The NDM 1 gene, which creates what some experts describe as "super superbugs," has spread to germs that cause cholera and dysentery, and is circulating freely in other bacteria in the Indian city capital of 14 million people, the researchers said.
"The inhabitants of New Delhi are continually being exposed to multidrug-resistant and NDM 1-positive bacteria," said Mark Toleman of Britain's Cardiff University School of Medicine, who published the findings in a study on Thursday.
A "substantial number" of them are consuming such bacteria on a daily basis, he told a briefing in London. "We believe we have discovered a very significant underlying source of NDM 1 in the capital city of India," he said.
It first emerged in India three years ago and has now spread across the world. It has been found in a wide variety of bugs, including familiar pathogens like Escherichia coli, or E. coli.
"We would expect that perhaps as many as half a million people are carrying NDM 1-producing bacteria as normal (gut) flora in New Dehli alone," Toleman said.
"The potential for wider international spread of ... NDM 1 is real and should not be ignored," he wrote.
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