People are being misled by reports that the worst of human BSE infection may be over, the father of a teenage victim has said.
CJD has killed 122 people since 1995
In a study in the medical journal, the Lancet, the National CJD Surveillance Unit said the number of people dying from the human form of mad cow disease each year is falling.
But Don Simms from Belfast, who won a landmark legal case to secure a new form of treatment for his son, Jonathan, 18, insisted the full facts have still to
He said the details had been made public to "curb public hysteria".
According to the National CJD Surveillance Unit the disease has taken 122 lives in the UK since it emerged in 1995.
Last year 17 people died, compared to 20 in 2001 and 28 in 2000 - when the disease reached its high point.
There has been one provisionally recorded death so far this year. Eight people thought to have the incurable disease are still alive.
Jonathan Simms was injected with the blood-thinning drug Pentosan Polysulphate (PPS) after his family won the right to have him treated in the courts.
The family hope the treatment, which has been tested on
animals infected with scrapie, may prolong his life.
bears striking similarity with vCJD in terms of clinical symptoms
After two spells in a hospital where a top neurosurgeon
infused the drug directly into his brain, Jonathan has been cared for by his
parents and medical staff at his home in west Belfast.
Mr Simms was reluctant to say too much about the impact of PPS.
"It has not caused the side effects that was predicted by some scientists,"
But he warned it was wrong to offer too much hope that infection rates were
"People could be carrying the disease for years before they realise," he said.
"It's believed some elderly people have been diagnosed with
Alzheimer's when it could be vCJD because no simple diagnostic test is available yet.
"With an incubation period of about 40 years how do we know? Alzheimer's
bears striking similarity with vCJD in terms of clinical symptoms."