By Agence France-Presse When the Berlin Cathedral Choir gathered for a rehearsal on March 9, the new coronavirus was still a distant concern, with fewer than 50 confirmed cases in the German capital. Berlin Cathedral Choir members were infected during a rehearsal on March 9 when the coronavirus was a distant worry (AFP/File / Odd ANDERSEN / MANILA BULLETIN) But five days later, one of the ensemble's 80 singers contacted choir director Tobias Brommann to say she had tested positive for COVID-19. Within two weeks, around 30 members had tested positive and a further 30 were showing symptoms -- including Brommann himself, who was struck down with a headache, cough and fever. "We also can't be sure if those without symptoms were not infected too, as we have not done antibody tests," Brommann told AFP. Hardly considered an extreme activity up to now, singing -- especially choral singing -- is quickly earning a reputation in the pandemic as about the most dangerous thing you can do. Similar horror stories have emerged from choirs around the world, including one in Amsterdam where 102 singers are reported to have fallen sick with COVID-19. High-risk activity Though much is not yet understood about how the new coronavirus spreads, anecdotal evidence has been enough to convince German authorities that singing is a particularly high-risk activity. Under new freedoms being gradually introduced across the country's states, Germans can meet friends in the park, dine in a restaurant, play sports, go to church, browse the shops, watch football and even go swimming. But singing remains broadly off limits, and it looks likely to stay that way for the foreseeable future. In recommendations for the resumption of church services published in April, the federal government stated that singing should be avoided "because of the increased production of potentially infectious droplets, which can be spread over greater distances". Several states have heeded the advice and banned singing from services. Even Germany's revered Robert Koch Institute (RKI) disease control centre has warned against singing, with RKI head Lothar Wieler saying that "droplets fly particularly far when singing".