Resumo em Espanhol:

Triatoma infestans es el principal vector de la enfermedad de Chagas en Argentina. La experiencia adquirida en las campañas nacionales de este país ha demostrado que la fumigación de los domicilios para controlar los triatómidos es cara y difícil. Un método de control alternativo que podría ser un complemento práctico y barato de las medidas de control convencionales sería el empleo de telas impregnadas de piretroides. Los insectos que intentaran penetrar la tela o caminaran sobre ella en busca de comida serían intoxicados por la exposición al piretroide absorbido. En este estudio se utilizó un concentrado emulsionado del piretroide beta-cipermetrina [alfa-ciano-3-fenoxibencil-3- (2,2-diclorovinil) -2,2-dimetil-ciclopropano-carboxilato] para impregnar diferentes telas y después se investigó su eficacia y persistencia para matar a Triatoma infestans. Los bioensayos de laboratorio revelaron que, con una dosis de beta-cipermetrina de 0,2 g/m², el efecto insecticida era más duradero en la lana que en el algodón o el rayón. Ocho meses después de la impregnación, se registró una eficacia residual de 100% en la lana, de 80% en las telas de rayón y algodón y de 50% en las de rayón y poliéster. Además, las telas impregnadas de beta-cipermetrina presentaron mayor efecto repelente que las impregnadas de deltametrina o cipermetrina.En los estudios de campo, después de ser impregnadas in situ con una dosis de beta-cipermetrina de 1 g/m² y secadas, las telas fueron colocadas en el interior de las casas, debajo de los colchones o clavadas al techo. Estos estudios de campo demostraron que el método era muy eficaz para mantener los domicilios sin triatómidos durante al menos un año y que tenía un alto grado de aceptación por parte de los moradores.

Resumo em Inglês:

Triatoma infestans is the most important vector of Chagas disease in Argentina. Experiences from Argentine national campaigns have shown indoor spraying to control triatomine bugs is both expensive and difficult. An alternative control method may be the use of pyrethroid- impregnated fabrics (PIFs), which could be both a practical and cheap complement to conventional control measures. In this study, a formulation of emulsifiable concentrate of beta-cypermethrin [a-cyano-3-phenoxybenzyl-3- (2,2-dichlorovinyl) -2,2-dimethylcyclopropanecarboxilate] pyrethroid was used to impregnate different fabrics. The fabrics were then tested for their efficacy and persistence in killing Triatoma infestans. Insects attempting to penetrate or grasp the fabric in search of blood meals were poisoned by the exposure to the absorbed pyrethroid. Laboratory bioassays showed that the insecticidal effect of the PIFs with a dosage of 0.2 g/m² lasted longer on wool than on cotton or rayon. Eight months after impregnation, a residual efficacy of 100% was found for wool, 80% for rayon-cotton fabrics, and 50% for rayon- polyester fabrics. In addition, beta-cypermethrin-impregnated fabrics showed a better repellency effect than did fabrics impregnated with either deltamethrin or cypermethrin. For field trials, fabrics were impregnated either in the laboratory or "in situ" at a dosage of 1 g beta-cypermethrin/m² and then dried. The PIFs were placed inside homes, either under the roof or under the bed mattress. The field trials showed the PIF approach to be very effective in keeping dwellings free of triatomine bugs for at least one year and found a high degree of acceptability among the houses residents.

Resumo em Espanhol:

