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.

Using model-based geostatistics for assessing the elimination of trachoma.

BACKGROUND: Trachoma is the commonest infectious cause of blindness worldwide. Efforts are being made to eliminate trachoma as a public health problem globally. However, as prevalence decreases, it becomes more challenging to precisely predict prevalence. We demonstrate how model-based geostatistics (MBG) can be used as a reliable, efficient, and widely applicable tool to assess the elimination status of trachoma. METHODS: We analysed trachoma surveillance data from Brazil, Malawi, and Niger. We developed geostatistical Binomial models to predict trachomatous inflammation-follicular (TF) and trachomatous trichiasis (TT) prevalence. We proposed a general framework to incorporate age and gender in the geostatistical models, whilst accounting for residual spatial and non-spatial variation in prevalence through the use of random effects. We also used predictive probabilities generated by the geostatistical models to quantify the likelihood of having achieved the elimination target in each evaluation unit (EU). RESULTS: TF and TT prevalence varied considerably by country, with Brazil showing the lowest prevalence and Niger the highest. Brazil and Malawi are highly likely to have met the elimination criteria for TF in each EU, but, for some EUs, there was high uncertainty in relation to the elimination of TT according to the model alone. In Niger, the predicted prevalence varied significantly across EUs, with the probability of having achieved the elimination target ranging from values close to 0% to 100%, for both TF and TT. CONCLUSIONS: We demonstrated the wide applicability of MBG for trachoma programmes, using data from different epidemiological settings. Unlike the standard trachoma prevalence survey approach, MBG provides a more statistically rigorous way of quantifying uncertainty around the achievement of elimination prevalence targets, through the use of spatial correlation. In addition to the analysis of existing survey data, MBG also provides an approach to identify areas in which more sampling effort is needed to improve EU classification. We advocate MBG as the new standard method for analysing trachoma survey outputs.

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.

Gender differences in the surgical management of trachomatous trichiasis: an exploratory analysis of global trachoma survey data, 2015-2019.

BACKGROUND: Trachomatous trichiasis (TT) is a painful, potentially blinding eye condition that can be managed through epilation or surgery. Women are affected by TT approximately twice as often as men and are believed to face gendered barriers to receiving surgical care to prevent vision loss. METHODS: We used data from 817 cross-sectional surveys conducted during 2015-2019 in 20 African countries to estimate the prevalence difference (PD) between female and male eyes for four outcomes potentially indicating gender-related differences in TT management: (1) received surgery and developed postoperative TT (PTT), (2) never offered surgery, (3) offered surgery but declined it, and (4) offered epilation but never offered surgery. RESULTS: The prevalence was modestly elevated among female eyes compared with male eyes for having PTT (PD:1.8 [95% confidence limits (CL): 0.6, 3.0]) and having declined surgery for the eye (PD: 6.2 [95% CL: 1.8, 10.7]). The proportion offered epilation was similar by gender (PD:0.5 [95% CL: -0.4, 1.3]), while never having been offered surgery was somewhat more prevalent among male eyes (PD: -2.1 [95% CL: -3.5, -0.7]). CONCLUSIONS: Our results suggest potential gender differences in TT management. More research is needed to determine the causes and implications of the observed differences.

Prevalence of trachoma in Pernambuco State, Brazil (2014-2015).

To estimate the prevalence of cases of trachoma in the population at social risk aged 1-9 years in Pernambuco State and its mesoregions. This was a cross-sectional study in which secondary data from the National Household Survey on Trachoma (2014-2015) were analyzed. The study covered 96 census tracts distributed across the mesoregions of Pernambuco State (Metropolitan Region of Recife, Zona da Mata, Agreste, Sertao do Sao Francisco and Sertao Pernambucano). The study included all homes with children aged 1-9 years, and all of them were examined for trachoma, using the WHO criteria. Among the total of 7,423 children aged 1-9 years who participated in this survey, 446 presented with active trachoma. Thus, the prevalence of trachoma in Pernambuco State, in children between 1-9 years old was 6.65%, and it was higher among children aged 5-9 years (7.12%) and among girls (7.23%). This result was seen in the majority of the mesoregions studied, except in the Zona da Mata and Sertao do Sao Francisco, where there were higher prevalences in the age group of 1-4 years (5.55%) and among boys (5.90%). A tendency towards a higher prevalence between 1 and 6 years of age was observed. The follicular trachoma continues to be an important public health problem in Pernambuco State. It particularly affects poor people, including those living in urban areas of the State.

Household Survey of Trachoma among Children Living in Pernambuco, Brazil.

