discovered in South Africa in November, may be susceptible to reinfection with later strains of Omicron.
According to Chinese researchers who authored their findings in Nature on Friday, immunized patients with Omicron BA.1 breakthrough infectious diseases developed antibodies that could neutralize the virus and also the original SARS-CoV-2 virus. Still, the circulatory Omicron sublineages now have mutations that allow them to evade those antibodies.
Omicron BA.2.12.1, which is currently responsible for the bulk of infections in the US, as well as Omicron BA.5 through BA.4, which now account for more than 21% of new cases, have changes not found in Omicron BA.1 and BA.2.
The newer sublineages "substantially evade the neutralizing antibodies produced by SARS-CoV-2 infection and vaccination," the researchers discovered in test tubes.
Experiments also showed that monoclonal antibody drugs such as Eli Lilly's bebtelovimab and AstraZeneca's Evusheld's cilgavimab could neutralize BA.2.12.1 and BA.4/BA.5.
The researchers cautioned that vaccination boosters based on the BA.1 virus, such as those developed by Pfizer/BioNTech and Moderna, "may not deliver broad-spectrum protection towards new Omicron variants."
The unpublished study suggests that unvaccinated patients infected with Omicron are unlikely to establish immunological responses that protect them against other coronavirus types.
"While having an Omicron-specific vaccine may have some benefits," Dr. Onyema Ogbuagu, an infectious diseases analyst at Yale School of Medicine in New Haven, Connecticut, who was not interested in the current study, said, "I believe it will be of marginal value compared to staying current with existing vaccines and boosters."
"Vaccinations are still predicted to protect against serious disease despite immune evasion," Ogbuagu said. "Get a booster if you need one. We've learned in the clinic that remaining up to date on vaccines is crucial "to maintain high levels of COVID-19 antibodies in the blood.
Adolfo Garcia-Sastre, microbiology as well as infectious diseases researcher at Mount Sinai's Icahn School of Medicine, suggested that immunization that targets multiple stress of the virus or intranasal vaccines that increase protection from infection as well as transmission by generating immunity in the nasal passages, where the virus first enters, could provide better protection.
Garcia-Sastre, who was not involved in the research, believes that by the time one variant-specific vaccination is available, a new variant may have supplanted it.