Monitoring health problems after vaccination is essential to ensure the United States continues to have the safest, most effective vaccine supply in history.
CDC's Immunization Safety Office identifies possible vaccine side effects and conducts studies to determine whether a health problem is caused by a specific vaccine.
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MMR Vaccine Safety
The measles, mumps, and rubella (MMR) vaccine is considered very safe; very few serious side effects have been reported.
Rapid Cycle Analysis (RCA)
This active surveillance system is designed to detect adverse events (possible side effects) following vaccination very quickly.
Centers for Disease Control and Prevention
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