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Vaccine Safety Monitoring
CDC monitors the safety of vaccines by:
- Performing high-quality vaccine safety research.
- Making determinations about whether vaccines caused reactions in certain cases and helping to learn about preventable risk factors.
- Identifying vaccine adverse events through public health surveillance.
CDC’s Immunization Safety Office conducts four primary vaccine safety activities:
Vaccine Adverse Event Reporting System (VAERS)
An early warning system that helps CDC and FDA monitor problems following vaccination. Anyone can report suspected vaccine reactions and issues to VAERS.
Clinical Immunization Safety Assessment (CISA) Project
A partnership between CDC and several medical centers that conduct clinical research on vaccine-associated health risks in certain groups of people.
Vaccine Safety Datalink (VSD)
A collaboration between CDC and several health care organizations that allows ongoing monitoring and proactive searches of vaccine-related data.
Emergency Preparedness for Vaccine Safety
In the event of a disease outbreak in which a mass vaccination campaign is needed, CDC activates emergency preparedness activities to ensure that vaccines remain safe.