Vaccine Safety

Vaccines are safe and one of the best ways to protect yourself and your family from vaccine-preventable diseases. Vaccines are held to the highest standards of safety. For more information, click on the links below to read more about the safety of vaccines.

Explaining How Vaccines Work
Review how vaccines work, types of vaccines, and why some vaccines need more than one dose.

Vaccine Safety Information for Healthcare Providers
Connect with CDC’s resources about vaccine safety for healthcare providers, including storage and handling, recording adverse events, safety information by vaccine, and more.

How Vaccine Safety Monitoring Works
Learn how various systems work together to ensure the safety of vaccines.

Vaccine Safety Systems
Read about the CDC’s Immunization Safety Office’s major programs to monitor vaccine safety, including the Vaccine Adverse Events Reporting System (VAERS), the Vaccine Safety Datalink (VSD), and the Clinical Immunization Safety Assessment Project (CISA).

About Common Vaccine Safety Questions and Concerns
CDC answers common questions parents ask about vaccine safety.

Developing Safe and Effective Vaccines
Before a new vaccine is ever given to people, extensive lab testing is done that can take several years. Once testing in people begins, it can take several more years before clinical studies are complete and the vaccine is licensed