Personal protective equipment (PPE) remains in short supply. Current decontamination methods are complex, slow, expensive and particularly ill-suited for low to middle income nations where the need is greatest. We propose a low temperature, ambient humidity decontamination method (WASP-D) based on the thirty minute or less half-life of Sars-CoV-2 (and other common pathogens) at temperatures above 45°C, combined with the observation that most PPE are designed to be safely transported and stored at temperatures below 50°C. Decontamination at 12 hours, 46°C (115°F) and ambient humidity should consistently reduce SARS-CoV-2 viral load by a factor of 10−6, without negatively affecting PPE materials or performance.

Heat is an established method to inactivate coronaviruses, and there is utility in using heat to reduce viral load on common touch points in vehicles exposed to a person shedding SARS-CoV-2. As SARS-CoV-2 is a Biosafety level (BSL)-3 pathogen, real-world testing of heat as a sanitation method for public and private vehicles becomes a challenge, requiring a surrogate coronavirus that can be handled safely outside of a BSL-3 facility. In this study, we used Bovine Coronavirus (BCoV) as a surrogate for SARS-CoV-2 to test the efficacy of heat-based betacoronavirus inactivation. In vitro, a 30-minute exposure to 56°C completely inactivated BCoV in solution, and a 15-minute exposure reduced recovery of BCoV >1000-fold. When heated to 56°C for 15 minutes, the infectivity of BCoV spotted and dried on typical porous and non-porous automobile interior materials was reduced by 99 - 99.99%. When BCoV was spotted and dried on hard plastic (seat) material placed inside an out of service transit bus, 56°C heat for 30 minutes reduced BCoV infectivity 85 - 99.5%. Thus, 56°C is an accessible, rapid, and effective method to inactivate coronaviruses inside motor vehicles.