Evidence Shows Students Need to Wear Masks in Schools Despite Disinformation

Kevin Kavanaugh, MD

As the Omicron surge subsides, many areas in the United States are rapidly returning to normal. Almost all agree we will face another surge of COVID-19 or another virus in the future. There are many lessons to be learned from the current pandemic, but the most important is how disinformation can divide a nation. Nowhere has this been more evident than the use of masking in schools.
 
At the heart of the misinformation spread by many who advocate against the use of masks in schools is that masks are not effective. Granted, they are not 100% effective, but the use of masks is one of the most important best practices to prevent the spread of disease. Unfortunately, this century-old practice has somehow become controversial in the last 2 years, despite mounting evidence that demonstrates its effectiveness with SARS-CoV-2.

On September 24, 2022, the CDC’s Morbidity and Mortality Weekly Report (MMWR) published a report that clearly demonstrated the usefulness of school masking in Arizona’s 2 largest counties, Maricopa and Pima Counties, which comprise the metropolitan areas of Phoenix and Tucson. This study found that schools which started the 2021-22 academic year without a mask mandate had 3.5 times the number of coronavirus outbreaks as in schools which started the year with universal masking. Another study found that from July 1, 2021, to September 4, 2021, schools without a universal masking requirement “experienced larger increases in pediatric COVID-19 case rates after the start of school compared with counties that had school mask requirements (P < .001).”

Most recently, a multi-institutional report funded by the National Institutes of Health found that 6 school districts with optional masking had 3.6 times the secondary infection rate as 46 institutions with universal masking. This study confirms the 2020 work of Young Joon Park, et al., which reported rates of transmission of SARS-CoV-2 as a function of age. The investigators found that rates of secondary transmission to household contact was the highest for those aged 10 to 19 years. The next highest rate of secondary transmission was the 70 to 79 year age group. Secondary transmission is extremely important, since it is estimated that more than 1 in 4 adults live in a multi-generational (3 or more generations) household, and grandparent caregivers are at the highest risk for severe COVID-19.

Despite the above evidence, many believe the disinformation regarding masks. The assertion that masks will not filter and block a 0.1-micron viral particle ignores the science that documents that the SARS-CoV-2 virus aerosolizes as small droplets which measure between 10 and 100 microns. The dry virus, as measured by electron microscopy, is not a major transmitter of disease between individuals.
 
Masking may hinder a student’s word recognition by hiding a speaker’s mouth and lips. However, to correct this problem would entail the teacher not wearing a mask. Teachers are more susceptible to COVID-19 than students, and 24% of teachers have a co-morbidity risk for severe COVID-19. In addition, loud speech during a presentation has an increased propensity to aerosolize a virus. A solution to this problem may be the clear N95 masks which are being developed by Ford.

The March 2022 report “Getting to and Sustaining the Next Normal. A Roadmap for Living with COVID,” from the Colton Foundation and the Rockefeller Foundations’ Pandemic Prevention Institute, concluded that “based on the extensive data and research…schools and childcare centers can safely remain open by following best practices”; and that “governments should not close schools and childcare facilities unless all other community mitigation measures fail.”

An excellent case study regarding a school district’s implementation of a multi-layered approach to remain open and prevent COVID-19 was written by Amanda Mulcahy in Infection Control Today®. The mitigation strategies included masking, surveillance testing, case identification and tracking, vaccinations, and improvements in ventilation.
 
The highly infective Omicron Variant (BA.1) poses significant challenges to control its spread. Most experts now advocate using KN95 or N95 masks instead of the cloth variety which were found effective with previous variants. The “Stealth Omicron” BA.2 variant may be even more challenging. This variant could be up to 30% more infectious than BA.1 and is thought to be causing the current uptick in SARS-CoV-2 cases in the United Kingdom, where rates are currently up 107% over the last 14 days.

Above all, as pointed out by the “Getting to and Sustaining the Next Normal” report, we need clear guidance on when school mitigation recommendations (“including masking, social distancing, quarantining, reduced class sizes, and outdoor learning”) are to be triggered to enable communities to provide the safest environment possible for the education of our children.