Medical tourists bring home new superbug
August 12, 2010
Medical tourists seeking treatment in Asia are bringing home a dangerous type of bacterial infection that's resistant to nearly all known antibiotics, according to a new report in the journal the Lancet.

Doctors identified 29 patients in the United Kingdom with the new infections. Most had traveled to India, Pakistan or Bangladesh for medical procedures, including elective cosmetic surgery. Dozens of patients from Asia also got the infections, according to the researchers, from Cardiff University.

Most of the new infections involved one of two common bacteria: E. coli or Klebsiella pneumoniae. In each case, the bacteria had acquired a gene making them resistant to all but one or two known drugs. The gene, with the faceless name of NDM-1, protects the bacteria by producing an enzyme that destroys antibiotics. It was first identified last year, although when the Cardiff researchers took a look for older examples, they found a handful of cases dating back as far as 2003.

While the bacteria are resistant even to antibiotics that are generally considered a "last resort" against resistance, they are susceptible to an older antibiotic, colistin, according to Dr. David Livermore, director of antibiotic resistance monitoring at the UK's Health Protection Agency. Colistin has not been widely used since the 1970s because of toxic side effects, according to Dr. Alex Kallen of the U.S. Centers for Disease Control and Prevention (CDC).

The new strains appear to be widespread in south Asian medical centers and have also been spotted in Canada, Australia, the Netherlands, Sweden and the United States. In June, the CDC flagged three cases where patients were infected with bacteria carrying the NDM-1 gene. All had undergone medical care in India.

The CDC told doctors to be alert to the possibility of resistant infections in any patients who have received medical care in Pakistan or India. The CDC also said patients found to be infected with the new strain should be isolated from other patients, with doctors and nurses taking extra precautions - such as wearing gloves - to prevent its spread.

The new strains are mostly or completely confined to hospitals and are a concern only for people getting medical care in those countries, Livermore told CNN.

While the number of known cases is small, the fact that the new gene is found in different kinds of bacteria is a significant worry. This versatility gives NDM-1 at least the potential to spread more quickly and more widely than if it were confined to a single bacteria strain. "That's a very concerning thing," says Kallen.

Adds Livermore, "What you're looking at here is like coastal erosion, a gradual winding down of our ability to treat infections. The worry is, as time goes by, infections become a little harder and harder to treat. So much of modern medicine depends critically on our ability to treat infections as they arise."

The Lancet authors say the growing popularity of travel for medical care makes it unlikely that this particular genie will ever be stuffed back in the bottle. But they warn that such travel should probably be discouraged, saying the establishment of NDM-1 carrying strains around the world is a "clear and frightening" possibility.

Posted by Staff at 12:00 AM