Important update: Healthcare facilities
CDC has updated select ways to operate healthcare systems effectively in response to COVID-19 vaccination. Learn more
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.
UPDATE
The White House announced that vaccines will be required for international travelers coming into the United States, with an effective date of November 8, 2021. For purposes of entry into the United States, vaccines accepted will include FDA approved or authorized and WHO Emergency Use Listing vaccines. More information is available here.
UPDATE
Travel requirements to enter the United States are changing, starting November 8, 2021. More information is available here.

Variants and Genomic Surveillance for SARS-CoV-2

Variants and Genomic Surveillance for SARS-CoV-2
Updated Apr. 2, 2021
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Omicron Spread

CDC is monitoring the current surge of COVID-19 cases. Learn more about the Omicron variant and its expected impact on hospitalizations.

About Omicron
Hospitalization Forecast

female lab technician doing research with a microscope in the lab - coronavirus
Genomic Surveillance
Data & Sequencing
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About Variants
Viruses are constantly changing, including the virus that causes COVID-19. These changes occur over time and can lead to the emergence of variants that may have new characteristics. Vaccines continue to reduce a person's risk of contracting the virus that cause COVID-19. Vaccines are highly effective against severe illness.
Research and Selected Publications