The control of the schistosome-transmitting snail Biomphalaria glabrata by the plant Molluscicide Euphorbia splendens var. hislopii (syn milli Des. Moul): a longitudinal field study in an endemic area in Brazil.

Under laboratory conditions, latex from Euphorbia splendens has shown promise as a plant molluscicide for control of Biomphalaria species, intermediate hosts for Schistosoma mansoni. The purpose of this study was to evaluate its efficiency under field conditions. Application of filtered latex at 12 ppm to one stream in an endemic rural area in Minas Gerais state, Brazil, in September 1995, did result in a reduction in snail density as compared to an untreated stream but the snail population recovered quickly. However, two applications with a two-week interval of unfiltered E. splendens latex at 5 ppm in November 1996 in the same stream resulted in complete disappearance of B. glabrata and snails did not reappear until the 14th month after the applications. In the control stream, without treatment, the snails were found during all months. Laboratory studies confirmed that unfiltered latex is a more potent molluscicide than filtered latex. Considering the advantages of the latex such as its low toxicity to other aquatic animals and its photobiodegradability, as well as the simple method of application, this natural product is promising as an effective molluscicide.

Evaluation of the ZIG-ZAIDS game: a playful-educative resource for HIV/AIDS prevention.

This article presents the evaluation process for the ZIG-ZAIDS game, investigating the material's applicability in formal and informal educational contexts, i.e., how the game has been used by health professionals, parents, and the target population (pre-adolescents, or children over 9 years old). The study involved evaluation questionnaires sent to a list of schools and institutions using the game, plus interviews and visits to places where the game was used and tested with groups of students. It also includes an analysis of evaluation previously sent by the authors to people who had requested the game. The results showed that the population's level of information is more relevant than age in relation to the game's impact. Another important aspect relates to ZIG-ZAIDS' applicability to different situations: training of health and teaching professionals; activities with street children; municipal institutions and events, schools, companies, communities, and health care centers. In summary, ZIG-ZAIDS was found to be an entertaining, creative, and innovative alternative for providing information on AIDS and sexuality.

The molluscicidal activity of Crown of Christ (Euphorbia splendens var. hislopii) latex on snails acting as intermediate hosts of Schistosoma mansoni and Schistosoma haematobium.

The present study describes the action of the latex of Euphorbia splendens var. hislopii (E. milli) on species of the genus Bulinus and on Biomphalaria pfeifferi, intermediate hosts of schistosomiasis in Africa, and the Brazilian snails B. glabrata, B. tenagophila, and B. straminea, intermediate hosts of schistosomiasis in Brazil. The impact of the latex on the egg masses and embryos of B. glabrata was also evaluated. Using the standardized methodology of the World Health Organization for testing plant-derived molluscicides, we obtained a 90% lethal dose (LD90) ranging from 0.13 ppm for B. glabrata subjected to lyophilized latex to 4.0 ppm for B. pfeifferi tested with the natural latex. This material has proved to be one of the most potent and specific plant molluscicides discovered thus far, presenting advantages in terms of application so that it could be used in programs involving community participation in endemic areas in both Brazil and Africa.

An interactive perspective of health education for the tropical disease control: the schistosomiasis case.

Some municipalities in Brazil have been requesting orientation for the implementation of health education programs related to the control of schistosomiasis. This demand was based on experiences in the development of health education researches, strategies and materials for school-age children, involving the communities and secretaries of health and education. Motivated by this request and the recently implemented plan of health services (Unified Health System-Sistema Unico de Saúde-SUS) that gives autonomy to the municipalities to utilize health resources and services in Brazil, this paper presents an interactive perspective of planning health education research and programs. The purpose of this perspective is to stimulate a reflection on the needs and actions of institutions and people involved in health education research and/or programs to obtain sustainability, commitment and effectiveness--not only in the control of schistosomiasis, but also in the improvement of environmental conditions, quality of life and personal health. This perspective comprises interaction among three levels related to health education programs: the decision level, the executive level and the beneficiary level. The needs and lines of action at each of these levels are discussed, as well as the ways in which they can interact with each other. This proposal may lead to useful interactive ways of planing, organizing, executing and evaluating health education research and/or program, not only towards the prevention and control of the disease at stake, but also to promote health in general.

Evaluation of the molluscicidal properties of Euphorbia splendens var. hislopii (N.E.B.) latex: experimental test in an endemic area in the State of Minas Gerais, Brazil.

