Andréa Sobral de Almeida

Identification of Risk Areas for Visceral Leishmaniasis in Teresina, Piaui State, Brazil

This study used spatial analysis to identify areas at greatest risk of visceral leishmaniasis (VL) in the urban area of Teresina, Brazil during 2001-2006. 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 southern and northeastern parts of the city, but in subsequent years those clusters also appeared in the northern region of the city, suggesting that the pattern of VL is not static, and the disease may occasionally spread to other areas of the municipality. We also observed a spatial correlation between VL rates and all socioeconomic and demographic indicators evaluated (P < 0.01). The concentration of interventions in high-risk areas could be an effective strategy to control the disease in the urban setting.

Potential spread of schistosomiasis in the periphery of greater metropolitan region of Rio de Janeiro

In Brazil and other developing countries, theprocess of land occupation resulting from the pre-vailing economic development model and the ex-isting social inequalities superimposed on a terri-torial base have produced a major impact on theepidemiological profile of endemic diseases.The introduction of schistosomiasis in Brazilhas been historically attributed to the arrival of thefirst African slaves in the mid-16th century. Fromthe main gateways they were taken to the sugarcane cultivation in the coastal area of northeasternBrazil, where ecological conditions werefavourable for establishing schistosomiasis. Fromthere, the endemic area gradually expanded north-wards and southwards with other agricultural crops.The district of Santa Cruz is located in the westarea of Rio de Janeiro and in order to better under-stand the occupation of this area it is important tohighlight certain relevant historical aspects. Refer-ring once again to the Colonial Period of Brazil,the arrival of the first Jesuit missionaries in the late16th century gave rise to farming and cattle-rais-ing in the area, previously considered inadequatefor such economic activities because of its pecu-liar peat bog terrain, prone to flooding. These natu-ral difficulties were overcome with the develop-ment of an efficient drainage system includingdikes, ditches, and canals. Economic growth inSanta Cruz lasted until 1760 when the Jesuits werebanned from Brazil.In the last four decades it was observed a con-tinuous migration into the Santa Cruz IndustrialDistrict, with no adequate land use planning, thesilting-in of ditches and canals, a phenomenon thatactually began when the Jesuits were expelled fromthe area, became worse in the recent years of in-dustrial development, finally leading to a severeflood of the entire Santa Cruz Lowland during theheavy rains in the summer of 1996.With these heavy rains came an outbreak ofleptospirosis and fieldwork teams from the Brazil-ian National Health Foundation (FNS) were calledinto the area. While these FNS teams were in thearea they noticed an unusually large number ofsnails in both the existing water bodies and floodareas, including peridomiciliary areas.Based on the above-mentioned observation, webegan collaborating with the FNS in studies tomonitor the presence of individuals infected withSchistosoma mansoni, the existence of autochtho-nous cases, and the identification of the intermedi-ate host species, as well as the positive infectionrate in the latter.The first step was to search for the possibletransmission area. This was done by examining arelative small number of faecal specimens from asuspected area where 200 individuals were exam-ined and three were found positive for S. mansoni.The limits of the study area were fixed to in-clude the areas with the greatest concentration ofrecent land invasions, a quadrangle of which theborders were the Ita, Goiaba, Pau da Flecha andVala da Goiaba canals.In initial parasitological survey a sample of thepopulation were selected and school-children fromthree local schools were chosen. The work alsoinvolved setting up a field laboratory in one of thepublic schools.From the stool examination of 1929 school-children, the following helminth prevalence wasfound: 2% for S. mansoni, 56% for Ascarislumbricoides, 32% for Ancylostoma sp., and 55%for Trichuris trichiura.A study on snails population dynamics was alsoperformed with monthly captures in all the waterbodies, both perennial and seasonal. In the latterthe captures were performed until the breeding

Association among house infestation index, dengue incidence, and sociodemographic indicators: surveillance using geographic information system.

BackgroundWe identified dengue transmission areas by using the Geographic Information Systems located at local surveillance units of the Itaboraí municipality in state of Rio de Janeiro. We considered the association among the house infestation index, the disease incidence, and sociodemographic indicators during a prominent dengue outbreak in 2007 and 2008.MethodsIn this ecological study, the Local Surveillance Units (UVLs) of the municipality were used as spatial pattern units. For the house analysis, we used the period of higher vector density that occurred previous to the larger magnitude epidemic range of dengue cases. The average dengue incidence rates calculated in this epidemic range were smoothed using the Bayesian method. The associations among the House Infestation Index (HI), the Bayesian rate of the average dengue incidence, and the sociodemographic indicators were evaluated using a Pearson’s correlation coefficient. The areas that were at a higher risk of dengue occurrence were detected using a kernel density estimation with the kernel quartic function.ResultsThe dengue transmission pattern in Itaboraí showed that the increase in the vector density preceded the increase in incidence. The HI was positively correlated to the Bayesian dengue incidence rate (r = 0.641; p = 0.01). The higher risk areas were those that were close to the main highways. In the Kernel density estimation analysis, we observed that the regions that were at a higher risk of dengue were those that were located in the UVLs and had the highest population densities; these locations were typically located along major highways. Four nuclei were identified as epicenters of high risk.ConclusionsThe spatial analysis units used in this research, i.e., UVLs, served as a methodological resource for examining the compatibility of different information sources concerning the disease, the vector indices, and the municipal sociodemographic aspects and were arranged in distinct cartographic bases. Dengue is a multi-scale geographic phenomenon, and using the UVLs as analysis units made it possible to differentiate the dengue occurrence throughout the municipality. The methodological approach used in this research helped improve the Itaboraí municipality monitoring activities and the local territorial monitoring in other municipalities that are affected by this public health issue.

