Association of multidrug resistant <i>Staphylococcus aureus</i> and <i>Escherichia coli</i> with specific naira denominations

Abstract

Currency serves as a global tool for commerce but is notorious for its association with potentially pathogenic bacteria. This has been further complicated by the growing evolution and emergence of drug resistance among bacteria, with various currencies associated with multidrug resistant (MDR) strains. This could be a silent factor in the current scourge of multidrug resistance. This study therefore set out to explore the presence of multidrug resistance Escherichia coli and Staphylococcus aureus in specific denominations of Naira, the Nigerian currency in Rivers State, Nigeria. A total of 50 naira notes comprised of two commonly used denominations (₦50 and ₦100) made up of two different materials (polymer and paper) were analyzed for microbial load, presence of key bacteria and drug resistance using standard tests. Results of the study revealed high bacterial loads with Log10 values ranging from 4.52 to 5.39 for the ₦100 notes and 4.52 to 5.31 for ₦50 notes. Samples had a higher occurrence of S. aureus (26) than E. coli (8). These isolates were associated with very high rates of resistance though the Gram-positive organisms were more resistant. Both S. aureus and E. coli had high rates of MDR (96.2% and 100% respectively). This study reveals an association of the Nigerian currency, Naira, with a variety of drug resistant bacteria and high levels of multidrug resistance in key pathogens and primarily underscores the need for continuous hand washing as the first key step in disease prevention.