How do we know the COVID-19 vaccine is safe?
The U.S. vaccine safety system ensures that all vaccines are as safe as possible. Safety is a top priority while federal partners work to make a COVID-19 vaccine(s) available. Vaccines undergo a series of rigorous clinical trials using thousands of study participants to generate data and other information for the Food and Drug Administration (FDA) to determine their safety and effectiveness to approve or authorize for emergency use. Following approval or authorization, many vaccine safety monitoring systems watch for adverse events or possible side effects. Visit the CDC’s website for more information about ensuring the safety of COVID-19 vaccines in the U.S.—including information about specific vaccine monitoring systems.