A Continuously Active Antimicrobial Surface Coating Reduces Bioburden in a Healthcare Setting

Abstract

Background: It is well known that contaminated surfaces contribute to the transmission of pathogens in healthcare settings, necessitating the need for antimicrobial strategies beyond routine cleaning with momentary disinfectants. A recent publication demonstrated that application of a novel, continuously active antimicrobial surface coating in ICUs resulted in the reduction of healthcare-associated infections. Objective: We determined the general microbial bioburden and incidence of relevant pathogens present in patient rooms at 2 metropolitan hospitals before and after application of a continuously active antimicrobial surface coating. Methods: A continuously active antimicrobial surface coating was applied to patient rooms in intensive care units (ICUs) twice over an 18-month period and in non-ICUs twice over a 6-month study period. The environmental bioburden was assessed 8–16 weeks after each treatment. A 100-cm² area was swabbed from frequently touched areas in patient rooms: patient chair arm rest, bed rail, TV remote, and backsplash behind the sink. The total aerobic bacteria count was determined for each location by enumeration on tryptic soy agar (TSA); the geometric mean was used to compare bioburden before and after treatment. Each sample was also plated on selective agar for carbapenem-resistant Enterobacteriaceae (CRE), vancomycin-resistant enterococci (VRE), methicillin-resistant Staphylococcus aureus (MRSA), and Clostridioides difficile to determine whether pathogens were present. Pathogen incidence was calculated as the percentage of total sites positive for at least 1 of the 4 target organisms. Results: Before application of the antimicrobial coating, total aerobic bacteria counts in ICUs were >1,500 CFU/100 cm², and at least 30% of the sites were positive for a target pathogen (ie, CRE, VRE, MRSA or C. difficile). In non-ICUs, the bioburden before treatment was at least 500 CFU/100 cm², with >50% of sites being contaminated with a pathogen. After successive applications of the surface coating, total aerobic bacteria were reduced by >80% in the ICUs and >40% in the non-ICUs. Similarly, the incidence of pathogen-positive sites was reduced by at least 50% in both ICUs and non-ICUs. Conclusions: The use of a continuously active antimicrobial surface coating provides a significant (P < .01) and sustained reduction in aerobic bacteria while also reducing the occurrence of epidemiologically important pathogens on frequently touched surfaces in patient rooms. These findings support the use of novel antimicrobial technologies as an additional layer of protection against the transmission of potentially harmful bacteria from contaminated surfaces to patients.

Funding: Allied BioScience provided Funding: for this study.

Disclosures: Valerie Beck reports salary from Allied BioScience.