Following the positive results obtained regarding the molluscicidal properties of the latex of Euphorbia splendens that were corroborated in laboratory and field tests under restricted conditions, a field study was conducted in experimental streams located in an endemic area. After recording the average annual fluctuations of vectors in three streams, a solution of E. splendens latex at 12 ppm was applied in stream A, a solution of niclosamide at 3 ppm that was applied in stream B and a third stream (C) remained untreated for negative control. Applications of E. splendens and niclosamide resulted in a mortality of 100% among the snails collected in the streams A and B. No dead snails were found in the negative control stream. A monthly follow-up survey conducted during three consecutive months confirmed the return of vectors to both experimental streams treated with latex and niclosamide. This fact has called for a need to repeat application in order to reach the snails that remained buried in the mud substrate or escaped to the water edge, as well as, newly hatched snails that did not respond to the concentration of these molluscicides. Adults snails collected a month following treatment led us to believe that they had migrate from untreated areas of the streams to those previously treated.

Health education, public information, and communication in schistosomiasis control in Brazil: a brief retrospective and perspectives.

In recent years, the strategy for the control of schistosomiasis has placed increased emphasis on the role of health education, public information, and communication. This should, not only bring about specific changes in behavior aiming at disease prevention, but also stimulate participation of the community in health programs. Beyond this, it is desirable that both community members and researchers should seek better life conditions through a transformative social action. The present paper addresses these concerns; first, by critically reviewing some health education programs that were developed in Brazil, and, secondly, by analyzing and suggesting ways to improve this area.

PIP: As regards traditional information and participatory information, since the 1960s control campaigns of schistosomiasis in Brazil have emphasized the integration of health education with other measures. Practical educational actions were reflected in the work by Hollanda (1958) carried out in northeast Brazil. Her experience in prevention stressed the importance of the participation of the population in control programs. Garcia (1966) referred to economical factors affecting populations stricken by schistosomiasis. Educational actions in the 1970s and 1980s include the Project for the Environmental Control of Schistosomiasis (1970) carried out in Calciolandia with identification of knowledge modes of the population on schistosomiasis. A new model of fight against the disease with sanitary, medical, and educational components led to the creation in 1976 of the Ministry of Health's Special Program for Schistosomiasis Control with improvement of basic sanitation and health education. Mass media broadcasts were developed, and posters, folders, a documentary film, records, and cassettes were produced. New perspectives in health education, consideration of popular knowledge, and community participation revealed the inadequacy of traditional education in schistosomiasis prevention that requires community participation in information and communication processes. Health education for children entailed information and communication processes in school. High disease prevalence rates were found in the 6-20 year age groups, as well as higher resistance to treatment and higher rates of egg elimination when compared with adults. An amplified health education considers the individuals as an ecosystem where microorganisms live constituting the microbiota. Thus, it is vital to stimulate in children a positive self-image to view themselves in a wider context. Mass media and other material resources have been successful in achieving changes in smoking habits and nutrition, especially when professionals were involved in the preparation of programs. Choosing the best strategy means utilizing mass media, print materials, and drama as communication methods.

Perspectives of using Euphorbia splendens as a molluscicide in schistosomiasis control programs.

A total of 1,426 species of plants had been tested in order to find out a vegetal-derived molluscicide against the vectors of Schistosoma mansoni. Euphorbia splendens is one of the most promising molluscicides. In this article we briefly present the main aspects that have to be considered to use this plant as a molluscicide, which include some agricultural aspects and operational methods for application. This can be done by the extraction of the active principles (millaminas) present in the latex or in the raw juice obtained through total maceration of plants. The culture of E. splendens, which spreads out by vegetative sprouts, showed an annual average growth of 30 cm. After 1.5 years the average productivity of crude latex with a DL90 of 12 ppm concentration, was 1 liter by 8m2 by cultivated area. This amount is enough to treat a volume of water of 97,200 liters. A comparative analysis between the cost of snail control through synthetic molluscicides was carried out based upon the data presented by Jobim (1979) for six controlling methods in several countries, and some cost aspects for E. splendens. This analysis was done considering a geographic parameter expressed by the index cubic meters of treated habitat per square kilometer, from which we can obtain an estimate dimension of the geographic area to be cultivated with E. splendens necessary to treat the same volume of water treated by synthetic molluscicides.

Environmental and health education for school-age children: a transdisciplinary approach.

