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[ABSTRACT]. Objective. To estimate the prevalence of trachoma in indigenous and non-indigenous populations in selected areas of the state of Maranhão, in northeastern Brazil. Methods. This was a population-based survey with probabilistic sampling. For the diagnosis of trachoma, external ocular examination was performed using head magnifying loupes, at 2.5X magnification. The prevalence of trachomatous inflammation – follicular (TF) in children aged 1–9 years and the prevalence of trachomatous trichiasis (TT) in the population aged ≥15 years were estimated. Relative frequencies of sociodemographic and environmental characteristics were obtained. Results. The study included 7 971 individuals, 3 429 from non-indigenous populations and 4 542 from indigenous populations. The prevalence of TF in non-indigenous and indigenous populations was 0.1% and 2.9%, respectively, and the prevalence of TT among indigenous populations was 0.1%. Conclusions. The prevalence of TF and TT in the two evaluation units in the state of Maranhão were within the limits recommended for the elimination of trachoma as a public health problem. However, the prevalence of TF was higher in the indigenous evaluation unit, indicating a greater vulnerability of this population to the disease. The prevalence of TF of below 5.0% implies a reduction in transmission, which may have resulted from improved socioeconomic conditions and/or the implementation of the World Health Organization SAFE strategy.
[RESUMEN]. Objetivo. Estimar la prevalencia del tracoma en poblaciones indígenas y no indígenas en determinadas zonas del estado de Maranhão, en el nordeste de Brasil. Métodos. Se trató de una encuesta de ámbito poblacional con muestreo probabilístico. Para el diagnóstico del tracoma, se realizó un examen ocular externo con una lupa frontal de 2,5X aumentos. Se estimó la prevalencia de la inflamación tracomatosa folicular (TF) en la población infantil de 1 a 9 años y la prevalencia de la triquiasis tracomatosa (TT) en la población de 15 años o más. Se obtuvieron las frecuencias relativas de las características sociodemográficas y ambientales. Resultados. En el estudio participaron 7 971 personas, 3 429 de poblaciones no indígenas y 4 542 de poblaciones indígenas. La prevalencia de la TF en las poblaciones no indígenas e indígenas fue de 0,1% y 2,9%, respectivamente, en tanto que la de la TT en las poblaciones indígenas fue de 0,1%. Conclusiones. La prevalencia de la TF y la TT en las dos unidades de evaluación del estado de Maranhão estuvo dentro de los límites recomendados para la eliminación del tracoma como problema de salud pública. Sin embargo, la prevalencia de la TF fue mayor en la unidad de evaluación indígena, lo que indica una mayor vulnerabilidad de esta población a la enfermedad. La prevalencia de la TF inferior al 5,0% implica una reducción de la transmisión, que puede haber sido consecuencia tanto de la mejora de las condiciones socioeconómicas como de la aplicación de la estrategia SAFE de la Organización Mundial de la Salud.
[RESUMO]. Objetivo. Estimar a prevalência do tracoma em populações indígenas e não indígenas em áreas selecionadas do estado do Maranhão, na região Nordeste do Brasil. Métodos. Inquérito de base populacional com amostragem probabilística. Para o diagnóstico de tracoma, foi realizado exame ocular externo com o auxílio de lupas binoculares com ampliação de 2,5×. Foram estimadas a prevalência de inflamação tracomatosa folicular (TF) em crianças de 1 a 9 anos de idade e a prevalência de triquíase tracomatosa (TT) na população com idade ≥15 anos. Foram obtidas as frequências relativas das características sociodemográficas e ambientais. Resultados. O estudo incluiu 7 971 indivíduos (3 429 de populações não indígenas e 4 542 de populações indígenas). A prevalência de TF nas populações não indígenas e indígenas foi de 0,1% e 2,9%, respectiva- mente, e a prevalência de TT entre as populações indígenas foi de 0,1%. Conclusões. A prevalência de TF e TT nas duas unidades de avaliação no estado do Maranhão ficou dentro dos limites recomendados para a eliminação do tracoma como problema de saúde pública. No entanto, a prevalência de TF foi maior na unidade de avaliação indígena, indicando uma maior vulnerabilidade dessa população à doença. A prevalência de TF abaixo de 5,0% implica uma redução na transmissão, que pode ter sido resultado de melhores condições socioeconômicas e da implementação da estratégia SAFE da Organização Mundial da Saúde.