El asma es la enfermedad crónica más común en los niños y adolescentes y en los decenios más recientes se han registrado aumentos insólitos de su prevalencia en todas partes del mundo. Sin embargo, los estudios anteriores se han basado en distintos enfoques metodológicos, lo que dificulta hacer comparaciones entre los resultados. Ese factor estimuló a un grupo internacional de investigadores a elaborar un cuestionario estandarizado autoadministrable que permitiera llevar a cabo estudios internacionales en colaboración. Se creó así el instrumento utilizado en el International Study of Asthma and Allergies in Childhood (ISAAC) o Estudio Internacional del Asma y las Alergias en la Niñez. Durante el mes de abril de 1996 se realizó en la ciudad de Campos Gerais, Minas Gerais, Brasil, un estudio transversal para determinar la prevalencia en escolares del estertor sibilante y otras señales y síntomas relacionados con el asma bronquial utilizando el cuestionario elaborado para el ISAAC. Se seleccionaron de forma aleatoria simple 200 adolescentes de 13 a 14 años de edad matriculados en escuelas públicas del municipio, los cuales fueron entrevistados más tarde por dos estudiantes de medicina. La muestra estaba distribuida igualmente (50%) por sexo y edad. Se encontró que 28,5% de los escolares (IC95%: 22,3% a 35,3%) habían experimentado por lo menos un episodio de sibilancia en algún momento del pasado y que 6% de ellos (IC95%: 3,1 a 10,5%) habían tenido por lo menos una crisis asmática en los últimos 12 meses. Al comparar esos resultados con los obtenidos en ciudades brasileñas de mayor tamaño, se observa un aumento de las tasas de prevalencia que parece corresponder al aumento en densidad de la población y al grado de urbanización e industrialización de los municipios estudiados. Se refuerzan así las teorías que sostienen la existencia de una asociación entre el asma y los factores ambientales. De ello se desprende que es necesario hacer frente a ese trastorno como importante problema de salud pública en el Brasil.

Resumo em Inglês:

Asthma is the most common chronic disease among children and adolescents, and in recent decades dramatic increases in its prevalence have been reported around the world. However, previous studies have been based on a variety of methodological approaches, making it difficult to compare the results. That situation led a group of international researchers to prepare a standardized self-administered questionnaire to carry out cooperative international studies for the International Study of Asthma and Allergies in Childhood (ISAAC). During April 1996 a cross-sectional study using the ISAAC questionnaire was performed in the city of Campos Gerais, Minas Gerais, Brazil, to determine the prevalence of wheezing and other signs and symptoms related to bronchial asthma among schoolchildren. Two medical students interviewed a randomly selected sample of 200 adolescents 1314 years old registered in public schools in the city. The sample was equally distributed by sex and age. Of the schoolchildren, 28.5% (95% CI: 22.3%35.3%) had had wheezing or whistling in the chest at some point in the past. In the preceding 12 months, 6% of them (95% CI: 3.1%10.5%) had had at least one wheezing episode. A comparison of these results with ones from larger Brazilian cities studied showed that higher prevalence rates were associated with higher population densities and greater urbanization and industrialization. These results strengthen theories supporting an association between asthma and environmental factors. From this it follows that it is necessary to deal with asthma as an important public health problem in Brazil.

Resumo em Espanhol:

En 1977, Cuba informó de su primera epidemia de dengue, durante la cual se registraron más de 500 000 casos de fiebre del dengue causados por el serotipo 1 del virus. En 1981, se produjo una gran epidemia de dengue hemorrágico causada por el serotipo 2. Esa vez se notificaron 344 203 casos en total, 10 312 casos clínicos de dengue hemorrágico y 158 defunciones, de las cuales 101 correspondieron a niños. Por medio de una búsqueda activa con confirmación de laboratorio, en el municipio de Santiago de Cuba de la provincia del mismo nombre se detectó precozmente en enero de 1997 la reintroducción del dengue, específicamente del virus del tipo 2, genotipo Jamaica. En este trabajo se presentan los aspectos epidemiológicos de mayor interés referentes a esa epidemia. Se notificaron 3 012 casos confirmados por serología, 205 clasificados como fiebre hemorrágica del dengue/síndrome de choque del dengue, de los cuales 12 fallecieron (todos adultos). La infección secundaria por virus del dengue fue uno de los principales factores de riesgo en el desarrollo de dengue hemorrágico y 98% de los casos, así como 92% de los fallecidos, manifestaron una respuesta de tipo secundario. Por primera vez se observó la posibilidad de contraer dengue hemorrágico en personas con una infección secundaria de 16 a 20 años después de la primera infección. Pertenecer a la raza blanca fue otro factor de riesgo de importancia, tal como se había observado desde la epidemia de 1981. En la última epidemia se demostró que la llamada alerta de fiebre no es útil para la detección temprana de una epidemia. Las medidas tomadas por las autoridades sanitarias del país evitaron la extensión de la epidemia a otros municipios que estaban infestados por Aedes aegypti.

