Figure 2

Inactivation of SARS-CoV-2 BA.2 and BA.5 using the wavelength-tunable UV light source. Inactivation at (a) 200 nm (BA.2; blue), (b) 220 nm (BA.2; dark green, BA.5; light green), (c) 240 nm (BA.2; orange), and (d) 260 nm (BA.2; dark red, BA.5; light red) as a function of UV dose. Solid circles show the viral infectivity obtained by TCID₅₀ assay, and solid squares show the reduction in RNA amplification determined by qPCR, where the relative ratio to those of unexposed controls was used. Inactivation rate constants at each wavelength were determined by linear regression lines (solid line: TCID₅₀, broken line: qPCR). These linear inactivation rate constants for each wavelength are summarized in Table 1.