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 existed since 1837 but had never been put into practice. Therefore, on June 9, 1904, following a proposal by Oswaldo Cruz, the government presented a bill to the Congress requesting the reestablishment of obligatory smallpox vaccination. The extremely rigid and severe provisions of this instrument terrified the people. Popular opposition against Cruz increased sharply and opposition newspapers started a violent campaign against this and the federal government in general. Members of the parliament and labor unions protested. An anti-vaccination league was organized. On November 10, the Vaccine Revolt exploded in Rio. Violent confrontations with the police ensued, with strikes, barricades,