Criminals beware: Everything you touch leaves a unique bacterial trail

If you’re germophobic, maybe you should stop reading right now because this one will just keep you up at night.

University of Colorado researchers determined that the average person has about 150 different bacterial species that live on the hands. And if that sounds disturbing, don’t worry–they’re not disease-causing germs.

What’s interesting is that your mix of bacterial species is unique. In fact, the UC researchers estimate that any two people share only about a dozen of the different species.

Which made the researchers go: hmmm.

Could these species leave traces that might be identified like fingerprints?

They swabbed a few computer keyboards and quickly had an answer: Each person who used the keyboards left a unique bacterial trail. And these trails have staying power. The keyboards were left in the open, exposed to direct sunlight and changes in temperature and humidity.

Two weeks later the researchers could still identify which keyboards matched which subjects with more than 70 percent accuracy.

The lead researcher told Reuters Health that when their technique is refined it could become a new tool for forensic scientists.

You can already hear the keyboards clacking away in the CSI writers’ offices.

To Your Good Health,

Jenny Thompson

“People Leave Unique Trail of Germs, Study Finds” Reuters Health, 3/15/10,