USA, Teacher learned she was positive 2 days later
https://www.washingtonpost.com/health...
Marin County, California, May 19, under 12s
One teacher, not vaccinated, feeling fatigued with some nasal congestion
Worked on, toot of mask for class reading
Air filter, windows open on two walls
6 feet between desks
Learned she was positive two days later
12 of 24 had been infected
6 symptomatic, 6 asymptomatic
Mostly in the two rows closest to her desk
Outbreak spread to other classes
Siblings and parents, including some who were fully vaccinated
Tracy Lam-Hine, epidemiologist for the county
everyone lets their guard down — but the thing is delta takes advantage of slippage from any kind of protective measures
Children under 12, ineligible for vaccines
COVID-19 Projections for K12 Schools in Fall 2021: Significant Transmission without Interventions
https://www.medrxiv.org/content/10.11...
Without testing and masking R0 = 4.0
More than 75% of susceptible students get infected within three
months in all settings
With masks, R0 = 2.0
The proportion infected drops to approximately 50%
Testing further drops infections
High, 22%
Mid, 16%
Low, 13%
Conclusion
Without interventions in place, the vast majority of susceptible students will become infected through the semester.
Universal masking can reduce student infections by 26-78%, and biweekly testing along with masking reduces infections by another 50%.
To prevent new infections in the community, limit school absences, and maintain in-person learning, interventions such as masking and testing must be implemented widely, especially among elementary school settings in which children are not yet eligible for the vaccine
Category
📚
Learning