Booster Shots, Third Doses and Boosted Doses for COVID-19 Vaccines — What You Need to Know

Featured Experts:

  • Dr. Maragakis

  • Dr. Gabor Kelen

Updated on January 28, 2022

COVID-xix vaccine boosters and additional vaccine doses are now authorized by the U.S. Food and Drug Assistants (FDA) and recommended by the U.South. Centers for Disease Control and Prevention (CDC) for most people, equally before long as they are eligible.

Lisa Maragakis, Thou.D., M.P.H., senior director of infection prevention, and Gabor Kelen, Thou.D., director of the Johns Hopkins Office of Critical Issue Preparedness and Response, explain what y'all need to know nearly these COVID shots.

What is a COVID-19 vaccine booster?

A COVID booster shot is an additional dose of a vaccine given later 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.

Why exercise I need a booster, since the COVID-xix vaccines are effective?

The protection offered by the FDA-approved and authorized vaccines is very powerful, but it starts to weaken after two months for the Johnson & Johnson vaccine, and after 5 months for the Pfizer and Moderna vaccines. Getting a booster shot extends the protection, even against the delta and omicron variants.

Two studies released past the CDC (one conducted April–December 2021 and the other from Baronial 2021–January 2022) evidence that being fully vaccinated (getting both doses of the Pfizer or Moderna vaccine or i Johnson & Johnson vaccine) plus receiving a booster provides greater protection from astringent illness, hospitalization and death due to COVID-19 compared to merely being fully vaccinated. A tertiary written report, published in the Periodical of the American Medical Association, shows similar results. The research also indicates that the booster offers greater protection confronting the delta and omicron variants than existence fully vaccinated or not vaccinated at all.

The CDC recommends that people who are vaccinated get a booster dose when they are eligible, and that they stay up to appointment with COVID-xix vaccinations.

Who can get a COVID-19 vaccine booster?

The CDC recommends a COVID-19 booster if you are:

  • Age eighteen or older and y'all received the Janssen-Johnson & Johnson vaccine at least 2 months ago
  • Age 18 or older and y'all received both required doses of the Moderna vaccine at least five months ago (your booster volition be a 1-one-half dose)
  • Age 12 or older and you received both required doses of the Pfizer-BioNTech vaccine at least five months agone (the Pfizer-BioNTech vaccine is the only vaccine and booster authorized for children and teens ages 12–17)
  • The CDC recommends that you get vaccinated and additional fifty-fifty if you lot previously had COVID-19 infection. Earlier getting a shot, be sure you have followed isolation and quarantine guidelines so you lot practise not infect others, and discuss your COVID-19 history with the medical team.

What are COVID booster side effects?

Afterward getting vaccinated for COVID-xix, you might experience some temporary symptoms like to those you lot might notice when yous get a flu shot, such as a sore, swollen arm where you got the shot. You might run a fever and feel torso aches, headaches and tiredness for a day or 2. Chills, swollen lymph nodes can also occur.

These symptoms exercise not hateful you are sick. They signal that your allowed system is responding to the shots and building up protection against the coronavirus.

Should I get an additional COVID-nineteen vaccine dose if I accept a weakened immune system?

People who have a medical condition associated with immunosuppression are eligible to get an additional vaccine dose.

This additional dose is given to people with moderately or severely compromised immune systems to improve their response to the initial vaccine series.

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

A COVID-nineteenbooster is given when a person has completed their vaccine serial, and protection against the virus has decreased over time. Depending on the original serial you had, some details will vary. Please review the booster eligibility information above and talk to your health care provider if you lot are non sure if y'all meet these guidelines. Please note, if you receive the Moderna booster, you will receive half of the original Moderna dose.

Anadditional dose is administered to people with moderately to severely compromised allowed systems. This additional dose is intended to improve immunocompromised people'southward response to their initial vaccine series. Depending on the original series given, some details will vary. Please review the additional dose eligibility data and talk to your health care provider if you are not sure if you encounter these guidelines.

Who can get an additional dose of a COVID-nineteen vaccine?

The CDC and the FDA recommend an boosted dose when eligible for those who are immunocompromised and ages five and older. This includes those who:

  • Take been receiving active cancer treatment for tumors or cancers of the blood
  • Received an organ transplant and are taking medicine to suppress the immune system
  • Received a stem cell transplant within the last two years, or are taking medicine to suppress the immune system
  • Are diagnosed with moderate or severe primary immunodeficiency (such as DiGeorge syndrome or Wiskott-Aldrich syndrome)
  • Are diagnosed with HIV and take a high viral load or depression CD4 count, or are not currently taking medication to treat HIV
  • Are taking drugs like high-dose steroids or other medications that may crusade astringent suppression of the immune system

The CDC as well recommends a booster shot three months after the additional primary shot for those who received the Pfizer or Moderna vaccine, and ii months afterwards the one-shot Johnson & Johnson vaccine.

If you are not sure whether y'all fit into any of these categories, please contact your medical provider. For more details, delight review the CDC'south information for moderately to severely immunocompromised people.

When should I get an boosted dose of COVID-19 vaccine?

If you are immunosuppressed and originally received the Moderna or Pfizer COVID-nineteen vaccine, you lot can get an additional dose when information technology has been at least 28 days since your second shot.

If you got the Janssen/Johnson & Johnson COVID-xix vaccine, yous tin get an additional dose when it has been at least two months since your vaccine.

Does my COVID-19 booster or additional dose accept to be the aforementioned brand that I got before?

No, y'all can mix and match brands. The FDA has authorized 3 vaccine boosters — Pfizer-BioNTech, Moderna and Janssen-Johnson & Johnson — and determined that it is rubber to become a COVID-19 vaccine booster or boosted dose that is a different make than your initial dose or doses.

The Pfizer-BioNTech vaccine and booster are the only ones authorized for children and teens ages 12–17.

If you get the Moderna booster, you will receive half of the original Moderna dose. Please be certain to confirm this with the person giving yous the shot.

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COVID-19 Vaccine

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