An encounter with a Jewish prostitute in Vienna in 1908 may have given Hitler neuro-syphilis and provided the 'deadly logic and blueprint for the Holocaust' as well as giving him a reason to attempt to eliminate the mentally retarded, according to evidence presented at the Royal College of Psychiatrists.

That theory supported by 'ample circumstantial evidence though no final proof', according to a team led by Dr Bassem Habeeb, a psychiatrist at Hollins Park Hospital Warrington, in a paper presented to the Royal College of Psychiatrists' annual meeting in Edinburgh.

There has been speculation that Hitler had the infection since his personal doctor, Theo Morrell expressed his own suspicion in his private diary. But the theory has never been rigorously examined, say the researchers.

'But if Hitler's life is looked at through the lens of a syphilis diagnosis, one clue leads to another until a pattern of infection and progressive infection emerges, a disease that may have defined him from youth as an outsider and that progressively ravaged his body and mind.

Hitler put syphilis high on his political agenda, devoting 13 pages to the disease in Mein Kampf. The job of 'combating syphilis... the Jewish disease... should be the task of the entire German nation,' he wrote. 'The health of the nation will be regained only by eliminating the Jews'.

According to Dr Theophanous, Hitler's bizarre belief that syphilis was a hereditary disease that was originated and propagated by the Jews and resulted in insanity and mental retardation' could be the reason he attempted to eliminate the mentally retarded.

His doctor, Theo Morrell noted his Parkinson's disease, severe gastric crises, skin lesions and violent mood swings as evidence that he had contracted syphilis - as well as 'sudden criminal behaviour, paranoia, grandiosity and mania, all of which changes show in cases of neuro-syphilis.