Prevalence of trachoma in indigenous and non-indigenous areas, Northeastern Brazil, 2019-2021.

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.

Evaluation of real-time PCR assay to detect Schistosoma mansoni infections in a low endemic setting.

BACKGROUND: Schistosomiasis constitutes a major public health problem, and 200 million people are estimated to be infected with schistosomiasis worldwide. In Brazil, schistosomiasis has been reported in 19 states, showing areas of high and medium endemicity and a wide range of areas of low endemicity (ALE). Barra Mansa in Rio de Janeiro state has an estimated prevalence of 1%. ALE represent a new challenge for the helminth control because about 75% of infected individuals are asymptomatic and infections occur with a low parasite load (<100 eggs per gram of feces), causing a decrease in sensitivity of stool parasitological techniques, which are a reference for the laboratory diagnosis of this helminth. The objective of this study was to evaluate the performance of a TaqMan quantitative polymerase chain reaction (qPCR) technique in serum and feces DNA samples using the techniques of Kato-Katz (KK), Hoffman, Pons and Janer (HH) as references, during an epidemiological survey using fecal samples and sera from randomized residents from an ALE. METHODS: A cross-sectional study conducted from April to December 2011 using a probabilistic sampling that collected 572 fecal and serum samples. The laboratory diagnostic techniques used were: KK, HH and qPCR (feces and serum). RESULTS: We obtained the following results using the different diagnostic techniques: KK and HH, 0.9% (n =5); qPCR-feces, 9.6% (n =55); and qPCR-serum, 1.4% (n =8). The qPCR-feces presented the highest positivity, whereas the techniques of HH and KK were the least sensitive to detect infections (0.8%). Compared to HH and KK, qPCR-feces showed a statistically significant difference in positivity (p <0.05), although with poor agreement. CONCLUSION: The positivity rate presented by the qPCR approach was far higher than that obtained by parasitological techniques. The lack of adequate surveillance in ALE of schistosomiasis indicates a high possibility of these areas being actually of medium and high endemicity. This study presents a control perspective, pointing to the possibility of using combined laboratory tools in the diagnosis of schistosomiasis in ALE.

Detection of Internal Transcribed Spacer 1 and hsp70 Genetic Markers Using Restriction Fragment Length Polymorphisms and Sequencing in Identification of Leishmania Species Causing Tegumentary Leishmaniasis in Brazil.

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.

Population Prevalence of Trachoma in Nine Rural Non-Indigenous Evaluation Units of Brazil.

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.

A case-control study to determine the effectiveness of a tetravalent dengue vaccine in the state of Paraná, Brazil.

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.

Geoclimatic, demographic and socioeconomic characteristics related to dengue outbreaks in Southeastern Brazil: an annual spatial and spatiotemporal risk model over a 12-year period.

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.

Vaccine development against neglected tropical diseases. / O desenvolvimento de vacinas contra as doenças tropicais negligenciadas.

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.

Awareness of Chagas disease and socioeconomic characteristics of Bolivian immigrants living in Sao Paulo, Brazil.

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.

Molecular detection of prepatent Schistosoma mansoni infection in Biomphalaria glabrata snail vectors.

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.

Prevalence of trachoma in indigenous and non-indigenous areas, Northeastern Brazil, 2019–2021 / Prevalencia del tracoma en zonas de población indígena y no indígena del nordeste de Brasil, 2019-2021 / Prevalência de tracoma em áreas indígenas e não indígenas, Nordeste do Brasil, 2019-2021

[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.

Prevalence of trachoma in indigenous and non-indigenous areas, Northeastern Brazil, 2019-2021 / Prevalencia del tracoma en zonas de población indígena y no indígena del nordeste de Brasil, 2019-2021 / Prevalência de tracoma em áreas indígenas e não indígenas, Nordeste do Brasil, 2019-2021

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.

Fake news and covid-19: a concern due to the low vaccine coverage in Brazil / Fake News e covid-19: uma preocupação devido à baixa cobertura de vacinação no Brasil

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.

