Important update: Healthcare facilities
CDC has updated select ways to operate healthcare systems effectively in response to COVID-19 vaccination. Learn more
UPDATE
Given new evidence on the B.1.617.2 (Delta) variant, CDC has updated the guidance for fully vaccinated people. CDC recommends universal indoor masking for all teachers, staff, students, and visitors to K-12 schools, regardless of vaccination status. Children should return to full-time in-person learning in the fall with layered prevention strategies in place.
UPDATE
The White House announced that vaccines will be required for international travelers coming into the United States, with an effective date of November 8, 2021. For purposes of entry into the United States, vaccines accepted will include FDA approved or authorized and WHO Emergency Use Listing vaccines. More information is available here.
UPDATE
Travel requirements to enter the United States are changing, starting November 8, 2021. More information is available here.

Frequently Asked Questions about COVID-19 Vaccination

Frequently Asked Questions about COVID-19 Vaccination

Below are answers to commonly asked questions about COVID-19 vaccination.

Have more questions? Visit How to Protect Yourself and Others and FAQs about COVID-19.

Boosters

Yes. Recent data suggest COVID-19 vaccine effectiveness at preventing infection or severe illness wanes over time, especially for certain groups of people,  such as people ages 65 years and older and people with immunocompromise.

The emergence of COVID-19 variants further emphasizes the importance of vaccination, boosters, and prevention efforts needed to protect against COVID-19.

Data show that an mRNA booster increases the immune response, which improves protection against getting a serious COVID-19 infection.

CDC recommends COVID-19 vaccines for everyone ages 6 months and older, and boosters for everyone 5 years and older, if eligible.

Learn more about COVID-19 vaccine recommendations, including recommendations for people who are moderately or severely immunocompromised. Use CDC’s COVID-19 Booster Tool to learn if and when you can get boosters to stay up to date with your COVID-19 vaccines.

Yes. COVID-19 vaccines are working well to prevent severe illness, hospitalization, and death. However, public health experts are seeing reduced protection over time against mild and moderate disease, especially among certain populations.

Yes. COVID-19 boosters are the same ingredients (formulation) as the current COVID-19 vaccines.

Adults and children may have some side effects from a COVID-19 vaccine, including pain, redness or swelling at the injection site, tiredness, headache, muscle pain, chills, fever, and nausea. Serious side effects are rare, but may occur.

Yes, the definition of fully vaccinated does not include a booster. Everyone, except those who are moderately or severely immunocompromised, is still considered fully vaccinated two weeks after their second dose in a two-dose series, such as the Pfizer-BioNTech and Moderna vaccines, or two weeks after the single-dose J&J/Janssen vaccine. Fully vaccinated, however, is not the same as having the best protection.  People are best protected when they stay up to date with COVID-19 vaccinations, which includes getting boosters when eligible.

You are up to date with your COVID-19 vaccines when you have received all doses in the primary series and all boosters recommended for you, when eligible. Learn more about COVID-19 booster recommendations.

People (except those who are moderately or severely immunocompromised) who first received a J&J/Janssen COVID-19 vaccine and got it again for their booster may also receive a booster of an mRNA COVID-19 vaccine (Pfizer-BioNTech or Moderna). Get the mRNA booster at least 4 months after the most recent J&J/Janssen booster.

  • One CDC study found that adults who received the J&J/Janssen COVID-19 vaccine as both their primary and booster had lower levels of protection against COVID-19-associated emergency department and urgent care visits during Omicron compared to adults who received an mRNA COVID-19 booster.\

Use CDC’s COVID-19 Booster Tool to learn if and when you can get boosters to stay up to date with your COVID-19 vaccines.

Getting Your Vaccine

An employer may require that their workers be vaccinated. Check directly with your employer to see if they have any vaccination requirements or rules that apply to you.

The number of vaccine doses you need to complete your primary series depends on which vaccine you receive.

