‘At a meeting of tile Liverpool Medical Institution on February 4th Professor Warrington Yorke read a paper on the malaria treatment of general paralysis of the insane.

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Professor Yorke... referred to the opportunity that treatment of these cases had given for studying closely the phenomena of malaria. He pointed out that in these induced cases very few doses of quinine sufficed apparently to cure the patients, in contrast with the difficulty of producing this result in ordinary tropical practice. It had also been possible to establish definitely the existence of three species of malaria parasites, the parasites of each species always breeding true. In the induced cases relapse was comparatively rare, and, when it did occur, long delayed. The ineffectiveness of quinine to cure the war cases and patients in tropical practice was due to the fact that they were not primary infections. The factor which governed relapse was the patient's individuality; the occurrence of relapses was in no way related to the strains of parasites with which the patients were infected, to the drugs used, or to the dosage and method of administration.’ (326)