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If you already have COVID-19, consider joining an ACTIV clinical trial for COVID-19 treatments. To learn more:

Visit the clinical trials page

The COVID-19 vaccine helps your body protect itself against the virus that causes COVID-19 infection. There are different types of the COVID-19 vaccine available to people in different age groups. The vaccine “teaches” your body’s immune system how to make antibodies specifically against the virus that causes COVID-19. These antibodies give your body a better chance of fighting the virus if you come into contact with someone who does have COVID-19. Your risk for serious outcomes from COVID-19 are much less when your body has this protection from the vaccine. It is given to you as a series of one or two shots, depending on the type of COVID-19 vaccine you get.

Experts continue to study changes in both the virus and vaccines to find the best protection for everyone. Three vaccines are now available:

  • The Pfizer-BioNTech COVID-19 vaccine uses part of the virus’ special genetic code (called messenger RNA or mRNA) to “teach” your body’s immune system how to make antibodies that defend your body against the virus that causes COVID-19. This vaccine is for people ages 5 and older. It requires two injections given at least 21 days apart. The second dose can be given up to 6 weeks after the first dose, if needed.
  • The Moderna COVID-19 vaccine uses mRNA in the same way the Pfizer-BioNTech COVID-19 vaccine does. The Moderna vaccine is given to people ages 18 and older. It requires two injections given at least 28 days apart. The second dose can be given up to 6 weeks after the first dose, if needed.
  • The Johnson & Johnson (J&J)/Janssen COVID-19 vaccine is a “vector” vaccine. Vector vaccines train your body to make antibodies in almost the same way the Moderna and Pfizer-BioNTech mRNA vaccines do. However, this type of vaccine uses a different type of genetic information (DNA) to “teach” your body how to defend itself against the virus. It is given to people ages 18 and older and requires one shot.

A COVID-19 vaccine may help:

  • Prevent you from getting COVID-19 or, if you get it, from becoming seriously ill or dying from COVID-19.
  • Prevent you from spreading the virus that causes COVID-19 to other people, including loved ones or those who are at risk for serious illness from COVID-19.
  • Help your community reach the goal of “herd” immunity. This means most people in a community have protection against the virus. Herd immunity helps prevent the spread of COVID-19.
  • Prevent more variants or mutant strains of COVID-19 from developing by curbing the spread of the disease faster.
  • Help everyone #CombatCOVID.

Once you are fully vaccinated, you may be able to get back to doing some things you stopped doing because of the pandemic. For example, you can gather indoors, without masks, and with other people who are fully vaccinated.

The COVID-19 vaccines are considered safe and effective. All three vaccines have been closely studied by researchers for safety, effectiveness, and manufacturing quality. In fact, vaccines, treatments, and medical devices all go through careful and strict testing in a lab before being tested in humans. Vaccines are only tested in people if they are deemed safe, starting with about 20 to 100 volunteers. Testing then expands to thousands of people before data on the safety and effectiveness of the vaccine is reviewed by the U.S. Food and Drug Administration (FDA) for possible Emergency Use Authorization (EUA) approval.

Since FDA EUA approval of all three vaccines in December 2020, millions of people in the United States have received the shots. The Centers for Disease Control and Prevention (CDC) and the FDA continue to monitor all vaccines for safety, but long-term side effects are unlikely. Serious allergic reactions to the vaccine are rare. If a reaction like this happens, it will likely happen while you are at the location where you get the vaccine. This is why you are asked to wait a few minutes after getting your vaccine before you leave the vaccine clinic/location. If this type of reaction happens, vaccine providers can quickly and effectively treat it.

None of the vaccines will make you sick with the COVID-19 virus; they do not contain the live virus. None of the vaccines affect or become part of your genetic DNA.

As of November 2021, all people ages 5 years and older are eligible for COVID-19 vaccines in the United States, including all 50 states and Washington, D.C. You do not need to be a U.S. citizen to get the vaccine and your U.S. citizenship status is not asked or reported by vaccine providers. The United States is committed to providing the COVID-19 vaccine to anyone at no cost. To find out more information about vaccine eligibility, visit https://www.cdc.gov/coronavirus/2019-ncov/vaccines/different-vaccines.html.

  • ...I am at high risk for COVID-19 and I have preexisting medical condition(s)? It’s important for adults of any age who have certain underlying medical conditions to get the COVID-19 vaccine because they are at increased risk of getting very sick from COVID-19. You should tell your vaccine provider about any preexisting medical conditions and allergies you may have.

People at high risk for severe (serious) COVID-19 include:

  • Older adults: Adults ages 65+ are at highest risk, with adults ages 85+ at the greatest risk. More than 80 percent of COVID-19 deaths have occurred in people over age 65.
  • People of any age, race, ethnicity, and sex with certain underlying medical conditions such as:
    • Overweight (defined as a body mass index [BMI] of 25 or greater), obesity (BMI of 30–39), or severe obesity (BMI of 40 or greater)
    • Current or former cigarette smoker
    • Pregnancy
    • Diabetes type I or II
    • Heart conditions such as heart failure, coronary artery disease, cardiomyopathies, and possibly high blood pressure (hypertension)
    • Chronic kidney disease
    • Chronic lung diseases, including chronic obstructive pulmonary disease (COPD), asthma (moderate to severe), interstitial lung disease, cystic fibrosis, and pulmonary hypertension
    • Dementia or other neurological conditions such as Alzheimer’s
    • Cancer
    • Down syndrome
    • HIV/AIDS
    • Weakened or immunocompromised immune system caused by conditions and/or treatments
    • Chronic liver disease, such as alcohol-related liver disease, nonalcoholic fatty liver disease, and especially cirrhosis, or scarring of the liver
    • Hemoglobin blood disorders such as sickle cell disease or thalassemia
    • Received a solid organ transplant or blood stem cell transplant (includes bone marrow transplants)
    • Cerebrovascular disease, such as having a stroke
    • Substance use disorder such as alcohol, opioid, or cocaine use disorder

People with underlying medical conditions can get a COVID-19 vaccine as long as they have not had a serious reaction to a COVID-19 vaccine or to any of the individual ingredients in the vaccine.

