UPDATED 3/6/2013:

Superbugs sound like they should be characters in a comic book, but, in fact, they are real-life bacteria that have become increasingly resistant to antibiotics. Hospitals and nursing homes used to be the only places where they seemed spread, but more recently, outbreaks have been traced to gyms and day care centers.

What was the first superbug?

Methicillin resistant Staphylococcus aureus (MRSA) was first seen by U.S. doctors in the 1960s, when patients at hospitals were diagnosed with staph infections that were resistant to antibiotics. Until the  1990s,, doctors believed that MRSA was only present in hospitals where patients were ill and couldn’t fight off the infection,  Maryn McKenna, author of Superbug: The Fatal Menace of MRSA, pointed out in  an NPR interview.

But then  young patients began showing up at the University of Chicago Medical Center’s emergency room with severe cases of MRSA, which they hadn’t contracted in hospitals. Researchers realized there was a slightly different strain that had adapted to live outside a hospital. At first, it was resistant to fewer drugs than the hospital strain, but quickly became resistant to more antibiotics. Now, the hospital strain and the community strain have merged to create a third strain, which is even more dangerous, according to McKenna.  

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Have there been more recent outbreaks?

Last year, the National Institutes of Health (NIH) Clinical Center dealt with a superbug outbreak, which infected 17 people and left six dead--five others who were infected died, but not directly from the superbug. This superbug was called Carbapenem-resistant Klebsiella pneumonia (CRKP), and can cause pneumonia, bloodstream infections, wound site infections and meningitis.

The superbug was brought into the hospital by a 43-year-old woman who was already infected. Aggressive efforts were made to contain the superbug so that it did not spread throughout the hospital.  The woman was put in an isolated intensive care room, where doctors used masks, gloves and gowns every time they interacted with her.  Throughout her treatments, everything was sterilized or treated as infectious waste. Despite these efforts, however, the superbug spread.

To address the problem, the hospital ripped up plumbing, sterilized rooms and used a new technology called Whole Genome Sequencing that allowed them to decipher the genetic code of the bacteria. They were then able to trace the pattern of how the superbug spread, and found that it had lingered in certain equipment and sink drains.

Maryn McKenna and several other infectious disease experts have pointed out that these infections are happening in hospitals and nursing homes all over the country. Few of them have the same resources as the NIH to track and fight outbreaks.