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To the authors' knowledge, the role of restaurant menus as a vehicle for pathogens has not been explored. Menus, however, can pose as a vector for bacterial contamination and transfer. Sampling menus from two restaurants in the Houston, Texas, area showed the presence of up to 100 CFU/cm2 aerobic bacteria. Follow-up studies designed to investigate the ability of Salmonella and E. coli to persist on paper and laminated menus at various time points (0, 6, 24, 48, and 72 hours) demonstrated that bacteria persist more efficiently on laminated menus as compared to paper menus. Transfer studies performed to quantitatively determine the ability of bacteria to transfer from menus to fingertips and from fingertips to clean menus showed that bacteria can be transferred for up to 24 hours. The study described here showed that restaurant menus may serve as vehicles for pathogens and hence present a public health issue within the retail food environment.

The authors' aim was to isolate and identify bacteria or yeast that may be present on the surface of 20-peso banknotes from the metropolitan area of Monterrey, Mexico. They randomly studied a total of 70 20-peso banknotes for the presence of bacteria and species of Candida by conventional methods. Out of the 70 banknotes, 48 (69%) were found to be contaminated. The most prevalent species observed was Candida kruseii (19 bills, 27%) followed by Burkholderia cepacia (9 bills, 13%); 22 (31%) bills showed no growth. Of the 48 contaminated bills, four (5.7%) yielded bacteria considered pathogenic and the other 44 bills (63%) yielded bacteria considered potentially pathogenic. Eleven bills showed more than one microbial species. The results of the authors' study show that contamination occurs on paper currency in the metropolitan area of Monterrey. The authors' findings provide evidence that currency banknotes may represent a threat to human health.

The authors assessed the potential of Nigerian currency notes to act as environmental vehicles for the transmission of pathogenic parasites and bacteria. Currency notes obtained from four major cities in Nigeria were evaluated according to standard techniques. Fifty-four (21.6 percent [95 percent CI: 16.50-26.70]) of the first batch of 250 notes, which underwent parasitological analysis, were contaminated with enteric parasites; 133 (53.2 percent [95 percent CI: 47.02-59.39]) of the second batch of 250 notes, which underwent bacteriological analysis, were found to be contaminated with bacteria. Parasites that were isolated from the notes included Ascaris lumbricoides (8.0 percent), Enterobius vermicularis (6.8 percent), Trichuris trichiura (2.8 percent), and Taenia species (4.0 percent). Bacteria that were isolated were Streptococcus species (21.6 percent), Staphylococcus species (12.8 percent), Escherichia coli (13.2 percent), and Bacillus species (5.6 percent). Among dirty/mutilated currency notes, parasite contamination and bacterial contamination were both significantly (p < .05) more pervasive (30.6 percent and 73.8 percent, respectively) than they were among clean and mint currency notes. Lower-denomination notes were more likely to be contaminated than were higher-denomination notes, although the difference was not statistically significant (p > .05). Parasite contamination and bacteria contamination were both most frequent in notes obtained from butchers and beggars. These results suggest that currency notes may be contaminated, especially with bacteria and enteric parasites, and may serve as sources of infection. Personal hygiene to reduce risk of infection is recommended.

This work examined the efficacy of chlorine dioxide (ClO2) gas for the decontamination of Bacillus thuringiensis spores on paper, wood, epoxy, and plastic surfaces. Spores representing an inoculation level of approximately 6 log colony-forming units (CFU) per surface were treated with 5, 10, 15, 20, 25, or 30 milligrams per liter (mg/L) ClO2 gas for 12 hours under 85-92 percent relative humidity and at 22 +/- 1 degrees C. Under the tested treatment conditions, the highest population of surviving spores was found on the paper surface and the lowest was found on the plastic surface (p < .05). The 5 mg/L ClO2 gas treatment inactivated 2.5, 3.6, 4.0, and 4.9 log spores per surface on paper, wood, epoxy, and plastic surfaces, respectively. A greater than 5-log reduction of spores was achieved on each surface after the 15 mg/L ClO2 gas treatment. The minimum ClO2 gas concentration needed to completely inactivate the inoculated spores was 30 mg/L for paper and wood surfaces, 25 mg/L for epoxy surfaces, and 20 mg/L for plastic surfaces. The results of this study may provide insight into the parameters of effective decontamination procedures for Bacillus spores.