26 results on '"Werneck, Guilherme Loureiro"'
Search Results
2. Impact of 4% Deltamethrin-Impregnated Dog Collars on the Incidence of Human Visceral Leishmaniasis: A Community Intervention Trial in Brazil.
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Werneck, Guilherme Loureiro, Figueiredo, Fabiano Borges, and Cruz, Maria do Socorro Pires e
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VISCERAL leishmaniasis ,DOG collars ,POISSON regression ,SAND flies ,LEISHMANIA infantum ,FENITROTHION - Abstract
Background: In Brazil, human visceral leishmaniasis (HVL) is caused by the protozoan parasite Leishmania infantum, primarily transmitted by the sand fly Lutzomyia longipalpis, with dogs acting as the main urban reservoir. This study aims to evaluate the effectiveness of 4% deltamethrin-impregnated dog collars (DMC) on HVL incidence. Methods: This is a community intervention study carried out from 2012 to 2015 in the municipalities of Araguaína, State of Tocantins, and Montes Claros, State of Minas Gerais, Brazil. Two areas in each were randomly allocated to either (1) culling seropositive dogs + residual insecticide spraying (control area—CA) or (2) culling seropositive dogs + residual insecticide spraying + DMC fitted to dogs every six months for two years (intervention area—IA). Cases of HVL (n = 1202) occurring from 2008 to 2020 were identified from the Brazilian Reportable Diseases Information System and georeferenced to the control and intervention areas. The HVL cases from 2008 to 2012 were considered as occurring in the "pre-intervention" period. Those cases from 2013 to 2016 and from 2017 to 2020 were regarded as occurring in the "intervention" and "post-intervention" periods, respectively. We used a mixed-effects Poisson regression model to estimate the effectiveness of the intervention, comparing the changes from the pre-intervention period to the intervention and post-intervention periods in the control and intervention areas. Results: In Araguaína, there was a statistically significant reduction in the incidence of HVL in both the control and intervention areas, comparing both the intervention and post-intervention periods with the pre-intervention period. The intervention with DMC was significantly associated with a reduction in HVL when comparing the intervention and pre-intervention periods, yielding an effectiveness estimate of the DMC of 27% (IC95% 1–46%, p = 0.045). No differences were observed when comparing the pre- and post-intervention periods (p = 0.827). In Montes Claros, cases reduced in both the control and intervention areas from the pre-intervention period to the intervention period (p = 0.913). In the post-intervention period, the incidence increased in the control area, while cases continued to decrease in the DMC area (p = 0.188). Conclusions: The use of DMC was associated with a reduction of 27% in the incidence of HVL during the period of DMC delivery, indicating that DMC is effective as an additional strategy for controlling visceral leishmaniasis in Brazil. However, no significant reduction associated with DMC was detected after the intervention period, suggesting that a control program based on the large-scale deployment of DMC might have to be maintained for more extended periods without interruption. [ABSTRACT FROM AUTHOR]
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- 2024
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3. Spatial distribution of Leishmania seropositive dogs in the Angelim neighborhood, Teresina, Piauí, Brazil: appraisal of three spatial clustering methods.
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da Silva, Lília Aparecida Marques, Braga, José Ueleres, da Silva, João Pereira, e Cruz, Maria do Socorro Pires, de Oliveira, André Luiz Sá, and Werneck, Guilherme Loureiro
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VISCERAL leishmaniasis ,SCAN statistic ,LEISHMANIA ,LEISHMANIASIS ,DOGS ,CROSS-sectional method - Abstract
The detection of spatial clusters has been suggested as a potential tool for guiding the delivery of interventions against visceral leishmaniasis; however, little attention has been given to the consistency of results by using different spatial clustering methods. The present study aimed to assess the performance of three different techniques for identifying patterns in the spatial distribution of canine leishmaniasis in the city of Teresina, Brazil. This cross-sectional study was based on a serological survey for canine leishmaniasis in which each dog domicile was georeferenced to the exact location of each animal in space. The spatial analysis was performed using three methods: the Cuzick-Edwards statistic, the Hierarchical Nearest Neighbour analysis, and the Kulldorff Scan statistic. All techniques were able to identify clusters of high prevalences of canine leishmaniasis, but results were not consistent among techniques. The feasibility of the identification and location of clusters of cases in a restricted number of villages in neighborhoods might contribute to the optimization of control measures against visceral leishmaniasis. However, given the relative inconsistency of the results provided by the different methods, protocols for assessing clusters of diseases should always include more than one method of evaluation. [ABSTRACT FROM AUTHOR]
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- 2021
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4. Does deforestation drive visceral leishmaniasis transmission? A causal analysis.
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Santos, Cleber Vinicius Brito dos, Sevá, Anaiá da Paixão, Werneck, Guilherme Loureiro, and Struchiner, Cláudio José
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DEFORESTATION ,GIBBS sampling ,VECTOR-borne diseases ,LEISHMANIASIS ,GLOBAL burden of disease ,VISCERAL leishmaniasis - Abstract
Vector-borne diseases (VBDs) are important contributors to the global disease burden and are a key factor in perpetuating economic inequality. Although environmental changes are often cited as drivers of VBDs, the link between deforestation and VBD occurrence remains unclear. Here, we examined this relationship in detail using the spread of visceral leishmaniasis (VL) in São Paulo state (Brazil) as the case study. We used a two-step approach to estimate the causal effects (overall, direct, and indirect) of deforestation on the occurrence of the VL vector, canine visceral leishmaniasis (CVL), and human visceral leishmaniasis (HVL). We first estimated the parameters via a double Metropolis–Hastings algorithm and then estimated the causal effects through a Gibbs sampler. We observed that the odds of vector, CVL, and HVL occurrence were 2.63-, 2.07-, and 3.18-fold higher, respectively, in deforested compared with forested municipalities. We also identified a significant influence of the presence of vector, CVL, and HVL in one municipality on disease occurrence in previously naive neighbouring municipalities. Lastly, we found that a hypothetical reduction in deforestation prevalence from 50 to 0% across the state would reduce vector, CVL, and HVL occurrence by 11%, 6.67%, and 29.87%, respectively. Our results suggest that implementing an eco-friendly development strategy that considers trade-offs between agriculture, urbanization, and conservation could be an effective mechanism of controlling VL. [ABSTRACT FROM AUTHOR]
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- 2021
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5. Impacto presupuestario de las pruebas diagnósticas para la leishmaniosis visceral en Brasil
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Assis, Tália Santana Machado de, Azeredo-da-Silva, André Luís Ferreira de, Oliveira, Diana, Cota, Gláucia, Werneck, Guilherme Loureiro, and Rabello, Ana
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Visceral Leishmaniasis ,Controle Orçamentário ,Leishmaniasis Visceral ,Diagnóstico ,Budgetary Control ,Diagnosis ,Leishmaniose Visceral ,Control Presupuestario - Abstract
The aim of the present study was to estimate the financial costs of the incorporation and/or replacement of diagnostic tests for human visceral leishmaniasis (VL) in Brazil. The analysis was conducted from the perspective of the Brazilian Unified National Health System (SUS) over a period of three years. Six diagnostic tests were evaluated: the indirect immunofluorescence antibody test (IFAT), the IT LEISH rapid test, the parasitological examination of bone marrow aspirate, the direct agglutination test (DAT-LPC) standardized in the Clinical Research Laboratory, René Rachou Institute of the Oswaldo Cruz Foundation, the Kalazar Detect rapid test, and polymerase chain reaction (PCR). The assumptions used were the number of suspected cases of VL reported to the Brazilian Ministry of Health in 2014 and the direct cost of diagnostic tests. The costs to diagnose suspected cases of VL over three years using the IFAT and the DAT-LPC were estimated at USD 280,979.91 and USD 121,371.48, respectively. The analysis indicated that compared with the use of the IFAT, the incorporation of the DAT-LPC into the SUS would result in savings of USD 159,608.43. With regard to the budgetary impact of rapid tests, the use of IT LEISH resulted in savings of USD 21.708,72 over three years. Compared with a parasitological examination, diagnosis using PCR resulted in savings of USD 3,125,068.92 over three years. In this study, the replacement of the IFAT with the DAT-LPC proved financially advantageous. In addition, the replacement of the Kalazar Detect rapid test with the IT LEISH in 2015 was economically valuable, and the replacement of parasitological examination with PCR was indicated. Resumo: O estudo teve como objetivo estimar os custos financeiros da incorporação e/ou substituição dos testes diagnósticos para a leishmaniose visceral (LV) humana no Brasil. A análise foi realizada na perspectiva do Sistema Único de Saúde (SUS) ao longo de três anos. Foram avaliados seis testes diagnósticos: reação de imunofluorescência indireta (RIFI), teste rápido IT LEISH, exame parasitológico de aspirado de medula óssea, teste de aglutinação direta DAT-LPC padronizado pelo Laboratório de Pesquisas Clínicas do Instituto René Rachou, Fundação Oswaldo Cruz, teste rápido Kalazar Detect e reação em cadeia da polimerase (PCR). Os parâmetros utilizados foram o número de casos suspeitos de LV notificados ao Ministério da Saúde em 2014 e o custo direto dos testes diagnósticos. Os custos do diagnóstico de casos suspeitos de LV ao longo de três anos usando o RIFI e DAT-LPC foram estimados em USD 280.979,91 e USD 121.371,48, respectivamente. De acordo com a análise, comparado ao uso do RIFI, a incorporação do DAT-LPC pelo SUS resultaria numa economia de USD 159.608,43. Com relação ao impacto dos testes rápidos, o uso do IT LEISH resultou em economia de USD 21.708,72 ao longo de três anos. Comparado ao exame parasitológico, o diagnóstico com PCR resultou em economia de USD 3.125.068,92 ao longo de três anos. Neste estudo, a substituição do RIFI pelo DAT-LPC mostrou ser financeiramente vantajosa. Além disso, a substituição do teste rápido Kalazar Detect com o IT LEISH em 2015 foi economicamente apropriada, e a substituição do exame parasitológico pela PCR está economicamente indicada. Resumen: El objetivo del estudio fue estimar los costes financieros de la incorporación y/o sustitución de las pruebas diagnósticas para la leishmaniasis visceral (LV) humana en Brasil. El análisis se realizó desde la perspectiva del Sistema Único de Salud (SUS) a lo largo de tres años. Se evaluaron seis pruebas diagnósticas: reacción de inmunofluorescencia indirecta (RIFI), test rápido IT LEISH, examen parasitológico de aspirado de medula ósea, test de aglutinación directa DAT-LPC, estandarizado por el Laboratorio de Investigación Clínica del Centro de Investigación René Rachou, Fundación Oswaldo Cruz, test rápido Kalazar Detect y la reacción en cadena de la polimerasa (PCR). Los parámetros utilizados fueron el número de casos sospechosos de LV notificados al Ministerio de Salud en 2014 y el coste directo de los test diagnósticos. Los costes del diagnóstico de casos sospechosos de LV a lo largo de tres años, usando el RIFI y DAT-LPC, se estimaron en USD 280.979,91 y USD 121.371,48, respectivamente. De acuerdo con el análisis, comparado con el uso del RIFI, la incorporación del DAT-LPC por el SUS resultaría en un ahorro de USD 159.608,43. En relación con el impacto de los test rápidos, el uso del IT LEISH aportaba un ahorro de USD 21.708,72 a lo largo de tres años. Comparado con el examen parasitológico, el diagnóstico con PCR suponía un ahorro de USD 3.125.068,92 a lo largo de tres años. De acuerdo con el estudio, la sustitución del RIFI con el DAT-LPC mostró ser financieramente ventajosa. Asimismo, la sustitución del test rápido Kalazar Detect con el IT LEISH en 2015 representó un ahorro económico, y los resultados favorecieron la sustitución del examen parasitológico con PCR.
