Paper Money and Coins as Potential Vectors of Transmissible Disease

Emmanouil Angelakis; Esam I Azhar; Fehmida Bibi; Muhammad Yasir; Ahmed K Al-Ghamdi; Ahmad M Ashshi; Adel G Elshemi; Didier Raoult


Future Microbiol. 2014;9(2):249-261. 

In This Article


Few studies have examined the contamination of coinage, and copper (Cu) seems to be a limiting factor for bacterial survival on coins.[28] As a result, coins have been found to carry opportunistic bacterial pathogens, but they exhibit a lower bacterial load than paper currency.[28]


Coins have been shown to carry opportunistic pathogens, such as a variety of species of the genera Staphylococcus, Bacillus, and Corynebacterium (Table 1).[28,31] Abrams and Waterman found that 13% of the coins collected from laboratory personnel were contaminated by potential pathogens, such as S. aureus, Klebsiella sp., P. aeruginosa and P. mirabilis.[6] Many different species were also isolated on coins from Kenya, and the average bacterial content on the coins ranged from 2.3 to 25 × 103 CFU (Table 1).[22] Most commonly, Gram-positive staphylococci and micrococci were isolated from EU¢50 coins collected in Germany and Portugal (Table 1).[28] The absence of streptococci isolates from coins probably suggests a high sensitivity of these bacteria to metallic Cu.[28] In a recent study on the bacterial flora collected from coins from 17 countries, all of the isolates from coins were Gram-positive strains, with the majority belonging to the genera Bacillus (40%) and Staphylococcus (28%) (Figure 3).[31] Recently, Pseudomonas psychrotolerans and Roseomonas pecuniae were isolated from EU¢50 coins Cu-alloy coins.[32,33] Multiple genes that are potentially involved in Cu resistance were identified in these bacteria.[32]

Figure 3.

Infectious agents isolated from coins from different countries.

Other Agents

Yeast and fungi were isolated from coins collected from laboratory personnel.[6] More recently, Penicillium spp, Aspergillus niger, Fusarium, Rhizopus, Altenaria spp, Candida spp. and Cryptococcus were isolated from Kenyan coins.[22]