Skip to Content
Your browser is out of date. To use this website, please update your browser or use a different device.
U.S. flag

An official website of the United States government

About COVID-19 vaccines

Read this page to learn more about how COVID-19 vaccines protect you and how we know they’re safe. And get more information about COVID-19 vaccines during pregnancy and breastfeeding.

Why to get a COVID-19 vaccine

  • Data shows that even younger people are getting sick from the virus that causes COVID-19. Young Black and Hispanic people are at increased risk. This increased risk is due to racial health inequities and other factors that can affect a person’s health. These include factors like the environment where the person lives or their ability to access health care.
  • There is no cure for COVID-19 at this time. There are treatments for COVID-19, but the risk of severe illness and death are still high in certain groups of people. And the Centers for Disease Control and Prevention (CDC) reports that some of the treatments we use to treat COVID-19 may not work as well against the new form of the coronavirus known as the “Delta variant.” Talk to your health care provider before taking any medications to prevent or treat COVID-19. 
    Learn more about COVID-19 treatments on the CDC website
    Get answers to your questions about COVID-19 treatments

  • Some people report long-term effects of COVID-19. Most people get better in weeks. But some people have effects that last for a longer time. These effects may include symptoms like dizziness, depression, or feeling very tired. They may also include effects on vital organs like your heart or lungs. The effects can happen even after a mild illness.
    Learn more about long-term COVID-19 effects on the CDC website
  • When you get a COVID-19 vaccine, you help protect your family, friends, and community. When enough people in a community get the vaccine, the community builds up immunity to the virus. This makes it harder for the virus to spread from person to person. And it protects those who can’t get a vaccine (like small children). We call this “community immunity.”
  • After you’re fully vaccinated, you can start to do more. This may include visiting with family. It may include not having to wear a mask except where required by law or other rules. It may also include traveling without the need for a COVID-19 test.
    Read the CDC guidelines for after you’re fully vaccinated
  • You can get a free COVID-19 vaccine—even if you don’t have health insurance.
    Find out how to get a COVID-19 vaccine at VA
    Find COVID-19 vaccines near you on the CDC website

Vaccine effectiveness

Scientists studied the 3 Food and Drug Administration (FDA) approved or authorized COVID-19 vaccines in tens of thousands of people in clinical trials. The trials included people of all ages, genders, races, and ethnicities. Scientists continue to study these vaccines as millions of people get vaccinated.  

Results show that the vaccines work well in these ways:

  • The vaccines help protect you from getting COVID-19. Vaccines help train your body’s natural immune system to recognize and fight a specific disease by stimulating a response to the virus that causes that disease. 
  • Even if you get COVID-19, the vaccines help protect you from getting severe illness. Severe illness may mean having to go to the hospital, needing a ventilator to breathe, or having an illness that results in death.
  • The vaccines offer good protection against the COVID-19 variants that we know most about, including the Delta variant. Variants are new forms of the virus that causes COVID-19. The Delta variant spreads more easily and quickly than other variants. It might also cause more severe illness than earlier variants in people who aren't fully vaccinated.

We’re still learning about how long vaccines protect you from COVID-19. We’re also still learning how well vaccines protect you from spreading the virus that causes COVID-19. Early data shows that vaccines do help keep people with no symptoms from spreading the virus.

Learn more about COVID-19 vaccine effectiveness on the CDC website

Learn more about how COVID-19 vaccines work on the CDC website


Vaccine safety

Here’s how we know that COVID-19 vaccines are safe:

  • Scientists studied COVID-19 vaccines in tens of thousands of people in clinical trials. These trials showed no serious safety concerns. The trials included people of all ages, genders, races, and ethnicities. 
  • All the current vaccines have met the FDA’s high safety standards. Before the FDA approves or authorizes a vaccine for use, they review all safety data and clinical trial results. They also review the process a company uses to make the vaccine. They make sure the process follows quality and safety standards.
  • Millions of people in the United States have now received COVID-19 vaccines. Serious safety problems are rare. The monitoring systems have found only 2 serious health problems after vaccination. Both of these health problems are rare.
    Learn more about these rare problems on the CDC website
  • COVID-19 vaccines continue to undergo the most intense safety monitoring in U.S. history. The FDA and CDC respond right away if data shows a vaccine may cause health problems—no matter how rare. 

