Risk analysis for occurrences of schistosomiasis in the coastal area of Porto de Galinhas, Pernambuco, Brazil.

BACKGROUND: Manson's schistosomiasis continues to be a severe public health problem in Brazil, where thousands of people live under the risk of contracting this parasitosis. In the Northeast of Brazil, schistosomiasis has expanded from rural areas to the coast of Pernambuco State, where the intermediate host is Biomphalaria glabrata snails. This study aims at presenting situational analyses on schistosomiasis at the coastal locality of Porto de Galinhas, Pernambuco, Brazil, by determining the risk factors relating to its occurrence from the epidemiological and spatial perspectives. METHODS: In order to gather prevalence data, a parasitological census surveys were conducted in 2010 in the light of the Kato-Katz technique. Furthermore, malacological surveys were also conducted in the same years so as to define the density and infection rates of the intermediate host. Lastly, socioeconomic-behavioral survey was also conducted to determine the odds ratio for infection by Schistosoma mansoni. Based on these data, spatial analyses were done, resulting in maps of the risk of disease transmission. To predict the risk of schistosomiasis occurrence, a multivariate logistic regression was performed using R 2.13 software. RESULTS: Based on prevalence, malacological and socioeconomic-behavioural surveys, it was identified a prevalence of 15.7% in the investigated population (2,757 individuals). Due to the malacological survey, 36 breeding sites were identified, of which 11 were classified as foci of schistosomiasis transmission since they pointed out snails which were infected by Schistosoma mansoni. Overall, 11,012 snails (Biomphalaria glabrata) were collected. The multivariate regression model identified six explanatory variables of environmental, socioeconomic and demographic nature. Spatial sweep analysis by means of the Bernoulli method identified one statistically significant cluster in Salinas (RR = 2.2; p-value < 0.000), the district with the highest occurrence of cases. CONCLUSIONS: Based on the resulting information from this study, the epidemiological dimensions of this disease are significant and severe, within the scenario of schistosomiasis in Pernambuco state. The risk factors which were identified in the predictive model made it clear that the environmental and social conditions influence on the schistosomiasis occurrences.

Schistosomiasis transmission and environmental change: a spatio-temporal analysis in Porto de Galinhas, Pernambuco--Brazil.

BACKGROUND: In Brazil, schistosomiasis mansoni infection is an endemic disease that mainly affects the country's rural populations who carry out domestic and social activities in rivers and water accumulations that provide shelter for the snails of the disease. The process of rural migration to urban centers and the disorderly occupation of natural environments by these populations from endemic areas have favored expansion of schistosomiasis to locations that had been considered to be disease-free. Based on environmental changes that have occurred in consequent to an occupation and urbanization process in the locality of Porto de Galinhas, the present study sought to identify the relationship between those chances, measure by remote-sensing techniques, and establish a new endemic area for schistosomiasis on the coast of Pernambuco State--Brazil. METHODS: To gather prevalence data, two parasitological census surveys were conducted (2000 and 2010) using the Kato-Katz technique. Two malacological surveys were also conducted in the same years in order to define the density and infection rate of the intermediate host. Based on these data, spatial analyses were done, resulting in maps of the risk of disease transmission. To ascertain the environmental changes that have occurred at the locality, images from the QuickBird satellite were analyzed, thus resulting in land use maps. RESULTS: Over this 10-year period, the foci of schistosomiasis became more concentrated in the Salinas district. This area was considered to be at the greatest risk of schistosomiasis transmission and had the highest prevalence rates over this period. The study illustrated that this was the area most affected by the environmental changes resulting from the disorderly urbanization process, which gave rise to unsanitary environments that favored the establishment and maintenance of foci of schistosomiasis transmission, thereby consolidating the process of expansion and endemization of this parasitosis.

The endemisation of schistosomiasis in Porto de Galinhas, Pernambuco, Brazil, 10 years after the first epidemic outbreak.

