Following the death of his father Bento Gonçalves Cruz in 1892, Oswaldo Cruz became responsible for supporting his mother and four sisters. Back then, microbiology research was but a fledgling field in Brazil and so it was almost impossible for a doctor fresh out of medical school to forego clinical practice. Moreover, Cruz had a wedding date set and would soon have a growing family. The solution was to take over his father’s medical office in the house on Rua Jardim Botânico, as well as his job at the medical clinic at the Fábrica de Tecidos Corcovado textile.
Cruz got married in early 1893. As a wedding gift, his father-in-law, Manuel da Fonseca, presented him with a modern laboratory for clinical analyses, set up on the first floor of Cruz’s new home in Jardim Botânico. Another opportunity appeared the very next year: Egydio Salles Guerra, Oswaldo’s future physician and biographer, invited him to work at the General Polyclinic in Rio de Janeiro, a philanthropic institution established in 1882 at the initiative of physician Carlos Arthur Moncorvo de Figueiredo. Cruz’s task: to set up and head a pathological analysis and microbiology laboratory, attached to the Syphilitic and Skin Diseases Service, headed by Antonio José Pereira da Silva Araújo.
Cruz threw himself enthusiastically into his work. The General Polyclinic was one of the few institutions in Brazil that applied the theories of Louis Pasteur to the diagnosis and treatment of infectious disease. It was a place where he could exchange experiences and apply his knowledge of microbiology.
It was also a fine place to cultivate friendships. Together with Salles Guerra, Antônio José Pereira da Silva Araújo, Aureliano Werneck Machado, and Alfredo Porto, Cruz formed the “group of five ‘Germanists’,” a label these scientists earned for their dedication to the study of German—which was, alongside French, one of the languages in which the era’s cutting-edge medical and scientific papers were published.
When he finished his studies in Paris and returned to Brazil in August 1899, Cruz resumed his clinical practice. At the same time, on Travessa de São Francisco (now Rua Ramalho Ortigão) in downtown Rio, he opened a private urology practice and set up a modern laboratory for research and clinical analyses—the first of its kind in the city. This was also when he helped found the Botafogo Polyclinic, a philanthropic institution that was the brainchild of physician Luiz Pedro Barbosa.