COVID-19 Vaccine

Covid-19 Vaccine Resources

Updated on October 28, 2021

FAQ: COVID-19 Vaccine Booster Dose and Third Dose

On Monday, October 25, 2021 the CDC published an update to the Interim Clinical Considerations for Use of COVID-19 Vaccines with a focus on Booster Dose. Below are answers to commonly asked questions.

Q1. Which Pfizer and Moderna vaccine recipients are eligible for a COVID 19 booster dose?

The following should get a COVID-19 vaccine booster dose at least 6 months or more after their second dose of mRNA vaccine:

  • People aged 65 years and older
  • Residents aged 18 years and older in long-term care settings
  • People aged 50-64 years with underlying medical conditions

The following may get a COVID-19 vaccine booster dose at least 6 months or more after their second dose of mRNA vaccine, if you and/or your doctor feel it would benefit you based on your individual benefits and risks:

Q2. Which Johnson & Johnson (Janssen) recipients are eligible for a COVID 19 booster dose?

The following should get a COVID-19 vaccine booster dose at least 2 months or more after their dose of J&J vaccine:

  • People aged 18 years and older

Q3. Why was an additional booster dose recommended?

All currently available COVID-19 vaccine series (one shot of J&J/Janssen or two shots of Pfizer or Moderna) continue to offer strong protection against severe COVID-19 disease. Recent studies have shown that protection against the virus may decrease over time, particularly in certain populations, such as the elderly. In order to increase protection to those most vulnerable, a booster dose was recommended for certain higher risk groups.

Q4. What is the difference between “additional dose” vs. “booster dose”?

  • Additional dose after a primary series: An additional dose of vaccine is administered when the initial immune response following a primary vaccine series is likely to be insufficient. For example, a third dose of COVID-19 mRNA vaccine in certain immunocompromised
  • Booster dose: Initial immune response to a primary vaccine series is thought to be adequate (for example, in immunocompetent individuals). But an additional dose of vaccine is administered when the initial immune response to a primary series is likely to have waned over

Q5. Are the side effects similar for the booster dose?

Yes. To date, the side effects reported after a booster dose for all US-authorized COVID-19 vaccines seem to be similar to what people experienced after receiving doses 1 and/or 2. Pain at the injection site was the most commonly reported side effect. Most symptoms were mild to moderate and resolved within 3 days.

Q6. What are the eligible underlying medical conditions for mRNA booster eligibility per CDC?

Underlying medical conditions include but are not limited to:

Active cancer or history of cancer, chronic kidney disease, chronic lung disease(including COPD, moderate to severe asthma, interstitial lung disease, cystic fibrosis, pulmonary hypertension), dementia or other neurological conditions (such as Alzheimer’s), Type 1 or 2 diabetes mellitus, down syndrome, heart conditions (such as heart failure, coronary artery disease, cardiomyopathies, hypertension), HIV infection, liver disease, overweight and obesity (ie: BMI > 25), pregnancy, sickle cell disease or thalassemia, current or former smoking, stroke or cerebrovascular disease, mental health illness and substance use disorders.

Click here for more detail on underlying medical conditions at risk of severe illness.

Q7. What are the occupations at risk of exposure and/or transmission of COVID-19 eligible for mRNA booster dose?

The list includes frontline essential workers and healthcare workers.

  • First responders (healthcare workers, firefighters, police, congregate care staff)
  • Education staff (teachers, support staff, daycare workers)
  • Food and agriculture workers
  • Manufacturing workers
  • Corrections workers
  • U.S. Postal Service workers
  • Public transit workers
  • Grocery store workers

Click here for more details on Pfizer COVID-19 Vaccine booster.

Q8. I am immunocompromised and received a third dose of Pfizer vaccine already. Do I get an additional booster dose?

No. Pfizer or Moderna recipients who are severely immunocompromised should have already received a third dose of Pfizer or Moderna COVID-19 vaccine at least 28 days or more from their second dose of Pfizer COVID-19 Vaccine. If you have not done so, you should do so now. An additional booster dose after that third will not be due until 6 months after your third dose.

Q9. I am immunocompromised and have not received an additional dose of vaccine. Do I get a booster dose?

If you received Pfizer as your initial series, you should get a third dose of the same dosage at least 28 days after your second dose. If you received Moderna as your initial series, you should get a third dose of the same dosage (not the booster half-dose) at least 29 days after your second dose. If you received J&J vaccine initially, you should get your booster dose at least 2 months after your first shot.

