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COVID-19 vaccine frequently asked questions

Below are commonly asked questions and answers regarding COVID-19 vaccination. This page has useful information before you are able to get vaccinated, during your vaccine appointment, and after you receive the vaccine, as well as information about vaccine safety.

Table of Contents

Before getting vaccinated

Will I have to pay for the vaccine?

No. The vaccine is being provided free of charge to all individuals by the federal government.  If you have insurance, it will be billed at no cost to you. However, you do not need to be insured to receive the vaccine. You will never be asked for a credit card number to make an appointment.  

May undocumented immigrants receive the vaccine for free?

Yes.  The vaccine itself is free for all individuals in Massachusetts.  Health insurance (including Medicare and Medicaid) will cover the cost of administering the vaccine.  For patients without health insurance, health care providers may request reimbursement from the federal government for the cost of administering vaccine to undocumented immigrants.

Can I still get the vaccine if I don't have an ID card?

Yes. You can get a vaccine even if you do not have insurance, a driver’s license or a Social Security number. For more information, visit How to prepare for your COVID-19 vaccine appointment.

Will getting the vaccine negatively impact a person’s immigration status?

No.  The federal government has confirmed that it will not consider COVID-19 treatment (including a vaccine) as part of a determination of whether someone is a “public charge” or as it relates to the public benefit condition for certain individuals seeking an extension of stay or change of status, even if the vaccine is paid for by Medicaid or other federal funds.

Is a patient’s vaccination record protected from disclosure?

The Department of Public Health will maintain an electronic record of each patient in Massachusetts who receives the COVID-19 vaccine.  The vaccine database is kept confidential like a patient’s medical record with his or her doctor.

Is the COVID-19 vaccine mandatory?

The Department of Public Health is not mandating the COVID-19 vaccine. It is a voluntary program. The COVID-19 vaccine has been shown to be highly effective at preventing illness and it is an important tool in the fight against the pandemic.​

Will I need to be tested for COVID-19 before getting the vaccine?

No, a COVID-19 test is not needed before getting the vaccine. 

Should someone who is COVID-19-positive receive the vaccine?

No. People who are known to have COVID-19 should wait to be vaccinated until their isolation period has ended, usually 10 days after symptoms started or, if they didn’t have symptoms, 10 days after their test was positive. 

Should people who have had COVID-19 be vaccinated?

Yes, people who have previously had COVID-19 should be vaccinated.

Can people who live in another state or country part time (e.g. students, retirees, people with dual citizenship get the COVID-19 vaccine in Massachusetts? (Updated 5/13/21)

Yes. The Massachusetts COVID-19 Vaccination program is intended for individuals who live, work or study in the Commonwealth.  You may also get your second dose in Massachusetts if you received the first dose in another state. Please be sure to keep the vaccination card you were given at the time of the first dose. 

What are the benefits of getting a COVID-19 vaccine? 

COVID-19 vaccination will help keep you from getting sick from COVID-19.  All COVID-19 vaccines available in the U.S. have been shown to be very effective. Experts continue to conduct more studies about whether the vaccines also keep people from spreading COVID-19. Wearing masks and social distancing help lower your chance of getting the virus or spreading it to others, but these measures are not enough. The combination of getting vaccinated and following CDC’s recommendations to protect yourself and others will offer the best protection from COVID-19.

How will vaccines work against COVID-19 variants, like the one that appeared in the United Kingdom?

It is normal for viruses to change as they spread, and for new variants to appear. Scientists are working to learn more about whether the vaccines we already have will protect people against COVID-19 variants. The Janssen (Johnson & Johnson) vaccine was studied in multiple countries, including South Africa and Brazil, both places where COVID-19 variants have appeared. So far, studies suggest that currently authorized vaccines provide protection from the variants.  

Does the Johnson & Johnson COVID-19 vaccine provide as much protection as the Pfizer and Moderna vaccines?

All three approved COVID-19 vaccines are safe and highly effective against serious illness, hospitalization, and death. The Janssen (Johnson & Johnson) vaccine provided 93% protection against hospitalization from COVID-19. It was also shown to be effective against the new COVID-19 variants, with research conducted in countries with these more infectious variants including South Africa and Brazil. An added benefit is that the Janssen (Johnson & Johnson) vaccine requires only a single shot – so if you are offered it, you are “one and done” and don’t need to make a second appointment.  

