Important update: Healthcare facilities
CDC has updated select ways to operate healthcare systems effectively in response to COVID-19 vaccination. Learn more
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.
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.
Travel requirements to enter the United States are changing, starting November 8, 2021. More information is available here.

Ensuring COVID-19 Vaccine Safety in the US

Ensuring COVID-19 Vaccine Safety in the US
Updated Dec. 22, 2022
vaccine vial

Vaccine Safety and Monitoring

  • COVID-19 vaccines were developed using science that has been around for decades.
  • COVID-19 vaccines are safe, and meet the Food and Drug Administration’s (FDA’s) rigorous scientific standards for safety, effectiveness, and manufacturing quality.
  • COVID 19-vaccines are effective at preventing severe illness from COVID-19 and limiting the spread of the virus that causes it.
  • Millions of people in the United States have received COVID-19 vaccines.
  • COVID-19 vaccines are monitored by the most intense safety monitoring efforts in U.S. history.

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

  • Children and teens ages 6 months–17 years
  • Adults ages 18 years and older

Are the vaccines safe?
Have vaccines caused any health problems?

vaccine vial

To make sure that COVID-19 vaccines are safe, CDC expanded and strengthened the country’s ability to monitor vaccine safety. CDC created new web-based platforms to gather more information about the safety of COVID-19 vaccines. These platforms give CDC scientists information about the safety of COVID-19 vaccines in real time.

As a result, vaccine safety experts can monitor and detect issues that may not have been seen during the COVID-19 vaccine clinical trials. If any vaccine safety issues—also called adverse events— are reported, CDC scientists can quickly study them and determine if there is a safety concern with a particular vaccine.

Here are some of the tools that CDC uses to keep close tabs on the safety of COVID-19 vaccines: