Luis Iván Ortiz Valencia

A epidemia de dengue/dengue hemorrágico no município do Rio de Janeiro, 2001/2002

The following study was intended to evaluate the occurrence of typical signs and symptoms in the cases of classic dengue and hemorrhagic dengue fever, during the 2001-2002 epidemic in the city of Rio de Janeiro. The authors reviewed 155,242 cases notified to the Information System of Notification Diseases, from January/2001 to June/2002: 81,327 cases were classified as classic dengue and 958 as hemorrhagic dengue fever, with a total of 60 deaths. Common symptoms, such as fever, headache, prostration, myalgia, nausea and retro-orbital pain, had a high incidence in both classic and hemorrhagic dengue fever. On the other hand, hemorrhagic signs and other signs of severe disease, such as shock, gastrointestinal bleeding, petechiae, epistaxis, abdominal pain and pleural effusion, were strongly associated to hemorrhagic dengue fever. Besides, the occurrence of death was 34.8 times higher in hemorrhagic dengue fever than in classic dengue (OR = 34.8; CI 19.7-61.3).

Spatial analysis of dengue and the socioeconomic context of the city of Rio de Janeiro (Southeastern Brazil)

OBJETIVO: Analizar la epidemia de dengue con relacion al contexto socioeconomico segun areas geograficas. METODOS: Fue realizado estudio ecologico en el municipio de Rio de Janeiro (Sureste de Brasil), en areas delimitadas como urbanizaciones, a partir de informaciones de casos de dengue notificados y residentes en el municipio. Fue calculada la tasa de incidencia promedio de dengue entre las semanas epidemiologicas: 48a de 2001 a 20a de 2002. La ocurrencia de dengue fue correlacionada con variables socioeconomicas utilizandose el coeficiente de correlacion de Pearson. Se utilizo el Indice de Moran global y local para evaluar la autocorrelacion espacial del dengue y de las variables correlacionadas significativamente con la enfermedad. Fueron usados el modelo de regresion lineal multiple y el modelo espacial condicional auto-regresivo para analizar la relacion entre dengue y contexto socioeconomico. RESULTADOS: Las urbanizaciones de la zona oeste del municipio presentaron elevadas tasas de incidencia promedio de dengue. Presentaron correlacion significativa las variables: porcentaje de domicilios ligados a la red sanitaria general, domicilios con lavadora de ropas y densidad poblacional por area urbana. El indice de autocorrelacion espacial Moran revelo dependencia espacial entre el dengue y variables seleccionadas. Los modelos utilizados apuntaron el porcentaje de domicilios ligados a la red sanitaria general como unica variable asociada significativamente a la enfermedad. Los residuos de ambos modelos revelaron autocorrelacion espacial significativa, con indice de Moran positivo (p<0,001) para el de regresion y negativo (p=0,005) para el espacial condicional auto-regresivo. CONCLUSIONES: Problemas relacionados al saneamiento basico contribuyen decisivamente para el aumento del riesgo de la enfermedad.

Análise espacial da dengue e o contexto socioeconômico no município do Rio de Janeiro, RJ

OBJETIVO: Analizar la epidemia de dengue con relacion al contexto socioeconomico segun areas geograficas. METODOS: Fue realizado estudio ecologico en el municipio de Rio de Janeiro (Sureste de Brasil), en areas delimitadas como urbanizaciones, a partir de informaciones de casos de dengue notificados y residentes en el municipio. Fue calculada la tasa de incidencia promedio de dengue entre las semanas epidemiologicas: 48a de 2001 a 20a de 2002. La ocurrencia de dengue fue correlacionada con variables socioeconomicas utilizandose el coeficiente de correlacion de Pearson. Se utilizo el Indice de Moran global y local para evaluar la autocorrelacion espacial del dengue y de las variables correlacionadas significativamente con la enfermedad. Fueron usados el modelo de regresion lineal multiple y el modelo espacial condicional auto-regresivo para analizar la relacion entre dengue y contexto socioeconomico. RESULTADOS: Las urbanizaciones de la zona oeste del municipio presentaron elevadas tasas de incidencia promedio de dengue. Presentaron correlacion significativa las variables: porcentaje de domicilios ligados a la red sanitaria general, domicilios con lavadora de ropas y densidad poblacional por area urbana. El indice de autocorrelacion espacial Moran revelo dependencia espacial entre el dengue y variables seleccionadas. Los modelos utilizados apuntaron el porcentaje de domicilios ligados a la red sanitaria general como unica variable asociada significativamente a la enfermedad. Los residuos de ambos modelos revelaron autocorrelacion espacial significativa, con indice de Moran positivo (p<0,001) para el de regresion y negativo (p=0,005) para el espacial condicional auto-regresivo. CONCLUSIONES: Problemas relacionados al saneamiento basico contribuyen decisivamente para el aumento del riesgo de la enfermedad.

