First Omicron Variant Case Identified in US

Damian McNamara

December 01, 2021

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The first case of the Omicron variant of the coronavirus in the United States was confirmed by officials today in an individual in California who had recently traveled to South Africa. He or she was fully vaccinated against COVID-19 and experienced only "mild symptoms that are improving," officials with the CDC said. 

The patient, who was not named in the CDC's annoucement of the first U.S. case of the Omicron variant on Wednesday, is self-quarantining.

"All close contacts have been contacted and have tested negative," officials said. 

The announcement comes as no surprise to many as the Omicron variant, first identified in South Africa, has been reported in countries around the world in recent days. Hong Kong, the United Kingdom, and Germany each reported this variant, as have Italy and the Netherlands. Over the weekend, the first North American cases were identified in Canada.

Anthony Fauci, MD, director of the National Institute of Allergy and Infectious Diseases, announced over the weekend that this newest variant was likely already in the U.S., telling ABC's This Week its appearance here was “inevitable.”

Similar to previous variants, this new strain likely started circulating in the U.S. before scientists could do genetic tests to confirm its presence.

The World Health Organization named Omicron a "variant of concern" on Friday, even though much remains unknown about how well it spreads, how severe it can be, and how it may resist vaccines. In the meantime, the U.S. enacted travel bans from multiple South African countries.

It remains to be seen if Omicron will follow the pattern of the Delta variant, which was first identified in the U.S. in May and became the dominant strain by July. It's also possible it will follow the path taken by the Mu variant. Mu emerged in March and April to much concern, only to fizzle out by September because it was unable to compete with the Delta variant.

Damian McNamara is a staff journalist based in Miami. He covers a wide range of medical specialties, including infectious diseases, gastroenterology, and critical care. Follow Damian on Twitter:  @MedReporter.


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