Each of us give off millions of bacteria from our human microbiome into the air around us every day, and that cloud of bacteria can be traced back to us in lab tests.
The findings could help explain the mechanisms involved in the spread of infectious diseases in buildings. It might also help forensic scientists identify or determine where a person has been.
It is known how humans “contaminate” surfaces through touch and spread pathogens through the air, but little was understood about the personal microbial cloud – the airborne microbes we emit into the air.
Now researchers at the University of Oregon have demonstrated the extent to which humans possess a unique “microbial cloud signature.”
Dr James Meadow said: “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.
“Our results confirm that an occupied space is microbially distinct from an unoccupied one, and and demonstrate for the first time that individuals release their own personalized microbial cloud.”
Scientists sequenced microbes from the air surrounding 11 different people in a sanitised experimental chamber.
Most of the occupants sitting alone in the chamber could be identified within four hours just by the unique combinations of bacteria in the surrounding air, the findings published in the journal PeerJ revealed.
The striking results were driven by several groups of bacteria that are ubiquitous on and in humans, such as Streptococcus, which is commonly found in the mouth, and Propionibacterium and Corynebacterium, both common skin residents.
While these common human-associated microbes were detected in the air around all people in the study, the report found that the different combinations of those bacteria were the key to distinguishing individual people.
The findings emerged from two different studies and more than 14 million sequences representing thousands of different types of bacteria found in the 312 samples from air and dust from the experimental chamber.
Source: The Telegraph