in a recommendation letter imgrund wrote for sickkids hospital
,he supports the use of masks in schools, saying the viral load on a mask will be low if every student and teacher is wearing one and washing their hands.
face shields are another option, he says, for students in grade three and under, if masks are difficult.
still, face
masks are better than face shields,for containing droplets, says banerji, adding that even though face shields may be better for communication and can protect particles from entering the eyes, if kids are coughing, the shields won’t contain droplets as well as a face mask.
“some studies have shown that young children may not transmit as much [covid-19] because they don’t have the strength to cough up the particles,” she says. “for example, tuberculosis is not really something that
children transmit
. but covid-19 is an evolving science so we don’t really know.”
this uncertainty makes it even more critical that we make decisions about how to get kids back into school safely based on what we know — and that’s that distancing and wearing masks slows the spread of the virus.
“if we are asking students to mask and be socially distant, the chance of encountering an infection will be much smaller than the risk of transmitting it,” writes imgrund in the recommendation letter to sickkids hospital.
he suggests “bubble bubbies” of three or less for children in younger grades, where physical distancing is difficult, adding that if a teacher is provided with the proper ppe, this would reduce an individual student’s exposure rate to less than one per cent (in ottawa).
using the most recent numbers from ottawa public health, the biostatistician says if students are wearing masks and staying physically distant in a class of 15, there is a 3.8 per cent chance of encountering another student with transmissible covid-19 infection. imgrund calculated that that number jumps to 25 per cent if a student were to take four classes with pre-covid class sizes, and more than three in four chances, if students have a lunch with 500 students.