Resumo em Inglês:

A dengue epidemic that Cuba reported in 1997 registered more than 500 000 cases of dengue fever produced by viral serotype 1. In 1981, there was an epidemic of dengue hemorrhagic fever produced by serotype 2 of the virus. This time 344 203 clinical cases were reported, 10 312 of which were severe cases of hemorragic fever that led to 158 fatalities (101 of them among children). The reintroduction of dengue, and specifically of dengue viral serotype 2 (Jamaica genotype), was quickly detected in January 1997 through an active surveillance system with laboratory confirmation of cases in the municipality of Santiago de Cuba, in the province of the same name. The main epidemiological features of this outbreak are reported in this paper. A total of 3 012 cases were reported and serologically confirmed. These included 205 cases classified as dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS), 12 of which were case fatalities (all among adults). Secondary infection with dengue virus was one of the most important risk factors for DHF/DSS. Ninety-eight percent of the DHF/DSS cases and 92% of the fatal cases had contracted a secondary infection. It was the first time dengue hemorrhagic fever was documented as a secondary infection 16 to 20 years after initial infection. Belonging to the white racial group was another important risk factor for DHF/DSS, as had been observed during the 1981 epidemic. During the most recent epidemic it was demonstrated that the so called fever alert is not useful for early detection of an epidemic. Measures taken by the countrys public health officials prevented spread of the epidemic to other municipalities plagued by Aedes aegypti.

Resumo em Português:

As condições nutricionais da população brasileira melhoraram nas últimas 3 décadas. Mesmo assim, é pouco conhecido o papel da assistência oferecida por instituições públicas ou filantrópicas que atendem crianças pré-escolares de baixa renda e de maior risco nutricional. Visando avaliar o impacto nutricional do programa municipal de assistência alimentar em creches do município de Sorocaba, Estado de São Paulo, Brasil, realizou-se um estudo quase-experimental. Durante 1 ano, em quatro observações trimestrais, acompanhou-se a evolução no peso e altura de 444 crianças de 3 meses a 6 anos completos: 164 assistidas em uma creche (grupo de intervenção) e 280 não assistidas (grupo de não intervenção), residentes na área adstrita à creche porém não freqüentes à mesma, e identificadas em censo específico. Depois de colhidos termos de assentimento e executado um pré-teste, profissionais e alunos universitários entrevistaram as mães das crianças participantes no estudo, segundo técnicas e condições padronizadas. A antropometria foi realizada por dupla de investigadores, um deles sempre fixo na equipe, com equipamentos aferidos pela agência técnica regional. Avaliou-se a concordância entre a primeira observação e as observações subseqüentes, com estratificação da população em três grupos de escores z de peso para idade e peso por altura (tendo como referência as curvas do National Center for Health Statistics) verificados ao início do estudo e em três faixas etárias (menores de 24 meses, de 24 a 36 e maiores de 36 meses). Os grupos de intervenção e não intervenção foram semelhantes quanto às condições sócio-demográficas, exceto trabalho materno (as mães no grupo de intervenção trabalhavam fora com maior freqüência); foram significativamente distintos quanto à idade (mais velhas no grupo de intervenção), condições nutricionais (piores no grupo de intervenção) e prevalência de internação hospitalar anterior (maior no grupo de intervenção). Já nos primeiros 3 meses, 32% das crianças no grupo de intervenção migraram para estrato de status nutricional superior, enquanto no grupo de não intervenção apenas 13% apresentaram melhora. A diferença favorecendo o grupo de intervenção aumentou com a duração da intervenção e foi maior entre crianças mais velhas, permitindo concluir que a assistência na creche melhorou a nutrição das crianças atendidas.

