The United States has confirmed its first case of the new, heavily mutated coronavirus variant called omicron in Northern California.

Iran PressAmerica: The US health officials have confirmed the country’s first case of the new, heavily mutated coronavirus variant called omicron in California, the Centers for Disease Control and Prevention said Wednesday.

White House chief medical advisor Dr. Anthony Fauci said the individual, who was fully vaccinated, had just returned from traveling in South Africa to the San Francisco area on Nov. 22 and tested positive on Nov. 29.

The omicron variant has a high number of mutations that suggest it may spread just as or more easily than the delta variant, which accounts for 99.9 percent of Covid cases in the US.

Scientists have cautioned that it's still unclear whether omicron is more dangerous than other versions of the virus that has killed more than 5 million people worldwide. It is also unknown how well the vaccines and treatments would work against the variant.