Scientists at Charité – Universitätsmedizin Berlin and Technische Universität Berlin have now published a preprint of a study investigating the potential airborne transmission of the virus when children sing together. Their findings could contribute to more specific hygiene measures for music instruction.
The current restrictions for choir and ensemble singing have had a far-reaching impact, including on children and youth. Communal singing is not only a compulsory part of school education; it also plays an important role in the socio-emotional development of children and youth. The restrictions have affected both music lessons in schools throughout Germany as well as extracurriculars offered by music schools and children’s and youth choirs. “In the current pilot study conducted by the Hermann Rietschel Institute at TU Berlin and the Department of Audiology and Phoniatrics at Charité́ – Universitätsmedizin Berlin, we are collecting data for the first time on aerosol formation when children sing,” explains Professor Dr. Martin Kriegel, head of the Hermann Rietschel Institute.
Four experienced members each from the Berliner Staats- und Domchor boys’ choir and the Sing Akademie zu Berlin girls’ choir participated in the study. The tests were conducted in the cleanroom at the Hermann Rietschel Institute, where the children completed various tasks while a laser particle counter determined the number of aerosols formed ranging from 0.3 to 25 micrometers in size. In addition to the particle measurements, the scientists recorded the volume level during the different tasks. They also integrated a task more reflective of children’s behavior, asking the children to yell a number of times, such as when cheering after a goal at a football game.
“Our results show that children’s aerosol emissions are also significantly higher when singing versus speaking. However, they vary greatly and are far lower than adults’ emissions,” says Professor Dr. Dirk Mürbe, director of the Department of Audiology and Phoniatrics at Charité́ – Universitätsmedizin Berlin: “We believe that a number of factors contribute to the lower number of emissions. Children’s vocal strength when singing differs from that of adults. Additionally, a child’s vocal chords vibrate differently, producing not only the characteristic childlike sound but also fewer aerosols.”
“Interestingly, we recorded at times higher aerosol emissions when the children cheered compared to when adults sing,” adds Kriegel. The results of the study are now to be used to create a more detailed hygiene concept for singing in and outside of schools and thus create framework conditions which enable children’s and youth choirs to resume singing under specific conditions. Important factors include the number and positioning of singing children, rehearsal duration, and particularly the room size and effective ventilation concepts. The lower aerosol formation produced by children when singing is a new factor which can be considered in the overall evaluation of individual concepts.