Anopheles gambiae in Brazil: the background to a "silent spread," 1930-1932.

The article analyzes the arrival and identification of the African mosquito Anopheles gambiae in Brazil in 1930, and the initial reactions of scientists and public health authorities against the epidemics of malaria caused by this species. Although this mosquito was recognized as a dangerous vector of malaria, its presence in Brazil was neglected after initial emergency actions in the city of Natal in 1932; this encouraged it to spread silently, resulting in a major malaria epidemic in 1938. This article examines scientific and political issues which caused the fight against mosquitoes to be pushed into the background until 1937 in cooperative efforts between the Rockefeller Foundation's International Health Division and the Brazilian authorities.