The relationship between prevalence of active trachoma, water availability and its use in a Tanzanian village

This study aimed to establish the relationship between the prevalence of active trachoma in children, water availability and household water use in a village in Tanzania. Nine hundred and fourteen children aged 1-9 years were examined for signs of trachoma. Data were collected on time taken to collect water, amount of water collected and other trachoma risk factors. In a sub-study, 99 randomly selected households were visited twice daily on two consecutive days to document patterns of water use. The prevalence of active trachoma in the children examined was 18.4% (95% CI 15.9-20.9). Active trachoma prevalence increased with increasing water collection time (OR 2.25; 95% CI 1.13-4.46) but was unrelated to the amount of water collected. In the sub-study, active trachoma prevalence was substantially lower in children from households where more water was used for personal hygiene (P for trend < or =0.01), independent of the total amount of water used. The allocation of water to hygiene was predicted by lower water collection time. The key element in the relationship between water availability and trachoma is the allocation of water within households. Collection time may influence both the quantity of water collected and its allocation within the household.     

The ecology of trachoma: an epidemiological study in southern Mexico

A total of 1097 people in two communities in Chiapas, Mexico, were examined for trachoma, and information was obtained about personal and family hygiene. Trachoma was hyperendemic; approximately 25% of those under 10 years old were found to have significant inflammatory trachoma and almost 100% of those aged over 40 years had cicatricial trachoma, although the prevalence of trachoma differed significantly between the two communities. Risk factor analysis was performed by contingency table analysis and χ² testing. The most important parameter associated with the occurrence and severity of inflammatory trachoma in children was the frequency of face washing. Children who washed their faces 7 or more times per week had significantly less trachoma than those who washed less often (χ²_2df = 28.7; P < 0.001). This effect was independent of age, use of clean water and soap, or use of clothes to dry the face. Children who washed infrequently and who used clothes to dry the face or clean the nose were more at risk for trachoma. No parameters of family hygiene or socioeconomic status correlated with the amount of trachoma in a family.     

山东和宁夏6县新农合对妇幼卫生服务的报销制度安排研究

目的:分析研究地区新农合对妇幼卫生服务的报销制度安排。方法:分层随机抽取山东和宁夏6个县,分析当地的新农合方案,并深入访谈相关工作人员。结果:山东和宁夏6个县的新农合服务包都包括了一些妇幼卫生服务,根据纳入服务的不同,分为3种方式,分别为保健方式、医疗方式和综合方式,纳入的服务呈现出重医疗轻保健的状况;新农合妇幼卫生服务的补偿政策呈现出纳入项目增加,报销比例上升,逐步涉及保健项目的变化趋势。结论:预防保健的群体效益和社会效益要远高于个体医疗,随着筹资水平的提高,可以逐步纳入部分保健服务。     

Preliminary evidence that synanthropic flies contribute to the transmission of trachoma- causing Chlamydia trachomatis in Latin America

Synanthropic flies have been shown to be important mechanical vectors of Chlamydia trachomatis, which causes trachoma. However entomological studies have not been forthcoming in Latin America. This study assesses the relationship between household dipteran fly densities and active childhood trachoma in a village on Marajó Island, Pará state, Brazil. For 78 households, members were examined for signs of trachoma, relative abundance of potential trachoma vectors (Diptera, Chloropidae and Diptera, Muscidae) was quantified by trap counts, and additional measures of household hygiene associated with C. trachomatis transmission were assessed. Active childhood trachoma prevalence was 24.1% (45/187), present in 46.2% of sampled households with evidence of case clustering. Childhood prevalence was positively associated with increased fly densities, whereas indirect measures of sanitary conditions (latrine ownership and perceived importance of flies) showed a protective effect. This study indicates that C. trachomatis can be transmitted by synanthropic flies in this region of Latin America.     