Diferenças clínicas observadas em pacientes com dengue causadas por diferentes sorotipos na epidemia de 2001/2002, ocorrida no município do Rio de Janeiro

The authors evaluated clinical and epidemiological differences among the serotypes of dengue in Rio de Janeiros 2001-2002 outbreak of the disease. Out of 362 cases that had viral isolation samples, notified by the Information System for Notification Diseases (SINAN), from January/2001 to June/2002, 62 were caused by serotype 1,62 by serotype 2 and 238 by serotype 3. In comparison with serotype 2, an individual infected by serotype 3 had a 6.07 times higher chance (OR = 6.07; CI: 1.10-43.97) of presenting shock and a 3.55 times higher chance (OR = 3.55; CI: 1.28-9.97) of developing exanthema. When compared to serotype 1, serotype 3 had a 3.06 times higher chance (OR = 3.06; CI: 0.99-9.66) of causing abdominal pain and a 3.61 times higher chance of exanthema (OR = 3.61; CI: 1.16-11.51). It was found that individuals infected by serotype 3 of the virus presented signs indicating a more severe disease.

Modelagem geoestatística da infecção por Ascaris lumbricoides

The following study intends to model the spatial distribution of ascariasis, through the use of geoprocessing and geostatistic analysis. The database used in the study was taken from the PAISQUA project, including a coproparasitologic and domiciliary survey, conducted in 19 selected census tracts of Rio de Janeiro State, Brazil, randomly selecting a group of 1,550 children aged 1 to 9 years old plotting them in their respective domiciles centroids. Risk maps of Ascaris lumbricoides were generated by indicator kriging. The estimated and observed values from the cross-validation were compared using a ROC curve. An isotropic spherical semivariogram model with a range of 30m and nugget effect of 50% was employed in ordinary indicator kriging to create a map of probability of A. lumbricoides infection. The area under the ROC curve indicated a significant global accuracy. The occurrence of disease could be estimated in the study area, and a risk map was elaborated through the use ordinary kriging. The spatial statistics analysis has proven itself adequate for predicting the occurrence of ascariasis, unrestricted to the regions political boundaries.

Análise espacial da soroprevalência da hepatite A em crianças de uma região carente de Duque de Caxias, RJ, Brasil

Os autores estimaram areas de risco para hepatite A em quatro setores censitarios de Duque de Caxias, Rio de Janeiro, area de intervencao ambiental do Programa de Despoluicao da Baia de Guanabara, a partir de um inquerito de soroprevalencia para hepatite A em criancas residentes nesta localidade. A amostra consistiu de 454 criancas com idade entre 1 e 9 anos, selecionadas atraves de amostra aleatoria simples em cada grupo etario. Foram coletadas aliquotas de sangue para deteccao de anticorpos totais para hepatite A pela tecnica de ELISA. Entrevistas domiciliares foram realizadas para obtencao de informacoes sobre as condicoes fisicas e sanitarias dos domicilios e peridomicilios, assim como as condicoes socioeconomicas das familias. Com a utilizacao de tecnicas geoestatisticas, foi possivel definir areas de risco para a ocorrencia da hepatite A de forma mais precisa, nao se restringindo apenas aos limites dos setores censitarios da regiao de estudo.

Spatial distribution and socioeconomic context of tuberculosis in Rio de Janeiro, Brazil

OBJECTIVE To analyze the spatial distribution of risk for tuberculosis and its socioeconomic determinants in the city of Rio de Janeiro, Brazil. METHODS An ecological study on the association between the mean incidence rate of tuberculosis from 2004 to 2006 and socioeconomic indicators of the Censo Demográfico (Demographic Census) of 2000. The unit of analysis was the home district registered in the Sistema de Informação de Agravos de Notificação (Notifiable Diseases Information System) of Rio de Janeiro, Southeastern Brazil. The rates were standardized by sex and age group, and smoothed by the empirical Bayes method. Spatial autocorrelation was evaluated by Moran’s I. Multiple linear regression models were studied and the appropriateness of incorporating the spatial component in modeling was evaluated. RESULTS We observed a higher risk of the disease in some neighborhoods of the port and north regions, as well as a high incidence in the slums of Rocinha and Vidigal, in the south region, and Cidade de Deus, in the west. The final model identified a positive association for the variables: percentage of permanent private households in which the head of the house earns three to five minimum wages; percentage of individual residents in the neighborhood; and percentage of people living in homes with more than two people per bedroom. CONCLUSIONS The spatial analysis identified areas of risk of tuberculosis incidence in the neighborhoods of the city of Rio de Janeiro and also found spatial dependence for the incidence of tuberculosis and some socioeconomic variables. However, the inclusion of the space component in the final model was not required during the modeling process.

