Este artigo é parte de um estudo mais amplo que empregou abordagens epidemiológica e antropológica para procurar entender a produção e manutenção da esquistossomose em pequena comunidade de área endêmica de Pernambuco. No presente trabalho, realizamos um estudo de corte transversal para avaliação dos fatores de risco para esquistossomose, associando variáveis sócio-econômicas, sanitárias e comportamentais (quantificáveis), com a prevalência e intensidade da infecção. Uma análise estatística univariada selecionou três variáveis (faixa etária, escolaridade e número de contatos), que mostraram associação significativa com a positividade para S. mansoni. Os resultados da análise multivariada realizada a seguir permitiram a identificação dos fatores causais e das variáveis de confundimento, entre aquelas anteriormente selecionadas. O diagnóstico epidemiológico quantitativo é discutido criticamente, com embasamento no estudo qualitativo etnográfico, quanto às condições ambientais de risco (contaminação, transmissão) e práticas de risco (atividades econômicas e comportamentais).

This article is part of a larger study in which epidemiological and anthropological methods were used to help understand the production and maintenance of schistosomiasis in a small endemic area in Pernambuco State. A cross-sectional study identified several local risk factors for schistosomiasis, quantifying socioeconomic, sanitary, and behavioral variables and then relating them to the prevalence and intensity of schistosomiasis infection. Using univariate analysis, three variables (age group, schooling, and human/water contact) showed significant association with S. mansoni infection. Causal factors and confounding variables were identified through multivariate analysis. Quantitative epidemiological analysis is critically discussed regarding a qualitative ethnographic study in relation to environmental risk situations (contamination and transmission) as well as risk practices (economic and behavioral).

Este artigo é parte de um estudo mais amplo que empregou abordagens epidemiológica e antropológica para procurar entender a produção e manutenção da esquistossomose em pequena comunidade de área endêmica de Pernambuco. No presente trabalho, realizamos um estudo de corte transversal para avaliação dos fatores de risco para esquistossomose, associando variáveis sócio-econômicas, sanitárias e comportamentais (quantificáveis), com a prevalência e intensidade da infecção. Uma análise estatística univariada selecionou três variáveis (faixa etária, escolaridade e número de contatos), que mostraram associação significativa com a positividade para S. mansoni. Os resultados da análise multivariada realizada a seguir permitiram a identificação dos fatores causais e das variáveis de confundimento, entre aquelas anteriormente selecionadas. O diagnóstico epidemiológico quantitativo é discutido criticamente, com embasamento no estudo qualitativo etnográfico, quanto às condições ambientais de risco (contaminação, transmissão) e práticas de risco (atividades econômicas e comportamentais).

This article is part of a larger study in which epidemiological and anthropological methods were used to help understand the production and maintenance of schistosomiasis in a small endemic area in Pernambuco State. A cross-sectional study identified several local risk factors for schistosomiasis, quantifying socioeconomic, sanitary, and behavioral variables and then relating them to the prevalence and intensity of schistosomiasis infection. Using univariate analysis, three variables (age group, schooling, and human/water contact) showed significant association with S. mansoni infection. Causal factors and confounding variables were identified through multivariate analysis. Quantitative epidemiological analysis is critically discussed regarding a qualitative ethnographic study in relation to environmental risk situations (contamination and transmission) as well as risk practices (economic and behavioral).

This study focuses on the possibility of experimental hybridization among host snail species for Schistosoma mansoni in Brazil, with morphological characterization of the hybrids found. By using albinism as a genetic marker, intraspecific crossbreedings were performed between two strains of each species involved, in addition to interspecific crossbreedings; the only viable crossbreeding was between pigmented Biomphalaria glabrata (Paulista, PE) and albino B. tenagophila (Joinville, SC), with the formation of F1 and F2 generations. All offspring in F1 displayed black eyes and a renal ridge on the mantle, while F2 displayed dissociated morphological traits. With regard to reproduction, F1 was more efficient than F2. The experiment's results suggest post-zygotic reproductive isolation.

A esquistossomose continua a ser um problema de saúde pública no Nordeste do Brasil embora o emprego, em larga escala, da quimioterapia venha sendo apontado como um dos fatores responsáveis pela redução das formas graves. O Estado de Pernambuco vem apresentando taxas crescentes de infecção humana para esquistossomose com perfil epidemiológico de prevalências crônicas (até 80%) na região rural e casos recentes de infecção aguda no litoral. Discute-se a reprodução e expansão da esquistossomose a partir de uma concepção estrutural e histórica de causas, onde se inserem fatores não só de ordem biológica mas também sociais, políticos e culturais que vêm contribuindo para a formação dos quadros endêmicos: a forma de ocupação e do uso da terra, desemprego, desnutrição, migração e outros. Questionam-se as crescentes dificuldades para o controle da doença e o papel da investigação epidemiológica na compreensão da essência social do processo saúde/doença.