  • 2 doses of Pfizer-BioNTech vaccine 3–8* weeks apart for people 5 years and older, or
  • 3 doses of Pfizer-BioNTech vaccine for ages 6 months through 4 years, first and second dose 3-8 weeks apart, second and third dose at least 8 weeks apart*.
  • 2 doses of Moderna vaccine 4–8* weeks apart for people ages 6 months and older.
  • 1 dose of Johnson & Johnson’s Janssen (J&J/Janssen) vaccine for people ages 18 and older.
  • 2 doses of Novavax vaccine 3-8* weeks apart for people ages 18 years and older.

*Talk to your healthcare or vaccine provider about the timing for the second dose in your primary series. You should not get the second dose early.

People who are moderately or severely immunocompromised may have a different immune response following COVID-19 vaccination. Please see specific COVID-19 vaccination guidance for people who are moderately or severely immunocompromised.

No. If you receive your second dose of a COVID-19 vaccine at any time after the recommended date, you do not have to restart the vaccine series. This guidance might be updated as more information becomes available.

Learn more about staying up to date with your COVID-19 vaccines.

Scientists are monitoring how long COVID-19 vaccine protection lasts. COVID-19 vaccines work well to prevent severe illness, hospitalization, and death. However, public health experts are seeing decreases in the protection COVID-19 vaccines provide over time, especially for certain groups of people. Due to this, CDC recommends COVID-19 vaccines for everyone ages 6 months and older, and boosters for everyone 5 years and older, if eligible. Learn more about COVID-19 booster recommendations, including recommendations for people who are moderately or severely immunocompromised.

CDC continues to review evidence and updates guidance as new information becomes available.

Results from recent research studies show that people who menstruate may observe small, temporary changes in menstruation after COVID-19 vaccination, including:

  • Longer duration of menstrual periods
  • Shorter intervals between periods
  • Heavier bleeding than usual

Despite these temporary changes in menstruation, there is no evidence that COVID-19 vaccines cause fertility problems.

Learn more about COVID-19 vaccination for people who would like to have a baby.

Safety

Although COVID-19 vaccines were developed quickly, research and development on vaccines like these have been underway for decades. All vaccine development steps were taken to ensure COVID-19 vaccine safety and effectiveness, including:

  • Clinical Trials – All vaccines in the United States must go through three phases of clinical trials to ensure they are safe and effective. The phases overlapped to speed up the process, but all phases were completed.
  • Authorization or Approval – Before vaccines are available to people, the U.S. Food and Drug Administration (FDA) reviews data from clinical trials. FDA has determined COVID-19 vaccines meet FDA’s standards and has granted those vaccines Emergency Use Authorizations (EUAs) or full FDA approval.
  • Tracking Safety Using Vaccine Monitoring Systems – Like every other vaccine approved for use in the United States, COVID-19 vaccines continue to be monitored for safety and effectiveness. Hundreds of millions of people in the United States have safely received COVID-19 vaccines. CDC and FDA continue to provide updated information on the safety of U.S. authorized or approved COVID-19 vaccines using data from several monitoring systems.

Learn more about developing COVID-19 vaccines.

Vaccine ingredients vary by manufacturer. None of the vaccines contain eggs, gelatin, latex, or preservatives. All COVID-19 vaccines are free from metals, such as iron, nickel, cobalt, lithium, and rare earth alloys. They are also free from manufactured products such as microelectronics, electrodes, carbon nanotubes, and nanowire semiconductors. None of the COVID-19 vaccines authorized or approved in the United States contain any live virus.

To learn more about the ingredients in authorized or approved COVID-19 vaccines, see

Yes, COVID-19 vaccination is recommended for people who are pregnant, breastfeeding, or trying to get pregnant now, as well as people who might become pregnant in the future. People with COVID-19 during pregnancy are more likely to deliver a preterm (earlier than 37 weeks) or stillborn infant and may also be more likely to have other pregnancy complications.

COVID-19 vaccination during pregnancy helps:

Learn more about vaccination considerations and the safety and effectiveness of COVID-19 vaccinations for people who are pregnant or breastfeeding.

If you are pregnant and have received a COVID-19 vaccine, we encourage you to enroll in v-safeCDC’s smartphone-based system that provides personalized health check-ins after vaccination. A v-safe pregnancy registry has been established to gather information on the health of pregnant people who have received a COVID-19 vaccine.

