CHICAGO (CBS) — Facing a resurgence of COVID-19 cases fueled by the more contagious delta variant’s spread among the unvaccinated, Chicago once again will be requiring people to wear masks while indoors in public settings, effective Friday.

The new indoor mask mandate will go into effect on Friday for anyone age 2 or older, regardless of their vaccination status, and covers all businesses in Chicago; including bars and restaurants, gyms, common areas of condos and multi-residential buildings, and private clubs.

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Chicago Department of Public Health Commissioner Allison Arwady announced the new mask mandate Tuesday afternoon, and said the city doesn’t expect any additional COVID-19 restrictions, such as capacity limits or orders for bars, restaurants, gyms and other businesses to require indoor customers to show proof of vaccination.

“We’re hopeful that having the masks in place for everybody will get us through delta, while we keep working on getting folks vaccinated, and with doing that our goal is to remain open, but careful,” she said.

Customers will be allowed to remove masks at restaurants, bars, and other eating establishments while they are eating or drinking.

Chicago Department of Business Affairs and Consumer Protection Acting Commissioner Ken Meyer said customers at other businesses can also take off their masks for other activities that require their removal, such as beard trims and facials. In addition, employees who work in settings that are not open to the public may remove their masks if they can maintain at least six feet of social distancing.

“Businesses have stepped up in the past to keep our city safe, and we must do it again, what is necessary to save lives,” Meyer said.

Masks will continue to be optional outdoors, where the risk of spreading COVID-19 remains lower.

The return the return of the indoor mask mandate comes as Chicago has surpassed an average of 400 new cases of COVID-19 per day, largely among the unvaccinated, and caused mostly by the more contagious delta variant.

Chicago is averaging 419 new cases of COVID-19 per day over the past week, up from the rate’s lowest point of less than 40 per day in mid-June.

Arwady said 99.7% of Chicagoans who have been fully vaccinated have not been diagnosed with COVID after getting their shots, and 99.99% of Chicagoans who have been fully vaccinated have not been hospitalized or died after getting their shot.

More than 95% of all new confirmed cases in COVID-19 in Chicago are the delta variant, according to Arwady. She said that’s because it is so much more contagious than other variants of the virus.

“If you’ve been waiting to get your vaccine, especially if you’re over 60, delta is here. Now is the time,” she said. “Getting people who are unvaccinated started on vaccine is the most important thing to protect everybody.”

Arwady said the new indoor mask mandate will remain in place as long as the city is averaging more than 400 new COVID-19 cases per day.

“Once we get through the delta surge, I anticipate that will come back down. When we move consistently under 400 cases per day, it will revert to a mask recommendation,” she said.

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When the city’s daily case load drops below 200 cases per day, Arwady said that mask recommendation would be lifted as well.

The new mask mandate does not include any new capacity restrictions for Chicago businesses. However, if the city’s average daily case count rises above 800 cases per day, or if the city’s hospitalization numbers “move in ways that look untenable,” Arwady said the city might be forced to institute further COVID-19 restrictions.

Arwady said she remains confident that there is no connection between the latest surge in COVID cases and the city’s decision to allow Lollapalooza to go forward at the end of July, with an estimated 100,000 people attending each day of the festival in Grant Park.

“We’ve not had new data suggesting it was a super-spreader,” Arwady said. “Our highest ase rates actually are in people in their 30s and 40s, not the demographic, really, at Lollapalooza.”

The latest update to the city’s masking rules goes even further than CDC’s recommendation that people wear masks indoors in areas with substantial or high transmission of COVID-19.

According to the CDC, areas with substantial spread are those with 50 to 99 cases per 100,000 people over a seven-day period, and areas with high transmission are those with more than 100 cases per 100,000. Chicago is currently in the high transmission category, as is the vast majority of Illinois. Only one county in Illinois – Stark County – is seeing moderate transmission, three counties are seeing substantial spread, and the rest are in the high transmission category.

The new mask requirement in Chicago comes three months after the city lifted its indoor mask mandate for fully vaccinated people in most settings in May, leaving in place a requirement for those who weren’t fully vaccinated to continue wearing masks indoors. In June, the city lifted all of its mask requirements when it fully reopened for the first time since the pandemic started.

However, businesses have been allowed to set their own rules regarding masks and social distancing, and the U.S. Centers for Disease Control and Prevention still requires masks on public transportation and in airports.

Earlier this month, Gov. JB Pritzker announced a mask mandate for all Illinois schools, both public and private.

Meantime, the city added eight more states and Washington, D.C., to its travel advisory, recommending people from those states quarantine upon arrival, or show proof they recently tested negative for COVID-19.

The new states include  Minnesota, New Jersey, North Dakota, Pennsylvania, Rhode Island, Utah, Virginia, West Virginia.

The travel advisory now covers 39 states, as well as D.C., Puerto Rico and the U.S. Virgin Islands.

Unvaccinated visitors from states and territories on the city’s travel advisory are urged to either obtain a negative COVID-19 test result no more than 72 hours before arriving in Chicago, or quarantine for a 10-day period upon arrival.

Anyone who has been fully vaccinated is exempt from the travel advisory.

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According to the city, returning Chicago residents and out-of-state visitors coming to Chicago are urged to get vaccinated and abide by all remaining federal, state, and local safety measures.

  • Adhere to masking rules: Masks are required on planes, buses, trains, and other forms of public transportation traveling into, within, or out of the United States and in U.S. transportation hubs such as airports and stations.
  • It is recommended that you bring a copy of your COVID-19 vaccination records while traveling.

CBS 2 Chicago Staff