The Centers for Disease Control and Prevention have officially confirmed the first case of Covid-19 caused by the Omicron variant in the United States, although the patient, who is fully vaccinated, has reportedly only suffered mild symptoms and is improving.
The case was confirmed by the California and San Francisco Departments of Public Health. The individual had returned from a trip to South Africa on Nov. 22, and the person has been quarantining since testing positive. All of their close contacts have been contacted and tested negative for Covid.
The Omicron variant was named a “variant of concern” by both the World Health Organization and the United States at the end of November, although researchers are still trying to determine the extent of the threat it poses. What is known is that Omicron appears to have at least 50 mutations, including about 30 changes to the spike protein that aids the virus’ ability to enter human cells; this has scientists worried that Omicron could be more contagious and sturdier against immune defenses, including vaccines.
The Omicron variant was discovered in South Africa, although cases have also been detected in nearby Botswana, as well as several European and Asian locations including the U.K., Belgium, Israel, Germany, the Czech Republic, and Hong Kong. The Biden administration recently instituted a travel ban for visitors from eight southern African countries, although similar restrictions were not put in place for visitors to other locales in Europe and Asia where Omicron has been detected.