This study analyzed the association between individual and household factors and the incidence of trachoma among a population aged between 1 and 9 years in the state of Pernambuco. This was a population-based household study conducted using a population-based sample of residents from 96 census sectors of the 1778 sectors considered to be at social risk in the state. The estimated odds ratio of the univariate analysis presented a confidence interval of 95%. Weights and clusters were adjusted through the Generalized Linear and Latent Mixed Model (GLLAM) method. Trachoma cases were the dependent variable in the multivariate analysis. The independent variables were selected through the stepwise forward method, with an input criterion of 20% (p < 0.20) and an output criterion of 10% (p < 0.10). The prevalence was 6.65%. Trachoma was associated with a female sex, age of 5-9 years, either the absence of use or infrequent use of soap to wash the hands and face, the presence of nasal secretion, a lack of piped water from a public supply system, a greater number of rooms used for sleeping, a greater number of people living in the same household, and a family income of up to one minimum monthly wage. The prevalence of follicular trachoma in Pernambuco was higher than what is recommended by the World Health Organization (WHO).

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.

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.

[Prevalence of trachoma in Brazilian schoolchildren]. / Prevalencia de tracoma entre escolares brasileiros.

OBJECTIVE: To estimate the prevalence and describe the distribution of trachoma among schoolchildren in Brazilian municipalities. METHODS: Cross-sectional study, using cluster sampling, of the schoolchildren population of the Brazilian municipalities with Human Development Index - Municipal lower than the national average. This trachoma prevalence survey was conducted by the Ministry of Health, in the period 2002-2007. There were 119,531 schoolchildren selected from 2,270 schools located in 1,156 municipalities. The selected schoolchildren underwent an external ocular examination, with a magnifying glass (2.5X), to detect clinical signs of trachoma according to the WHO criteria. The prevalence of trachoma, by state and national level, and their respective 95% confidence intervals were estimated. Chi-square and Chi-square for trends tests were used to compare categorical variables. RESULTS: There were 6,030 cases of trachoma detected, resulting in a prevalence of 5.0% (95%CI 4.5;5.4). There was no significant difference between the sexes. The prevalence of trachoma was 8.2% among children under 5 years of age, decreasing among higher age groups (p < 0.01). There was a significant difference in prevalence between urban and rural areas, 4.3% versus 6.2% respectively (p < 0.01). Cases were detected in 901 municipalities (77.7% of the sample), in all regions of the country. In 36.8% of the selected municipalities, the prevalence was higher than 5%. CONCLUSIONS: The study shows that trachoma is a significant public health problem in Brazil, contradicting the belief that the disease had been controlled in the country. The survey provides a baseline for evaluating planned interventions aimed at achieving the goal of global certification of elimination of trachoma as a cause of blindness in Brazil by 2020.

Prevalencia de tracoma entre escolares brasileiros / Prevalencia de tracoma entre escolares brasilenos / Prevalence of trachoma in Brazilian schoolchildren

OBJETIVO: Estimar a prevalência e descrever a distribuição do tracoma entre escolares em municípios brasileiros. MÉTODOS: Estudo de corte transversal, usando amostragem por conglomerados, da população escolar dos municípios brasileiros com Índice de Desenvolvimento Humano-Municipal menor que a média nacional. O inquérito de prevalência de tracoma foi realizado pelo Ministério da Saúde entre 2002 e 2007. Foram selecionados 119.531 alunos de 2.270 escolas localizadas em 1.156 municípios. Os alunos foram submetidos ao exame ocular externo, com lupa (2,5X), para detecção de sinais clínicos de tracoma segundo critérios da OMS. Estimou-se a prevalência de tracoma segundo estado e em nível nacional, e seus respectivos intervalos de 95% de confiança. Para a comparação de variáveis categóricas foram usados os testes do Qui-quadrado e do Qui-quadrado de tendência linear. RESULTADOS: Foram detectados 6.030 casos de tracoma, resultando em prevalência de 5,0% (IC95% 4,5;5,4). Não foi encontrada diferença significante entre os sexos. A prevalência de tracoma foi de 8,2% entre menores de cinco anos de idade, diminuindo nas faixas etárias mais altas (p < 0,01). Houve diferença significante entre as prevalências de tracoma na zona urbana e rural, 4,3% versus 6,2%, respectivamente (p < 0,01). Foram detectados casos em 901 municípios (77,7% da amostra), em todas as regiões do País. Em 36,8% dos municípios selecionados a prevalência foi superior a 5%. CONCLUSÕES: O estudo mostra que o tracoma é um importante problema de saúde pública no Brasil, contradizendo a crença de que a endemia estaria controlada no País. O inquérito realizado apresenta uma linha de base para avaliação das intervenções ...

