The victims, all men from the Ashford area of Kent, are being treated at Guy's Hospital in London. Alan Colchester, a neurologist at the hospital, who is treating the patients, warned that they "may be the first of many" still to come.
Two of the patients are aged under 40, which will reawaken fears among scientists and advisers to the Government that it is the same strain of CJD which last month was tentatively linked to exposure to mad cow disease, or BSE, in the 1980s.
In the past two years, 10 people in Britain have developed a previously unknown form of CJD, the human form of BSE. When it was identified earlier this year, the only explanation that scientists were able to offer was that the agent which causes BSE might have jumped the "species barrier" between cows and humans to cause the infection.
Scientists at the CJD Surveillance Unit in Edinburgh, who first identified the new strain, had also suspected that it might originate in BSE because no other cases had been found in other countries. However, French doctors report today in the medical journal the Lancet that a 26-year-old mechanic from Lyon had died, apparently of the new strain of CJD. France has only recorded 16 cases of BSE.
"That might suggest that this new strain is not linked to CJD," commented Professor Peter Smith, an epidemiologist who is a member of the independent scientists advising the Government on measures to protect public health from BSE.
But statistically, the two patients under 40 could be the earliest indications of an epidemic of CJD. Sheila Gore, an expert in biostatistics at the Medical Research Council, has told the Independent that just four cases of the new strain of CJD this year could presage the rapid growth in the occurrence of the disease that would class as an outbreak.
Two of the three patients in Guy's Hospital were named yesterday: Graham Brown, a 36-year-old divorced member of Kent Fire Brigade, and Barry Baker, 29, of Durrants Green. The third victim, whose identity is not known, is said to be 56, which makes it unlikely that they have the new strain of CJD.
Mr Brown, who lives in Ashford, has been cared for at home by his sister, who is a nurse. He had reportedly been ill for about 18 months. The first case of BSE was reported in 1985 on a farm in Ashford.
Dr Anne Farebrother, consultant in public health medicine with the East Kent Health Authority, said one of the three had recently undergone a brain biopsy, the results of which had proved negative. But she said that was not conclusive evidence that he did not have the disease, because a biopsy examines only a small part of the brain.
"The problem with CJD is that there is no real specific test to show if people have it or not," said Dr Farebrother.
The CJD Surveillance Unit could not confirm last night whether it was previously aware of the three people recently admitted to hospital. Its last tabulated figures covered CJD cases in the UK up to the end of March.Reuse content