Many recent studies agree Moderna and Pfizer COVID-19 vaccines lose some effectiveness over time. Although the vaccines do continue to provide robust protection against severe symptoms that may even prove fatal. A Mayo Clinic study, for example found Moderna effectiveness against Delta dropped to 76%. While Pfizer was far less successful at 42%. However, the immunity continues for longer.
The Three Components of Our Immunity System
But we still have a better prospect of staying out of hospital, according to the Mayo study. WebMD explains this is because there are three components to our immune system, each with their own distinct role:
1… The vaccination’s neutralizing antibodies find and bind to the virus, preventing it from invading host cells.
2… However, if a virus still does enter a host cell, T cells spot it and report the invasion to B cells.
3… The B cells respond by manufacturing antibodies to fight the virus and stop it from replicating.
4… While T cells follow up, and destroy any remaining virus fragments on the surface of the host cell.
How Immunity Continues After Antibodies Lose Some Ability
Alessandro Sette is a doctor of biological science. And professor at the Center for Autoimmunity and Inflammation, and Center for Infectious Disease and Vaccine Research at La Jolla Institute for Immunology in California. He says the T cell response remains effective, even after antibodies lose some ability to neutralize a variant.
Therefore, the T cells can still attack a virus after it enters a host cell. ‘This is exactly what we are seeing,’ he explains. ‘Obviously, this is good news.’ But that is not the only cause for his optimism.
The memory B cells charged with making antibodies also have a “fascinating capacity” to adapt and change over time. And this means immunity continues for longer, and they can continue to help neutralizing infections.
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Preview Image: Immune System Components
