Spatial distribution of the positivity of Schistosomiasis mansoni in Maranhao State, Northeastern Brazil, from 2007 to 2016.

Schistosomiasis is considered one of the Neglected Tropical Diseases (NTDs), which affects around 240 million people worldwide. In Brazil, Schistosomiasis mansoni has been registered in 19 states, predominantly in rural areas. This study aimed to analyze the spatial distribution of Schistosomiasis mansoni cases in the Maranhao State from 2007 to 2016, as well as the temporal trend over this period. The data were obtained from secondary sources: Schistosomiasis Control Program of Maranhao (PCE-MA) and Information System for Notifiable Diseases (SINAN). The State Health Regions (HRs) were considered analysis units. Maranhao had a positivity rate of 3.8 for the period. The Regions that presented the highest percentages of positivity in the state were Pinheiro (7.92), Ze Doca (3.30), and Viana (3.10). Municipalities such as Bacuri, Serrano do Maranhao, and Bequimao, located in the Pinheiro HR, showed positivity rates of 16.56, 13.31, and 11.01 respectively. The spatial analysis of schistosomiasis cases showed that Maranhao has two main centers for the spread of the disease, both located in the northern portion of the state, namely the Baixada Maranhense and the east coast. This study concluded that the positivity of Schistosomiasis mansoni in Maranhao was stable over the analyzed period. The state still maintains the Baixada Maranhense micro-region as an important area for the spread of the disease reaching socially vulnerable population groups.

Molluscicidal and cercaricidal activities of the essential oil of Dysphania ambrosioides (L.) Mosyakin & Clemants: Implications for the control of schistosomiasis.

Schistosomiasis is one of the most important tropical diseases. A fundamental strategy to control its spread is the use of natural products against its vectors, which are snails of the genus Biomphalaria. The present study evaluated the chemical composition, the molluscicidal and cercaricidal effects, and the ecotoxicity of the essential oil from the aerial parts of Dysphania ambrosioides (L.) Mosyakin & Clemants (DAEO). The essential oil was obtained by hydrodistillation and analyzed by gas chromatography-mass spectrometry (GC-MS). Molluscicidal and cercaricidal activities were determined by the immersion method. Environmental toxicity was assessed from bioassays using Artemia salina larvae and Danio rerio fish. DAEO presented a 0.8% yield. The GC-MS analysis revealed the predominance of hydrocarbon monoterpenes in the oil. A total of 32 constituents was identified, with α-terpinene (50.69%) being the major compound, followed by p-cymene (13.27%) and ascaridole (10.26%). DAEO was active against adult Biomphalaria glabrata snails and demonstrated lethal effect against Schistosoma mansoni cercariae, with LC50 values of 25.2 (22.7-27.8) and 62.4 (61.8-62.9) µg/mL, respectively. Regarding toxicity to non-target aquatic organisms, the oil showed LC50 values of 86.9 (84.7-87.6) and 18.6 µg/mL (15.5-22.8) for A. salina and D. rerio, respectively. DAEO proved to be a promising natural product for the control of schistosomiasis, acting on both the vectors and the etiological agent of the disease. However, the use of the oil is safer in transmission sites where there are no non-target organisms, as it has showed toxicity to D. rerio fish.

Spatial distribution of the positivity of Schistosomiasis mansoni in Maranhao State, Northeastern Brazil, from 2007 to 2016

ABSTRACT Schistosomiasis is considered one of the Neglected Tropical Diseases (NTDs), which affects around 240 million people worldwide. In Brazil, Schistosomiasis mansoni has been registered in 19 states, predominantly in rural areas. This study aimed to analyze the spatial distribution of Schistosomiasis mansoni cases in the Maranhao State from 2007 to 2016, as well as the temporal trend over this period. The data were obtained from secondary sources: Schistosomiasis Control Program of Maranhao (PCE-MA) and Information System for Notifiable Diseases (SINAN). The State Health Regions (HRs) were considered analysis units. Maranhao had a positivity rate of 3.8 for the period. The Regions that presented the highest percentages of positivity in the state were Pinheiro (7.92), Ze Doca (3.30), and Viana (3.10). Municipalities such as Bacuri, Serrano do Maranhao, and Bequimao, located in the Pinheiro HR, showed positivity rates of 16.56, 13.31, and 11.01 respectively. The spatial analysis of schistosomiasis cases showed that Maranhao has two main centers for the spread of the disease, both located in the northern portion of the state, namely the Baixada Maranhense and the east coast. This study concluded that the positivity of Schistosomiasis mansoni in Maranhao was stable over the analyzed period. The state still maintains the Baixada Maranhense micro-region as an important area for the spread of the disease reaching socially vulnerable population groups.

