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Distribution Theory of Some Nonparametric Statistics via Finite Markov Chain Imbedding TechniqueLee, Wan-Chen 16 April 2014 (has links)
The ranking method used for testing the equivalence of two distributions has been studied for decades and is widely adopted for its simplicity. However, due to the complexity of calculations, the power of the test is either estimated by normal approximation or found when an appropriate alternative is given. Here, via a Finite Markov chain imbedding (FMCI) technique, we are able to establish the marginal and joint distributions of the rank statistics considering the shift and scale parameters, respectively and simultaneously, under two continuous distribution functions. Furthermore, the procedures of distribution equivalence tests and their power functions are discussed. Numerical results of a joint distribution of two rank statistics under the standard normal distribution and the powers for a sequence of alternative normal distributions with mean from -20 to 20 and standard deviation from 1 to 9 and their reciprocals are presented. In addition, we discuss the powers of the rank statistics under the Lehmann alternatives.
Wallenstein et. al. (1993, 1994) discussed power via combinatorial calculations for the scan statistic against a pulse alternative; however, unless certain proper conditions are given, computational difficulties exist. Our work extends their results and provides
an alternative way to obtain the distribution of a scan statistic under various alternative conditions. An efficient and intuitive expression for the distribution as well as the power of the scan statistic are introduced via the FMCI. The numerical results of the exact power for a discrete scan statistic against various conditions are presented. Powers through the finite Markov chain imbedding method and a combinatorial algorithm for a continuous scan statistic against a pulse alternative of a higher risk for a disease on a specified subinterval time are also discussed and compared.
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Multiscale Scanning in Higher Dimensions: Limit theory, statistical consequences and an application in STED microscopyKönig, Claudia Juliane 26 June 2018 (has links)
No description available.
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Univariate and Multivariate Surveillance Methods for Detecting Increases in Incidence RatesJoner, Michael D. Jr. 02 May 2007 (has links)
It is often important to detect an increase in the frequency of some event. Particular attention is given to medical events such as mortality or the incidence of a given disease, infection or birth defect. Observations are regularly taken in which either an incidence occurs or one does not. This dissertation contains the result of an investigation of prospective monitoring techniques in two distinct surveillance situations. In the first situation, the observations are assumed to be the results of independent Bernoulli trials. Some have suggested adapting the scan statistic to monitor such rates and detect a rate increase as soon as possible after it occurs. Other methods could be used in prospective surveillance, such as the Bernoulli cumulative sum (CUSUM) technique. Issues involved in selecting parameters for the scan statistic and CUSUM methods are discussed, and a method for computing the expected number of observations needed for the scan statistic method to signal a rate increase is given. A comparison of these methods shows that the Bernoulli CUSUM method tends to be more effective in detecting increases in the rate. In the second situation, the incidence information is available at multiple locations. In this case the individual sites often report a count of incidences on a regularly scheduled basis. It is assumed that the counts are Poisson random variables which are independent over time, but the counts at any given time are possibly correlated between regions. Multivariate techniques have been suggested for this situation, but many of these approaches have shortcomings which have been demonstrated in the quality control literature. In an attempt to remedy some of these shortcomings, a new control chart is recommended based on a multivariate exponentially weighted moving average. The average run-length performance of this chart is compared with that of the existing methods. / Ph. D.
