Leishman, William Boog (1865–1926)

Scottish army physician who discovered the protozoan parasite that causes the group of diseases now known as leishmaniasis. He was knighted 1909.

Leishman was born and educated in Glasgow, and spent his entire career in the Royal Army Medical Corps. He was posted to India 1890–97. From 1903 he was professor at the Army Medical School. In 1914 he began advising the War Office on tropical diseases, and he became the first director of pathology at the War Office in 1919. He was director-general of the Army Medical Service from 1923.

Leishman discovered the protozoan parasite that causes kala-azar in 1900, using a technique now called Leishman's stain, to examine cells from the spleen of a soldier who had died of kala-azar. He published his findings in 1903 but in the same year Charles Donovan (1863–1951) of the Indian Medical Service independently made the same discovery, as a result of which the causative protozoan came to be called Leishmania donovani.

Leishman also assisted his colleague Almroth Wright (1861–1947) in developing an effective antityphoid inoculation, and helped to elucidate the life cycle of the spirochaete Spirochaeta duttoni, which causes African tick fever.