Evaluation of the Efficacy of UV-C Radiation in Eliminating Microorganisms of Special Epidemiological Importance from Touch Surfaces under Laboratory Conditions and in the Hospital Environment

Anna Różańska; Monika Walkowicz; Małgorzata Bulanda; Tomasz Kasperski; Edyta Synowiec; Piotr Osuch; Agnieszka Chmielarczyk

doi:10.3390/healthcare11233096

Evaluation of the Efficacy of UV-C Radiation in Eliminating Microorganisms of Special Epidemiological Importance from Touch Surfaces under Laboratory Conditions and in the Hospital Environment

Healthcare (Basel). 2023 Dec 4;11(23):3096. doi: 10.3390/healthcare11233096.

Authors

Anna Różańska¹, Monika Walkowicz², Małgorzata Bulanda¹, Tomasz Kasperski¹, Edyta Synowiec³, Piotr Osuch², Agnieszka Chmielarczyk¹

Affiliations

¹ Department of Microbiology, Faculty of Medicine, Jagiellonian University Medical College, Czysta str. 18, 31-121 Kraków, Poland.
² Department of Metal Working and Physical Metallurgy of Non-Ferrous Metals, Faculty of Non-Ferrous Metals, AGH University of Krakow, al. A. Mickiewicza 30, 30-059 Krakow, Poland.
³ John Paul II Specialistic Hospital, Prądnicka 80, 31-202 Kraków, Poland.

Abstract

Introduction: Healthcare-associated infections in the post-pandemic era are as important as they were before COVID-19. The dominant route of transmission of microorganisms in health care units is the contact route, for which hand hygiene is of cardinal importance, but also effective disinfection of touch surfaces. Traditional disinfection based on chemical compounds is sensitive to human errors. Therefore, a valuable supplement to it can be contactless disinfection methods, including the use of UV-C. The aim of the study was to assess the effectiveness of UV-C radiation in eliminating selected, most important pathogens of particular epidemic importance from surfaces made of various materials: stainless steel, plastic and glass, most often found in hospital conditions.

Material and method: In laboratory conditions, the study was conducted using bacterial strains of great epidemiological importance and Candida auris. In hospital wards, samples were taken before and after disinfection for comparisons of the composition and quantity of bacteria. In laboratory conditions, carriers made of steel, plastic and glass were contaminated with a bacterial suspension with a density of approx. 0.5 McFarland, and then the density of persistent microorganisms was assessed after 10 min of UV-C irradiation.

Results: The high effectiveness of UV-C radiation in eliminating bacteria contaminating touch surfaces in hospital wards and in laboratory conditions has been confirmed. The elimination efficiency in laboratory conditions was slightly lower (statistically insignificant) on the plastic surface, which is probably related to subtle differences in the thickness of the contaminating layer. Hydrophobic properties and the smallest suspension diameter were confirmed for the tested plastic carriers.

Conclusions: UV-C disinfection is a desirable element to support traditional, chemical methods of disinfection in hospital conditions, effective against multidrug-resistant bacteria and C. auris.

Keywords: Candida auris; ESKAPE; UV-C disinfection; infection control.

Grants and funding

The research was founded by the cooperation agreement between Jagiellonian University Medical College and Eco-Light Bio Safety.