Antibiotic Resistance and Public Health Perspective of Bacterial Contamination of Nigerian Currency

Abstract

Nigerian bank notes like other currencies in the world pass through different hands and have been implicated in the carriage of medically important pathogens. This study was undertaken to determine the types of bacteria present on Nigerian currency in Ile-Ife, Osun State, with a view to determining the potential of naira notes as environmental vehicle for the transmission of potential pathogenic bacteria.  Standard microbiological methods were used to isolate, characterize and identify the bacterial isolates from different banknotes. Disc diffusion method was used to determine the sensitivity of the isolates to ten antibiotics. Representative multiple antibiotic resistant isolates were profiled for plasmid deoxyribonucleic acid (DNA). A total of three hundred and five comprising 216 Gram positive and 89 Gram negative bacteria were isolated from two hundred and five bank notes sampled; naira in mint condition was used as control. Thirteen bacterial genera namely Bacillus, Corynebacterium, Staphylococcus, Lactobacillus, Micrococcus, Aeromonas, Citrobacter, Edwardsiella, Klebsiella, Moraxiella, Pseudomonas, Enterobacter and Proteus were recovered. Resistance to antibiotics was generally high and varied among the isolates. Resistance ranged from 18.18% to 100% in Gram negative bacteria and 26.6% to 100% in Gram positive isolates. Enterobacter sp. and Edwardsiella sp. recovered were 100% resistant to all the antibiotics except septrin. All the isolates were resistant to more than one antibiotic. Multiple antibiotic resistant isolates harboured plasmids of various sizes, ranging from 1,356 bp to 17,367 bp in Gram- positive bacteria and 1815 to 23130 bp in Gram negative isolates. Nigerian currency harboured different types of multiple antibiotic resistant bacteria which can be implicated in human infections; hence constituting a potential public health hazard.

Keywords: bacteria, multiple antibiotic resistance, currency, plasmids, pathogens, mint