ABSTRACT Background: Chagas disease (CD) is caused by Trypanosoma cruzi and transmitted by triatomines. Historical information from the 20th century demonstrates T. cruzi records in the metropolitan region of Salvador (MRS), the third largest urban agglomeration in the Brazilian Northeast and the eighth largest in Brazil, an area with intense migratory activity from CD-endemic regions. Therefore, this study aimed to evaluate CD indicators (prevalence and mortality) in the MRS. Methods: A mixed ecological and descriptive study was conducted using secondary data. We analyzed data from 2008 to 2015: deaths due to CD, self-reported cases of CD, and blood donors that were non-negative for T. cruzi infection. Results: São Francisco do Conde was one of the municipalities with the highest mortality rates due to CD. The seroprevalence rates varied by year and municipality; those with the highest values were 2008: Vera Cruz, 2009: Mata de São João, 2010: Dias D'Ávila, 2011 and 2015: São Francisco do Conde, 2012: São Sebastião do Passé, and 2013 and 2014: Pojuca. Spatial correlations between the municipalities were not detected. Conclusions: We conclude that CD is present in the MRS. The indicators analyzed in the MRS are below-state-level data. Given the importance of indicator analysis for the surveillance and control of CD at the state and national levels, it is important to strengthen the surveillance program at the municipal level, including the regions classified as low risk for T. cruzi vector transmission.

ABSTRACT Background: Neglected tropical diseases are a growing threat to global health, and endemic Chagas disease has emerged as one of the most important health problems in America. The main strategy to prevent Trypanosoma cruzi transmission is chemical control of vectors. This study presents a descriptive analysis of synanthropic triatomines before and after the implementation of a vector-control program in Bahia, Brazil. Methods: Descriptive analysis and geospatial statistics were performed on triatomine data, (1) the relative abundance and (2) proportional spatial distribution, from Bahia during two periods: (A) 1957 to 1971 and (B) 2006 to 2019. Results: We observed a decrease in the relative abundance of Panstrongylus megistus (A: n=22.032, 61.9%; B: n=1.842, 1.0%) and Triatoma infestans (A: n=1.310, 3.7%; B: n=763, 0.43%), as well as an increase in the relative abundance of T. sordida (A: n=8.314, 23.4%, B: n=146.901, 81.6%) and T. pseudomaculata (A: n=894, 2.5%, B: n=16.717, 9.3%). Conclusions: Our results indicate a clear reduction in the occurrence of P. megistus and T. infestans (last record in 2015) and an increase in the relative abundance and geographical distribution of T. sordida and T. pseudomaculata after 40 years of the vector-control program. The high frequency of other triatomine species in the municipalities of the state of Bahia and their abundance in recent years highlight the need to reinforce permanent entomological surveillance actions to prevent Chagas disease.

Abstract INTRODUCTION: Chagas disease (CD) affects 5.7-7.0 million individuals worldwide, and its prevalence reached 25.1% in the state of Bahia, Brazil. There is an association between the prevalence of CD, the socioeconomic status of the population, and the risk of re-emergence due to non-vectorial transmission, such as blood transfusion. This study determined the seroprevalence of T. cruzi infection among blood donors in the state of Bahia, located in northeastern Brazil, and their epidemiological profile during a 10-year period. METHODS: We performed a descriptive cross-sectional study involving a database review. Data were collected from patients with non-negative results for T. cruzi infection during a 10-year period. RESULTS: A total of 3,084 (0.62%) samples were non-negative for T. cruzi infection in an initial serological screening, and 810 (0.16%) samples were non-negative in the second screening. The correlation between infection and age (30 years or older) and between infection and lower educational level (12 years or less) in the first and second screening was statistically significant. The seroprevalence of T. cruzi infection was higher in men in the first screening. In addition, 99.52% of the municipalities of Bahia had at least one case of CD. Livramento de Nossa Senhora and Salvador presented the highest disease prevalence and recurrence, respectively. CONCLUSIONS: The seroprevalence of T. cruzi infection in these populations was lower than that found in other studies in Brazil but was comparatively higher in densely-populated areas. The demographic characteristics of our population agreed with previous studies.

INTRODUÇÃO: A leptospirose, enfermidade causada por uma espiroqueta patogênica do gênero Leptospira, é uma das zoonoses mais difundidas no mundo, considerada um importante problema de saúde pública. Este trabalho tem como objetivo descrever o padrão espacial da leptospirose na Cidade de Aracaju, no período de 2001 a 2007, buscando identificar as áreas de risco para ocorrência da leptospirose. MÉTODOS: Utilizou-se a razão de Kernel, que consiste na criação de uma razão entre duas superfícies, para visualizar a superfície de risco da doença, onde no numerador coloca-se os casos, georreferenciados para setor censitário, e no denominador o kernel da população dessas áreas. Através deste método, foi possível delimitar áreas de maior densidade de casos, e compará-las visualmente com fator socioeconômico, como renda média. RESULTADOS: Comparando os períodos de chuva com os períodos de seca, verificou-se que não ocorre a presença de padrão espacial semelhante nos dois períodos, não coincidindo com as áreas consideradas de maior risco para ocorrência da doença. Através dos parâmetros estabelecidos, neste estudo, foi permitido verificar a importância da aplicação de técnicas de análise espacial na área de saúde pública. CONCLUSÕES: O kernel se mostrou uma ferramenta útil na obtenção de uma análise global da situação epidemiológica da leptospirose em Aracaju, o que viabiliza sua utilização pelas secretarias de saúde municipal e estadual.

