Researchers at Oregon Health and Science University (OHSU) in the United States have found that people who have been vaccinated and infected with SARS-CoV-2, regardless of order, acquire immunity up to ten times greater than the immune protection of those who just received the vaccine. vaccine.
The research took place before the emergence of the Ômicron variant. The results were published in the journal Science Immunology.
The vaccine, however, remains the most important factor — especially since the natural protection offered by the infection is short-lived. “We will be more prepared if we are vaccinated. In this case, if the virus comes, you have a milder contamination and you still have greater immunity,” said Fikadu Tafesse, co-author of the research, and professor of molecular microbiology and immunology at the OHSU School of Medicine.
Marcel Curlin, a physician and also a co-author of the study, pointed out that the immunity acquired from the virus infection alone varies greatly from person to person. “The immunity conferred by natural infection alone is very variable. Some people produce a strong response, others don’t. But the vaccination combined with immunity from infection almost always offers strong responses,” he said in a statement.
This is not to say, of course, that people who have already been vaccinated and have not caught Covid-19 should forgo protection. Even though the Ômicron variant is considered lighter and the vaccines are taking effect, Covid is still a disease with intense symptoms and risk of death. In addition, there are the risks of long-term effects (the so-called long Covid) and the dangers of spreading the virus to children, overloading the health system – as explained in this report.
This is not the first research to point to such results. In December, researchers from the same university had already revealed, in another study, that the combination of the infection with the vaccine helped to have more protection.
In the new research, the scientists measured the neutralizing antibody responses of 104 subjects and divided them into three groups. In the first, 42 people who were vaccinated and had no infection; 31 who were vaccinated after an infection and 31 who had infections after vaccination.
The team took into account factors such as age, sex and time of vaccination and infection.
The researchers took blood samples from each participant and exposed them to three variants of the coronavirus at OHSU’s Marquam Hill Biosafety Level 3 laboratory.
The results showed that two groups with “hybrid immunity” — infected and vaccinated — can generate higher levels of antibodies compared to the group of vaccinates without infection, about 10 times more compared to those provided by vaccination.
Could Covid-19 become endemic?
Bill Messer, professor of molecular microbiology and immunology and medicine (infectious diseases) at the OHSU School of Medicine, and co-author of the study, believes that, at this point, many vaccinated people end up with infections — and thus a form of hybrid immunity.
For Curlin, “the results indicate that at some point SARS-CoV-2 could become a mild endemic infection, such as seasonal respiratory tract disease, rather than a pandemic” — which is the case with influenza.
The research did not test patients with Covid-19 reinfections.
Reference: CNN Brasil