A Barcelona COVID-19 experiment held last month has concluded that the use of antigen tests is an efficient strategy to enable the holding of concerts as none of the nearly 500 attendees at the event were infected.

More than 1,000 music fans took part in the scientific study on December 12 to test the effectiveness of same-day COVID-19 screening in order to safely hold concerts and events without social distancing.

The study, which has been organised by Barcelona’s The Fight AIDS and Infectious Diseases Foundation along with the Primavera Sound music festival, randomly selected half of the volunteers to take part in the free concert at the city’s Sala Apolo venue, while the other 500 were sent home as a control group.

Organisers used this group to analyse if there was any contagion inside the concert hall despite the screening with antigen tests, which while not as accurate as other types of tests, do produce results in 15 minutes as compared to several hours, or days, later.

“The results are conclusive and allow us to affirm that, if a study is reproduced with the same conditions, the results would always be the same. It is safe to carry out this type of activities and concerts,” said Dr Josep Maria Llibre, one of those responsible for the study.

One of the primary organisers of the research project added on Twitter: “Only two participants in the control group, who did not enter the venue, became infected. This study demonstrates that a live music concert performed under a series of safety measures that include a SARS-CoV-2 negative antigen test is not associated with an increase in infections due to #COVID19.”

The 500 allowed into the five-hour music festival of rock groups and DJs had to wear FFP2 face masks and use hand disinfectant. However, they were not required to remain socially distanced on the concert floor.

The face masks were required except in the upstairs bar where organisers allowed them to be removed to have the one drink volunteers were treated to.

The 1,000 volunteers had two PCR tests, which have a higher capacity to detect the virus than the same-day antigen test, first on the Saturday before the concert, and then again eight days later. These PCR tests allowed researchers to determine if any infected people got past the same-day antigen screen and, if so, did they infect others inside the show.

Organisers said in a release: “Attendance at a live music concert performed under a series of security measures that included a negative antigen test for SARS-CoV-2 performed on the same day, was not associated with an increase in COVID infections.”

Boris Revollo, a co-lead of the study in Spain, said the “list of conditions included in the present study are easily reproducible and could be escalated to other events.”

Concert halls have been one of the hardest hit sectors by the health restrictions applied in Spain, twice being completely shut down for several months. In November, an association representing concert halls in Spain said that more than 25,000 shows had been cancelled because of the pandemic, costing the industry €120m in lost revenue. Halls were only recently allowed to reopen in Barcelona but at 50 per cent capacity or a maximum of 500 people.

The 2021 edition of Primavera Sound Barcelona is scheduled to take place on June 2 to 6 after this year’s edition was cancelled due to the virus.