The Illinois Department of Public Health identified 29 individuals who tested positive for COVID-19 or had COVID-19-like symptoms within 14 days after the indoor bar opening event. All 29 cases were confirmed by COVID-19 antigen or nucleic acid amplification tests except for one probable symptomatic case who did not receive testing.
The details were outlined in the CDC's Morbidity and Mortality Weekly Report on Monday, CNN reported. The report did not disclose the name or location of the bar.
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The report did say that bar attendees came in close contact with at least 71 others. Of the 37 close contacts tested for COVID-19, 17 tested positive within 14 days of contact.
Two of the secondary COVID-19 cases were student athletes in close contact of a bar attendee with COVID-19 who attended indoor sports practice and in-person classes. The school, with 650 children, closed for two weeks beginning February 18 after 13 staff members could not work due to isolation, quarantine, or their child in quarantine.
Three of the secondary COVID-19 cases were long-term care facility residents in close contact of a bar attendee who worked as a certified nursing assistant. The nurse tested positive for COVID-19 four days after the bar opening event. One person who contracted one of these secondary COVID-19 cases became hospitalized within 14 days of the positive test result. However, the person was discharged the same day.
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Two weeks after the event, the seven-day average daily COVID-19 incidence in the county more than doubled to at least 86 cases per 100,000 people, according to the report.
"Bars can play a role in community spread of COVID-19 because of limited mask use while eating or drinking and lack of consistent physical distancing," the authors wrote in the report. "These findings show that SARS-CoV-transmission originating in a business such as a bar not only affects the patrons and employees of the bar but can also affect an entire community."
The bar event was held indoors with no outside airflow. Attendees cited inconsistent mask use and disregard of the six feet physical distancing guidelines. Although the total number of people who attended the event is unknown, the bar can accommodate about 100 people, the report said.
The high percentage of symptomatic people linked to the event, 82.6%, as well as the reluctance of many people to disclose contacts suggest that the actual case count was higher than what was found, according to the CDC report.
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"As community businesses begin to reopen, these findings underscore the importance of businesses and individuals adhering to public health prevention and mitigation guidelines to reduce additional community transmission, including isolation after receipt of a COVID-19 diagnosis and while experiencing COVID-19-like symptoms, even as vaccination efforts expand," the authors wrote in the report.
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