COVID-19 Vaccine FAQ

Below are frequently asked questions about the COVID-19 vaccines. For the most recent updates about the vaccine, including information about distribution phases, visit our COVID-19 Vaccine Information and Update page.

About the COVID-19 Vaccines

Which vaccines will be available?

Two vaccines have now received emergency use authorization from the FDA for their COVID-19 vaccines. On Friday, December 12,  the FDA issued its authorization for individuals age 16 and older for the Pfizer vaccine, and on Friday, December 18, the vaccine produced by Moderna was approved by the FDA as well. Visit the Pfizer-BioNTech COVID-19 Vaccine page on the FDA website for more information about the Pfizer vaccine.

In addition, several other coronavirus vaccines are expected to be approved in the coming months. All vaccines approved for emergency use will have been reviewed for safety and effectiveness.

How do the vaccines work?

All COVID-19 vaccines cause the immune system to respond against the virus that causes COVID-19. The two available vaccines made by Pfizer and Moderna are both mRNA vaccines.

  1. mRNA vaccines give instructions to our cells to make a harmless piece of “spike protein.” The spike protein is found on the surface of the virus that causes COVID-19.
  2. After the spike protein is made, the cell breaks down the instructions (mRNA) and gets rid of them.
  3. The body now recognizes that the spike protein should not be there. It builds immune cells (called antibodies) that will remember how to fight the virus that causes COVID-19 if we are infected in the future.

Important Note: mRNA vaccines do not contain a live virus and do not cause disease in the vaccinated person. The mRNA vaccines do not change the recipient's DNA.

What ingredients are in the Pfizer vaccine?

The Pfizer vaccine contains:

  • Messenger ribonucleic acid (mRNA) – the main, active ingredient that elicits an immune response and the production of antibodies
  • Lipids (including ((4-hydroxybutyl)azanediyl)bis(hexane-6,1-diyl)bis(2-hexyldecanoate), 2 [(polyethylene glycol)-2000]-N,N-ditetradecylacetamide, 1,2-Distearoyl-sn-glycero-3- phosphocholine, and cholesterol) – an outside coating or shell of fat that protects the mRNA from destruction as it is being stored, administered and delivered to cells
  • Potassium chloride; monobasic potassium phosphate; sodium chloride (salt); dibasic sodium phosphate dehydrate – salts that are used to maintain proper levels of acidity (pH)
  • Sucrose – a sugar that stabilizes the suspension

What ingredients are in the Moderna vaccine?

The Moderna COVID-19 vaccine contains:

  • Messenger ribonucleic acid (mRNA) - the main, active ingredient that elicits an immune response and the production of antibodies
  • Lipids (SM-102, polyethylene glycol [PEG] 2000 dimyristoyl glycerol [DMG],cholesterol, and 1,2-distearoyl-sn-glycero-3-phosphocholine [DSPC])- an outside coating or shell of fat that protects the mRNA from destruction as it is being stored, administered and delivered to cells
  • Tromethamine,tromethamine hydrochloride, acetic acid, sodium acetate - used to maintain proper pH
  • Sucrose – a sugar that stabilizes the suspension

How are the Moderna and Pfizer vaccines different?

The Moderna and Pfizer vaccines use the same technology but contain slightly different mRNAs and different ingredients used to protect the mRNA, maintain the pH and stabilize the solution. They are essentially equally effective and have similar side effects.

How effective is the vaccine?

In clinical trials, the Pfizer and Moderna vaccines were shown to be about 95% effective at preventing illness caused by the coronavirus.

How much does the COVID-19 vaccine cost?

There is no out-of-pocket cost to receive the COVID-19 vaccine.

The federal government is providing the vaccine itself at no cost to patients.

There is a vaccine administration fee for supplies, facilities, staffing and other expenses that will be covered in full by your insurance company, Medicaid, Medicare, or the federal government if you do not have insurance.

If you receive a bill in error, please call Patient Financial Experience at 855-855-0863 or 734-615-0863.

Where can I learn more about the COVID-19 vaccines?

For current and accurate information  about the COVID-19 vaccines visit:

Getting the Vaccine

Who will be able to get the vaccine?

Michigan Medicine is administering the COVID-19 vaccine based on guidance from the Michigan Department of Health and Human Services (MDHHS). MDHHS follows Centers for Disease Control (CDC) recommendations based on input from the Advisory Committee on Immunization Practices (ACIP), a CDC advisory committee made up of medical and public health experts who develop recommendations on the use of vaccines in the United States.