COVID-19 can make children and teens very sick and sometimes requires treatment in a hospital. Getting eligible children and teens vaccinated against COVID-19 can help keep them from getting really sick if they do get COVID-19, including protecting them from short and long-term complications and hospitalization. Vaccinating children can also help keep them in school or daycare and safely participating in sports, playdates, and other group activities.

The benefits of COVID-19 vaccination outweigh the known and potential risks. CDC recommends COVID-19 vaccines for everyone ages 6 months and older, and boosters for everyone 5 years and older, if eligible.

Learn 6 Things About the COVID-19 Vaccine for Children.

Use CDC’s COVID-19 Booster Tool to learn if and when your child or teen can get boosters to stay up to date with their COVID-19 vaccines.

Preparing for Your Vaccine

COVID-19 vaccination significantly lowers your risk of severe illness, hospitalization, and death if you get infected. Compared to people who are up to date with their COVID-19 vaccinations, unvaccinated people are more likely to get COVID-19, much more likely to be hospitalized with COVID-19, and much more likely to die from COVID-19.

Like all vaccines, COVID-19 vaccines are not 100% effective at preventing infection. Some people who are up to date with their COVID-19 vaccinations will get COVID-19 breakthrough infection. However, staying up to date with your COVID-19 vaccinations means that you are less likely to have a breakthrough infection and, if you do get sick, you are less likely to get severely ill or die. Staying up to date with COVID-19 vaccination also means you are less likely to spread the disease to others and increases your protection against new variants of SARS-CoV-2, the virus that causes COVID-19.

There is no recommended waiting period between getting a COVID-19 vaccine and other vaccines. You can get a COVID-19 vaccine and other vaccines, including a flu vaccine, at the same visit. Experience with other vaccines has shown that the way our bodies develop protection, known as an immune response, and possible side effects after getting vaccinated are generally the same when given alone or with other vaccines.

You should get a COVID-19 vaccine even if you already had COVID-19.

Getting a COVID-19 vaccine after you recover from COVID-19 infection provides added protection against COVID-19. You may consider delaying your vaccine by 3 months from when your symptoms started or, if you had no symptoms, when you received a positive test.

People who already had COVID-19 and do not get vaccinated after their recovery are more likely to get COVID-19 again than those who get vaccinated after their recovery.

Learn more about the benefits of getting a COVID-19 vaccine.

No. You should wait to be vaccinated until after you complete your isolation period. People who have symptoms will end isolation at a different time than people who do not have symptoms. This also applies to people who have been vaccinated but get COVID-19 before getting any additional or booster doses. Additionally, you may consider delaying your next vaccine (primary dose or booster) by 3 months from when your symptoms started or, if you had no symptoms, when you received a positive test.

People who have had a known COVID-19 exposure should not seek vaccination until their quarantine period has ended to avoid potentially exposing healthcare personnel and others during the vaccination visit. This recommendation to wait also applies to people with a known COVID-19 exposure who have received their first dose and need additional or booster doses.

Learn more about how to stay up to date with your COVID-19 vaccines.

Yes, depending on your age, you can choose which COVID-19 vaccine to get.

Learn more about which vaccine is available by age and how to stay up to date with your COVID-19 vaccination.

After Your Vaccine

If you have lost your CDC COVID-19 Vaccination card or don’t have a copy of it, contact your vaccination provider directly to request a new vaccination card. They may be able to reissue a CDC COVID-19 Vaccination card.

  • If you cannot contact your vaccination provider directly or your vaccination provider cannot reissue a CDC COVID-19 Vaccination card, contact your state health department’s immunization information system (IIS). Your state’s IIS cannot issue you a vaccination card, but they can provide a digital or paper copy of your full vaccination record, including your COVID-19 vaccinations.
  • If you need another COVID-19 vaccine dose and are unable to get a copy of your vaccination card or vaccination record, talk to a vaccination provider to learn about your possible options.
  • Some vaccination providers and health departments may offer you access to a QR code or digital copy of your CDC COVID-19 Vaccination card in addition to giving you a physical card. Contact your vaccination provider or local health department to learn if you can get a digital copy of your card.