A brief critical analysis and suggestion for guidelines concerning environmental and health education in the elementary school are presented from the viewpoint of emerging pedagogic experiences and theoretical philosophical reflections. The major points discussed are: the importance of transdisciplinarity, the enhancement of participatory education where technical knowledge and popular wisdom meet, the planning and execution of concrete experiences which stimulate the sensations of pleasure and of admiration for nature and life, the analysis and the search for a solution to problems affecting the local reality of pupils without losing sight of global issues. A major priority is investment in teacher training, stimulating acquisition of knowledge through creative practice and formation of a critical awareness, essential for the school to clearly show its commitment to a future of greater social equality and harmony in our relationship to the environment.

[Health education in 1st grade public schools at the periphery of Belo Horizonte, MG, Brazil. I. Evaluation of the program relative to schistosomiasis]. / Educação em saúde em escolas públicas de 1. grau da periferia de Belo Horizonte, MG, Brasil. I - Avaliação de um programa relativo à esquistossomose.

A project has been developed with the objective of implanting and testing new materials and methodologies related to health education in first level schools. The present study is being performed in 4 public schools of a periferic area of Belo Horizonte, in two regions, one of high and another of low prevalence of schistosomiasis. The experimental design includes 2 experimental schools and 2 of control. The procedure involves interviews with teachers and students before and after the experimental test of the new materials; stool surveys and treatment of the sample of students. The results of the first interviews demonstrated that the knowledge of schistosomiasis is almost absent among teachers and students, although the prevalence of this disease has been maintained for a long time (70 years) in one of the regions studied (Gorduras). Out of 3131 students of the 4 schools, 67.5% were examined and 235 (11.0%) were tested positively. When the new students of 1989 were not included the prevalence decrease to 9.0% demonstrating a significative difference (X2 - 5%) in relation to 1988, showing the consequence of the treatment performed. Comparing the 2 schools of high prevalence, the decrease of prevalence of the experimental one is higher than the control. Therefore, in relation to the schools of low prevalence, the same has not happened. Thus, it is only possible to suggest an initial effect of the educative strategy and the decreases of the prevalence in the schools of high prevalence. In relation to the knowledge about the disease transmission, the students from the experimental schools presented a significative increase of correct answers in 1989 than the control ones.

[Health education in 1st grade public schools at the periphery of Belo Horizonte, MG, Brazil. II. Knowledge, opinion and prevalence of helminthiasis among students and teachers]. / Educação em saúde em escolas públicas de 1. grau da periferia de Belo Horizonte, MG, Brasil. II - Conhecimentos, opiniões e prevalencia de helmintíases entre alunos e professores.

As part of a wide ranging project concerning education and health, aiming both to update and develop new materials and methods for 1st Grade schools, the present study investigated the state of knowledge and prevalence of helminthic diseases in school populations. Interviews and parasitological exams undertaken in four schools (two experimental and two controls) on the outskirts of Belo Horizonte showed: a. that both teachers and pupils have little information concerning helminthic diseases as well as incorrect notions and ignorance of the mechanisms of transmission; b. high prevalence in the school: 69.0% and 76.0% (Bairro Gorduras) and 46.0% and 24.0% (Vale do Jatobá and Barreiro de Cima) in the first year of study (1988). Comparing the four schools, there is a direct relationship between the living conditions of the pupils and the indices of prevalence. Considering the fact that such helminthic diseases are known to have been present for a long time, it is a striking how removed the school is from the problems and realities of its pupils.

Evaluation of the molluscicidal property of Euphorbia splendens var. Hispolii (N.E.B.) (Euphorbiaceae): 2. Investigation in lotic habitat

The latex of Euphorbia splendens var. hispolii in 12 ppm concentration (12 mg/l) caused 100% mortality for a Biomphalaria tenagophila population in a lotic habitat after 9 hr of dripfeed application. For sentinel snails, in cages placed at the water surface and buried under 0.10 m, the mortality rates varied with the distance from the application point and were: 100% (0 m); 92.6% (50 m) and 94.7% (100). No lethal effects were observed for the other living species in this habitat (Pomacea haustrum and Poecilia reticulata)

Evaluation of temporal, seasonal and geographic stability of the molluscicidal property of Euphorbia splendens latex.

Laboratory tests with aqueous solutions of Euphorbia splendens var. hislopii latex have demonstrated seasonal stability of the molluscacidal principle, with LD90 values of 1.14 ppm (spring), 1.02 ppm (fall), 1.09 ppm (winter), and 1.07 ppm (summer) that have been determined against Biomphalaria tenagophila in the field. Assays on latex collected in Belo Horizonte and Recife yielded LD90 values similar to those obtained with the reference substance collected in Rio de Janeiro (Ilha do Governador), demonstrating geographic stability of the molluscacidal effect. The molluscacidal action of aqueous dilutions of the latex in natura, centrifuged (precipitate) and lyophilized, was stable for up to 124 days at room temperature (in natura) and for up to 736 days in a common refrigerator at 10 to 12 degrees C (lyophilized product). A 5.0 ppm solution is 100% lethal for snails up to 13 days after preparation, the effect being gradually lost to almost total inactivity by the 30th day. This observation indicated that the active principle is instable. These properties together with the wide distribution of the plant, its resistance and adaptation to the tropical climate, its easy cultivation and the easy obtention of latex and preparation of the molluscicidal solution, make this a promising material for large-scale use in the control of schistosomiasis.