Community Perceptions on Schistosomiasis in Northeast Brazil.

Schistosomiasis is a serious public health issue in the world infecting more than 200 million people. In Maranhão state, Brazil, the disease has a high prevalence in the Baixada Maranhense microregion, where the socioeconomic conditions, high prevalence of freshwater snails, elevated incidence of human infection, and large rodent populations make the area highly conducive to the life cycle and persistence of schistosomiasis. The objective of this study was to record the perception of residents and health/public education professionals regarding this parasitosis and also understand their knowledge of the relationship between schistosomiasis and the environment. We conducted 53 interviews addressing the socioeconomic, behavioral, and environmental issues surrounding schistosomiasis. It was recorded that the population believed the environment is the main cause of the disease and the fisherman may be stigmatized by their chance of having the disease. Health/public educational professionals in the region indicated that there were no regular educational campaigns, which contributed to the high rates of reinfection and the difficulties in preventing and controlling the spread of the disease. These data clearly demonstrate the need for interdisciplinary work that engages the community in gathering and disseminating knowledge and developing solutions to minimize the occurrence of this major health issue in the region.

Spatial distribution and seasonality of Biomphalaria spp. in São Luís (Maranhão, Brazil).

Two of the three vector species of Schistosoma mansoni Sambon, 1907 in Brazil occur in the state of Maranhão: Biomphalaria glabrata (Say, 1818) and Biomphalaria straminea (Dunker, 1848). For the implementation of effective measures to combat schistosomiasis, it is necessary to identify the spatial and seasonal dynamics of these snails. Therefore, this work brought together information from malacological survey carried out in São Luís (Maranhão, Brazil) to identify the spatial and seasonal distribution patterns of Biomphalaria spp. snails. We used data from malacological surveys of the Municipal Health Secretary of São Luís, conducted between 2006 and 2013 in 23 neighborhoods. We also used data from the mollusk surveys that we conducted for 2 years (2012-2014) in four of these neighborhoods. During the 8-year period (2006-2013), 15,990 specimens of Biomphalaria spp. were collected. There was a positive association between precipitation and the abundance of mollusks of the genus Biomphalaria. During 2012-2014, a total of 2487 snail specimens were obtained (B. glabrata: 1046 specimens; B. straminea: 1426 specimens). There was a positive correlation between precipitation and B. straminea abundance. High density of human occupation and high precipitation are two factors that affect the distribution and density of Biomphalaria spp.

Freshwater gastropods of the Baixada Maranhense Microregion, an endemic area for schistosomiasis in the State of Maranhão, Brazil: I - qualitative study.

INTRODUCTION: The Baixada Maranhense Microregion currently has the highest prevalence of schistosomiasis in the State of Maranhão, likely because this parasitosis is characterized as an occupational disease, and increased contact with water increases the risk of infection by Schistosoma mansoni. This paper reports the results of the first comprehensive freshwater malacological survey performed in the Baixada Maranhense Microregion. METHODS: Freshwater mollusks were collected from the twenty-one municipalities of the Baixada Maranhense Microregion and from Bacurituba and Cajapió and were evaluated for infection by trematodes. RESULTS: A total of 9,129 mollusks were collected (sixteen species), which included the first records of six species in the State of Maranhão: Gundlachia radiata, G. ticaga, Hebetancylus moricandi, Plesiophysa guadeloupensis, Pomacea bridgesii diffusa and Omalonyx sp. Biomphalaria glabrata was found in five municipalities, whereas B. straminea was found in nine. Biomphalaria glabrata and B. straminea were observed in syntopy in Pinheiro and São Bento. Of the 990 specimens of B. glabrata and the 2,109 specimens of B. straminea that were exposed to and/or analyzed for the presence of larval trematodes, only a single specimen of B. glabrata (0.1%) from São Bento shed S. mansoni. Other larval trematodes were first observed in mollusks from the State of Maranhão. CONCLUSIONS: These results indicate that the study area is epidemiologically important due to the presence of two natural vectors of schistosomiasis and the active transmission of schistosomiasis, which was confirmed in the infected specimen that was collected in this study.