Q10. Who is considered severely immunocompromised and eligible for mRNA COVID 19 vaccine (ie: Pfizer or Moderna) third dose?

  • Active treatment for solid tumor and hematologic malignancies
  • Receipt of solid-organ transplant and taking immunosuppressive therapy
  • Receipt of CAR-T-cell or hematopoietic stem cell transplant (within 2 years of transplantation or taking immunosuppression therapy)
  • Moderate or severe primary immunodeficiency (e.g., DiGeorge syndrome, Wiskott-Aldrich syndrome)
  • Advanced or untreated HIV infection (ie: CD4 count < 200)
  • Active treatment with high-dose corticosteroids (i.e., ≥20mg prednisone or equivalent per day), alkylating agents, antimetabolites, transplant-related immunosuppressive drugs, cancer chemotherapeutic agents classified as severely immunosuppressive, tumor-necrosis (TNF) blockers, and other biologic agents that are immunosuppressive or immunomodulatory.

Click here for more information.

Q11. Can I stop wearing masks and social distancing if I get the booster dose?

While the booster dose of the vaccine may provide added protection, it is still recommended that you continue to follow state and local guidance as it relates to wearing a mask, maintaining social distance, hand hygiene, etc.

Q12. Where can I get the COVID-19 vaccine?

If you wish, you may be vaccinated at one of our hospital locations. You can also check https://vaxfinder.mass.gov/ to find a vaccine clinic more convenient to you.

Q13. Do I need a note from my doctor to get a booster?

No. You do not need a doctor’s note to receive a booster dose. You may be required to attest that you meet eligibility criteria to receive a booster.

Q14. Do I need to bring my COVID-19 vaccine documentation when I get the booster shot?

We encourage you to bring your original vaccine card or documentation but it is not a requirement.

Q15. Is it okay to get the flu vaccine and the COVID-19 vaccine at the same time?

Yes. It is okay to get the influenza vaccine with any other recommended vaccines, including the COVID- 19 vaccine.

Q16. I have been fully vaccinated with the Pfizer primary series and later had a COVID-19 breakthrough infection. Since often COVID-19 infections offer additional immunity, do I still need a Pfizer COVID-19 vaccine booster?

At this time, CDC has no specific recommendations for this particular clinical scenario due to lack of data. But they are collecting data as quickly as possible to be able to answer this question with more certainty. That being said, we know that overall the likelihood of re-infection after being infected with COVID-19 is low and it becomes even lower if you were fully vaccinated prior to being infected. This is because it is likely that the infection acts as a natural “booster” of your immune system, hence further prolonging protection against re-infection. We also know that to date there has been no reports of re- infections in individuals who were fully vaccinated and then developed breakthrough COVID 19 infection. Based on this it is reasonable to wait at least 90 days after COVID 19 breakthrough infection and/or until more data becomes available.

Q17. Should I get a COVID-19 booster dose from the same vaccine brand as my primary series?

The FDA and CDC now allow for the receipt of any brand of vaccine as a booster for those who are eligible, regardless of the brand of the primary series. There are no clinical trial data to inform which combination is most effective.

Q18. Are there any populations in which specific mix-and-match combinations would be preferred?

  • Women under 50 requesting a booster dose of J&J should be counseled about the risk of TTS and offered mRNA vaccine. They may choose to proceed with J&J.
  • Men under 30 requesting a booster dose of mRNA vaccine should be counseled about the risk of myocarditis and offered J&J vaccine. They may choose to proceed with mRNA vaccine.

Q19. Is a mix-and-match approach acceptable for the 2nd or 3rd doses or only for the booster?

A mix-and-match approach is only approved for the booster dose. 2nd doses of mRNA vaccine should be the same brand as the first. 3rd doses for the immunocompromised should be the same dose as the first.

20 Things to Know About the COVID-19 Vaccine

The Covid-19 pandemic has been a stressful and often frightening time for many people, including those working on the frontlines. The new COVID-19 vaccine is a much anticipated and exciting next step in our fight against COVID-19. It is natural, as with any new medication or treatment, that people have questions about it. In the age of social media, it is easy for misinformation to spread quickly, and we want you to have your questions answered accurately and honestly. View the common questions about the COVID-19 vaccine and answers from Wellforce’s Infectious Disease experts.

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