Oswaldo Cruz father-in-law, a wealthy Portuguese merchant. Cruz found the seaport of Santos ravaged by an epidemic of bubonic plague that threatened to reach Rio de Janeiro and engaged himself immediately in the combat of this disease. The mayor of Rio de Janeiro authorized the construction of a plant for manufacturing the serum against the disease which had been developed at the Pasteur Institute by Alexandre Yersin and coworkers. He asked the institution for a scientist who could bring to Brazil this know-how. The Pasteur Institute responded that such a person was already available in Brazil: Dr. Oswaldo Cruz. On May 25,
Oswaldo Cruz Cruz. As a child, he moved to Rio de Janeiro with his family. At the age of 15 he started to study at the Faculty of Medicine of Rio de Janeiro and in 1892 he graduated as medical doctor with a thesis on water as vehicle for the propagation of microbes. Inspired by the great work of Louis Pasteur, who had developed the germ theory of disease, four years later he went to Paris to specialize in bacteriology at the Pasteur Institute, which gathered the great names of this branch of science of that time. He was financed by his