CDC does not provide the white CDC COVID-19 Vaccination card to people and does not maintain vaccination records. CDC distributes the white CDC COVID-19 Vaccination cards to vaccination providers and only a vaccination provider can give you this card.

Generally, if you are up to date on your COVID-19 vaccinations, you do not need to wear a mask in outdoor settings. Check your local COVID-19 Community Level for recommendations on when to wear a mask indoors and additional precautions you can take to protect yourself from COVID-19. If you are immunocompromised or more likely to get very sick from COVID-19, learn more about how to protect yourself.

If you have a condition or are taking medications that weaken your immune system, your immune response to COVID-19 vaccination may not be as strong as in people who are not immunocompromised. Check your county’s COVID-19 Community Level for recommendations on whether you should wear a mask and additional actions you can take to protect yourself from COVID-19. You may choose to wear a mask at any time based on your own level of comfort and personal risk.

Learn more about COVID-19 vaccinations for people who are moderately or severely immunocompromised.

The white CDC COVID-19 vaccination cards are only issued to people vaccinated in the United States. However, there are several ways you can update your records with vaccines you received while outside the United States. Learn more about COVID-19 Vaccines for People Who Were Vaccinated Abroad.

It depends on a number of factors. Learn more about COVID-19 Vaccines for People Who Were Vaccinated Abroad.

CDC does not keep vaccination records or determine how vaccination records are used. To update your records with vaccines you received while outside of the United States, you may:

  • Contact the immunization information system (IIS) in your state. You can find state IIS information on the CDC website. 
  • Contact your healthcare provider or your local or state immunization program through your state’s health department.

The CDC-labeled white COVID-19 Vaccination Record Cards are only issued to people vaccinated in the United States. CDC recommends you keep your documentation of being vaccinated in the other country as proof of vaccination. CDC also recommends checking with your primary care provider or state health department for options to document your vaccination status domestically.

If you have received all recommended doses of a COVID-19 vaccine that has been authorized or approved by the U.S. Food and Drug Administration (FDA) or is listed for emergency use by the World Health Organization (WHO), then you are considered to be fully vaccinated. This currently includes the following vaccines:

  • Pfizer-BioNTech COVID-19 Vaccine – FDA-authorized, (labeled as COMIRNATY in European Union), 2 doses, for adolescents 12 -15 years old
  • Pfizer-BioNTech (COMIRNATY) COVID-19 Vaccine – FDA-approved, 2 doses, for persons 16 years and older
  • Moderna COVID-19 Vaccine – FDA-authorized, 2 doses, for persons 18 years and older
  • Johnson and Johnson’s Janssen COVID-19 Vaccine – FDA-authorized, (labeled as Janssen-Cilag in European Union), 1 dose, for persons 18 years and older
  • AstraZeneca COVID-19 Vaccine – WHO-listed, (labeled as COVISHIELD in Canada and others, labeled as AstraZeneca/SKBio in Republic of Korea), 2 doses, for persons 18 years and older
  • Sinopharm BIBP COVID-19 Vaccine – WHO-listed, 2 doses, for persons 18 years and older
  • Sinovac-CoronaVac COVID-19 Vaccine – WHO-listed, 2 doses, for persons 18 years and older

If you received a COVID-19 vaccine that is not authorized or approved by FDA or listed for emergency use by WHO, you may start over with an FDA-authorized or approved COVID-19 vaccine. Please note that no data are available on the safety or effectiveness of COVID-19 vaccination after receiving a non-FDA-authorized or approved COVID-19 vaccine. Wait at least 28 days after you received the last dose of the non-FDA-authorized or approved vaccine before receiving an FDA-authorized or approved COVID-19 vaccine.

Visit the clinical considerations webpage for more information.

