NOTICE: CDC now recommends that people whose immune systems are compromised moderately to severely should receive an additional dose of mRNA COVID-19 vaccine after the initial 2 doses. Widespread vaccination is a critical tool to help stop the pandemic. Read CDC’s statement.
Cases of myocarditis and pericarditis in adolescents and young adults have been reported more often after getting the second dose than after the first dose of one of these two mRNA COVID-19 vaccines. These reports are rare and the known and potential benefits of COVID-19 vaccination outweigh the known and potential risks, including the possible risk of myocarditis or pericarditis.
Authorized and Recommended Vaccines
Currently, three vaccines are authorized and recommended in the United States to prevent COVID-19:
Pfizer-BioNTech
Moderna
Johnson & Johnson / Janssen

Different COVID-19 Vaccines
Vaccines are now widely available. In most cases, you do need an appointment. Do not wait for a specific brand. Learn how to find a COVID-19 vaccine so you can get it as soon as you can.
All currently authorized and recommended COVID-19 vaccines:
- are safe,
- are effective, and
- reduce your risk of severe illness.
CDC does not recommend one vaccine over another.
Vaccine Brand Name
Who Can Get this Vaccine [ 1 ]
How Many Shots You Will Need
When Are You Fully Vaccinated?
People 12 years and older
2 shots
Given 3 weeks (21 days) apart [ 2 ]
2 weeks after your second shot
People 18 years and older
2 shots
Given 4 weeks (28 days) apart [ 2 ]
2 weeks after your second shot
People 18 years and older
1 shot
2 weeks after your shot
1 If you have had a severe allergic reaction (anaphylaxis) or an immediate allergic reaction to any ingredient in the vaccine you are scheduled to receive, you should not get that vaccine. If you have been instructed not to get one type of COVID-19 vaccine, you may still be able to get another type. Learn more information for people with allergies.
2 You should get your second shot as close to the recommended 3-week or 4-week interval as possible. However, your second shot may be given up to 6 weeks (42 days) after the first dose, if necessary.
Vaccine Types
- Understanding How COVID-19 Vaccines Work
Learn how the body fights infection and how COVID-19 vaccines protect people by producing immunity. Also see the different types of COVID-19 vaccines that currently are available or are undergoing large-scale (Phase 3) clinical trials in the United States. - COVID-19 mRNA Vaccines
Information about mRNA vaccines generally and COVID-19 vaccines that use this new technology specifically. - Viral Vector COVID-19 Vaccines
Information about viral vector vaccines generally and COVID-19 vaccines that use this new technology specifically.