Scientists in Britain are worried about a new type of superbug that has entered hospitals.
A paper in medical journal The Lancet Infectious Diseases says the enzyme NDM-1, which resists even the strongest antibiotics, is now widespread in India and Pakistan.
The BBC reports the battle for supremacy between bacterial infection and antibiotics is intensifying and new treatments are in short supply.
Until now, when all else fails, clinicians have been able to fall back on powerful drugs called carbapenems. But bacteria carrying NDM-1 - often E.Coli - are resistant to these and other antibiotics.
The bugs spread easily, usually in hospital but sometimes in the community.
At least 17 of the 37 British patients studied had a history of travelling to India or Pakistan within the past year, and 14 had been admitted to a hospital in these countries - many for cosmetic surgery.
Similar infections have been found in the United States, Canada, Australia and the Netherands.
Researchers say the way to stop NDM-1 is to rapidly identify and isolate any hospital patients who are infected.