Evaluation of the molluscicidal properties of Euphorbia splendens var. hislopii (N. E. B.) (Euphorbiaceae)--1. Experimental test in a lentic habitat.

The latex of Euphorbia splendens var. hislopii, at concentrations between 5 to 12 mg/l, kills 100% of the population of Biomphalaria glabrata in a lentic habitat, after 24 h. The lyophilized latex, stocked for 18 months, killed only 34.2% of the snails, at the concentration of 5 mg/l, and 96.0% at 12 mg/l. No lethal effect was observed among Pomacea haustrum exposed to the same concentrations of the molluscicide.

[The concept of disease and preservation of health of a population of teachers and first grade students]. / Conceito de doença e preservação da saúde de população de professores e escolares de primeiro grau.

In view of the fact that information about how teachers and students conceptualize illness and their ideas of health preservation have important implications of health education, these two concepts were studied in a sample population of teachers and pupils, of a school course of up to 14-year-olds, representative of the northern area of Rio de Janeiro County. The results obtained are discussed in the light of two approaches: (a) the contributions from the cognitive theories of concept formation; (b) the influence of the social context in the acquisition, development and characterization of the concepts studied. This study was undertaken with a view to contributing to the field of health education by means of critical review and reflection on the concept of the health illness process in schools, in view of the complex and multidimensional aspects involved in the process.

Toxicological study of the molluscicidal latex of Euphorbia splendens: irritant action on skin and eye.

Aqueous solutions of the molluscicidal latex of Euphorbia splendens are irritant to the rabbit eye in concentrations higher than 0.35% and to the rabbit skin in concentrations higher than 0.5%. Although this irritant potential does not preclude its use as a molluscicide, special precautions are recommended for handling and application of the product and the hazard of skin tumor-promoting potential should be carefully investigated before its use for schistosomiasis vector control.

Evaluation of the genotoxic activity and acute toxicity of Euphorbia splendens latex, a molluscicide for the control of schistosomiasis.

1. The latex of Euphorbia splendens var. hislopii has a molluscicidal action at low concentration (LD90 less than 1.5 ppm or 1.5 micrograms/ml) against the vector snails of schistosomiasis. 2. In the present study, the latex in natura or after lyophilization was submitted to the Ames test and the chromotest to evaluate genotoxicity, to the Microtox System to determine acute toxicity, and to the Chinese hamster ovary cell assay (CHO) to measure cytotoxicity. 3. The latex had no mutagenic activity in the presence or absence of S9 toward the TA98 and TA100 strains of Salmonella typhimurium (Ames test) at concentrations up to 200 microliters/plate (in natura) and of 200 micrograms/plate (lyophilized). The lyophilized latex had no genotoxic activity (Chromotest) and no acute toxic effect on Photobacterium phosphoreum at concentrations up to 445 micrograms/ml, whereas the sample in natura had a toxic effect with an EC50 of 148,000 microliters/l (or ppm). In the CHO/cytotoxicity assay, the lyophilized latex had no cytotoxic effect in quantities up to 200 micrograms. 4. The latex was found to have no acute toxicity or mutagenic activity at the concentrations of 10 to 12 micrograms/ml (or ppm) that are being proposed for molluscicidal use in the field.

Zigzaids--an educational game about AIDS for children.

In spite of the progress made in treating the different opportunistic illness in HIV syndrome, prevention remains the only real answer we have in stopping the spread of this disease. Programmes using new, innovative and interactive materials are necessary to reach a maximum number of people.

Toxicological study of the molluscicidal latex of Euphorbia splendens: irritant action on skin and eye

Aqueous solutions of the molluscicidal latex of Euphorbia splendens are irritant to the rabbit eye in concentrations higher than 0.35% and to the rabbit skin in concentrations higher than 0.5%. Although this irritant potential does not proclude its use as a molluscicide, special precautions are recommended for hanbdling and application of the product and the hazard of skin tumor-promoting potencial should be carefully investigated before its use for schistosomiasis vector control.