Freshwater gastropods of the Baixada Maranhense Microregion, an endemic area for schistosomiasis in the State of Maranhao, Brazil: I - qualitative study

Introduction: The Baixada Maranhense Microregion currently has the highest prevalence of schistosomiasis in the State of Maranhão, likely because this parasitosis is characterized as an occupational disease, and increased contact with water increases the risk of infection by Schistosoma mansoni. This paper reports the results of the first comprehensive freshwater malacological survey performed in the Baixada Maranhense Microregion. Methods: Freshwater mollusks were collected from the twenty-one municipalities of the Baixada Maranhense Microregion and from Bacurituba and Cajapió and were evaluated for infection by trematodes. Results: A total of 9,129 mollusks were collected (sixteen species), which included the first records of six species in the State of Maranhão: Gundlachia radiata, G. ticaga, Hebetancylus moricandi, Plesiophysa guadeloupensis, Pomacea bridgesii diffusa and Omalonyx sp. Biomphalaria glabrata was found in five municipalities, whereas B. straminea was found in nine. Biomphalaria glabrata and B. straminea were observed in syntopy in Pinheiro and São Bento. Of the 990 specimens of B. glabrata and the 2,109 specimens of B. straminea that were exposed to and/or analyzed for the presence of larval trematodes, only a single specimen of B. glabrata (0.1%) from São Bento shed S. mansoni. Other larval trematodes were first observed in mollusks from the State of Maranhão. Conclusions: These results indicate that the study area is epidemiologically important due to the presence of two natural vectors of schistosomiasis and the active transmission of schistosomiasis, which was confirmed in the infected specimen that was collected in this study. .

[Schistosomiasis mansoni in Maranhão State, Brazil, 1997-2003]. / Esquistossomose mansônica no Estado do Maranhão, Brasil, 1997-2003.

The aim of this study was to assess the prevalence of schistosomiasis mansoni in Maranhão State, Brazil, from 1997 to 2003, based on data from the regional health offices included in the Schistosomiasis Control Program. The statistical method was polynomial regression. The municipalities (counties) of Bacabal and São Luís showed a constantly downward trend throughout the time series. Colinas showed an increase in prevalence until 2002, followed by a downward trend. Imperatriz witnessed a constant upward trend. Socioeconomic factors are highly significant for schistosomiasis prevalence in Maranhão, which helps explain the results. The recording of data for the regional health offices is believed to have been affected by changes resulting from decentralization of the Schistosomiasis Control Program. The study's results highlight issues that extend beyond analysis of the pattern of occurrence of schistosomiasis mansoni cases in the State of Maranhão, particularly demonstrating the need for improvements in the population's living conditions.

Esquistossomose mansônica no Estado do Maranhão, Brasil, 1997-2003 / Schistosomiasis mansoni in Maranhão State, Brazil, 1997-2003

O objetivo deste estudo foi analisar a prevalência da esquistossomose mansônica no Maranhão, Brasil, no período de 1997 a 2003, segundo as regionais de saúde contempladas pelo Programa de Controle da Esquistossomose (PCE). O método estatístico utilizado foi a regressão polinomial. Bacabal e São Luís apresentaram tendência decrescente e constante. Colinas demonstrou tendência de incremento até o ano de 2002, com posterior diminuição. Em Imperatriz, observou-se tendência crescente e constante. Concluiu-se que as questões relativas às características socioeconômicas são bastante expressivas no Maranhão e, seguramente, possuem relação com os resultados encontrados. Acredita-se, ainda, que o registro de dados referente às regionais de saúde do estado tenha sido afetado pelas modificações ocorridas por conta da descentralização do PCE. Os resultados deste estudo apontam aspectos que transcendem a análise do padrão de ocorrência de casos de esquistossomose mansônica no Estado do Maranhão, ficando demonstrada, sobretudo, a necessidade de melhorias relacionadas às condições de vida da população.

