DEAR MAYO CLINIC: I know COVID-19 has been around now for over a year, but I'm still confused by the different types of vaccines, including messenger RNA and vector vaccines. Can you explain how these vaccines work and the differences between these vaccines?
ANSWER: COVID-19 vaccines can help you develop immunity to SARS-CoV-2, the virus that causes COVID-19, without getting ill. But how the different types of COVID-19 vaccines work is a question many people ask.
Vaccines prompt an immune response so that your body remembers how to fight a virus in the future. Some vaccines use a whole virus to cause your immune system to respond. Other vaccines use parts of the virus or genetic material that provides instructions for making specific proteins like those in the virus.
Many COVID-19 vaccines involve a spikelike structure on the surface of the COVID-19 virus called an S protein. The S protein helps the virus get inside your cells and start an infection.
Manufacturers around the world are working on different types of vaccines. The main types of COVID-19 vaccines available in the U.S. or in large-scale clinical trials are:
The Food and Drug Administration (FDA) has granted emergency use authorization for the J&J, Moderna and Pfizer COVID-19 vaccines. the AstraZeneca COVID-19 vaccine has not yet been granted emergency use authorization.
The FDA and the Centers for Disease Control and Prevention have recommended that use of the J&J vaccine continue in the U.S. because the benefits outweigh the risks. If you are given this vaccine, you should be educated about the possible risks and symptoms of a blood clotting problem.
More types of COVID-19 vaccines are expected to be authorized for use over the coming months.
Being vaccinated for COVID-19 might prevent you from getting COVID-19, or from becoming seriously ill or dying due to COVID-19. Consult your local health department for the latest information on how and when you can receive a vaccine. — Compiled by Mayo Clinic Staff
Information in this post was accurate at the time of its posting. Due to the fluid nature of the COVID-19 pandemic, scientific understanding, along with guidelines and recommendations, may have changed since the original publication date.
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