Fig 1.
Schematic illustration of the test chamber.
The composition of the chamber is described in detail in the Materials and methods.
Fig 2.
Flow diagram of the virus inactivation experiment.
A detailed procedure is described in the Materials and methods.
Fig 3.
Inactivation of viruses by the dry fogging of disinfectants.
Changes in the viral infectious titers (TCID50 values) of SARS-CoV-2 (A and C) and influenza A virus (B and D) upon dry fogging with hypochlorous acid solution (HAS) (A and B), hydrogen peroxide solution (H2O2) (C and D), or distilled water (DW) (A, B, C, and D) were evaluated, as described in the Materials and methods. Horizontal dotted lines in the graphs show the detection limit of the viral titer. *P < 0.0001 compared with DW using a two-way ANOVA. n.s., not significant. Each data point represents the average and standard deviation obtained from more than three repeated experiments.
Fig 4.
Relationship between dry fogged disinfectant concentrations and concentrations of disinfectants trapped in 20 ml of distilled water in Petri dishes.
The dry fogging of hypochlorous acid solution (A) or hydrogen peroxide solution (B) was performed as described in the Materials and methods. The concentrations of free available chlorine FAC (C) and hydrogen peroxide (H2O2) per unit fogging time (D) were calculated and plotted. R squared (R2) values were estimated using a non-linear regression (curve fit) analysis and reported on the graphs (A and B). In addition, R2 values, equations, and p values were estimated using a simple linear regression analysis and reported on the graphs (C and D).
Fig 5.
The relationship between virucidal effects of a disinfectant and the CT value.
Changes in the viral infectious titers (TCID50 values) of SARS-CoV-2 (A and C) and influenza A virus (B and D) upon dry fogging with hypochlorous acid solution (A and B) or hydrogen peroxide solution (C and D) were evaluated, as described in the Materials and methods. The CT value of a dry fogged disinfectant was calculated, and a scatter plot was created from each dataset of the viral infectious titer and CT value for the combination of the virus and disinfectant. R squared (R2) values, equations, and p values were estimated using a simple linear regression analysis and reported on the graphs. Horizontal dotted lines in the graphs show the detection limit of the viral titer.
Fig 6.
Effects of saliva on the inactivation of SARS-CoV-2 and influenza A virus by the dry fogging of disinfectants.
SARS-CoV-2 (A and C) or influenza A virus (B and D) was mixed with artificial saliva or PBS, and air-dried. Changes in the viral infectious titers (TCID50 values) upon dry fogging with hypochlorous acid solution (HAS) (A and B) or hydrogen peroxide solution were then evaluated, as described in the Materials and methods. Horizontal dotted lines in the graphs show the detection limit of the viral titer. n.s., not significant between artificial saliva- and PBS-containing samples using an unpaired t-test. Each data point represents the average and standard deviation obtained from two repeated experiments.