A Microbiological study of Bacteria on circulating currency used in Baghdad- Iraq

A Paper currency note is widely exchanged for different purpose in worldwide and the first time be developed in China. these banknotes may acting as environmental vehicle for the transmission of potential pathogenic microorganisms specially bacteria, which depend of individual who living in poor hygienic conditions and having unhygienic habits( improper hand washing after using the toilet, counting paper notes using saliva, coughing and sneezing on hands then exchanging money, and placement or storage of paper notes on dirty surfaces),which may leads to contaminate the notes with bacteria, then will act as a bridge delivering bacteria to another hands of the next user , then to all the community persons. Hence the aim of this study is isolating the bacteria then identify their types, which may contaminate different circulating and new uncirculated Iraqi currency paper.This study was done in Microbiology lab /Department of Medical Laboratories Techniques at AL-Hikma University College, Baghdad- Iraq, during the period started from December 2024 until February 2025. It was designed to find out the most common bacteria in two hundred thirty-five sterile swab samples taken from different denominations circulating and new uncirculated currency distributed in (250, 500, 1000, 5000, 10000,25000,50000) Iraqi dinar from different locations and different occupational groups in Baghdad city. From each banknote (235) we took one sterile swab with normal saline for bacterial culture on enrichment and selective media then incubated under aerobic condition, at 24-48 hours, next diagnosed and identification by Epi system, our results Tow hundred twenty-eight bacterial isolates represented by (60)G-ve bacterial isolates(Pseudomonas, Proteus, E. coli, Klebsiella) and 168 G+ve bacterial isolates(Staphylococcus aureus and (CoNS) also Streptococcus sp.) ,from circulating and new uncirculated currency in Iraq. The current study concluded that Iraqi currency act as a significant vector for the transmission of Gram positive and negative pathogenic bacteria and may be considered as a source of many infectious diseases. Generally, the personal hygiene of Iraqi individual is very low and that posing a public health threat to community. Based on this study results, to reduce the bacterial on Iraqi currency through: promoting the use of cashless payment methods(Electronic payment card), implementing regular disinfecting measures for currency , and enhancing personal hygiene practices among community individuals starting from the primary school stages and so on through applied and improve programs to how banknotes used , and increased consciousness of the risks and methods of transmission of microorganisms especially pathogenic bacteria.