The CDC has been working with global public health partners and industry to learn about Omicron, as we continue to monitor its course. We are still learning about how easily it spreads, the severity of the disease it causes, and how vaccines available and medications work against it.
The spread
Omicron variants are more easily spread than the original virus that causes COVID-19 and Delta variants. The CDC expects that anyone infected with Omicron can spread the virus to others, whether they are vaccinated or have no symptoms.
Symptoms
People infected with the Omicron variant may have the same symptoms as before. The presence and severity of symptoms may be affected by the status of the COVID-19 vaccine, the presence of other health conditions, age, and history of previous infections.
Serious Illness
Omicron infections often cause a much worse disease than previous infections. Preliminary data suggest that Omicron may cause a more mild form of the disease, although some people may have a more serious illness, require hospitalization, and may die from infection in this different way. Even if only a small percentage of people with Omicron infection need to be hospitalized, a large number of cases may exceed the health care system which is why it is important to take precautionary measures.
Terms
The COVID-19 vaccine remains the best public health measure to protect people from COVID-19 and to reduce the chances of developing new strains. This includes the main series, inspiring shorts, and additional doses for those who need them.
Scientists are still learning how the COVID-19 vaccine works in preventing infections from Omicron. Current vaccines are expected to protect against serious illness, hospitalization, and death due to a separate Omicron infection. However, successful infections in vaccinated people are more likely to occur. People who have the latest information on their COVID-19 vaccine and who receive COVID-19 are less likely to develop the
serious illness than those who are not vaccinated and receive COVID-19.
Treatment
Scientists are working to find out how effective the current treatment of COVID-19 is. Some, but not all, monoclonal antibody treatments are still effective against Omicron. Public health facilities work with health care providers to ensure that effective treatment is used effectively to treat patients.