Inhibitory Effects of Copper, Brass, and Stainless Steel Surfaces on Multidrug-Resistant Microorganisms

Jung-Beom Kim1 , Jae-Kwang Kim2 , Jaewoong Lee3 , Hiun Suk Chae4 , Hae Kyung Lee2 , Yeon- Joon Park5

1Department of Food Science and Technology, Sunchon National University, Suncheon
2Department of Laboratory Medicine, Uijeongbu St.Mary’s Hospital, The Catholic University of Korea, Uijeongbu
3Incheon St.Mary’s Hospital, Incheon
4Department of Internal Medicine, Uijeongbu St. Mary’s Hospital, Uijeongbu
5Department of Laboratory Medicine, Seoul St. Mary’s Hospital, Seoul, Korea

Corresponding author : hkl@catholic.ac.kr

ABSTRACT

Background: The aim of this study was to analyze the inhibitory effects of copper, brass (78% copper, 22% tin), and stainless steel surfaces on multidrug-resistant Acinetobacter baumannii (MRAB), extended-spectrum beta-lactamase (ESBL) Escherichia coli, and carbapenem-resistant Klebsiella pneumoniae (CRKP).
Methods: MRAB, ESBL E. coli, and CRKP were isolated at Uijeongbu St.Mary’s Hospital in 2020. A. baumannii ATCC BAA-747, E. coli ATCC 25922, and K. pneumoniae ATCC 700603 were used as reference strains. The initial bacterial cell count of each inoculum was adjusted to 8 log CFU/mL using phosphate buffered saline, Copper, brass, and stainless steel plates were inoculated with 9 mL of MRAB, ESBL E. coli, and CRKP inoculum solutions. The bacterial cell count was measured from the beginning to the 20th day in an incubator maintained at 35°C.
Results: MRAB, ESBL E. coli, and CRKP isolates were not detected on the copper and brass plates after 4, 5.5, and 6.5 hours, respectively. MRAB, ESBL E. coli, and CRKP isolates were not detected on the stainless steel plate after 15, 20, and 20 days, respectively. The bactericidal effects of copper and brass were much stronger than those of stainless steel.
Conclusion: The use of copper and copper alloys should be considered to prevent cross-infection in hospitals.

Figures & Tables

Fig. 1. Inhibition effects of brass, copper, and stainless-steel surfaces on isolates and reference Acinetobacter baumannii in phosphate-buffered saline.