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Frequently Asked Questions About the COVID-19 Vaccine

​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​Click below to get answers to common questions about the COVID-19 vaccine. 

Are the vaccines safe?

• Yes. Over 500 million vaccine doses have been safely administered in the US with only rare vaccine-related health effects. The benefits of vaccination greatly outweigh the risks.

The Comirnaty (Pfizer) and Moderna vaccines have been linked to an increased risk of myocarditis (heart inflammation) in teens and young adults, especially in males. Myocarditis is very rare—about 13 cases per million after dose 2 in the Vaccine Safety Datalink (including data from Marshfield Clinic). Most myocarditis cases have been mild.

The Janssen vaccine has been linked to two rare but serious problems: an increased risk of serious blood clots with low platelets (called TTS), and a rare neurologic disease called Guillain-Barre Syndrome (GBS). The overall risk of blood clots is about 3 cases per million doses of Janssen vaccine in adults, with a higher risk in women. For GBS, the overall risk is about 8 cases per million doses. On December 16, 2021, the CDC’s Advisory Committee on Immunization Practices expressed a clinical preference for individuals to receive an mRNA COVID-19 vaccine (Pfizer or Moderna) over the Janssen (Johnson & Johnson) COVID-19 vaccine due to the increased risk of TTS.

The CDC has assessed the risks and benefits of each vaccine, concluding that the benefits (preventing COVID-19 hospitalization and death) are substantial and greatly outweigh the low risk of a vaccine-related complication. The COVID-19 vaccines also are highly effective against the delta variant that is spreading rapidly among unvaccinated people. Everyone who receives a COVID-19 vaccine should be aware of the risks and benefits to make an informed choice.

Are the vaccines effective?

Our nationally-recognized infectious disease providers and epidemiologists agree with other experts that the vaccines:

• Have benefits (preventing COVID-19 hospitalization and death) that are substantial and greatly outweigh the low risk of a vaccine-related complication.

• Are effective at preventing COVID-19.

• The mRNA vaccines are highly effective for preventing serious illness caused by the delta variant.

How were the vaccines developed so quickly?

• Basic scientific research over two decades led to breakthroughs and proof that mRNA and viral vector vaccines can generate immunity. Clinical trials were overlapped to shorten the timeline, cutting out much of the red tape in the process. Production of the vaccine also occurred before clinical trials were completed. The federal government provided financial support to speed up vaccine development. The FDA was then able to give the vaccine emergency use authorization based on strong evidence that vaccine benefits outweigh risks.

Is there a booster shot for the COVID-19 vaccine?

• Individuals 16 years and older are eligible for a booster dose. Booster doses should be administered two months after the a primary dose of Janssen (Johnson and Johnson), or six months after primary series of Comirnaty (Pfizer-BioNTech) or Moderna.

   o Individuals 16 and 17 years old must receive Pfizer-BioNTech as a booster dose.

   o Individuals 18 years and older may choose which vaccine they receive as a booster dose. Some people may have a preference for the vaccine type that they originally received and others may prefer to get a different booster. This type of mix and match dosing for booster shots is allowed for 18 years and older.

• Mix and match dosing is not allowed for additional primary doses given to immunocompromised individuals. People who are immunocompromised continue to be eligible to receive an additional dose of the Comirnaty (Pfizer-BioNTech COVID-19 vaccine) or Moderna COVID-19 vaccine 28 days after the completion of their initial series of Comirnaty (Pfizer-BioNTech COVID-19 vaccine) or Moderna COVID-19 vaccine.

Does the vaccine cause infertility?

• There is no evidence that the COVID-19 vaccine causes infertility. Researchers studied fertility in animals for each of the COVID-19 vaccines. The research found that the COVID-19 vaccines did not affect fertility in the animals. The research also found that the COVID-19 vaccines did not cause any issues with the development of the babies while in the womb. A letter by two anti-vaccination bloggers fueled the rumors about infertility.

• Participants in the vaccine trials were asked to avoid getting pregnant. Despite this, there were at least 23 pregnancies in women who received the Pfizer vaccine.

Do any COVID-19 vaccines have full FDA approval?

• On Aug. 23, 2021, FDA approved Comirnaty (COVID-19 Vaccine, mRNA), which was previously known as Pfizer-BioNTech COVID-19 Vaccine, for the prevention of COVID-19 disease in individuals 16 years of age and older.

