superbug

Popular name given to an infectious bacterium that has developed resistance to most or all known antibiotics. The widespread use of antibiotics, their release into the environment, and the carelessness of patients who do not complete a treatment course have all contributed to the dangerous spread of genes conferring antibiotic resistance to their carriers.

Methicillin-resistant Staphylococcus aureus (MRSA) is a superbug that causes problems in many hospitals. Outbreaks of MRSA, which can cause temporary closure of operating rooms and intensive care units, have been met with vancomycin, a ‘last resort’ antibiotic normally reserved for life-threatening infections. But in the spring of 1997, Japanese doctors reported the most convincing evidence yet of the appearance of vancomycin-resistant strains.

In 1998 US researchers successfully synthesized vancomycin. This should also make it possible to synthesize altered versions of the drug with which to treat vancomycin-resistant bacteria. In 2000 the US Food and Drug Administration approved a new type of antibiotic to fight superbugs resistant to other treatments. The drug Zyvox has proved effective for bacteria which are resistant to vancomycin and methicillin. It works by halting bacteria from multiplying earlier than other antibiotics do by stopping the production of proteins needed for the bacteria's growth.