There have been a number of reports of coronavirus spreading rapidly through choirs and other musical groups before lockdown.

On March 10th – during that period when no-one was quite sure how serious the threat was – one choir met for a rehearsal in Washington state. They used hand sanitizer when they arrived and avoided handshakes and hugs. In spite of the precautions 45 of the 60 people who attended developed the virus and two died.

The choir I sing with, Kingston Choral Society, was rehearsing as late as 12th March and, at that time, was still planning to go ahead with a concert on 21st March. I had already dropped out a week or two before, concerned about my vulnerability. By the weekend of 15th March there was enough concern to cancel the final rehearsal and postpone the concert until June. That, of course, was over optimistic and a June concert is not now going to happen. Fortunately my choir does not seem to have been a hotbed of infection.

I had also spotted a curious story on the BBC about two choirs in Yorkshire that, in retrospect, may have suffered from coronavirus back in January, long before the first recorded case in the UK. The two choirs had members in common, and the partner of one member had recently returned from Wuhan, with a hacking cough.

So does that mean that people project droplets more widely when they are singing?

Prof Christian Kähler of the Military University, Munich has carried out some research, from his perspective as an expert in fluid mechanics. He reports:

I have been studying how droplets and aerosols behave for decades and I was very doubtful that musicians and singers were spreading the virus. So I decided to measure just how strong was the airflow from them. We studied singing in low and high frequencies and all sorts of things like that. We also studied different instruments. And based on the flow analysis we did of these performances we could clearly see what was going on.

The conclusion was that singing is quite safe and did not in itself cause the outbreaks in choirs.  However some musical instruments do have high airflows. I rather imagined that large brass instruments would be the worst, but it seems that the flute is the chief culprit.

So why has coronavirus taken hold in some choirs? Well, put 100 or so people in close proximity in a room for a couple of hours and you have ideal conditions for spreading the virus. Choir members are a friendly lot and they mix even more before the rehearsal begins and during the tea break.

Of course, there are lots of online choirs to choose from at the moment, but it isn’t quite the same as making a wonderful sound together surrounded by dozens of other singers. We will all want to get back together again soon, but social distancing is going to be really difficult for a large choir, so I’m afraid there may be quite a wait before we are able to do so.

Please note

We have been in full self-isolation since 16th March to protect my husband whose immune system is compromised.

If you are in self-isolation then join the Lib Dems in self-isolation Facebook group.

You can find my previous Isolation diaries here.

* Mary Reid is a contributing editor on Lib Dem Voice. She was a councillor in Kingston upon Thames, where she is still very active with the local party, and is the Hon President of Kingston Lib Dems.