• On Feb. 1, 2022, FDA approved Spikevax (COVID-19 Vaccine, mRNA), which was previously known as Moderna COVID-19 Vaccine, for the prevention of COVID-19 disease in individuals 18 years of age and older.

Is natural infection from COVID-19 better than an actual vaccine?

• No. Natural infection has already caused more than 600,000 deaths, and the number of deaths and hospitalizations is increasing among unvaccinated people due to the delta variant. You should receive the vaccine even if you already had COVID-19. People who complete the COVID-19 vaccine series have a high level of protection against infection and serious illness, including serious illness caused by the delta variant. Vaccination after natural infection generates a strong boost in antibody levels, and a CDC study found that people who are vaccinated after COVID-19 have a reduced risk of reinfection compared to people who were previously infected and unvaccinated.

Do I need to continue wearing a mask after I get the vaccine?

• Fully vaccinated people can resume activities without wearing masks or physically distancing, except where required, including local business, school and workplace guidance. However, CDC recommends everyone should wear a mask indoors in public in substantial or high transmission areas.

• Fully vaccinated individuals can refrain from quarantine following exposure, but should be tested 3-5 days and wear a mask in public indoor spaces for 14 days following exposure. More details found on CDC website.

What are the ingredients of the vaccines?

• Comirnaty (Pfizer) ingredients include: mRNA, lipids, cholesterol, potassium chloride, monobasic potassium phosphate, sodium chloride, dibasic sodium phosphate dihydrate and sucrose.

• Moderna ingredients include: mRNA, lipids (including polyethylene glycol), cholesterol, potassium chloride, monobasic potassium phosphate, sodium chloride, dibasic sodium phosphate dihydrate and sucrose.

• Janssen (Johnson & Johnson) ingredients include recombinant, replication-incompetent adenovirus type 26 expressing the SARS-CoV-2 spike protein, citric acid monohydrate, trisodium citrate dihydrate, ethanol, 2-hydroxypropyl-β-cyclodextrin (HBCD), polysorbate-80 and sodium chloride.

How many doses of the COVID-19 vaccine will I need to get?

The below recommendations are for individuals 16 and older:

• The initial series of the Comirnaty (Pfizer) vaccine is given in two doses, three weeks apart. An additional primary dose is recommended 28 days later for immunocompromised individuals. A booster dose is recommended six months after the completion of the primary series or additional primary dose.

• The initial series of the Moderna vaccine is given in two doses, four weeks apart. An additional primary dose is recommended 28 days later for immunocompromised individuals. A booster dose is recommended six months after the completion of the primary series or additional primary dose.

• The Janssen (Johnson & Johnson) COVID-19 vaccine is a single dose vaccine. A booster dose is recommended two months after the initial dose.

• Individuals age 5-15 are not eligible for booster doses of the COVID-19 vaccine. Individuals age 12-15 who are immunocompromised are eligible for additional primary doses of the COVID-19 vaccine. Individuals four and younger are not eligible for the COVID-19 vaccine.

Will I have to pay for the COVID-19 vaccine?

• No one who receives the COVID-19 vaccine will have to pay out-of-pocket costs for the vaccine. Vaccine administrators will not deny anyone vaccination based on the vaccine recipient’s coverage status or network status. Learn more here.

Can children receive a COVID-19 vaccine?

• Yes, CDC recommends everyone ages 6 months and older get vaccinated against COVID-19.
• Children ages 6 months-4 years are eligible for the pediatric Pfizer-BioNTech, which is given in three doses. The first and second doses are separated by 21 days and the second and third doses are separated by at least 56 days.

• Children ages 6 months-4 years also are eligible for the pediatric Moderna COVID-19 vaccine, which is given in two doses 28 days apart.

• Children ages 5-11 are eligible for the pediatric Pfizer-BioNTech COVID-19 vaccine, which is given in two doses 21 days apart. These vaccine above are a smaller dose than the adult version of the COVID-19 vaccines. This is due to the fact that children are generally more responsive to vaccines and they are smaller in size.

• Adolescents age 12-17 are eligible for the Pfizer-BioNTech COVID-19 vaccine, which is given in two doses 21 days apart. This vaccine is the same dose given to adults.

Have more questions?

The Centers for Disease Control and Prevention provide answers to commonly ask​ed questions about COVID-19 vaccination

  Click here  


Accurate COVID-19 vaccine information is important. CDC also has answers to common myths and rumors.​

  Click here  ​​​