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- 2017
6. Burden of leishmaniasis in Brazil and federated units, 1990-2016: Findings from Global Burden of Disease Study 2016.
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Bezerra, Juliana Maria Trindade, de Araújo, Valdelaine Etelvina Miranda, Barbosa, David Soeiro, Martins-Melo, Francisco Rogerlândio, Werneck, Guilherme Loureiro, and Carneiro, Mariângela
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DISEASE incidence ,VISCERAL leishmaniasis ,TREATMENT effectiveness ,PREVENTION ,THERAPEUTICS ,GLOBAL burden of disease - Abstract
Background: The study presents estimates for the burden of visceral leishmaniasis (VL) and cutaneous and mucocutaneous leishmaniasis (CML) in Brazil and its 27 federated units using data from the Global Burden of Disease Study (GBD) 2016. Methodology: We report the incidence, years of life lost (YLL), years lived with disability (YLD), and disability-adjusted life years (DALY) for leishmaniasis in Brazil from 1990 to 2016. The metrics are presented as age-standardized rates per 100,000 inhabitants with their respective uncertainty intervals (95%UI) and relative percentages of change. Principal findings: The age-standardized incidence rate of leishmaniasis decreased 48.5% from 1990 (71.0, 95%UI 24.3–150.7) to 2016 (36.5, 95%UI 24.7–50.9), whereas the age-standardized DALY increased 83.6% over the studied period from 12.2 (95%UI 7.9–18.8) to 22.4 (95%UI 13.3–36.2). The age-standardized incidence rate and YLL for VL increased by 52.9% and 108% from 1990 to 2016, respectively. Considering CML, the age-standardized incidence rate and YLD decreased by 51% and 31.8% respectively for the same period. For VL, similar profiles for male and female were observed, with YLL and DALY increasing over time; with males presenting slightly higher values. The highest YLL rates were among "under 1-year old" children, which increased 131.2% from 1990 to 2016. Regarding CML, the highest values of YLD and DALY were verified among males, and YLD values showed a similar profile, with rates increasing with age. The VL burden increased in some states in the Northeast and Southeast regions and decreased for CML in some Northern states. Conclusion: The increase of VL burden over the study period might be associated with the difficulties in controlling the disease spread. Information regarding the weight of VL and CML, including the death and disability tolls that they cause, highlights the impact of these neglected diseases on public health and the importance of effective prevention and treatment. [ABSTRACT FROM AUTHOR]
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- 2018
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7. The burden of Neglected Tropical Diseases in Brazil, 1990-2016: A subnational analysis from the Global Burden of Disease Study 2016.
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Martins-Melo, Francisco Rogerlândio, Carneiro, Mariângela, Jr.Ramos, Alberto Novaes, Heukelbach, Jorg, Ribeiro, Antonio Luiz Pinho, and Werneck, Guilherme Loureiro
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DISEASE risk factors ,LIFE expectancy ,SCHISTOSOMIASIS ,VISCERAL leishmaniasis - Abstract
Background: Neglected Tropical Diseases (NTDs) are important causes of morbidity, disability, and mortality among poor and vulnerable populations in several countries worldwide, including Brazil. We present the burden of NTDs in Brazil from 1990 to 2016 based on findings from the Global Burden of Diseases, Injuries, and Risk Factors Study 2016 (GBD 2016). Methodology: We extracted data from GBD 2016 to assess years of life lost (YLLs), years lived with disability (YLDs), and disability-adjusted life-years (DALYs) for NTDs by sex, age group, causes, and Brazilian states, from 1990 to 2016. We included all NTDs that were part of the priority list of the World Health Organization (WHO) in 2016 and that are endemic/autochthonous in Brazil. YLDs were calculated by multiplying the prevalence of sequelae multiplied by its disability weight. YLLs were estimated by multiplying each death by the reference life expectancy at each age. DALYs were computed as the sum of YLDs and YLLs. Principal findings: In 2016, there were 475,410 DALYs (95% uncertainty interval [UI]: 337,334–679,482; age-standardized rate of 232.0 DALYs/100,000 population) from the 12 selected NTDs, accounting for 0.8% of national all-cause DALYs. Chagas disease was the leading cause of DALYs among all NTDs, followed by schistosomiasis and dengue. The sex-age-specific NTD burden was higher among males and in the youngest and eldest (children <1 year and those aged ≥70 years). The highest age-standardized DALY rates due to all NTDs combined at the state level were observed in Goiás (614.4 DALYs/100,000), Minas Gerais (433.7 DALYs/100,000), and Distrito Federal (430.0 DALYs/100,000). Between 1990 and 2016, the national age-standardized DALY rates from all NTDs decreased by 45.7%, with different patterns among NTD causes and Brazilian states. Most NTDs decreased in the period, with more pronounced reduction in DALY rates for onchocerciasis, lymphatic filariasis, and rabies. By contrast, age-standardized DALY rates due to dengue, visceral leishmaniasis, and trichuriasis increased substantially. Age-standardized DALY rates decreased for most Brazilian states, increasing only in the states of Amapá, Ceará, Rio Grande do Norte, and Sergipe. Conclusions/Significance: GBD 2016 findings show that, despite the reduction in disease burden, NTDs are still important and preventable causes of disability and premature death in Brazil. The data call for renewed and comprehensive efforts to control and prevent the NTD burden in Brazil through evidence-informed and efficient and affordable interventions. Multi-sectoral and integrated control and surveillance measures should be prioritized, considering the population groups and geographic areas with the greatest morbidity, disability, and most premature deaths due to NTDs in the country. [ABSTRACT FROM AUTHOR]
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- 2018
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8. Budgetary impact of diagnostic tests for visceral leishmaniasis in Brazil.
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de Assis, Tália Santana Machado, de Azeredo-da-Silva, André Luís Ferreira, Oliveira, Diana, Cota, Gláucia, Werneck, Guilherme Loureiro, and Rabello, Ana
- Abstract
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- 2017
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9. Panorama dos estudos sobre nutrição e doenças negligenciadas no Brasil
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Werneck, Guilherme Loureiro, Hasselmann, Maria Helena, and Gouvêa, Thaise Gasser
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Visceral leishmaniasis ,Leishmaniose visceral ,Esquistossomose ,Malnutrition ,Schistosomiasis ,Nutrição ,Malária ,Desnutrição ,Chagas' Disease ,Doença de Chagas ,Nutrition ,Malaria - Abstract
O objetivo deste artigo é revisar a literatura acerca da relação entre nutrição e doenças infecciosas negligenciadas em populações brasileiras, focalizando especificamente a doença de Chagas, a malária, a esquistossomose e a leishmaniose visceral. A revisão da literatura foi realizada em janeiro de 2010 a partir de um levantamento bibliográfico nas bases SciELO, LILACS e Medline. Foram captados 293 resumos; dentre estes, 66 foram selecionados para leitura de texto completo e 43 incluídos na revisão. A presente revisão salienta a relevância dos estudos nutricionais no campo da Saúde Coletiva para melhor compreensão dos aspectos envolvidos no risco e prognóstico de malária, esquistossomose, leishmaniose visceral e doença de Chagas. Evidencia-se também certo desbalanceamento na literatura sobre o tema, com muito mais estudos experimentais do que estudos em populações humanas. Ainda que os primeiros sejam essenciais para esclarecer os mecanismos fisiopatológicos subjacentes à relação entre déficits nutricionais e estas doenças, estudos bem delineados em populações humanas são fundamentais para que o conhecimento científico se traduza em ações efetivas para o controle de doenças negligenciadas. The objective of this paper is to review the literature on the relationship between nutrition and neglected infectious disease in Brazilian populations, in particular Chagas' Disease, malaria, schistosomiasis and visceral leishmaniasis. The literature review was performed in January 2010 by searching the databases SciELO, LILACS and Medline. Two-hundred and ninety-three abstracts were retrieved, 66 of them were selected for full-text analysis and 43 were included in the review. This review reinforces the relevance of nutritional studies in public health for better understanding the aspects involved in the risk and prognosis of malaria, schistosomiasis, visceral leishmaniasis and Chagas' Disease. It was possible to detect an unbalance in the literature about the theme, with much more experimental studies than population-based studies. Although the first are essential for helping to understand the pathophysiological mechanisms underlying the association between nutritional deficits and those diseases, well designed population-based studies are fundamental for the translation of scientific research into effective actions for controlling neglected diseases.
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- 2011
10. Is severe visceral leishmaniasis a systemic inflammatory response syndrome? A case control study
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Costa,Carlos Henrique Nery, Werneck,Guilherme Loureiro, Costa,Dorcas Lamounier, Holanda,Thiago Ayres, Aguiar,Guilherme Brasileiro, Carvalho,Aline Santos, Cavalcanti,Janaína Costa, and Santos,Loryenne Santos
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Visceral leishmaniasis ,AIDS ,Kala-azar ,Severe inflammatory response syndrome ,Bleeding - Abstract
INTRODUCTION: The objective of the study is to identify the main risk factors for death by New World visceral leishmaniasis and establish a coherent pathogenic substrate of severe disease based on clinical findings. METHODS: Seventy-six deceased inpatients and 320 successfully treated inpatients with VL were studied in a case control study. RESULTS: Bacterial infection and bleeding were mutually exclusive events leading to death. Five risk factors were unique for death by bacterial infection (malnutrition, pulmonary rales, severe anemia, severe absolute neutropenia and higher neutrophil count), while another six were unique for death by bleeding (jaundice, severe relative neutropenia, severe thrombocytopenia, liver injury, kidney failure, higher bone marrow parasite load). Bacterial infection, bleeding, severe anemia, diarrhea, dyspnea, edema, jaundice and bone marrow parasite load were the main syndromes of visceral leishmaniasis among successfully treated patients. CONCLUSIONS: The data support the idea that bacterial infections are due to immune paralysis. Broad organ and system involvement is plausibly due to the high production of proinflammatory cytokines, whose actions fit well with visceral leishmaniasis. The syndromes and causative mediators are typical of a slowly developing systemic inflammatory response syndrome.
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- 2010
11. Is severe visceral leishmaniasis a systemic inflammatory response syndrome? A case control study
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Costa, Carlos Henrique Nery, Werneck, Guilherme Loureiro, Costa, Dorcas Lamounier, Holanda, Thiago Ayres, Aguiar, Guilherme Brasileiro, Carvalho, Aline Santos, Cavalcanti, Janaína Costa, and Santos, Loryenne Santos
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Visceral leishmaniasis ,AIDS ,Kala-azar ,Severe inflammatory response syndrome ,Síndrome da resposta inflamatória sistêmica ,Leishmaniose visceral ,Bleeding ,Calazar ,Sangramento - Abstract
INTRODUCTION: The objective of the study is to identify the main risk factors for death by New World visceral leishmaniasis and establish a coherent pathogenic substrate of severe disease based on clinical findings. METHODS: Seventy-six deceased inpatients and 320 successfully treated inpatients with VL were studied in a case control study. RESULTS: Bacterial infection and bleeding were mutually exclusive events leading to death. Five risk factors were unique for death by bacterial infection (malnutrition, pulmonary rales, severe anemia, severe absolute neutropenia and higher neutrophil count), while another six were unique for death by bleeding (jaundice, severe relative neutropenia, severe thrombocytopenia, liver injury, kidney failure, higher bone marrow parasite load). Bacterial infection, bleeding, severe anemia, diarrhea, dyspnea, edema, jaundice and bone marrow parasite load were the main syndromes of visceral leishmaniasis among successfully treated patients. CONCLUSIONS: The data support the idea that bacterial infections are due to immune paralysis. Broad organ and system involvement is plausibly due to the high production of proinflammatory cytokines, whose actions fit well with visceral leishmaniasis. The syndromes and causative mediators are typical of a slowly developing systemic inflammatory response syndrome. INTRODUÇÃO: O objetivo do estudo foi i dentificar os principais fatores de risco para morte na leishmaniose visceral do Novo Mundo e estabelecer um substrato patogênico baseado nos achados clínicos coerente para doença grave. MÉTODOS: Em um estudo caso-controle, foram estudados 76 pacientes internados que faleceram e 320 pacientes internados tratados com sucesso. RESULTADOS: Infecção bacteriana e sangramento foram eventos que levaram à morte, mutuamente exclusivos. Cinco fatores de risco foram únicos para morte por infecção bacteriana (desnutrição, estertores pulmonares, anemia grave, neutropenia absoluta grave e número de leucócitos aumentados), enquanto outros seis foram exclusivos para morte por sangramento (icterícia, neutropenia relativa grave, trombocitopenia grave, lesão hepática, insuficiência renal, maior carga de parasitas na medula óssea). Entre os pacientes tratados com sucesso, as principais síndromes de leishmaniose visceral foram infecções bacterianas, sangramento, anemia grave, diarreia, dispneia, edema, icterícia e carga de parasitas na medula óssea. CONCLUSÕES: Os dados apoiam a ideia de que as infecções bacterianas são secundárias a imunoparalisia. O amplo envolvimento de órgãos e sistemas é de forma plausível devido a elevada produção de citocinas pró-inflamatórias, cujas ações se encaixam com a leishmaniose visceral. As síndromes e os mediadores causais são típicos da síndrome de resposta inflamatória sistêmica, desenrolando-se lentamente.
- Published
- 2010
12. Fatores associados à incidência da leishmaniose visceral em área urbana: um estudo ecológico em Teresina, Piauí, Brasil
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Cerbino Neto,José, Werneck,Guilherme Loureiro, and Costa,Carlos Henrique Nery
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Visceral Leishmaniasis ,Spatial Analysis ,Geographic Information Systems ,Análise Espacial ,Leishmaniose Visceral ,Sistemas de Informação Geográfica - Abstract
The objective of this study was to identify socioeconomic and environmental factors associated with the incidence of visceral leishmaniasis in the city of Teresina, Piauí State, Brazil. This was an ecological study based on 1,744 cases reported from 1991 to 2000, and the city's neighborhoods served as the unit of analysis. Mean annual incidence rates were related to socioeconomic and demographic indicators and a vegetation index derived from remote sensing images by means of spatial multiple linear regression models. The neighborhoods with the highest incidence rates were mostly located in the city's peripheral areas. Multivariate analysis identified an interaction between population growth and the vegetation index, so that areas with high population growth and abundant vegetation showed the highest incidence rates. The percentage of households with piped water was inversely associated with visceral leishmaniasis incidence. Spatial distribution of visceral leishmaniasis in Teresina during the 1990s was heterogeneous, and incidence of the disease was associated with the peripheral neighborhoods with the heaviest vegetation cover, subject to rapid occupation and lack of adequate sanitation infrastructure. O objetivo deste estudo é identificar fatores sócio-ambientais associados à incidência de leishmaniose visceral na área urbana de Teresina, Piauí, Brasil. Este estudo ecológico é baseado em 1.744 casos ocorridos entre 1991 e 2000 e tem como unidade de análise os bairros da cidade. As taxas de incidências anuais médias foram relacionadas a indicadores sócio-econômicos e demográficos e a um índice de vegetação derivado de imagem de sensoriamento remoto por meio de modelos de regressão linear múltipla espacial. Os bairros que apresentaram maiores incidências estavam majoritariamente localizados nas regiões periféricas da cidade. Na análise multivariada identificou-se uma interação entre crescimento populacional e índice de vegetação, de forma que áreas com alto crescimento populacional e com vegetação abundante apresentaram as maiores taxas de incidência da doença. O percentual de domicílios com água canalizada esteve inversamente associado à incidência da leishmaniose visceral. A distribuição espacial da leishmaniose visceral na área urbana de Teresina durante a década de 1990 foi heterogênea, estando sua incidência associada aos bairros periféricos com maior cobertura vegetal, submetidos à ocupação rápida e sem infra-estrutura sanitária adequada.
