Published Tuesday in the journal Science Immunology, Sun and colleagues’ research fully documents for the first time the underperforming immune response in the airways of people with COVID-19 vaccinations compared to those with natural infection.
The leading vaccines in public use are called “mRNA vaccines” because they take inspiration from messenger ribonucleic acid, the delivery system that facilitates biological replication. But the mRNA in the vaccines is not derived from a live virus. Instead, the molecule is synthesized in a lab to resemble an invader, enough so that the body can recognize the real thing in the future. However, with these vaccines, “the message” now appears to be largely confined to the blood.
Bloodstreams get strongly ramped up by the vaccine, while the mucosal linings experience moderate or little neutralizing antibody response, the study found.
“The omicron variant almost completely escaped neutralization by mucosal antibodies in individuals who received mRNA vaccines and in previously infected individuals,” Sun said. “Our data showed that mRNA vaccination also did not induce sufficient tissue-residing cellular immunity in the airways, another arm of our immune system to prevent the entry of the virus into our bodies.”
Only the bodies of unvaccinated patients who were seriously ill put up a vigorous fight against the virus in both their airways and their bloodstreams, the researchers found – a less-than-ideal way of achieving a united front.