NIH scientists researching how the antibiotic resistant Klebsiella pneumoniae bacterium spread to 18 patients in the Clinic Center of the National Institutes of Health in Bethesda, MD, used gene sequencing to trace the exact path of the spread. It began with one patient who was transferred from a New York hospital in June 2011, who had been isolated and under rigorous infection control precautions at the Clinic. Six patients died of the infection. Gene sequencing allowed researchers to chart mutations in the bacterium as it traveled within the hospital and to identify whether it leapt from infected patients throats or lungs, a potential clue of how it spread. The bacterium lived longer than anyone thought, and spread in unexpected ways. The study was reported in the journal Science Translational Medicine. Read the New York Times story by Gina Kolataand the Wall Street Journal story by Christopher Weaver and Jonathan D. Rockoff.