Rarely does a disease spread through the exchange of money, and no significant illness outbreaks have originated from our ATMs. We could make our money cleaner even though it doesn’t appear frequent for viruses to spread through money.
The best approach to clean money in between transactions is still being researched. Older banknotes can be cleaned of oils and dirt from human fingers by running them through a machine that exposes them to carbon dioxide at a precise temperature and pressure. The heat also destroys bacteria that would otherwise persist on the bills.
Despite having a greater rate of bacterial development than plastic polymers, the fabric used to make U.S. currency is still a combination of cotton and linen. Many nations are switching from paper money made of natural fibers to plastic money, which may be less bacterially friendly. Plastic money has been available in Canada and the UK since 2013, last year switched to bank notes made of plastic.
The travel history of the dollar can be used to track how we transmit disease in other ways even if our money isn’t directly to blame for doing so. Users of the 1998-founded website WheresGeorge.com can track dollar bills by noting their serial numbers. WheresGeorge has documented the geographic locations of banknotes totaling more than a billion dollars in the nearly 20 years since the site’s inception.
In order to track outbreaks, scientists at the Max Planck Institute and University of California, Santa Barbara are now using information from the WheresGeorge website. Even the spread of the 2009 swine flu was forecast using data from WheresGeorge on human movement and interaction rates.
Even though we don’t know how much money contributes to the spread of diseases, it’s probably best to follow mom’s advice when handling cash: wash your hands and avoid putting it in your mouth.