In 2000, after heavy rains and floods in Porto de Galinhas, Pernambuco, Brazil, an outbreak of schistosomiasis was recorded, of which 62.2% (412 cases) were of the acute clinical form. Between 2001-2009, occasional findings of Biomphalaria snails parasitised by Schistosoma mansoni indicated that disease transmission was still occurring. This motivated a new epidemiological survey between August-December 2010 to provide an update of the occurrence of this health hazard and to investigate the process of disease endemisation at this locality. This survey gathered parasitological, clinical and malacological data. The results of this survey, compared with data from the year 2000 survey, showed the following: (i) over these 10 years, there were declines in the total percentage of cases and the percentage of acute forms, (ii) the acute clinical form now represents 23.3% in contrast with the 62.2% detected in 2000 and (iii) the current prevalence of schistosomiasis is 15.7%, while in 2000 32.1% of the individuals were diagnosed as parasitised. Today, the chronic clinical form represents 76.7% of the total number of cases diagnosed, thus showing that over the 10-year period the occurrences of clinical forms became inverted. These findings, together with visual observation of insalubrious environmental conditions, indicate that schistosomiasis has become endemic in Porto de Galinhas.

Using mobile technology to conduct epidemiological investigations.

INTRODUCTION: The aim of this study was to report the experience of an epidemiological field survey for which data were collected and analyzed using tablets. METHODS: The devices used Epi Info 7 (Android version), which has been modeled a database with variables of the traditional form. RESULTS: Twenty-one households were randomly selected in the study area; 75 residents were registered and completed household interviews with socioeconomic and environmental risk variables. CONCLUSIONS: This new technology is a valuable tool for collecting and analyzing data from the field, with advantageous benefits to epidemiological surveys.

Biological and environmental factors associated with risk of schistosomiasis mansoni transmission in Porto de Galinhas, Pernambuco State, Brazil.

Schistosomiasis has expanded to the coast of Pernambuco State, Brazil, where there are frequent reports of Biomphalaria glabrata snails and human cases of the disease. This study analyzes factors related to schistosomiasis transmission risk in Porto de Galinhas. A one-year malacological survey was conducted to identify biological, abiotic, and environmental factors related to the host snail breeding sites. Data analysis used Excel 2010, GTM Pro, and ArcGis 10. A total of 11,012 B. glabrata snails were captured in 36 breeding sites, and 11 schistosomiasis transmission foci were identified. A negative correlation was found between breeding site temperature and snail density and infection rate, and a positive correlation with pH and salinity. The rainy season showed a positive correlation with snail density and infection rate. The study emphasizes the factors involved in the maintenance of schistosomiasis breeding sites, in light of persistence of this disease in Porto de Galinhas for more than 10 years.

Spatial distribution of schistosomiasis and geohelminthiasis cases in the rural areas of Pernambuco, Brazil.

INTRODUCTION: The prevalence and intensity of geohelminth infections and schistosomiasis remain high in the rural areas of Zona da Mata, Pernambuco (ZMP), Brazil, where these parasites still represent a significant public health problem. The present study aimed to spatially assess the occurrences of schistosomiasis and geohelminthiasis in the ZMP. METHODS: The ZMP has a population of 1,132,544 inhabitants, formed by 43 municipalities. An ecological study was conducted, using secondary data relating to positive human cases and parasite loads of schistosomiasis and positive human cases of geohelminthiasis that were worked up in Excel 2007. We used the coordinates of the municipal headquarters to represent the cities which served as the unit of analysis of this study. The Kernel estimator was used to spatially analyze the data and identify distribution patterns and case densities, with analysis done in ArcGIS software. RESULTS: Spatial analysis from the Kernel intensity estimator made it possible to construct density maps showing that the northern ZMP was the region with the greatest number of children infected with parasites and the populations most intensely infected by Schistosoma mansoni. In relation to geohelminths, there was higher spatial distribution of cases of Ascaris lumbricoides and Trichuris trichiura in the southern ZMP, and greater occurrence of hookworms in the northern/central ZMP. CONCLUSIONS: Despite several surveys and studies showing occurrences of schistosomiasis and geohelminthiasis in the ZMP, no preventive measures that are known to have been effective in decreasing these health hazards have yet been implemented in the endemic area.

Spatial analysis of schistosomiasis human cases in the horticultural community of Zona da Mata of Pernambuco state, Brazil.

