A new type of superbug, which no known antibiotics can treat, has been discovered.

Scientists say it raises concerns about potentially untreatable infections.

Pigs and meat sold in China are carrying a bacteria which has a gene making it resistant to even the drugs used as a last resort by doctors.

The mutation has also been found in hospital patients in China, and BBC reports that there is evidence that it has spread to other countries in the region such as Laos and Malaysia.

The authors of the research, published in the Lancet journal, say that the emergence of the MCR-1 gene "heralds the breach of the last group of antibiotics, polymyxins, by plasmid-mediated resistance".

They also warn that although currently confined to China, the gene "is likely to emulate other global resistance mechanisms".

The findings come during the World Health Organisation's World Antibiotic Awareness Week, which is aimed at avoiding the further emergence and spread of antibiotic resistance.

A survey found that 64% of people questioned across 12 countries believe antibiotics can be used to treat colds and flu, despite the fact that antibiotics have no impact on viruses.

WHO Director-General Dr Margaret Chan said, "the rise of antibiotic resistance is a global health crisis, and governments now recognize it as one of the greatest challenges for public health today".

Speaking to Newstalk Lunchtime today, Dr Rob Cunney HSE lead for the antibiotic resistance programme, said that he does not think medicine threatens "to go back to the dark ages" because of the discovery.

However he added that "certainly the threat of antibiotic resistance is real - it does threaten the effectiveness of what is probably one of the most important medical advances of the last 100 years".