Voronoi distance based prospective space-time scans for point data sets: a dengue fever cluster analysis in a southeast Brazilian town

<p>Abstract</p> <p>Background</p> <p>The Prospective Space-Time scan statistic (PST) is widely used for the evaluation of space-time clusters of point event data. Usually a window of cylindrical shape is employed, with a circular or elliptical base in the space domain. Recently, the concept of Minimum Spanning Tree (MST) was applied to specify the set of potential clusters, through the Density-Equalizing Euclidean MST (DEEMST) method, for the detection of arbitrarily shaped clusters. The original map is cartogram transformed, such that the control points are spread uniformly. That method is quite effective, but the cartogram construction is computationally expensive and complicated.</p> <p>Results</p> <p>A fast method for the detection and inference of point data set space-time disease clusters is presented, the Voronoi Based Scan (VBScan). A Voronoi diagram is built for points representing population individuals (cases and controls). The number of Voronoi cells boundaries intercepted by the line segment joining two cases points defines the Voronoi distance between those points. That distance is used to approximate the density of the heterogeneous population and build the Voronoi distance MST linking the cases. The successive removal of edges from the Voronoi distance MST generates sub-trees which are the potential space-time clusters. Finally, those clusters are evaluated through the scan statistic. Monte Carlo replications of the original data are used to evaluate the significance of the clusters. An application for dengue fever in a small Brazilian city is presented.</p> <p>Conclusions</p> <p>The ability to promptly detect space-time clusters of disease outbreaks, when the number of individuals is large, was shown to be feasible, due to the reduced computational load of VBScan. Instead of changing the map, VBScan modifies the metric used to define the distance between cases, without requiring the cartogram construction. Numerical simulations showed that VBScan has higher power of detection, sensitivity and positive predicted value than the Elliptic PST. Furthermore, as VBScan also incorporates topological information from the point neighborhood structure, in addition to the usual geometric information, it is more robust than purely geometric methods such as the elliptic scan. Those advantages were illustrated in a real setting for dengue fever space-time clusters.</p

Medication use among children 0-14 years old: population baseline study

OBJECTIVE: Determine the prevalence of medication use in children and adolescents in 20 municipalities of Vale do Jequitinhonha, Minas Gerais-Brazil, showing the main groups and variables that may have influenced use. METHODS: Descriptive population-based survey sample of 555 interviews, selected by simple random cluster sampling of 137 census tracts. Inclusion criteria were age &#8804; 14 years, mandatory interview with the legal guardians, and regardless of having received medications. Regarding the usage pattern, participants were divided into two groups: consumption and non-consumption of drugs. A descriptive analysis of the variables and tests of association were performed. RESULTS: The prevalence of drug consumption was 56.57%, and 42.43% showed no consumption. The use of medicinal plants was 72.9% for drug users and 74.3% for non-users. The health conditions for consumption were cough, common cold, flu, nasal congestion or bronchospasm (49.7%), fever (5.4%), headache (5.4%), diarrhea, indigestion, and abdominal colic (6.7%). In cases of self-medication, 30.57% of the drugs were given by the mother, and 69.42% were prescription drugs. Self-medication was prevalent using paracetamol (30.2%), dipyrone (20.8%), and cold medicine (18.8%). There was increased use of analgesics/antipyretics, followed by respiratory medications, systemic antibiotics, histamine H1 antagonists, and vitamins/antianemics. CONCLUSIONS: The prevalence of drugs use in children was high, indicating the need for formulating educational programs aiming at the awareness of caregivers regarding rational use

Análise da influência de determinados fatores sobre o estado nutricional de crianças residentes em comunidades rurais de Diamantina-mg

