Covid-19 antibodies decline quickly: Study explains why

Recent research indicates that mRNA Covid-19 vaccines may not generate long-lasting immune protection.

Recent research suggests that protective antibodies from Covid-19 vaccines, specifically the mRNA type, tend to decline within a few months. This leaves individuals more susceptible to reinfection over time.

Unlike vaccines such as tetanus, which can provide protection for up to a decade by creating long-lasting immune cells, the Covid-19 vaccines appear less able to establish these durable defenses.

Scientists, led by Dr F Eun-Hyung Lee at Emory University, conducted a study, published in Nature Medicine, on 19 adults aged 20 to 65 who had received multiple doses of mRNA Covid-19 vaccines.

By analysing bone marrow samples, researchers discovered that while antibodies were present initially, the immune cells responsible for sustained antibody production over the long term, called long-lived plasma cells, were largely absent.

This absence limits the body's ability to maintain strong, enduring protection against Covid-19.

In contrast, the same participants showed more stable, long-lived immune responses to vaccines for other diseases, like tetanus and influenza, indicating that the Covid-19 vaccines might not encourage the maturation of immune cells into long-lived plasma cells.

Dr Lee explained to the US medical health body, the National Institutes of Health, that creating vaccines that stimulate these lasting cells is key to achieving enduring immunity.

"Our findings show that current mRNA Covid-19 vaccines fall short in generating long-lived plasma cells," she said, suggesting that further research on updated vaccines or delivery methods is essential to improve immunity duration.

This study opens up new directions for enhancing Covid-19 vaccines to provide stronger, longer-lasting protection.