New antibiotic-resistant superbug NDM-1 spreads from South Asia to U.S.

According to a report in today's issue of "The Lancet Infectious Diseases," a new class of drug resistant superbugs may be traveling worldwide. According to the published study, 37 cases of New Delhi metallo-beta-lactamase (NDM-1) had been reported in the United Kingdom. Several of the cases involved patients who had travelled to India or Pakistan within the past year, several for various medical procedures. The BBC News reports that additional cases surfaced, involving the infection being transmitted from patient to patient within U.K. hospitals. The Centers for Disease Control noted the first three cases in the United States in June 2010, all from patients who also received medical care recently in India.

"Medical tourism" to India has become commonplace for many types of surgeries, including dental, cosmetic, and organ transplants to a lesser degree, as experienced surgeons and first-class hospitals offer health care at a fraction of Western prices. The Lancet researchers published findings from dozens of bacteria samples with the NDM-1 resistance gene in two Indian cities they surveyed, which they said could pose a potential "major global health problem."

NDM-1 is present in gram negative enterobacteria such as E. coli and Klebsiella that is resistant to carbapenem, a class of broad spectrum antibiotic used to treat a wide range of difficult infections. Drug resistant bacteria, like MRSA or those with the NDM-1 mutation are a concern in hospitals, where many patients are on broad-spectrum antibiotics that kill normal bacteria known to contain the antibiotic-resistant bacteria. Hospital in-patients typically have weakened immune systems and secondary infections that allow these resistant strains to grow.

The Centers for Disease Control is urging physicians to pay special attention of NDM-1 in patients with a history of travel to India or Pakistan, particularly when medical treatment was provided in either of those countries.