BBC News
There are calls for Jersey's health authorities to ease restrictions that are stopping island choirs from singing together in person.
Under the current guidance, singing is not advised either inside or outside due to the risk of spreading coronavirus.
Nicki Kennedy, who set up a virtual choir during lockdown, is frustrated by the lack of clear guidance about when that might change, after ministers suggested the restrictions may be in place for the rest of the year.
Some good(ish) news on singing. A recent study (summary below) shows that soft singing (not loud) may have little more risk than talking – but do note that it has not yet been peer reviewed, and only applies to singing softly. It was also a highly controlled study with a number of individuals singing separately. Clearly more work needs to be done, and this is just a preliminary testing experiment.
“Speaking and singing show steep increases in mass concentration with increase in volume (spanning a factor of 20-30 across the dynamic range measured, p<1×10-5). At the quietest volume (50 to 60 dB), neither singing (p=0.19) or speaking (p=0.20) were significantly different to breathing. At the loudest volume (90 to 100 dB), a statistically significant difference (p<1×10-5) is observed between singing and speaking, but with singing only generating a factor of between 1.5 and 3.4 more aerosol mass. Guidelines should create recommendations based on the volume and duration of the vocalisation, the number of participants and the environment in which the activity occurs, rather than the type of vocalisation. Mitigations such as the use of amplification and increased attention to ventilation should be employed where practicable.”
It does NOT apply to choirs, as they state, group singing was not studied, and would probably be a greater risk. Other studies of infections (further below) confirm that choirs and group singing, as well as singing loudly, remains a risk.
Studies also suggest that ventilation helps, so soft singing outside is even less risky. But it does look hopeful for some future with singing, even if the Herald Angels may be rather muted this year.
The full article is at:
Comparing the Respirable Aerosol Concentrations and Particle Size Distributions Generated by Singing, Speaking and Breathing
There are calls for Jersey's health authorities to ease restrictions that are stopping island choirs from singing together in person.
Under the current guidance, singing is not advised either inside or outside due to the risk of spreading coronavirus.
Nicki Kennedy, who set up a virtual choir during lockdown, is frustrated by the lack of clear guidance about when that might change, after ministers suggested the restrictions may be in place for the rest of the year.
Some good(ish) news on singing. A recent study (summary below) shows that soft singing (not loud) may have little more risk than talking – but do note that it has not yet been peer reviewed, and only applies to singing softly. It was also a highly controlled study with a number of individuals singing separately. Clearly more work needs to be done, and this is just a preliminary testing experiment.
“Speaking and singing show steep increases in mass concentration with increase in volume (spanning a factor of 20-30 across the dynamic range measured, p<1×10-5). At the quietest volume (50 to 60 dB), neither singing (p=0.19) or speaking (p=0.20) were significantly different to breathing. At the loudest volume (90 to 100 dB), a statistically significant difference (p<1×10-5) is observed between singing and speaking, but with singing only generating a factor of between 1.5 and 3.4 more aerosol mass. Guidelines should create recommendations based on the volume and duration of the vocalisation, the number of participants and the environment in which the activity occurs, rather than the type of vocalisation. Mitigations such as the use of amplification and increased attention to ventilation should be employed where practicable.”
It does NOT apply to choirs, as they state, group singing was not studied, and would probably be a greater risk. Other studies of infections (further below) confirm that choirs and group singing, as well as singing loudly, remains a risk.
Studies also suggest that ventilation helps, so soft singing outside is even less risky. But it does look hopeful for some future with singing, even if the Herald Angels may be rather muted this year.
The full article is at:
Comparing the Respirable Aerosol Concentrations and Particle Size Distributions Generated by Singing, Speaking and Breathing
https://chemrxiv.org/articles/preprint/Comparing_the_Respirable_Aerosol_Concentrations_and_Particle_Size_Distributions_Generated_by_Singing_Speaking_and_Breathing/12789221
And it notes: “These are preliminary reports that have not been peer-reviewed. They should not be regarded as conclusive, guide clinical practice/health-related behavior, or be reported in news media as established information.”
Despite that, some rather misleading précis which omit that it is a preprint not peer reviewed have appeared. or put that just into one sentence, whereas it is extremely important in any scientific study.
A summary of the findings:
https://www.sciencefocus.com/news/spread-of-covid-19-doesnt-depend-on-what-you-sing-but-how-loud-you-sing-it/
Singing is no more risky than talking when its comes to the possibility of coronavirus transmission but it all depends on how loud a person is, scientists have said.
In a new study, which is yet to be peer-reviewed, researchers at the University of Bristol have found that speaking and singing generate similar amounts of aerosol droplets when the sound volumes are the same.
They found that higher volume was associated with an increase in aerosol mass in both speaking and singing, with the loudest level generating up to 30 times more aerosol mass than the lowest volume.
However, they said there were no significant differences in aerosol production between genders or among different genres of music such as choral, musical theatre, opera, jazz, gospel rock or pop.
As part of an ongoing research project, called Perform, the researchers looked at the amounts of aerosols and droplets generated by a large group of 25 professional performers that were up to 20 micrometres (0.02m) in diameter.
The singers performed a range of exercises including breathing, speaking, coughing, and singing at a hospital operating theatre with a “zero aerosol” background.
Dr Florence Gregson, a researcher at the University of Bristol and first author on study, said using this hospital setting setting meant “any aerosol we detected with our measurements, we could directly attribute only to what the singer had produced”.