The aim of this study was to assess the prevalence of schistosomiasis mansoni in Maranhão State, Brazil, from 1997 to 2003, based on data from the regional health offices included in the Schistosomiasis Control Program. The statistical method was polynomial regression. The municipalities (counties) of Bacabal and São Luís showed a constantly downward trend throughout the time series. Colinas showed an increase in prevalence until 2002, followed by a downward trend. Imperatriz witnessed a constant upward trend. Socioeconomic factors are highly significant for schistosomiasis prevalence in Maranhão, which helps explain the results. The recording of data for the regional health offices is believed to have been affected by changes resulting from decentralization of the Schistosomiasis Control Program. The study's results highlight issues that extend beyond analysis of the pattern of occurrence of schistosomiasis mansoni cases in the State of Maranhão, particularly demonstrating the need for improvements in the population's living conditions.

Esquistossomose mansônica no Maranhão: relações com variáveis socioeconômicas e ambientais / Schistosomiasis mansonic in Maranhão: Relations with socioeconomic and environmental factors

No Maranhão, a esquistossomose mansônica constitui-se num relevante problema de origem bastante antiga. Sabe-se que, nesse estado, essa parasitose abrange atualmente 48 dos 217 municípios existentes. Entretanto, a escassez de publicações científicas acerca do comportamento epidemiológico e das características relacionadas à sua transmissão no estado, direciona a permanência do conhecimento insuficiente sobre tais aspectos. Nesse sentido, esta dissertação propôs a realização de dois estudos epidemiológicos sobre a esquistossomose mansônica no estado do Maranhão, Brasil, cujo objetivo consistiu em analisar a tendência de casos da doença e identificar variáveis socioeconômicas e ambientais associadas à transmissão e manutenção da doença nesse estado. Para o primeiro estudo, realizou-se a tendência do percentual de casos positivos de esquistossomose mansônica no Maranhão, entre 1997 e 2003, segundo as regionais de saúde desse estado contempladas com as atividades do exercidas pelo Programa de Controle da Esquistossomose (PCE). O método estatístico empregado foi a regressão polinomial. Posteriormente, realizou-se um estudo ecológico, cujas unidades de análise corresponderam aos 43 municípios do estado do Maranhão com ocorrência de esquistossomose mansônica no período de 2000 a 2003. Os dados da doença foram obtidos no Sistema de Informação do Programa de Controle da Esquistossomose (SISPCE). Foram selecionadas 22 variáveis relacionadas ao contexto socioeconômico e ambiental dos municípios estudados...

In Maranhão, the schistosomiasis constitutes a relevant problem by very ancient origin. It is known that in this state, this parasitic disease currently encompasses 48 of the 217 existing municipalities. However, the scientific publications scarcity on epidemiological and behavioral characteristics related to its transmission in the state, directs the permanence of insufficient knowledge about such aspects. In that sense, this dissertation proposed the holding of two epidemiological studies on schistosomiasis mansoni in Maranhão, Brazil, whose aim was to analyze trends in the cases of the disease and to identify socioeconomic and environmental factors associated with transmission and maintenance of disease. For the first study, the trend in the percentage of positive schistosomiasis cases, between 1997 and 2003, according to the regional state health dealt with the activities performed by the Schistosomiasis Control Program (PCE). The statistical method used was regression. Later, there was an ecological study the units of analysis corresponded to the 43 municipalities related to schistosomiasis occurrence, from 2000 to 2003. Disease data were obtained from the Information System for Schistosomiasis Control Program (SISPCE). We selected 22 variables related to socioeconomic and environmental cities context...