COVID-19: Additional and Booster Doses

Adult wearing a mask supporting: You Stop the Spread

Booster doses and additional doses serve different purposes for different groups of people.

People who are moderately to severely immunocompromised are recommended to get an additional dose of an mRNA COVID-19 vaccine (Pfizer or Moderna) no sooner than 28 days after their initial two-dose mRNA COVID-19 vaccine series.

People aged 65 years and older, residents in long-term care settings, people aged 50–64 years with underlying medical conditions, and other groups at high risk are eligible to get a Pfizer booster dose at least six months after completing their two-dose primary series of Pfizer. 

While vaccination remains the most effective tool we have to prevent COVID-19, everyone should continue to practice good public health behavior. This means wearing a mask indoors, avoiding large gatherings, staying home when feeling sick, and getting testing if you have symptoms or after close contact.   
 

DHS supports the U.S. Food and Drug Administration's (FDA) authorization and Centers for Disease Control and Prevention's (CDC) recommendation to provide Pfizer booster doses to certain populations.

Booster doses

A “booster dose” is a supplemental vaccine dose given to people when the immune response to a primary vaccine series is likely to have decreased over time. The primary COVID-19 vaccination series continues to be highly effective at reducing severe disease, hospitalization, and death caused by COVID-19. However, experts are beginning to see that protection against mild to moderate disease can fade over time. The booster dose is intended to boost your immune system for better, long lasting protection. 

Who should get a booster dose? 

Those who are at highest risk for COVID-19 and have received the two-dose series of Pfizer vaccine are recommended to get a booster dose of Pfizer vaccine to help increase their protection against COVID-19. Many of the people that are now eligible for a booster dose completed their initial vaccine series early on in the vaccination rollout.

DHS recommends that the following populations should receive a booster dose of Pfizer at least six months after receiving their second dose of Pfizer in order to further strengthen their immunity: 

  • People 65 years and older
  • All residents in long-term care
  • People ages 50 to 64 years with certain underlying medical conditions
    • Cancer
    • Chronic kidney disease
    • Chronic lung diseases, including COPD (chronic obstructive pulmonary disease), asthma (moderate-to-severe), interstitial lung disease, cystic fibrosis, and pulmonary hypertension
    • Dementia or other neurological conditions
    • Diabetes (type 1 or type 2)
    • Down syndrome
    • Heart conditions (such as heart failure, coronary artery disease, cardiomyopathies or hypertension)
    • HIV infection
    • Immunocompromised state (weakened immune system)
    • Liver disease
    • Overweight and obesity
    • Pregnancy
    • Sickle cell disease or thalassemia
    • Smoking, current or former
    • Solid organ or blood stem cell transplant
    • Stroke or cerebrovascular disease, which affects blood flow to the brain
    • Substance use disorders
       

DHS recommends that the following populations may receive a booster dose of Pfizer at least six months after receiving their second dose of Pfizer for those who determine that a booster shot will further protect their health and the health of those around them: 

  • People ages 18 to 49 years with certain underlying medical conditions (listed above)
  • People ages 18 to 64 years who are at increased risk for COVID-19 exposure and transmission because of their job or institutional settings. Occupations at increased risk for COVID-19 exposure and transmission include front line essential workers and health care workers:
    • First responders (health care workers, firefighters, police, staff at congregate care facilities)
    • 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

At this time, the Pfizer booster authorization only applies to people whose primary series was Pfizer vaccine. People in the recommended groups who got the Moderna or Johnson & Johnson vaccine will likely need a booster shot in the near future. More data on the effectiveness and safety of Moderna and Johnson & Johnson booster shots are expected soon. 

Frequently asked questions about booster doses

Do I need to receive a booster or additional dose to be considered fully vaccinated?

No, people are considered fully vaccinated two weeks after you’ve received either a single-dose vaccine, like Johnson & Johnson, or the second dose of a two-dose vaccine, like Pfizer or Moderna.

My job isn’t on the list, but I feel at high risk of COVID-19. Can I get a booster?

People ages 18 to 64 who received the two-dose series of Pfizer vaccine at least six months ago and personally determine that a booster shot will further protect their health and the health of those around them due to exposure at their job may get a booster shot, even if their job is not listed on the CDC or DHS website. 


