Pretext or prophylaxis? Racial segregation and malarial mosquitos in a British tropical colony: Sierra Leone.

Abstract

Abstract In 1901 the British decided upon a policy of racial residential segregation in their tropical colonies. This policy was ostensibly based upon the discovery three years earlier, by Ronald Ross of the Indian Medical Service, that the anopheles mosquito was the vector for malaria. “Native peoples” were already infected with malaria, colonial officials from Britain were not. Thus, if one could separate residential zones of the two by a distance too great for a mosquito to traverse, then one could protect the health of one's colonial officers. As mosquitos were believed to bite only at night, the officer could safely work among “colonial subjects” by day; only nocturnal segregation was necessary. Reputedly the most malarious place in the British Empire, Sierra Leone was chosen as the test locale for two malaria control expeditions in 1899 and in 1900. The expeditions' conclusions pointed to a range of preventive measures. The fact that residential segregation was the primary method of prophylaxis chos...