Asunto(s)
Tracoma , Enfermedades Desatendidas , Prevalencia , Encuestas Epidemiológicas , Brasil , Tracoma , Prevalencia , Enfermedades Desatendidas , Encuestas Epidemiológicas , Brasil , Prevalencia , Encuestas EpidemiológicasRESUMEN
Objective: To estimate the prevalence of trachoma in indigenous and non-indigenous populations in selected areas of the state of Maranhão, in northeastern Brazil. Methods: This was a population-based survey with probabilistic sampling. For the diagnosis of trachoma, external ocular examination was performed using head magnifying loupes, at 2.5X magnification. The prevalence of trachomatous inflammation - follicular (TF) in children aged 1-9 years and the prevalence of trachomatous trichiasis (TT) in the population aged ≥15 years were estimated. Relative frequencies of sociodemographic and environmental characteristics were obtained. Results: The study included 7 971 individuals, 3 429 from non-indigenous populations and 4 542 from indigenous populations. The prevalence of TF in non-indigenous and indigenous populations was 0.1% and 2.9%, respectively, and the prevalence of TT among indigenous populations was 0.1%. Conclusions: The prevalence of TF and TT in the two evaluation units in the state of Maranhão were within the limits recommended for the elimination of trachoma as a public health problem. However, the prevalence of TF was higher in the indigenous evaluation unit, indicating a greater vulnerability of this population to the disease. The prevalence of TF of below 5.0% implies a reduction in transmission, which may have resulted from improved socioeconomic conditions and/or the implementation of the World Health Organization SAFE strategy.
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The identification of Leishmania species that cause tegumentary leishmaniasis (TL) is important for taxonomic and prognostic purposes. Molecular analysis using different Leishmania genomic targets is the most useful method for identifying Leishmania species. Therefore, we evaluated the performance of ribosomal RNA internal transcribed spacer 1 (ITS1) and heat shock protein (hsp70) genetic markers by polymerase chain reaction (PCR), followed by restriction fragment length polymorphism analysis (RFLP) and sequencing, for identification of Leishmania species. Samples from 84 Brazilian patients were amplified. Internal transcribed spacer 1 PCR followed by RFLP (HaeIII) [ITS1-RFLP (HaeIII)] identified 46.4% (39/84) of the samples as compatible with the Viannia subgenus. Internal transcribed spacer 1 PCR followed by sequencing (ITS1-sequencing) identified Leishmania (Viannia) braziliensis in 91.7% (77/84) of the TL samples, Leishmania (Leishmania) amazonensis in 3.6% (3/84), L. (V.) guyanensis in 2.4% (2/84), and L. (L.) infantum in 1.2% (1/84). One of the samples showed the same proportion of similarity with L. (V.) guyanensis and L. (V.) panamensis. hsp70 nested PCR followed by RFLP (HaeIII) [nested hsp70-RFLP (HaeIII)] identified 91.7% (77/84) of the samples as compatible with L. (V.) braziliensis/L. (V.) naiffi, 3.6% (3/84) with L. (L.) amazonensis, 1.2% (1/84) with L. (L.) infantum, and 3.6% (3/84) with L. (V.) guyanensis. hsp70 PCR followed by sequencing (hsp70-sequencing) identified L. (V.) braziliensis in 91.7% (77/84) of the TL samples, L. (L.) amazonensis in 3.6% (3/84), L. (V.) guyanensis in 3.6% (3/84), and L. (L.) infantum in 1.2% (1/84). Our findings clearly showed that nested hsp70-RFLP (HaeIII) is better than ITS1-RFLP (HaeIII) and that ITS1 or hsp70 PCR followed by sequencing was adequate for identifying Leishmania species. We also found that Leishmania (Viannia) braziliensis is the most common species causing TL in Brazil. Therefore, sequencing multiple target genes such as ITS1 and hsp 70 is more accurate than RFLP for identifying Leishmania species.
