People infected with schistosomes may present with a variety of clinical manifestations ranging from the relatively asymptomatic intestinal (INT) form to the hepatointestinal (HI) or hepatosplenic (HS) forms characterized by hepatomegaly and hepatosplenomegaly with severe portal hypertension, respectively. Flow cytometry analyses were used to evaluate the contribution of apoptosis in specific cell populations from schistosomiasis patients to the development of the different clinical forms of the disease. The results showed that cell death induced by combinations of specific antigen and cytokines corresponds with specific clinical presentations. It was shown that soluble egg antigen (SEA) increased the level of apoptosis only in T cells from INT patients. Stimulation with soluble lung worm antigen preparation (SLAP) did not induce significant differences in the levels of apoptosis in T cells from the patients with the different clinical forms of schistosomiasis. These results suggest for the first time that apoptosis plays an important role in the modulation of the anti-SEA response in INT patients.

Biomphalaria glabrata snails infected with Schistosoma mansoni were collected during consecutive seasons from a site in Brazil known to have a very high percentage of infected snails. Schistosoma mansoni cercariae from single snails were used to infect individual mice, and the recovered adult worms were genetically assessed using a mtVNTR marker. The number of unique parasite genotypes found per snail was compared to expected abundance values, based on the infection prevalence at the site, to determine the distribution of S. mansoni infections within the snail population. The observed distributions and those from previous studies were used to examine the relationship between schistosome prevalence and aggregation across a wide range of prevalence values. Our analysis showed that prevalence was inversely related to the degree of parasite overdispersion, and at high prevalence, S. mansoni infections were randomly distributed among snails.

Este estudo analisou a política de assistência a mulheres vítimas de violência no contexto familiar e assistidas no Programa Cidadania da Mulher, através de seus dois projetos: Centro de Apoio à Mulher - "Benvinda" e Casa Abrigo - "Sempre Viva", em Belo Horizonte, entre 1996-1998. Os dados foram adquiridos através de questionários semi-abertos e pré-testados, obtendo-se a representação mental das equipes técnica e de apoio (N=14), e de 10% de usuárias do Centro de Apoio no período de 1997-1998 (N=70); além de dados biológicos, psicossociais e das condições econômicas das usuárias entre 1996 e 1998 (N=1529); causas e tipos de violência. Os dados revelam que: a) a violência tem aspectos culturais, sociais e econômicas; b) estes indicadores descritos sugerem realizar estudos de casos analíticos dentro e fora do espaço familiar, de forma a aprofundar as questões aqui apresentadas; c) o programa é importante como política social de emergência por ser um serviço de referência para a população de Belo Horizonte e sua região metropolitana, além de cidades do interior do Estado, buscando maior integração entre as famílias destas com as instituições, na preservação dos direitos humanos e na construção da cidadania.

Foi avaliado o programa de controle da esquistossomose realizado em Taquaraçu de Minas, MG, entre 1985 e 1995. A medida de controle adotada foi a participação popular nas ações de controle: tratamento seletivo, saneamento e educação popular. A equipe de saúde local foi capacitada para gerenciar o programa, conforme proposta do SUS. O fornecimento de água potável foi oferecido a 97% das residências no núcleo do Município. Em 1995, foi realizada análise para identificação dos fatores de risco responsáveis pela manutenção da transmissão da esquistossomose. A prevalência da infecção entre 1985-1995 apresentou-se sete vezes menor, passando de 30,9% para 4,3%, respectivamente. A intensidade de infecção também sofreu significativa redução, passando de 91,2 ± 6,1 para 30,7 ± 2,5 (p = 0,00) no mesmo período. A municipalização desse programa de controle da esquistossomose através do SUS, usando-se um tratamento seletivo, fornecimento de água potável intradomiciliar com participação popular nas medidas de controle, seguido de atendimento da demanda espontânea, apresentou resultados duradouros, apontando a possibilidade de uso deste modelo para outras áreas endêmicas com características semelhantes.

