PARIS, FRANCE – People can fight reinfection for at least six months after recovering from COVID-19 thanks to cells that can “remember” the virus, according to research published Monday.
Researchers in the United States and Switzerland studied dozens of people who had recovered from COVID-19 and found that while their antibodies may disappear over time, they maintained specific B cell levels of memory.
These cells can recall the pathogen and, if faced with reinfection, can drive the immune system to restart the production of antibodies against the virus.
“Responses to memory are responsible for protection against reinfection and are essential for effective vaccination,” the study published in the journal Nature concluded.
“The observation that memory B cell responses do not decline after 6.2 months, but continue to evolve, is strongly suggestive that people infected with SARS-CoV-2 may respond quickly and effectively. to the virus after re-exposure. “
The authors evaluated 87 people with a confirmed diagnosis of COVID-19 just over a month and six months after infection.
Although they found that the activity of neutralizing antibodies to the virus decreased over time, the number of memory B cells remained unchanged.
The researchers said their study indicated that the response of memory B cells to coronavirus evolves during the six months following infection in the presence of viral residual proteins in the body, allowing cells to produce more potent antibodies.
The time to combat the reinfection of the new coronavirus and the immune process involved are key to predicting the dynamics of the pandemic.
Previous research has caused concern by showing that neutralizing antibodies can decrease rapidly after SARS-CoV-2 infection.
But more recent studies have highlighted the role of other parts of the immune system in long-term immunity.
An article published in the journal Science this month suggested that almost all major parts of the immune system that can learn to recognize and repel a new pathogen could continue to respond to the virus for at least eight months.
This included peak-specific memory B cells, which the researchers found actually increased in the blood six months after infection.
The paper was based on analysis of blood samples from 188 COVID-19 patients.