Modelo alternativo para o controle da esquistossomose: estado atual do projeto no Estado do Espírito Santo, Brasil

An intervention study for schistosomiasis control is being carried out in the county of Afonso Cláudio, state of Espírito Santo, Brazil, having begun in February 1992. This study is an alternative response to classical control methods. The project is being developed using an interdisciplinary approach and involves both research and service institutions. The organization of health services at the primary care level is part of the project. Participant observation is seen as the methodological point of departure for guiding data collection and analysis and the intervention process in local reality. Control methods are restricted to the medical treatment given to all infected individuals and to improvements in the sanitation facilities available in the area. These methods are obviously integrated with the above-mentioned social actions. Consisting of three phases - pre-control, control (intervention), and final evaluation - the project is now in its intervention phase, lasting approximately three years.

Geographic weighted regression: applicability to epidemiological studies of leprosy

INTRODUCTION Geographic information systems (GIS) enable public health data to be analyzed in terms of geographical variability and the relationship between risk factors and diseases. This study discusses the application of the geographic weighted regression (GWR) model to health data to improve the understanding of spatially varying social and clinical factors that potentially impact leprosy prevalence. METHODS This ecological study used data from leprosy case records from 1998-2006, aggregated by neighborhood in the Duque de Caxias municipality in the State of Rio de Janeiro, Brazil. In the GWR model, the associations between the log of the leprosy detection rate and social and clinical factors were analyzed. RESULTS Maps of the estimated coefficients by neighborhood confirmed the heterogeneous spatial relationships between the leprosy detection rates and the predictors. The proportion of households with piped water was associated with higher detection rates, mainly in the northeast of the municipality. Indeterminate forms were strongly associated with higher detections rates in the south, where access to health services was more established. CONCLUSIONS GWR proved a useful tool for epidemiological analysis of leprosy in a local area, such as Duque de Caxias. Epidemiological analysis using the maps of the GWR model offered the advantage of visualizing the problem in sub-regions and identifying any spatial dependence in the local study area.

Abundance of Lutzomyia longipalpis in urban households as risk factor of transmission of visceral leishmaniasis .

Urban occurrence of human and canine visceral leishmaniasis (VL) is linked to households with characteristics conducive to the presence of sand flies. This study proposes an ad hoc classification of households according to the environmental characteristics of receptivity to phlebotominae and an entomological study to validate the proposal. Here we describe the phlebotominae population found in intra- and peridomiciliary environments and analyse the spatiotemporal distribution of the VL vector Lutzomyia longipalpis of households receptive to VL. In the region, 153 households were classified into levels of receptivity to VL followed by entomological surveys in 40 of those properties. Kruskal-Wallis verified the relationship between the households’ classification and sand fly abundance and Kernel analysis evaluated L. longipalpis spatial distribution: of the 740 sand flies were captured, 91% were L. longipalpis; 82% were found peridomiciliary whilst the remaining 18% were found intradomiciliary. No statistically significant association was found between sandflies and households levels. L. longipalpis counts were concentrated in areas of high vulnerability and some specific households were responsible for the persistence of the infestation. L. longipalpis prevails over other sand fly species for urban VL transmission. The entomological study may help target the surveillance and vector control strategies to domiciles initiating and/or maintaining VL outbreaks.

Temporal and spatial evolution of maternal and neonatal mortality rates in Brazil, 1997–2012

OBJECTIVE Maternal and neonatal mortality are important public health issues in low-income countries. This study evaluated spatial and temporal maternal and neonatal mortality trends in Brazil between 1997 and 2012. METHODS This study employed spatial analysis techniques using death records from the mortality information system. Maternal mortality rates per 100,000 and neonatal mortality rates (early and late) per 1000 live births were calculated by state, region, and period (1997-2000, 2001-2004, 2005-2008, and 2009-2012). Multivariate negative binomial models were used to explain the risk of death. RESULTS The mean Brazilian maternal mortality rate was 55.63/100,000 for the entire 1997-2012 period. The rate fell 10% from 1997-2000 (58.92/100,000) to 2001-2004 (52.77/100,000), but later increased 11% during 2009-2012 (58.69/100,000). Early and late neonatal mortality rates fell 33% (to 7.36/1000) and 21% (to 2.29/1000), respectively, during the 1997-2012 period. Every Brazilian region witnessed a drop in neonatal mortality rates. However, maternal mortality increased in the Northeast, North, and Southeast regions. CONCLUSION Brazils neonatal mortality rate has improved in recent times, but maternal mortality rates have stagnated, failing to meet the Millennium Development Goals. Public policies and intersectoral efforts may contribute to improvements in these health indicators.

