انتشار التلوث البكتيري على العملات الورقية الجديدة في مدينة تعز، اليمن

Abstract

Background: Paper currency is widely circulated and handled daily, serving as a potential vehicle for microbial transmission. In Yemen, particularly Taiz city, there is limited information regarding the bacterial contamination of newly issued banknotes, which poses a potential public health concern. Aim: This study aimed to evaluate the prevalence and types of bacterial contamination on new Yemeni banknotes circulating in Taiz city. Methods: A cross-sectional study was conducted from October 2024 to January 2025. Forty-eight samples of new Yemeni banknotes across three denominations (200, 500, and 1000 Yemeni Rials) were collected from eight sources, including cash wallets, buses, hospitals, meat markets, university staff, cashiers, laboratories, and school cafeterias. Bacterial load was quantified using standard serial dilution and nutrient agar culture methods, while pathogenic bacteria were identified through selective media, Gram staining, and biochemical tests. Data were analyzed using SPSS version 21. Results: All tested banknotes were contaminated with bacteria. The highest microbial load was observed in the 500 denominations, followed by 200 and 1000 denominations. Among the sources, school cafeterias showed the highest contamination, whereas hospital samples were the least contaminated. The predominant pathogenic bacteria identified included Staphylococcus aureus (30%), Streptococcus viridians (18.3%), Escherichia coli (13.3%), Enterococcus faecalis (11.7%), and Staphylococcus epidermidis (10%). Less frequently isolated species included Bacillus subtilis, Klebsiella spp., Staphylococcus saprophyticus, and Neisseria meningitidis. Conclusion: New Yemeni banknotes in Taiz city are extensively contaminated with both commensal and pathogenic bacteria, posing a potential risk for disease transmission. Higher contamination was associated with lower denominations and certain handling sources, highlighting the need for improved hygiene practices. Recommendations: Regular hand hygiene, use of antimicrobial materials for banknotes, and public awareness regarding safe handling of currency are crucial to mitigate bacterial transmission from banknotes.