The ‘disease of Brazil’
Science, health and national debate on Chagas’ disease –
by Simone Petraglia Kropf
In April 1909, Carlos Chagas (1878–1934), a young researcher at the Oswaldo Cruz Institute (OCI) informed the scientific world about the discovery of a new disease in the small settlement of Lassance, in the Brazilian hinterlands.
It was caused by a protozoa (named by him Trypanosoma cruzi in honour of Oswaldo Cruz, the famous bacteriologist who founded the OCI) and transmitted by a triatomine insect known as barbeiro (barber, kissing or conenose bug), found in abundance in the mud and wattle huts typical of rural areas. Occurring at a time of dissemination of Mansonian tropical medicine, when institutions involved in this field (such as the OCI) were created in Brazil, Chagas’ ‘triple discovery’ of a vector, pathogen and human infection was celebrated as a ‘great feat’ of national science and as proof of science’s importance in the process by which Brazil would become a ‘civilised’ country.
Research into the new trypanosomiasis became the flagship of Cruz’s project to transform his institute – created in 1900 to produce serum and vaccine against bubonic plague – into a prestigious centre of experimental medicine engaged with Brazil’s public health concerns. In addition to making an original contribution to knowledge of the relationship between vectors, parasites and human diseases, it highlighted the possibility of associating the commitment to provide solutions to the country’s sanitary problems (thereby paving the way for modernisation) with the production of knowledge in line with the international agenda.
Right from his earliest studies, Chagas held that the illness was an endemic disease that dramatically threatened national progress by afflicting people across broad expanses of Brazil’s interior with physical and mental deterioration. According to him, the new trypanosomiasis was an infection that after a short-lived acute phase produced chronic neurological, cardiac and above all endocrine disturbances. He believed that in the locations where the T. cruzi infection was found the endemic goitre was not the same as occurred in Europe (which many attributed to the lack of iodine), but the result of the pathogenic action of the parasite on the thyroid. In addition to endemic goitre, the neurological disturbances attributed to T. cruzi pathogenic action – such as paralyses and mental retardation – assumed great importance in the characterisation of the disease as an important medical and social problem. In Chagas’ words, the disease was a “terrible scourge of a vast zone of the country, making a large amount of the population useless for vital activities, creating successive generations of inferior men, useless individuals, fatally consigned to a chronic morbid condition, to such a coefficient of inferiority that makes them inappropriate elements in the progressive evolution of the Patria”.
At a time in which the theme of ‘degeneration’ mobilised intellectual debate about the future and identity of the Brazilian nation, in public addresses to the principal Brazilian medical associations Chagas presented the reality of an unknown rural country, marked by poverty, disease and abandonment. The disturbing images of sick and incapacitated children and young people in miserable huts infested by barbeiros were the antithesis of ‘civilisation’, so feted in the city of Rio de Janeiro, the newly renovated capital of the Belle Époque and showroom of progress of the ‘new century’. The press emphasised the ‘horror’ of the medical and political élite that watched the young scientist. The disease discovered at Lassance was presented as the ‘disease of Brazil’.
At the same time that it became the emblem of a ‘sick country’, Chagas’ disease was also the icon of the science that revealed it and showed how it could be dealt with in the march of national progress. Chagas’ denunciation was accompanied by a new perspective for action: the country, traditionally seen as unviable owing to its tropical climate and the mixture of races, could in fact be ‘redeemed’ if the public authorities would confront the endemics that sapped the productivity of the majority of the population who lived in rural areas.
The idea that the diseases of the rural population were an obstacle to social and economic progress, requiring energetic action from the state, imprinted particular contours on tropical medicine in Brazil. Citing the Europeans concerned with fighting sleeping sickness in Africa for colonial interests, Chagas emphasised that the study of tropical pathology should be committed to the destiny of the nation itself: “it is the future of a great people that should be watched over”. If the sanitation of the capital – whose icons were Cruz’s 1903–09 campaigns against yellow fever, bubonic plague and smallpox – had been decisive for the ‘rehabilitation’ of the country, he warned that bringing public health to Brazil’s vast rural interior was an even bigger challenge.