The objective of this study was to describe the spatial distribution of schistosomiasis in horticultural community of Natuba, district of Vitória de Santo Antão, Pernambuco state. It was conducted a parasitological survey, examined the fecal material of 310 community residents. The cases positive for Schistosoma mansoni were geocoded and included in the computerized template of the community, generating maps of spatial distribution with kernel estimators. The results showed a high prevalence of schistosomiasis, with 28.4% of the parasites. Other parasites were found in 25.8% of the population. The use of GIS tools to map and understand the possible distribution of cases of schistosomiasis in the space occupied by the community highlighting and listing locations of lower elevation (able to flooding), with a higher frequency of human cases. Studies like this provide information to the local health services, may intervene and bring about change for individuals living in areas with low housing conditions to minimize their exposure to risk of contracting schistosomiasis.

Epidemiologia da esquistossomose no litoral de Pernambuco / Epidemiology of schistosomiasis in coastal areas of Pernambuco State, Brazil

A expansão da esquistossomose para o litoral de Pernambuco vem sendo registrada desde 1992 coma detecção de casos agudos da doença em indivíduos de classe média/alta. Para diagnosticar estenovo cenário de transmissão da endemia em localidades turísticas na orla marítima do estado é defundamental importância o conhecimento prévio da distribuição georreferenciada das espécies demoluscos vetores, por meio de mapas que apontem sua exata localização, assim como é necessárioespacializar as situações de risco biológico e as condições ambientais insalubres. Nos períodos de 15a 18 de setembro de 2008 e 10 a 13 de setembro de 2013 foram realizadas caravanas expedicionárias,por epidemiologistas e parasitologistas por 11 municípios do litoral do estado, percorrendo todasas coleções de água doce distantes até 2 km da beira-mar. Os dados foram georreferenciados paraposterior condução de análises espaciais. Para identificação da positividade dos exemplares deBiomphalaria glabrata, foi utilizada a técnica de exposição à luz. Os espécimes de B. stramineaque permaneceram negativos até o 15º dia foram submetidos à técnica de diagnóstico molecular(PCR-single tube). Nas coletas de 2008 foram capturados 3.392 caramujos B. glabrata e 725 B.straminea, cujas taxas de infecção variaram entre 0,9 por cento a 22,2 por cento. Em 2013, foram coletados 948B. glabrata e 504 B. straminea e somente foram encontrados caramujos eliminando cercarias nalocalidade Porto de Galinhas com taxa de infectividade de 81,4 por cento, permanecendo como localidadede maior risco para transmissão da esquistossomose.

The expansion of schistosomiasis to the coast of Pernambuco has been registered since 1992 withthe detection of acute cases of the disease in individuals of middle/upper class. To diagnose thisnew scenario of transmission of schistosomiasis in tourist areas on the waterfront of the state,knowledge of georeferenced species distribution of vector snails through maps that show theirexact location seems essential, as it is necessary to localize situations with biohazard and unhealthyenvironmental conditions. From 15 to 18 September 2008 and 10 to 13 September 2013, expeditionswere conducted by groups of epidemiologists and parasitologists for 11 coastal municipalities ofthe state, checking all the collections of fresh water up to 2 km away from the seaside. Data weregeoreferenced for a later conduction of spatial analysis. For positive identification of Biomphalariaglabrata, the technique of light exposure was used. Specimens of B. straminea that remainednegative until the 15th day underwent the technique of molecular diagnosis (PCR-single tube). Inthe 2008 expedition, 3,392 B. glabrata snails and 725 B. straminea snails were captured, whose infection rates ranged from 0.9 percent to 22.2 percent. In the 2013 expedition, 948 B. glabrata and 504 B. straminea snails were collected and only in Porto de Galinhas city were B. glabrata snails found releasing S. mansoni cercariae, with an infectivity rate of 81.4 percent, confirming that in this locality the risk of schistosomiasis transmission is still present.