Asunto(s)
Leishmania braziliensis , Leishmania , Leishmaniasis Cutánea , Leishmaniasis , Humanos , Leishmania/genética , Polimorfismo de Longitud del Fragmento de Restricción , Brasil/epidemiología , Marcadores Genéticos , Leishmaniasis/diagnóstico , Leishmania braziliensis/genética , Proteínas HSP70 de Choque Térmico/genética , Leishmaniasis Cutánea/epidemiología , Leishmaniasis Cutánea/diagnósticoRESUMEN
ABSTRACT Objective. To estimate the prevalence of trachoma in indigenous and non-indigenous populations in selected areas of the state of Maranhão, in northeastern Brazil. Methods. This was a population-based survey with probabilistic sampling. For the diagnosis of trachoma, external ocular examination was performed using head magnifying loupes, at 2.5X magnification. The prevalence of trachomatous inflammation - follicular (TF) in children aged 1-9 years and the prevalence of trachomatous trichiasis (TT) in the population aged ≥15 years were estimated. Relative frequencies of sociodemographic and environmental characteristics were obtained. Results. The study included 7 971 individuals, 3 429 from non-indigenous populations and 4 542 from indigenous populations. The prevalence of TF in non-indigenous and indigenous populations was 0.1% and 2.9%, respectively, and the prevalence of TT among indigenous populations was 0.1%. Conclusions. The prevalence of TF and TT in the two evaluation units in the state of Maranhão were within the limits recommended for the elimination of trachoma as a public health problem. However, the prevalence of TF was higher in the indigenous evaluation unit, indicating a greater vulnerability of this population to the disease. The prevalence of TF of below 5.0% implies a reduction in transmission, which may have resulted from improved socioeconomic conditions and/or the implementation of the World Health Organization SAFE strategy.
RESUMEN Objetivo. Estimar la prevalencia del tracoma en poblaciones indígenas y no indígenas en determinadas zonas del estado de Maranhão, en el nordeste de Brasil. Métodos. Se trató de una encuesta de ámbito poblacional con muestreo probabilístico. Para el diagnóstico del tracoma, se realizó un examen ocular externo con una lupa frontal de 2,5X aumentos. Se estimó la prevalencia de la inflamación tracomatosa folicular (TF) en la población infantil de 1 a 9 años y la prevalencia de la triquiasis tracomatosa (TT) en la población de 15 años o más. Se obtuvieron las frecuencias relativas de las características sociodemográficas y ambientales. Resultados. En el estudio participaron 7 971 personas, 3 429 de poblaciones no indígenas y 4 542 de poblaciones indígenas. La prevalencia de la TF en las poblaciones no indígenas e indígenas fue de 0,1% y 2,9%, respectivamente, en tanto que la de la TT en las poblaciones indígenas fue de 0,1%. Conclusiones. La prevalencia de la TF y la TT en las dos unidades de evaluación del estado de Maranhão estuvo dentro de los límites recomendados para la eliminación del tracoma como problema de salud pública. Sin embargo, la prevalencia de la TF fue mayor en la unidad de evaluación indígena, lo que indica una mayor vulnerabilidad de esta población a la enfermedad. La prevalencia de la TF inferior al 5,0% implica una reducción de la transmisión, que puede haber sido consecuencia tanto de la mejora de las condiciones socioeconómicas como de la aplicación de la estrategia SAFE de la Organización Mundial de la Salud.
RESUMO Objetivo. Estimar a prevalência do tracoma em populações indígenas e não indígenas em áreas selecionadas do estado do Maranhão, na região Nordeste do Brasil. Métodos. Inquérito de base populacional com amostragem probabilística. Para o diagnóstico de tracoma, foi realizado exame ocular externo com o auxílio de lupas binoculares com ampliação de 2,5×. Foram estimadas a prevalência de inflamação tracomatosa folicular (TF) em crianças de 1 a 9 anos de idade e a prevalência de triquíase tracomatosa (TT) na população com idade ≥15 anos. Foram obtidas as frequências relativas das características sociodemográficas e ambientais. Resultados. O estudo incluiu 7 971 indivíduos (3 429 de populações não indígenas e 4 542 de populações indígenas). A prevalência de TF nas populações não indígenas e indígenas foi de 0,1% e 2,9%, respectivamente, e a prevalência de TT entre as populações indígenas foi de 0,1%. Conclusões. A prevalência de TF e TT nas duas unidades de avaliação no estado do Maranhão ficou dentro dos limites recomendados para a eliminação do tracoma como problema de saúde pública. No entanto, a prevalência de TF foi maior na unidade de avaliação indígena, indicando uma maior vulnerabilidade dessa população à doença. A prevalência de TF abaixo de 5,0% implica uma redução na transmissão, que pode ter sido resultado de melhores condições socioeconômicas e da implementação da estratégia SAFE da Organização Mundial da Saúde.
