What is a Superbug?

drug resistant microbes
A superbug is a hardy and dangerous infectious disease. (Image credit: CDC/Dr. Ray Butler)

They're not space aliens, they're not insectoid monsters roaming the streets and they're definitely not super heroes. Superbugs are drug-resistant, human-killing microbes that modern medicine struggles to combat. The term has morphed over time, however.

The word "superbug" showed up in the popular press some time after 1970, according to LexisNexis news database searches, and was initially used to describe pollution-eating microbes. Since then, the word has evolved to describe hardy yet dangerous infectious diseases.

"It's entirely a media term, but generally the term refers to bacteria that resist antibiotics," said Dr. Martin Blaser, a professor at New York University's School of Medicine and former president of the Infectious Diseases Society of America. Under that definition, Blaser said even drug-resistant viruses such as HIV (human immunodeficiency virus ) could be considered superbugs because they can also build resistance to man-made drugs.

"If you consider HIV a superbug, it's the worst one there is," Blaser said. The November 2006 World Health Organization's report on AIDS estimates that 2.9 million people worldwide died from AIDS last year. Only about 24,000 to 45,000 of those deaths, however, occurred in North America due to better access to HIV-slowing drugs.

MRSA, or methicillin-resistant Staphylococcus aureus, has earned the superbug title — and is the current media darling under this label — because of its formidable defenses against the drugs used to fight it. As the world population increases and no new antibiotics are discovered, experts think we'll see more microbes like MRSA, but a great deal of research is currently under way to address the growing threat.

MRSA, typically pronounced "mersa," is also frightening because many patients contract it after hospital stays.

Until new weapons are created to fight superbugs, how can you fight them? Most medical experts recommend a simple precaution: Wash your hands with soap and scrub for several seconds, and do so often.

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Dave Mosher, currently the online director at Popular Science, writes about everything in the science and technology realm, including NASA's robotic spaceflight programs and wacky physics mysteries. He has written for several news outlets in addition to Live Science and Space.com, including: Wired.com, National Geographic News, Scientific American, Simons Foundation and Discover Magazine. When not crafting science-y sentences, Dave dabbles in photography, bikes New York City streets, wrestles with his dog and runs science experiments with his nieces and nephews.