School Outbreak Investigation
The first publication of a mass COVID19 outbreak within a school was published over the weekend. A high school that reopened in Israel. What happened?
March 13: Complete closure of all schools
May 3: Only kindergarten, grades 1-3, grades 11-12 opened
May 17: All schools reopened
May 27: First major school outbreak at a public high school
May 28: The school was closed
May 28-30: Everyone at the school was COVID19 tested
Mid-June: 87 contacts outside of school positive (e.g. siblings, friends, teammates, student parents)
June 30: 65% students recovered and 64% staff recovered (two negative PCR results)
Attack rate was 13.2% among students and 16.6% among staff. No one was hospitalized. Grades 7-9 had the highest transmission.
The highest classroom rate was in 9th grade (20 cases in one class). The second highest was in 7th grade (14 cases in one class). The third and fourth highest were in 9th grade (13 cases in each class).
What can we (in the United States) learn from this? Avoid the three C’s:
Closed spaces with poor ventilation (Outdoor classes should be considered. There was a heatwave in Isreal during this outbreak and this wasn’t possible)
Crowded places (We need small classroom sizes. Isreal’s classes were crowded: 35-38 studentsper class)
Close-contact settings (Minimize student mixing; wear facemasks; teachers set example)
Love, your local epidemiologist
Data Source: Stein-Zamir et al., (2020) A large COVID19 outbreak in a high school 10 days after schools’ reopening, Isreal, May 2020. https://www.eurosurveillance.org/content/10.2807/1560-7917.ES.2020.25.29.2001352#html_fulltext