The CDC and ACIP have defined populations for different vaccination phases:  

  • Phase 1A: Includes paid and unpaid persons serving in health care settings who have direct or indirect exposure to patients or infectious materials and are unable to work from home, as well as residents of long-term care facilities.  
  • Phase 1B: Includes people age 75 and older, as well as frontline essential workers including first responders, Pre K-12 education, food and agriculture, manufacturing, corrections, postal service, public transit, and grocery store workers.
  • Phase 1C: Includes people age 65 and older as well as those at high risk for severe COVID-19 illness due to underlying medical conditions such as COPD, hypertension, chronic kidney disease, heart disease, diabetes, obesity or other conditions that puts them at high risk of negative COVID-19 outcome. Phase 1C also includes essential workers in transportation and logistics, food service, construction, finance, IT and communication, energy, media, legal, public safety (engineers, water and wastewater).
  • Phase 2:  A mass vaccination campaign for all people age 16 and older.

How can a Michigan Medicine patient schedule an appointment to receive the COVID-19 vaccine?

Michigan Medicine will provide COVID-19 vaccinations to patients who are under the care of a Michigan Medicine primary care provider, as well as patients who have had an in person or virtual appointment with any Michigan Medicine provider in the last 24 months.

As we follow the State of Michigan’s vaccine distribution phases, different groups of patients will become eligible to receive the vaccine in each phase.  See “Who will be able to get the vaccine,” above for a summary of the phases.

Within each phase, patients will receive vaccine invitations in waves to ensure a seamless experience at our vaccine clinics, and to ensure adequate vaccine supply.

Registered MyUofMHealth patient portal users will receive their invitation to schedule a vaccination by email and through a notification in their portal account. They will be able to schedule their appointment directly through the portal.

If you do not have a MyUofMHealth portal account, you may sign up for one on MyUofMHealth.org.

Established patients who are not portal users will receive an invitation to schedule an appointment through a mailed letter.

No action is needed at this time to request an invitation. Established patients will receive an invitation automatically as we move through the vaccine distribution program. Contacting your clinic will not affect your ability to get vaccinated sooner.

Frontline essential workers: To ensure efficient vaccine distribution, a number of different providers are involved in administering vaccines to support critical infrastructure in our communities. To receive the COVID-19 vaccine as quickly as possible, frontline essential workers should contact their employer or health department for additional information about vaccination options available to them.

How can someone who is not a Michigan Medicine patient or employee get the COVID-19 vaccine?

We recommend individuals who are not established Michigan Medicine patients contact their health care provider or their county health department for vaccination options. The distribution of vaccines across the state through different providers is designed to support the most broad, equitable vaccine access as possible.

Frontline essential workers: To ensure efficient vaccine distribution, a number of different providers are involved in administering vaccines to support critical infrastructure in our communities. To receive the COVID-19 vaccine as quickly as possible, frontline essential workers should contact their employer or health department for additional information about vaccination options available to them.

Will priority for vaccines be given to those in facilities with more vulnerable populations?

Yes, the goal is to administer the initially limited supply of vaccines to those most at risk, following CDC guidelines for a phased rollout.

Can I get the vaccine if I’ve had COVID-19 or think I may have had COVID-19 in the past?

According to CDC, vaccination should be offered regardless of history of prior symptomatic or asymptomatic SARS-CoV-2 infection. Data from phase 2/3 clinical trials suggest vaccination is safe and likely efficacious in these people.

Current evidence suggests that people who have had COVID-19 may be protected for up to 90 days after their initial infection, so they may decide to wait until after this period, if desired.

Can I get the vaccine if I've participated in a COVID-19 clinical research trial?

Go to your study team coordinator with any questions you have about your eligibility to receive the COVID-19 vaccine once it becomes available.

Are there any restrictions about who can receive the COVID-19 vaccine?

Yes, there are several things to keep in mind when the time comes to schedule your appointment for a COVID-19 vaccine. You cannot receive the vaccine if any of the following are true: 

  • You have received another vaccine in the last 14 days (including vaccines such as Hepatitis B, Shingrix, Tetanus, seasonal flu, etc.)  
  • You have been diagnosed with COVID-19 in the last 10 days 
  • You have received an infusion of COVID-19 monoclonal antibodies in the past 90 days

Can the COVID-19 vaccine be administered with other vaccines?

Given the lack of data on the safety and efficacy of mRNA COVID-19 vaccines administered simultaneously with other vaccines, the vaccine series should be administered alone, with a minimum interval of 14 days before or after administration with any other vaccine. If mRNA COVID-19 vaccines are inadvertently administered within 14 days of another vaccine, doses do not need to be repeated for either vaccine.

How many shots am I going to need?

The Pfizer vaccine requires 2 doses, 21 days apart. The Moderna vaccine requires 2 doses, 28 days apart. It takes time for your body to build protection after any vaccination. The two COVID-19 vaccines may not protect you until 1-2 weeks after your second shot.

I already had COVID-19 and recovered. Do I still need to get vaccinated?