While COVID-19 vaccines were developed rapidly, all steps were taken to make sure they are safe and effective:

  • Approach to Development – Scientists have been working for many years to develop vaccines against viruses like the one that causes COVID-19. This knowledge helped speed up the initial development of the current COVID-19 vaccines.
  • Clinical Trials – All vaccines in the United States must go through three phases of clinical trials to make sure they are safe and effective. During the development of COVID-19 vaccines, phases overlapped to speed up the process, but all phases were completed.
  • Authorization or Approval – Before vaccines are available to people, the U.S. Food and Drug Administration (FDA) assesses the findings from clinical trials. FDA determined that three COVID-19 vaccines met FDA’s safety and effectiveness standards and granted those vaccines Emergency Use Authorizations (EUAs). This allowed the vaccines to be quickly distributed to control the pandemic. Pfizer-BioNTech (COMIRNATY) COVID-19 vaccine has now been FDA approved for people ages 16 years and older. Read more about the first COVID-19 vaccine to receive FDA approval.
  • Manufacturing and Distribution – The U.S. government has invested substantial resources to manufacture and distribute COVID-19 vaccines. This allowed vaccine distribution to begin as soon as FDA authorized each vaccine.
  • Tracking Safety Using Vaccine Monitoring Systems – COVID-19 vaccine safety monitoring has been the most intense and comprehensive in U.S. history. Hundreds of millions of people in the United States have received COVID-19 vaccines. Through several monitoring systems, CDC and FDA continue to provide updated information on the safety of these vaccines.

Learn more about developing COVID-19 vaccines.

You can get a COVID-19 vaccine and other vaccines, including a flu vaccine, at the same visit. Experience with other vaccines has shown that the way our bodies develop protection, known as an immune response, and possible side effects after getting vaccinated are generally the same when given alone or with other vaccines. Learn more about the timing of other vaccines.

Yes, you should be vaccinated regardless of whether you already had COVID-19 because:

  • Research has not yet shown how long you are protected from getting COVID-19 again after you recover from COVID-19.
  • Vaccination helps protect you even if you’ve already had COVID-19.

Evidence is emerging that people get better protection by being fully vaccinated compared with having had COVID-19. One study showed that unvaccinated people who already had COVID-19 are more than 2 times as likely than fully vaccinated people to get COVID-19 again.

If you were treated for COVID-19 with monoclonal antibodies or convalescent plasma, you should wait 90 days before getting a COVID-19 vaccine. Talk to your doctor if you are unsure what treatments you received or if you have more questions about getting a COVID-19 vaccine.

If you or your child has a history of multisystem inflammatory syndrome in adults or children (MIS-A or MIS-C), consider delaying vaccination until you or your child have recovered from being sick and for 90 days after the date of diagnosis of MIS-A or MIS-C. Learn more about the clinical considerations for people with a history of multisystem MIS-C or MIS-A.

Experts are still learning more about how long vaccines protect against COVID-19. CDC will keep the public informed as new evidence becomes available.

Related pages:

No. People with COVID-19 who have symptoms should wait to be vaccinated until they have recovered from their illness and have met the criteria for discontinuing isolation; those without symptoms should also wait until they meet the criteria before getting vaccinated. This guidance also applies to people who get COVID-19 before getting their second dose of vaccine.

People who have had a known COVID-19 exposure should not seek vaccination until their quarantine period has ended to avoid potentially exposing healthcare personnel and others during the vaccination visit. This recommendation also applies to people with a known COVID-19 exposure who have received their first dose of an mRNA vaccine but not their second.

Related pages:

Vaccine ingredients vary by manufacturer. None of the vaccines contain eggs, gelatin, latex, or preservatives. All COVID-19 vaccines are free from metals such as iron, nickel, cobalt, lithium, and rare earth alloys. They are also free from manufactured products such as microelectronics, electrodes, carbon nanotubes, or nanowire semiconductors.

To learn more about the ingredients in authorized COVID-19 vaccines, see

We don’t know how long protection lasts for those who are vaccinated. What we do know is that COVID-19 has caused very serious illness and death for a lot of people. If you get COVID-19, you also risk giving it to loved ones who may get very sick.

People with moderately to severely compromised immune systems should receive an additional primary dose of mRNA COVID-19 vaccine after the initial 2 doses.

