Listeria monocytogenes is a bacteria that is the causative agent for the disease listeriosis. Although rare, listeriosis can be very problematic primarily for pregnant women, newborns, adults with weakened immune systems, and the elderly. At a fatality rate of 20%, listeriosis should not be taken lightly. Listeria infections are usually contacted from eating contaminated food and most often cause sepsis and meningitis (inflammation of the brain and spinal cord.)
Jeni's Ice Cream recently found listeria colonies in some of their ice cream. Unfortunately for them it wasn't just one batch, and they have had difficulty narrowing down the exact cause. So, to prevent potentially infecting their customers with a deadly pathogen they decided to close shop until they can effectively eliminate the source.
Although it's starting to get warm out and everyone wants their favorite boutique ice cream, we should be thanking Jeni for avoiding the risk. Also, I hear Jeni's is still paying their employees although they are closed. That's pretty cool of them.