Biological and environmental factors associated with risk of schistosomiasis mansoni transmission in Porto de Galinhas, Pernambuco State, Brazil / Fatores biológicos e ambientais associados ao risco de transmissão da esquistossomose mansoni na localidade de Porto de Galinhas, Pernambuco, Brasil / Factores biológicos y ambientales asociados al riesgo de transmisión de la esquistosomiasis mansoni en la localidad de Porto de Galinhas, Pernambuco, Brasil

Schistosomiasis has expanded to the coast of Pernambuco State, Brazil, where there are frequent reports of Biomphalaria glabrata snails and human cases of the disease. This study analyzes factors related to schistosomiasis transmission risk in Porto de Galinhas. A one-year malacological survey was conducted to identify biological, abiotic, and environmental factors related to the host snail breeding sites. Data analysis used Excel 2010, GTM Pro, and ArcGis 10. A total of 11,012 B. glabrata snails were captured in 36 breeding sites, and 11 schistosomiasis transmission foci were identified. A negative correlation was found between breeding site temperature and snail density and infection rate, and a positive correlation with pH and salinity. The rainy season showed a positive correlation with snail density and infection rate. The study emphasizes the factors involved in the maintenance of schistosomiasis breeding sites, in light of persistence of this disease in Porto de Galinhas for more than 10 years.

A esquistossomose se expande para o litoral de Pernambuco, Brasil, onde têm sido frequente os registros de caramujos Biomphalaria glabrata e de casos humanos da doença. Este estudo apresenta fatores relacionados ao risco de transmissão da esquistossomose na localidade de Porto de Galinhas. Durante um ano, foi conduzido um inquérito malacológico para identificar fatores biológicos, abióticos e ambientais relacionados aos criadouros dos moluscos hospedeiros. Para análise dos dados, foram utilizados os softwares Excel 2010, GTM Pro e ArcGis 10. Foram coletados 11.012 caramujos B. glabrata nos 36 criadouros identificados, sendo diagnosticados 11 focos de transmissão da esquistossomose. Foi verificada correlação negativa entre a temperatura dos criadouros, densidade e taxa de infecção dos caramujos e correlação positiva para pH e salinidade. O período de chuva apresentou correlação positiva com a densidade e taxa de infecção dos moluscos. O estudo enfatiza os fatores envolvidos na manutenção dos criadouros da esquistossomose visto à persistência dessa doença na localidade de Porto de Galinhas há mais de 10 anos.

La esquistosomiasis se expande hacia el litoral de Pernambuco, Brasil, donde han sido frecuentes los registros de caracoles Biomphalaria glabrata y casos humanos de la enfermedad. Este estudio presenta factores relacionados con el riesgo de transmisión de la esquistosomiasis en la localidad Porto de Galinhas. Durante un año se llevó a cabo una investigación malacológica para identificar factores biológicos, abióticos y ambientales, relacionados con los criaderos de los moluscos huéspedes. Para el análisis de los datos se utilizaron los softwares Excel 2010, GTM Pro y ArcGis 10. Se recogieron 11.012 caracoles B. glabrata en los 36 criaderos identificados, siendo diagnosticados 11 focos de transmisión de la esquistosomiasis. Se verificó la correlación negativa entre la temperatura de los criaderos, densidad y tasa de infección de los caracoles, y la correlación positiva entre el pH y salinidad. El período de lluvia presentó una correlación positiva con la densidad y tasa de infección de los moluscos. El estudio enfatiza los factores involucrados en el mantenimiento de los criaderos de la esquistosomiasis, vista la persistencia de esta enfermedad en la localidad de Porto de Galinhas hace más de 10 años.

Spatial distribution of schistosomiasis and geohelminthiasis cases in the rural areas of Pernambuco, Brazil / Distribuição espacial dos casos de esquistossomose e geohelmintoses em áreas rurais de Pernambuco, Brasil

INTRODUCTION: The prevalence and intensity of geohelminth infections and schistosomiasis remain high in the rural areas of Zona da Mata, Pernambuco (ZMP), Brazil, where these parasites still represent a significant public health problem. The present study aimed to spatially assess the occurrences of schistosomiasis and geohelminthiasis in the ZMP. METHODS: The ZMP has a population of 1,132,544 inhabitants, formed by 43 municipalities. An ecological study was conducted, using secondary data relating to positive human cases and parasite loads of schistosomiasis and positive human cases of geohelminthiasis that were worked up in Excel 2007. We used the coordinates of the municipal headquarters to represent the cities which served as the unit of analysis of this study. The Kernel estimator was used to spatially analyze the data and identify distribution patterns and case densities, with analysis done in ArcGIS software. RESULTS: Spatial analysis from the Kernel intensity estimator made it possible to construct density maps showing that the northern ZMP was the region with the greatest number of children infected with parasites and the populations most intensely infected by Schistosoma mansoni. In relation to geohelminths, there was higher spatial distribution of cases of Ascaris lumbricoides and Trichuris trichiura in the southern ZMP, and greater occurrence of hookworms in the northern/central ZMP. CONCLUSIONS: Despite several surveys and studies showing occurrences of schistosomiasis and geohelminthiasis in the ZMP, no preventive measures that are known to have been effective in decreasing these health hazards have yet been implemented in the endemic area.