The experiments included singing and speaking Happy Birthday at different sound levels, between the ranges of 50–60 decibels (dB), 70-80 dB and 90-100 dB.
At the loudest level, singing generated more aerosol particles than speaking but the researchers said that this difference was “very modest”.
Based on their findings, the researchers said ensuring adequate ventilation in the venue may be more important than restricting a specific activity.
Jonathan Reid, an expert in aerosol science at the University of Bristol and a corresponding author on the paper, said: “The study has shown the transmission of viruses in small aerosol particles generated when someone sings or speaks are equally possible with both activities generating similar numbers of particles.
“Our research has provided a rigorous scientific basis for COVID-19 recommendations for arts venues to operate safely for both the performers and audience by ensuring that spaces are appropriately ventilated to reduce the risk of airborne transmission.”
Dr Julian Tang, honorary associate professor in respiratory sciences at the University of Leicester, who was not involved in the study, said:
“Also, the study was performed on individual singers one at a time – when the particle profile was found to be similar to talking. The risk is amplified when a group of singers are singing together, eg singing to an audience, whether in churches or concert halls or theatres. "
“This may also affect the airflow dynamics of that air volume which may be more than the individual contributions from each singer via some complex resonant entrainment airflow dynamics that may propel these aerosols further. It is not comparable to the quiet breathing of the audience whose breathing will not be synchronised in a coordinated manner – like the exhalations of the choir – or talking to each other on a one-to-one basis.
“The risks should not be overly underestimated or played down because of this – we don’t want choir members getting infected and potentially dying from COVID-19 whilst doing what they love.”
He added: “It is a nice study but not exactly representative of the real whole choir dynamic which really needs further study to truly assess the risk of such large volume synchronised singing vocalisations/exhalations.”
This is a handy Q&A which gives details of how the study was done:
https://www.pri.org/stories/2020-08-13/choirs-age-coronavirus-new-study-looks-risks-singing
Also to note:
“This may also affect the airflow dynamics of that air volume which may be more than the individual contributions from each singer via some complex resonant entrainment airflow dynamics that may propel these aerosols further. It is not comparable to the quiet breathing of the audience whose breathing will not be synchronised in a coordinated manner – like the exhalations of the choir – or talking to each other on a one-to-one basis.
“The risks should not be overly underestimated or played down because of this – we don’t want choir members getting infected and potentially dying from COVID-19 whilst doing what they love.”
He added: “It is a nice study but not exactly representative of the real whole choir dynamic which really needs further study to truly assess the risk of such large volume synchronised singing vocalisations/exhalations.”
This is a handy Q&A which gives details of how the study was done:
https://www.pri.org/stories/2020-08-13/choirs-age-coronavirus-new-study-looks-risks-singing
Also to note:
https://www.cdc.gov/mmwr/volumes/69/wr/mm6919e6.htm
Choir practice attendees had multiple opportunities for droplet transmission from close contact or fomite transmission (9), and the act of singing itself might have contributed to SARS-CoV-2 transmission. Aerosol emission during speech has been correlated with loudness of vocalization, and certain persons, who release an order of magnitude more particles than their peers, have been referred to as superemitters and have been hypothesized to contribute to superspeading events (1). Members had an intense and prolonged exposure, singing while sitting 6–10 inches from one another, possibly emitting aerosols. his outbreak of COVID-19 with a high secondary attack rate indicates that SARS-CoV-2 might be highly transmissible in certain settings, including group singing events.
https://www.theguardian.com/world/2020/may/17/did-singing-together-spread-coronavirus-to-four-choirs
Jamie Lloyd-Smith, an infectious diseases researcher at University College Los Angeles, said it was possible that an infected singer might disperse viral particles further than other infected individuals. “One could imagine that really trying to project your voice would also project more droplets and aerosols,” he told the Los Angeles Times. In this way, the virus would cause increased numbers of infections.
https://www.abc.net.au/news/health/2020-06-14/how-can-we-resume-choir-practice-without-spreading-coronavirus/12344812
Experts are mostly singing from the song sheet on this one — singing is a very effective way of spreading COVID-19.
To understand why, we need to take a quick look at how coronavirus spreads. When someone who's infected with COVID-19 coughs, sneezes, talks loudly or sings, they spray out a shower of secretions. These include larger respiratory droplets or aerosols, which are tiny particles of 5 microns or less in diameter, that can carry the virus. Aerosol particles are so tiny and light that they can remain suspended in the air, rather than quickly falling to the ground like a larger, heavier respiratory droplet.
It's this viral 'weather system' that can potentially spread coronavirus, says fluid physics expert Professor Con Doolan. If you're standing too close to an infected person when they cough or sing, you could breathe in the particles they have projected into the air. A cough can push this 'weather system' up to two metres away, and while we don't know exactly how far singing projects particles it could be further than a cough, says epidemiologist and World Health Organisation (WHO) advisor Mary-Louise McLaws. Someone vocalising an 'aah' sound followed by 10 seconds of normal breathing emits around 60 per cent more aerosols than 30 seconds of repeated coughing, research from 2009 found.
It's also the way your mouth moves when you sing that makes it such an effective way to transfer the virus. Vocologist Heather Nelson, who conducts a choir in Missouri in the US, says there are a few things going on. When you sing vowels the mouth is wide open so aerosols are completely unobstructed. When you sing plosive consonants like 'p' and 'b', a large puff of air is produced so large droplets are expelled. "Also, even amateurs sing louder than they speak so that increased energy means we are just going to spit further," Dr Nelson says.
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