Children release just a quarter of the aerosolised particles as adults while breathing, speaking and singing, according to a study.
The study, Journal of the Royal Society Interface, may be useful for making decisions about risk management in schools, CNN reported.
In the study, a team of researchers including those from Humboldt-Universitat zu Berlin, in Germany, analysed 15 children between the ages of 8 and 10 and compared the rates at which they emitted particles for various vocal tasks with the emission rates of 15 adults.
They measured the number of particles emitted over time as well as the volume of particles emitted.
The researchers found that overall, children emit particles at a lower rate and a lower volume than adults. However, there was no significant difference in the volume of particle releases between the groups when it came to shouting.
The study found that children are also, on average, less loud than adults, which partially accounts for the difference in observed aerosolised particle emission between the groups, the report said.
The results may partially be explained by differences in respiratory anatomy between children and adults, Pedro Piedra, professor at Baylor College of Medicine, was quoted as saying.
For example, children have smaller lung sizes and shorter vocal cords, said Piedra who was not involved in the study.
Studies have shown that children have only slightly lower — and probably clinically insignificant — Covid-19 viral loads than adults. Yet children are less susceptible to infection and more likely to be asymptomatic, the report said.
“In the context of a pandemic, kids on average release fewer respiratory droplets and aerosols than adults do, and may be less likely to transmit [Covid-19],” Linsey Marr, professor of civil and environmental engineering at Virginia Tech, was quoted as saying.
However, there is a lot of variability in particles emitted from person to person, “so even though on average kids emit less, a high-emitting kid still emits more than a low-emitting adult,” cautioned Marr, who was also not part of the study.
According to Piedra, the main difference between children and adults is their disease severity with Covid-19.
As countries weigh decisions on lifting school mask mandates, Piedro said it’s important to “not let down our guards and say that masking is not needed.”
Even though children “may not be able to generate the same energy in their voice for emission of small particle aerosols, they’re still very efficient transmitters,” he said.