INTRODUÇÃO: A prevalência e intensidade das infecções produzidas por geohelmintos e esquistossomose continuam elevadas na Zona da Mata de Pernambuco (ZMP), onde essas parasitoses se apresentam como relevante problema de saúde pública. O presente estudo objetivou espacializar a ocorrência da esquistossomose e geohelmintoses na ZMP. MÉTODOS: A ZMP apresenta uma população de 1.132.544 habitantes, composta por 43 municípios. Um estudo ecológico foi desenvolvido, utilizando dados secundários referentes aos casos humanos positivos e cargas parasitárias para esquistossomose e casos humanos positivos para geohelmintoses que foram trabalhados no Excel 2007. Foram utilizadas as coordenadas das sedes municipais para representar o município o qual serviu de unidade de análise deste estudo. Para análise espacial dos dados e identificação de padrões de distribuição e densidade dos casos, foi adotado o estimador de Kernel, sendo as análises feitas no software ArcGIS. RESULTADOS: A análise espacial, a partir do estimador de intensidade de Kernel, permitiu a construção de mapas de densidade mostrando a Mata Norte como a região onde se concentra o maior número de crianças parasitadas e as populações mais intensamente infectadas pelo Schistosoma mansoni. Com relação aos geohelmintos, há uma maior distribuição espacial dos casos de Ascaris lumbricoides e Trichuris trichiura na Mata Sul, destacando a maior ocorrência de ancilostomídeos entre as Matas Norte e Centro de Pernambuco. CONCLUSÕES: Apesar dos inquéritos e dos vários estudos mostrando a ocorrência de esquistossomose e geohelmintoses na ZMP ainda se desconhecem medidas preventivas que tenham sido implementadas na área endêmica mostrando efetividade na redução destes agravos.

Análise espacial dos casos humanos de esquistossomose em uma comunidade horticultora da Zona da Mata de Pernambuco, Brasil / Spatial analysis of schistosomiasis human cases in the horticultural community of Zona da Mata of Pernambuco state, Brazil

O objetivo deste trabalho foi descrever a distribuição espacial da esquistossomose na comunidade horticultora de Natuba, Vitória de Santo Antão, Pernambuco. Foi conduzido um inquérito parasitológico, onde foi examinado o material fecal de 310 moradores da comunidade. Os casos positivos para Schistosoma mansoni foram georreferenciados e incluídos no croqui da localidade, gerando os mapas de distribuição espacial com estimadores de kernel. Os resultados apresentaram uma alta prevalência para esquistossomose, com 28,4% da população parasitada. Outros parasitos foram encontrados em 25,8% da população. O uso das ferramentas de geoprocessamento permitiu mapear e compreender a distribuição dos casos de esquistossomose no espaço ocupado pela comunidade, destacando e relacionando locais de menor altitude (passíveis de alagamento), com uma maior frequência de casos humanos. Estudos como este fornecem informações para que os serviços de saúde local possam intervir e promover mudanças para que indivíduos residentes em áreas com baixas condições habitacionais minimizem sua exposição ao risco de contrair a esquistossomose.

The objective of this study was to describe the spatial distribution of schistosomiasis in horticultural community of Natuba, district of Vitória de Santo Antão, Pernambuco state. It was conducted a parasitological survey, examined the fecal material of 310 community residents. The cases positive for Schistosoma mansoni were geocoded and included in the computerized template of the community, generating maps of spatial distribution with kernel estimators. The results showed a high prevalence of schistosomiasis, with 28.4% of the parasites. Other parasites were found in 25.8% of the population. The use of GIS tools to map and understand the possible distribution of cases of schistosomiasis in the space occupied by the community highlighting and listing locations of lower elevation (able to flooding), with a higher frequency of human cases. Studies like this provide information to the local health services, may intervene and bring about change for individuals living in areas with low housing conditions to minimize their exposure to risk of contracting schistosomiasis.

