Where is the Superbug Coming from

Researchers at Cardiff University, the Health Protection Agency (HPA) and International colleagues reported finding a new gene, New Delhi metallo-beta-lactamase 1 (NDM-1), which alters bacteria, making them resistant to virtually all known antibiotics.

Found largely in E. coli bacteria, the most common cause of urinary tract infections, and on DNA structures, the gene can be easily reproduced and passed onto other types of bacteria.

In the article published online this week in the journal Lancet Infectious Diseases, researchers note that the potential of NDM-1 spreading worldwide is “clear and frightening”

One researcher, Dr David Livermore, said, “There have been a number of small clusters within the UK, but far and away the greater number of cases appear to be associated with travel and hospital treatment in the Indian subcontinent.  This type of resistance has become quite widespread there.  The fear would be that it gets into a strain of bacteria that is very good at being transmitted between patients.”

The threat of a serious global public health problem is recognized as there are few suitable new antibiotics in development and none that are effective against NDM-1.

The superbug gene appears to be already circulating widely in India, where the health system is much less likely to identify its presence or have adequate antibiotics to treat patients.

“There is little drug control in India and an irrational use of antibiotics,” Delhi-based Dr Arti Vashisth told the BBC.

Common antibiotics have become ineffective in India because people can buy them over the counter self-medicate therefore using inadequate dosage and too short treatment periods.

Gastroenterologist Vishnu Chandra Agarwal says in the past year he has come across many patients with E.coli infections who have not responded to regular antibiotics.  “In about a dozen cases, I have used a chemical – furadantin – to treat my patients. And it has worked. It makes them horribly nauseous, but it works,” he says.

NDM-1 has also been detected in Australia, Canada, the U.S., the Netherlands and Sweden.  Since many Americans and Europeans travel to India and Pakistan for elective procedures like cosmetic surgery, the threat of this superbug gene spreading worldwide is very real.

Bacteria that produce NDM-1 are resistant to carbapenems, a group of antibiotics reserved for use only in emergencies and the treatment of infections caused by multi-resistant bacteria.

“The potential of NDM-1 to be a worldwide public health problem is great, and coordinated international surveillance is needed,” the authors wrote.

“The spread of these multi-resistant bacteria merits very close monitoring,” wrote Johann Pitout of the division of microbiology at the University of Calgary, Canada, in an accompanying Lancet commentary.

Urging international surveillance of the bacteria, particularly in countries that actively promote medical tourism, Pitout wrote, “The consequences will be serious if family doctors have to treat infections caused by these multi-resistant bacteria on a daily basis.”