Masking, social distancing and vaccinations have been the three-part doctrine of COVID-19 prevention the past two years. Now that workers are returning to the office, facing a possible late-summer COVID-19 surge, it might be time to add a fourth component: ventilation.
An Italian study published March 22 suggested improved ventilation systems could reduce COVID-19 transmission in schools by more than 80 percent. In a review of 10,441 classrooms in Italy’s central Marche region, infections were lower in the 316 classrooms equipped with mechanical ventilation systems. The research, coordinated by the Hume Foundation, found the reduction in cases aligned with the strength of the ventilation system.
American schools, the average at least 45 years old, have notoriously bad ventilation systems that need repair or replacement, according to a 2020 Government Accountability Office report. Some schools don’t have mechanical ventilation systems. Workplaces and public spaces like restaurants and retail stores likely have more efficient, up-to-date systems but the risks remain during periods of high transmission.
As the Omicron variant swept through the state less than two months ago, Dr. Ulysses Wu, Hartford HealthCare’s System Director of Infection Disease and Chief Epidemiologist, offered this caution:
“Don’t go to an indoor dinner with 50 people with poor air circulation where you don’t know if they’re vaccinated or even if they are vaccinated. If you put yourself in risky situations your chances are that you may get infected.”
At the time, we recommended the COVID-19 Indoor Safety Guideline tool, developed by the number-crunchers at the Massachusetts Institute of Technology, that with great specificity allowed people to assess their risk in public spaces, including offices. Connecticut used Centers for Disease Control and Prevention guidance to initially reopen restaurants at 50 percent, later 75 percent, for indoor dining. to balance proper ventilation and crowd size.
Years ago, a Harvard University study of 3,730 hourly employees in 40 buildings with 115 independently ventilated work areas at a large Massachusetts manufacturer showed sick leave increased 53 percent among employees in poorly ventilated areas. Additional research has shown better ventilated classrooms produce lower rates of influenza, asthma attacks and absenteeism. And with less carbon dioxide in the air, whether in a classroom or office, people stay alert longer, think more clearly and ultimately become more productive.
The new National COVD-19 Preparedness plan includes ventilation upgrades in schools funded by the American Rescue Plan Act. In Connecticut, Gov. Ned Lamont earlier this month proposed a grant program to help public school districts pay for air quality improvements in school buildings.
The results of the Italian study revealed the potential benefits:
- Classroom air replaced 2.4 times an hour: 40 percent reduction in infections.
- Classroom air replaced 4 times an hour: 66.8 percent reduction in infections.
- Classroom air replaced 6 times an hour: 82.5 percent reduction in infections.
“One thing the COVID-19 pandemic exposed,” said Gov. Lamont, “is that many school buildings in our state, particularly those that are of a certain age, are in serious need of air quality improvements.”