- Published
- 2009
13. A remote sensing application to investigate urban endemics
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Correia,Virginia Ragoni de Moraes, Monteiro,Antônio Miguel Vieira, Carvalho,Marilia Sá, and Werneck,Guilherme Loureiro
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Visceral Leishmaniasis ,Remote Sensors ,Endemic Diseases ,Sensores Remotos ,Doenças Endêmicas ,Leishmaniose Visceral - Abstract
Este artigo apresenta um estudo de caso - aspectos ambientais relacionados à ocorrência da leishmaniose visceral em Teresina, Piauí, Brasil, no período de 1993 a 1996 - visando a discutir o uso de um conjunto de métodos aplicados a imagens de sensoriamento remoto em média resolução no estudo de endemias transmitidas por vetores em áreas urbanas. Foram apresentadas as técnicas essenciais a esse tipo de procedimentos: registro, correção geométrica, restauração, fusão, segmentação e classificação. Quatro classificadores, Maxver, Bhattacharya, K-médias e Isoseg, foram comparados utilizando o índice de correlação intraclasse aplicado à proporção de área segundo cada classe nos setores censitários. Os métodos de avaliação utilizados não tiveram o propósito de definir o melhor classificador, mas desenhar cenários de classificação, de forma a reconhecer as classes melhor identificáveis em área urbana. Mesmo dispondo-se de recursos limi-tados, imagens de baixo custo, ampla disponibilidade e média resolução, sistemas livres para processamento e integração das informações, é possível identificar as características de ocupação do solo de interesse potencial na análise de riscos ambientais para a ocorrência de endemias urbanas transmitidas por vetores. This paper presents a case study on environmental aspects related to the occurrence of visceral leishmaniasis in Teresina, Piauí, Brazil, from 1993 to 1996, in order to discuss the use of some appropriate geo-processing methods for median-resolution remote sensing images potentially useful for studying vector-borne transmissible diseases in urban areas. We present the main techniques: registration, geometric correction, restoration, fusion, segmentation, and classification. Using intra-class correlation indices applied to the proportion of area by class in the census tract, we compare four classifiers: Maxver, Bhattacharya, K-means, and Isoseg. This comparison was not devised to choose the best classifier, but to depict different classification scenarios aimed at recognizing the best identifiable image classes in urban settings. We conclude that even with limited resources, using low-cost and easily available median resolution images and free software to process and integrate information, it is possible to identify land use characteristics, potentially appropriate for analyzing urban areas exposed to environmental risk for vector-borne diseases.
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- 2007
14. Visceral leishmaniasis and HIV/AIDS in Brazil: Are we aware enough?
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Leite de Sousa-Gomes, Marcia, Werneck, Guilherme Loureiro, and Romero, Gustavo Adolfo Sierra
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VISCERAL leishmaniasis , *HIV-positive persons , *EPIDEMIOLOGICAL models , *METROPOLITAN areas , *URBANIZATION , *PATIENTS - Abstract
Background: The urbanization of visceral leishmaniasis (VL) and the concurrent movement of the HIV infection to rural areas in Brazil are possible mechanisms associated with an increased number of Leishmania/HIV coinfected people. This study aimed to describe the clinical and epidemiological profile of VL/HIV coinfected patients and compare this profile to non-coinfected VL patients. Methods: Cases of VL/HIV coinfection were obtained through a probabilistic record linkage of databases of VL and AIDS cases from the Brazilian Ministry of Health. Results: We retrieved 760 cases of VL/HIV coinfection, most prevalent in adult males, with incidence ranging from 0.01 to 0.07 cases, per 100.000 population, in 2001 and 2010, respectively. Case-fatality rates were 27.3% in 2001 and 23.2% in 2010. Weakness, weight loss, cough, other associated infections and haemorrhagic phenomena were more commonly found among coinfected patients, which had a fatality rate three times higher as compared to the non-coinfected group. The relapse proportion was two times greater among coinfected (6.3%) than non-coinfected (3.1%). Conclusions: The results found herein contribute to the increase of knowledge of the epidemiological situation of VL/HIV coinfection in Brazil and reinforce the necessity of implementing specific strategies to improve early case detection and efficacious and less toxic treatment in order to achieve lower case-fatality rates. [ABSTRACT FROM AUTHOR]
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- 2017
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15. Risk Factors for Adverse Prognosis and Death in American Visceral Leishmaniasis: A Meta-analysis.
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Belo, Vinícius Silva, Struchiner, Claudio José, Barbosa, David Soeiro, Nascimento, Bruno Warlley Leandro, Horta, Marco Aurélio Pereira, da Silva, Eduardo Sérgio, and Werneck, Guilherme Loureiro
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VISCERAL leishmaniasis ,PROGNOSIS ,PROGNOSTIC models ,BACTERIAL diseases ,SYMPTOMS ,FEBRILE neutropenia ,JAUNDICE - Abstract
Background: In the current context of high fatality rates associated with American visceral leishmaniasis (VL), the appropriate use of prognostic factors to identify patients at higher risk of unfavorable outcomes represents a potential tool for clinical practice. This systematic review brings together information reported in studies conducted in Latin America, on the potential predictors of adverse prognosis (continued evolution of the initial clinical conditions of the patient despite the implementation of treatment, independent of the occurrence of death) and death from VL. The limitations of the existing knowledge, the advances achieved and the approaches to be used in future research are presented. Methods/Principal Findings: The full texts of 14 studies conforming to the inclusion criteria were analyzed and their methodological quality examined by means of a tool developed in the light of current research tools. Information regarding prognostic variables was synthesized using meta-analysis. Variables were grouped according to the strength of evidence considering summary measures, patterns and heterogeneity of effect-sizes, and the results of multivariate analyses. The strongest predictors identified in this review were jaundice, thrombocytopenia, hemorrhage, HIV coinfection, diarrhea, age <5 and age >40–50 years, severe neutropenia, dyspnoea and bacterial infections. Edema and low hemoglobin concentration were also associated with unfavorable outcomes. The main limitation identified was the absence of validation procedures for the few prognostic models developed so far. Conclusions/Significance: Integration of the results from different investigations conducted over the last 10 years enabled the identification of consistent prognostic variables that could be useful in recognizing and handling VL patients at higher risk of unfavorable outcomes. The development of externally validated prognostic models must be prioritized in future investigations. Author Summary: In contrast to other clinical presentations of leishmaniasis in Latin America, American visceral leishmaniasis (VL) can lead to death in 5-10% of patients under treatment. The fatality rates associated with this disease have remained stable at a high level over the years in Brazil and are neither recorded in under-treatment patients from endemic countries of the Old World nor from non-endemic countries where such cases are imported. Since VL-induced lethality can occur even after the implementation of recommended therapy, the understanding of individual, clinical and laboratory factors that predispose to an unfavorable outcome might represent an important feature for informing better practice in the clinical management of cases. The present systematic review with meta-analysis brings together information on various prognostic variables associated with the severity of VL. Potential predictors identified in the studies surveyed were grouped according to the strength of evidence available, and 13 were considered to be of significant relevance. The gaps in the existing knowledge and the need for the development of externally validated prognostic models were also discussed. The results presented herein could be useful in identifying patients at higher risk of unfavorable evolution or death from VL, and might provide an aid in decision-making regarding the clinical management of VL cases. [ABSTRACT FROM AUTHOR]
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- 2014
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16. Lipoprotein Lipase and PPAR Alpha Gene Polymorphisms, Increased Very-Low-Density Lipoprotein Levels, and Decreased High-Density Lipoprotein Levels as Risk Markers for the Development of Visceral Leishmaniasis by Leishmania infantum.
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Teixeira Carvalho, Márcia Dias, Alonso, Diego Peres, Vieira Vendrame, Célia Maria, Costa, Dorcas Lamounier, Nery Costa, Carlos Henrique, Werneck, Guilherme Loureiro, Martins Ribolla, Paulo Eduardo, and Goto, Hiro
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LIPOPROTEIN lipase ,GENETIC polymorphisms ,LOW density lipoproteins ,HIGH density lipoproteins ,BIOMARKERS ,VISCERAL leishmaniasis ,LEISHMANIA infantum - Abstract
In visceral leishmaniasis (VL) endemic areas, a minority of infected individuals progress to disease since most of them develop protective immunity.Therefore, we investigated the riskmarkers of VL within nonimmune sector. Analyzing infected symptomatic and, asymptomatic, and noninfected individuals, VL patients presented with reduced high-density lipoprotein cholesterol (HDLC), elevated triacylglycerol (TAG), and elevated very-low-density lipoprotein cholesterol (VLDL-C) levels. A polymorphism analysis of the lipoprotein lipase (LPL) gene using HindIII restriction digestion (N = 156 samples) (H+ = the presence and H- = the absence of mutation) revealed an increased adjusted odds ratio (OR) of VL versus noninfected individuals when the H+/H+ was compared with the H-/H- genotype (OR = 21.3; 95% CI = 2.32-3335.3; P = 0.003).The H+/H+ genotype and the H+ allele were associated with elevated VLDL-C and TAG levels (P < 0.05) and reduced HDL-C levels (P < 0.05). An analysis of the L162V polymorphism in the peroxisome proliferator-activated receptor alpha (PPARα) gene (n = 248) revealed an increased adjusted OR when the Leu/Val was compared with the Leu/Leu genotype (OR = 8.77; 95% CI = 1.41-78.70; P = 0.014). High TAG (P = 0.021) and VLDL-C (P = 0.023) levels were associated with susceptibility to VL, whereas low HDL (P = 0.006) levels with resistance to infection.The mutated LPL and the PPARα Leu/Val genotypes may be considered risk markers for the development of VL. [ABSTRACT FROM AUTHOR]
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- 2014
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17. Factors Associated with Visceral Leishmaniasis in the Americas: A Systematic Review and Meta-Analysis.