What is an Emergency Use Authorization?

Three vaccines – Pfizer,Moderna, and Janssen (Johnson & Johnson) – have received Emergency Use Authorization (EUA) from the federal Food and Drug Administration. Learn more about what this means – and other information about the vaccines – in their EUA fact sheets for recipients and caregivers. These factsheets can be found at:

During your appointment

What can I expect at my appointment to get vaccinated for COVID-19?

Please visit What to Expect at Your Appointment to Get Vaccinated for COVID-19 | CDC for tips on what to expect when you get vaccinated, what information your provider will give you, and resources you can use to monitor your health after you are vaccinated.

Do I need to wear a mask when I receive a COVID-19 vaccine? 

Yes, you must wear a mask that covers your nose and mouth during your appointment.

Can I choose which vaccine I receive?

No. Recipients will receive the vaccine offered to them when they attend a vaccination clinic. All of the vaccines are highly effective and safe. The best vaccine is the one that is available to you.  People are urged to take whatever shot they can, as soon as it’s available.

How long do I have to wait between the first and second dose of the COVID-19 vaccine for Pfizer and Moderna?

Your second shot is recommended at 21 days for Pfizer and 28 days for Moderna, but any time up to 6 weeks (42 days) after the first dose is in line with CDC guidance. You should not get the second dose earlier than 21 days for Pfizer or 28 days for Moderna. The Janssen (Johnson & Johnson) vaccine is only one dose.

How effective is one dose of a Pfizer or Moderna COVID-19 vaccine compared to two doses?

The Pfizer and Moderna COVID-19 vaccines were not studied for use as a single dose. People should get both doses of the vaccine to be fully vaccinated.

Will I be monitored after being vaccinated?

People who have a history of anaphylaxis (severe allergic reaction) from any cause ​are observed for 30 minutes. All others are monitored for 15 minutes.

What medical personnel and equipment are on site at the mass vaccination clinics?

Each mass vaccination site has qualified vaccine administrators (the people who give the vaccine) who can review a person’s eligibility to receive a vaccine and answer a patient’s questions before giving the shot. Each site has qualified medical professionals on site providing vaccines, overseeing the vaccine process, and observing patients for 15-30 minutes afterwards.

The mass vaccination sites are prepared to handle medical emergencies and adverse reactions with their medical staff on site and often have ambulances on site to assist as needed. If you are concerned about having an adverse reaction to the vaccine, you should first discuss your concerns with your health care provider before arriving on site. Patients are required to share their vaccine and health history with the person who is vaccinating them and should discuss any concerns or questions with them before getting the vaccine.

Will I receive anything to show proof of vaccination?

You should receive a vaccination card or printout that tells you what COVID-19 vaccine you received, the date you received it, and where you received it. Please be sure to keep this card for your second dose. You may take a photo of your card as a backup digital copy.

You should receive a paper or electronic version of a fact sheet that tells you more about the specific COVID-19 vaccine you are being offered. Each authorized COVID-19 vaccine has its own fact sheet that contains information to help you understand the risks and benefits of receiving that specific vaccine. The factsheets can be found at Pfizer-BioNTech COVID-19 Vaccine EUA Fact Sheet for Recipients and Caregivers (fda.gov), Moderna COVID-19 Vaccine EUA Fact Sheet for Recipients and Caregivers (fda.gov), and Janssen COVID-19 Vaccine EUA Fact Sheet for Recipients and Caregivers (fda.gov)

What should I do if I lose my COVID-19 Vaccination Record Card?

You have a few options:

  1. Contact your healthcare provider or the location where you were vaccinated. They can print out another copy of your record.
  2. Your record will also be in v-safe, if you enrolled in the program.  
  3. You can fill out an Immunization Record Request Form that goes directly to the state Department of Public Health. If you use this form, you will get a complete history of all vaccines you’ve gotten, not just the COVID-19 vaccine, and it can take up to 6 weeks to get your records.