Additional doses

An “additional dose” is recommended for people who may not have received adequate protection from their initial vaccine series. On August 13, the FDA updated the emergency use authorizations (EUAs) for the Pfizer and Moderna COVID-19 vaccines to allow for additional doses to very specific groups of people. The additional dose can be administered any time, as long as it is at least 28 days after completing the initial two-dose mRNA COVID-19 vaccine series (such as for Pfizer and Moderna).

Who should get an additional dose?

Individuals with specific medical conditions or receiving medical treatments that cause them to be moderately to severely immunocompromised are recommended to get an additional dose of Pfizer or Moderna COVID-19 vaccine. Immunocompromised people have a reduced ability to fight disease, a lower immune response to the original vaccine series compared to other fully vaccinated people, and are especially vulnerable to COVID-19 infection. This includes people who have:

  • 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.
  • Moderate or severe primary immunodeficiency (such as DiGeorge syndrome, Wiskott-Aldrich syndrome).
  • Advanced or untreated HIV infection.
  • Active treatment with high-dose corticosteroids, alkylating agents, antimetabolites, transplant-related immunosuppressive drugs, cancer chemotherapeutic agents classified as severely immunosuppressive, tumor-necrosis (TNF) blockers, or other drugs that may suppress your immune response.

Even though the additional dose will be important to help prevent COVID-19 hospitalizations and death, immunocompromised people may still have a reduced immune response after getting the additional dose of the mRNA COVID-19 vaccine. This means, it is still important for immunocompromised people to take continue to follow current prevention measures (like wearing a mask and physical distancing) even after their additional mRNA COVID-19 vaccine dose.

Talk to your health care provider about:

  • whether you need to get an additional dose.
  • whether you will need to pause your treatment or medication before or after getting an additional dose of the vaccine.

If you don't have a health care provider, call 211 or text COVID to 211-211. Language assistance is available.

 

People who received a Johnson & Johnson COVID-19 vaccine are not recommended to receive an additional dose at this time because of limited data. The CDC and the FDA are monitoring the data and will make recommendations as needed.

Frequently asked questions about additional doses

What should immunocompromised people who received the Johnson & Johnson (Janssen) COVID-19 vaccine do?

At this time, only individuals with specific medical conditions or receiving medical treatments that cause them to be moderately to severely immunocompromised who received initially received an mRNA COVID-19 vaccine series (Pfizer or Moderna) are eligible for an additional dose.

The FDA and CDC are working to better understand the data on whether immunocompromised people who received the Johnson & Johnson (Janssen) COVID-19 vaccine also have an improved antibody response following an additional dose of the same vaccine.

The FDA and CDC are actively working to provide guidance on this issue.

Can you mix and match the mRNA vaccines?

The additional dose should be the same vaccine product as the initial two-dose mRNA COVID-19 vaccine series (Pfizer or Moderna). If you are 18 years or older and the mRNA COVID-19 vaccine product given for the first two doses is not available, you can get the other mRNA COVID-19 vaccine product that is available.

For example, if you received your first two doses of Pfizer COVID-19 vaccine but you cannot find a vaccine location that has Pfizer vaccine, you can get an additional dose of Moderna COVID-19 vaccine if you are 18 years or older. If you are immunocompromised and are younger than 18 years old, your additional dose has to be a dose of Pfizer COVID-19 vaccine.

This does not apply to booster doses. Only people who have received the two-dose series of the Pfizer vaccine are recommended to receive a booster dose of Pfizer.

If I am eligible for an additional dose, do I have to return to the same vaccination location where I got my first and second doses?

No, you can receive the additional dose wherever mRNA COVID-19 vaccines are offered. Try to make sure the vaccination location has the same kind of vaccine you received for your first two doses.

If possible, bring your white CDC COVID-19 vaccination card or a printed or downloaded summary of your immunization record.


Find a vaccination appointment

The vaccine is safe, effective, and free. You do not need an ID or insurance to get it There are several ways you can receive your COVID-19 vaccine. 

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Last Revised: October 8, 2021

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