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Belo, Vinícius Silva, Werneck, Guilherme Loureiro, Barbosa, David Soeiro, Simões, Taynãna César, Nascimento, Bruno Warlley Leandro, da Silva, Eduardo Sérgio, and Struchiner, Claudio José
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VISCERAL leishmaniasis , *SAND flies , *LEISHMANIA infantum , *DOGS , *CHICKEN coops , *Q fever - Abstract
Background: Still today, more than 30 years after the beginning of the process of visceral leishmaniasis' urbanization, there is little knowledge about the risk factors for its occurrence, despite their relevance to the control and understanding of disease dynamics. The present study is the first systematic review with meta-analysis about factors associated with Leishmania infantum infection in humans in the Americas. Methods and Findings: After searching different databases, consultations to the reference lists of articles and to experts in the field, 51 studies were reviewed. Theoretical discussions or meta-analysis of p-values or of effect sizes were used to pool information about each variable. The Q test and the I2 statistic were used to assess heterogeneities among the studies. Male sex was associated with visceral leishmaniasis in studies which used the leishmanin skin test for diagnosis and in those where the outcome was the clinical disease; the opposite occurred when serological diagnosis was applied. Younger individuals were less frequently infected than adults, but were more prone to illness. Although with different levels of evidence and of heterogeneity, the presence of dogs at home, higher dog seropositivity in nearby areas, lower socioeconomic status and highly vegetated areas were associated with L. infantum infection. This was not noticed for the presence of chickens in the house and with nutritional status. Susceptibilities to bias and limitations in the analysis and in the description of results were often identified in the studies analyzed. Conclusions: Results showed the existence of consistent patterns for some of the factors analyzed and should be taken into account in developing more effective and well-targeted control measures. Studies must be conducted in new areas of the continent, with improved methodological quality and prioritizing the investigation of the patterns identified and their causes, as well as variables for which knowledge is poor. Author Summary: Visceral leishmaniasis (VL) is the most severe clinical form of leishmaniasis. In the Americas, VL is a zoonosis caused by the protozoan parasite Leishmania infantum, an intracellular micro-organism transmitted to humans through the bite of female phlebotomine sand flies. The domestic dog is considered the main reservoir and human beings are dead-end hosts. The disease occurs in 12 countries of the New World and Brazil accounts for 90% of the reported cases. The factors associated with infection are only partially understood, making harder understanding the disease dynamics and the development of effective and well-targeted control measures. Our work is the first systematic review with meta-analysis about factors associated with human visceral leishmaniasis in the Americas. It provides an organization of the available information, the description of more accurate data on the role of each of the factors studied, the evaluation of possible causes of heterogeneity in the results of the studies as well as the analysis of the quality of publications and limitations in the existing knowledge. The results of this study might be useful in the definition of which and where target interventions should be delivered, and for guiding researchers towards the development of future studies of better methodological quality. [ABSTRACT FROM AUTHOR]
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- 2013
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18. Latent class analysis of diagnostic tests for visceral leishmaniasis in Brazil.
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Machado de Assis, Tália Santana, Rabello, Ana, and Werneck, Guilherme Loureiro
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VISCERAL leishmaniasis ,LATENT class analysis (Statistics) ,LONGITUDINAL method ,MICROSCOPICAL technique ,ENZYME-linked immunosorbent assay ,AGGLUTINATION tests ,ANTIGENS ,DIAGNOSIS - Abstract
Copyright of Tropical Medicine & International Health is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
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- 2012
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19. Factors associated with the incidence of urban visceral leishmaniasis: an ecological study in Teresina, Piauí State, Brazil.
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Neto, José Cerbino, Werneck, Guilherme Loureiro, and Costa, Carlos Henrique Nery
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Copyright of Cadernos de Saude Publica is the property of Escola Nacional de Saude Publica Sergio Arouca and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
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- 2009
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20. Uma aplicação do sensoriamento remoto para a investigação de endemias urbanas.
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de Moraes Correia, Virginia Ragoni, Monteiro, Antônio Miguel Vieira, Carvalho, Marilia Sá, and Werneck, Guilherme Loureiro
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Copyright of Cadernos de Saude Publica is the property of Escola Nacional de Saude Publica Sergio Arouca and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
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- 2007
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21. Spatial distribution of visceral leishmaniasis-HIV coinfection in Teresina/PI, 2006 to 2015
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Silva, Luciana da Rocha Mota da, Werneck, Guilherme Loureiro, Braga, Jose Ueleres, Medronho, Roberto de Andrade, and Almeida, Andréa Sobral de
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Visceral leishmaniasis ,Coinfection ,Leishmaniose visceral ,Geographic Information System ,CIENCIAS DA SAUDE::SAUDE COLETIVA [CNPQ] ,HIV ,Sistema de Informação Geográfica ,Coinfecção - Abstract
Submitted by Boris Flegr (boris@uerj.br) on 2020-07-05T16:00:04Z No. of bitstreams: 1 Dissertacao Luciana Mota da Silva.pdf: 1396939 bytes, checksum: 02798fe2a7f9c8a4da36378d4c949367 (MD5) Made available in DSpace on 2020-07-05T16:00:04Z (GMT). No. of bitstreams: 1 Dissertacao Luciana Mota da Silva.pdf: 1396939 bytes, checksum: 02798fe2a7f9c8a4da36378d4c949367 (MD5) Previous issue date: 2018-06-28 Each year occur approximately 50 to 90 thousand new cases of visceral leishmaniasis (VL). More than 90% of the cases of VL occur in seven countries of the world: Brazil, Ethiopia, India, Kenya, Somalia, Sudan and South Sudan. In Latin America, 96% occur in Brazil. The VL-HIV coinfection has been considered as emerging disease in several regions of the world depending on the geographical overlap of both infections as a result of leishmaniasis urbanization and HIV infection interiorization. The VL-HIV coinfection usually results in unfavorable treatment responses, frequent relapses and premature deaths. The objective of this study was to describe and analyze the clinical and epidemiologic profiles and the spatial and temporal distribution of VL-HIV coinfection in Teresina/PI, from 2006 to 2015. It is a cross-sectional study, with temporal dimension, developed from geo-referenced data for the address of residence domicile concerning notified and confirmed VL and VL-HIV cases in the Brazilian Disease Information System. From the total number of cases of LV notified within the period of the study (737), 19.4% were of VL-HIV coinfection. The proportion of VL-HIV cases coinfection in relation to LV cases was 8.6% in 2006 and 47.7% in 2015, the coefficient of incidence was 0.87 cases per 100,000 inhabitants and 2.49 cases per 100.00 inhabitants, in the same periods. Highlights the clinical and laboratory diagnosis difference between the two groups with weakness, weight loss, infection and hemorrhagic phenomena the most frequent clinical manifestations in patients with LV-HIV. The mortality and recurrence were approximately two times higher in this group, 11.4% and 13.3%, respectively. It was evidenced greater VL-HIV spatial aggregation cases in relation to that observed for LV cases. The results presented in this research contributes to the knowledge about the clinical and epidemiological diagnosis and the process of VL-HIV coinfection occurrence, potentiating prevention and health planning actions. A cada ano ocorrem aproximadamente 50 a 90 mil novos casos de leishmaniose visceral (LV). Mais de 90% dos casos de LV ocorrem em sete países no mundo: Brasil, Etiópia, Índia, Quênia, Somália, Sudão do Sul e Sudão. Na América Latina, 96% ocorrem no Brasil. A coinfecção LV-HIV tem sido considerada como doença emergente em várias regiões do mundo em função da superposição geográfica das duas infecções como consequência da urbanização das leishmanioses e da interiorização da infecção por HIV. A coinfecção LV-HIV geralmente resulta em respostas desfavoráveis ao tratamento, frequentes recidivas e óbitos prematuros. Este estudo teve como objetivo descrever e analisar o perfil clínicoepidemiológico e a distribuição espacial e temporal da coinfecção da LV-HIV em Teresina/PI, de 2006 a 2015. Trata-se de um estudo seccional, com dimensão temporal, desenvolvido a partir de dados espaciais georreferenciados para o endereço do domicílio de residência referentes aos casos de LV e LV-HIV notificados e confirmados no Sistema de Informação de Agravos de Notificação (SINAN). Do total de casos de LV notificados no período do estudo (737), 19,4% eram de coinfecção LV-HIV. A proporção de casos da coinfecção LV-HIV em relação aos casos de LV foi de 8,6%, em 2006 e 47,7% em 2015, o coeficiente de incidência foi de 0,87 casos por 100.000 habitantes e 2,49 casos por 100.00 habitantes, para os mesmos períodos. Destaca-se a diferença entre o diagnóstico clínico e laboratorial entre os dois grupos sendo fraqueza, emagrecimento, quadro infeccioso e fenômenos hemorrágicos as manifestações clínicas mais frequentes nos casos com LV-HIV. A letalidade e a recidiva foram, aproximadamente, duas vezes maiores nesse grupo, 11,4% e 13,3%, respectivamente. Foi evidenciada maior agregação espacial dos casos LV-HIV em relação àquela observada para os casos de LV. Os resultados apresentados neste estudo contribuem para o conhecimento sobre o diagnóstico clínicoepidemiológico e o processo de ocorrência da coinfecção LV-HIV, potencializando ações de prevenção e planejamento em saúde.
