EXPERTS fear the strain of Clostridium difficile that has killed eight people at the Vale of Leven Hospital, and been involved in the deaths of eight more, is as deadly as smallpox.
The strength of the 027 strain is under investigation, but the rate of fatalities in the Greater Glasgow and Clyde hospital, in West Dunbartonshire, has horrified bacteriologists.
The strain is 20 times more toxic than normal C diff, but ordinaril
y it would still only be expected to claim the lives of 7% of the people it infects.
At the Vale of Leven, 22 people with the infection have died in the past six months. In eight cases, C difficile was believed to be the main cause of death.
There have been calls for the Scottish Government to launch an inquiry into why it took so long for the hospital to raise the alarm when worryingly high numbers of cases can be traced back as far as January.
Health Protection Scotland is constantly reviewing its guidance on the administering of antibiotics. Too many can leave patients vulnerable to C difficile by killing off the friendly bacteria in their bodies, while too few can fail to treat the illness they are in hospital with.
However, it is the damage the 027 strain caused once it had taken hold in the Vale of Leven that is of greatest concern.
Hugh Pennington, professor of bacteriology at Aberdeen University, said: "This horrendous death rate – that's an appropriate word to use – requires explanation.
"Were a lot of cases undetected? I think there's more to it than that. If it's a new strain killing that many, well, that's a mortality rate of smallpox from the middle ages.
"If you are looking at the history of infectious diseases, there are very few that approach that level of mortality."
Between 2004 and 2006, 90 people died from C diff in three Kent hospitals, in Britain's deadliest superbug outbreak. However, that was out of 1,176 who had been infected – a lower rate than in Vale of Leven.
Pennington said: "With this level of infection, eight deaths is a hell of a lot. It's outrageously high.
"It is possibly more virulent and produces more toxins than previous strains."
The Vale of Leven outbreak has already raised C difficile's profile above that of MRSA, the previously better known hospital superbug.
There are fears alcohol wipes used to prevent the spread of MRSA may aid C diff, as they stimulate the growth of pores, allowing it to move more easily from one patient to another.
This means the Scottish Government and health boards may have to rethink their approach to tackling superbugs.
Pennington said: "It's something we've been concerned about for some time. Now this 027 strain has raised the profile of C diff, and it has emerged as a serious problem.
"It's had a very low priority until very recently and seems to have gone under the radar."
Health Protection Scotland, which is facing questions from Scottish Labour on its role in the failure to raise the alarm earlier, is at a loss to explain why the Vale of Leven outbreak proved so deadly.
Dr Anne Eastaway, consultant microbiologist at Health Protection Scotland, said: "There are suggestions from Canada that 027 is a strain that spreads easily, but that's not a constantly held view.
"The issue over deaths is less clear-cut.
"We don't really know the answer (as to why the Vale of Leven outbreak proved so deadly] yet."
She said guidance on the strength of prescriptions of antibiotics was a "constant balancing act" between leaving patients vulnerable to C diff and running the risk of them contracting other infections.