Antibiotic Profiles of Enteric Pathogens Isolated from Nigerian Currency Notes

Abstract

Background: Currency notes are exchangeable fomites handled by many persons daily and can potentially carry enteric pathogens on their surfaces. Infections caused by these pathogens have a global impact on public health. This study aimed to analyse the Nigerian currency notes Naira for the presence of enteric bacteria, particularly drug-resistant strains. Methods: Sixty-four Nigerian currency notes were randomly collected from various sources. Using the spread plate technique, an aliquot of 0.1ml of 10-6 dilution of each sample suspension was inoculated onto Eosin Methylene Blue agar and Hektoen Enteric agar plates. Following incubation, colonies were counted and recorded in colony-forming units per milliliter, and morphologic features were observed. Bacterial isolates were then Gram-stained, tested for motility and characterized using standard biochemical techniques. Antimicrobial profiles of bacterial isolates were determined using the Kirby-Bauer modified disc diffusion method. Results: Preliminary analysis showed that 67.2% of currency notes were contaminated. The 100 Naira notes had the highest contamination rates with bacterial mean counts of 1.22×1010 cfu/ml. Three different species of enteric bacteria were isolated. The predominant pathogens were Escherichia coli (44.2%) and Salmonella spp. (44.2%). All isolates recovered were 100% susceptible to amikacin, gentamicin, and ciprofloxacin, while 97.7% were resistant to penicillin. Escherichia coli was resistant to ampicillin (100%) and trime-thoprim-sulfamethoxazole (89.5%). Conclusion: This study showed that the Nigerian currency notes harbour enteric pathogens capable of causing serious infections to handlers. Therefore, improved hygiene practices, especially after handling currency notes, should be encouraged to prevent the spread of these pathogens.