Unlike the influenza vaccine, which requires annual updates due to circulating virus strains, there is a notable absence of specific long-lived plasma cells for COVID-19.

The researchers identified that the structure of the coronavirus spike proteins likely contributes to inadequate plasma cell development, as B-cell receptors struggle to bind effectively to these proteins.

A recent study led by Dr. F Eun-Hyung Lee at Emory University, published in Nature Medicine, examined the immune response of 19 adults aged 20 to 65 who had received multiple doses of mRNA Covid-19 vaccines.

The research found that these mRNA vaccines do not lead to the formation of long-lived plasma cells in the bone marrow, which are crucial for sustained antibody production.

Bone marrow analysis revealed a significant lack of these long-lived plasma cells, limiting the body's long-term protection against Covid-19.

As a result, vaccination and previous infections do not provide long-term immunity against COVID-19, leading to increased susceptibility to reinfection over time.

This frequent reinfection, even among vaccinated individuals, is largely attributed to the virus's ability to mutate rapidly, evading existing immunity.

In contrast, antibody levels from mRNA vaccines tend to decline within a few months, while vaccines for other diseases, such as tetanus, can offer protection for up to a decade.

Participants in the study exhibited stable and long-lasting immune responses to vaccines for other diseases, highlighting the shortcomings of current Covid-19 vaccine technology.

The authors of the study emphasize the urgent need to improve the durability of protection offered by mRNA vaccines, as achieving long-lived plasma cells remains a critical goal of vaccine development.

These findings suggest a pressing need for further research into enhanced vaccine formulations or delivery methods to improve the duration of immunity against Covid-19.

Immunologist Martin Bachmann has proposed that virus-like particles may serve as a more effective platform for future COVID-19 vaccines compared to the current mRNA technology.