How do COVID-19 vaccines work?
The vaccines work by teaching your body’s immune system to recognize the virus that causes COVID-19. This allows your body to fight off the virus if it ever encounters it. Vaccines can reduce the severity of disease if you become infected, and they may also help to prevent transmission of the virus to others. In the case of COVID-19, two types of vaccines are available: viral vector-based vaccines (AstraZeneca and Johnson & Johnson) and mRNA vaccines (Pfizer–BioNTech and Moderna). Viral vector vaccines use a different, harmless virus to introduce bits of the COVID-19 virus, without making you sick, to cause the body to produce antibodies against COVID-19. On the other hand, mRNA vaccines directly teach your cells to produce a protein that then triggers an immune response. You can learn about mRNA vaccines and HIV in this CTN blog post.