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Good morning, Chicago.

As the coronavirus spreads, new variants continue to develop. The strains that account for the highest number of cases in Illinois are the alpha and delta variants. But now the World Health Organization has added a new variant of interest to its list: Mu.

Meanwhile, the United Center joined a growing list of places with vaccine policies. Venue officials said yesterday that the United Center will require proof of vaccination or a negative COVID-19 test for anyone coming to an event — including Bulls and Blackhawks games this season. Here are the details.

— Nicole Stock, audience editor

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More than 150 undergraduate students at the University of Chicago were diagnosed with COVID-19 in the spring.
More than 150 undergraduate students at the University of Chicago were diagnosed with COVID-19 in the spring.

COVID-19 outbreak at University of Chicago tied to spring break travel by unvaccinated students, new CDC report says

As Labor Day weekend looms for a nation grappling with a more contagious coronavirus variant, public health officials are citing a new report on a post-spring break outbreak among University of Chicago students to discourage travel.

The report, published Thursday by the Centers for Disease Control and Prevention, uses interviews from 140 of the 158 undergraduate students at the Hyde Park campus who were diagnosed with COVID-19 between March 15 and May 3. After spring break, which took place the last week of March, the cases had “increased rapidly” even as the university cracked down via multiple mitigation efforts — including a stay-at-home directive, the report states.

A security guard opens the door to the Whole Women's Health Clinic in Fort Worth, Texas, on Sept. 1, 2021.
A security guard opens the door to the Whole Women’s Health Clinic in Fort Worth, Texas, on Sept. 1, 2021.

Texas abortion law: Here are 4 things to know about how it might impact Illinois

In a 5-4 ruling, the U.S. Supreme Court refused to block a Texas law that bans most abortions as early as about six weeks, before many women even know they’re pregnant. Here are four things to know about the impact the ruling and the law in Texas might have on Illinois.

Editorial: That ‘novel’ Texas abortion legislation is thoroughly un-American

Chicago police headquarters on Oct. 16, 2020.
Chicago police headquarters on Oct. 16, 2020.

Charged Chicago police lieutenant allegedly shoved flashlight between teen’s buttocks during arrest

A veteran Chicago police supervisor is the third city officer this week to be arrested on allegations that he used excessive force in an on-duty incident, authorities said Thursday, accusing him of shoving a flashlight between a clothed teen’s buttocks in February.

Lt. Wilfredo Roman Jr., a Chicago cop since June 2000, was charged with aggravated battery and official misconduct, both felonies.

Volunteer in a Moderna COVID-19 vaccine trial for children under 12 at Lurie Children's Hospital in Chicago, Friday, Aug. 27, 2021.
Volunteer in a Moderna COVID-19 vaccine trial for children under 12 at Lurie Children’s Hospital in Chicago, Friday, Aug. 27, 2021.

Meet some of the kids volunteering in a Chicago COVID-19 vaccine trial: A ‘beacon of hope’ as cases in children surge nationwide

Five dozen volunteers are participating in a Moderna vaccine study underway at Lurie Children’s Hospital, testing the safety and effectiveness of the shot in children ages 6 to 12. While much of the nation is growing impatient for a COVID-19 vaccine for younger kids, medical experts say they must take exceptional care during studies involving children, because their health is paramount.

Jordan Arbus paddles his kayak along the Chicago River on Aug. 31, 2021. He lives in River North and kayaks the Chicago River nearly every day.
Jordan Arbus paddles his kayak along the Chicago River on Aug. 31, 2021. He lives in River North and kayaks the Chicago River nearly every day.

Kayaking the Chicago River this holiday weekend? Now you can get an estimate of bacteria levels before you go.

The Chicago River was once so polluted one swath became known for bubbles that would rise up from the rotting stockyard carcasses below. Today, on sunny afternoons, you can see floating wetlands, beavers and boaters. But after a heavy rain, sewage is still sometimes dumped in the waterway, creating an environment that, for humans, can threaten a bad bout of diarrhea.

This holiday weekend, before you leave to hop in a kayak and paddle up the North Branch, or cruise south toward Bridgeport, you can check what’s in the water. Here’s how.