Resumo em Inglês:

The nutritional status of Brazilians has improved over the last three decades. Still, little is known about the role played by nutritional assistance programs that public institutions and philanthropic organizations provide for low-income preschool children, who face greater nutritional risk. Therefore, we carried out a quasi-experimental study to evaluate the nutritional impact of the municipal preschool nutritional assistance program in the city of Sorocaba, São Paulo, Brazil. Over the course of a year, we performed quarterly measurements of weight and height on 444 children, whose ages ranged from 3 months to 6 years. In this population, 164 children were assisted by the preschool nutritional program (intervention group), and 280 children were not (nonintervention group). The children in the nonintervention group were identified by a special census for that purpose; they did not attend the preschool but lived nearby. After obtaining informed consent and carrying out a pretest, professionals and university students interviewed the mothers of the participating children, following standard techniques and conditions. Anthropometric measurements were done by teams of two interviewers, one of whom was a permanent member of the team, using equipment calibrated by the appropriate regional technical organization. The correspondence between the first measurement and subsequent measurements was evaluated by stratifying the population into three groups by z scores for weight-for-age and for weight-for-height, using U.S. National Center for Health Statistics reference curves. The z score groupings were established at the beginning of the study for three different age groups: younger than 24 months, 24-36 months, and older than 36 months. The two study groups (intervention and nonintervention) were similar sociodemographically, with the following exceptions: maternal employment (more of the mothers of children in the intervention group had jobs outside the home); age (children in the intervention group were significantly older); nutritional status (it was worse in the intervention group); and prevalence of hospital admittance (it was higher in the intervention group). After just the first three months of the study, 32% of the children in the intervention group had moved to a higher nutritional stratum, whereas only 13% of children in the nonintervention group had shown improved nutritional status. The difference in favor of the intervention group increased with the length of the intervention and was higher among older children. These results show that the preschool nutritional assistance program helped to improve the assisted childrens nutritional status.

Resumo em Espanhol:

En Honduras, la deficiencia de vitamina A (DVA) y la anemia ferropénica (AF) han sido problemas de salud pública reconocidos desde hace más de 30 años. Este trabajo, que se basa en la Encuesta Nacional de Micronutrientes de 1996 aplicada a 1678 niños de 12 a 71 meses de edad, presenta los resultados relacionados con la situación de la vitamina A y la prevalencia de anemia, así como con las concentraciones de vitamina A en el azúcar de consumo domiciliario. Según los resultados, 14% de los niños tenían deficiencia subclínica de vitamina A (retinol plasmático < 20myg/dL) y 32% estaban en riesgo de DVA (retinol en plasma 20-30myg/dL). Estos datos indican que en Honduras la DVA es un problema de salud pública de importancia moderada. Un análisis de regresión logística demostró que los niños de 12-23 meses de edad que no vivían en la zona rural del sur del país corrían el mayor riesgo de DVA subclínica. El tener una infección, reflejada en una elevación de las concentraciones de alfa-1-glucoproteína ácida, aumentó más de tres veces el riesgo de DVA subclínica. Los niños de hogares con agua extraída de ríos, arroyos o lagos mostraron un riesgo doble de DVA subclínica, en comparación con otros niños. Ese mismo riesgo doble se encontró en niños de hogares con el baño situado en el exterior. La VDA puede controlarse mediante la fortificación del azúcar. Las concentraciones de retinol en el azúcar de consumo domiciliario fueron de alrededor de 50% de las dictadas por la ley en Honduras. Hay una filtración importante de azúcar sin fortificar en el mercado, particularmente en la zona rural del norte, donde 33% de las muestras no tenían retinol. En general, 30% de los niños mostraron anemia (Hb < 11 g/dL). Un análisis de regresión logística reveló que los niños cuyos padres vivían con ellos pero no habían cursado por lo menos el cuarto año de primaria corrían un riesgo 33% mayor de tener anemia. La presencia de una infección y el tener insuficiencia de peso aumentaron el riesgo de anemia en 51 y 21%, respectivamente, lo cual indica que los proveedores de atención de salud no siempre saben que la anemia es un problema muy diseminado en niños pequeños ni tampoco saben diagnosticarla.