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PURPOSE: To assess the contemporary prevalence of trachoma in Brazil's non-indigenous population, surveys of those thought to be at greatest risk of disease were conducted. METHODS: Rural census tracts of non-indigenous population from nine mesoregions were selected to compose the survey evaluation units (EUs) by considering previously endemic municipalities at greatest risk of trachoma. In each of the nine EUs, we conducted a population-based prevalence survey. Every resident of selected households aged ≥1 year was examined for trachomatous inflammation - follicular (TF) and trachomatous trichiasis (TT). Additionally, data were collected on household-level access to water, sanitation, hygiene (WASH) and education. RESULTS: A total of 27,962 individuals were examined across nine EUs. The age-adjusted TF prevalence in 1-9-year-olds was <5% in each EU. The age- and gender-adjusted prevalence of TT unknown to the health system in ≥15-year-olds was <0.2% in eight EUs; in one EU, it was 0.22%. The median number of households surveyed per EU with access to an improved drinking water source within a 30-minute roundtrip of the house was 66%. School attendance was >99% of surveyed children. CONCLUSIONS: The prevalence of TF was well below the target for elimination as a public health problem in all EUs. Because EUs surveyed were selected to represent the highest-risk non-indigenous areas of the country, TF prevalence is unlikely to be ≥5% in non-indigenous populations elsewhere. In one EU, the prevalence of TT was above the target threshold for elimination. Further investigation and possibly improvement in TT surgical provision are required in that EU.
Asunto(s)
Tracoma , Triquiasis , Niño , Humanos , Lactante , Tracoma/epidemiología , Prevalencia , Brasil/epidemiología , Estudios Transversales , Salud Pública , Triquiasis/epidemiologíaRESUMEN
Background: The Brazilian state of Paraná conducted a mass vaccination campaign against dengue with the tetravalent attenuated vaccine CYD-TDV. The campaign targeted thirty endemic municipalities. The objective of this study was to assess the effectiveness of CYD-TDV in preventing symptomatic virologically confirmed dengue cases according to specific age groups in five of the municipalities. Methods: A case-control study was carried out in the five most populous municipalities targeted by the vaccination, with a vaccine uptake of 25%. Symptomatic dengue cases were identified by the municipal health departments. The age groups targeted were 15-18 and 19-27 in four municipalities and 9-14 and 28-44 in one municipality. All cases were confirmed by real time reverse transcription quantitative polymerase chain reaction (RT-qPCR). For each case, two controls were selected: a neighbourhood control and a workplace or school/college control, matched by age group. A conditional logistic regression model was used to determine the odds ratio for vaccination and the vaccine effectiveness. Findings: Study participants included 618 RT-qPCR-confirmed dengue cases and 1,236 matched controls (with a non-reactive dengue IgM serologic test). Vaccine effectiveness against dengue due to any serotype was 11·1% (95% CI: -19·0%; 33·6%). Effectiveness against DENV-1 was 33·3% (95% CI: -5·0%; 57·6%) and against DENV-2 was -56·7% (95% CI: -142·2%; -5·0%). No DENV-3 was detected. The vaccine was significantly effective in the prevention of DENV-4 cases (VE = 93·3%; 95% CI: 47·7%; 99·2%). Interpretation: CYD-TDV was effective in the prevention of symptomatic cases due to DENV-4, but not due to any serotype. The low dengue seroprevalence in the target population could possibly be related to these results. Funding: This study was supported through a grant to the Sabin Vaccine Institute from Sanofi-Pasteur. Sanofi-Pasteur had no role in the study design, protocol development, data collection, analysis, or publication of results.
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Abstract This study comprised the application of a survey in São Paulo, Brazil, in 2 different periods of 2020: the beginning of the covid-19 pandemic and the disease's first peak (from March to April, 100 interviews) to the time of stability in case fatality rates (from May to July, 100 interviews); the questionnaire included was composed of 14 multiple-choice questions to evaluate the importance of mass communication channels, including social media, and the level of importance attributed to preventive measures at the beginning of the pandemic. The changes in people's behavior, even in a group with more schooling, which initially considered preventive measures to be very important (91%) but, in the second survey, was reduced to 82%. The reinforcement of preventive measures to reduce cases and deaths by covid-19 in Brazil is urgent, allied to recommendations with clear information on the importance of vaccination to avoid low rates as the current situation of vaccine coverage for preventable diseases.
