On May 19, 2021, an elementary school teacher in Marion County, California took her mask off to read to her class of students under the age of 12 and within days half of her students were infected by the Delta Variant. The school had otherwise been cautious by spacing the desks 6 feet apart and students wore masks. Windows were open on two walls and there was some sort of air filter in the room.
The selfish and irresponsible teacher however was UNVACCINATED. Most of the infected children were in the first two rows closes to the teachers desk. Six children had symptoms and six were asymptomatic. Several children did not get tested.
The teacher tested positive for COVID-19 two days after reading to her students without a mask. At all other times, she tended to wear her mask. The outbreak spread to other classes and student siblings and parents, some who were fully vaccinated.
Tracy Lam-Hine, the epidemiologist for the county said, “Everyone lets their guard down, but the thing is Delta takes advantage of any slippage from any kind of protective measures.”
A computer model found that without masking and testing each student who is infected could infect four other students. More than 75% of susceptible students will become infected within 3 months.
With comprehensive mask wearing each student could still infect two other students. The proportion of students infected drops by about 50%.
Mask wearing combined with twice weekly testing results in 22% of students infected if mask wearing is low, 16% if mask wearing is medium and if all student wore masks the percent infected would drop down to 13% of students infected over the course of a semester.
The report concluded, that without interventions in place the vast majority of students will become infected throughout the semester. Universal masking can reduce the infections by 26% to 78% and biweekly testing can reduce infections by another 50%. To prevent infections in the community, masking and biweekly testing should be implemented especially for students under the age of 12 who are not eligible for the vaccine.