TWENTY people have died of Creutzfeldt Jakob Disease in Ireland since 1980, according to a recently completed survey to be submitted to the Health Research Unit of the Department of Health.
Dr Catherine Keohane, a member of the CJD advisory group which advises the Minister for Health on the disease, said Ireland had a relatively low incidence of CJD compared with other European, countries. However, it is impossible to get an accurate figure because not all eases of death from the disease were identified.
Dr Keohane said the two ways of investigating whether a person had died from CJD were through a death certificate or an autopsy. She explained: "The diagnosis of CJD is largely a pathology one, based on the change in the brain tissue.
"Getting a figure for the number of eases depends on the number of patients who have autopsies and the number of pathologists examining them. Not all are confirmed as CJD by pathologists and may simply have been clinically diagnosed. There is an inaccuracy with clinical diagnosis.
There is no requirement in this State to carry out an autopsy even if a person is suspected of having died from CJD. Dr Keohane said the incidence of CJD since 1980 was not clustered, nor was there any geographical significance in the figures. As yet, however, no proper surveillance of the disease had been introduced in Ireland.
Dr Keohane was speaking at a special Symposium on Transmissible Spongiform Encephalopathies organised by the Faculty of Pathology at the Royal College of Physicians of Ireland (RCSI). She said that, although a member of the CJD advisory group, she was not speaking on its behalf.
Dr Keohane said that human spongiform encephalopathies were a group of unique neurodegenerative diseases collectively referred to as CJD. A similar group of diseases occurs in animals, including scrapie in sheep and goats and BSE in cattle.
She said there had always been speculation concerning the relationship between the human and the animal diseases, but epidemiological evidence for a link with scrapie was lacking, although a link between one variant of CJD and BSE had been suggested.
Dr Robert Wil, a consultant neurologist with the CJD surveillance unit in Edinburgh, said that 90 per cent of CJD cases were unexplained and occurred randomly. There was no clear linking factor either between those who were struck with the new strain of the disease in Britain.
While feeding offal to Irish cattle has been banned since 1989, Dr Mark Rogers of the Department of Zoology at UCD said, BSE was still occurring in Irish herds because the average incubation period could be five years or over. "I'm not sure we have reached our period of decline yet," he explained.