Resumo Foi conduzida uma pesquisa em São Paulo, no Brasil, em 2 períodos distintos de 2020: sendo o primeiro no início da pandemia do covid-19 com um elevado pico de incidência da doença (de março a abril, foram realizadas 100 entrevistas) até o momento de estabilidade nas taxas de letalidade (de maio a julho, foram realizadas outras 100 entrevistas), composto por 14 questões de múltipla escolha para avaliar a importância dos canais de comunicação em massa (incluindo as redes sociais) e o nível de importância atribuído às medidas preventivas no início da pandemia. As mudanças no comportamento das pessoas, mesmo dentro de um grupo de nível educacional alto, que inicialmente considerava as medidas preventivas muito importantes (91%), apresenta considerável queda na segunda pesquisa realizada (redução para 82%). Há a necessidade urgente de reforço de medidas preventivas para redução de casos e óbitos por covid-19 no Brasil, aliadas a recomendações com informações claras como a importância da vacinação para evitar baixas taxas de cobertura vacinal que se apresentam em outras doenças preveníveis por vacinas.
Asunto(s)
Humanos , Masculino , Femenino , Programas de Inmunización , Comunicación , Modelo Transteórico , COVID-19 , COVID-19/prevención & control , Política de Salud , Medios de Comunicación de MasasRESUMEN
Dengue fever is re-emerging worldwide, however the reasons of this new emergence are not fully understood. Our goal was to report the incidence of dengue in one of the most populous States of Brazil, and to assess the high-risk areas using a spatial and spatio-temporal annual models including geoclimatic, demographic and socioeconomic characteristics. An ecological study with both, a spatial and a temporal component was carried out in Sao Paulo State, Southeastern Brazil, between January 1st, 2007 and December 31st, 2019. Crude and Bayesian empirical rates of dengue cases following by Standardized Incidence Ratios (SIR) were calculated considering the municipalities as the analytical units and using the Integrated Nested Laplace Approximation in a Bayesian context. A total of 2,027,142 cases of dengue were reported during the studied period. The spatial model allocated the municipalities in four groups according to the SIR values: (I) SIR<0.8; (II) SIR 0.8<1.2; (III) SIR 1.2<2.0 and SIR>2.0 identified the municipalities with higher risk for dengue outbreaks. "Hot spots" are shown in the thematic maps. Significant correlations between SIR and two climate variables, two demographic variables and one socioeconomical variable were found. No significant correlations were found in the spatio-temporal model. The incidence of dengue exhibited an inconstant and unpredictable variation every year. The highest rates of dengue are concentrated in geographical clusters with lower surface pressure, rainfall and altitude, but also in municipalities with higher degree of urbanization and better socioeconomic conditions. Nevertheless, annual consolidated variations in climatic features do not influence in the epidemic yearly pattern of dengue in southeastern Brazil.
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Dengue , Teorema de Bayes , Brasil/epidemiología , Dengue/epidemiología , Brotes de Enfermedades , Humanos , Incidencia , Factores SocioeconómicosRESUMEN
Neglected tropical diseases constitute a heterogeneous group of diseases that have as a common characteristic to affect poor and unassisted populations with little vocalization capacity and political power. As a result, they receive little attention from the pharmaceutical industry and academia. The present study aimed to summarize the state of the art regarding vaccine development for three relevant neglected tropical diseases in Brazil: Chagas disease, schistosomiasis (Schistosoma mansoni), and leishmaniasis. To this end, we conducted a narrative review of the scientific literature, including publications that allowed us to outline a current overview on the vaccine development for the three diseases. Vaccines against the three diseases are in different stages of development. Vaccine development projects against American trypanosomiasis have yet to reach the clinical evaluation phase. For schistosomiasis, we have candidates for the vaccine in the advanced phase of clinical evaluation. For leishmaniasis, there are already licensed veterinary vaccines, and product candidates for human vaccine in the intermediate stage of clinical evaluation. The reduced funding for these projects has contributed to slow product development.
