United Center mass vaccination site set to open March 10 Mar 1, 2021 | coronavirus, Top Stories, Vaccination A mass vaccination site at Chicago’s United Center capable of administering 6,000 doses per day will open on March 10, officials announced last week.To access this content, you must purchase 1 Year Health News Illinois Subscription or 1 Year Group Subscription - Up to 5 Users, or log in if you are a member.