IF YOU ARE FULLY VACCINATED
CDC has updated its guidance for people who are fully vaccinated. See Recommendations for Fully Vaccinated People.
IMPORTANT UPDATE FOR SCHOOLS
CDC recommends schools continue to use the current COVID-19 prevention strategies for the 2020-2021 school year. Learn more
Important update: Healthcare facilities
CDC has updated select ways to operate healthcare systems effectively in response to COVID-19 vaccination. Learn more
UPDATE
Getting vaccinated prevents severe illness, hospitalizations, and death. Unvaccinated people should get vaccinated and continue masking until they are fully vaccinated. With the Delta variant, this is more urgent than ever. CDC has updated guidance for fully vaccinated people based on new evidence on the Delta variant.
UPDATE
Given new evidence on the B.1.617.2 (Delta) variant, CDC has updated the guidance for fully vaccinated people. CDC recommends universal indoor masking for all teachers, staff, students, and visitors to K-12 schools, regardless of vaccination status. Children should return to full-time in-person learning in the fall with layered prevention strategies in place.

Basics of COVID-19

Basics of COVID-19
Updated May 24, 2021
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About COVID-19

COVID-19 is a dangerous disease caused by a virus discovered in December 2019 in Wuhan, China. It is very contagious and has quickly spread around the world.

COVID-19 most often causes respiratory symptoms that can feel much like a cold, a flu, or pneumonia, but COVID-19 can also harm other parts of the body.

  • Most people who catch COVID-19 have mild symptoms, but some people become severely ill.
  • Older adults and people who have certain underlying medical conditions are at increased risk of severe illness from COVID-19.
  • Hundreds of thousands of people have died from COVID-19 in the United States.
  • Vaccines against COVID-19 are safe and effective.

About the name

On February 11, 2020, the World Health Organization announced an official name for the disease: coronavirus disease 2019, abbreviated COVID-19. ‘CO’ stands for ‘corona,’ ‘VI’ for ‘virus,’ and ‘D’ for disease. The virus that causes COVID-19, SARS-CoV-2, is a coronavirus. The word corona means crown and refers to the appearance that coronaviruses get from the spike proteins sticking out of them.

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Other coronaviruses

Coronaviruses are a large family of viruses that can infect people and many animals, including camels, cattle, cats, and bats. There are many types of coronaviruses, including some that give people a common head or chest cold. Other coronavirus diseases like severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS) are extremely dangerous but are much less widespread than colds and COVID-19.