    After getting vaccinated

    What should I do if I experience symptoms after receiving a COVID-19 vaccine?

    Some people have side effects after being vaccinated (such as tiredness, headache, and pain at the injection site), which are normal signs that your body is building protection. These side effects may affect your ability to do daily activities, but they should go away in a few days. If you develop respiratory symptoms like runny nose, cough, or loss of sense of smell or taste, these are not side effects of the vaccine and you should consider getting tested for COVID-19 or talk to your healthcare provider. It is possible to get COVID-19 even after you get the vaccine. Stay home if you are sick and avoid close contact with others.  You may wish to check with your employer about how this will impact your work.

    If you have any significant pain or discomfort, talk to your healthcare provider, who may recommend over-the-counter medicine, such as ibuprofen or acetaminophen. To reduce pain and discomfort where you got the shot apply a clean, cool, wet washcloth over the area, and use or exercise your arm.  To reduce discomfort from fever, drink plenty of fluids and dress lightly. In most cases, discomfort from fever or pain is normal, but contact your healthcare provider if:

    • the redness or tenderness where you got the shot increases after 24 hours
    • your side effects are worrying you or do not seem to be going away after a few days

    How do I report if I have any side effects after getting the COVID-19 vaccine?

    V-safe is a smartphone-based tool that uses text messaging and web surveys to provide personalized health check-ins after you receive a COVID-19 vaccination. Through v-safe, you can quickly tell CDC if you have any side effects after getting the COVID-19 vaccine. Depending on your answers, someone from CDC may call to check on you and get more information. And v-safe will remind you to get your second COVID-19 vaccine dose if you need one. To sign up for v-safe, please visit V-safe After Vaccination Health Checker | CDC.

    If you have any concerns, you can also call your healthcare provider.  You or your provider can report any side effects to the Vaccine Adverse Event Reporting System (VAERS), which is a national system run by the federal government.

    How long after getting the COVID-19 vaccine does it take to be effective?

    It usually takes a few weeks for the body to build immunity after vaccination. That means it's possible a person could be infected with the virus that causes COVID-19 just before or just after vaccination and get sick. This is because the vaccine has not had enough time to provide protection. You are considered fully vaccinated if you have received two doses of either the Moderna or Pfizer COVID-19 vaccines or a single dose of the Janssen (Johnson & Johnson) vaccine more than 14 days ago. 

    How long does protection from the COVID-19 vaccines last? 

    We do not have data yet to say for how long the COVID-19 vaccines will provide protection. Experts are working to learn more about both the protection someone gets from having an infection (also called natural immunity) and protection someone gets from the vaccine.

    What guidance do I need to follow after I am fully vaccinated?

    Some prevention measures will continue to be necessary for all people, even people who have been fully vaccinated. For more information, please visit Guidance for people who are fully vaccinated against COVID-19 | Mass.gov.

    Vaccine safety

    Is the Johnson & Johnson vaccine safe? (New 5/13/21)

    All COVID-19 vaccines are safe and highly effective against serious illness, hospitalization, and death. There is a risk of a rare but serious condition involving blood clots and low platelets in people after receiving the J&J COVID-19 Vaccine. This risk is very low, and the benefits outweigh this risk. Review this factsheet for more information.

    How do we know if the vaccine is safe?

    It’s important to know that vaccines go through more testing than any other pharmaceuticals.  First, small groups of people receive the trial vaccine. Next, vaccine is given to people with certain characteristics (e.g., age, race, and physical health). Then, vaccine is given to tens of thousands of people and tested for effectiveness and safety.

    After that, the CDC’s Advisory Committee on Immunization Practices (ACIP) looks at the data to see whether the vaccine works and is safe.  They give advice to the United States Food and Drug Administration (FDA). The FDA looks at the data and the advice from the ACIP and decides whether to approve the vaccine. The vaccine is only approved after all of these steps are done, and the experts are sure that it works and is safe.

    Visit Ensuring the Safety of COVID-19 Vaccines in the United States | CDC for more information.

    How is it safe if it happened so fast?