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Condições socioeconômicas e ambientais associadas à hanseníase na Bahia, Brasil / Socio-economic and environmental effects influencing the development of leprosy in Bahia, BrazilMiranda, William Cabral de 19 June 2015 (has links)
Introdução: A hanseníase, doença infecciosa crônica, causada pelo bacilo Mycobacterium leprae, tem seu mecanismo de transmissão não totalmente esclarecido. A transmissão ativa pode estar associada a movimentos migratórios, condições sociais ou outras fontes de infecção (como a manutenção do bacilo no ambiente). Objetivos: Descrever o padrão espacial do risco relativo da hanseníase em menores de 15 anos no estado da Bahia; identificar possíveis agrupamentos espaciais e investigar a possível associação entre o risco relativo da hanseníase e fatores socioeconômicos e ambientais. Metodologia: Este estudo ecológico utilizou dados do Sistema de Informação de Agravos de Notificação (SINAN) de 2005 a 2011, do Censo Demográfico do Instituto Brasileiro de Geografia e Estatística de 2010, da Federação das Indústrias do Estado do Rio de Janeiro, Informações Demográficas e Socioeconômicas do Departamento de Informática do SUS, bases cartográficas digitais de dados ambientais do IBGE e bases cartográficas digitais do estado da Bahia e estados vizinhos. Os riscos relativos por município foram padronizados pela covariável gênero. A análise de varredura espacial com o programa SaTScan permitiu verificar a existência de agrupamentos espaciais do tipo alto e/ou baixo. O segundo estágio da análise consistiu em verificar a possível associação entre risco relativo da hanseníase como variável dependente e variáveis socioeconômicas e ambientais como explicativas, através de análises de regressão hierárquica multivariada não espacial e espacial, de acordo com quadro conceitual definido previamente. Resultados: Durante o período de estudo foram notificados 1.674 casos, que representam 7,87% dos casos totais. As taxas em menores de 15 anos, padronizadas por gênero, diminuiu de 0,89/10.000 em 2005 para 0,57 em 2011. A estatística de varredura espacial identificou 4 agrupamentos de risco alto e 6 de risco baixo. No modelo de regressão hierárquica, o risco relativo foi associado positivamente com porcentagem de corpos dágua, Índice de Gini, porcentagem de população urbana, número médio de moradores em domicílios particulares permanentes, e negativamente com o número de residentes nascidos na Bahia. Conclusão: Este estudo mostrou que a hanseníase ainda está ativa no Nordeste do Brasil, principalmente em ambientes urbanos. Embora o risco relativo da hanseníase tenha diminuído, ele ainda permanece muito alto. Migrações de assentamentos rurais para as cidades, bem como mais pessoas vivendo em domicílios e desigualdades sociais são resultados de um processo histórico no nordeste do Brasil, que dão suporte para a continuidade do processo de transmissão da doença. A associação entre o risco relativo da hanseníase e corpos dágua na escala geográfica proposta, indica que a hipótese que associa a M. leprae e ambientes úmidos ainda não pode ser descartada. / Background: Leprosy is a chronic infectious disease caused by the bacillus Mycobacterium leprae. Its mechanism of transmission has not been completely understood. The active transmission may be associated with people migration, social conditions or other sources of infection (such as maintenance of bacilli in the environment). Objectives: To describe the spatial pattern of the relative risk of leprosy in children under 15 years old in the State of Bahia; to identify possible spatial clusters and to investigate the possible association between the relative risk of leprosy with socioeconomic and environmental factors. Methods: This ecological study used data from the Brazilian Disease Notification System (Sistema Nacional de Informação de Agravos de Notificação SINAN) for the studied period of 2005 to 2011; Instituto Brasileiro de Geografia e Estatstica (IBGE 2011), Department of Data and Information Technology (Informações Demográficas e Socioeconômicas do Departamento de Informática do SUS DATASUS, 2010) and the Federation of Industries of the State of Rio de Janeiro FIRJAN (2010), Cartographic base of municipalities in Bahia and surrounding States corresponded to the shape files from the Brazilian Demographic Census. Relative risks were calculated accounting for the respective covariate gender. The spatial scan analysis with SaTScan program allowed to verify the existence of high and/or low spatial clusters. The second stage of the analysis consisted of verifying possible associations between the relative risks of leprosy as a dependent variable, and socio-economic and environmental variables as independent. This was performed using a multivariate regression analysis according to a previously defined conceptual framework. Results: During the study period, 1,674 cases were reported, representing 7.87% of the total cases. Overall rates have decreased from 0.88/10 000 in 2005 to 0.52 in 2011. Spatial scan statistics identified 4 high-risk and 6 low-risk clusters. In the regression model, after allowing for spatial dependence, relative risks were associated with higher percentage of water bodies, higher Gini index, higher percentage of urban population, larger average number of dwellers by permanent residence and smaller percentage of residents born in Bahia. Conclusions: This study showed that leprosy is still active in the Northeast of Brazil, especially in urban environments. Although relative risks of leprosy in Bahia have been decreasing, they remain very high. Migration of rural settlements to the cities, more people living in households and social inequalities are the result of a historical process in northeastern Brazil, that support the continuity of the disease transmission process. The association between relative risks of leprosy and water bodies in the proposed geographic scale indicates that hypothesis linking M. leprae and humid environments cannot be discarded.