Resumo em Inglês:

Vitamin A deficiency (VAD) and iron deficiency anemia (IDA) have been recognized as public health problems in Honduras for over 30 years. This paper, based on the 1996 National Micro nutrient Survey on 1 678 children 1271 months of age, presents the results for vitamin A status and anemia prevalence, as well as the level of vitamin A in sugar at the household level. The results showed that 14% of the children were subclinically vitamin A deficient (plasma retinol < 20 µg/dL) and 32% were at risk of VAD (plasma retinol 2030 µg/dL). These data indicate that VAD is a moderate public health problem in Honduras. Logistic regression analysis showed that children 1223 months old living in areas other than the rural south of the country were at greatest risk of subclinical VAD. Infection, indicated by an elevated alpha-1-acid-glycoprotein level, increased the risk of subclinical VAD more than three-fold. Children from households that obtained water from a river, stream, or lake were at twice the risk of subclinical VAD compared with other children. That same doubled risk was found for children from a household with an outside toilet. VAD can be controlled by fortifying sugar. Retinol levels in sugar at the household level were about 50% of those mandated by Honduran law. There appears to be significant leakage of unfortified sugar into the market. This is particularly true in the rural north, where 33% of samples contained no retinol. Overall, 30% of children were anemic (Hb < 11 g/dL). Logistic regression analysis showed that children whose fathers lived with them but who had not attended at least grade 4 of primary school were at 33% greater risk of being anemic. Infection and being underweight increased the risk of being anemic by 51% and 21%, respectively. Many of the anemic children had not been given iron supplements, suggesting health care providers may not be aware that anemia is widespread among young children and/or know how to diagnose it.

Resumo em Espanhol:

Los estudios realizados en distintos países muestran diferencias importantes en el crecimiento de niños amamantados y alimentados con biberón; también se ha observado que los niños amamantados crecen más despacio a partir de los 2 ó 3 meses de edad, en comparación con el patrón de referencia NCHS/OMS (National Center for Health Statistics/Organización Mundial de la Salud). Estos resultados ponen en tela de juicio la equivalencia entre el crecimiento máximo y el óptimo. El presente trabajo tuvo como objetivo comparar el crecimiento en peso y longitud desde el nacimiento hasta los 24 meses, de un grupo de niños amamantado y otro alimentado con biberón, y describir el crecimiento del grupo de amamantados en relación con las normas NCHS/OMS y con el "conjunto mixto de datos de la OMS sobre niños amamantados" conocido como el 12-month breast-fed pooled data set. Con ese fin se analizaron datos procedentes del estudio Córdoba: lactancia, alimentación, crecimiento y desarrollo (CLACYD), en el cual se investigó a una cohorte representativa, estratificada por nivel social, de niños nacidos en 1993 en la ciudad de Córdoba, Argentina. Se analizaron los datos antropométricos de 74 niños amamantados durante el primer año de vida y 108 niños alimentados con biberón, que se registraron según técnicas estandarizadas al nacer y a los 6, 12 y 24 meses de edad. Los dos grupos eran homogéneos con respecto a la edad y la escolaridad de los padres, el estrato social, el orden de nacimiento, la talla materna, y el peso y la longitud al nacer. Las condiciones de vida (vivienda y saneamiento) eran más favorables en el grupo con alimentación artificial (P = 0,04). Los niños amamantados registraron menor peso y longitud a los 6, 12 y 24 meses que los alimentados con biberón y mostraron, con respecto a las pautas NCHS/OMS, una desaceleración del crecimiento a partir del segundo semestre, lo cual indica que las normas NCHS/OMS no son del todo adecuadas para evaluar el crecimiento de niños amamantados en nuestro medio (ciudad de Córdoba, Argentina). En los estratos sociales alto y medio, los valores del grupo con lactancia materna se asemejaron a los del "conjunto mixto de datos de la OMS", tanto en peso como en longitud. En los estratos bajo y muy bajo el peso fue satisfactorio, pero se observaron valores menores que los del "conjunto mixto" en lo que respecta a la longitud. La brecha de longitud observada para los estratos bajo y muy bajo no resta validez a la referencia del "conjunto mixto de datos de la OMS", sino que expresa las influencias de las condiciones de vida en el crecimiento lineal.