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- 2018
22. Environmental characteristics and the occurrence of visceral leishmaniasis in Teresina, Piauí: an application using remote sensing
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Gouveia, Cheryl, Werneck, Guilherme Loureiro, Almeida, Andréa Sobral de, Serpa Filho, Arlindo, Braga, Jose Ueleres, Santos, Reinaldo Souza dos, and Figueiredo, Fabiano Borges
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Visceral leishmaniasis ,Fatores de risco ,Epidemiology ,Leishmaniose visceral ,Spatial analysis ,Remote sensing ,Leishmaniose canina ,CIENCIAS DA SAUDE::SAUDE COLETIVA::EPIDEMIOLOGIA [CNPQ] ,Análise espacial ,Risk factors ,Vigilância em saúde ,Sensoriamento remoto ,Canine leishmaniasis ,Epidemiologia ,Health surveillance - Abstract
Submitted by Boris Flegr (boris@uerj.br) on 2020-08-02T16:52:50Z No. of bitstreams: 1 Tese_Cheryl Gouveia.pdf: 2802166 bytes, checksum: dfdb26edc5985220039cfff51b82a1af (MD5) Made available in DSpace on 2020-08-02T16:52:50Z (GMT). No. of bitstreams: 1 Tese_Cheryl Gouveia.pdf: 2802166 bytes, checksum: dfdb26edc5985220039cfff51b82a1af (MD5) Previous issue date: 2013-07-15 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior In the Americas, visceral leishmaniasis (VL) undergoes an active process of urbanization and the domestic dog is considered to be the main reservoir of the disease in this scenario, although its role in the transmission cycle is not fully explained. This study aimed to investigate, by spatial data analysis and remote sensing images, the association between environmental factors with the occurrence of canine infection by Leishmania chagasi and their spatial correlation with the human disease in the city of Teresina (Piauí-Brazil), where first urban epidemic of LV in Brazil was reported. The results are presented in the form of two manuscripts, which used georeferenced data obtained through a serological canine survey carried out during 2011 canine, in localities with moderate or severe transmission. In the first manuscript, the multilevel logistic regression approach was used to correlate the prevalence of canine infection with the environmental variables of grids with 900m2 (30mx30m) where the residence was located, adjusting to the dogs' individual characteristics (gender, age and race) and characteristics of the residences. The environmental analysis was performed with 717 dogs distributed in 494 households and 396 grids. The percentage of the area of grid covered by clear pavement (bare soil or old asphalted streets) >16.5% was the only environmental variable associated with canine infection by L. chagasi (Odds ratio [OR] = 2.00, 95% confidence interval [95% CI]: 1.22 - 3.26). These probably correspond to impoverished areas with inadequate infrastructure suggesting the occurrence of an urban cycle similar to those observed in rural and periurban areas. In the second manuscript, by the hierarchical analysis of nearest neighbor, were checked seven clusters of highest concentration of seropositve dogs in relation to seronegative in less urbanized areas with sparse vegetation. This analysis was performed with 322 dogs distributed in five boroughs. The spatial relationship between seropositive dogs and human cases was investigated by the method of average distance between points and was analyzed by t-test. The human cases were closer to the seropositive dogs when compared to the distance from the seronegative ones, suggesting the existence of a spatial relationship between the human LV and canine infection. The results contribute to a greater understanding of the dynamics of urban disease and also provide useful information for the prevention and control of visceral leishmaniasis in humans. Nas Américas, a leishmaniose visceral (LV) experimenta um processo de urbanização e o cão doméstico é considerado o principal reservatório da doença neste cenário, embora seu papel no ciclo de transmissão não esteja totalmente explicado. Este estudo teve como objetivo investigar, por meio da análise de dados espaciais e imagens de sensoriamento remoto, a relação de fatores ambientais com a ocorrência de infecção canina por Leishmania chagasi e sua correlação espacial com a doença humana na cidade de Teresina (Piauí - Brasil), onde foi relatada a primeira epidemia urbana de LV no Brasil. Os resultados são apresentados na forma de dois manuscritos, nos quais são utilizados dados georreferenciados obtidos por meio de um inquérito sorológico canino realizado durante o ano de 2011, em diferentes bairros com transmissão moderada ou intensa. No primeiro, a regressão logística multinível foi utilizada para correlacionar a prevalência da infecção canina com variáveis ambientais de quadrículas de 900m2 (30mx30m) onde os domicílios estavam localizados, ajustando para as características individuais dos cães (sexo, idade e raça) e da residência. Participaram desta análise 717 cães distribuídos em 494 domicílios e 396 quadrículas. Um percentual >16,5% da área da quadrícula coberta por pavimentação clara (ruas de terra ou asfalto antigo) foi a única variável ambiental associada com a infecção canina por L. chagasi (Odds ratio [OR] = 2,00, intervalo de 95% de confiança [IC95%]: 1,22 - 3,26). Estas áreas provavelmente correspondem àquelas mais pobres e com pior infraestrutura urbana, sugerindo a ocorrência de um padrão de transmissão intra-urbano similar aos padrões rurais e peri-urbanos da LV. No segundo manuscrito, a partir da análise hierárquica do vizinho mais próximo foi verificada a presença de sete clusters de maior concentração de cães soropositivos em relação aos soro negativos em áreas menos urbanizadas e com vegetação pouco densa. Participaram desta análise 322 cães distribuídos em cinco bairros. A relação espacial entre os caninos soropositivos e os casos humanos foi investigada através do método da distância média entre os pontos e analisada por meio do teste t. Foi encontrada uma maior proximidade de casos humanos em relação a cães soropositivos quando comparada à distância em relação aos soro negativos, sugerindo a existência de uma relação espacial entre a LV humana e a soropositividade canina. Os resultados contribuem para uma maior compreensão sobre a dinâmica da doença em meio urbano além de fornecer informações úteis para a prevenção e controle da LV em seres humanos.
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- 2013
23. Association between nutritional status and asymptomatic Leishmania infection in residents of areas endemic for visceral leishmaniasis in infantum city of Teresina, Piauí
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Gouvêa, Thaise Gasser, Werneck, Guilherme Loureiro, Hasselmann, Maria Helena, Bezerra, Flávia Fioruci, and Santos, Reinaldo Souza dos
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Visceral leishmaniasis ,Nutritional status ,Leishmaniose visceral ,Epidemiology ,Estado nutricional ,Áreas de pobreza - Teresina (PI) ,Epidemiologia ,Leishmaniose visceral - Epidemiologia - Teresina (PI) ,CIENCIAS DA SAUDE::NUTRICAO::ANALISE NUTRICIONAL DE POPULACAO [CNPQ] ,Pobres - Cuidados médicos - Abstract
Submitted by Boris Flegr (boris@uerj.br) on 2021-01-05T16:42:53Z No. of bitstreams: 1 Dissert_Thaise Gasser.pdf: 1249488 bytes, checksum: 2ccfc2c5bc5312ac5b0aa7c4a0e3d170 (MD5) Made available in DSpace on 2021-01-05T16:42:53Z (GMT). No. of bitstreams: 1 Dissert_Thaise Gasser.pdf: 1249488 bytes, checksum: 2ccfc2c5bc5312ac5b0aa7c4a0e3d170 (MD5) Previous issue date: 2012-02-24 Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro INTRODUCTION: Visceral leishmaniasis (VL) is an important neglected disease in Brazil, particularly due to its severity, geographic expansion and association with poverty. In this perspective, nutritional features emerge as elements to be considered in understanding its epidemiological pattern, potentially acting as risk factors for developing disease after infection or as prognostic factors. OBJECTIVE: To evaluate the association between nutritional status and infection by in residents of endemic areas for VL Leishmania infantum in Teresina, Piauí. METHODS: This is a cross sectional study conducted in neighborhoods of high endemicity for disease, with 198 individuals between 2 and 65 years of age. Weight and height were obtained at the household by trained staff. For adults, nutritional status was assessed by the body mass index (BMI). For children and adolescents anthropometric indexes were used (weight/age, height/age, weight/height and also BMI/age). Infection by L. infantum was evaluated using the Montenegro skin test (MST). Multivariate logistic regression was used for estimating odds ratios (OR) and respective confidence intervals (95%). RESULTS: Prevalence of asymptomatic infection was 32.6%. The prevalence of overweight was 52% among adults (BMI ? 25 kg/m²) and 23.9% among children and young people (score-z of BMI/age > 1). Subjects with overweight, both adults and those up to 19 years presented increased odds of infection of about 70% as compared to eutrophic individuals (p>0.05 for both). CONCLUSION: Although not statistically significant, the association between asymptomatic infection with L. infantum and overweight suggests that they might be at higher risk of infection due to deficits in micronutrient which are necessary for an adequate specific immune response. To test this hypothesis, longitudinal studies to evaluate the role of dietary intake and micronutrient profile in the risk of infection with L. infantum in this population are required. INTRODUÇÃO: A leishmaniose visceral (LV) é uma doença negligenciada de grande importância no cenário brasileiro, particularmente devido à sua gravidade, sua expansão geográfica e a associação com condições de pobreza. Nesta perspectiva, as condições nutricionais emergem como elementos a serem considerados na compreensão de sua situação epidemiológica, sejam como potenciais fatores de risco para o estabelecimento da doença após infecção ou como fatores associados ao prognóstico. OBJETIVO: Avaliar a associação entre estado nutricional e infecção por Leishmania infantum em moradores de áreas endêmicas para LV no município de Teresina, Piauí. MÉTODOS: Trata-se de um estudo seccional realizado em bairros de alta endemicidade para a doença, envolvendo 198 indivíduos com idade entre 2 e 65 anos. Peso e estatura foram aferidos no domicílio por profissionais treinados. Para a avaliação de adultos foi utilizado o índice de massa corporal (IMC). Para crianças e adolescentes foram avaliados os índices antropométricos (peso / idade, estatura / idade, peso / estatura e IMC / idade). A infecção por L. infantum foi avaliada a partir da intradermorreação de Montenegro (IDRM). Para a análise foi utilizada regressão logística multivariada, estimando-se razões de chances (OR) como medidas de associação e seus respectivos intervalos de confiança (95%). RESULTADOS: A prevalência de infecção assintomática foi de 32,6%. A prevalência de excesso de peso foi de 52% entre adultos (IMC ? 25 kg/m²) e de 23,9% entre crianças e jovens (escore-z de IMC / idade > 1). Indivíduos com sobrepeso, tanto adultos como aqueles de até 19 anos, apresentaram chance de infecção cerca de 70% maior quando comparados aos eutróficos (p>0,05 para ambos). CONCLUSÃO: Ainda que não estatisticamente significante, a associação entre infecção assintomática por L. infantum e sobrepeso sugere que estes indivíduos possam estar sob maior risco de infecção por apresentarem déficits de micronutrientes relevantes para a resposta imune específica. Para investigar esta hipótese, são necessários estudos longitudinais que investiguem o papel do consumo alimentar e do perfil de micronutrientes desta população no risco de infecção por L. infantum.
