Researchers attacking menacing 'superbug'

Scientists around the world have been working in earnest to improve understanding of an increasingly virulent superbug, Clostridium difficile. The highly contagious hospital-acquired pathogen, designated by the Centers for Disease Control and Prevention as one of the five most urgent threats to the U.S. healthcare system, causes more than 500,000 infections and 29,000 deaths each year at a total societal cost exceeding $5 billion.