Resumo em Inglês:

Studies done in various countries show important differences in the growth of breast-fed and bottle-fed children. In addition, it has been found that breast-fed children grow more slowly beginning at the age of 2 or 3 months in comparison with the reference pattern of the U.S. National Center for Health Statistics (NCHS) and the World Health Organization (WHO). These results cast doubt on whether maximum growth is the same as optimal growth. The objective of this study was to compare the growth in weight and length, from birth to 24 months, for a group of children who were breast-fed with that of a group who were bottle-fed. The study was also intended to describe the growth of the breast-fed group in relation to the NCHS/WHO norms and a WHO "12-month breast-fed pooled data set." For this research, data were analyzed from the "Cordoba: lactation, feeding, growth, and development" study (or CLACYD study, for its Spanish-language acronym). That study looked at a representative cohort, stratified by social class, of children born in 1993 in the city of Cordoba, Argentina. The researchers analyzed anthropometric data on 74 children who were breast-fed during the first year of life and on 108 bottle-fed children. The data had been recorded, using standardized techniques, at birth and at 6, 12, and 24 months of age. Both groups were homogenous with respect to the age and schooling of the parents, social stratum, birth order, maternal height, and childs weight and length at birth. The living conditions (housing construction and availability of water and sewer services) were better among the group that was bottle-fed (P = 0.04). The breast-fed children had a lower weight and a shorter length at 6, 12, and 24 months than did the bottle-fed children. The breast-fed children also showed a slowing in growth with respect to the NCHS/WHO guidelines beginning in the second semester. This indicates that the NCHS/WHO norms are not totally adequate for evaluating the growth of breast-fed children in Cordoba, Argentina. In the high and middle social strata, the values for the breast-fed group resembled those for the WHO "pooled data set," both in weight and length. In the low and very low social strata, weight values were satisfactory, but the figures for length were less than those of the "pooled data set." The gap in length found among the low and very low social strata does not reduce the validity of the WHO "pooled data set" reference, but rather indicates the influence of living conditions on linear growth.

Resumo em Inglês:

This work describes the Regional Program on Bioethics of the Pan American Health Organization (PAHO)/World Health Organization (WHO), as well as the Programs main achievements. The Program was established in 1994 under a three-way agreement with the University of Chile and the Government of Chile. The Programs objective is to thematically link the work of the PAHO/WHO units and representatives in each country, in close cooperation with local public and private organizations. The Program investigates such subjects as the health of poor people, priority-setting, the growth of the private sector, salaries and incentives in the public sector, investment in hospitals, health sector reform, professional education, and working together for development. Finally, the direction and heading of the Program are presented. Its efforts are carried out as promotional, support, and service activities. These activities take the form of technical assistance for personnel training, public information dissemination, ethical situation analysis in research and services, reviewing curricula and professional practice standards, and advising on specific plans and programs.

Resumo em Espanhol:

En otros estudios se ha evaluado el menor riesgo de infecciones transmitidas por transfusión sanguínea que acarrea el tamizaje de anticuerpos contra los antígenos nucleares de la hepatitis B (anti-HBc), sumado a la prueba detectora de antígenos de superficie (HbsAg). No obstante, la mayoría de estos estudios se basaron en datos procedentes de zonas con baja endemicidad por hepatitis B o de bancos de sangre de países desarrollados, donde la mayoría de la sangre proviene de personas que han donado previamente. A fin de examinar los pros y los contras del tamizaje de anticuerpos anti-HBc en el Brasil, los autores describen los antecedentes y la interpretación de las pruebas de tamizaje para prevenir la hepatitis postransfusión. También presentan los datos sobre el tamizaje de la hepatitis B en todas las regiones del Brasil. No hay pruebas suficientes para suspender el tamizaje de los anticuerpos anti-HBc en el país. Debe darse alta prioridad a comparar el costo-efectividad de un marcador basado en la biología molecular con el de la actual prueba detectora de anticuerpos anti-HBc aplicada comúnmente, a fin de mejorar las medidas de tamizaje que garantizan la inocuidad de la sangre.