Elementary schools should establish mask requirements for teachers and staff and improve ventilation to lower the risk of coronavirus spread, the Centers for Disease Control and Prevention (CDC) advised in its latest report. The agency recommends masks for all teachers and students regardless of vaccination status, however.
The CDC released findings from a study in Georgia before vaccines became available, drawing on data from 169 K-5 schools, nearly all of which were public. The study had a low response rate on surveys, and only represented about a quarter of all public school districts in Georgia.
Results showed schools with mask requirements for teachers and staff had a 37% lower COVID-19 incidence, and 39% lower incidence in schools that took steps to improve ventilation, compared to schools without these prevention strategies. Schools that also used filtration systems saw a larger reduction in incidence at 48%.
“Mask requirements for teachers and staff members and improved ventilation were associated with lower incidence,” the CDC report reads.
The CDC and Georgia Department of Health conducted the study in November-December 2020 to see how differing prevention strategies impacted COVID-19 incidence when schools began re-opening. The health department required schools to submit weekly information on COVID-19 infections, and later on, an online survey was sent to all Georgia public K–5 school district leaders and private schools to assess prevention strategies.
Researchers reported an overall 3.08 COVID-19 incidence among students and staff per 500 enrolled students, compared with a 5.28 community incidence per 500 people. Most of the schools were located in metropolitan areas, and about 18% of schools were operating on a 100% in-person schedule. The median class size was 19 students.
The study indicated 65% of schools required masks for teachers and staff and just over half of schools improved ventilation. Other strategies with a lower uptake involved 6 feet of spacing between desks and placing barriers on desks, about 19% and 23% of schools used these measures, respectively.
Mask requirements for students were split down the middle, though the CDC researchers said a 21% drop in virus incidence among schools requiring masks wasn’t statistically significant, compared to schools where mask use for students was optional.
CDC researchers said universal and correct mask use is a low-cost, easy strategy to put in place tp cut infection risk, upholding the agency’s recommendations that mask use is key in schools’ multiprong approach to virus prevention.
Finally, simply opening doors and windows is a cost-effective way to help tamp down on virus transmission, the report says, through schools should consider HEPA filters or UVGI in certain places that are difficult to ventilate, or in nurses’ offices due to a higher likelihood of infected individuals. The CDC acknowledged lower-resourced schools might face challenges in installing air filtration devices, but said cracking doors and windows can still bring improvements.