What to know
- Hundreds of millions of people in the United States have safely received COVID-19 vaccinations.
- COVID-19 vaccines used in the response to the pandemic underwent the most intensive safety monitoring in U.S. history. Safety monitoring used established systems.
- CDC provides timely updates on selected adverse events (any side effect or health problem after vaccination that is concerning to you, even if you are not sure if the vaccine caused the event) reported to VAERS after COVID-19 vaccination.
Monitoring process
After a vaccine is authorized or approved for use, vaccine safety systems monitor adverse events (rare health conditions) and watch for potential safety problems.
Keep Reading:
About CDC’s Vaccine Safety Monitoring Program
COVID-19 vaccines have undergone the most extensive safety analysis in U.S. history. The U.S. FDA COVID-19 Vaccines website includes important recommendations for ongoing safety evaluations after any COVID-19 vaccine is made available under Emergency Use Authorization (EUA) or receives full FDA approval.
Monitoring systems
The following system and information sources were developed during the COVID-19 pandemic. They add an additional layer of safety monitoring, giving CDC and FDA the ability to evaluate COVID-19 vaccine safety in real time and make sure COVID-19 vaccines are as safe as possible.
General public
- CDC's v-safe After Vaccination Health Checker: a smartphone-based platform for people and their dependents who receive COVID-19 vaccines.
- Vaccine Adverse Event Reporting System (VAERS)
- The Vaccine Safety Datalink (VSD)
- CDC's Clinical Immunization Safety Assessment (CISA) Project
- The Centers for Medicare and Medicaid Services (CMS) Medicare Claims database: looks for any vaccine-related claims among Medicare participants aged 65 years and older. FDA then shares this information with CDC.
- FDA's Biologics Effectiveness and Safety (BEST) System: a system of electronic health records, administrative, and claims-based data for active surveillance and research.
People who are pregnant
- The V-safe COVID-19 Vaccine Pregnancy Registry: a registry to collect additional health information from v-safe participants who report being pregnant at the time of vaccination or a positive pregnancy test after vaccination. This information helps CDC monitor the safety of COVID-19 vaccines in people who are pregnant.
- CDC's Birth Defects Study to Evaluate Pregnancy Exposures (BD-STEPS): an ongoing study that collects information, including COVID-19 vaccination information, from people who have recently been pregnant to understand the potential causes of birth defects and how to prevent them.
- VAERS
- VSD
- CDC's CISA Project
Members of the military
- Department of Defense's (DOD's) VAERS data: spontaneous adverse event reporting to VAERS for the DOD population.
- DOD's Vaccine Adverse Event Clinical System (VAECS): a system for case tracking and evaluation of adverse events following immunization in DOD and DOD-affiliated populations.
- DOD's Electronic Health Record and Defense Medical Surveillance System: large, linked electronic health records (AHLTA/MHS GENESIS) and administrative data systems for near real-time safety monitoring and research.
Veterans
- Department of Veterans Affairs (VA) Adverse Drug Event Reporting System (VA ADERS): a national reporting system for adverse events following receipt of drugs and immunizations.
- VA Electronic Health Record: a system of electronic health record and administrative data for active surveillance and research.
Tribal nations
- Passive surveillance
- Active surveillance
- IHS Sentinel Survey
- IHS Sentinel Survey