We walk around in a cloud of our own microbes
Everyone walks around enveloped in an airborne cloud of bacteria, a bit like the Peanuts character Pig-Pen, and some of the bugs come from our most intimate nooks and crannies. People are standing in another person's microbial cloud the moment they shake hands, says James Meadow of the University of Oregon in Eugene. Bodies are home to an estimated 100 trillion bacteria, viruses and fungi and people leave traces of their microbial communities on surfaces like their phones, and Meadow's team wondered if the air around also carries such signatures. Analyzing the bacterial DNA, they found many species that usually live on the skin and in the mouth, nose and gut, and in the case of women, the vagina.