More Chicagoans are being vaccinated every day, and it comes at a crucial time. The positivity rate is on the rise: it’s currently at 4.5%, up from 3.3% last week. The daily case average is also up to 498 compared to 363 cases last week.

Dr. Allison Arwady, the commissioner of the Chicago Department of Public Health, said the latest surge in COVID-19 cases is being heavily driven by younger Chicagoans—18-29 years old leading. She said the city is also seeing more cases among white Chicagoans and those who live on the North Side.

Some experts say that restaurant diners and bar patrons have contributed to the surge in cases.

The Centers for Disease Control and Prevention found similar results in a study earlier this month that easing restrictions on indoor dining in restaurants can increase cases and deaths.

Mayor Lori Lightfoot said earlier this week the increase is due in part to how people are acting at bars and restaurants, not that businesses are open.

“It’s not the playing the sports or being at bars that is causing these outbreaks—it’s the risky behavior in those settings that’s creating the problem,” Lightfoot said. “Not wearing a mask, not social distancing. We’ve got to get back to what we know saves us, saves our families, saves people in our network and our community.”

Arwady said she hopes the city won’t have to go back to restrictions on dining and drinking since the city already has strict requirements for dining.

“My goal is not to have to go back at all, but we’re also not at a point where we can further loosen anything, particularly on the indoor side at this time,” Arwady said.