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Aims This study evaluated the residual efficacy of commercially available antimicrobial coatings or films against severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) on non‐porous surfaces. Methods and Results Products were applied to stainless steel or ABS plastic coupons and dried overnight. Coupons were inoculated with SARS‐CoV‐2 in the presence of 5% soil load. Recovered infectious SARS‐CoV‐2 was quantified by TCID50 assay. Tested product efficacies ranged from <1.0 to >3.0 log10 reduction at a 2‐h contact time. The log10 reduction in recovered infectious SARS‐CoV‐2 ranged from 0.44 to 3 log10 reduction on stainless steel and 0.25 to >1.67 log10 on ABS plastic. The most effective products tested contained varying concentrations (0.5%–1.3%) of the same active ingredient: 3‐(trihydroxysilyl) propyldimethyloctadecyl ammonium chloride. Products formulated with other quaternary ammonium compounds were less effective against SARS‐CoV‐2 in this test. Conclusions The residual antimicrobial products tested showed varied effectiveness against SARS‐CoV‐2 as a function of product tested. Several products were identified as efficacious against SARS‐CoV‐2 on both stainless steel and ABS plastic surfaces under the conditions evaluated. Differences in observed efficacy may be due to variation in active ingredient formulation; efficacy is, therefore, difficult to predict based upon listed active ingredient and its concentration. Significance and Impact This study highlights the formulation‐specific efficacy of several products against SARS‐CoV‐2 and may inform future development of residual antiviral products for use on non‐porous surfaces. The identification of antimicrobial coatings or films showing promise to inactivate SARS‐CoV‐2 suggests that these products may be worth future testing and consideration.

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Aims This study aimed to provide operationally relevant severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) surface disinfection efficacy information. Methods and Results Three EPA-registered disinfectants (Vital Oxide, Peroxide, and Clorox Total 360) and one antimicrobial formulation (CDC bleach) were evaluated against SARS-CoV-2 on material coupons and were tested using Spray (no touch with contact time) and Spray & Wipe (wipe immediately post-application) methods immediately and 2 h post-contamination. Efficacy was evaluated for infectious virus, with a subset tested for viral RNA (vRNA) recovery. Efficacy varied by method, disinfectant, and material. CDC bleach solution showed low efficacy against SARS-CoV-2 (log reduction &lt; 1.7), unless applied via Spray & Wipe. Additionally, mechanical wiping increased the efficacy of treatments against SARS-CoV-2. The recovery of vRNA post-disinfection suggested that vRNA may overestimate infectious virus remaining. Conclusions Efficacy depends on surface material, chemical, and disinfection procedure, and suggests that mechanical wiping alone has some efficacy at removing SARS-CoV-2 from surfaces. We observed that disinfectant treatment biased the recovery of vRNA over infectious virus. Significance and Impact of Study These data are useful for developing effective, real-world disinfection procedures, and inform public health experts on the utility of PCR-based surveillance approaches.

Efficacy of cleaning methods against SARS-CoV-2 suspended in either 5% soil load (SARS-soil) or simulated saliva (SARS-SS) were evaluated immediately (hydrated virus, T0) or 2 hours post-contamination (dried virus, T2). Hard water dampened wiping (DW) of surfaces, resulted in 1.77-3.91 log reduction (T0) or 0.93-2.41 log reduction (T2). Incorporating surface pre-wetting by spraying with a detergent solution (D+DW) or hard water (W+DW) just prior to dampened wiping did not unilaterally increase efficacy against infectious SARS-CoV-2, however the effect was nuanced with respect to surface, viral matrix, and time. Cleaning efficacy on porous surfaces (seat fabric, SF) was low. W+DW on stainless steel (SS) was as effective as D+DW for all conditions except SARS-soil at T2 on SS. DW was the only method which consistently resulted in &gt;3-log reduction of hydrated (T0) SARS-CoV-2 on SS and ABS plastic. These results suggest that wiping with a hard water dampened wipe can reduce infectious virus on hard non-porous surfaces. Pre-wetting surfaces with surfactants did not significantly increase efficacy for the conditions tested. Surface material, presence or absence of pre-wetting and time post-contamination affect efficacy of cleaning methods.