A new study in the Lancet medical journal (UK) suggests that variant Creutzfeldt-Jakob disease (vCJD), the human variant of Mad Cow Disease, may not peak in the human population for several decades, by which time many thousands of beef eaters and hospital patients that have received tainted blood transfusions could die. The study shows how Kuru, a similar fatal brain-wasting prion disease in New Guinea, has been found to have an incubation period of 35 to 41 years.
Researchers suspect it could be longer for vCJD because the infection is transmitted between species, from cows to humans. The 160 fatal human cases of the disease that have already surfaced around the world could represent a distinct genetic subgroup of the population with an unusually short incubation period, according to John Collinge, the study leader and a professor at University College, London. There could be "substantial underestimations" in recent estimates of the size of the vCJD epidemic, Collinge said in a report in The Lancet medical journal.