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Biomedical subjects

F S Barbosa

Publications and source records attributed to F S Barbosa.

36 records · Page 2Linked to original sources
PubMed1975

Cross-sectional studies on Schistosoma mansoni infection in northeast Brazil.

Studies on the prevalence and morbidity of Schistosoma mansoni infection were carried out in selected areas of northeastern Brazil. The study revealed that both prevalence and morbidity rates were significantly higher in rural than in urban areas. No statistically significant differences in prevalence and morbidity were found in relation to sex. The age-specific prevalence curve was found to be of the usual shape found in highly endemic areas of the country: it reaches its peak in the 10-14 group, and slightly decreases in the older groups. Although it is generally admitted that hepatosplenic forms of the disease occur more frequently between 10 and 40 years of age, the present study has shown that the proportion of these severe cases increases with increase of age.

Adolescent↗
PubMedDate not supplied

Transmission of Schistosoma mansoni under experimental conditions using the bovine--Biomphalaria glabrata-bovine model.

Three calves experimentally infected with Schistosoma mansoni, and passing viable eggs in feces, as well as 5 normal calves (coming from a non-endemic area for schistosomiasis) kept as controls, were maintained in an enclosure (850 m2 in area). In this enclosure, a tank with water received 500 laboratory reared Biomphalaria glabrata. All the control calves were infected for a period ranging from 79 to 202 days after the beginning of the experiment, and afterwards presented viable S. mansoni eggs in feces. The mean worm recovery was 555. The snail population increased throughout the experimental period, showing a high number of B. glabrata infected with S. mansoni (42% on average). According to the present study, bovine has been suggested as having potentially a role in the maintenance of the life cycle of S. mansoni.

Animals↗
PubMedDate not supplied

Competitive interactions between species of freshwater snails. I. Laboratory studies: Ib. Comparative studies of the dispersal and the vagility capabilities of Biomphalaria glabrata and Biomphalaria straminea.

Experiments reported in the current paper, carried out under semi-field conditions created in the laboratory, have shown that B. straminea has competitive superiority when compared with B. glabrata. The former species has shown higher capabilities of both dispersal and vagility. In addition, B. straminea was able to compete successfully with B. glabrata.

Animals↗
PubMedDate not supplied

Competitive interactions between species of fresh-water snails. I. Laboratory. IC. Comparative survival of Biomphalaria glabrata and B. straminea kept out of water.

Biomphalaria glabrata and B. straminea were submitted to an out-door laboratory experiment for testing their comparative ability to resist desiccation. Results have shown that B. straminea is significantly higher resistant than B. glabrata. After five months under such distressing condition the survival ratios were: B. glabrata 8.1 per cent and B. straminea 18.4 per cent.

Adaptation, Physiological↗
PubMedDate not supplied

Determination and control of schistosomiasis.

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.(ABSTRACT TRUNCATED AT 250 WORDS)

Community Participation↗