Infectious Disease

Masks and ventilation improvements lowered the incidence of COVID-19 in elementary schools

Source / information

Disclosure:
Gettings and Lanier do not report any relevant financial information. In the study you will find all relevant financial information from all other authors.

ADD SUBJECT TO EMAIL ALARMS

Receive an email when new articles are published

Please enter your email address to receive an email when new articles are published . “data-action =” subscribe “> subscribe

We could not process your request. Please try again later. If you continue to have this problem, please contact [email protected].

Back to Healio

Mask requirements and ventilation improvements reduced the incidence of COVID-19 in elementary schools in Georgia by nearly half, data published in MMWR showed.

Dilution methods such as opening windows and doors and using fans reduced the incidence by 35% when used alone Jenna Gettings, DVMMPH, a CDC Epidemic Intelligence Service Officer embedded in the Georgia Department of Public Health, and colleagues. By adding highly efficient particle-absorbing filters, the incidence could be reduced by 48%.

Source: Adobe Stock.

The researchers found that the incidence in schools where teachers and staff had to use masks was 37% lower.

“Diverse” approach
The study data comes from a survey of 169 elementary schools opened for personal learning in Georgia. The data is from a period of 26 days from November 16 to December 11, 2020.

The COVID-19 incidence rate for all schools combined was 3.08 cases per 500 students enrolled. The incidence rate in the community in counties with schools participating in the study was 1,055 per 100,000 people – or approximately 5.28 per 500 people, the authors reported.

The schools that implemented dilution methods alone (39 schools) had 2.94 cases per 500 students (RR = 0.65; 2.94) [95% CI, 2.48-3.5]). Those who only implemented filtration upgrades (16 schools) had 2.46 cases per 500 students (RR = 0.69; 2.46) [95% CI, 1.84-3.29]). For schools that implemented both dilution methods and filtration upgrades (31 schools), there were 2.22 cases per 500 students (RR = 0.52; 2.22) [95% CI, 1.73-2.84]).

“The prevention of the transmission of SARS-CoV-2 in schools should be diverse,” wrote the authors. “Mask requirements for teachers and staff and improved ventilation are key strategies that elementary schools could implement as part of a multi-component approach to provide safer personal learning environments until vaccines are available for children under the age of 12.”

High school tests
In a second study published in the MMWR Cdr. William A. Lanier, DVM, MPH, DACVPM, a senior epidemiologist with the USDA Food Safety and Inspection Service, and colleagues evaluated two Utah high school COVID-19 testing programs aimed at maintaining extracurricular activities and in-person tuition.

The first test, called “Test to Play”, provided tests every 14 days for students who want to participate in extracurricular activities. The second, called the “Test to Stay”, was compulsory in order to continue the personal lessons.

Test to Play was implemented in 127 of Utah’s 193 public high schools, while Test to Stay was implemented in 13 high schools. For both programs, the Utah Department of Health provided training and rapid antigen test kits for staff who performed school-based testing. Parental permission was required for students to receive tests.

From November 30, 2020 to March 20, 2021, 1,886 (3.2%) of 59,552 students who participated in either program got a positive test result, the researchers reported. Those who tested positive were required to isolate for 10 days from the date of the test.

Lanier and colleagues said the programs “facilitated the completion of approximately 95% of high school extracurricular competitive events and saved an estimated 109,752 in-person teaching days for students.”

“Utah high school’s COVID-19 testing programs saved in-person teaching days and allowed extracurricular activities to continue in accordance with state health policies during a period of high COVID-19 incidence in high school aged people,” they wrote.

“Growing evidence suggests that when schools implement recommended prevention strategies, including consistent and correct use of masks, physical distancing, hand hygiene and improved room ventilation, COVID-19 transmission in schools is rare, while loss of personal life.” Classroom teaching can have an adverse effect on the education of children and their social and emotional wellbeing. “

References:

Gettings J, et al. MMWR Morbid Mortal Wkly Rep. 2021; doi: 10.15585 / mmwr.mm7021e1.

Lanier WA et al. MMWR Morbid Mortal Wkly Rep. 2021; doi: 10.15585 / mmwr.mm7021e2.

perspective

Back to top

Linsey Marr, PhD

Linsey Marr

The first study provides real-world evidence confirming the benefits of masks, ventilation, and filtration in reducing COVID-19 transmission. We know from fundamental scientific principles that these three interventions should work, just as we know that gravity means an apple will fall from a tree instead of floating into space. Masks, while not as good as an N95 and also not worn perfectly, decrease the amount of virus an infected person releases into the air around them and also decrease the amount of virus that other people breathe in from the surrounding air. Ventilation and filtration reduce the amount of virus in the air. Interestingly, the study found no association between a distance of at least 6 feet and the incidence of disease, and between the use of barriers and the incidence of disease. Taken together, these results provide further evidence that COVID-19 is mainly transmitted through aerosols. If it were carried mainly by large droplets, we would expect some benefit from masks, distancements and barriers, but not ventilation and filtration.

Linsey Marr, PhD

Professor of Civil and Environmental Engineering

Virginia Tech University

Disclosure: Marr does not report any relevant financial information.

ADD SUBJECT TO EMAIL ALARMS

Receive an email when new articles are published

Please enter your email address to receive an email when new articles are published . “data-action =” subscribe “> subscribe

We could not process your request. Please try again later. If you continue to have this problem, please contact [email protected].

Back to Healio

COVID-19 Resource Center

COVID-19 Resource Center

Related Articles