If you test positive for COVID-19, you may also qualify for an ACTIV clinical trial for COVID-19 treatment or monoclonal antibody treatment. To learn how you can participate, please visit the Clinical Trials page or call 877-414-8106 to speak with an information specialist.

  • ...I’ve already had COVID-19?
    Yes, you should get the vaccine even if you have already had COVID-19. Even if you have already recovered from COVID-19, it’s possible that you could catch COVID-19 again. People who become infected with COVID-19 respond to the virus differently. Therefore, if you become infected with COVID-19, your body may not have built enough of an immune response to protect against future infection. The vaccine will help ensure that your body makes enough antibodies against the COVID-19 virus and helps prevent you from being infected again in the future. The COVID-19 vaccine gives your body a better chance to build the immunity that it needs to fight the virus.
  • ...I have COVID-19 now?
    If you have tested positive for COVID-19, the CDC recommends that you isolate yourself (be alone/stay away from other people) and use precautions (social distancing, wearing a face mask, washing your hands often, etc.) for at least 10 days after your COVID-19 symptoms start or at least 10 days after you test positive for COVID-19—whichever happens first. Before you get the COVID-19 vaccine, you should wait until you do not have any COVID-19 symptoms, have isolated yourself for 10 days, and have not had a fever for 24 hours. After you complete 10 days of isolation and have not had a fever for 24 hours, research has shown that it is safe for people who have had COVID-19 to get the vaccine.

If you already have COVID-19, you can also consider joining an ACTIV clinical trial for COVID-19 treatments. Visit the Clinical Trials page to learn more.

  • ...I am pregnant?
    • People who are pregnant have a higher risk of having worse COVID-19 symptoms than people who are not pregnant. If you are pregnant, breastfeeding, trying to get pregnant now, or might become pregnant in the future, COVID-19 vaccination is recommended. Vaccine monitoring systems for pregnancy are in place to monitor vaccine safety, and so far, they have not identified any specific safety concerns for pregnant people.
    • There is no evidence that fertility problems are a side effect of any vaccine, including COVID-19 vaccines.
    • If you have questions about getting vaccinated while you’re pregnant, a conversation with your healthcare professional can help.
  • ...I have received monoclonal antibody (mAb) treatment?
    • If you have recently received mAb treatment or convalescent plasma to treat COVID-19 the CDC recommends that you wait 90 days after that treatment before you get vaccinated.
    • This also applies if you got sick with COVID-19 and received these treatments while you were waiting for your second dose of the vaccine. You should wait 90 days after you get mAb treatment or convalescent plasma before you get your second dose of vaccine. If you do get a COVID-19 vaccine dose within 90 days after getting antibody therapy, the vaccine dose does not need to be repeated. Researchers are still studying the safety and effectiveness of COVID-19 vaccines for people who have received mAbs or convalescent plasma as part of COVID-19 treatment.

An additional dose is given to people who are immunocompromised and may not have responded to their first series of the vaccine due to an immune suppressing medication or immunodeficiency. It is recommended for people with moderately to seriously compromised immune systems.

A booster dose can be given to people who are fully vaccinated within the recommended time after they have gotten their first COVID-19 vaccine series. It is intended to “boost” the immune response that may have weakened over time. The timing after the first series depends on the type of vaccine you are getting.

Eligibility for additional and booster doses are listed below.

To find out if you are eligible for an additional or booster dose of the COVID-19 vaccine, visit https://www.cdc.gov/coronavirus/2019-ncov/vaccines/different-vaccines.html.

You can receive your COVID-19 vaccine by scheduling an appointment online or by phone, or (in some places) by going to a drive-thru site—at no cost. First, find a COVID-19 vaccine provider location near you by visiting https://www.vaccines.gov.

You may be able to receive the vaccine at a doctor's office, hospital, urgent care center, community health center, state or local health department, mobile clinic, convention center, or cities' public health clinics, sports stadiums, or a retail pharmacy.

You can check your state/territory and local health departments' website for vaccine events and locations. To find your state's/territory’s health department website, visit https://www.cdc.gov/publichealthgateway/healthdirectories/healthdepartments.html.

Clinical trials help us better understand diseases and find new ways to prevent, diagnose, and treat illnesses such as COVID-19. Finding safe and effective vaccines and other preventions that work for everyone is only possible when volunteers of all genders, races, and ethnicities participate in joining clinical trials. To find out if there any clinical trials in your area, visit https://coronaviruspreventionnetwork.org

Yes, it is safe to get the COVID-19 vaccine with other recommended vaccinations and there is no recommended time limits between getting the COVID-19 vaccine and getting vaccines against other diseases. You can get the COVID-19 vaccine on the same day as other vaccines. Talk with your healthcare professional to find out which vaccines you or your child need and when. It is also very important to get your flu vaccine. The flu is a contagious viral respiratory illness caused by influenza viruses, and it kills between 12,000 and 61,000 people each year. Young children, older adults, pregnant women, and people with chronic health conditions are most at risk of having serious complications from the flu.

It is important for people of all ages and communities to participate in clinical trials for COVID-19 treatments. This helps us find treatments and vaccines that are safe and effective for everybody. For more information about COVID-19 clinical trials, please visit the Clinical Trials page.