Multidrug-resistant Bacterial Contamination of Point-of-Sale (POS) Machines and Associated Risk Factors in Kano Metropolis, Nigeria

Abstract

Background: The Point-of-Sale (POS) machine is a portable, computerized device widely used to facilitate financial transactions. Despite its convenience, POS machines have been reported to harbor various microorganisms due to frequent handling by multiple users, thereby posing a potential risk of infection. This concern is heightened by the increasing prevalence of multidrug-resistant bacteria, which limits the effectiveness of commonly used antibiotics and represents a significant public health threat. Understanding the extent of microbial contamination and the associated risk factors of POS machines is therefore critical, particularly in urban settings such as Kano Metropolis, Nigeria. Objectives: This study assessed the prevalence of MDR bacterial contamination on POS machines in Kano Metropolis and identified associated risk factors. Methods: A cross-sectional mixed-methods design was employed. Swab samples were collected from 50 POS machines across various sectors, and bacterial isolates were identified using standard microbiological techniques. Antibiotic susceptibility testing followed CLSI guidelines. A structured questionnaire was administered to 100 vendors and users to evaluate hygiene practices and awareness of MDR bacteria. Data were analyzed using descriptive statistics and logistic regression to identify contamination risk factors. Results: All sampled POS machines (100%) were contaminated. Twenty bacterial isolates were recovered, including Bacillus spp. (30%), Staphylococcus aureus (25%), Klebsiella spp. (15%), Pseudomonas aeruginosa (10%), coagulase-negative staphylococci (10%), Enterobacter spp. (5%), and Proteus spp. (5%). Multidrug resistance was observed in 60% of isolates. Poor cleaning and disinfection practices and limited awareness of MDR bacteria among users were significantly associated with contamination. Conclusion: POS machines in Kano Metropolis are heavily contaminated with MDR bacteria. Public health interventions, including targeted hygiene education, routine cleaning protocols, and surveillance of antimicrobial resistance on frequently handled devices, are urgently needed to reduce the risk of pathogen transmission.