There have been at least three Australian patients who have contracted the new bacterial gene which is highly resistant to antibiotics, says experts.

Published recently in The Lancet, scientists have confirmed the NDM-1 gene had been discovered in 37 British patients following the spread from South Asia.

The NDM-1 producing bacteria are resistant to many existing antibiotics such as carbapenems - the type of antibiotics reserved as the last alternative. Two bacteria that have been found to host the NDM-1 gene are E.coli and Klebsiella pneumonia.

The gene was first discovered last year in the case of a Swedish patient who had been admitted to a hospital in India.

Scientists warn that the gene which is responsible for making gut bacteria highly resistant to antibiotics can potentially lead to urinary tract infections, blood poisoning and life-threatening pneumonia.

The study revealed that the gene has been affecting many hospitals and the wider community in India where it is easily transmitted due to contaminated drinking water supply.

From the samples collected in patients from hospitals in Bangladesh, India and Pakistan, they found about 150 patients carrying the superbug.

A total of 37 British patients were also found to have been infected, some who have gone to India or Pakistan for surgery in the previous year.

David Paterson, researcher at the University of Queensland who was also a part of the study said there is at least three cases of the superbug gene in Australia, which include a patient of Indian origin who had travelled to Punjab last year but did not go to the hospital.

The first Australian case of the gene has been published in the Medical Journal of Australia last month, in a man in his late 50s who had gone to India for plastic surgery, told Professor Peter Collignon, fellow infectious diseases specialist of the Australian National University.

Australia has been a part of the medical tourism, said Prof Collignon but it is of a serious concern that the highly resistant gene appeared to be carried in the food and water supply of developing countries.

He warned people that the infections caused by bacteria carrying the NDM-1 gene are multi-resistant and there are no antibiotics available to treat them yet.