Infection monitoring agency Health Protection Scotland revealed the mutated form of E.coli was detected in a patient who was not already in hospital and had not been travelling in India – raising the possibility the superbug is starting to spread in the Scottish community.
Known as NDM-1 producing E.coli, the bug is one of a new strain of bacteria of particular concern because they threaten what is almost the last line of defence doctors have against infections.
Dr Camilla Wiuff, healthcare scientist for Health Protection Scotland, said: "Up to now the industry has been able to innovate stronger and stronger drugs, but at this stage the bacteria have developed so many multi-resistant organisms there are no good new alternatives on the market."
Experts have painted a picture of a worst-case scenario where the world returns to an era before the discovery of penicillin in the 1920s and simple infections do not respond to treatment and routine operations become life-threatening.
The new breed of bug seems to have first been imported to the UK by patients who had been treated abroad, including people who had undergone cosmetic surgery or organ transplants in the Indian subcontinent, where NDM-1 is now known to circulate in hospitals. It can lead to urinary tract infections and blood poisoning.
The first four cases of NDM-1 producing E.coli reported in Scotland were found in patients not connected to each other, but had travel links.
However, the latest patient, who was suffering from a urinary tract infection, was otherwise well and had not visited the associated countries. This person has now recovered.
Dr Wiuff said the primary concern was the potential for the superbug to infect hospital patients with weakened immune systems.
She said they would face the prospect of becoming increasingly unwell as treatments failed to combat the superbug and they ultimately faced the possibility of death.
However she stressed at the moment the problem was extremely rare in the UK.
She said: "These are very, very early days. This is one case we have seen in the community in Scotland so far. For the general person in the community and in hospital it is a very small risk."
As it is complicated to rule out any link between the patient and other people close to them who have travelled recently, the case may still not be evidence of spread within the UK.
Eminent microbiologist Professor Hugh Pennington said E.coli NDM-1 was a particular concern because E.coli genes move around, recombining with other E.coli.
He said: "It is evolution in real time. You can almost watch it happen. For some people who get sick with this bug you do require antibiotic treatment because it can spread into the bloodstream. Then you are really desperate.
"If you do not have one or two antibiotics that work you are at death's door. We really do need to keep a very close eye on it."
He said the fact the case had been identified was good news in that it was important to be aware if it was on the move.
Healthcare Protection Scotland has urged frontline clinicians and NHS laboratories to remain vigilant in monitoring for the superbug.