Health
a health care provider prepares a vaccine for a mature woman
a health care provider prepares a vaccine for a mature woman
a health care provider prepares a vaccine for a mature woman

Booster Shots and Additional Doses for COVID-19 Vaccines — What You Need to Know

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Updated September 26, 2022

As of Sept. 2, 2022, the CDC recommends a bivalent (containing components of both the original strain of the SARS-CoV-2 virus and the omicron variant of the virus) COVID-19 booster for people aged 12 years and older (Pfizer) or 18 years and older (Moderna). The bivalent vaccines, which offer better protection against COVID-19 caused by the omicron variant than the earlier, monovalent vaccines, have been authorized for use as a single booster dose administered at least two months after primary or booster vaccination. The monovalent COVID-19 vaccines will no longer be available for booster doses in patients over the age of 12. However, the monovalent vaccines will remain available for the primary vaccine series in all patients and for booster doses in patients younger than 12 years old.

Johns Hopkins Medicine has the bivalent COVID-19 booster.

Please read the CDC’s guidelines for individuals who are not moderately or severely immunocompromised.

Please read the CDC’s guidelines for individuals who are moderately or severely immunocompromised.

What is a COVID-19 vaccine booster?

A COVID booster shot is an additional dose or doses of a vaccine given after the protection provided by the original shot(s) has begun to decrease over time. The booster helps people maintain strong protection from severe coronavirus disease.

What are COVID booster side effects?

After getting vaccinated for COVID-19, you might experience some temporary symptoms similar to those you might notice when you get a flu shot, such as a sore, swollen arm where you got the shot. You might run a fever and experience body aches, headaches and tiredness for a day or two. Chills, swollen lymph nodes can also occur.

These symptoms do not mean you are sick. They signal that your immune system is responding to the shots and building up protection against the coronavirus.

Where can I get a COVID-19 vaccine booster?

Please check your state or local resources. Retail pharmacies, mobile vaccination clinics (walk-up) and state and local vaccination sites offer booster appointments. Some locations may offer walk-up vaccination times.

Should I get an additional COVID-19 vaccine dose if I have a weakened immune system?

Yes, the CDC has approved an additional dose for individuals who are moderately to severely immunosuppressed. Please read the CDC’s guidelines for individuals who are moderately or severely immunocompromised.

What is the difference between a booster and an additional dose?

A COVID-19 booster is given when a person has completed their vaccine series, and protection against the virus has decreased over time. Depending on the original series you had, some details will vary. Please review the CDC’s booster guidelines for details and talk to your health care provider if you are not sure if you meet these guidelines. Please note, if you receive the Moderna booster, you will receive half of the original Moderna dose.

An additional dose is administered to people with moderately to severely compromised immune systems. This additional dose is intended to improve immunocompromised people’s response to their initial vaccine series. Depending on the original series given, some details will vary. For more details, please review the CDC’s information for moderately to severely immunocompromised people and talk to your health care provider if you are not sure if you meet these guidelines.

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COVID-19 Vaccine

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