Yellow fever in Rio de Janeiro and the Pasteur Institute Mission (1901-1905): the transfer of science to the periphery.

Science, a purely European enterprise, began to be exported to peripheral countries in the nineteenth century. The rapid expansion of bacteriology is a striking example of this. But at the same time, the transformation of bacteriology into a well-established and codified scientific discipline hampered the diffusion of bacteriological knowledge, because the laboratory practice that developed in peripheral countries in the first wave of enthusiasm for the "miracle-making" science often failed to conform to the discipline's new, more stringent professional standards. The problem was ofparticular importance in bacteriology, in whose birth the techniques which allowed appropriate visualization, isolation, and characterization ofmicro-organisms played a crucial role. Indeed, debates on technical aspects of bacteriological investigation were at the heart of early controversies in this field. The story of the search for the agent of yellow fever in Rio de Janeiro illustrates this evolution ofbacteriology. In the 1880s and 90s numerous enthusiastic Latin American adepts of the new science started to look for the aetiological agents of tropical diseases. In Brazil, a favourite target of bacteriological studies was yellow fever. However, the efforts of many bacteriologists notwithstanding, both the epidemiology of the disease and the nature of its aetiological agent remained for long mysterious. There were a dozen or so triumphant announcements of the isolation of the "yellow fever germ" in the 1880s and 90s. Many of them came from physicians working in Rio de Janeiro, a city which suffered from regular outbreaks. But although some of those early announcements were at first received with interest by bacteriologists in Europe, they were ultimately rejected because they no longer conformed to the new, rapidly changing standards of bacteriological investigation. Investigators who had no direct contact with the few centres in which these international standards were elaborated had, even in Europe, difficulty in achieving the proper (i.e., recognized) technical level. The achievement of such standards in a peripheral country was even more difficult. The mystery of yellow fever was finally solved by the American military delegation to Cuba, led by Major Walter Reed. The Reed Mission (1900-1) got the credit for the discovery, based on the epidemiological observations of a Cuban physician, Carlos