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.

Ensuring COVID-19 Vaccines Work

Ensuring COVID-19 Vaccines Work
An illustrated image of two parents and a young child, all wearing masks, with the father holding a shield showing the word “vaccine” on the front.

COVID-19 Vaccines Work

  • Research provides evidence that COVID-19 vaccines are effective at preventing COVID-19.
  • COVID-19 vaccination is an important tool to help stop the COVID-19 pandemic.
  • COVID-19 vaccination helps protect adults and children ages 5 years and older from getting sick or severely ill with COVID-19 and helps protect those around them.
  • To receive the most protection, adults and children ages 5 years and older should receive all recommended doses of a COVID-19 vaccine.
  • Some people who are fully vaccinated against COVID-19 will still get sick because no vaccine is 100% effective. Experts continue to monitor and evaluate how often this occurs, how severe their illness is, and how likely a vaccinated person is to spread COVID-19 to others.
  • CDC recommends everyone ages 5 years and older get a COVID-19 vaccine as soon as one is available to you.

Do COVID-19 vaccines work?
Are COVID-19 vaccines safe?
What are breakthrough infections?

An illustrated image of two parents and a young child, all wearing masks, with the father holding a shield showing the word “vaccine” on the front.

Data on Vaccine Impact and Effectiveness

The latest data on rates of COVID-19 cases, hospitalizations and deaths by vaccination status are available from the CDC COVID Data Tracker

Rates of COVID-19 Cases by Vaccination Status
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For Healthcare Professionals and Health Departments