Learn more about COVID-19 vaccine safety on the CDC website

Go to the CDC video on COVID-19 vaccine safety (YouTube)


Vaccines during pregnancy or breastfeeding

The CDC and other experts strongly recommend that people who are pregnant, planning to become pregnant, or breastfeeding get a COVID-19 vaccine.

Risks of COVID-19 during pregnancy

Here’s what we know about the risks of COVID-19 during pregnancy and how vaccines can help:

  • Pregnant people are at increased risk of severe illness from COVID-19. Severe illness may mean having to go to the hospital, needing a ventilator to breathe, or having an illness that results in death. Pregnant people also have an increased risk of preterm birth. These risks are highest for Black and Hispanic people who are pregnant and sick with COVID-19.
  • COVID-19 vaccines can help protect you from COVID-19. Even if you do get COVID-19, a vaccine can help protect you from severe illness.
  • COVID-19 vaccination in a pregnant or breastfeeding person may provide some protection to their newborn. Some immunity may pass to the newborn through the placenta and through human milk.

COVID-19 vaccine safety during pregnancy and breastfeeding

Here’s what we know about COVID-19 vaccine safety in people who are pregnant, planning to become pregnant, or breastfeeding:

  • You don’t need to get a pregnancy test before you get a COVID-19 vaccine. The FDA approved or authorized COVID-19 vaccines don’t have ingredients that we know to be harmful people who are pregnant or to a developing fetus.
  • Experts believe that COVID-19 vaccines are safe for people who are pregnant or planning to become pregnant and their babies. Early safety data for mRNA COVID-19 vaccines (Pfizer-BioNTech and Moderna) suggest that there are no increased risks of miscarriage or harm to pregnant women or their babies.
  • Experts believe that COVID-19 vaccines are safe for people who are breastfeeding and their babies. Early safety data for mRNA COVID-19 vaccines (Pfizer-BioNTech and Moderna) suggest that there are no increased risks to people who breastfeed or chestfeed. You do not have to delay or stop breastfeeding to get the vaccine.

  • There’s no evidence that COVID-19 vaccines affect fertility among the millions of people who’ve received the vaccines so far. If you’re planning or trying to get pregnant, you can get a COVID-19 vaccine. If you find out you’re pregnant after you get your first dose of a vaccine that requires 2 doses, you should still get the second dose.

  • If you have a fever after you get your vaccine, you should take acetaminophen (Tylenol®). Fever, for any reason, during pregnancy has been associated with adverse pregnancy outcomes.

Note: Women younger than 50 years old should be aware of the rare risk of blood clots with low platelets after getting the Janssen (Johnson & Johnson) vaccine.

Learn more about the Janssen vaccine on the CDC website

More information about COVID-19 vaccines and pregnancy

Download our COVID-19 and women’s health fact sheet (PDF)

Read the CDC’s health advisory on vaccines and pregnancy on the CDC website

Learn more about COVID-19 vaccines, pregnancy, and breastfeeding on the CDC website

You can also talk with your health care provider about getting your vaccine. Your provider is always the best person to answer questions about your unique health needs.

Send a secure message to your VA health care provider


More facts about COVID-19 vaccines

mRNA vaccines that protect you from COVID-19 don’t alter your DNA. These vaccines work outside of your cell’s nucleus (where your DNA is kept). The vaccines teach your cells how to make a protein that triggers an immune response. Your cells then break down the mRNA and get rid of it soon after they’ve finished using the instructions.