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- 2012
24. Evaluation of control actions of visceral leishmaniasis in the city of Teresina, Piauí State, Brazil - 2006 to 2008
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Rebouças, Fábio Augusto Costa Ferreira, Werneck, Guilherme Loureiro, Costa, Antonio José Leal, Valente, Joaquim Gonçalves, and Thomé, Sandra Maria Gomes
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Visceral Leishmaniasis ,Controle ,Calazar ,Control ,Leishmaniose Visceral ,CIENCIAS DA SAUDE::SAUDE COLETIVA::EPIDEMIOLOGIA [CNPQ] - Abstract
Submitted by Boris Flegr (boris@uerj.br) on 2020-07-05T16:02:55Z No. of bitstreams: 2 DISSERTACAO - Reboucas, Fabio Augusto Costa Ferreira (RESTRICAO).pdf: 296057 bytes, checksum: 1ca62c1fa64acd545752d6082257614f (MD5) DISSERTACAO - Reboucas, Fabio Augusto Costa Ferreira.pdf: 722922 bytes, checksum: cdf6d6edae8c967efe7cefa8375d2985 (MD5) Made available in DSpace on 2020-07-05T16:02:55Z (GMT). No. of bitstreams: 2 DISSERTACAO - Reboucas, Fabio Augusto Costa Ferreira (RESTRICAO).pdf: 296057 bytes, checksum: 1ca62c1fa64acd545752d6082257614f (MD5) DISSERTACAO - Reboucas, Fabio Augusto Costa Ferreira.pdf: 722922 bytes, checksum: cdf6d6edae8c967efe7cefa8375d2985 (MD5) Previous issue date: 2011-05-16 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior Although visceral leishmaniasis (VL) surveillance and control activities as recommended by the Brazilian Ministry of Health have been implemented in different endemic areas of the country, their results have not been satisfactory. To contain the spread of the disease, particularly considering its recent increase in transmission in urban centers, the strategy currently in use in Brazil for controlling VL deserves reassessment. This study analyzed data concerning the control actions of the Program for the Control of Visceral Leishmaniasis (PCL) developed between the years 2006 to 2008 in 38 of the 113 districts that make up the city of Teresina, Piauí State, Brazil. The PCL control actions (household insecticide spraying and culling of infected dogs) were evaluated at each three months and the outcome variable was the number of cases of VL occurring one year after. In te analysis were included also the year in which the PCL actions were performed and socio-economic variables. of their implementation. Poisson regression models were performed to verify the degree of association between the occurrence of VL and different combinations of control measures implemented by PCL in different canine prevalence scenarios (higher or lower than 10%). Results from multivariate analysis suggest non-effectiveness of control measures when not stratifying by canine prevalence. However, when stratifying by canine prevalence it is observed that in places where the prevalence is low (
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- 2011
25. Development and validation of a predective model and assessment of accuracy of diagnostic tests by means of latent class for parasitism by Leishmania chagasi in dogs admitted at the Veterinary Hospital of the Federal University of Piauí, Teresina, Brazil
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Gouvêa, Marcus Vinicius, Werneck, Guilherme Loureiro, Costa, Antonio José Leal, Figueiredo, Fabiano Borges, Braga, Jose Ueleres, and Santos, Reinaldo Souza dos
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Visceral leishmaniasis ,Modelo preditivo ,Classe latente ,Predictive model ,Leishmaniose visceral ,Latent class analysis ,Diagnóstico ,CIENCIAS DA SAUDE::SAUDE COLETIVA [CNPQ] ,Diagnostic - Abstract
Submitted by Boris Flegr (boris@uerj.br) on 2020-08-02T16:50:49Z No. of bitstreams: 1 MarcusGouveaTese 2011.pdf: 601929 bytes, checksum: 4ac6f2a73849716465206e04a142cf8a (MD5) Made available in DSpace on 2020-08-02T16:50:49Z (GMT). No. of bitstreams: 1 MarcusGouveaTese 2011.pdf: 601929 bytes, checksum: 4ac6f2a73849716465206e04a142cf8a (MD5) Previous issue date: 2011-04-30 American visceral leishmaniasis (AVL) is an expanding disease in Brazil, for which few, and apparently inefficient, control strategies are available. A major problem for the containment of visceral leishmaniasis is the lack of an accurate test for the identification of infected dogs, which are considered the main reservoirs of the disease in urban areas. In this sense, the characterization of clinical and laboratory markers of the infection in this reservoir, as well as, a more appropriate assessment of the performance of tests for the diagnosis of infection, might increase the effectiveness of control strategies for AVL. Thus, this study has two main objectives: (1) to develop and validate a prediction model for parasitism by Leishmania chagasi in dogs, based on the results of serological tests and clinical signs and (2) to evaluate the sensitivity and specificity of a clinical criterion, and of parasitological and serological tests for canine infection by L. chagasi using latent class analysis. The first goal was developed from a study in which clinical, serological and parasitological data were obtained for all dogs, suspicious or not to AVL, admitted at the Veterinary Hospital at the Federal University of Piauí, Teresina, in the years of 2003 and 2004, totaling 1412 animals. Logistic regression models were constructed with the animals admitted in 2003 with the aim of developing a predictive model for parasitism based on clinical signs and results of serology by indirect immunofluorescence (IIF). This model was validated in dogs admitted at the hospital in 2004. To evaluate the area under the ROC curve (AuROC), sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and overall accuracy, three models were developed: one based only on clinical variables, other only with the serological results and a final model based on both the clinical and serological data. Among the three, the last model showed the best performance (AuROC=90.1%, sensitivity 82.4%, specificity=81.6%, PPV=73.4% NPV=88.2% and overall accuracy=81.9%). It is concluded that the use of predictive models based on clinical and serological data for diagnosis of canine visceral leishmaniasis might be useful in the evaluation of canine infection, allowing the anticipation of ontainment of these animals in order to reduce transmission levels. The second goal was developed through a cross-sectional study of 715 dogs aged between 1 month and 13 years, with varied races evaluated by veterinarians at VUH-UFPI in the period January to December 2003. The sensitivities and specificities of clinical, parasitological and serological tests for detection of canine infection by Leishmania chagasi were estimated using latent class analysis, considering four types of models and different cutoffs. The best sensitivity estimates for the clinical, serological and parasitological tests were 60%, 95% and 66% respectively. The best estimates for the specificity of clinical, serological and parasitological tests were 77%, 90% and 100% respectively. It is concluded that the use of parasitological assays as the gold standard for validation of diagnostic tests is not appropriate and that the indicators of accuracy of the tests evaluated are insufficient to justify that they are used alone for diagnosis of infection in order to control the disease. A leishmaniose visceral americana (LVA) é uma doença em expansão no Brasil, para a qual se dispõem de poucas, e aparentemente ineficientes, estratégias de controle. Um dos grandes problemas para a contenção da leishmaniose visceral americana é a falta de um método acurado de identificação dos cães infectados, considerados os principais reservatórios da doença no meio urbano. Neste sentido, a caracterização de marcadores clínico-laboratoriais da infecção neste reservatório e a avaliação mais adequada do desempenho de testes para diagnóstico da infecção podem contribuir para aumentar a efetividade das estratégias de controle da LVA. Com isso, o presente estudo tem dois objetivos principais: (1) desenvolver e validar um modelo de predição para o parasitismo por Leishmania chagasi em cães, baseado em resultados de testes sorológicos e sinais clínicos e (2) avaliar a sensibilidade e especificidade de critérios clínicos, sorológicos e parasitológicos para detecção de infecção canina por L. chagasi mediante análise de classe latente. O primeiro objetivo foi desenvolvido a partir de estudo em que foram obtidos dados de exames clínico, sorológico e parasitológico de todos os cães, suspeitos ou não de LVA, atendidos no Hospital Veterinário Universitário da Universidade Federal do Piauí (HVU-UFPI), em Teresina, nos anos de 2003 e 2004, totalizando 1412 animais. Modelos de regressão logística foram construídos com os animais atendidos em 2003 com a finalidade de desenvolver um modelo preditivo para o parasitismo com base nos sinais clínicos e resultados de sorologia por Imunofluorescência Indireta (IFI). Este modelo foi validado nos cães atendidos no hospital em 2004. Para a avaliação da área abaixo da curva ROC (auROC), sensibilidade, especificidade, valores preditivos positivo (VPP), valores preditivos negativo (VPN) e acurácia global, foram criados três modelos: um somente baseado nas variáveis clínicas, outro considerando somente o resultado sorológico e um último considerando conjuntamente a clínica e a sorologia. Dentre os três, o último modelo apresentou o melhor desempenho (auROC=90,1%, sensibilidade=82,4%, especificidade=81,6%, VPP=73,4%, VPN=88,2% e acurácia global=81,9%). Conclui-se que o uso de modelos preditivos baseados em critérios clínicos e sorológicos para o diagnóstico da leishmaniose visceral canina pode ser de utilidade no processo de avaliação da infecção canina, promovendo maior agilidade na contenção destes animais com a finalidade de reduzir os níveis de transmissão. O segundo objetivo foi desenvolvido por meio de um estudo transversal com 715 cães de idade entre 1 mês e 13 anos, com raça variada avaliados por clínicos veterinários no HVU-UFPI, no período de janeiro a dezembro de 2003. As sensibilidades e especificidades de critérios clínicos, sorológicos e parasitológicos para detecção de infecção canina por Leishmania chagasi foram estimadas por meio de análise de classe latente, considerando quatro modelos de testes e diferentes pontos de corte. As melhores sensibilidades estimadas para os critérios clínico, sorológico e parasitológico foram de 60%, 95% e 66%, respectivamente. Já as melhores especificidades estimadas para os critérios clínico, sorológico e parasitológico foram de 77%, 90% e 100%, respectivamente. Conclui-se que o uso do exame parasitológico como padrão-ouro para validação de testes diagnósticos não é apropriado e que os indicadores de acurácia dos testes avaliados são insuficientes e não justificam que eles sejam usados isoladamente para diagnóstico da infecção com a finalidade de controle da doença.