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Condições socioeconômicas e ambientais associadas à hanseníase na Bahia, Brasil / Socio-economic and environmental effects influencing the development of leprosy in Bahia, BrazilWilliam Cabral de Miranda 19 June 2015 (has links)
Introdução: A hanseníase, doença infecciosa crônica, causada pelo bacilo Mycobacterium leprae, tem seu mecanismo de transmissão não totalmente esclarecido. A transmissão ativa pode estar associada a movimentos migratórios, condições sociais ou outras fontes de infecção (como a manutenção do bacilo no ambiente). Objetivos: Descrever o padrão espacial do risco relativo da hanseníase em menores de 15 anos no estado da Bahia; identificar possíveis agrupamentos espaciais e investigar a possível associação entre o risco relativo da hanseníase e fatores socioeconômicos e ambientais. Metodologia: Este estudo ecológico utilizou dados do Sistema de Informação de Agravos de Notificação (SINAN) de 2005 a 2011, do Censo Demográfico do Instituto Brasileiro de Geografia e Estatística de 2010, da Federação das Indústrias do Estado do Rio de Janeiro, Informações Demográficas e Socioeconômicas do Departamento de Informática do SUS, bases cartográficas digitais de dados ambientais do IBGE e bases cartográficas digitais do estado da Bahia e estados vizinhos. Os riscos relativos por município foram padronizados pela covariável gênero. A análise de varredura espacial com o programa SaTScan permitiu verificar a existência de agrupamentos espaciais do tipo alto e/ou baixo. O segundo estágio da análise consistiu em verificar a possível associação entre risco relativo da hanseníase como variável dependente e variáveis socioeconômicas e ambientais como explicativas, através de análises de regressão hierárquica multivariada não espacial e espacial, de acordo com quadro conceitual definido previamente. Resultados: Durante o período de estudo foram notificados 1.674 casos, que representam 7,87% dos casos totais. As taxas em menores de 15 anos, padronizadas por gênero, diminuiu de 0,89/10.000 em 2005 para 0,57 em 2011. A estatística de varredura espacial identificou 4 agrupamentos de risco alto e 6 de risco baixo. No modelo de regressão hierárquica, o risco relativo foi associado positivamente com porcentagem de corpos dágua, Índice de Gini, porcentagem de população urbana, número médio de moradores em domicílios particulares permanentes, e negativamente com o número de residentes nascidos na Bahia. Conclusão: Este estudo mostrou que a hanseníase ainda está ativa no Nordeste do Brasil, principalmente em ambientes urbanos. Embora o risco relativo da hanseníase tenha diminuído, ele ainda permanece muito alto. Migrações de assentamentos rurais para as cidades, bem como mais pessoas vivendo em domicílios e desigualdades sociais são resultados de um processo histórico no nordeste do Brasil, que dão suporte para a continuidade do processo de transmissão da doença. A associação entre o risco relativo da hanseníase e corpos dágua na escala geográfica proposta, indica que a hipótese que associa a M. leprae e ambientes úmidos ainda não pode ser descartada. / Background: Leprosy is a chronic infectious disease caused by the bacillus Mycobacterium leprae. Its mechanism of transmission has not been completely understood. The active transmission may be associated with people migration, social conditions or other sources of infection (such as maintenance of bacilli in the environment). Objectives: To describe the spatial pattern of the relative risk of leprosy in children under 15 years old in the State of Bahia; to identify possible spatial clusters and to investigate the possible association between the relative risk of leprosy with socioeconomic and environmental factors. Methods: This ecological study used data from the Brazilian Disease Notification System (Sistema Nacional de Informação de Agravos de Notificação SINAN) for the studied period of 2005 to 2011; Instituto Brasileiro de Geografia e Estatstica (IBGE 2011), Department of Data and Information Technology (Informações Demográficas e Socioeconômicas do Departamento de Informática do SUS DATASUS, 2010) and the Federation of Industries of the State of Rio de Janeiro FIRJAN (2010), Cartographic base of municipalities in Bahia and surrounding States corresponded to the shape files from the Brazilian Demographic Census. Relative risks were calculated accounting for the respective covariate gender. The spatial scan analysis with SaTScan program allowed to verify the existence of high and/or low spatial clusters. The second stage of the analysis consisted of verifying possible associations between the relative risks of leprosy as a dependent variable, and socio-economic and environmental variables as independent. This was performed using a multivariate regression analysis according to a previously defined conceptual framework. Results: During the study period, 1,674 cases were reported, representing 7.87% of the total cases. Overall rates have decreased from 0.88/10 000 in 2005 to 0.52 in 2011. Spatial scan statistics identified 4 high-risk and 6 low-risk clusters. In the regression model, after allowing for spatial dependence, relative risks were associated with higher percentage of water bodies, higher Gini index, higher percentage of urban population, larger average number of dwellers by permanent residence and smaller percentage of residents born in Bahia. Conclusions: This study showed that leprosy is still active in the Northeast of Brazil, especially in urban environments. Although relative risks of leprosy in Bahia have been decreasing, they remain very high. Migration of rural settlements to the cities, more people living in households and social inequalities are the result of a historical process in northeastern Brazil, that support the continuity of the disease transmission process. The association between relative risks of leprosy and water bodies in the proposed geographic scale indicates that hypothesis linking M. leprae and humid environments cannot be discarded.
