Superbug Turns Cure into Killer

Reprint of article by Gloria Chang

British scientists have reported two cases of a "superbug" that thrives on the antibiotics used to kill it.

At St. George's Hospital Medical School in London, two patients, men aged 60 and 64, were treated with the antibiotic Vancomycin after they developed infections from a bacterium called Enteroccoccus faecium. But not only was the bug resistant to its antibiotic, an increasingly common phenomenon around the world, it evolved to become dependent on the Vancomycin, actually needing it to survive!

"What was unusual was that we found the organism had evolved into a Vancomycin-dependent strain," said Ian Eltringham, one of the doctors who reported the cases. "That meant the antibiotic intended to kill it was making it grow. The cure had become the killer."

Enterococcus faecium is normally a harmless bacterium found in the stomaches of most people. But for those with compromised immune systems, the bacterium can cause an infection. Many cases of Vancomycin-resistant enterococcus (VRE) have been reported in hospitals around the world, including Canada, as a result of widespread and overuse of antibiotics.

The first patient developed an infection after undergoing an operation for a ruptured esophagus and other antibiotics got him better. The second patient, admitted one month later, developed his infection after a routine operation and also eventually recovered.

The scientists reported their findings as early as 1996 in the journal Lancet.
They ask, "Have we at last witnessed the emergence of a true superbug?"