1844-1922

Scottish parasitologist who founded the field of tropical medicine. While practicing medicine in China, Manson studied elephantiasis, a lymphatic disease that causes the tissues of the limbs and genitals to become extremely swollen. In 1877 he showed that the cause of this disease, the parasitic Filaria bancrofti worm, is spread to humans by mosquitoes. Manson's discovery—that an insect can carry a parasite which it transmits to humans—helped Ronald Ross (1857-1932) to identify the parasite that causes malaria, also a mosquito-borne disease.