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Systèmes d’Information Géographique et Lien Environnement – Santé (SIGLES) : contribution au développement d'outils cartographiques d'aide à la décision face aux risques sanitaires liés à l'environnement / Geographic Information Systems and Environmental HealthOccelli, Florent 24 September 2014 (has links)
La question des inégalités environnementales et sociales de santé (IESS) à l’échelle des territoires est rapportée à deux dimensions cumulatives : un niveau d’exposition des populations à un environnement de vie dégradé et un niveau de vulnérabilité face à ces facteurs de risques, capables d’affecter la santé. Ces travaux de recherche concernent les Systèmes d’Information Géographique (SIG) appliqués au domaine de la santé environnementale. Ils ont pour objectifs généraux la caractérisation de la qualité des milieux environnementaux et l’évaluation des IESS. L’atteinte de ces objectifs passe préalablement par la récolte, la genèse et la mise en forme de bases de données environnementales spatialisées. Ces bases issues de la surveillance physico-chimique et de la biosurveillance des milieux sont ensuite cartographiées à l'aide des outils SIG, notamment les méthodes géostatistiques d’interpolation spatiale. En parallèle, les disparités spatiales d'incidence de pathologies sont étudiées grâce à des méthodes de cartographie des maladies (Ratios d'Incidence Standardisés : SIR) et de détection de clusters atypiques d'évènements (statistique de scan) mises en œuvre sur la base de registres de maladies. Finalement des études écologiques spatialisées sont élaborées afin de rapprocher les cartographies environnementales générées aux indicateurs sanitaires et socio-économiques. Ces travaux s’attachent à répondre à la question « les populations présentant un état de santé dégradé vivent-elles dans un environnement dégradé ? » Ce questionnement a été étudié à travers trois axes de recherche. Le premier concerne la caractérisation de l’imprégnation de l’environnement par les éléments traces métalliques (ETM) et l’évaluation des IESS à fine résolution sur trois bassins de vie de la région Nord-Pas de Calais (NPdC). Cette recherche est menée à partir de mesures d’imprégnations biologiques réalisées à la fois chez des lichens épiphytes et chez l’Homme et d’un indicateur de défaveur localisé. Les ETM mesurés ont été considérés de manière individuelle, mais également de manière globale à travers le développement d’un indice intégré multimétallique, afin d’exprimer le niveau d’imprégnation général par plusieurs métaux. Des inégalités environnementales ont été mises en évidence à l’échelle des quartiers du bassin de Dunkerque. Nos résultats supposent également l’implication de l’environnement dans l’imprégnation des populations pour certains ETM.Dans le deuxième axe, nous avons mis en évidence des disparités spatiales d’incidence de l’insuffisance rénale chronique terminale entre les cantons du NPdC et souligné l’implication du statut socio-économique dans l’apparition de ces disparités, contrairement à d’autres facteurs (diabète, maladies cardiovasculaires, pratiques médicales). Seule une partie des disparités de cette pathologie est aujourd’hui expliquée. Il est donc nécessaire de poursuivre sur le rôle des contaminants de l’environnement. Enfin, le troisième axe s’intéresse à l’analyse spatiale et spatio-temporelle de contaminations des eaux souterraines par les ETM, en vue d’identifier de potentiels facteurs de risques environnementaux des maladies inflammatoires chroniques de l’intestin. La réalisation de ces travaux s’appuie sur plusieurs collaborations établies avec le Réseau REIN, le Registre EPIMAD et des équipes de recherche (EA4483 et EA2694 Université Lille 2, TVES EA4477 ULCO).A la suite de ces travaux de thèse, les perspectives de recherche sont de poursuivre le développement d’indicateurs intégrés d’exposition aux contaminations multiples des milieux environnementaux. Les résultats montrent également un manque de renseignement des bases de données environnementales par rapport aux registres de santé. Un travail est donc nécessaire afin de définir le contenu de ces bases, nécessaire pour caractériser la qualité des milieux et faciliter l’étude de l’interaction de l’Homme avec son environnement. / Environmental and social inequalities in health (ESIH) over territories are related to two cumulative dimensions: populations exposed to their living poor quality environment and the vulnerability of these populations to the environmental risk factors, which can affect health. This research deals with the Geographic Information Systems (GIS) applied to the field of environmental health. General purposes are the characterization of environmental media quality and the assessment of ESIH.Achieving these objectives requires a first step of harvest, genesis and formatting spatialized environmental databases. Such data are resulting from physico-chemical monitoring and biomonitoring. They were then mapped using GIS tools, including geostatistical spatial interpolation methods. On the over hand, spatial variability in the incidence of diseases were investigated using disease mapping methods (Standardized Incidence Ratios: SIR) and the detection of atypical clusters of events (scan statistics), which are based on disease registries. Finally, geographical ecological studies are developed to associate the environmental maps generated to health and socio-economic status. Thus, this work aims to answer the question \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\"do people with poor state of health live in a poor quality environment?