On the other hand, areas of the body such as the brain, the circulatory system and the lungs are intended to remain sterile (microbe free). The human body provides many unique environments for different bacterial communities to live.
Where are microbes not found?
In fact, probably the only place on Earth that we can be confident will always be entirely bacteria-free is the lava crater of an actively erupting volcano.
Where are microbes found in the body?
The mouth had the least bacterial variability of any tested region.
What part of the body has the least bacteria?
α-proteobacteria was the predominant phylum of bacteria identified, and was found in all brain samples tested.