Airborne murine coronavirus response to low levels of hypochlorous acid, hydrogen peroxide and glycol vapors

Airborne murine coronavirus was assessed for its sensitivity to the vapors of chemicals commonly used to disinfect indoor surfaces. As a model for the chemical sensitivity of airborne SARS-CoV-2, the infectious potential of airborne Mouse Hepatitis Virus (MHV) was tracked in the presence of the following pure chemical vapors, each of which was below its permissible exposure limit (PEL) as regulated by the US National Institute of Occupational Safety and Health (NIOSH): < 50 ppmv for glycol; < 1ppmv for HOCl; and, < 1ppmv for H2O2. Along with its growth media, infectious MHV was aerosolized in a particle size distribution between 0.5 μm and 3.2 μm into a sealed, dark, 9 m3 chamber maintained at 220C and 60% RH, including levels of chemical vapors maintained below their respective PELs. As judged by the TCID50 of airborne MHV collected by condensation, this airborne virus was rapidly inactivated by HOCl vapor, incurring an average of 99% infectious potential loss after 16 ± 4 minutes exposure to ≤0.2 ppmv HOCl. Airborne MHV responded with a 99% loss of infectious potential in 38 ± 10 minutes of exposure to ≤0.9 ppmv H2O2; and, a 99% loss of infectious potential in 33 ± 15 minutes when exposed to a gas-phase dipropylene glycol blend ≤20 ppmv as TVOC. The juxtaposition of quantitative RT-PCR and TCID50 responses suggest that even low levels of gas-phase HOCl exposures can damage the genome of airborne coronavirus in relatively short time frames (c.a. < 5 mins).