Abstract

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.

Competing Interest Statement

The authors have declared no competing interest.

Paper in collection COVID-19 SARS-CoV-2 preprints from medRxiv and bioRxiv