This week’s summary focuses on indoor air quality as a critical part of reducing within-school and within-classroom virus transmission risk.

• A recent piece in JAMA discusses COVID-19 transmission reduction in terms of source controls, such as masking and distancing, and engineering controls, including ventilation and air filtration. Because SARS-CoV-2, the virus that causes COVID-19, is transmitted through airborne particles, engineering controls can reduce risk of within-room, far-field transmission. Simply put, increasing air changes per hour and implementing air filtration are important mitigation strategies that reduce risk in the current situation and for other respiratory diseases that spread via airborne transmission.
• Relatedly, a new column out of the Harvard Kennedy School’s Belfer Center for Science and International Affairs focuses on strategies to reduce airborne virus transmission in the home — though the tips are relevant and useful for any indoor setting. In conjunction with prior guidance on the 3 S’s (Stay Distant, Stay Clean, Stay Vigilant), the authors provide advice on aiming for an air change rate of 4-6 times per hour through Fresh Air, Filtered Air, and Flowing Air.
• Previous reporting based on engineering simulations, a Brookings Institution blog post, and discussion in a prior roundup all highlight the importance of air flow in classrooms and emphasize the importance for curbing within-school spread during the current pandemic as well as in the future.