The true return on the dollar: No clean bill of health

Maybe it's time for some literal money laundering. A study presented today at the General Meeting of the American Society for Microbiology reports that paper currency is commonly contaminated with bacteria, and this may play a role in the transmission of potentially harmful organisms.

One-dollar bills collected at a food concession stand at a high-school sporting event and a check-out lane at a grocery store near Dayton, Ohio were tested for bacterial contamination by Dr. Peter Ender and his associates at Wright-Patterson Air Force Base, Ohio.

They found that the majority of the 68 dollar bills they studied were contaminated with the types of bacteria that can cause infection. Five bills were contaminated with types of bacteria that commonly cause infections in healthy people, and 59 were contaminated with types of bacteria that can cause significant infections in hospitalized patients and those with depressed immune systems. No bacterial contamination was detected on four bills.

"One-dollar bills are widely used and each is exchanged many times," Ender says. "If some are contaminated with bacteria, there is potential to spread these organisms from person to person." There are very few data on the degree to which paper money is contaminated with bacteria.

"It is important to note that this study of 68 dollar-bills out of the billions in the general circulation did not prove that bacteria can be spread from person to person during the exchange of money," Ender cautions. "A more complex study involving molecular biologic methods would be required to accomplish that objective. However, this study highlights the possibility that money can be a vehicle for rapid spread of bacteria."

Patrons at each of the study locations were asked to exchange a one-dollar bill for a new bill, and contamination on the used bills was analyzed using standard microbiologic techniques. Five bills were contaminated with Staphylococcus aureus and Klebsiella pneumoniae, which can cause infections in healthy people. Fifty-nine were contaminated with Staphylococcus, Streptococcus, Enterobacter, Pseudomonas, and other types that can pose infection risks in hospitalized or immune-compromised patients.

The American Society for Microbiology, headquartered in Washington, DC, is composed of over 43,000 scientists and health professionals. Its mission is to promote research and research training in the microbiological sciences and to assist communication between scientists, policy makers, and the public to improve health, the environment, and economic well-being.

This release is a summary of a presentation from the 101st General Meeting of the American Society for Microbiology, May 20-24, 2001, in Orlando, Florida. Additional information on these and other presentations at the 100th ASM General Meeting can be found online at http://www.asmusa.org/pcsrc/gm2001/presskit.htm or by contacting Jim Sliwa (jsliwa@asmusa.org) in the ASM Office of Communications. The phone number for the General Meeting Press Room is 407-685-8061 and will be active from 10:00 a.m., May 20 until 12:00 noon, May 24.