Editor’s Note: Find the latest COVID-19 news and advice in the Medscape Coronavirus Resource Center.
Spanish researchers shared the encouraging results of the first randomized controlled trial to assess the risk of transmission of COVID-19 during a live music concert in a hall.
The study, published on May 27 in The Lancet Infectious Diseases, led by virologist Boris Revollo, MD, of Germans Trias i Pujol University Hospital in Barcelona, Spain, included comprehensive safety measures.
It was conducted on December 12, 2020, at a time when local travel restrictions were in place, room meetings were limited to six people, and vaccines were not yet available..
All 465 attendees at the event were screened for SARS-CoV-2 the same day with rapid diagnostic tests for antigens before they entered, wore masks everywhere and followed crowd control measures in the venue well ventilated, which can hold up to 900 people.
The control group consisted of 495 participants randomly assigned to go home instead of attending the concert after the screening..
None of the participants tested positive for SARS-CoV-2 infection by polymerase chain reaction (PCR) test 8 days after the 5-hour event, although two in the control group did. have done.
In fact, the study showed that the risk of infection was no greater in those who attended the concert than in those who lived in the same community and did not attend.
The Bayesian estimate of the incidence between the test and control groups was –0.15% (95% confidence interval, –0.72 to 0.44).
“Our results pave the way for the reactivation of cultural activities interrupted during COVID-19, which could have important socio-cultural and economic implications,” write the authors.
All wore masks everywhere
As part of comprehensive safety measures, in addition to testing, all participants had their temperature checked before entering and were given an N95 face mask, which had to be worn inside at all times.
Hand sanitizer was provided in several locations, access doors were left open to allow fresh air to circulate, and the locker room was closed to prevent clustering.
There was no mandatory distancing, people could sing and dance, and alcohol was available at a bar located in a separate room from the concert, and drinks were only allowed in that space.
Rosanna W Peeling, PhD, professor and chair of diagnostic research at the London School of Hygiene and Tropical Medicine in the UK, and David L. Heymann, MD, of the Department of Infectious Disease Epidemiology, said in a commentary from accompaniment that there was a great need for studies like this to help establish evidence of a return to normal gatherings.
“So many countries have no policy or no way to do it because they don’t have evidence,” Peeling said. Medscape Medical News.
The study was conducted well and a strength was the test 8 days later, which can be difficult to do for similar events when people disperse to places outside the community where the event or gathering. took place, she said.
The study invites further questions
Peeling and Heymann also write that the work raises questions such as whether three-layer masks would have been sufficient. Or how does rapid antigen testing on entry compare to molecular testing within 72 hours of entry?
They noted that there are also questions about whether existing rapid diagnostic tests are able to detect variants of COVID-19.
Peeling said these kinds of results need to be shared and shared more quickly, “if we are ever to get out of this pandemic.”
Studies like this are also difficult, she noted, as they can involve entities unrelated to the health sector such as city governments and concert organizers working with researchers.
In addition, security measures come at a considerable cost and it is not clear whether they could be used regularly during such events.
“It’s not really sustainable at sporting events with 20,000 people,” Peeling said.
Infectious disease expert William Schaffner, MD, of Vanderbilt University School of Medicine in Nashville, Tennessee, said Medscape Medical News that the results of the study “come a little late to the party”.
If this study had been done in today’s era with licensed vaccines, “it would have been a questionable problem,” he said. “The mask is a barrier to transmission, but now we have a much stronger barrier than we could put in place, which is vaccination.
“Having said that, it does reinforce the fact that wearing a classic mask really does offer protection even in a crowded place,” Schaffner said.
He added that the study was relatively small and that he would like to see it replicated in concerts or larger group gatherings.
Peeling and Heymann do not report any relevant financial relationship. A co-author is an employee and shareholder of Primavera Sound, sponsor of the study. All other authors do not declare any relevant financial relationship.
The work was financed by Primavera Sound Group and the #YoMeCoronoInitiative.
Marcia Frellick is a freelance journalist based in Chicago. She has already written for the Chicago Tribune, Scientific news, and Nurse.com, and was an editor at Chicago Sun-Times, the Cincinnati Applicant, and the St. Cloud (Minnesota) schedules. Follow her on Twitter at @mfrellick.
For more news, follow Medscape on Facebook, Twitter, Instagram, YouTube and LinkedIn.