\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\" This question has been studied through three main researches.The first relates the characterization of trace elements burdens in the environment and the assessment of ESIH on neighborhood scale, over three territories in the Nord-Pas de Calais (NPdC) region. This research is conducted from measurements of biological burdens performed both in epiphytic lichens and humans and from a localized index of deprivation. The measured metals were considered individually, but also holistically by developing an integrated multimetallic index, in order to describe the general status of environmental pollution by metals. Environmental inequalities were observed on neighborhood scale in Dunkerque. Our results assume that trace elements burdens in populations are affected by environmental burdens.In our second research we revealed spatial disparities in the incidence of end stage renal disease (ESRD) on small area in the NPdC. Unlike other factors (diabetes, cardiovascular disease, medical practices), we highlighted the role of socio-economic status in the occurrence of such disparities. Only a part of the ESRD variability is currently explained. It is therefore necessary to focus on the environmental hypothesis.The third research focuses on the spatial and spatio-temporal analysis of groundwater contamination by trace elements, in order to identify potential environmental risk factors in the incidence of chronic inflammatory bowel disease.This work is based on several collaborations with the REIN network, the EPIMAD registry, and several research teams (EA4483 and EA2694 Université Lille 2, TVES EA4477 ULCO).Following this thesis, the research prospects are to pursue the development of integrated indicators to assess population exposure to the multiple environmental media contamination. The results also indicate a lack of information in environmental databases compared to health registries. A work is thus needed to define the content of such databases. These are necessary to characterize the environmental quality and to help the assessment of interaction between the populations and their living environment.
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Dinâmica espacial e contingências socioambientais da hanseníase no Estado do Maranhão: avaliação de riscos e vulnerabilidade em áreas hiperendêmicas / Spatial dynamics and socio and environmental contingencies of leprosy in Maranhão state: risk assessment and vulnerability in hyperendemic areasRangel, Mauricio Eduardo Salgado 22 September 2016 (has links)
A hanseníase, doença crônica estigmatizante com potencial de causar danos neurológicos, resulta da infecção pelo Mycobacterium leprae. Análises epidemiológicas atuais têm utilizado ferramentas clínicas e de análise espacial para o mapeamento dos principais focos de ocorrência de doenças e de áreas de alto risco. Analisar os municípios maranhenses quanto à distribuição dos casos de hanseníase torna-se uma ferramenta a mais na prevenção e controle da Hanseníase no estado por inúmeros fatores: comporta-se como área hiperendêmica de hanseníase; apresenta fluxo migratório intenso com outras cidades de forma interestadual; e tem grandes contrastes sociais marcados por pouca, ou nenhuma, infraestrutura básica em algumas áreas dos vários municípios deste. Objetivos: Analisar a distribuição espaço-temporal da hanseníase para o estado do Maranhão, no período de 2001 a 2013. Identificar a ocorrência de agrupamentos espaços-temporais de provável alta transmissão (risco) e verificar se há associação dessa distribuição de taxas de detecção de risco relativo (RR) da doença com as variáveis do contexto geográfico como socioeconômicas e ambientais. Metodologia: A fonte de coleta dos dados clínicos e epidemiológicos foi o Sistema de Informação Nacional de Agravos Notificáveis do Ministério da Saúde e dos dados demográficos, ambientais e bases cartográficas digitais do Instituto Brasileiro de Geografia e Estatística. Foi adotada uma abordagem ecológica sobre tendências dos padrões espaçostemporais de transmissibilidade, com utilização dos métodos: varredura espacial (scan), para a identificação dos agregados (clusters) de risco, considerando o modelo de distribuição de probabilidade Discreto de Poisson; Estimador Bayesiano Empírico para a suavização local de taxas, a partir de informações de municípios vizinhos tendo como estratégia de construção o critério da contiguidade; regressão múltipla espacial considerando uma modelagem com distribuição de Poisson no contexto Bayesiano, levando em conta a dependência espacial, com o propósito de avaliar a relação entre a ocorrência da variável dependente com as variáveis demográficas, socioeconômicas e ambientais. Resultados: A taxa média de detecção foi de 6,73 casos por 10.000 hab., com 53.826 casos notificados no período. O estudo revelou que a distribuição dos casos de sexo masculino (57,75%) apresentou