CHICAGO (CBS) — Mayor Lori Lightfoot on Sunday defended the decision to hold Lollapalooza given that 90 percent of attendees have been vaccinated against COVID-19, but said gathering on public transit without masks is not acceptable.

At a news conference about the latest uptick in COVID-19 cases fueled by the Delta variant, a reporter pointed out that few Lollapalooza concertgoers have been seen wearing masks in Grant Park. She was asked if she was still confident that going ahead with the festival was not a mistake.

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The mayor noted that the event is outside and 90 percent of those who have gone through the gates are vaccinated. Proof of vaccination or a negative COVID-19 test from within 72 hours have been required for entry.

“We spent a tremendous amount of time working with the Lolla folks to make sure that we incentivize people to get vaccinated,” Mayor Lightfoot said.

She also emphasized that since the city fully reopened in June, millions have attended outdoor events such as baseball games at Wrigley Field and Guaranteed Rate Field and big city festivals, without any resulting surge in COVID cases.

The mayor also said many people got vaccinated for the specific purpose of being able to attend Lollapalooza.

In addition to the vaccination and negative test requirements, festival organizers on Saturday began requiring people to wear masks in indoor spaces. Those include the tents, some of which are enclosed. This came in conjunction with a renewed indoor mask recommendation for the city.

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Meanwhile, scenes on Chicago Transit Authority trains near the festival site have been causing concerns. Photos show packed CTA trains with maskless people coming from the event.

Packed CTA Train After Lollapalooza

(Credit: Mike McDowell)

Mayor Lightfoot said this is not acceptable. While a mask recommendation for public indoor spaces regardless of vaccination status only recently returned for the city of Chicago, mask mandates for public transit under federal guidelines have never gone away.

“Do not get on public transportation in this city without a mask. Do not,” Mayor Lightfoot said, adding that anyone who does so is putting themselves and everyone else at risk.

“I hope that we don’t’ have to get to a point where we’re writing people tickets, but if we need to get to, to get the word out and to make sure that people are complaint, we absolutely will,” the mayor said.

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Sunday is the last day of Lollapalooza.

CBS 2 Chicago Staff