Breast milking is worldwide considered one of the fundamental pillars for health promotion and protection. In spite of its generally recognized importance, rates of breast milking alone are still low in most countries, and its lasting is unsatisfactory. This study aimed to evaluate the nutritional condition of 5-9 years old children in correlation with the variables duration of breast milking alone, family income, mother�s literacy and number of family members. The study was performed with children dwelling in nine rural communities from Diamantina-MG, Brazil. In order to evaluate the nutritional condition, it was utilized anthropometric measures of weight and height. Indexers were constructed and cut-off values were established in accordance to the curves of the National Center for Health Statistic - NCHS. The variables were obtained by means of a questionnaire developed by the authors. A number of 149 children were randomly choosen (n value for a significance of 0.05 and test power of 0.9). Results showed that 76.87% of the children presented normal nutritional conditions, while 19.73% were in nutritional risk since they were underweight and presented evidences of malnutrition, whereas 3.4% were overweight. Data indicated that the nutrition risk were predominant for children who were not exclusively breastmilked until the 6th month. It was also observed that the nutritional condition is influenced by the number of family members and by mother�s literacy. Therefore, rural populations, mainly composed by low-income families with impaired healthy assistance, are being exposed to nutritional risk, whereas some reverting intervention is requiredO aleitamento materno é considerado um dos pilares fundamentais para a promoção e proteção da saúde em todo o mundo. Apesar do amplo reconhecimento de sua importância, na maioria dos países as taxas de amamentação exclusiva ainda são baixas e a duração, insatisfatória. O presente estudo buscou caracterizar o estado nutricional de crianças na faixa etária entre cinco e nove anos e comparar com as variáveis tempo de amamentação exclusiva, renda familiar, escolaridade da mãe e número de membros na família destas crianças, residentes em nove comunidades rurais de Diamantina - MG, Brasil. Para avaliação do estado nutricional, foram utilizadas medidas antropométricas de peso e estatura, construídos índices e estabelecidos pontos de corte segundo as curvas do National Center for Health Statistic - NCHS. Para obtenção das variáveis foi utilizado um questionário desenvolvido pela equipe. Cento e quarenta e nove crianças foram sorteadas aleatoriamente (n calculado para atender aos critérios: significância 0,05 e poder do teste 0,9). Os resultados mostraram que 76,87% das crianças encontrava-se eutrófica, 19,73% encontrava-se em risco nutricional (baixo peso e desnutridas) e 3,4% encontrava-se com sobrepeso. Os dados revelaram que em crianças que não foram amamentadas exclusivamente até os seis meses de idade, houve predomínio de risco nutricional. Observou-se ainda que o estado nutricional é afetado pelo número de membros na família e escolaridade da mãe. O risco nutricional está atingindo populações rurais, formadas principalmente por famílias de baixa renda e com dificuldades de acesso a serviços de saúde, tornando necessárias ações para reverter tal quadro

ANÁLISE DA INFLUÊNCIA DE DETERMINADOS FATORES SOBRE O ESTADO NUTRICIONAL DE CRIANÇAS RESIDENTES EM COMUNIDADES RURAIS DE DIAMANTINA-MG doi: http://dx.doi.org/10.5892/RUVRV.91.89106

O aleitamento materno é considerado um dos pilares fundamentais para a promoção e proteção da saúde em todo o mundo. Apesar do amplo reconhecimento de sua importância, na maioria dos países as taxas de amamentação exclusiva ainda são baixas e a duração, insatisfatória. O presente estudo buscou caracterizar o estado nutricional de crianças na faixa etária entre cinco e nove anos e comparar com as variáveis tempo de amamentação exclusiva, renda familiar, escolaridade da mãe e número de membros na família destas crianças, residentes em nove comunidades rurais de Diamantina - MG, Brasil. Para avaliação do estado nutricional, foram utilizadas medidas antropométricas de peso e estatura, construídos índices e estabelecidos pontos de corte segundo as curvas do National Center for Health Statistic - NCHS. Para obtenção das variáveis foi utilizado um questionário desenvolvido pela equipe. Cento e quarenta e nove crianças foram sorteadas aleatoriamente (n calculado para atender aos critérios: significância 0,05 e poder do teste 0,9). Os resultados mostraram que 76,87% das crianças encontrava-se eutrófica, 19,73% encontrava-se em risco nutricional (baixo peso e desnutridas) e 3,4% encontrava-se com sobrepeso. Os dados revelaram que em crianças que não foram amamentadas exclusivamente até os seis meses de idade, houve predomínio de risco nutricional. Observou-se ainda que o estado nutricional é afetado pelo número de membros na família e escolaridade da mãe. O risco nutricional está atingindo populações rurais, formadas principalmente por famílias de baixa renda e com dificuldades de acesso a serviços de saúde, tornando necessárias ações para reverter tal quadro