How does the covid vaccine work?
The COVID-19 vaccines work by teaching the immune system how to recognize and fight the coronavirus without causing the illness. There are currently multiple types of COVID-19 vaccines, including those developed by Pfizer-BioNTech, Moderna, and AstraZeneca/Oxford.
mRNA vaccines, such as the Pfizer-BioNTech and Moderna vaccines, use messenger RNA (mRNA) to deliver instructions to the cells in our body. The mRNA carries the genetic code for the spike protein found on the surface of the coronavirus. Once the mRNA is injected, our cells use this information to temporarily produce the spike protein. This spike protein triggers an immune response, as our immune system recognizes it as foreign. Immune cells then generate an immune response to destroy the spike protein. If we later encounter the actual coronavirus, our immune system will now recognize it and fight it off more effectively.
Vector-based vaccines, like the AstraZeneca/Oxford vaccine, use a harmless virus (not the coronavirus) as a vector to deliver a piece of the genetic material of the coronavirus into our cells. This genetic material encodes the spike protein. Once inside our cells, the genetic material instructs them to produce the spike protein. Similar to mRNA vaccines, this triggers an immune response and builds up immunity against the coronavirus.
Both types of vaccines stimulate the immune system to produce antibodies and activate immune cells, such as T-cells, which remember the virus if encountered again in the future. This helps protect against severe illness or complications from COVID-19.
It's important to note that while the vaccines greatly reduce the risk of severe illness and hospitalization, they do not guarantee complete protection against COVID-19. Therefore, continuing to follow preventive measures, such as wearing masks, practicing physical distancing, and washing hands regularly, is advised even after vaccination.