The first confirmed omicron variant case in suburban Cook County has been reported, health officials announced Wednesday.
The Cook County Department of Public Health announced the variant was identified in a case Tuesday, but did not specify which suburb the variant was found in.
The case, the first known case of omicron in suburban Cook County, was reported in an asymptomatic person who had received at least two doses of the coronavirus vaccine, officials said.
Additional cases could soon be identified as "there are other cases that are currently being genotyped for omicron," the department stated.
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Still, county officials say delta case counts have significantly increased in the days and weeks before the arrival of omicron.
“As expected, omicron has arrived in suburban Cook County and we must take every possible precaution to prevent this highly-contagious variant from spreading rapidly,” Dr. Rachel Rubin, co-lead and senior medical officer for the Cook County Department of Public Health, said in a statement. “Vaccinations, including booster shots, are vital. Masking indoors in all public spaces is mandated in the county and must continue. And we urge unvaccinated residents to not attend any holiday celebrations or social events during this time.”
Health officials in Illinois reported the state's first case of the omicron variant in a Chicago resident last week.
The case was reported in a fully vaccinated city resident who had also received a booster dose but was visited by an out-of-state traveler who also tested positive for the variant. The resident did not require hospitalization, is improving and has been self-isolating since their symptoms began, officials said.
“While unsurprising, this news should remind Chicagoans of the ongoing threat from COVID-19, especially as families prepare to come together over the holidays,” Chicago Department of Public Health Commissioner Dr. Allison Arwady said in a statement. “We know how to slow the spread of this virus: get vaccinated, get boosted, get tested if you have symptoms or have been in contact with someone with COVID-19, and stay away from others if you test positive. Wear a mask indoors, avoid poorly ventilated spaces, practice social distancing, and wash your hands.”
Health officials had been preparing for the variant to be detected in both Chicago and Illinois.
Arwady said at the time that test results were pending for city residents who are known contacts of out-of-state or out-of-country omicron variant cases.
"We are following multiple individuals who we know had exposures, whether they were traveling in the U.S. or even internationally, and we have a pretty robust way to share information in a way to protect privacy, but allow us to do case investigation or contact tracing, including over state boundaries," she said.
So far the variant has already been detected in nearly two dozen U.S. states, with cases also reported in Minnesota and Wisconsin.