Under the first scenario, which simulated the very beginning of a pandemic, the concert-goers were kept close together in the room with no social distancing. In the second, the researchers instituted hygiene measures and larger social distances between the volunteers. In the third, a distance of 1.5 meters (5 feet) 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, partially because many Germans are still away on summer holidays and partially due to fears of participating even with the safety measures taken. 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.

In general, Germany has been praised for its handling of the pandemic with its rapid response and robust testing. It 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 center 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 travelers and in the context of religious or family events.”