[Database linkage for surveillance of the influenza A(H1N1)pdm09 pandemic in Brazil, 2009-2010]. / Relacionamento entre bases de dados para vigilância da pandemia de influenza A(H1N1)pdm09, Brasil, 2009-2010.

Based on database linkage, the objective of this study was to describe the epidemiological profile of notified cases and deaths from the new viral subtype of influenza during the influenza pandemic. Secondary data were used from the SINAN (Information System for Notifiable Diseases) and SIM (Mortality Information System) for the years 2009 and 2010. Linkage identified 5,973 deaths of cases notified as pandemic influenza. Of these, 2,170 (36.33%) had been classified in the SINAN as confirmed pandemic influenza, 215 (3.6%) as due to other infectious agents, and 3,340 (55.92%) as ruled out. After linkage, some cases in the SINAN database that were closed as death from influenza (n = 658) or death from other causes (n = 847) could not be located in the SIM database. Database linkage can improve the surveillance system and monitoring of morbidity and mortality. We recommend strengthening influenza surveillance in Brazil using linkage of Ministry of Health databases.

A DESCRIPTIVE STUDY OF PANDEMIC INFLUENZA A(H1N1)PDM09 IN BRAZIL, 2009 - 2010.

Influenza A viruses undergo frequent antigenic mutations and may thus cause seasonal epidemics and pandemics. The aim of this study was to recover the epidemiological history of the pandemic influenza A(H1N1)pdm09 in Brazil. A descriptive study was conducted in 2009-2010. The Brazilian Information System for reportable diseases (SINAN) was the data source. A total of 105,054 suspected cases of influenza A(H1N1)pdm09 were reported to SINAN. Of these, 53,797 (51.2%) were classified as the new influenza virus subtype. Among the confirmed cases, 56.7% were female, the mean age was 26.31 (SD ± 18.1) years. Fever was the most common sign among the confirmed cases (99.7%) and the presence of comorbidities was reported in 32.5% of cases. In 2009 there were confirmed cases in all 26 Brazilian States and the Federal District. The incidence (per 100,000 inhabitants) of severe influenza in the population was 28.0 in 2009 and 0.5 in 2010. The states of Paraná (301.3), Santa Catarina (36.0) and Rio Grande do Sul (27.4) presented the highest incidence; 46.4% of the confirmed cases were hospitalized and 47,643 were cured (93.8%). The case-fatality rate was 3.9% in 2009. The pandemic virus A(H1N1)pdm09 hit Brazil between April/2009 and December/2010 with an important difference in the geographic pattern distribution of the cases from the northeast to the south of the country. Children and young adults were the most affected. The limitations of the study were data quality and inconsistencies in the final classification of cases in SINAN. This study highlights the urgent need for improvements in the surveillance of emerging diseases in Brazil.

Classification of transmission risk of vaccine-preventable diseases based on vaccination indicators in Brazilian municipalities. / Classificação de risco de transmissão de doenças imunopreveníveis a partir de indicadores de coberturas vacinais nos municípios brasileiros.

OBJECTIVE: to describe the transmission risk classification of vaccine-preventable diseases in Brazilian municipalities. METHODS: this was a descriptive epidemiologic study using 2014 data of the Brazilian National Immunization Program Information System; the vaccine coverage indicators were used to classify the transmission risk of vaccine-preventable diseases in the municipalities. RESULTS: of the 5,570 Brazilian municipalities, 12.0% were classified as very low risk, 29.6% as low risk, 2.2% as medium risk, 54.3% as high risk and 1.8% as very high risk. CONCLUSION: the vaccination coverage surveillance allowed to identify most of the municipalities in high risk situation and the minority of children living in municipalities with appropriate coverage; the vaccination coverage surveillance using indicators of the Brazilian National Health System (SUS) is a new tool for identifying priority areas where the actions can be more successful for health managers and improve the quality and the success of the immunizations program.

Prevalence of Trachoma in Schoolchildren in Brazil.

