The bacteria that are resident on any person’s skin and in the air they exhale while breathing has been found to be unique enough to identify any individual. The personal microbial cloud signature was suspected but James F. Meadow, a postdoctoral researcher from the Biology and the Built Environment Center at the University of Oregon, and colleagues are the first to demonstrate that the microbial cloud of any person is unique enough to identify that person.
Eleven volunteers were placed in a sanitized experimental chamber where the microbes that the people released to the air in the chamber were detected. The DNA of the microbes was sequenced with short-read sequencing that identified the class of microbes but was not designed to detect pathogens. Each individual produced a unique microbial cloud of Streptococcus from the mouth and Propionibacterium and Corynebacterium from the skin. The combination of microbes was different enough between any individuals to allow identification of a given individual.
The researchers do not yet know if it is possible to identify a person by their microbial cloud signature if the person is in a group of people. The discovery can be used as an added means of identification for police in criminal investigations and first responders in disasters that involve a large number of people. A person’s microbial cloud signature may become a requirement in the future to help prevent disease and as a fool proof method of identification. At present the speed of identification of a personal microbial cloud signature is about four hours and is impractical but higher speed detection is possible.