Warrington Yorke was the son of the Rev. Henry Lefroy Yorke, a Wesleyan minister, and Margaret (Warrington) Yorke. He was educated at University School, Southport, Epworth College, Rhyl, and the University of Liverpool, where he was awarded the senior Lyon Jones scholarship and the Derby exhibition in clinical medicine. Shortly after a post as house physician to Sir James Barr at the Royal Infirmary he was elected to the Holt fellowship in physiology, and studied under the direction of Dr Charles Sherrington.
Two years after obtaining his M.D. he went to Nyasaland with Wakelin Barratt. They investigated twenty cases of blackwater fever, finding that haemoglobinurea invariably followed quinine administration for actual or suspected malaria, but that the concentration of quinine in the blood was never of sufficient concentration to produce intravascular haemolysis, the cause of which remained unknown.
In 1909 he was appointed research assistant to Anton Breinl at the Runcorn Laboratory, where in a few months he became director, carrying on studies of the pathogenic trypanosomes of large animals. In 1910 he was able to confirm the findings by Stephens and Fantham of posterior nuclear forms in trypanosomiasis in patients from North-East Rhodesia. With Stannus he suggested what was afterwards proved to be correct that the vector was G. morsitans in this disease they had called trypanosomiasis rhodesiense. Working with Kinghorn he showed it was responsible for infecting game and transmitting the disease from game to man.
From 1913 to 1929 Yorke held the Walter Myers chair of parasitology. After service in the R.A.M.C, in the First World War he undertook investigations on malaria with, among others, Stephens, Blacklock and MacFie, and continued his work on blackwater fever, refuting the claims of Plehn that it was primarily a disease of the kidneys. In 1929 he was appointed Alfred Jones professor of tropical medicine. For the last fifteen years of his life he did much towards the development of chemotherapy, producing a series of trypanocidal compounds, the later members of which were found to be active against several other parasites.
Between 1909 and 1942 Yorke and his colleagues produced 165 reports and papers, the majority of which appeared in the Annals of Tropical Medicine and Parasitology and added greatly to the fuller understanding of many tropical diseases. His monograph, The Nematode parasites of vertebrates, written in collaboration with P. A. Maplestone, was published in 1926.
He was very active on societies and committees. He was twice vice-president of the Royal Society of Tropical Medicine and Hygiene, and was awarded its Chalmers memorial gold medal in 1925. He was a member of the Société Belge de Médecine Tropicale and of the Société de Pathologie Exotique de Paris, and corresponding member of the Helminthological Society of Washington. He also served on committees of the Medical Research Council, of the Royal Society, of the League of Nations and of Imperial Chemical Industries, and was a vice-president of the Anglo-Soviet Medical Union.
Yorke was a good teacher, and essentially a kindly man although his highly critical mind made him at times very outspoken. He married Miss Elizabeth Anne Greening. They had one daughter, and a son who was a prisoner of war in Japanese hands when his father died in 1943.
Richard R Trail
[Brit.med.J., 1943, 1, 585 (p); Lancet, 1943, 1, 601, 635 (p); Nature (Lond.), 1943, 151, 581-2; Obit. Not. roy. Soc., 1942-4, 4, 523-45 (p), bibl.; D.N.B. 1941-1950, 982-3.]