(WTTW News)

The omicron variant of COVID-19, which is believed to be highly transmissible, has been detected in Chicago, state and city health officials announced Tuesday. 

The first case of the omicron variant was discovered in a Chicagoan who was a “known contact of a confirmed Omicron case from another state who visited Chicago,” according to a statement from Chicago and Illinois health officials. 

“The Chicago resident — fully vaccinated with a booster dose — did not require hospitalization, is improving and has been self-isolating since their symptoms began,” according to the statement. 

Mayor Lori Lightfoot and Gov. J.B. Pritzker urged all Illinois residents older than 5 to get vaccinated, and for those older than 18 to get a booster dose of the vaccine as soon as they are eligible. Everyone should also wear a mask while indoors in a public space, according to state rules. 

The state’s first case was identified by a lab at Rush Hospital, which examines COVID-19 cases through a partnership with the Chicago Department of Public Health. 

“While unsurprising, this news should remind Chicagoans of the ongoing threat from COVID-19, especially as families prepare to come together over the holidays,” said Chicago Department of Public Health Commissioner Dr. Allison Arwady. 

Even before the detection of the omicron variant of COVID-19, Chicago is now experiencing a second wave of cases of the delta variant of COVID-19.  

Arwady called the surge “very significant” in an online question-and-answer session Tuesday morning. 

There is now a “very high risk” of COVID-19 transmission in Chicago, according to the Chicago Department of Public Health because the city averaged 828 confirmed cases of COVID-19 during the past week. 

Contact Heather Cherone: @HeatherCherone | (773) 569-1863 | [email protected]