Evaluation of surface disinfection methods to inactivate the beta coronavirus Murine Hepatitis Virus

Abstract

The list of EPA-approved disinfectants for coronavirus features many products for use on hard, non-porous materials. There are significantly fewer products registered for use on porous materials. Further, many common, high-touch surfaces fall in between non-porous materials such as glass and porous materials such as soft fabrics. The objective of this study was to assess the efficacy of selected commercially available disinfectant products against coronaviruses on common, high-touch surfaces. Four disinfectants (Clorox Total 360, Bleach solution, Vital Oxide, and Peroxide Multi-Surface Cleaner) were evaluated against Murine Hepatitis Virus A59 (MHV) as a surrogate coronavirus for SARS-CoV-2. MHV in cell culture medium was inoculated onto four materials: stainless steel, latex-painted drywall tape, Styrene Butadiene rubber (rubber), and bus seat fabric. Immediately (T0) or 2-hr (T2) post-inoculation, disinfectants were applied by trigger-pull or electrostatic sprayer and either held for recommended contact times (Spray only) or immediately wiped (Spray and Wipe). Recovered infectious MHV was quantified by median tissue culture infectious dose assay. Bleach solution, Clorox Total 360, and Vital Oxide were all effective (>3-log₁₀ reduction or complete kill of infectious virus) with both the Spray Only and Spray and Wipe methods on stainless steel, rubber, and painted drywall tape when used at recommended contact times at both T0 and T2 hr. Multi-Surface Cleaner unexpectedly showed limited efficacy against MHV on stainless steel within the recommended contact time; however, it showed increased (2.3 times greater efficacy) when used in the Spray and Wipe method compared to Spray Only. The only products to achieve a 3-log₁₀ reduction on fabric were Vital Oxide and Clorox Total 360; however, the efficacy of Vital Oxide against MHV on fabric was reduced to below 3-log₁₀ when applied by an electrostatic sprayer compared to a trigger-pull sprayer. This study highlights the importance of considering the material, product, and application method when developing a disinfection strategy for coronaviruses on high-touch surfaces.

Keywords:

• Coronavirus
• disinfection
• efficacy

Acknowledgments

We thank members of the U.S. Environmental Protection Agency Office of Research and Development for helpful discussions and guidance on study objectives. We also thank Clint Fleshman, David Glasbrenner, Nola Bliss, and Amy Hill at Battelle Memorial Institute for assistance with experimental set up and method development.

Author contributions

All authors listed contributed to this work and are entitled to authorship. SWN, DB, NFR, and JMG conducted cytotoxicity assays, cell cultures, and performed laboratory efforts supporting protocol development. RLH, SWN, DB, DJL, NFR, GAF, and JMG conducted all product efficacy testing at Battelle Memorial Institute. RRJ, MWC, SDL, MJS, SPR, and MWH designed the study and assisted with manuscript preparation. MWH and RLH coordinated and implemented the study, developed protocols, analyzed the data, and drafted the manuscript.

Conflict of interest statement

Neither Battelle nor the EPA manufacture or provide the products or materials described herein, nor plan to manufacture or provide these products in the future.

Data availability

All data are publicly available at data.gov.

Additional information

Funding

The research described in this article has been funded wholly or in part by the U.S. Environmental Protection Agency under contract number EP-C-16-014/Task Order 68HERC20F0220 to Battelle Memorial Institute. It has been subjected to review by the EPA’s Office of Research and Development and approved for publication. Approval does not signify that the contents reflect the views of the Agency, nor does mention of trade names or commercial products constitute endorsement or recommendation for use.