The FDA has approved three versions of the COVID-19 vaccine for use. These include Pfizer-BioNTech, Moderna, and Johnson & Johnson/Janssen. While once limited in quantity, COVID-19 vaccines are now available to all individuals aged 12 and older.
All vaccines, apart from the Johnson & Johnson vaccine, initially required that two shots be administered, with booster shots as a recommendation for some. Who is eligible to receive a booster shot, and is it safe to mix COVID-19 vaccines?
Only certain individuals are eligible for a COVID-19 booster shot at this time
If you received the Johnson & Johnson or Moderna COVID-19 vaccine, the Centers for Disease Control and Prevention (CDC) says you aren’t eligible for a booster shot (of the same kind) at this time. However, this might change after a federal advisory group recommended that both Johnson & Johnson and Moderna booster shots be approved, according to The New York Times.
If you received the Pfizer-BioNTech vaccine, which is administered in two doses, 21 days apart, it's recommended that you wait at least six months before receiving a booster shot. While the FDA and CDC recommend individuals who received the Pfizer COVID-19 vaccine also receive the Pfizer booster shot (clinical trials have shown it increases your immune response to the virus), the vaccine isn’t available to everyone.
Only certain populations are eligible to begin receiving a Pfizer-BioNTech COVID-19 booster shot. These include:
- Adults between the ages of 50 and 64 who have an underlying health issue.
- Long-term care residents age 18 and older.
- Individuals with medical issues between the ages of 18 and 49.
- Anyone between the ages of 18 and 64 who is at increased risk of COVID-19 exposure and transmission. This includes first responders, educators, and U.S. Postal Services workers.
Here's what research shows on mixing COVID-19 vaccines
While the FDA and CDC recommend individuals follow up their initial COVID-19 vaccine with a booster shot of the same kind, the FDA is reportedly “planning to allow Americans to receive a different COVID-19 vaccine as a booster from the one they initially received.”
According to a study, those who initially received the Johnson & Johnson vaccine “saw their antibody levels rise 76-fold in 15 days after receiving the Moderna booster shot.” The New York Times said the study also showed that those who initially received a Johnson & Johnson vaccine and followed it up with a booster of the same kind only saw a “fourfold increase in their antibody levels.”
The New York Times reported the FDA is expected to authorize the use of boosters for both Moderna and Johnson & Johnson by Oct. 21, and possibly allow individuals to mix COVID-19 vaccines. If the CDC and FDA approve the “mix and match” method, millions of Americans might become eligible for a booster shot.
What's the purpose of a COVID-19 vaccine booster shot?
COVID-19 vaccine booster shots are administered after you complete your vaccine series. If you received two Moderna vaccines or one Johson & Johnson vaccine, you are considered fully vaccinated. Booster shots are created to help you “maintain [your] level of immunity for [longer].”
Over time, the COVID-19 vaccine, whether it is administered in one, two, or even three doses, might become less effective at protecting you.