OBJETIVO: Estimar la prevalencia y describir la distribución de tracoma entre escolares en municipios brasileños MÉTODOS: Estudio de corte transversal, usando muestreo por conglomerados, de la población escolar de los municipios brasileños con Índice de Desarrollo Humano-Municipal menor que el promedio nacional. La pesquisa de prevalencia de tracoma fue realizada por el Ministerio de la Salud entre 2002 y 2007. Se seleccionaron 119.531 alumnos de 2.270 escuelas localizadas en 1.156 municipios. Los alumnos fueron sometidos a examen ocular externo, con lupa (2,5X), para detección de señales clínicas de tracoma según criterios de la OMS. Se estimó la prevalencia de tracoma según estado y a nivel nacional, y sus respectivos intervalos de 95% de confianza. Para la comparación de variables categóricas se usaron las pruebas de Chi-cuadrado y de Chi-cuadrado de tendencia linear. RESULTADOS: Se detectaron 6.030 casos de tracoma, resultando en prevalencia de 5,0% (IC95% 4,5;5,4). No se encontró diferencia significativa entre los sexos. La prevalencia de tracoma fue de 8,2% entre menores de cinco años de edad, disminuyendo en los grupos etarios más altos (p0,01). Hubo diferencia significativa entre las prevalencias de tracoma en la zona urbana y rural, 4,3% vs. 6,2%, respectivamente (p0,01). Se detectaron casos en 901 municipios (77,7% de la muestra), en todas las regiones del País. En 36,8% de los municipios seleccionados la prevalencia fue superior a 5%. CONCLUSIONES: El estudio muestra que el tracoma es un importante problema de salud pública en Brasil, contradiciendo la creencia de que la endemia estaría controlada en el País. La pesquisa realizada presenta una línea de base para evaluación de las intervenciones planeadas con miras a alcanzar la meta mundial de certificación de eliminación del tracoma como ...

OBJECTIVE: To estimate the prevalence and describe the distribution of trachoma among schoolchildren in Brazilian municipalities. METHODS: Cross-sectional study, using cluster sampling, of the schoolchildren population of the Brazilian municipalities with Human Development Index - Municipal lower than the national average. This trachoma prevalence survey was conducted by the Ministry of Health, in the period 2002-2007. There were 119,531 schoolchildren selected from 2,270 schools located in 1,156 municipalities. The selected schoolchildren underwent an external ocular examination, with a magnifying glass (2.5X), to detect clinical signs of trachoma according to the WHO criteria. The prevalence of trachoma, by state and national level, and their respective 95% confidence intervals were estimated. Chi-square and Chi-square for trends tests were used to compare categorical variables. RESULTS: There were 6,030 cases of trachoma detected, resulting in a prevalence of 5.0% (95%CI 4.5;5.4). There was no significant difference between the sexes. The prevalence of trachoma was 8.2% among children under 5 years of age, decreasing among higher age groups (p < 0.01). There was a significant difference in prevalence between urban and rural areas, 4.3% versus 6.2% respectively (p < 0.01). Cases were detected in 901 municipalities (77.7% of the sample), in all regions of the country. In 36.8% of the selected municipalities, the prevalence was higher than 5%. CONCLUSIONS: The study shows that trachoma is a significant public health problem in Brazil, contradicting the belief that the disease had been controlled in the country. The survey provides a baseline for evaluating planned interventions aimed at achieving the goal of global certification of elimination of trachoma as a cause of blindness in Brazil by 2020. .

Inquérito domiciliar de prevalência de tracoma em crianças do Distrito Federal, Brasil, julho/2010 / Survey of prevalence trachoma of children in Distrito Federal, Brazil, july/2010

Realizamos um estudo de corte transversal na Vila Estrutural (DF), utilizando amostragem por conglomerados. Os objetivos do estudo foram estimar a prevalência de tracoma em crianças de um a nove anos, descrever o perfil sociodemográfico dos casos e identificar possíveis fatores de risco associados à doença. A medida de associação foi razão de prevalência estimada pela odds ratio e o intervalo de confiança 95% (IC95%). Foram amostradas 766 crianças de 1 a 9 anos e encontrada prevalência de tracoma ativo de 12,5%. A alta prevalência observada reforça que a doença permanece como um problema de saúde pública, sendo necessária a adoção de medidas de controle, com vistas à eliminação da doença, enquanto causa de cegueira. Recomendamos capacitar profissionais da área para detecção e monitoramento de situação epidemiológica e adotar atividades de educação em saúde com enfoque em medidas de controle e prevenção.

We conducted a cross-sectional study in Vila Estrutural (DF) using cluster sampling. This study aimed to estimate prevalence of trachoma in children aged one to nine years, to describe the socio-demographic profile of cases, and to identify possible risk factors associated with the disease. The association measure was prevalence ratio estimated by odds ratio and 95% confidence interval (CI95%). We sampled 766 children aged 1 to 9 years and found a prevalence of active trachoma of 12.5%. The high prevalence reinforces that the disease remains a public health problem, being necessary to adopt control measures, in order to eliminate the disease as a cause of blindness. We recommend enabling professionals to detect and to monitor the epidemiological situation and adopt health education activities focusing on prevention and control measures.