This story was updated at 6:29 p.m. on Thursday, Dec. 16, 2021 with more information.
The omicron variant of the coronavirus has been reported in Hamilton County, health department officials confirmed Thursday, though it's likely been spreading undetected locally for several days, if not weeks, due to limited testing.
Omicron was named a "variant of concern" by the World Health Organization on Nov. 26 due to its significant number of mutations on the virus's signature "spike protein" and a dramatic spike in COVID-19 cases in South Africa, where the variant was first identified.
South Africa and the United Kingdom both reported a record number of coronavirus cases this week amid respective omicron waves, according to The Washington Post.
It's unknown if omicron infections cause more severe illness or death than previous viral variants, and although the delta variant remains the dominant strain in the United States, omicron cases are rising rapidly and expected to overtake delta as the predominant variant.
"Omicron is spreading at a rate we have not seen with any previous variant," Tedros Adhanom Ghebreyesus, director of the World Health Organization, said during a news briefing this week. "We're concerned that people are dismissing omicron as mild ... Even if omicron does cause less severe disease, the sheer number of cases could once again overwhelm unprepared health systems."
Public health officials in the United States are now projecting a winter COVID-19 wave fueled by holiday travel, gatherings and omicron, which is likely to further strain health systems still grappling with the effects of the delta variant.
New COVID-19 cases have been on the rise in Hamilton County since Thanksgiving, with an average of 106 new cases reported each day over the past week compared to an average of 41 new cases per day the week leading up to Nov. 25.
The spike in new cases is a sign of uncontrolled community spread, and the rise of at-home testing means many positive cases are likely going unreported.
Over the past week, an average of 71 COVID-19 patients were being treated in Hamilton County hospitals — a far cry from the pre-delta low point of nine patients in late June.
Hamilton County Health Department officials said in an email that "omicron's arrival is something entirely expected and was eventually going to happen."
Early data indicates people who are fully vaccinated and boosted continue to have good protection against severe COVID-19 illness and death with omicron.
"The most important thing you can do to protect yourself against omicron is to get your vaccine. If you have received your primary series already, then please get boosted," health department officials said.
The health department is also still distributing free, at-home COVID-19 test kits from 9 a.m.-3 p.m., Monday through Friday at its main facility on East Third Street, while supplies last.
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