CIANA Explains: COVID Booster Shots & Third Doses



There is some confusion over the difference between booster shots and third doses of the COVID-19 vaccine, as well as who can get them. We hope to clear up any confusion or misinformation below:


What is a third shot?

Third shots are offered to people with compromised immune systems 4 weeks after their second dose. Currently, only Moderna and Pfizer recipients can get a third shot.


What is a booster shot?

Booster shots are generally given 6 months after one's second dose, when the efficacy of the vaccine starts to decrease. Booster shots are offered to the following groups:

  • All adults ages 65 and up

  • Adults ages 18-64 working or living in high-risk environments of COVID-19 infection (e.g., food delivery workers or nursing home residents)

  • Adults ages 18-64 with pre-existing health conditions (e.g., diabetes or asthma)

Only Pfizer has been approved for booster shots by the FDA, so only those who received Pfizer for their first and second doses can get their booster shot at this time.


What's the difference?

The main differences have to do with who is getting their additional dose, when they get it, and how it protects your body from infection.


Moderna and Pfizer both offer third doses to immunocompromised individuals. As of October 22, all three vaccine brands- Moderna, Pfizer, and Johnson & Johnson- are approved to offer booster shots.


What if I received J&J?

People who received the Johnson & Johnson vaccine are now eligible for their booster shot as of October 22. Because the initial J&J vaccine is a single dose, the J&J booster will be a second shot, rather than a third.


How long should I wait before getting my booster shot?

The FDA and CDC have recommended receiving a booster shot at least 6 months after one's second dose of the Moderna or Pfizer vaccine. Those who received Johnson & Johnson can now get their booster shots at least 2 months after their initial dose. As with the original doses, the shot takes 2 weeks to go into full effect.


Do I have to get the same type of vaccine for my third shot/booster?

The update from the FDA allows individuals to "mix and match" their vaccines. For instance, a person who received Pfizer for their first two doses can get Moderna for their booster.


What about vaccines for children under age 12?

Pfizer has submitted data to the FDA on vaccines for children ages 5-11. While it may take at least a few weeks for the FDA to review the research, this is necessary to ensure vaccines will be safe and effective for young children. We will let you know when there has been an update.



If you're eligible for your booster or third shot, make an appointment at a vaccine site near you.


If you have any questions about eligibility for a third/booster shot, or need help finding a vaccine site or making an appointment, call CIANA at 718-545-4040 or email info@cianainc.org.



Note: This article was updated 10/26 to reflect changes regarding booster shot approval and availability.