The journal Archives of Neurology and the New Scientist magazine have both reported that the genetic type of a 40-year-old woman who has possibly died from CJD (mad cow disease) was unlike that of any of the other patient who had contracted the disease through eating infected beef. This has triggered fears of a new series of deaths.
If it is certified that the woman had a new variant of CJD, not associated with other cases of CJD this could be a sign that the disease may be starting to affect another genetic group with a longer incubation period.
However lead researcher at the University College London, Dr Simon Mead, who examined the dead woman's brain claims that it is too early state that positively, but advised a sustained and close watch on events.
Every year scores of incidents of the fatal CJD are reported and in the last twenty years a new form of the disease has been noticed.
That was when a few people who has consumed infected meat from cattle developed a variation of which was similar to CJD and was equally fatal and most often appeared only years later.
After a slaughtering program removed infected cattle from the food chain, after deaths from CJD peaked in the early 2000s it has rapidly decreased since 2003.
Now scientists believe that a possible "incubation period" may now account for an impending increase in deaths in the near future.
All the fatalities from variant CJD were found to have carried carry a gene modification known as MM.
About 40% could be carrying this variant, and there is a high possibility that only these persons could be susceptible to variant CJD.
The woman, the most recent victim, has been found to have been carrying yet another deviation that about 10 % of Britons carry- VV.
However, Mead whose work was first published in the journal Archives of Neurology, stated, "We can't say for sure whether this is actually variant CJD, or simply a case of "sporadic" CJD in a younger-than-expected patient - it does not have all the features of either.
"It could be a new type of variant CJD affecting VV people, but we would need to see a lot more cases than at present to confirm this.
"What we are doing at the moment is asking people to stay alert and look out for other cases."
Chairman of the government's Spongiform Encephalopathy Advisory Committee (SEAC), which advises on variant CJD, Professor Chris Higgins, does not pay much attention to claims that CJD may reach epidemic numbers.
According to him, “There's certainly no need to panic. This could simply be a case of sporadic CJD, in which case the genetic makeup is irrelevant, as this is found in MM and VV people.
Although research suggests that both groups are vulnerable the incubation periods are so lengthy, sometimes as long as fifty years, that it is more likely that the carriers would die of other causes rather than CJD.
"At the moment there isn't enough evidence to conclude one way or the other” says Higgins.
"We know that it is possible to infect VV mice with variant CJD, but it is actually much harder than infecting MM mice, so even if there were to be a rise, it would not a big rise."
So far, 114 people have died from variant CJD in Britain since 1995 when the disease was first recognized. Besides these there have been 47 other suspected deaths.
