Scientists and neurologists from around the world have travelled to Belfast to study the case of a teenager suffering from CJD, who is receiving a radical new drug treatment.

The 19-year-old from west Belfast is having drugs injected directly into his brain in the world's first attempt to halt the spread of the ravaging disease.

His father Don organised today's event to demonstrate how Jonathan had responded to the unprecedented treatment.

He told PA News: "This young man has lived a year longer than predicted and 10 months over the average life expectancy of variant CJD victims.

"We have witnessed small but significant changes in his condition since going on to this treatment," he said.

Jonathan Simms, an A-Level student and promising international schoolboy footballer, was struck down by the human form of BSE two years ago.

But it was only after his family won legal battles at the High Courts in London and Belfast last December that health chiefs agreed to let infusions of the blood-thinning compound Pentosan Polysulphate (PPS) be administered.

Eight months into the treatment Mr Simms cautioned against labelling the drug a new Penicillin, but he admitted the family was hoping for the best.

Among the experts attending the conference at a hotel in the city is Professor Katsumi Doh-ura, a Japanese scientist who has conducted the most recent animal studies on PPS.

Dr Stephen Dealler, a microbiologist at Lancaster Hospital and Dr Nikolai Rainov, a consultant neurosurgeon at the Walton Centre in Liverpool, who have been closely involved with the family from the start were also due to take part.

Dr Craig Heath from the Edinburgh CJD Surveillance Unit and Dr Mark McClean, the Simms' trusted GP in Belfast have also pledged to attend.

Mr Simms added: "It is all about reporting on Jonathan's progress on PPS.

"What we hope to do is enable those who had doubts about this medicine and its safety to have a chance to address all the questions through these experts.

"We also want to aid other families who wish to go down the same route without having to jump the hurdles we had to," Mr Simms said.