The spread of aerosolized SARS-CoV-2, the virus that causes COVID-19, inside public buildings could be suppressed using engineering controls such as effective ventilation, possibly with air filtration and disinfection and avoidance of air recirculation and overcrowding, according to a research letter published yesterday in Environment International.The international group of researchers said the evidence is sufficiently strong for aerosols as an important mode of coronavirus transmission, most of which occurs indoors, and that indoor measures to slow the spread are often easily implemented at relatively low cost.The authors noted that, of two published hospital-based papers and five in press, four identified airborne SARS-CoV-2 RNA, two