INTRODUCTION: Leptospirosis, a disease caused by pathogenic spirochetes of the genus Leptospira, is one of the most widespread zoonoses in the world and is considered an important public health problem. This paper aims to describe the spatial pattern of leptospirosis in the City of Aracaju from 2001 to 2007 in an effort to identify areas at risk for leptospirosis. METHODS: We used the ratio of Kernel, which represents the ratio between two surfaces, to visualize the surface of disease risk. The numerator corresponds to the number of cases geocoded to the census tract, and the denominator of the kernel corresponds to the population of these areas. Using this method, the areas with the highest density of cases were delineated and compared visually with socioeconomic factors, such as average income. RESULTS: The spatial pattern was different in periods of rain compared with periods of drought and did not coincide with the areas considered most at risk for the disease. This study revealed the importance of applying spatial analysis techniques in the field of public health. CONCLUSIONS: These findings indicate that the kernel is a useful tool for obtaining a comprehensive review of the epidemiology of leptospirosis in Aracaju, which supports the kernel's use by the municipal health departments and by the state.

A disseminação da esquistossomose mansônica vem desafiando o sistema de saúde brasileiro, deixando clara a necessidade da reavaliação das estratégias do programa de controle da endemia. O objetivo deste trabalho foi delimitar as áreas geográficas de risco para a esquistossomose em Lauro de Freitas, Bahia, Brasil, e estabelecer o perfil epidemiológico e socioeconômico da doença no município. Utilizou-se o estimador de densidade de Kernel para a identificação visual de aglomerados de casos e a análise de varredura espaço-temporal de Kulldorff & Nagarwalla para a obtenção de aglomerados com significância estatística e mensuração do risco. As duas técnicas identificaram quatro áreas de risco para a doença no município, com indicadores socioeconômicos mais baixos que as áreas fora dos aglomerados. A análise de correspondência múltipla mostrou um perfil diferenciado nos pacientes positivos para a esquistossomose pertencentes ao aglomerado primário. As técnicas empregadas se configuram em uma importante aquisição metodológica para a vigilância e controle da doença no município.

The spread of schistosomiasis mansoni defies efforts by Brazil's Unified National Health System, thus demonstrating the need to reassess endemic control programs in the country. The aim of this study was to demarcate geographic areas at risk of schistosomiasis in Lauro de Freitas, Bahia State, Brazil, and to establish the epidemiological and socioeconomic profile of the disease in this municipality (county). Kernel density estimator exploratory analysis was used for visual identification of areas at risk. Kulldorff & Nagarwalla's spatial analysis was used to obtain statistically significant clusters and to measure risk. These technologies identified four risk areas for schistosomiasis. Clusters identified within the risk areas were characterized by lower socioeconomic conditions. Multiple correspondence analyses showed a distinct profile for positive patients in the primary cluster. The techniques employed here represent an important methodological acquisition for tracking and controlling schistosomiasis in Lauro de Freitas.

A disseminação da esquistossomose mansônica vem desafiando o sistema de saúde brasileiro, deixando clara a necessidade da reavaliação das estratégias do programa de controle da endemia. O objetivo deste trabalho foi delimitar as áreas geográficas de risco para a esquistossomose em Lauro de Freitas, Bahia, Brasil, e estabelecer o perfil epidemiológico e socioeconômico da doença no município. Utilizou-se o estimador de densidade de Kernel para a identificação visual de aglomerados de casos e a análise de varredura espaço-temporal de Kulldorff & Nagarwalla para a obtenção de aglomerados com significância estatística e mensuração do risco. As duas técnicas identificaram quatro áreas de risco para a doença no município, com indicadores socioeconômicos mais baixos que as áreas fora dos aglomerados. A análise de correspondência múltipla mostrou um perfil diferenciado nos pacientes positivos para a esquistossomose pertencentes ao aglomerado primário. As técnicas empregadas se configuram em uma importante aquisição metodológica para a vigilância e controle da doença no município.

The spread of schistosomiasis mansoni defies efforts by Brazil's Unified National Health System, thus demonstrating the need to reassess endemic control programs in the country. The aim of this study was to demarcate geographic areas at risk of schistosomiasis in Lauro de Freitas, Bahia State, Brazil, and to establish the epidemiological and socioeconomic profile of the disease in this municipality (county). Kernel density estimator exploratory analysis was used for visual identification of areas at risk. Kulldorff & Nagarwalla's spatial analysis was used to obtain statistically significant clusters and to measure risk. These technologies identified four risk areas for schistosomiasis. Clusters identified within the risk areas were characterized by lower socioeconomic conditions. Multiple correspondence analyses showed a distinct profile for positive patients in the primary cluster. The techniques employed here represent an important methodological acquisition for tracking and controlling schistosomiasis in Lauro de Freitas.