U.S. Records Its First Case of the Omicron Variant in California, CDC Confirms

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The United States has recorded its first case of the Omicron variant, according to the Centers for Disease Control and Prevention.

The CDC confirmed the case in California in a statement released Wednesday. The agency says the infected individual, who is fully vaccinated, returned from South Africa on Nov. 22.

The traveler is experiencing "mild symptoms" and is "improving," per the CDC. So far, all close contacts have tested negative for COVID-19.

The Omicron variant was first identified in Botswana by researchers in South Africa. The World Health Organization panel labeled the new variant as "highly transmissible" at a meeting on Friday.

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The CDC says it "has been actively monitoring and preparing for this variant," and will continue to "work diligently" to learn more about it.

The agency also reiterated the importance of being vaccinated against COVID-19. All individuals age 18 and over are now eligible to receive a booster.

Staff are seen preparing Pfizer vaccine doses inside the Melbourne Showgrounds COVID-19 Vaccination Centre on July 20, 2021 in Melbourne, Australia
Staff are seen preparing Pfizer vaccine doses inside the Melbourne Showgrounds COVID-19 Vaccination Centre on July 20, 2021 in Melbourne, Australia

Daniel Pockett/Getty

"The recent emergence of the Omicron variant (B.1.1.529) further emphasizes the importance of vaccination, boosters, and general prevention strategies needed to protect against COVID-19," the CDC said in Wednesday's statement.

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On Sunday, Canadian health officials confirmed the first two cases of the variant in North America. Two individuals that had recently returned from a trip to Nigeria were found to have contracted the strain.

Two days later, the CDC labeled Omicron a "variant of concern."

"This decision is based on multiple factors," the agency said on their website, "including the detection of Omicron cases in multiple countries, transmission and displacement of Delta in South Africa, and mutations in the virus that could indicate a reduction in the effectiveness of COVID-19 vaccines and certain monoclonal antibody treatments.

RELATED: CDC 'Strongly Encourages' COVID Vaccine Boosters for All Americans Due to Omicron Variant

The Omicron variant has now been found in at least 25 countries, including the U.S. Travelers from Australia, Austria, Belgium, Britain, Canada, Czech Republic, Denmark, Germany, Israel, Italy, the Netherlands, Portugal, Spain and Hong Kong have also contracted the strain.

On Monday, President Joe Biden said the variant is a "cause for concern," but emphasized that it's "not a cause for panic."

"We have the best vaccine in the world, the best medicines, the best scientists, and we're learning more every single day," said Biden, 79. "We'll fight this variant with scientific and knowledgeable actions and speed, not chaos and confusion."

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