Biologist Daniel Smith crouched in an empty patient room at the new University of Chicago hospital and dragged a white cotton swab across the gleaming tile.
Smith studied the dust-smudged tip before breaking it off into a plastic tube labeled "floor."
"A good sample for us," said Smith, securing the tiny vial in a box chilled by dry ice. "Although you can't see them, there are literally billions of (bacteria) cells on these surfaces."
Like scientists who began classifying the world's plants and animals centuries ago, Smith and his colleagues at Argonne National Laboratory are embarking on a similar exploration, only in the micro realm.
Over the next year, they plan to trace the ebb and flow of the hospital's microbiome — a vast wilderness of viruses, fungi and, perhaps most importantly, bacteria — to better understand how it may affect human health in an environment where about 100,000 people die nationally every year from acquired infections.
The effort, known as the Hospital Microbiome Project, follows similar surveys of bacterial communities in the human body, where the single-cell organisms outnumber human cells by 10 to 1. It is also part of a growing area of microbial research, bolstered by recent advances in molecular biology and computer science, that has led some scientists to wonder whether the strongest forces shaping human life may not, in fact, be human.