As doenças tropicais negligenciadas constituem um grupo heterogêneo de enfermidades que apresentam como característica comum afetarem populações pobres e desassistidas, com pouca capacidade de vocalização e de poder político. Em consequência, recebem pouca atenção da indústria farmacêutica e da academia. O presente estudo teve como propósito resumir o estado da arte quanto ao desenvolvimento de vacinas para três doenças tropicais negligenciadas de relevância no Brasil, a doença de Chagas, a esquistossomose mansoni e as leishmanioses. Para tanto, realizou-se uma revisão narrativa da literatura científica, na qual foram incluídas publicações que permitiram traçar um panorama atual do desenvolvimento de vacinas para as três doenças. Essas vacinas estão em estágios distintos de desenvolvimento. Os projetos de desenvolvimento de vacinas contra a tripanossomíase americana ainda não chegaram à fase clínica de avaliação. Já para a esquistossomose há candidatos à vacina em fase avançada de avaliação clínica. Para as leishmanioses já existem vacinas veterinárias licenciadas e produtos candidatos à vacina humana em etapa intermediária de avaliação clínica. O reduzido financiamento para esses projetos tem contribuído para retardar o desenvolvimento dos produtos.
Las enfermedades tropicales desatendidas constituyen un grupo heterogéneo de enfermedades, que presentan como característica común el hecho de que afectan a poblaciones pobres y desasistidas, con poca capacidad de interlocución y poder político. En consecuencia, reciben poca atención de la industria farmacéutica, así como de la academia. Este estudio tuvo como propósito resumir el estado de la cuestión, respecto al desarrollo de vacunas para tres enfermedades tropicales desatendidas relevantes en Brasil como son: la enfermedad de Chagas, la esquistosomiasis y leishmaniosis. Para ello, se realizó una revisión narrativa de la literatura científica, en la que se incluyeron publicaciones que permitieron trazar un panorama actual del desarrollo de vacunas para las tres enfermedades. Estas vacunas están en estadios distintos de desarrollo. Los proyectos de desarrollo de vacunas contra la tripanosomiasis americana todavía no llegaron a la fase clínica de evaluación. Ya en el caso de la esquistosomiasis hay candidatos a la vacuna en fase avanzada de evaluación clínica. Para las leishmaniosis ya existen vacunas veterinarias licenciadas y productos candidatos a la vacuna humana en etapa intermedia de evaluación clínica. La reducida financiación para esos proyectos ha contribuido al retraso en el desarrollo de los productos.
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Esquistosomiasis , Vacunas , Animales , Brasil , Humanos , Enfermedades Desatendidas/prevención & control , Schistosoma mansoni , Esquistosomiasis/prevención & controlRESUMEN
In this study which is part of a research project on Chagas disease (CD) among Bolivian immigrants in Sao Paulo, we describe socioeconomic characteristics, knowledge of CD and implications for acess to health care. We applied a structured questionnaire to a sample of 472 Bolivian adults (> 18 years) living in Sao Paulo and enrolled at the Barra Funda School Health Center. Participants' median age was 28.5 years, 75.0% were from the Bolivian department of La Paz, and >90% worked in the garment industry. Respondents had lived in Sao Paulo for a median of 5.8 years. Only 169 (35.8%) were familiar with CD, while roughly half (50.4%) had lived in natural materials houses in Bolivia, 225 (47.7%) indicated familiarity with the vector, 23.9% had seen the vector in their homes in Bolivia, and 6.4% reported having been bitten by a triatomine bug. Factors associated with awareness of CD were analyzed by chi square tests, and those with p values <0.25 were included in a multivariable logistic regression model. In the multivariable logistic regression analysis, having a relative with CD (OR=4.3, 95% CI=1.5-12.0), having lived in a house with mud or wood walls (OR=0.4, 95% CI=0.2-0.8), and having heard of the triatomine bug, or vinchuca, (OR=10.0, 95% CI=5.1-19.5) were significantly associated with awareness of CD. This study shows a low familiarity with CD among Bolivian migrants living in Sao Paulo, Brazil. Raising awareness of the disease through specific communication strategies should be an essential component of public health programs to reduce the burden of CD in this and other vulnerable populations.
