Researchers in Germany have held a pop concert for 1,500 people to see how those attending would spread coronavirus.
The experiment held by the University Hospital in Halle packed part of a Leipzig arena with volunteers, collecting data in a "real life" simulation of a pop concert with strict health and safety controls.
Each participant took a coronavirus test ahead of time and once they tested negative, they had to wear protective masks throughout the testing.
Researchers equipped each volunteer with contact tracers to record their routes in the arena and track the path of the aerosols - the small particles that could carry the virus - they emitted as they mingled and talked.
Fluorescent disinfectants were used to highlight which surfaces at the mock concert were touched most frequently.
German pop singer Tim Bendzko appeared on stage to create a realistic reaction from the crowd for the experiment's three different scenarios.
Afterwards, he said he had expected the day to feel more sterile, but that the crowd "had a lot of fun".
“We really had a lot of fun,” he said. “We survived drive-in concerts this summer and in that respect, for us, this is a first step towards normality.”
In the first scenario, which simulated the very beginning of a pandemic, the concertgoers were kept close together in the room with no social distancing.
In the second, the researchers introduced hygiene measures and larger social distances between the volunteers.
In the third, a distance of 1.5 metres between participants was strictly enforced.
Stefan Moritz, who led the study, said researchers had only about a third of the volunteers they had hoped for, partly because many Germans are still away on summer holidays and partly due to fears of participating.
But he said the experiment had gone well.
"We are satisfied with the numbers," he told reporters. "We have good data quality."
The results of the study are expected in four to six weeks, he said.
Germany has registered only 9,267 confirmed virus deaths so far, one-fourth of Britain’s virus death toll.
But the numbers have been rising recently, and Germany’s disease control centre reported 2,034 new cases of Covid-19 on Saturday, the first time the daily national increase has topped 2,000 since the end of April.
The Robert Koch Institute said coronavirus outbreaks are being reported in nursing homes, hospitals, schools and "especially among travellers and in the context of religious or family events".
Germany’s states are in the process of bringing students back the classroom.
But in Berlin, one of the first states to return, at least 41 schools this week reported that students or teachers have become infected, and hundreds of them have been put into quarantine.
