A review article this time, “An Overview on the Role of Relative Humidity in Airborne Transmission of SARS-CoV-2 in Indoor Environments“. It’s pretty much all there in the title… they looked at the state of current research and tried to summarize it here, specifically with an eye towards actionable choices for people managing buildings. Abstract below:
COVID-19 disease is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which originated in Wuhan, China and spread with an astonishing rate across the world. The transmission routes of SARS-CoV-2 are still debated, but recent evidence strongly suggeststhat COVID-19 could be transmitted via air in poorly ventilated places. Some studies also suggest the higher surface stability of SARS-CoV-2 as compared to SARS-CoV-1. It is also possible that small viral particles may enter into indoor environments from the various emission sources aided by environmental factors such as relative humidity, wind speed, temperature, thus representing a type of an aerosol transmission. Here, we explore the roleof relative humidity in airborne transmission ofSARS-CoV-2 virus in indoor environments based on recent studies around the world. Humidity affects both the evaporation kinematics and particle growth. In dry indoor places i.e., less humidity (<40% RH), the chances of airborne transmission of SARS-CoV-2are higher than that of humid places (i.e., >90% RH). Based on earlier studies, a relative humidity of 40–60% was found to be optimal for human healthin indoor places. Thus, it is extremely important to seta minimum relative humidity standard for indoor environments such as hospitals, offices and public transports for minimization of airborne spread of SARS-CoV-2.