Bacterial contamination of Nigerian currency notes circulating within selected markets in Kaduna Metropolis

A study was carried out with the aim to assess the bacterial contamination of Nigerian currency notes circulating within selected markets in Kaduna Metropolis. A total of 80 samples of Nigerian currency notes of different denominations were randomly collected from Sabo, Kakuri, Kawo, Dattawa, U/rimi, Kasuwar Sati, Nassarawa, Chechenia, Kasuwar barci and Kasuwar Laraba markets in sterilized polythene bags The mean bacterial counts of the different currency notes were determined using standard microbiological methods. The types of bacteria associated with the currency notes and their frequency of occurrence were also determined using standard methods. The result of the study showed that lower denomination currencies had higher microbial loads, 22.65×104 ± 0.22×104 CFU/g for N100, 26.55×104 ± 0.45×104 CFU/g for N50, 20.95×104 ± 0.26×104 CFU/g for N20, 21.75×104 ± 0.35×104 CFU/g for N10 and 21.75×104 ± 0.12×104 CFU/g for N5 which were mostly obtained from Kakuri, Sabo, Nasarawa, and U/Rimi markets The species of bacteria isolated from the currencies were Staphylococcus aureus (52.2%), Escherichia coli (31.3%), Salmonella species (11.9%), and Proteus species (4.5%). Staphylococcus aureus was the most predominant bacteria isolated. This study revealed that currency notes collected from the markets within Kaduna Metropolis, were highly contaminated with different pathogenic bacteria thus, calls for public awareness on the potential risks associated with poor handling of currency notes at all levels. Key words: Bacterial contamination, currency notes, selected markets, Kaduna Metropolis