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Enfermedad de Chagas , Emigrantes e Inmigrantes/estadística & datos numéricos , Conocimientos, Actitudes y Práctica en Salud , Adolescente , Adulto , Bolivia/etnología , Brasil , Estudios Transversales , Femenino , Humanos , Masculino , Factores Socioeconómicos , Encuestas y Cuestionarios , Adulto JovenRESUMEN
Approximately 240 million people worldwide are infected by Schistosoma. In Brazil, one of the main intermediate hosts of this parasite is Biomphalaria glabrata snails. The early detection of larval stages in intermediate hosts is an important challenge to public health, but it also represents an opportunity as a new alternative to indicate earlier natural infections before cercariae differentiation and emergence. In this context, we demonstrated that PCR amplification of a 28S gene fragment from the parasite does demonstrate S. mansoni infection in snails 14 days post infection. This conventional polymerase chain reaction amplified clear bands and was able to detect parasitic infection in the intermediate host B. glabrata under experimental conditions. However, we reinforce that this approach requires deeper investigations and further comparisons to confirm its specificity and sensitivity in earlier time points after miracidia infection. This approach has relevant potential as an effective molecular-based strategy for the monitoring of schistosomiasis transmission.
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Biomphalaria/parasitología , Vectores de Enfermedades , Schistosoma mansoni/genética , Animales , Brasil , ADN de Helmintos/análisis , ADN Ribosómico/análisis , Interacciones Huésped-Parásitos , Reacción en Cadena de la PolimerasaRESUMEN
As doenças tropicais negligenciadas constituem um grupo heterogêneo de enfermidades que apresentam como característica comum afetarem populações pobres e desassistidas, com pouca capacidade de vocalização e de poder político. Em consequência, recebem pouca atenção da indústria farmacêutica e da academia. O presente estudo teve como propósito resumir o estado da arte quanto ao desenvolvimento de vacinas para três doenças tropicais negligenciadas de relevância no Brasil, a doença de Chagas, a esquistossomose mansoni e as leishmanioses. Para tanto, realizou-se uma revisão narrativa da literatura científica, na qual foram incluídas publicações que permitiram traçar um panorama atual do desenvolvimento de vacinas para as três doenças. Essas vacinas estão em estágios distintos de desenvolvimento. Os projetos de desenvolvimento de vacinas contra a tripanossomíase americana ainda não chegaram à fase clínica de avaliação. Já para a esquistossomose há candidatos à vacina em fase avançada de avaliação clínica. Para as leishmanioses já existem vacinas veterinárias licenciadas e produtos candidatos à vacina humana em etapa intermediária de avaliação clínica. O reduzido financiamento para esses projetos tem contribuído para retardar o desenvolvimento dos produtos.
Las enfermedades tropicales desatendidas constituyen un grupo heterogéneo de enfermedades, que presentan como característica común el hecho de que afectan a poblaciones pobres y desasistidas, con poca capacidad de interlocución y poder político. En consecuencia, reciben poca atención de la industria farmacéutica, así como de la academia. Este estudio tuvo como propósito resumir el estado de la cuestión, respecto al desarrollo de vacunas para tres enfermedades tropicales desatendidas relevantes en Brasil como son: la enfermedad de Chagas, la esquistosomiasis y leishmaniosis. Para ello, se realizó una revisión narrativa de la literatura científica, en la que se incluyeron publicaciones que permitieron trazar un panorama actual del desarrollo de vacunas para las tres enfermedades. Estas vacunas están en estadios distintos de desarrollo. Los proyectos de desarrollo de vacunas contra la tripanosomiasis americana todavía no llegaron a la fase clínica de evaluación. Ya en el caso de la esquistosomiasis hay candidatos a la vacuna en fase avanzada de evaluación clínica. Para las leishmaniosis ya existen vacunas veterinarias licenciadas y productos candidatos a la vacuna humana en etapa intermedia de evaluación clínica. La reducida financiación para esos proyectos ha contribuido al retraso en el desarrollo de los productos.
Neglected tropical diseases constitute a heterogeneous group of diseases that have as a common characteristic to affect poor and unassisted populations with little vocalization capacity and political power. As a result, they receive little attention from the pharmaceutical industry and academia. The present study aimed to summarize the state of the art regarding vaccine development for three relevant neglected tropical diseases in Brazil: Chagas disease, schistosomiasis (Schistosoma mansoni), and leishmaniasis. To this end, we conducted a narrative review of the scientific literature, including publications that allowed us to outline a current overview on the vaccine development for the three diseases. Vaccines against the three diseases are in different stages of development. Vaccine development projects against American trypanosomiasis have yet to reach the clinical evaluation phase. For schistosomiasis, we have candidates for the vaccine in the advanced phase of clinical evaluation. For leishmaniasis, there are already licensed veterinary vaccines, and product candidates for human vaccine in the intermediate stage of clinical evaluation. The reduced funding for these projects has contributed to slow product development.