The protection against disease that vaccines provide may start to wane over time. In these cases, a booster dose may be needed to boost a person’s immune response and increase protection. While the COVID-19 vaccines continue to be remarkably effective in reducing risk of severe disease, hospitalization, and death, data from the U.S. and around the world show that a booster is required for some people to maintain the vaccine’s maximum effectiveness in preventing infection.
Based on data for each of the COVID-19 vaccines, the CDC recommends booster shots for some groups of people:
- Some Pfizer and Moderna recipients:
- Adults age 65 and over, and those living in long-term care facilities, should get a booster.
- Adults ages 50-64 at high risk of severe COVID-19 due to underlying medical conditions should get a booster.
- Adults ages 18-49 at high risk of severe COVID-19 due to underlying medical conditions may get a booster, based on an assessment of their individual benefits and risks and consultation with their medical provider.
- Adults age 18-64 for people whose jobs put them at high risk for COVID-19 may get a booster — including health care workers, teachers, daycare staff, grocery workers, and other essential workers, along with people in shelters and prisons.
The booster dose should be administered at least six months after the second Pfizer or Moderna dose, and any available COVID-19 vaccine can be administered as a booster regardless of the primary series. A half dose of the initial Moderna vaccine will be administered for the Moderna booster.
- All Johnson & Johnson recipients age 18 and older should get a booster at least two months after their initial shot. Any available COVID-19 vaccine (including Pfizer or Moderna) can be administered as a booster dose for Johnson & Johnson recipients.
Updated October 22, 2021