Questions about safety & effectiveness

The COVID-19 vaccine will be released only when it’s proven safe and effective.

To date, the vaccines in trial have been tested on tens of thousands of people and have passed safety requirements in Phase I and Phase II trials. As an additional layer of checks and balances, an external advisory board of medical and research professionals using additional public health data will review final COVID-19 vaccine data.

Clinical trials are an important part of determining vaccine safety and effectiveness. Currently, phase 3 clinical trials are underway for 4 vaccines involving thousands of participants. The purpose of clinical trials is to generate scientific data and other information for the Food and Drug Administration to review and base their recommendations on.

Vaccine safety monitoring systems are in place to collect side effect data. If an unexpected adverse event is seen, experts quickly study it further to assess whether it is a true safety concern that warrants changes in U.S. vaccine recommendations. This monitoring is critical to help ensure that the benefits continue to outweigh the risks for people who receive vaccines.

America’s best medical and research professionals have been working for years on coronavirus vaccines for SARS and MERS. While SARS and MERS are different than COVID-19, they belong to the coronavirus family. The lessons learned through those developments are being applied today. 

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1. Questions about safety & effectiveness
2. How did a vaccine happen so quickly?
3. Can the COVID-19 vaccine make you sick?
4. I received a flu vaccine, so why would I need the COVID-19 vaccine?
5. Concerns about DNA altering
6. Who should receive the COVID-19 vaccine?
7. Concerns about the ingredients used in the COVID-19 vaccines
8. What are the possible side effects of a COVID-19 vaccine?
9. I've been vaccinated. Should I continue to wear a mask, social distance and avoid large gatherings?
10. Why do I need a vaccine when most people recover from COVID-19?
11. If I've recovered from COVID-19, do I still need to get vaccinated?
12. Will vaccines be mandated?