Ultraviolet-Based Viral Inactivation: A Critical Examination of Current Research

Ultraviolet (UV) radiation has emerged as a powerful, non-chemical disinfection method, gaining significant attention for its ability to inactivate pathogenic microorganisms, particularly viruses, amid global public health challenges such as the COVID-19 pandemic. This study provides a comprehensive analysis of UV-based viral inactivation technologies, with a focus on ultraviolet germicidal irradiation (UVGI) using the UV-C spectrum (200-280 nm). It explores the fundamental physical principles of UV radiation, the photochemical mechanisms disrupting microbial DNA and RNA, and the critical parameters influencing disinfection efficacy, including UV dose, irradiance, wavelength, exposure time, and environmental conditions. Theoretical frameworks are supported by calculations and experimental data to evaluate the impact of material properties, surface characteristics, and atmospheric factors on UV performance. The study critically assesses UVGI applications in diverse settings, such as healthcare facilities, public spaces, ventilation systems, and water treatment, while addressing safety considerations, technological limitations, and potential health risks associated with UV exposure. By synthesizing theoretical insights, experimental findings, and a detailed review of UV sensitivity across various pathogens, including SARS-CoV-2 and other coronaviruses, this work highlights the high susceptibility of viral pathogens to UV-C radiation. It also examines the implications of RNA mutations on UV efficacy and provides estimated inactivation doses for a range of microorganisms. These findings underscore the potential of UV-based technologies as a cornerstone of modern infection control strategies, offering insights into optimizing system design and implementation for effective microbial inactivation while ensuring safety and scalability in real-world applications.