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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 350 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, 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.

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.

• As of Aug. 2, 2021, over 99.99% of fully vaccinated people have not had a breakthrough case of COVID-19 resulting in hospitalization or death.

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?

• CDC recommends that people who are moderately to severely immunocompromised receive an additional dose of an mRNA COVID-19 Vaccine (Pfizer-BioNTech or Moderna) at least 28 days after the completion of the initial mRNA COVID-19 vaccine series.

• A third dose of the Comirnaty (Pfizer-BioNTech) COVID-19 vaccine six months after the primary series of Comirnaty (Pfizer-BioNTech) is now available for certain groups. The Centers for Disease Control and Prevention (CDC) recommends:
   • People 65 years and older and residents in long-term care settings should receive a booster shot;
   • People aged 50–64 years with underlying medical conditions should receive a booster shot;
   • People aged 18–49 years with underlying medical conditions may receive a booster shot based on their individual benefits and risks; and
   • People aged 18-64 years who are at increased risk for COVID-19 exposure and transmission because of where they work or live may receive a booster shot based on their individual benefits and risks.

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. The vaccine also continues to be available under emergency use authorization (EUA), including for individuals 12 through 15 years of age and for the administration of a third dose in certain immunocompromised individuals.

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 Comirnaty (Pfizer) vaccine is given in 2 doses, 3 weeks apart. 3rd dose recommended 28 days later for immunocompromised.

• The Moderna vaccine is given in 2 doses, 4 weeks apart. 3rd dose recommended 28 days later for immunocompromised.

• The Janssen (Johnson & Johnson) COVID-19 vaccine is a single dose vaccine.

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

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

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  ​​​