With the intense nationalist debate during World War I – when issues such as the racial question, immigration, education and military recruitment were discussed in the context of identifying the ailments and the chances of national ‘regeneration’ – the process of the medical and social framing of Chagas’ disease gained new intensity. Together with other rural endemics it was the central theme of the so-called sanitation movement (movimento sanitarista), the most celebrated expression of which was the declaration in 1916 by well-known doctor Miguel Pereira that, despite current patriotic clamour, Brazil was actually an “enormous hospital”. The campaign united physicians, scientists, intellectuals and politicians around the idea that precarious health conditions, especially in the interior, were the principal hindrance to the country effectively becoming a nation. As a political movement it demanded that the state increase its public health interventions, especially in rural areas. Achieving great impact in the press, in intellectual spheres and in the National Congress, it was formally organised in 1918 as the Pro-Sanitation League of Brazil (Liga Pró-Saneamento do Brasil). The campaign resulted in a wide-ranging reform of the public health services upon the creation in January 1920 of the National Department of Public Health. Chagas, Director of the OCI since 1917, became the first director of this new institution.
Chagas’ disease was also a central theme in this nationalist debate. In 1922, the centenary of Brazilian independence, it became the subject of a public controversy in the National Academy of Medicine. Some physicians and scientists raised doubts about its clinical definition and social importance, arguing that the mistaken association with goitre (which was very common in Minas Gerais and other parts of the interior) had led to an exaggeration of the disease’s social impact. The lack of statistics and of an extensive epidemiological survey into the incidence of the disease reinforced this criticism, as did difficulties in proving the diagnosis of chronic cases. In contrast with the three million sufferers of the disease (15 per cent of the population) estimated by supporters of the sanitation movement, critics stated that the number of cases that had been parasitologically identified did not reach 40. According to these critics, the idea of a ‘sick Brazil’ would bring discredit to the country abroad and would drive away investment and immigrants.
Although the controversy was settled by a report that endorsed the scientific merits of Chagas’ work, an environment of doubts about the disease remained. The scientist, nevertheless, continued his studies. After 1916, when the first criticisms were launched by researchers in Argentina, he initiated an important process of reframing the clinical profile of trypanosomiasis, downplaying the primacy of thyroidal signs and reinforcing the weight of cardiac components. This process was intensified in the 1920s.
After his death in 1934, his disciples in the OCI – including his son, Evandro Chagas – continued the research, following important contributions made by Argentinean physicians, who identified some clinical signs of the acute phase of infection that enabled the diagnoses of hundreds of cases in several countries. In the 1940s, work carried out at an OCI research post established at Bambuí (Minas Gerais) provided new knowledge and agreement concerning the disease’s clinical definition and epidemiological importance; the correlation with goitre was disregarded and important advances in the diagnosis of the infection and in ECG techniques led to the recognition of the disease as essentially a chronic myocardiopathy.
In the context of World War II and the postwar period the question of development and the overcoming of the so-called ‘vicious cycle of poverty and disease’ assumed prominence in the international debate and in the Brazilian political agenda. Within this context, scientists mobilised their forces to disseminate knowledge about the disease and to interest various social groups in the topic. Their goal was to make it accepted that Chagas’ disease was a serious public health problem that compromised rural labour and consequently the expectations of rural modernisation aiming at supplying the expanding internal market, according to the economic model of ‘substitution of importations’. Trust in new technical resources to fight tropical diseases, such as DDT, reinforced scientific and political efforts against the disease. In 1950 the disease entered the Brazilian public health agenda for the first time: a prevention campaign with insecticide fumigation of human dwellings, carried out by the Ministry of Education and Health, was inaugurated in the city of Uberaba, a region of great importance to Minas Gerais modernisation.
Linking European theories on germs, vectors and so-called warm-climate diseases with the issues and challenges peculiar to a nation that wanted to be ‘civilised’ – and to the science that wanted to lead it – the path to scientific and social recognition of American trypanosomiasis was a long and winding one. Mobilising a variety of social actors, institutional spaces and spheres of social life, all under distinctive historical circumstances, it was a path that gives us an opportunity to reflect on the complex relations between science and society.
Simone Petraglia Kropf is a researcher at the Postgraduate Programme in the History of Sciences and Health, Casa de Oswaldo Cruz/Oswaldo Cruz Foundation, Rio de Janeiro, Brazil.