Malaria and Public Health Measures in Colonial Urban Zanzibar, 1900-1956

arly twentieth century environmental and sanitary engineering campaigns implicated three major areas in Zanzibar. As records from the Department of Medicine and Public Health and other administrative files from the Provincial Administration Department and Public Works Department show, they included the reclamation of the Creek and swampy ground. The filling of natural depressions caused by quarrying works started from 1930. These measures were a response to the growing medical understanding that malaria was spread by mosquitoes. From the early twentieth century, Zanzibar decided to embark on anti-malarial campaigns which focussed on controlling both Anopheles gambiae and A. funestus. These two malaria species bred in swamps, banks of rivers, potholes, shallow depressions, in hoof-prints of cattle, earthen jars, sailing boats, canoes, lighters, borrow-pit and flooded rice-fields. In 1913, the Colonial Office sent Professor W. J. Ritchie Simpson, a British physician and a pioneer in tropical medicine, to visit British colonies in East Africa. Simpson, who formerly worked as a health officer for Calcutta, India in the 1890s and was a founder of the Journal of Tropical Medicine in 1898, was from 1913 an advisor of the Secretary of State for the Colonies on health matters. He visited Zanzibar, Kenya and Uganda to investigate health conditions, and to propose measures to be taken to improve health of the “native” population, (Indians, Arabs and Africans). Simpson’s survey confirmed that mosquitoes bred during rainy seasons. He recommended to the Zanzibar authorities that they refill the Creek in order to stop epidemics. The anti-malarial works that focused on reclamation of land and swamps had just started in the United States of America. Since the early 1900s, the United States had been involved in the campaigns against yellow fever in the Panama Canal area.