A mandate for camouflage in North Carolina schools in the first weeks of the Delta variant’s jump has resulted in a lower infection rate among school children and staff members than reported in the wider community, according to a new report from ABC Science Collaborative.
Published in the journal Pediatrics, the analysis includes data from 20 school districts in North Carolina that conducted a summer school or year-round school between June 14, 2021 and August 13, 2021. The Delta variant became the dominant strain of SARS-CoV-2. circulating in the United States in early July 2021
The data were presented by 783 K-12 schools, representing 59,561 students and 11,854 employees who attended in person. School districts in the analysis follow the North Carolina Department of Health and Human Services (NCDHHS) StrongSchoolsNC Toolkit, which recommends, but does not require, at least three feet of physical distance between people. The mandate for a state mask for K-12 settings is in effect during the study period.
ABC’s scientific collaboration analyzes the COVID-19 data provided by the domains. Two measures were used to assess the prevalence of Delta in schools: A ratio showing community-acquired to school-acquired cases and the predicted secondary attack, or the degree of infection acquired in school.
During the study, 808 community-acquired cases were reported against 64 school-acquired cases. The Delta variant has a reproductive number of about 7, which means that on average in the community one person infected with the Delta variant infects 7 others. However, in schools that apply universal masking, for every 13 people who acquired COVID-19 outside of school, one person acquired COVID-19 within the schools.
As a result of exposure to COVID-19 in schools, 2,431 close contacts were quarantined and 64 people received infections in schools, resulting in a secondary attack rate of 2.6%. This secondary attack rate is slightly higher than the secondary attack rate of approximately 1% found by ABC Science Collaborative before the Delta variant appeared. This is probably due to the more contagious nature of the Delta variant.
The results of this study are extremely encouraging for the health and safety of students and staff attending schools where universal camouflage is available. The Delta variant is more portable than previous ancestral variants, but school transmission may continue to be low with vaccination among those eligible, strict adherence to camouflage, and avoidance of pandemic fatigue. “
Kanecia Zimmerman, MD, MPH, Co-Chair, ABC Science Collaborative
Although the survey did not allow for a comparison with an unmasked environment, as there is a mask mandate throughout the country, data from other schools without a mask mandate in July-August 2021 show that these schools are 3.5 times more likely to to have school-related COVID-19 outbreaks from schools in this study that require camouflage.
The data from this study also emphasize the importance of staying vigilant during the school day, when strict adherence to the mask may not be possible.
“We look forward to fall and winter, and lunch and extracurricular activities will be areas that require extra attention to limit the transmission of COVID-19 to schools,” said Danny Benjamin, PhD, PhD, MPH, co-chair of ABC Science. Collaborative. “As pediatricians and public health experts, we encourage schools to put in place mitigation strategies, such as vaccinations, camouflage and outdoor nutrition, to protect students and staff.”
Duke University Health System
Reference in the magazine:
Boutzoukas, AE, and others. (2021) School safety, camouflage and delta option. Pediatrics. doi.org/10.1542/peds.2021-054396.