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CDC - Vaccines Work

COVID-19 Vaccines Work Research studies show that the COVID-19 vaccines currently authorized and recommended for use in the United States work well at preventing COVID-19. • COVID-19 vaccines help protect people who are vaccinated from getting sick or severely ill with COVID-19. • COVID-19 vaccines can reduce the risk of people spreading COVID-19. • COVID-19 vaccination is an important tool to help stop the pandemic. • CDC recommends that you get a COVID-19 vaccine as soon as you can. Vaccines used in the United States are tested by the U.S. Food and Drug Administration, or FDA, before they are authorized for use. Once the vaccines are in use, scientists and health experts continue to research and evaluate how the vaccines work in real-world conditions. So far, research is showing that Pfizer-BioNTech and Moderna COVID-19 vaccines provide similar protection in real-world conditions as they showed in the clinical trial testing. The Pfizer-BioNTech vaccine has been shown to be 95% effective at preventing COVID-19 after receiving both doses. The Moderna vaccine has been shown to be 94.1% effective at preventing COVID-19 in people who received 2 doses. Johnson & Johnson’s Janssen vaccine has been shown to be 66.3% effective at preventing COVID-19. Results from real-world data show that one dose of either of Pfizer-BioNTech or Moderna vaccines provides some protection against COVID-19. However, to receive the most protection, people should receive both recommended doses of the Pfizer-BioNTech or Moderna COVID-19 vaccine. Johnson & Johnson’s Janssen vaccine requires only 1 dose. Regardless of which vaccine you receive, it typically takes about 2 weeks for the body to build protection after you get your vaccination. That means it is possible you could still get COVID-19 soon after getting vaccinated. This is because your body has not had enough time to build protection. Protect yourself until you are fully vaccinated. During this time, it is very important to keep using the recommended public health practices to protect yourself and others from the virus and variants of the virus. Make sure that you: • Wear a mask that covers your nose and mouth. • Stay at least 6 feet apart from others who don’t live with you. • Avoid crowds and poorly ventilated indoor spaces. • And wash your hands often with soap and water. Use hand sanitizer if soap and water aren’t available. Although the vaccines are effective, they are not 100% effective. This means some people who are fully vaccinated against COVID-19 will still get sick. COVID-19 variants Since variants of the virus are now spreading in the United States, there is research going on to test how effective the current COVID-19 vaccines are against the variants. Current information shows that COVID-19 vaccines used in the United States provide protection against most variants. This is another reason why COVID-19 vaccination is an important tool to help protect people against COVID-19, including protecting against the new variants. CDC recommends you get vaccinated as soon as you can. • If you are fully vaccinated, you can resume activities that you did before the pandemic. • Fully vaccinated people can resume activities without wearing a mask or physically distancing, except where required by federal, state, local, tribal, or territorial laws, rules, and regulations, including local business and workplace guidance. • If you haven’t been vaccinated yet, find a vaccine. For more ASL videos on COVID-19, including information on Vaccines and Vaccine Safety, COVID-19 Variants, and How to Talk to Your Family and Friends About the COVID-19 Vaccines, go to the CDC YouTube channel. For more information in English text, please visit