Vaccine Safety

All vaccines used in the United States are required to go through years of extensive safety testing before they are licensed by the US Food and Drug Administration (FDA). FDA and the Centers for Disease Control and Prevention (CDC) work with healthcare providers throughout the US to monitor the safety of vaccines, including for any adverse events, especially rare events not identified in pre-licensure study trials. There are currently three systems used to monitor the safety of vaccines after they are licensed and being used in the US. These systems can monitor side effects already known to be caused by vaccines as well as detect rare side effects that were not identified during a vaccine’s clinical trials.

One of the  three systems used to monitor the safety of vaccines after they are licensed and used in the US is the Vaccine Adverse Event Reporting System (VAERS). VAERS accepts reports from health professionals, vaccine manufacturers, and the general public and receives about 28,000 US reports per year, compared with millions of vaccine doses given to adults.