Microbial Spectrum and Viability of Bacterial Contaminants on Banknotes

Reuben Essel Arhin; Henry Kwadwo Hackman; Barry Kojo Whyte; Florence Adwoa Ayirezang; Bright Kojo Azumah; Phyllis Naa Yarley Otu; Mary-Magdalene Osei; Michael Olu-Taiwo

doi:10.5455/EJMID.20240908103128

Abstract
Background & Aim: Banknotes are potential fomites for transmission of infection in different environments between people of different health status, hygiene practices, and health awareness. The aim of this study was to determine the spectrum of bacterial contaminants on Ghanaian banknotes and their ability to remain viable.
Methods: Different denominations were collected for physical examination. The viability of bacteria present on each banknote was determined over a storage period by culturing, isolating, and biochemical identification. Positive-culture banknotes were analyzed every 3 days for a period of 12 days. The antimicrobial resistance of the selected bacteria isolates was determined by the Kirby-Bauer disc diffusion test.
Results: The banknotes in mint (4%), fairly clean (54%), and dirty (42%) physical conditions had print ages ranging from 23 to 72 months. Eighty-nine isolates of 6 species comprising 0 to 3 species per banknote were identified. These were Citrobacter sp. 32 (36.0 %), Bacillus sp. 25 (27.2 %), Staphylococcus aureus 16 (17.4 %), Citrobacter koseri 11 (12 %), Enterobacter sp. 3 (3.3 %), and Escherichia coli 2 (2.2 %). The median observed survival time was six days for 5 species.
Conclusion: A high prevalence of pathogens may occur among bacterial contaminants on banknotes of different physical conditions, denominations, ages, and from different sampling sites. These can remain viable for more than 6 days and may potentially contribute to the transmission of antimicrobial resistant diseases.

Key words: Contamination, Denomination, Bacteria, Resistance, Isolation, Identification