maior proporção em relação ao feminino (42,25%), havendo predominância da doença na faixa etária >15 anos (89,87%). A alta ocorrência na classificação operacional multibacilar (60,10%) é um forte indicativo decorrente do longo período de incubação da doença somado ao não diagnóstico precoce. A análise da distribuição dos agregados espaciais identificou 14 (7 de risco alto e 7 de risco baixo) e 6 (3 de risco alto e 3 de risco baixo) agrupamentos espaciais, considerando-se 10% e 50% da população em risco, respectivamente, em áreas com taxas de detecção alta e que possuem baixa qualidade de vida. O estimador Bayesiano empírico local possibilitou gerar índices corrigidos e com menores instabilidades. A análise de regressão múltipla espacial mostrou que as variáveis índice Gini, bioma predominante cerrado/caatinga e percentual de população urbana tiveram associação positiva e significativa para explicar o risco relativo (RR) no estado do Maranhão. Conclusões: O estudo mostrou que existem aglomerados com elevado risco para transmissão da hanseníase no estado do Maranhão. A associação entre o risco relativo da hanseníase e o percentual de população urbana indica que a hipótese que associa o M. leprae e a população que vive em condições de acentuada desigualdade socioeconômica ainda é forte. Essa hiperendemicidade pode demonstrar que o crescimento da população urbana é um preditor de incidência da hanseníase, face à urbanização descontrolada e ao fluxo de migrantes advindos de diferentes espaços rurais. Foi possível identificar áreas prioritárias para implementação de programas eficazes de controle de hanseníase no estado do Maranhão. / Leprosy, a chronic stigmatizing disease with the potential to cause neurological damage resulting from infection by Mycobacterium leprae. Current epidemiological studies have used clinical and spatial analysis for mapping of the main occurrence of disease outbreaks and high-risk areas. Analyze the municipalities of Maranhão state regarding the distribution of leprosy cases becomes another tool in the prevention and control of leprosy in the state by numerous factors like behaves as hyper-endemic area of leprosy; It presents intense migration to other interstate cities; and has great social contrasts marked by little or no basic infrastructure in some areas of several municipalities.. Objectives: To analyze the spatiotemporal distribution of leprosy in the Maranhão state, from 2001 to 2013. To identify the spatiotemporal clusters occurrence of probable high transmission (risk) and check for association of this distribution of relative risk (RR) detection rates of the disease with the variables of geographic context as socioeconomic and environmental. Methodology: Clinical and epidemiological data was obtained from the Ministry of Healths Disease Reporting System and demographic data, environmental and digital cartographic bases were obtained from the Brazilian Geography and Statistics Institute. An ecological approach to trends transmissibility of spatiotemporal patterns, using the methods: spatial scan to identification the clusters of risk, considering the Discrete Poisson probability distribution model; empirical Bayesian method was applied for local rate flattening, using data from municipalities having as building strategy the criterion of contiguity; ecological regression modeling with considering a Poisson distribution in the Bayesian context, taking into account the spatial dependence, in order to evaluate the relationship between the occurrence of the dependent variable with demographic, socioeconomic and environmental variables. Results: The mean detection rate was 6.73 cases per 10,000 inhabitants, with 53,826 reported cases. The study revealed that the distribution of male cases (57.75%) showed a predominance over female (42.25%), with predominance of the disease in the age group upper than 15 years (89.87%). The high occurrence in operational classification multibacillary (60.10%) is a strong indication due to the long incubation period of the disease added to no early diagnosis. The analysis of the distribution of spatial clusters identified 14 (7 high risk and 7 low risk) and 6 (3 high risk and 3 low risk) spatial clusters, considering 10% and 50% of the population at risk in areas with high detection rates and which have low quality of life. Local empirical Bayes estimator allowed to generate fixed and minor instabilities indexes. The best results of modeling to spatial multiple regression analysis for the relative risk (RR) presented for the variables Gini index, cerrado/caatinga biome and percentage of urban population. Conclusions: The study showed that there are clusters at high risk for transmission of leprosy in the Maranhao state. The association between the relative risk of leprosy and the percentage of urban population indicates that the hypothesis that associates M. leprae and the population living in severe socioeconomic inequality is still strong. This hyperendemicity can demonstrate that the growth of the urban population is a predictor incidence of leprosy due to uncontrolled urbanization and the influx of migrants coming from different rural areas.It was possible to identify priority areas for implementation of effective leprosy control programs in the Maranhão state.