Schistosomiasis mansoni can be considered an important public health problem in Northeastern Brazil, in spite of the reduction in the prevalence of the hepatosplenic clinical forms which have been attributed to the large scale use of chemotherapy in this country. However, the rise in the prevalence rates and the spread of this endemic disease to new areas show that schistosomiasis is assuming its must cruel expression: less lethal but more greatly incapacitating in terms of irreversible physical and moral damage to human beings. The state of Pernambuco presents growing rates for schistosomiasis infection in humans. The epidemiological profile of this disease displays high and consistent prevalence rates (up to 80%) in rural areas, and new cases of acute infection on the coast, where schistosomiasis has recently been introduced. The reproduction and expansion of this endemic disease can be better understood on the basic of a conception of structural and historical causation. The disease construction process should be reconstructed in the light of biological as well as the social, political and cultural factors which are jointly responsible for the present endemic situation. Within that frame work, the historical and socio-economic features that interact with the parasite and give rise to the present proportions of the schistosomiasis epidemic in Pernambuco are discussed. The mode of occupation and use of the land, unemployment, under-nutrition, migration, etc., raise the question of the growing difficulties confronting the control of the disease, both in rural areas where populations are extremely mobile as well as in the poorly organized urban population. Epidemiological investigation is fulfithing its role in its attenpts to understand the complex relationships of an intrinsecally social nature of the health/disease process between health problems and the quality of life for the purpose of producing consistent disease control models.

A esquistossomose continua a ser um problema de saúde pública no Nordeste do Brasil embora o emprego, em larga escala, da quimioterapia venha sendo apontado como um dos fatores responsáveis pela redução das formas graves. O Estado de Pernambuco vem apresentando taxas crescentes de infecção humana para esquistossomose com perfil epidemiológico de prevalências crônicas (até 80%) na região rural e casos recentes de infecção aguda no litoral. Discute-se a reprodução e expansão da esquistossomose a partir de uma concepção estrutural e histórica de causas, onde se inserem fatores não só de ordem biológica mas também sociais, políticos e culturais que vêm contribuindo para a formação dos quadros endêmicos: a forma de ocupação e do uso da terra, desemprego, desnutrição, migração e outros. Questionam-se as crescentes dificuldades para o controle da doença e o papel da investigação epidemiológica na compreensão da essência social do processo saúde/doença.

Schistosomiasis mansoni can be considered an important public health problem in Northeastern Brazil, in spite of the reduction in the prevalence of the hepatosplenic clinical forms which have been attributed to the large scale use of chemotherapy in this country. However, the rise in the prevalence rates and the spread of this endemic disease to new areas show that schistosomiasis is assuming its must cruel expression: less lethal but more greatly incapacitating in terms of irreversible physical and moral damage to human beings. The state of Pernambuco presents growing rates for schistosomiasis infection in humans. The epidemiological profile of this disease displays high and consistent prevalence rates (up to 80%) in rural areas, and new cases of acute infection on the coast, where schistosomiasis has recently been introduced. The reproduction and expansion of this endemic disease can be better understood on the basic of a conception of structural and historical causation. The disease construction process should be reconstructed in the light of biological as well as the social, political and cultural factors which are jointly responsible for the present endemic situation. Within that frame work, the historical and socio-economic features that interact with the parasite and give rise to the present proportions of the schistosomiasis epidemic in Pernambuco are discussed. The mode of occupation and use of the land, unemployment, under-nutrition, migration, etc., raise the question of the growing difficulties confronting the control of the disease, both in rural areas where populations are extremely mobile as well as in the poorly organized urban population. Epidemiological investigation is fulfithing its role in its attenpts to understand the complex relationships of an intrinsecally social nature of the health/disease process between health problems and the quality of life for the purpose of producing consistent disease control models.

The subject of this conference reflects the scientific community's interest in seeking to understand the complex causal web whose various social, economic, and biological components interact in the production and reproduction of schistosomiasis and its control in relation to community participation. From the onset, the author stresses the impossibility of dealing separately with community participation, as if social components were just one more "weapon" in the arsenal for schistosomiasis control. This study begins with a brief historical review of the 71 years of control activities with this endemic disease, stressing the enormous efforts and huge expenditures in this field vis-à-vis the limited results, despite the extraordinary technological development of specific, classical control inputs such as new treatment drugs and molluscicides. The article then discusses the various strategies used in control programs, emphasizing ideological consistencies and contradictions. Interactions at the macro and micro levels are discussed, as are the determinants and risk factors involved in producing the disease's endemicity. Unequal occupation of space leaves the segregated portion of the population exposed to extremely favorable conditions for transmission of the disease. This raises the issue of how to control an endemic disease which is so closely linked to the way of life imposed on the population. The study challenges the classical control model and suggests an alternative model now undergoing medium-term investigation in the States of Espirito Santo, and Pernambuco, Brazil. The author concludes that we do not need new strategies, but a new control model, contrary to the prevailing classical model in both concept and practice. From the conceptual point of view, the new model mentioned above is different from others in that schistosomiasis control is seen from a social perspective stressing the population's accumulated knowledge in addition to the building of shared knowledge. The model's praxis has the following characteristics: (1) it is integrated with and financed by research agencies and health services; (2) it operates at the local health services level; (3) use of molluscicides has been eliminated; (4) emphasis is given to individual medical treatment and improvement of sanitary conditions.

Uma análise crítica sobre a situação da pobreza e da fome no período de 1977 a 1986 foi feita por J. Larry Brown et alii, nos EUA. Os autores indicam que as causas subjacentes deste fenômeno repousam sobre o aumento da desigual distribuição da riqueza naquele país e do enfraquecimento dos programas federais de assistência aos pobres. Comentários de outros sugerem que as causas mais profundas deste fenômeno têm raízes estruturais.

A critical analysis made on the current status (1977) to 1986) of the poverty and hunger in the USA is presented by J. Larry Brown et alii. The main conclusion is that the phenomenon is linked to the inequal national wealth distribution and the less emphasis given to the federal assistencial programs. Comments by others indicate that the phenomenon has deep economic structural roots.