Health, a position corresponding to today's Brazilian Minister of Health. Using the Federal Serum Therapy Institute as a technical-scientific base, he embarked on a quick succession of important sanitation campaigns. His first challenge was a series of yellow fever endemics, which had earned Rio de Janeiro the sinister reputation of 'Foreigners' Grave'. Between 1897 and 1906, 4,000 European immigrants had died there from the disease. Cruz pursued the new technique of eradicating mosquitoes and their breeding grounds, fumigating houses, and isolation of the ill. There was opposition to the campaign by many, including physicians, the military, and the poor, but the campaign was successful. Cruz was initially successful in the sanitary campaign against the bubonic plague, to which end he used obligatory notification of cases, isolation of sick people, treatment with the sera produced at Manguinhos and extermination of the rats populating the city. Smallpox vaccination controversy He was not successful in implementing a widespread vaccination against smallpox, due to popular resistance to it. In 1904, a smallpox epidemic was threatening the capital. In the first five months of the year, more than 1,800 people had been hospitalized. A law imposing smallpox vaccination of children had 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, and shootings in the streets, as the population rose in protest against the government. On November 14, the cadets of the Military Academy joined the revolt, but were dispersed after intense shooting. The government declared a state of siege. On November 16, the uprising was controlled, but the obligatory vaccination was suspended. In 1908, a violent smallpox epidemic made the people rush en masse to the vaccination units. Some 9,000 people died. Cruz was vindicated and his merit recognized. Later work Among the international scientific community, his prestige was already uncontested. In 1907, on occasion of the 14th International Congress on Hygiene and Demography