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Dinâmica espacial e contingências socioambientais da hanseníase no Estado do Maranhão: avaliação de riscos e vulnerabilidade em áreas hiperendêmicas / Spatial dynamics and socio and environmental contingencies of leprosy in Maranhão state: risk assessment and vulnerability in hyperendemic areasMauricio Eduardo Salgado Rangel 22 September 2016 (has links)
A hanseníase, doença crônica estigmatizante com potencial de causar danos neurológicos, resulta da infecção pelo Mycobacterium leprae. Análises epidemiológicas atuais têm utilizado ferramentas clínicas e de análise espacial para o mapeamento dos principais focos de ocorrência de doenças e de áreas de alto risco. Analisar os municípios maranhenses quanto à distribuição dos casos de hanseníase torna-se uma ferramenta a mais na prevenção e controle da Hanseníase no estado por inúmeros fatores: comporta-se como área hiperendêmica de hanseníase; apresenta fluxo migratório intenso com outras cidades de forma interestadual; e tem grandes contrastes sociais marcados por pouca, ou nenhuma, infraestrutura básica em algumas áreas dos vários municípios deste. Objetivos: Analisar a distribuição espaço-temporal da hanseníase para o estado do Maranhão, no período de 2001 a 2013. Identificar a ocorrência de agrupamentos espaços-temporais de provável alta transmissão (risco) e verificar se há associação dessa distribuição de taxas de detecção de risco relativo (RR) da doença com as variáveis do contexto geográfico como socioeconômicas e ambientais. Metodologia: A fonte de coleta dos dados clínicos e epidemiológicos foi o Sistema de Informação Nacional de Agravos Notificáveis do Ministério da Saúde e dos dados demográficos, ambientais e bases cartográficas digitais do Instituto Brasileiro de Geografia e Estatística. Foi adotada uma abordagem ecológica sobre tendências dos padrões espaçostemporais de transmissibilidade, com utilização dos métodos: varredura espacial (scan), para a identificação dos agregados (clusters) de risco, considerando o modelo de distribuição de probabilidade Discreto de Poisson; Estimador Bayesiano Empírico para a suavização local de taxas, a partir de informações de municípios vizinhos tendo como estratégia de construção o critério da contiguidade; regressão múltipla espacial considerando uma modelagem com distribuição de Poisson no contexto Bayesiano, levando em conta a dependência espacial, com o propósito de avaliar a relação entre a ocorrência da variável dependente com as variáveis demográficas, socioeconômicas e ambientais. Resultados: A taxa média de detecção foi de 6,73 casos por 10.000 hab., com 53.826 casos notificados no período. O estudo revelou que a distribuição dos casos de sexo masculino (57,75%) apresentou maior proporção em relação ao feminino (42,25%), havendo predominância da doença na faixa etária >15 anos (89,87%). A alta ocorrência na classificação operacional multibacilar (60,10%) é um forte indicativo decorrente do longo período de incubação da doença somado ao não diagnóstico precoce. A análise da distribuição dos agregados espaciais identificou 14 (7 de risco alto e 7 de risco baixo) e 6 (3 de risco alto e 3 de risco baixo) agrupamentos espaciais, considerando-se 10% e 50% da população em risco, respectivamente, em áreas com taxas de detecção alta e que possuem baixa qualidade de vida. O estimador Bayesiano empírico local possibilitou gerar índices corrigidos e com menores instabilidades. A análise de regressão múltipla espacial mostrou que as variáveis índice Gini, bioma predominante cerrado/caatinga e percentual de população urbana tiveram associação positiva e significativa para explicar o risco relativo (RR) no estado do Maranhão. Conclusões: O estudo mostrou que existem aglomerados com elevado risco para transmissão da hanseníase no estado do Maranhão. A associação entre o risco relativo da hanseníase e o percentual de população urbana indica que a hipótese que associa o M. leprae e a população que vive em condições de acentuada desigualdade socioeconômica ainda é forte. Essa hiperendemicidade pode demonstrar que o crescimento da população urbana é um preditor de incidência da hanseníase, face à urbanização descontrolada e ao fluxo de migrantes advindos de diferentes espaços rurais. Foi possível identificar áreas prioritárias para implementação de programas eficazes de controle de hanseníase no estado do Maranhão. / Leprosy, a chronic stigmatizing disease with the potential to cause neurological damage resulting from infection by Mycobacterium leprae. Current epidemiological studies have used clinical and spatial analysis for mapping of the main occurrence of disease outbreaks and high-risk areas. Analyze the municipalities of Maranhão state regarding the distribution of leprosy cases becomes another tool in the prevention and control of leprosy in the state by numerous factors like behaves as hyper-endemic area of leprosy; It presents intense migration to other interstate cities; and has great social contrasts marked by little or no basic infrastructure in some areas of several municipalities.. Objectives: To analyze the spatiotemporal distribution of leprosy in the Maranhão state, from 2001 to 2013. To identify the spatiotemporal clusters occurrence of probable high transmission (risk) and check for association of this distribution of relative risk (RR) detection rates of the disease with the variables of geographic context as socioeconomic and environmental. Methodology: