UV-C Irradiation Effectiveness on Mpox-Virus-Contaminated Surfaces

Introduction: Mpox virus (MpoxV), an emerging zoonotic pathogen, has recently caused global concern due to increasing outbreaks beyond its traditional endemic regions. While transmission primarily occurs via close contact, fomites are also suspected of contributing. This study aims to evaluate the effectiveness of UV-C irradiation on MpoxV-contaminated surfaces. Methods: the virucidal activity of UV-C (254 nm) irradiation on MpoxV applied to plastic, glass, and stainless-steel surfaces was assessed. Using a viral stock of 2.49 × 105 TCID50/mL, the samples were exposed to increasing UV-C doses. Viral titers were quantified through TCID50 and plaque assays. Results: A UV-C dose of 6.34 mJ/cm2 achieved a >2-log reduction of viral load, below the detection limit (31.6 TCID50/mL), on all tested surfaces. EC90 values were determined as 3.33 mJ/cm2 (plastic), 0.81 mJ/cm2 (stainless steel), and 1.98 mJ/cm2 (glass). No viable virus was detectable post-treatment at these doses on plastic and stainless steel while the titer was significantly reduced on glass. Conclusions: UV-C irradiation at low doses effectively inactivated MpoxV on various fomites. These findings support UV-C as a rapid and effective environmental disinfection strategy in healthcare and community settings to prevent indirect transmission of MpoxV.