Use of a protective antimicrobial coating to reduce the microbial load in public transportation – a real-scenario study

Abstract

BACKGROUND AND AIM: The need to disinfect and sanitise private or public spaces, as a consequence of the pandemic caused by the Sars-Cov-2 virus, has raised new questions and demands in the sanitary field, including new cleaning and sanitising practices. Public transportation is one of the sectors most impacted by this new reality. The greatest cause for concern in terms of infection risk is related to the high flow and close contact between individuals and the constant sharing of surfaces. In fact, human pathogens have been detected on surfaces highly touched in public transportation. In this study, the antimicrobial activity of the Progen Guard Technology 24H coating (CTEQ - Indústria Química, Portugal|) on surfaces of public buses during their normal daily operating period was investigated. METHODS: Three different buses circulating in Santo Tirso (north of Porto Metropolitan Area, Portugal) between October and December 2020 were part of this study. Swab samples were taken from three surfaces treated with the product and from three untreated surfaces (treated and untreated doorbell buttons, ceiling-mounted handles, stanchions) immediately after product application and every 24 h for 4 days. Immediately after collection, samples were transported to the laboratory and enumeration of total aerobic microorganisms at 30 ºC was performed. RESULTS:For the analyzed parameter and the investigated surfaces, it was concluded that the application of Progen Guard Technology 24H significantly reduces the total microbial load on surfaces immediately after application (86.3% to 98.8%) and for at least 24 hours (72.7% to 98.7%) in a real context - naturally contaminated surfaces and non-controlled conditions. CONCLUSIONS:These are promising results concerning the prevention of the spread of contaminants in public spaces. This antimicrobial coating deserves to be further investigated in other real-life scenarios where environmental microbial contamination is a cause for concern (e.g., healthcare settings). KEYWORDS: Non-chemical stressors, microbes, Infectious diseases