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- 2011
26. Identification of risk areas for visceral leishmaniasis in Teresina, Piaui State, Brazil
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Almeida, Andréa Sobral de, Werneck, Guilherme Loureiro, Medronho, Roberto de Andrade, Junger, Washington Leite, Struchiner, Claudio José, Correia, Virgínia Ragoni de Moraes, and Santos, Reinaldo Souza dos
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Visceral leishmaniasis ,Public health ,Sistema de Informação Geográfica (SIG) ,Leishmaniose visceral ,Preditive models ,Geographic Information Systems (GIS) ,Epidemiology. Public health surveillance ,Remote sensing ,Modelos preditivos ,CIENCIAS DA SAUDE::SAUDE COLETIVA::EPIDEMIOLOGIA [CNPQ] ,Vigilância em saúde pública ,Multivariate analysis ,Saúde pública ,Análise multivariada ,Sensoriamento remoto ,Epidemiologia - Abstract
Submitted by Boris Flegr (boris@uerj.br) on 2020-08-02T16:50:39Z No. of bitstreams: 1 AndreaAlmeidaTese_final_08jun2011.pdf: 2335504 bytes, checksum: a468df1224373ba05c56ef44ba3149c7 (MD5) Made available in DSpace on 2020-08-02T16:50:39Z (GMT). No. of bitstreams: 1 AndreaAlmeidaTese_final_08jun2011.pdf: 2335504 bytes, checksum: a468df1224373ba05c56ef44ba3149c7 (MD5) Previous issue date: 2011-04-28 Fundação Carlos Chagas Filho de Amparo a Pesquisa do Estado do Rio de Janeiro The objective of this Thesis was to detect and characterize areas under high risk of visceral leishmaniasis (VL) and to describe patterns of occurrence and diffusion of the disease, between the years of 1993 1996 and 2001 the 2006, in Teresina, Piauí, Brazil, using statistical methods for spatial data analysis, geographic information systems and remote sensing. The results of this study are presented in three manuscripts. The first used spatial analysis to identify areas at greatest risk of VL in the urban area of Teresina, Brazil from 2001 to 2006. The results from kernel ratios showed that peripheral census tracts were the most heavily affected. Local spatial analysis showed that in the beginning of the study period local clusters of high incidence of VL were mostly located in the South and Northeast parts of the city, but in the following years those clusters appeared also in the North region of the city, suggesting that the pattern of VL occurrence is not static and disease may occasionally spread out to other areas of the municipality. The second study aimed to characterize and predict areas at high risk for occurrence of VL in Teresina, based on socioeconomic and environmental indicators obtained by remote sensing. The results of object-oriented classification indicate the expansion of the urban area to the periphery of the city, where larger areas covered by vegetation were usually seen. The model developed was able to discriminate 15 subsets of census tracts (SC) with different probabilities of containing SC with high risk of VL occurrence. The subset with higher probability of containing SC with high risk of VL (92%) encompassed SC with percentage of literate heads-of-households less than the median (≤64.2%), with greater area covered by dense vegetation, with percentage of up to 3 people per household above the third quartile (>31.6%). The model presented, respectively, in the validation and training samples, sensitivity of 79% and 54%, specificity of 75% and 71% global accuracy of 75% and 67% and area under the ROC curve of 83% and 66%. The third manuscript aimed to evaluate the applicability of object-oriented classification in searching for possible indicators of "land cover" related to the occurrence of VL on the urban environment. Accuracy indices were high for both images (>90%). In the correlation analysis, the incidence of VL was found to be positively correlated with dense vegetation, vegetation and exposed soil and negatively correlated with water, dense urban and green urban indicators, all statistically significant. The results of this thesis reveal that the occurrence of VL on the periphery of Teresina is intensely related to inadequate socioeconomic conditions and environmental modifications arising from the process of urban expansion, both favoring the occurrence of the vector (Lutzomyia longipalpis) in these regions. O propósito desta Tese foi detectar e caracterizar áreas sob alto risco para leishmaniose visceral (LV) e descrever os padrões de ocorrência e difusão da doença, entre os anos de 1993 a 1996 e 2001 a 2006, em Teresina, Piauí, por meio de métodos estatísticos para análise de dados espaciais, sistemas de informações geográficas e imagens de sensoriamento remoto. Os resultados deste estudo são apresentados na forma de três manuscritos. O primeiro usou análise de dados espaciais para identificar as áreas com maior risco de LV na área urbana de Teresina entre 2001 e 2006. Os resultados utilizando razão de kernels demonstraram que as regiões periféricas da cidade foram mais fortemente afetadas ao longo do período analisado. A análise com indicadores locais de autocorrelação espacial mostrou que, no início do período de estudo, os agregados de alta incidência de LV localizavam-se principalmente na região sul e nordeste da cidade, mas nos anos seguintes os eles apareceram também na região norte da cidade, sugerindo que o padrão de ocorrência de LV não é estático e a doença pode se espalhar ocasionalmente para outras áreas do município. O segundo estudo teve como objetivo caracterizar e predizer territórios de alto risco para ocorrência da LV em Teresina, com base em indicadores socioeconômicos e dados ambientais, obtidos por sensoriamento remoto. Os resultados da classificação orientada a objeto apontam a expansão da área urbana para a periferia da cidade, onde antes havia maior cobertura de vegetação. O modelo desenvolvido foi capaz de discriminar 15 conjuntos de setores censitário (SC) com diferentes probabilidades de conterem SC com alto risco de ocorrência de LV. O subconjunto com maior probabilidade de conter SC com alto risco de LV (92%) englobou SC com percentual de chefes de família alfabetizados menor que a mediana (≤64,2%), com maior área coberta por vegetação densa, com percentual de até 3 moradores por domicílio acima do terceiro quartil (>31,6%). O modelo apresentou, respectivamente, na amostra de treinamento e validação, sensibilidade de 79% e 54%, especificidade de 74% e 71%, acurácia global de 75% e 67% e área sob a curva ROC de 83% e 66%. O terceiro manuscrito teve como objetivo avaliar a aplicabilidade da estratégia de classificação orientada a objeto na busca de possíveis indicadores de cobertura do solo relacionados com a ocorrência da LV em meio urbano. Os índices de acurácia foram altos em ambas as imagens (>90%). Na correlação da incidência da LV com os indicadores ambientais verificou-se correlações positivas com os indicadores Vegetação densa, Vegetação rasteira e Solo exposto e negativa com os indicadores Água, Urbana densa e Urbana verde, todos estatisticamente significantes. Os resultados desta tese revelam que a ocorrência da LV na periferia de Teresina está intensamente relacionada às condições socioeconômicas inadequadas e transformações ambientais decorrentes do processo de expansão urbana, favorecendo a ocorrência do vetor (Lutzomyia longipalpis) nestas regiões.
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- 2011
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