Omicron – B.1.1.529, BA.1, BA.1.1, BA.2, BA.3, BA.4 and BA.5
First identified: South Africa
Spread: Spreads more easily than other variants. CDC is working with state and local public health officials to monitor the spread of Omicron.
Symptoms: Please refer to Symptoms of COVID-19 | CDC
Severe illness and death: Data suggest that Omicron is less severe in general. However, a surge in cases may lead to significant increases in hospitalization and death. More data are needed to fully understand the severity of illness and death associated with this variant.
Vaccine: Breakthrough infections in people who are vaccinated are expected, but being up to date on recommended vaccines is effective at preventing severe illness, hospitalizations, and death. The emergence of the Omicron variant further emphasizes the importance of vaccination and boosters.
Treatments: Some, but not all, monoclonal antibody treatments remain effective against Omicron. Public health agencies work with healthcare providers to ensure that effective treatments are used appropriately to treat patients.
Learn more about the Omicron variant