First case of omicron variant reaches the United States

In a White House press briefing on Wednesday, Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, confirmed that the United States’ first case of the omicron coronavirus variant was detected in California.

The infected individual travelled from South Africa on Nov. 22, tested positive for COVID-19 on Nov. 29, and is currently self-quarantining, Fauci told reporters.

So far, the individual’s close contacts have tested negative for the coronavirus.

The infected person was fully vaccinated – but had not yet received a booster shot –  and is experiencing "mild symptoms, which are improving at this point," Fauci added.

The California and San Francisco public health departments were able to confirm that the nation’s first reported case was caused by the omicron variant through genomic sequencing conducted at the University of California at San Francisco. The CDC subsequently confirmed the sequence, CNN reported.

On Monday, President Biden reassured Americans saying the variant is "a cause for concern, not a cause for panic," adding "we'll have to face this new threat just as we face those who have come before it."

While little is yet known about the new variant, scientists around the globe are rushing to determine if omicron – which has significant mutations compared to previous strains – is more infectious, deadly or able to evade vaccines.

The delta variant of the coronavirus remains the dominant variant in the United States and around the globe.

Cases in the Americas have also been reported in Canada and Latin America.