Clinical and epidemiological data was obtained from the Ministry of Healths Disease Reporting System and demographic data, environmental and digital cartographic bases were obtained from the Brazilian Geography and Statistics Institute. An ecological approach to trends transmissibility of spatiotemporal patterns, using the methods: spatial scan to identification the clusters of risk, considering the Discrete Poisson probability distribution model; empirical Bayesian method was applied for local rate flattening, using data from municipalities having as building strategy the criterion of contiguity; ecological regression modeling with considering a Poisson distribution in the Bayesian context, taking into account the spatial dependence, in order to evaluate the relationship between the occurrence of the dependent variable with demographic, socioeconomic and environmental variables. Results: The mean detection rate was 6.73 cases per 10,000 inhabitants, with 53,826 reported cases. The study revealed that the distribution of male cases (57.75%) showed a predominance over female (42.25%), with predominance of the disease in the age group upper than 15 years (89.87%). The high occurrence in operational classification multibacillary (60.10%) is a strong indication due to the long incubation period of the disease added to no early diagnosis. The analysis of the distribution of spatial clusters identified 14 (7 high risk and 7 low risk) and 6 (3 high risk and 3 low risk) spatial clusters, considering 10% and 50% of the population at risk in areas with high detection rates and which have low quality of life. Local empirical Bayes estimator allowed to generate fixed and minor instabilities indexes. The best results of modeling to spatial multiple regression analysis for the relative risk (RR) presented for the variables Gini index, cerrado/caatinga biome and percentage of urban population. Conclusions: The study showed that there are clusters at high risk for transmission of leprosy in the Maranhao state. The association between the relative risk of leprosy and the percentage of urban population indicates that the hypothesis that associates M. leprae and the population living in severe socioeconomic inequality is still strong. This hyperendemicity can demonstrate that the growth of the urban population is a predictor incidence of leprosy due to uncontrolled urbanization and the influx of migrants coming from different rural areas.It was possible to identify priority areas for implementation of effective leprosy control programs in the Maranhão state.
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The Spatial and Molecular Epidemiology of Lyme Disease in Eastern OntarioSlatculescu, Andreea M. 11 August 2023 (has links)
Lyme disease is an emerging tick-borne illness in Canada, with human case numbers increasing 15- to 20-fold since Lyme disease became nationally notifiable in 2009 until the present. In Ontario, Canada's largest province by population, average Lyme disease incidence across the province is similar to that of national estimates. However, in eastern Ontario, which is near tick endemic regions in the northeastern Unites States, Lyme disease incidence is disproportionately higher compared to the rest of the province.
The objectives of this thesis are to identify environmental Lyme disease risk areas in Ontario, to explore spatiotemporal trends in Lyme disease emergence, and to identify neighbourhood-level socioecological risk factors for Lyme disease. In addition, this thesis also aims to assess the risk of other tick-borne illnesses that are transmitted by the blacklegged tick, Ixodes scapularis, which is also the main vector for Lyme disease in Canada.
Using maximum entropy species distribution modelling to correlate blacklegged tick occurrence data with environmental variables, predictive risk models for I. scapularis and the Lyme disease pathogen, Borrelia burgdorferi, were developed. The model prediction was used to classify low and high environment risk areas and, using a case-control epidemiological study, we assessed that residence in risk areas was a strong predictor of Lyme disease. However, this relationship was modulated by socioecological factors linked to higher overall rurality of the locality of home residence. Spatial cluster analyses further revealed that human Lyme disease cases clustered in regions with the high numbers of reported B. burgdorferi-infected ticks in the environment. Many individuals residing in large metropolitan regions, like the City of Ottawa, reported tick exposures outside their public health unit of residence; however, local clusters of Lyme disease were also detected in suburban regions near conservation areas, trails, and urban woodlands. The prevalence of other tick-borne pathogens was low, although several pathogens of public health significance including Borrelia miyamotoi and Anaplasma phagocytophilum were detected at multiple sites surveyed for ticks between 2017-2021.
Overall, this thesis identify patterns in Lyme disease emergence (and potentially other tick-borne illnesses), defines environmental risk areas for Lyme disease in Ontario, and highlights important socioecological risk factors for Lyme disease in eastern Ontario.
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Geospatial Approaches to Social Determinants of Cancer OutcomesDong, Weichuan 19 November 2021 (has links)
No description available.
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