Estimativa de áreas de risco para hepatite A

This study estimated hepatitis A risk areas in a region of Duque de Caxias, Rio de Janeiro State, Brazil. A cross-sectional study consisting of a hepatitis A serological survey and a household survey were conducted in 19 census tracts. Of these, 11 tracts were selected and 1,298 children from one to ten years of age were included in the study. Geostatistical techniques allowed modeling the spatial continuity of hepatitis A, non-use of filtered drinking water, time since installation of running water, and number of water taps per household and their spatial estimation through ordinary and indicator kriging. Adjusted models for the outcome and socioeconomic variables were isotropic; risk maps were constructed; cross-validation of the four models was satisfactory. Spatial estimation using the kriging method detected areas with increased risk of hepatitis A, independently of the urban administrative area in which the census tracts were located.

Spatial ascariasis risk estimation using socioeconomic variables.

Abstract Frequently, disease incidence is mapped as area data, for example, census tracts, districts or states. Spatial disease incidence can be highly heterogeneous inside these areas. Ascariasis is a highly prevalent disease, which is associated with poor sanitation and hygiene. Geostatistics was applied to model spatial distribution of Ascariasis risk and socioeconomic risk events in a poor community in Rio de Janeiro, Brazil. Data were gathered from a coproparasitologic and a domiciliary survey in 1550 children aged 1–9. Ascariasis risk and socioeconomic risk events were spatially estimated using Indicator Kriging. Cokriging models with a Linear Model of Coregionalization incorporating one socioeconomic variable were implemented. If a housewife attended school for less than four years, the non-use of a home water filter, a household density greater than one, and a household income lower than one Brazilian minimum wage increased the risk of Ascariasis. Cokriging improved spatial estimation of Ascariasis risk areas when compared to Indicator Kriging and detected more Ascariasis very-high risk areas than the GIS Overlay method.

Análisis espacial del dengue y el contexto socioeconómico en el municipio de Rio de Janeiro, Sureste de Brasil

OBJETIVO: Analizar la epidemia de dengue con relacion al contexto socioeconomico segun areas geograficas. METODOS: Fue realizado estudio ecologico en el municipio de Rio de Janeiro (Sureste de Brasil), en areas delimitadas como urbanizaciones, a partir de informaciones de casos de dengue notificados y residentes en el municipio. Fue calculada la tasa de incidencia promedio de dengue entre las semanas epidemiologicas: 48a de 2001 a 20a de 2002. La ocurrencia de dengue fue correlacionada con variables socioeconomicas utilizandose el coeficiente de correlacion de Pearson. Se utilizo el Indice de Moran global y local para evaluar la autocorrelacion espacial del dengue y de las variables correlacionadas significativamente con la enfermedad. Fueron usados el modelo de regresion lineal multiple y el modelo espacial condicional auto-regresivo para analizar la relacion entre dengue y contexto socioeconomico. RESULTADOS: Las urbanizaciones de la zona oeste del municipio presentaron elevadas tasas de incidencia promedio de dengue. Presentaron correlacion significativa las variables: porcentaje de domicilios ligados a la red sanitaria general, domicilios con lavadora de ropas y densidad poblacional por area urbana. El indice de autocorrelacion espacial Moran revelo dependencia espacial entre el dengue y variables seleccionadas. Los modelos utilizados apuntaron el porcentaje de domicilios ligados a la red sanitaria general como unica variable asociada significativamente a la enfermedad. Los residuos de ambos modelos revelaron autocorrelacion espacial significativa, con indice de Moran positivo (p<0,001) para el de regresion y negativo (p=0,005) para el espacial condicional auto-regresivo. CONCLUSIONES: Problemas relacionados al saneamiento basico contribuyen decisivamente para el aumento del riesgo de la enfermedad.