Learn more about population immunity.

 

Related pages:

If you need a new vaccination card, contact the vaccination provider site where you received your vaccine. Your provider should give you a new card with up-to-date information about the vaccinations you have received.

If the location where you received your COVID-19 vaccine is no longer operating, contact your state or local health department’s immunization information system (IIS) for assistance.

CDC does not maintain vaccination records or determine how vaccination records are used, and CDC does not provide the CDC-labeled, white COVID-19 vaccination record card to people. These cards are distributed to vaccination providers by state and local health departments. Please contact your state or local health department if you have additional questions about vaccination cards or vaccination records.

Related page:

Yes. All currently authorized and recommended COVID-19 vaccines are safe and effective, and CDC does not recommend one vaccine over another. The most important decision is to get a COVID-19 vaccination as soon as possible. Widespread vaccination is a critical tool to help stop the pandemic.

People should be aware that a risk of a rare condition called thrombosis with thrombocytopenia syndrome (TTS) has been reported following vaccination with the J&J/Janssen COVID-19 Vaccine. TTS is a serious condition that involves blood clots with low platelet counts. This problem is rare, and most reports were in women between 18 and 49 years old. For women 50 years and older and men of any age, this problem is even more rare. There are other COVID-19 vaccine options available for which this risk has not been seen (Pfizer-BioNTech, Moderna).

Learn more about your COVID-19 vaccination, including how to find a vaccination location, what to expect at your appointment, and more.

Related page:

After you are fully vaccinated for COVID-19, take these steps to protect yourself and others:

People with underlying medical conditions can receive a COVID-19 vaccine as long as they have not had an immediate or severe allergic reaction to a COVID-19 vaccine or to any of the ingredients in the vaccine. Learn more about vaccination considerations for people with underlying medical conditions. Vaccination is an important consideration for adults of any age with certain underlying medical conditions because they are at increased risk for severe illness from COVID-19.

Related pages:

Yes, COVID-19 vaccination is recommended for people who are pregnant, breastfeeding, trying to get pregnant now, or who might become pregnant in the future. You might want to have a conversation with your healthcare provider about COVID-19 vaccination. While such a conversation might be helpful, it is not required before vaccination. Learn more about vaccination considerations for people who are pregnant or breastfeeding.

If you are pregnant and have received a COVID-19 vaccine, we encourage you to enroll in v-safeCDC’s smartphone-based tool that provides personalized health check-ins after vaccination. A v-safe pregnancy registry has been established to gather information on the health of pregnant people who have received a COVID-19 vaccine.

Related pages:

The number of doses needed depends on which vaccine you receive. To get the most protection:

  • Two Pfizer-BioNTech vaccine doses should be given 3 weeks (21 days) apart.
  • Two Moderna vaccine doses should be given 1 month (28 days) apart.
  • Johnson & Johnsons Jansen (J&J/Janssen) COVID-19 vaccine requires only one dose.

If you receive a vaccine that requires two doses, you should get your second shot as close to the recommended interval as possibleHowever, your second dose may be given up to 6 weeks (42 days) after the first dose. You should not get the second dose earlier than the recommended interval.

People with moderately to severely compromised immune systems should receive an additional primary dose of mRNA COVID-19 vaccine after the initial 2 doses.

 

Related pages:

COVID-19 vaccination can help protect your child from getting COVID-19. Although fewer children have been sick with COVID-19 compared to adults, children can be infected with the virus that causes COVID-19, can get sick from COVID-19, and can spread the virus that causes COVID-19 to others. Getting your child vaccinated helps to protect your child and your family. Vaccination is now recommended for everyone 12 years and older. Currently, the Pfizer-BioNTech COVID-19 Vaccine is the only one available to children 12 years and older.

COVID-19 vaccines have been used under the most intensive safety monitoring in U.S. history, including studies in children 12 years and older. Your child cannot get COVID-19 from any COVID-19 vaccine. Like adults, children may have some side effects after COVID-19 vaccination. These side effects may affect their ability to do daily activities, but they should go away in a few days.

Related pages: