Currency notes are essential components of our day-to-day activities as they play great roles in our transactions. However, they have continued to serve as media of exchange of pathogenic microorganisms and parasites. The naira note has been greatly mishandled by Nigerians over the years, and this has led to the circulation of dirty, contaminated, and mutilated notes. This systematic review was carried-out to provide an up-to-date summary of the public health risks associated with contaminated naira notes. This systematic review was conducted and reported in conformation with the Preferred Reporting Items for Systematic Reviews and Meta-analyses Protocols 2015 (PRISMA-P) statements and checklists. Databases (PubMed, AJOL, and Google Scholar) were searched for published articles on the microbial and parasitic contamination of naira notes. A total of 26 studies were analyzed for this review. The studies majorly reported high microbial contamination in lower denomination naira notes (N10 and N100). The pathogens from naira notes reported in the studies include Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumonia, Salmonella typhi, Vibrio cholera, Aspergillus niger, and Blastomyces dermatitidis. Eggs and cysts of Ascaris lumbricoides eggs, hookworm, lice of the genus Pediculus humanus corporis, Enterobius vermicularis, flagellates, and Entamoeba histolytica were reported in the studies. A high degree of resistance of bacterial pathogens from naira notes to commonly used antibiotics was also observed in this study. Currency notes serve as fomites for the transfer of pathogenic microorganisms and parasites. Most of the organisms reported in this study have been implicated in human infections including food-borne infections, urinary tract infections, and respiratory infections. Good hygiene and proper education of Nigerians on the public health risks posed by mishandling naira notes should be done to reduce the spread of pathogens and parasites through naira notes.

Background: Carbapenems are drugs of last resort and resistance to them is considered a great public health threat, especially in notorious nosocomial pathogens like Acinetobacter baumannii and Pseudomonas aeruginosa. In this study, we aimed to determine the prevalence of carbapenem resistance in A. baumannii and P. aeruginosa infections in Sub Saharan Africa. Methods: Databases (PubMed, Scopus, Web of Science, and African Journal Online) were systematically searched following the Preferred Reporting Items for Systematic review and meta analysis protocols (PRISMA-P) 2020 statements for articles reporting carbapenem-resistant Acinetobacter baumannii (CRAB) and carbapenem-resistant Pseudomonas aeruginosa (CRPA) prevalence between 2012 and 2022. Pooled prevalence was determined with the random effect model in R. Results: A total of 47 articles were scanned for eligibility, among which 25 (14 for carbapenem-resistant A. baumanii and 11 for carbapenem-resistant P. aeruginosa) were included in the study after fulfilling the eligibility criteria. The pooled prevalence of CRPA in the present study was estimated at 8% (95% CI; 0.02 to 0.17; I2=98%; P <0.01). There was high heterogeneity (Q=591.71, I2=98.9%; P<0.0001). The pooled prevalence of CRAB in the present study was estimated at 20% (95% CI; 0.04 to 0.43; I2=99%; P <0.01). There was high heterogeneity (Q=1452.57, I2=99%; P<0.0001). Carbapenem-resistant A. baumannii prevalence based on sample source gave estimates of 24% (95% CI; 6 to 49; I2=99%; P<0.01). The carbapenamse genes commonly isolated from A. baumanii in this study include blaOXA23, blaOXA48, blaGES., blaNDM, blaVIM, , blaOXA24, blaOXA58, blaOXA51, blaSIM-1, blaOXA40, blaOXA66, blaOXA69, blaOXA91, with blaOXA23 and blaVIM being the most common. On the other hand, blaNDM, blaVIM, blaIMP,, blaOXA48, blaOXA51, blaSIM-1, blaOXA181, blaKPC, blaOXA23, blaOXA50 were the commonly isolated carbapenemase genes in P. aeruginosa, among which blaVIM and blaNDM genes were the most frequently isolated. Conclusion: Surveillance of drug-resistant pathogens in sub-Saharan Africa is essential in reducing the disease burden in the region and this study has shown that the region has significantly high multidrug resistant pathogen prevalence. This is a wakeup call for policymakers to put in place measures to reduce the spread of these critical priority pathogens.