How do the COVID-19 vaccines work?

mRNA vaccines, like Moderna or Pfizer's Comirnaty, contain material from the virus that causes COVID-19 that gives our cells instructions for how to make a harmless protein that is unique to the virus. After our cells make copies of the protein, they destroy the genetic material from the vaccine. Our bodies recognize that the protein should not be there and build defensive cells that will remember how to fight the virus that causes COVID-19 if we are infected in the future.

Vector vaccines, like Johnson and Johnson (Janssen), contain a modified version of a different virus than the one that causes COVID-19. Inside the shell of the modified virus, there is material from the virus that causes COVID-19. This is called a viral vector. Once the viral vector is inside our cells, the genetic material gives cells instructions to make a protein that is unique to the virus that causes COVID-19. Using these instructions, our cells make copies of the protein. This prompts our bodies to build specialized cells that will remember how to fight that virus if we are infected in the future.

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1. Why should I get vaccinated?
2. Will I have to pay for the vaccine?
3. Will I be asked about my immigration status?
4. When am I considered fully vaccinated?
5. I've had COVID-19. Do I still need to get vaccinated?
6. Are COVID-19 vaccines safe?
7. Can I be vaccinated if I'm pregnant or breastfeeding?
8. Have the vaccines been tested?
9. What are the common side effects of COVID-19 vaccines?
10. How do the COVID-19 vaccines work?
11. Are COVID-19 vaccines likely to have long-term side effects?
12. Will the vaccine alter my DNA?
13. Will the vaccine make me sick with COVID or make me test positive?
14. Are there serious side effects from COVID-19 vaccines?
15. What if I experience a side effect after being vaccinated?
16. Will the vaccine make me magnetic?
17. What ingredients are in COVID-19 vaccines?