For frequent readers of this blog and Carl Zimmer’s The Loom, the bacterium Clostridium difficile may ring a bell. It’s a germ that can cause devastating, intractable gut infections, and is one of the reasons behind the recent development of fecal transplants to try to give the patient healthy gut bacteria to fight back with. C. difficile is on more people’s radar these days, and with good reason. A new Centers for Disease Control report shows that infections from C. difficile and another gut pathogen, norovirus, have grown more common and much more lethal in the last fifteen years. In 2007, they killed more than double the people they’d killed ten years before, jumping from 7,000 to 17,000. Most of those who died were elderly.