The endemisation of schistosomiasis in Porto de Galinhas, Pernambuco, Brazil, 10 years after the first epidemic outbreak

In 2000, after heavy rains and floods in Porto de Galinhas, Pernambuco, Brazil, an outbreak of schistosomiasis was recorded, of which 62.2 percent (412 cases) were of the acute clinical form. Between 2001-2009, occasional findings of Biomphalaria snails parasitised by Schistosoma mansoni indicated that disease transmission was still occurring. This motivated a new epidemiological survey between August-December 2010 to provide an update of the occurrence of this health hazard and to investigate the process of disease endemisation at this locality. This survey gathered parasitological, clinical and malacological data. The results of this survey, compared with data from the year 2000 survey, showed the following: (i) over these 10 years, there were declines in the total percentage of cases and the percentage of acute forms, (ii) the acute clinical form now represents 23.3 percent in contrast with the 62.2 percent detected in 2000 and (iii) the current prevalence of schistosomiasis is 15.7 percent, while in 2000 32.1 percent of the individuals were diagnosed as parasitised. Today, the chronic clinical form represents 76.7 percent of the total number of cases diagnosed, thus showing that over the 10-year period the occurrences of clinical forms became inverted. These findings, together with visual observation of insalubrious environmental conditions, indicate that schistosomiasis has become endemic in Porto de Galinhas.

Schisto Track: um sistema para coleta e monitoramento de inquéritos epidemiológicos conectando sistemas de informações geográficas em tempo real / Schisto Track: a system for gathering and monitoring epidemiological surveys by connecting geographical information systems in real time

A evolução da epidemiologia abrange também instrumentos que são utilizados para a condução de rotinas nos serviços de saúde. Com o desenvolvimento dos recursos tecnológicos aplicáveis à saúde, é possível incorporar nos estudos epidemiológicos plataformas como os sistemas móveis Android para sua adaptação e utilização nos serviços de vigilância epidemiológica e ambiental. A modernização dos processos de coleta de dados, além de diminuir substancialmente o número de erros de transcrição, favorece uma maior velocidade na consolidação dos dados e promove aprimoramento da qualidade de informação gerada. O objetivo deste trabalho é apresentar uma solução para a modernização da condução de inquéritos epidemiológicos em esquistossomose baseado em tecnologia móvel. A aplicação desenvolvida chamada de Schisto Track, é uma ferramenta para captura e análise em tempo real de dados baseados em inquéritos epidemiológicos tradicionais. Para sua implementação foram seguidas as tendências globais no desenvolvimento de instrumentos de coleta de dados, tendo seu arcabouço tecnológico modulado em app nativa e servidor web. A app nativa foi desenvolvida em linguagem Java e otimizada para uso em smartphones e tablets com Android 4.0 ou superior, com sua transmissão de dados feita por rede 3G, via http. O servidor conta com arquitetura backend em linguagem php com banco de dados My SQL. O Frontend foi baseado em linguagem HTML 5, com estruturas de bootstrap e janelas modais atendendo a melhor usabilidade do sistema por parte de técnicos do serviço...

The evolution of epidemiology also includes instruments that are used for improvementroutines in the public health services. With the development of technological resourcesapplicable to health, it is possible to incorporate epidemiological studies on platforms likeAndroid mobile systems for adaptation and utilization in health surveillance services. Themodernization of the processes of data collection, in addition to substantially reduce thenumber of transcription errors, favors a higher speed in data consolidation and consequentimprovement in the quality of information generated. The objective of this work is to presenta solution for the modernization of conducting surveys in schistosomiasis based on mobiletechnology. The developed application called Schisto Track, is a tool for capturing andanalyzing in real-time data based on traditional epidemiological investigations. To implementglobal trends in the development of instruments for data collection were followed, taking theirtechnological framework modulated native app and web server. The native application isoptimized for use on smartphones and tablets with Android 4.0 (or superior) and itstransmission data taken by the 3G network via http. The server architecture includes backendin php language with database My SQL database. The frontend is based on HTML 5 languagewith structures and bootstrap modal windows serving better usability of the system by servicetechnicians...