Sing softly and do not shake to reduce the risk of Covid-19 spread, new research suggests, offering a ray of hope for musicians who are restricted from performing in public.
Music makers have been hit hard by the coronavirus pandemic, with singing, such as playing woodwinds and brass instruments considered a potentially high risk of spreading the disease – a concern fueled by outbreaks in choirs.
As a result, only professional rehearsals and performances outside, until recently, were allowed in England, and even then only with a number of precautionary measures.
But the research offers hope to artists who would like to get on stage as soon as possible.
“It’s not about the vocalization – whether it’s singing or speaking – it’s about the volume,” said Jonathan Reid, a professor of physical chemistry at the University of Bristol and co-author of the study. “Just by singing a little softer, you really reduce the risk.”
In a study that has not yet been peer-reviewed, the team reports how they asked 25 professional singers to breathe, talk, cough and sing in funnels. They then measured the mass of small droplets suspended in the air, known as aerosols, that were produced. The experiments were set up in an orthopedic operating theater, an institution chosen for the lack of aerosol background.
While one route by which Covid-19 is spread via large droplets, largely produced when someone coughs and which falls to the ground within a few meters, Reid said aerosols were another possible route, noting such small droplets can hang in the air.
The team found that the results of their study varied across participants, however, at the lowest volume generated singing and speaking a similar mass of aerosols as breathing.
But when the team asked participants to recite Happy Birthday on various volumes, they found the loudest singing and speaking – 90-100dB – produced about 36 and 24 times the mass of aerosols respectively, generated by breathing.
“The volume of activity, whether it’s talking or singing softly or talking loudly or singing, is really the main factor in governing the aerosol mass that is generated,” Reid said, adding that while singing something higher mass aerosols generated than speech, at least when sound, the difference is very small compared to the effect of volume.
Co-author Declan Costello, an ear, nose and throat surgeon at Wexham Park Hospital, noted other factors, including the size of the space and ventilation and the duration of loud vocalization, play an important role in potential infection risk.
In other words, singing in a cathedral could pose a lower risk of spreading Covid-19 than writing about a full pub. “Intuitively, that seems to be the case, assuming people speak or sing the same volume,” Costello said.
However, the study has limitations: it only measured aerosols produced by one individual at a time, while it did not see how much virus was contained in the aerosol as the real risk of infection by the levels of aerosol produced.
“It’s a fun study, but not exactly representative of the real high choir dynamics, which really needs further study to really assess the risk of such large volume synchronized song vocalizations / exhalations,” said Dr. Julian Tang, an honorary lecturer professor of respiratory sciences at the University of Leicester, who was not involved in the work.
The team said their findings had already contributed to new guidance for England released on August 15 by the Department of Digital, Culture, Media and Sport, which jointly supported the study.
The Secretary of Culture, Oliver Dowden, said: ‘I know that singing is an important passion and time-saver for many people who I am sure I will share in welcoming the findings of this important study. We have worked closely with medical experts during this very crisis to develop our understanding of Covid-19, and we have now updated our guidance in the light of these findings so that people can return to perform safely together. ”
John Gilhooly, the artistic and executive director of Wigmore Hall in London, said the ‘music industry’s a huge debt to Declan Costello and his research colleagues who did all this work without compensation. It means we can start to get bigger room groups on stage and that we do not have to lose the first six rows of audience seats. ”
Alex Beard, chief executive of the Royal Opera House, said the relaxation of social media rules from 3 meters to 2 meters for singers and woodwinds and brass players “was a big step forward” allowing more players to perform together in the theaters pit as the company resumes live events with a socially distant audience this October.