In this study, the results obtained in a control programme of schistosomiasis in Ravena (Sabará, Minas Gerais) between 1980 and 1992 are evaluated. Control measures used in this programme were: specific treatment of the people infected with Schistosoma mansoni at four year-intervals (1980/84/88) and the supply of tap water to 90% of the residences in 1980. A significant reduction of the prevalence (36.7% to 11.5%, p < or = 0.05) and of the intensity of the infection (228.9 eggs per gram of feces (epg), s = 3.7 to 60.3 epg, s = 3.5, p < or = 0.05) was observed. No cases of the severe form of the disease were diagnosed in the area. Factors independently associated with the infection were in 1980 daily sand extraction and the lack of tap water in residences and in 1992 daily sand extraction and fishing and weekly swimming. Concluding, the supply of tap water together with quadrennial treatments significantly diminished both the prevalence and intensity of the S. mansoni infection, with the additional gain of persistent low indices even after four-year intervals between the treatments.

Applications of niclosamide at three-monthly intervals were undertaken for 14 years in foci of Biomphalaria glabrata in the water sources of Peri-Peri (Capim Branco, MG). All the residents of the area were submitted to an annual fecal examination (Kato/Katz) and those individuals eliminating Schistosoma mansoni eggs were treated with oxamniquine. A malacological survey was undertaken at three-monthly intervals by means of ten scoops with a perforated ladle each ten metres along the two banks of the ditches and streams of the region. Where snails were found, molluscicide was applied by means of dripping or aspersion using a 3 ppm aqueous suspension of niclosamide. Initially, a mean of 14.3% of snails in the region were found to be eliminating cercariae. Following the first four applications of molluscicide, this was reduced to 0.0% and maintained at about 1.5% throughout the program. Thus, there was a continued possibility of schistosomiasis transmission in the area and it was observed that the population of snails reestablished itself within three months of molluscicide application. The results obtained in this study do not encourage the continual use of niclosamide as the only method of control of schistosomiasis.

This study identified the role of biological and social determinants in the transmission of schistosomiasis mansoni in Ravena, Minas Gerais, Brazil, in 1980. This data was used to characterize the clinical and epidemiological profiles of the endemic desease in the population, allowing for the determination of the efficacy of the potable water supply and the specific treatment of those infected with S. mansoni. The district contains three locations, Ravenopolis, Ravena and Lavapes, where the prevalence of the endemic disease was, 20.1%, 42.6% and 63.9%, respectively. The prevalence in the district was statistically higher in men. The age brackets that displayed differences by gender were 10-14 and 15-19 years. Severity of infection was statistically different among individuals within the 10-14 year bracket in ali three locations, and in the 15-19 year bracket among individuals from Ravenopolis and Ravena. The hepatointestinal form was associated with age, and individuals under 15 years of age presented risk of infection 8.85 times higher than adults. Multivariable analysis of the factors involved in transmission of the disease showed that Lavapes was independently associated with infection. In that area, poor sanitary conditions and the proximity of houses to streams infested with S. marsoni cercariae facilitated infection of neighborhood women while performing domestic activities, as well as men digging sand from the streams for construction. These results show the focal nature of transmission of the endemic requiring specific intervention for effective control of disease.

This study shows the results of risk factor determination for infection with Schistosoma mansoni in endemic areas in Brazil. An association was observed between infection with S. mansoni and a number of general conditions: absence of drinking water in the home, low individual income, illiteracy, and residence in an endemic area for more than five years. In addition to these conditions there was also association with a number of habits (risk factors): agricultural and domestic activities in open water supplies, swimming, and fishing. Analysis of the general conditions that may determine these risk factors indicated that provision of drinking water in the home and access to treatment are basic measures that could be adopted in many cases in order to prevent or control the morbidity of the disease. The efficacy of the use of risk factor determination for indication of control measures for this disease is questioned.