COVID-19 risk mitigation in reopening mass cultural events: population-based observational study for the UK Events Research Programme in Liverpool City Region.
Burnside G., Cheyne CP., Leeming G., Humann M., Darby A., Green MA., Crozier A., Maskell S., O'Halloran K., Musi E., Carmi E., Khan N., Fisher D., Corcoran R., Dunning J., Edmunds WJ., Tharmaratnam K., Hughes DM., Malki-Epshtein L., Cook M., Roberts BM., Gallagher E., Howell K., Chand M., Kemp R., Boulter M., Fowler T., Semple MG., Coffey E., Ashton M., COVID-19 Genomics UK (COG-UK) Consortium None., García-Fiñana M., Buchan IE.
ObjectivesTo understand severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission risks, perceived risks and the feasibility of risk mitigations from experimental mass cultural events before coronavirus disease 2019 (COVID-19) restrictions were lifted.DesignProspective, population-wide observational study.SettingFour events (two nightclubs, an outdoor music festival and a business conference) open to Liverpool City Region UK residents, requiring a negative lateral flow test (LFT) within the 36 h before the event, but not requiring social distancing or face-coverings.ParticipantsA total of 12,256 individuals attending one or more events between 28 April and 2 May 2021.Main outcome measuresSARS-CoV-2 infections detected using audience self-swabbed (5-7 days post-event) polymerase chain reaction (PCR) tests, with viral genomic analysis of cases, plus linked National Health Service COVID-19 testing data. Audience experiences were gathered via questionnaires, focus groups and social media. Indoor CO2 concentrations were monitored.ResultsA total of 12 PCR-positive cases (likely 4 index, 8 primary or secondary), 10 from the nightclubs. Two further cases had positive LFTs but no PCR. A total of 11,896 (97.1%) participants with scanned tickets were matched to a negative pre-event LFT: 4972 (40.6%) returned a PCR within a week. CO2 concentrations showed areas for improving ventilation at the nightclubs. Population infection rates were low, yet with a concurrent outbreak of >50 linked cases around a local swimming pool without equivalent risk mitigations. Audience anxiety was low and enjoyment high.ConclusionsWe observed minor SARS-CoV-2 transmission and low perceived risks around events when prevalence was low and risk mitigations prominent. Partnership between audiences, event organisers and public health services, supported by information systems with real-time linked data, can improve health security for mass cultural events.