PURPOSE: Trachoma was hyperendemic in Brazil until the 20th century. The prevalence has declined sharply in the past decades. The aim of this study was to estimate trachoma prevalence in schoolchildren in Brazilian municipalities with a Human Development Index (HDI) below the national mean. METHODS: A cluster random sampling survey on trachoma prevalence was carried out. Brazilian municipalities with HDI below the national mean, within each of the 27 states, were stratified into three strata according to population size. In each stratum, schools were systematically selected to comprise a sample of 2400 schoolchildren, totaling 7200 per state. In each selected school, children enrolled from 1st to 4th grade were examined for trachoma. The simplified trachoma grading system was used. At a meeting held in each school, the study was explained to parents, and verbal consent sought. RESULTS: A total of 185,862 children were enrolled in the selected schools. Of these, 171,973 (92.5%) participated in the study. The overall prevalence of trachomatous inflammation - follicular was 5.0% (95% confidence interval 4.7-5.3%), varying from 1.5% to 9.0% among the states. Prevalence was significantly associated with the sampling stratum (being higher in small municipalities), the zone in which the school was located (higher in rural schools), and with age (higher among younger children). CONCLUSION: Trachoma is still a public health problem in Brazil, although at a low level of endemicity. As the country advances towards the elimination of blinding trachoma, this survey provides a baseline for evaluation of ongoing and future elimination interventions.

Trachoma in Indigenous Settlements in Brazil, 2000-2008.

PURPOSE: Trachoma, caused by the bacterium Chlamydia trachomatis, is a chronic, recurrent inflammatory disease that affects the cornea and conjunctiva. Trachoma is the leading infectious cause of avoidable blindness worldwide. Its prevalence is higher among individuals of low socioeconomic status, and trachoma is common in indigenous communities. The present study presents aspects of the epidemiological profile of trachoma in indigenous communities in Brazil. METHODS: We analyzed data from two databases collected during trachoma screening activities among the population of indigenous settlements in Brazil between 2000 and 2008. Trachoma cases were detected by ocular examination in accordance with the World Health Organization simplified trachoma grading system. RESULTS: According to the surveillance database, a total of 9582 individuals in six different states were examined. Among children aged 1-9 years, the prevalence of follicular trachomatous inflammation (TF) was 35.2%. In individuals aged ≥15 years, the prevalence of trachomatous trichiasis (TT) was 1.2% in individuals and the sex-specific prevalence was 0.8% in males and 1.6% in females (p = 0.02). In a survey of two states, 2301 indigenous schoolchildren were examined. In the age bracket 5-9 years, the prevalence of TF was 4.9 (95% confidence interval 3.8-6.0%). CONCLUSION: In Brazil, trachoma appears to be a serious public health problem in indigenous settlements, which should therefore be given priority in programs aimed at the elimination of trachoma in the country.

Clinical aspects of influenza A(H1N1)pdm09 cases reported during the pandemic in Brazil, 2009-2010.

OBJECTIVE: To describe the clinical aspects of cases of influenza A(H1N1)pdm09 in Brazil. METHODS: A descriptive study of cases reported in Sistema de Informação de Agravos de Notificação (SINAN), 2009-2010. RESULTS: As the final classification, we obtained 53,797 (56.79%) reported cases confirmed as a new influenza virus subtype, and 40,926 (43.21%) cases discarded. Fever was the most common sign, recorded in 99.74% of the confirmed and 98.92% of the discarded cases. Among the confirmed cases, the presence of comorbidities was reported in 32.53%, and in 38.29% of the discarded cases. The case fatality rate was 4.04%; 3,267 pregnant women were confirmed positive for influenza A new viral subtype and 2,730 of them were cured. The case fatality rate of pregnant women was 6.88%. CONCLUSION: The findings suggested concern of the health system with pregnant women, and patients with comorbidities and quality of care may have favored a lower mortality. We recommend that, when caring for patients with severe respiratory symptoms, with comorbidities, or pregnant women, health professionals should consider the need for hospital care, as these factors make up a worse prognosis of infection by the pandemic influenza virus.