Assessment of Microbial and Parasitic Contamination on Currency Notes at Nnamdi Azikiwe University, Awka

Abstract

 The pervasive use of currency notes in daily transactions makes them a potential vector for microbial contamination. This issue is particularly pertinent in developing countries like Nigeria, where sanitation practices may be less stringent, and public awareness of microbial risks is often limited. This is important in light of recent outbreaks such as COVID-19. Despite this there remains a notable lack of comprehensive studies specifically addressing the extent and types of microbial contamination present on Nigerian currency. This study investigates the microbial and parasitic contamination of Nigerian currency notes, highlighting the potential health risks associated with handling money. A total of 70 currency samples were analysed, revealing presence of various protozoan parasites and bacterial pathogens. Samples for bacterial culture were prepared by swabbing currency notes with sterile saline moistened cotton swabs. Bacteria were cultured on Salmonella Shigella media, incubated, and analysed for colony characteristics. Remaining samples underwent microscopic examination for protozoan parasites after centrifugation and resuspension. Among the protozoa, Entamoeba coli was the most prevalent, found in 35.7% of samples, followed by Enterobius vermicularis (57.1%) and Entamoeba histolytica (7.1%). Notably, no significant correlation was observed between the prevalence of these parasites (P = 0.38). Bacterial contamination was also assessed, with Klebsiella spp. detected in 50% of samples, while Escherichia coli and Proteus spp. were each found in 25% of the samples. Again, no significant association was noted among the bacterial contaminants (P = 0.377). The study further differentiated between polymer and paper notes, revealing that polymer notes (10 to 50 naira) were free from contamination, while paper notes exhibited varying contamination rates, with 100-naira notes showing 35.7% contamination. Mutilated notes had highest contamination level at 22.97±4.51%, compared to clean and dirty notes. Overall, the findings underscore the necessity for improved hygiene practices regarding currency handling to mitigate potential health risks.