The Estrada Real project and endemic diseases: the case of schistosomiasis, geoprocessing and tourism

Geographical Information System (GIS) is a tool that has recently been applied to better understand spatial disease distributions. Using meteorological, social, sanitation, mollusc distribution data and remote sensing variables, this study aimed to further develop the GIS technology by creating a model for the spatial distribution of schistosomiasis and to apply this model to an area with rural tourism in the Brazilian state of Minas Gerais (MG). The Estrada Real, covering about 1,400 km, is the largest and most important Brazilian tourism project, involving 163 cities in MG with different schistosomiasis prevalence rates. The model with three variables showed a R² = 0.34, with a standard deviation of risk estimated adequate for public health needs. The main variables selected for modelling were summer vegetation, summer minimal temperature and winter minimal temperature. The results confirmed the importance of Remote Sensing data and the valuable contribution of GIS in identifying priority areas for intervention in tourism regions which are endemic to schistosomiasis.

Host immune response to Toxoplasma gondii and Ascaris lumbricoides in a highly endemic area: evidence of parasite co-immunomodulation properties influencing the outcome of both infections

Toxoplasmosis and ascaridiasis evoke polar Th-1 and Th-2 host immune responses, respectively. A study to investigate the specific cytokine profile production by in vitro cultures of peripheral blood mononuclear cells from individuals living under precarious sanitary conditions in a highly endemic area for the parasites Toxoplasma gondii and Ascaris lumbricoides was conducted. High levels of both IFN-³ (Th-1) and IL-13 (Th-2) were observed in groups of co-infected individuals presenting toxoplasmic ocular lesions. Significantly lower IL-10 and TGF-² levels were produced by co-infected individuals in comparison with groups of individuals not infected with A. lumbricoides and either positive or negative for T. gondii living under good sanitary conditions (control groups). The possible influence of co-parasitism on the clinical presentation of ocular toxoplasmosis is discussed.

Re-evaluation of schistosomiasis mansoni in Minas Gerais, Brazil, III: "noroeste de Minas" mesoregion

Com o objetivo de verificar a possivel presenca da esquistossomose mansoni na mesorregiao Noroeste de Minas, area do estado de Minas Gerais ate o momento considerada indene para aquela parasitose, foi realizado um levantamento malacologico e um diagnostico coproscopico nos 13 municipios da mesorregiao. Foram coletados e examinados 3.627 planorbideos, identificados como Biomphalaria straminea em sete municipios (Unai, Bonfinopolis de Minas, Paracatu, Joao Pinheiro, Vazante, Lagamar e Lagoa Grande) e B. peregrina em um (Presidente Olegario). Os moluscos estavam negativos para S. mansoni. O exame coproscopico, pelo metodo Kato-Katz, foi realizado em 3.283 estudantes do primeiro grau da rede estadual de ensino. Quatro estudantes foram diagnosticados com esquistossomose nos municipios de Buritis, Formoso, Paracatu e Unai. Entretanto, nenhum dos casos foi considerado autoctone. Podemos concluir que a mesorregiao do Noroeste de Minas continua livre da esquistossomose, mas a presenca de hospedeiros intermediarios enfatiza a necessidade de implantacao de um programa de vigilancia epidemiologica na mesorregiao Noroeste de Minas...

Immunological profiles of patients from endemic areas infected with Schistosoma mansoni

Crude extracts of eggs (SEA) adult worms (SWAP) or cercariae (Cerc) have been used to stimulate Peripheral Blood Mononuclear cells (PBMC) and have provided rather distinct profiles of responses in different types of patients. In genenral it is clear that patients with early infections respond strongly to SEA while response to SWAP are developed more slowly. As infection progresses into the more chronic phases, a general pattern is seen whic leads to lower anti-SEA proliferative responses in the face of higher responses to SWAP and variable anti-cerc responsiveness. Cured not re-exposed patients express very high levels of anti-SEA proliferation. It has recently been seen that those individuals who live in endemic areas and have continued water contact, but are reapeatedly stool-negative (who are presumed to have self-cured or be putatively resistant; endemic normals) are strongly responsive to antigenic extracts, particularly to SEA. Furthermore, our results show that endemic normal individuals have significantly higher IFN gamma production upon PBMC stimulation with schistosome antigens than infected individuals. With the emergence of more studies it is becoming apparent that both the intensity and the prevalence of a given area may influence or shape the general responsiveness of the population under study