Risk factors for arbovirus infections in a low-income community of Rio de Janeiro, Brazil, 2015-2016

Background Dengue epidemics have occurred in the city of Rio de Janeiro (Brazil) since 1986. In the year 2015, Zika and chikungunya viruses were introduced in the city, causing sequential and simultaneous epidemics. Poor socioeconomic conditions have been suggested as contributing factors of arboviral infection. Objective To describe the spatial distribution of human cases of symptomatic arboviral infections and to identify risk factors for infection in a poor community of Rio de Janeiro in the years 2015 and 2016. Methods We built thematic maps of incidence rates for 78 micro-areas in the Manguinhos neighborhood. The micro-areas congregate about 600 inhabitants. Simple and multiple multilevel logistic regression models were used to evaluate the association between the incidence of arboviral diseases and socio-demographic factors at both the individual and micro-area levels. Results From 2015 to 2016, 370 human cases of arbovirus infection were reported in the Manguinhos community: 123 in 2015 and 247 in 2016. There was a significant difference in the risk of arbovirus diseases among different micro-areas, but this was not explained by water and sanitation indicators. The cumulative incidence rate was 849/100,000 in two years. The incidence was greater in those individuals with familiar vulnerability (1,156/100,000 vs. 794/100,000). The multilevel adjusted model showed that the odds of acquiring an arbovirus infection was 55% greater in those with familiar vulnerability. Conclusion Arbovirus infections cause a high burden of disease in Brazilian urban centers. Our results suggest that even in poor neighborhoods, there is a high spatial variability in the risk of acquiring an arbovirus infection. The conditions that favor vector proliferation and infection by arboviruses are complex and involve both individual and environmental characteristics that vary from place to place. To reduce the burden of arboviral diseases, continued public health policies and basic services should be provided to the communities at risk that consider specific local needs.

Factors associated with Chagas disease among blood donors in Brazilian Northeast region

BACKGROUND Despite the intensification of Chagas disease control in Brazil, around 1980s and 1990s, the transmission still occurs. The aim of this study was to identify the factors associated with Chagas disease among blood donors in Piaui State, Brazilian Northeast Region from 2004 to 2013. METHODOLOGY Records of 597 blood donors from Management System in Hemotherapy Services and Laboratory Environment Manager System of Piaui were studied. Sociodemographic variables and serological tests results for Chagas diseases confirmation were analyzed using adjusted multiple logistic regression and odds ratio (OR) evaluation. RESULTS The frequency of serological test confirming Chagas disease was 15.6%. Multivariate analysis showed that the most important associated factors were among blood donors who were born until 1960 (OR 5.1; 95%; CI 1.95-13.14), with low educational level (OR 2.8; 95%; CI 0.75-10.29), who lives in cities with ≤50% of urbanization rate (OR 3.5; 95%; CI 1.42-8.72) and first-time blood donors (OR 3.0; 95%; CI 1.74-5.23). CONCLUSIONS Unfortunately, the factors associated with Chagas disease are still the same pointed out in the scientific literature of decades ago. Our results are in line with the postulate of the 2nd Brazilian Consensus on Chagas disease, regarding the need to develop research that presents new scientific evidence, contributing not only to the Brazilian scenario but also to Latin America.

Dinâmica espacial da incidência da AIDS em idosos no Rio de Janeiro, Brasil, 1997-2011

The dynamics of the spread of the AIDS epidemic ranges according to the characteristics of each geographical region in different population groups. The aim of this study was to evaluate spatial and temporal trends of the AIDS epidemic among the elderly in the State of Rio de Janeiro, Brazil. A retrospective study using spatial analysis techniques was conducted among AIDS cases (≥ 60 years) diagnosed from 1997-2011. The Poisson regression model was used to assess the relationship between year of diagnosis and incidence of AIDS, adjusted by sex. The AIDS epidemic began in the south coast of the state and gradually reached neighboring cities. The highest rates were found in regions around Rio de Janeiro and Niterói cities. The highest smoothed rates of the period were observed in Niterói in 2002-2006: 11.87/100,000 (men) and 8,5/100,000 (women). AIDS incidence rates among the elderly have stabilized in recent decades. To prevent HIV from spreading further among the general population, greater attention should be given to the older population.