University of Florida Study : Schools can Implement Testing Protocols to Promote In-person learning while effectively mitigating transmission risk

the staff of the Ridgewood blog

Ridgewood NJ,  a study conducted by the University of Florida and the Florida Department of Health, published in JAMA, investigated the impact of student quarantine and testing protocols at K-12 schools in Alachua County, Florida. Data indicate that the COVID-19 incubation period in children is 6 to 7 days, shorter than the 4 to 5 days in adults. The county implemented 14-day self-quarantine for students exposed to known COVID-19 cases, and students were allowed to return to school early if they received a negative RT-PCR diagnostic test on Day 9 or later.

The rationale for this program was that SARS-CoV-2 infection should be detectable by Day 9 and that students who tested negative could safely return to school the next day. Out of 799 students who received a negative test under this program, only 1 developed symptomatic disease after returning to school, and genomic data indicate that the student was actually infected through a different exposure than the one that prompted quarantine. The program to enable students to end their quarantine period early reduced the total number of missed school days by more than 30% without resulting in any additional transmission. This study provides evidence that schools can implement testing protocols to promote in-person learning while effectively mitigating transmission risk.

A study conducted by the US CDC COVID-19 Response Team and school and public health officials in Georgia, published in the CDC’s MMWR, found that half of school-associated cases initiated from teacher-to-teacher transmission and then spread from teachers to students. The researchers evaluated data from 24 days of in-person learning at elementary schools in a single school district, which included approximately 2,600 students and 700 staff. In total 9 clusters of cases were identified, involving 13 teachers, 32 students, and 18 additional instances of household transmission. Of the 31 school-associated cases, 15 were students who are believed to have been infected following transmission between teachers. Notably, all 9 of the school clusters “involved less than ideal physical distancing, and five involved inadequate mask use by students.” The “central” role of teachers in school-based transmission provides support for vaccinating teachers in order to mitigate transmission risk during in-person classes. Current US CDC guidance indicates that teachers need not be vaccinated before schools can reopen, but many teachers unions are calling for changes to existing guidance and policies that would prioritize teachers as essential workers in order to provide protection before resuming in-person learning.