Vaccine Safety Monitoring at CDC
Why it's Important to Monitor Vaccine Safety
CDC is committed to ensuring that vaccines provided to the public are safe and effective. Once vaccines are licensed in the United States, CDC actively monitors the safety of these vaccines through several systems. If any vaccine is found to cause health problems, the vaccine may be withdrawn and no longer given to the public.
Through vaccine safety monitoring, we also make sure new vaccines are safe for people who are at high risk of complications if they get a disease, such as the elderly, those with chronic medical conditions, and pregnant women. In some cases, these high-risk groups may not be included in clinical trials [PDF - 290 KB] so it is critical to monitor the safety of vaccines in these populations.
Vaccine Safety Monitoring Activities
CDC ensures the safety of vaccines by:
- Conducting vaccine safety research, done by the nation’s leading vaccine safety experts.
- Assessing what could be the cause of an adverse event and identifying any potential risk factors.
- Searching for adverse events following immunization (AEFIs) in multiple ways, mainly using three safety surveillance systems which each provide different insight into the vaccine use in the US population.
CDC’s Immunization Safety Office conducts 3 primary vaccine safety activities:
- The Vaccine Adverse Event Reporting System (VAERS) –an early warning public health system where people can report vaccine concerns, that helps CDC and FDA detect possible side effects or adverse events following vaccination.
- The Vaccine Safety Datalink (VSD) –a collaboration between CDC and several healthcare organizations which uses de-identified health records to monitor and evaluate adverse events following vaccination.
- The Clinical Immunization Safety Assessment (CISA) Network –a collaboration between CDC and several medical research centers in the United States to conduct research into how on adverse events might be caused by vaccines.
Vaccine safety monitoring continues to become more important with the development and use of new vaccines, expanded vaccine recommendations, and new global immunization initiatives. Reporting systems and vaccine safety activities, such as VAERS, VSD, and CISA, will continue to be used to monitor and study adverse events, so vaccines can continue to be held to very high standards of safety.
Read more: History of vaccine safety
- The Journey of Your Child’s Vaccine – from vaccine development to safety monitoring.
- FDA’s Mini-Sentinel – monitoring the safety of FDA-regulated medical products.
- FDA Vaccines, Blood & Biologics – vaccine information, vaccine safety and availability.