Learn more about mRNA vaccines on the CDC website

The current COVID-19 vaccines, and the vaccines still in development, use one of these methods:

  • An inactivated virus
  • A harmless piece of the virus
  • A gene from the virus

None of these can cause COVID-19.

Learn more about how COVID-19 vaccines work on the CDC website

COVID-19 vaccines offer good protection against the variants we know most about. And widespread vaccination can prevent deaths and hospitalizations from COVID-19.

Current vaccines may not offer as much protection against future variants. But with the new types of vaccines that we have now, we can adjust the vaccines to fight new variants. Until we achieve high levels of vaccination around the world, we expect more variants to arise. 

Here’s what we know about the new variant known as the “Delta variant” that’s now spreading across the U.S.:

  • The Delta variant spreads more easily and quickly than other variants. 
  • The CDC reports that some of the medical treatments we use to treat COVID-19 may not work as well against this variant. 
  • People who haven’t gotten a vaccine—or have only gotten their first of a 2-dose vaccine series—are at highest risk. Getting your second dose is critical. There are reports of people who’ve received only one dose and got very sick from COVID-19. 

Get the latest facts about COVID-19 variants from the CDC website

How vaccines protect you

Vaccines help train your body’s natural immune system to recognize and fight a specific disease by stimulating a response to the virus that causes that disease.

When a virus is introduced to your body for the first time, your immune system mounts a defense. This includes making antibodies that help kill or neutralize the virus. If you’re exposed to the same virus again, these antibodies also help your immune system recognize and fight the virus quickly.

Learn more about how COVID-19 vaccines work on the CDC website

How vaccines protect the people around you

Protecting whole communities from diseases like COVID-19 is an important reason for everyone to get vaccines. We call this “community immunity.”

When enough people are vaccinated and develop immunity to a certain virus, that virus can’t spread as easily from person to person. This means that everyone in the community is less likely to get infected. Even if some people do still get infected, there’s less chance of an outbreak that causes many people in the community to get sick at the same time. This helps prevent issues like too many people needing care at once and not having enough hospital beds or health care providers.

Data shows that some communities have been disproportionately affected by COVID-19. These include Black, Hispanic, Native American, Pacific Islander, and Asian communities. Members of these communities can help protect their families and friends by getting vaccinated.

Data from clinical trials show that the 3 authorized COVID-19 vaccines are safe in people who’ve been infected with the virus that causes COVID-19 in the past. 

If you’re currently sick from COVID-19, you should wait until you’ve recovered, and you’re finished with isolation to get a vaccine.

If you’ve received passive antibody therapy to treat COVID-19, you should wait at least 90 days before getting a COVID-19 vaccine.

Go to the CDC website for answers to more common questions about COVID-19 vaccines

Here’s what you should know about how scientists created and tested COVID-19 vaccines so quickly:

  • They built on earlier work. Scientists have been studying vaccines for more than 100 years. Scientists have been studying the technology for mRNA vaccines for more than 20 years. And the National Institutes of Health (NIH) was working on creating a coronavirus vaccine even before the COVID-19 pandemic.
  • They got the funding they needed to work quickly. The COVID-19 pandemic is a public health emergency. So the U.S. government invested millions of dollars to help study and test vaccines.
  • They used a faster review process with all the same steps. The FDA authorized the current COVID-19 vaccines under their Emergency Use Authorization (EUA). An EUA follows the same steps that full-term clinical trials take. This includes testing each vaccine on thousands of human participants. The only difference is that an EUA speeds up the FDA’s review process. This helps get critical vaccines to people faster while still making sure the vaccines are safe and that they work well.
  • They involved many experts in reviewing data. Independent groups also reviewed trial results to make sure the vaccines are safe. These include groups like the National Medical Association, the leading professional society of Black doctors.

The FDA continues to monitor COVID-19 vaccines even after they’re approved.

Play this FDA video to learn more about the EUA process (YouTube)

 

Last updated: