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CHICAGO — Lollapalooza officials announced masks will be required by all patrons in any indoor spaces at Grant Park beginning Saturday, based on advice from the Chicago Department of Public Health.

The requirement is in place for all attendees regardless of vaccination status, and the festival will continue to require vaccination cards or proof of a negative COVID-19 test for admission each day.

The announcement comes as state and local health officials are grappling with a rapid rise of COVID-19 cases, many of which can be attributed to the more contagious Delta variant.

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Illinois has reported over 11,600 new COVID-19 cases over the last 7 days, although COVID-19 patients comprise just 4 percent of total hospitalizations and 7 percent of ICU beds.

The CDC recently revised its mask guidelines after evidence showing that vaccinated individuals can transmit the virus to others.