    The timeline to develop a COVID-19 vaccine was sped up but never cut corners on safety. Here is how:

    1. We already had helpful information: The COVID-19 virus is a part of a coronavirus family that has been studied for a long time. Experts learned important information from other coronavirus outbreaks that helped them to develop the COVID-19 vaccine, so we weren’t starting from scratch.
    2. Governments funded vaccine research: The United States and other governments invested a lot of money to support vaccine companies with their work. Working together with other countries also helped researchers move quickly.
    3. A lot of people participated in clinical trials: Many people wanted to help by being in the vaccine studies. Companies didn’t need to spend time finding volunteers.
    4. Manufacturing happened at the same time as safety studies: Vaccine companies were able to make and store doses of vaccine at the same time as studies (called clinical trials) were happening to show that the vaccines were safe and effective. This meant vaccines were ready to be distributed once they were approved.

    How is it safe if we don’t know the long-term side effects?

    The Pfizer and Moderna COVID-19 vaccines are what experts call messenger RNA vaccines, or mRNA vaccines for short. The Janssen (Johnson & Johnson) vaccine is called a viral vector vaccine. Both types of vaccines have been studied in animal and human trials for years. On the other hand, COVID-19 has only been around for about a year and the long-term side effects of COVID-19 infection are mostly unknown and may be serious. Therefore, getting vaccinated is the best choice for long-term health and safety.  

    Experts will continue to track COVID-19 vaccine side effects. People in clinical trials will be tracked for 2 years. Other people who get the vaccine can use a tool called v-safe on their smartphones to quickly tell the CDC if you have any side effects after getting the COVID-19 vaccine. V-safe users can share information for up to one year after their vaccine. Learn more at cdc.gov/vsafe.

    Do the COVID-19 vaccines have any side effects?

    Some people may have side effects after being vaccinated, which are normal signs that your body is building protection. These side effects may affect your ability to do daily activities, but they should go away in a few days. The most common side effects are minor and include tiredness, headache, pain at the injection site, muscle and/or joint pain, chills, nausea and/or vomiting, and fever.

    Can a COVID-19 vaccine make me sick with COVID-19?

    No. The Pfizer, Moderna, and Janssen (Johnson & Johnson) vaccines do not contain the live virus that causes COVID-19. This means that a COVID-19 vaccine cannot make you sick with COVID-19. (source: Facts about COVID-19 Vaccines (cdc.gov). Therefore, if you test positive for COVID-19, even if you have gotten the vaccine, you would need to isolate.

    Should someone with a history of allergies get the COVID-19 vaccine?

    You should not get the Pfizer, Moderna or Janssen (Johnson & Johnson) COVID-19 vaccines if you have a history of severe allergic reaction (also called anaphylaxis) to any ingredient in the vaccine. If you have a history of a severe allergic reaction  to something else that’s not in the vaccine, discuss with your health care provider before receiving the vaccine.

    Although there is a small chance that the COVID-19 vaccines could cause a severe allergic reaction, this would usually happen within a few minutes to one hour after getting the vaccine. Everyone, even if they don’t have allergies, is monitored for at least 15 minutes after getting a COVID-19 vaccine.

    Should I go to a mass vaccination clinic if I have a history of severe allergic reactions?

    All vaccination sites can respond to rare severe allergic reactions and anaphylaxis that can occur following vaccination. If you have a severe or immediate allergic reaction to the first dose you should not receive a second dose.  People who have had a severe allergic reaction to other vaccines or injected medications should let staff at the vaccination clinic know before being vaccinated. You may also wish to discuss COVID-19 vaccination with your healthcare provider before the visit.

    What are the ingredients in the vaccine?

    The vaccines do not contain eggs, gelatin, preservatives, or latex. COVID-19 vaccine fact sheets for recipients and caregivers list the ingredients of each vaccine. They can be found at:

    I would like to have a baby one day. Is it safe for me to get a COVID-19 vaccine?

    Yes. People who want to get pregnant in the future may receive the COVID-19 vaccine. COVID-19 vaccines are being studied carefully now and will continue to be studied for many years, similar to other vaccines. Based on what we know right now, experts believe that COVID-19 vaccines are safe for someone who is trying to become pregnant in the short or long term.

