The researchers gathered 11 test subjects, put them in a germ-free compartment and then collected 312 samples of the air surrounding them.
They also gathered air samples from unoccupied compartments as well.
After sequencing the DNA of the bacteria contained within the air samples, the researchers found that they could identify most of the 11 test subjects in only four hours just by a distinctive combination of microbes in the air.
The scientists were able to detect the presence of commonly carried strains of bacteria such as Streptococcus, Propionibacterium and Corynebacterium around all of the test subjects. But they found that each of their subjects gave off different combinations of the bacteria that made the individual’s “microbial cloud” unique.
“We expected that we would be able to detect the human microbiome in the air around a person, but we were surprised to find that we could identify most of the occupants just by sampling their microbial cloud,” said lead author James F. Meadow, in a press release.
The researchers said that their study revealed a distinct difference in the samples taken from the compartments occupied by the test subjects and those from an unoccupied unit.
The findings were published in the September 22, 2015 edition of the journal PeerJ.
The researchers believe that their findings could provide insight and an understanding of the mechanics behind the spread of contagious disease within buildings or other closed spaces.
They also say that the methods used to make their findings could be used some day in forensic studies. For example, investigators might be able to learn the identity those who were at specific location or determine if a suspect had been at the scene of a crime he or she is accused of.