When COVID-19 vaccines were introduced to the public, the mRNA vaccine from Pfizer/BioNTech and Moderna caught the public's attention because it was not the conventional vaccine type used as protection against viruses.
Clinical trials and studies have shown that it can give up to 90% protection against SARS-CoV-2 to prevent symptomatic infection, which surpasses the 50% threshold set by the Food and Drug Administration (FDA) to be considered for emergency use authorization.
As the world nears the second anniversary of COVID-19, breakthrough cases also emerged, but the protection the mRNA vaccine provided remained effective in preventing hospitalizations and deaths. So, what makes it so effective against the deadly virus?
How Does mRNA Vaccine Works?
Most vaccines use vector virus or the weakened/inactivated form to elicit an immune response from the body's immune system. But the mRNA vaccine works differently.
It uses mRNA created in a laboratory to elicit the immune response and produce antibodies to protect the host from getting infected with the real virus. But in the case of breakthrough cases, it lowers the risk of hospitalizations and deaths. Here's a step-by-step process of how mRNA works, according to the Centers for Disease Control and Prevention (CDC):
- When the COVID-19 mRNA vaccine enters the muscle cells given through the upper arm muscle, it instructs the machinery of the cell to produce a harmless spike protein, which is found on the surface of the SARS-CoV-2. Then, the body's cells will break the mRNA and eliminate it.
- The cells will then exhibit the spike proteins on their surfaces, and the immune system will recognize the protein as a foreign object, triggering the production of antibodies and activating immune cells to fight a perceived infection. This is how the immune system works against any viruses.
- Lastly, the body has now learned what the virus looks like and how to protect the body against future infection from SARS-CoV-2. Temporary discomfort after getting the vaccine is a natural part of immunization and indicates that the vaccine is working.
Why is mRNA Vaccine So Effective?
Medical Xpress reported that researchers from Washington University School of Medicine in St. Louis and St. Jude Children's Research Hospital explained what makes the mRNA vaccine effective.
They wrote in their study, titled "SARS-CoV-2 mRNA Vaccination Elicits a Robust and Persistent T Follicular Helper Cell Response in Humans" published in the journal Cell, that Pfizer/BioNTech mRNA vaccine strongly and persistently activates the T-follicular helper cells that could last for up to six months to help the immune system create immune memory and produce antibodies.
Once it wanes, the B cells will now help provide immunity against severe disease and mortality. The team further explained that the Pfizer/BioNTech mRNA vaccine elicits high levels of neutralizing antibodies and suggests many people could continue to have potent protection against the virus even if it changes.
They noted that the long T-follicular helper cell provides protection, the better it will be because antibodies will have a better memory of the virus and proper response against it. This is perhaps why the mRNA vaccine continues to provide strong protection against the virus.
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