There is not enough information currently available to say if or for how long after infection someone is protected from getting COVID-19 again. This is called natural immunity. Early evidence suggests that people who recovered from COVID-19 are not likely to get the infection again in the 90 days after the initial infection. If you tested positive and recovered from COVID-19 you may decide to wait until near the end of this period to get vaccinated.

Safety, Side Effects and Other Concerns

How did a vaccine get developed and approved so quickly? Was the process rushed?

Producing a vaccine against COVID-19 has been the top priority of scientists and governments around the world to help bring an end to the pandemic. With the coordinated and enormous investment of resources, development of these vaccines has been accelerated, all while maintaining standards for safety and efficacy.

Rather than eliminating steps from traditional vaccine development timelines, steps are proceeding simultaneously, such as scaling up manufacturing while safety and efficacy data are collected.

How do we know if the vaccines are safe?

COVID-19 vaccines were tested in large clinical trials that included tens of thousands of people. This is done to make sure they meet safety standards and see how the vaccines offer protection to people of different ages, races, and ethnicities, as well as those with different medical conditions. No significant safety concerns were identified in the clinical trials. At least 8 weeks of safety data were gathered in the trials. It is unusual for side effects to appear more than 8 weeks after vaccination.

Important note: The development of these vaccines has been accelerated while maintaining all safety standards. Rather than eliminating steps from traditional vaccine development timelines, steps were happening at the same time, such as scaling up manufacturing while safety and efficacy data are collected.

Is the vaccine safe for pregnant women and women trying to conceive?

With the information currently available, we at Michigan Medicine believe the benefit of receiving the COVID-19 vaccine is greater than the risks of getting COVID-19 for women who are pregnant, breastfeeding or trying to conceive. There is no specific safety information about the COVID-19 vaccine in pregnancy because pregnant women were not included in the early studies. However, most scientists, doctors and national organizations support pregnant women receiving the vaccine because the risks of COVID-19 in pregnancy can be severe.

Additionally, the Academy of Breastfeeding Medicine does not recommend stopping breastfeeding for people who get the COVID-19 vaccine and the American College of Obstetrics and Gynecology advises that it is not necessary to delay pregnancy after completing both doses of the vaccine. To help make your decision about receiving the vaccine, be sure to speak with your health care provider.

Is the vaccine safe for people with conditions or medications that can weaken the immune system?

The early clinical trials did not test the vaccines in these populations but based on the current data, the benefit of receiving the COVID-19 vaccine is greater than the risks of getting COVID-19. Talk to your health care provider about the potential risks and benefits of the vaccine in your specific situation. 

What are the side effects of the vaccine?

In the vaccine clinical trials, most people did not have serious problems after being vaccinated. The symptoms usually went away on their own within a week. Some people reported getting a headache or fever when getting a vaccine. These side effects are a sign that your immune system is doing exactly what it is supposed to do. It is working to build up protection against disease.

More people experienced these side effects after getting the second dose than the first one.

If you get the vaccine and become immune, then are exposed to it, can you pass the virus on to others from your exposure?

Based on our experience with other vaccines and early data from the COVID-19 vaccines, it is likely that people who are vaccinated will have enough immunity where they will not pass the virus to others if exposed, but this is not 100 percent certain.

I’m not sure about the COVID-19 vaccine. Where can I find information to help me decide?

Maybe you’ve heard a claim about the COVID vaccines on social media or from a friend or relative that is making you wary about getting vaccinated when it’s your turn.  

We collected some of the most widespread rumors, claims, myths and worries about the COVID-19 vaccines, and checked them out with help from Michigan Medicine experts. Read the questions and answers on our Michigan Health blog post: “Not Sure About the COVID-19 Vaccine? Get the Facts, Then Decide”.

After Vaccination

How long do the vaccines protect against infection?

Health care professionals and researchers are still learning about COVID-19 and new information is discovered nearly every day that is helpful in the fight against this disease. Because COVID-19 is still a relatively new virus, it is difficult to know exactly how the virus affects the body long-term and how long immunity from natural infection lasts.

Therefore, it is also difficult to predict how long a vaccine will provide protection against the virus. As the vaccines are administered and new information is gathered, additional data about how long it will protect against the virus will be made available. 

Will the vaccine be given annually or is it only for this year?

This is not known at this time. Scientists are continuing to collect data about long-term immunity to SARS-CoV2.

Do I need to wear a mask and avoid close contact with others if I have received 2 doses of the vaccine?

Yes. While experts learn more about the protection that COVID-19 vaccines provide under real-life conditions, it will be important for everyone to continue using all the tools available to us to help stop this pandemic, like covering your mouth and nose with a mask, washing hands often, and staying at least 6 feet away from others. Experts need to understand more about the protection that COVID-19 vaccines provide before deciding to change the recommendations.