Key Things to Know About COVID-19 Vaccines

Help stop the pandemic by getting vaccinated

What we know

illustrations of vaccine, person wearing a mask, hand washing, and social distancing

Studies show that COVID-19 vaccines are effective at keeping you from getting COVID-19. Getting a COVID-19 vaccine will also help keep you from getting seriously ill even if you do get COVID-19.

COVID-19 vaccination is an important tool to help us get back to normal. Learn more about the benefits of getting vaccinated.

COVID-19 vaccines teach our immune systems how to recognize and fight the virus that causes COVID-19. It typically takes two weeks after vaccination for the body to build protection (immunity) against the virus that causes COVID-19. That means it is possible a person could still get COVID-19 before or just after vaccination and then get sick because the vaccine did not have enough time to provide protection.  People are considered fully protected two weeks after their second dose of the Pfizer-BioNTech or Moderna COVID-19 vaccine, or two weeks after the single-dose Johnson & Johnson’s Janssen COVID-19 vaccine.

You should keep using all the tools available to protect yourself and others until you are fully vaccinated. After you are fully vaccinated, you may be able to start doing some things you had stopped doing because of the pandemic. Learn more about what you can do when you have been fully vaccinated.

What we do not know

Although COVID-19 vaccines are effective at keeping you from getting sick, scientists are still learning how well vaccines prevent you from spreading the virus that causes COVID-19 to others, even if you do not have symptoms. Early data show the vaccines do help keep people with no symptoms from spreading COVID-19, but we are learning more as more people get vaccinated.

We’re also still learning how long COVID-19 vaccines protect people.

For these reasons, people who have been fully vaccinated against COVID-19 should keep taking precautions in public places, until we know more, like wearing a mask, staying 6 feet apart from others, avoiding crowds and poorly ventilated spaces, and washing your hands often.

COVID-19 vaccines are safe

Millions of people in the United States have received COVID-19 vaccines, and these vaccines have undergone the most intensive safety monitoring in U.S. history. This monitoring includes using both established and new safety monitoring systems to make sure that COVID-19 vaccines are safe. These vaccines cannot give you COVID-19. Learn more facts about COVID-19 vaccines.

CDC has developed a new tool, v-safe, to help us quickly find any safety issues with COVID-19 vaccines. V-safe is a smartphone-based, after-vaccination health checker for people who receive COVID-19 vaccines. Learn how the federal government is working to ensure the safety of COVID-19 vaccines.

You may have side effects after vaccination, but these are normal

After COVID-19 vaccination, you may have some side effects. These are normal signs that your body is building protection. The side effects from COVID-19 vaccination, such as chills or tiredness, may affect your ability to do daily activities, and they should go away in a few days. Learn more about what to expect after getting vaccinated.

In the coming months, vaccines will become widely available

Although the vaccine supply is currently limited, the federal government is working toward making vaccines widely available for everyone at no cost. Learn more about how COVID-19 vaccines get to you and CDC’s vaccine rollout recommendations.

Who pays for COVID-19 vaccines?

COVID-19 vaccination providers cannot:

  • Charge you for the vaccine
  • Charge you any administration fees, copays, or coinsurance
  • Deny vaccination to anyone who does not have health insurance coverage, is underinsured, or is out of network
  • Charge an office visit or other fee to the recipient if the only service provided is a COVID-19 vaccination
  • Require additional services in order for a person to receive a COVID-19 vaccine; however, additional healthcare services can be provided at the same time and billed as appropriate

COVID-19 vaccination providers can:

  • Seek appropriate reimbursement from the recipient’s plan or program (e.g., private health insurance, Medicare, Medicaid) for a vaccine administration fee
    • However, providers cannot charge the vaccine recipient the balance of the bill
  • Providers may also seek reimbursement for uninsured vaccine recipients from the Health Resources and Services Administration’s COVID-19 Uninsured Program.

In the coming months, doctors’ offices, retail pharmacies, hospitals, and clinics will offer COVID-19 vaccine. Your doctor’s office or local pharmacy may have contacted you with information about their vaccination plans. Use this tool to find more information on how to get vaccinated in your area:

To find COVID-19 vaccine locations near you: Search vaccines.gov, text your ZIP code to 438829, or call 1-800-232-0233.

When You’ve Been Fully Vaccinated

After you are fully vaccinated for COVID-19, you may be able to start doing some things that you had stopped doing because of the pandemic.

photo of woman receiving a vaccine

COVID-19 vaccines and herd immunity

What we know

vaccine doctor family shield

Herd immunity means that enough people in a community are protected from getting a disease because they’ve already had the disease or because they’ve been vaccinated. Herd immunity makes it hard for the disease to spread from person to person. It even protects those who cannot be vaccinated, like newborns or people who are allergic to the vaccine. The percentage of people who need to have protection to achieve herd immunity varies by disease.

What we do not know

We are still learning how many people have to be vaccinated against COVID-19 before most people can be considered protected. As we know more, CDC will continue to update our recommendations for both vaccinated and unvaccinated people.

COVID-19 vaccines and new variants of the virus

We are still learning how effective the vaccines are against new variants of the virus that causes COVID-19. Early data show the vaccines may work against some variants but could be less effective against others. We are learning more each day about the characteristics of new variants. CDC will share updates as soon as they are available.

For Healthcare Workers

Clinical Resources: Toolkits and resources for handling, storing and administering the vaccine, including patient education materials.

Content provided and maintained by the US Centers for Disease Control and Prevention (CDC). Please see our system usage guidelines and disclaimer.