Thermal Inactivation of Aerosolized SARS-CoV-2

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread worldwide with its different variants. The transmission efficiency of the new variants is much higher than the existing ones. Therefore, developing new preventive measures based on the transmission routes of the virus is needed to limit the spread. The possible transmission routes include direct contact with surfaces contaminated with droplets secreted by patients and airborne viral transmission from person to person. Thermal inactivation is a preventive measure that applies high temperature to objects or fluids, as has been reported previously. However, inactivation data of aerosolized SARS-CoV-2 exposed to heat for a short time at high temperatures are not in the literature yet. We evaluated the inactivation of the aerosolized virus while passing through an electric heater. The virus inactivation test experiments were conducted at two temperatures of the heater’s outlet air, 150±5oC, and 220±5 oC, at an air flow rate of 0.6 m3/h (10 L/min) and heat exposure time of 1.44 s. The loss in viability of the virus at 150 oC and 220 oC was measured as 99.900% and 99.999%, respectively. The results indicate that the high-temperature inactivation of SARS-CoV-2 may potentially reduce aerosolized viral indoors.