    Here’s why:

    • The COVID-19 vaccine, like other vaccines, works by teaching our bodies to develop antibodies that fight against the virus that causes COVID-19, to prevent future illness.  
    • There is no evidence right now that antibodies formed from COVID-19 vaccination will cause any problems with pregnancy, including the development of the placenta.
    • In fact, there is no evidence that fertility problems are a side effect of ANY vaccine.

    People who are trying to become pregnant now or who plan to try in the future may receive the COVID-19 vaccine when it becomes available to them. (source: Facts about COVID-19 Vaccines (cdc.gov))

    Can someone who is pregnant or breastfeeding get a COVID-19 vaccine? (Updated 5/13/21)

    Yes. The American College of Obstetricians and Gynecologists recommends that COVID-19 vaccines be offered to pregnant and breastfeeding individuals.. COVID-19 infection during pregnancy can increase the risk of severe illness and might result in an increased risk of outcomes like preterm birth. Currently there are limited data on the safety of COVID-19 vaccines in people who are pregnant or breastfeeding. However, early data on COVID-19 vaccination during pregnancy did not identify any safety concerns for pregnant people who were vaccinated or for their babies.

    Getting vaccinated is a personal choice for people who are pregnant or breastfeeding. If you have questions, a discussion with your healthcare provider might help but is not required for vaccination. For more information, visit Information about COVID-19 Vaccines for People who Are Pregnant or Breastfeeding | CDC.

    Are the COVID-19 vaccines safe for children? (Updated 5/13/21)

    At this time, the Pfizer vaccine is authorized for people ages 12 and older, and the Moderna and Janssen (Johnson & Johnson) vaccines are authorized for people ages 18 and older. Younger children and adolescents should not receive COVID-19 vaccination at this time.

    Who were the vaccines tested on? (Updated 5/13/21)

    The safety of the Pfizer COVID-19 vaccine was evaluated in people 16 years of age and older in two clinical studies conducted in the United States, Europe, Turkey, South Africa, and South America. Overall, 50.6% of participants were male and 49.4% were female, 83.1% were White, 9.1% were Black or African American, 28.0% were Hispanic or Latino, 4.3% were Asian, and 0.5% were American Indian or Alaska Native. The safety of the Pfizer vaccine in younger adolescents was studied in 2,260 adolescents ages 12-15 in the U.S.  

    The safety of the Moderna COVID-19 vaccine was evaluated in people 18 years of age and older in the United States. Overall, 52.7% of participants were male, 47.3% were female, 79.2% were White, 10.2% were Black or African American, 20.5% were Hispanic or Latino, 4.6% were Asian, 0.8% were American Indian or Alaska Native, 0.2% were Native Hawaiian or Pacific Islander, 2.1% were Other, and 2.1% were Multiracial.

    The safety of the Janssen (Johnson & Johnson) vaccine was evaluated in people 18 years of age and older in the U.S., Brazil, South Africa, Colombia, Argentina, Peru, Chile, and Mexico. Overall, 45% of participants were female, 55% were male, 58.7% were White, 19.4% were Black or African American, 45.3% were Hispanic or Latino, 3.3% were Asian, 9.5% were American Indian/Alaska Native 0.2% were Native Hawaiian or other Pacific Islander, 5.6% were from multiple racial groups and 1.4% were unknown races.

    Will a COVID-19 vaccine change my DNA?

    No. The COVID-19 vaccines do not change or interact with your DNA in any way.

    Vaccines teach our immune system how to fight against a specific virus. They work with the body’s natural defenses to safely develop immunity to disease.  In order to do its job, the COVID-19 vaccine doesn’t need to go inside the nucleus of the cell, which is where our DNA is kept. This means the vaccine never interacts with our DNA in any way and has no way to change it.

    At the end of the process, our bodies have learned how to protect against future infection. That immune response and making antibodies is what protects us from getting infected if the real virus enters our bodies. (source: Facts about COVID-19 Vaccines (cdc.gov)

    More information

    Visit these frequently updated Centers for Disease Control and Prevention (CDC) web pages on COVID-19 vaccination:

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