Trends in the prevalence of trachoma, South Australia, 1976 to 1990

Abstract: The eye health of rural Aboriginal Australians is known to be poor. Over the past 20 years, Aboriginal communities in remote parts of Australia have had increasing access to eye health services through the National Trachoma and Eye Health Program (NTEHP). Using published and unpublished data, we examined trends in the prevalence of inflammatory trachoma in the Anangu Pitjantjatjara of South Australia. Comparisons using a generalised linear model of surveys in 1976, 1985 and 1990 indicate that there has been a significant reduction in the age-standardised prevalence of inflammatory trachoma in 0- to 20-year-olds. When the 1990 survey was compared with 1976 interim report data from the NTEHP survey, the odds of inflammatory trachoma in 1990 were 0.25 (95 per cent confidence interval (CI) 0.18 to 0.35). When the comparison was with data from the NTEHP survey of the Red Centre, the odds of follicular trachoma in 1990 were 0.51 (CI 0.42 to 0.62), and in comparison with the 1985 NTEHP review data, the odds of inflammatory trachoma in 1990 were 0.28 (CI 0.20 to 0.39). In the older age groups (20 and over), an increase in the prevalence of inflammatory trachoma was found. Although significant, the increase affected a small proportion of the population and may have been because of difficulty in standardising the trachoma grading between surveys, or systematic grading error in the 1990 survey. This study therefore shows that the eye health of Aboriginal people in Central Australia may be improving. The decline in trachoma is welcome and may be caused by improvements in socioeconomic conditions, community development and increasing access to medical care.     

Epidemiology of trachoma in Bebedouro State of S?o Paulo, Brazil: prevalence and risk factors.

Trachoma was considered to have been 'eradicated' from the state of S?o Paulo, Brazil, until 1982 when a number of new cases of trachoma were reported in preschool children in Bebedouro, a small town in northwestern S?o Paulo. A household survey was undertaken to assess the prevalence and epidemiological characteristics of trachoma. A total of 2939 people of all ages was examined having been selected from a two-stage probalilistic household sampling frame based on census data. Overall, 7.2% of the population had evidence of one or more signs of trachoma and 2.1% had inflammatory trachoma. Inflammatory trachoma was more common in children aged one to ten years, especially in the peripheral urban and rural areas, and was more common in boys. The presence of chlamydia was confirmed by direct fluorescent antibody cytology. No cases of blindness due to trachoma were seen. A number of socioeconomic and hygiene variables were studied in order to determine the independent risk factors for trachoma in a household. Variables significantly associated with the occurrence of trachoma in the household were the number of children in the house aged one to ten years, the 'per capita' water consumption, the frequency of garbage collections, source of water, and the educational level of the head of household. Clustering of trachoma in different parts of this community was entirely explained by the concentration of households with these characteristics.     

Rapid assessment for prioritisation of trachoma control at community level in one district of the Kaolack Region, Senegal

The objective of this study was to use a modified Lot Quality Assurance Sampling methodology to classify communities according to prevalence of active trachoma and to estimate the prevalence of trachoma and trichiasis in Nioro department, Kaolack Region, Senegal. A survey was conducted using two-stage cluster sampling to select 50 children aged 2-5 years in each of 33 clusters. In total 1,648 children were examined for active trachoma. Information on trachoma risk factors was collected through interviews with the mother or the household head of the child. Adults (>40 years) with trichiasis were identified through case finding. Nineteen clusters had a low prevalence of active trachoma in children aged 2-5 years (<20%), 11 had medium prevalence (20-40%) and three had high prevalence (>40%). The prevalence of active trachoma in children aged 2-5 years was 17.4% (95% CI 12.9-21.8%). Multivariate-adjusted predictors of active trachoma were: age, facial cleanliness, hygiene practices and keeping cattle in the household. The prevalence of trichiasis in adults aged over 40 years was 1.77% (95% CI 1.24-2.51), equating to 985 adults (95% CI 765-1250) with trichiasis in Nioro department. In conclusion, a survey using rapid methodology showed that trachoma is a problem of public significance in Nioro department, Senegal.     

Risk factors for trachoma in Mali

OBJECTIVES: Prior to commencing a campaign to eliminate blinding trachoma in Mali, a national disease prevalence survey was conducted from March 1996 to June 1997. The prevalence of trachoma was estimated and potential risk factors were studied. METHODS: In each of Mali's seven regions (excluding the capital Bamako), a sample of 30 clusters was taken from the general population, in accordance with the principle of probability proportional to the size of the community. All children under 10 years of age were examined. The simplified clinical coding system proposed by the World Health Organization was used. The position of each village was established and subsequently related to the nearest meteorological station. Socioeconomic and environmental information was collected at both village and household level. The mother or caretaker of each child was questioned about availability and use of water for washing the child. At the time of examination, facial cleanliness and the presence of flies on the face were noted. RESULTS: A total of 15,187 children under 10 years of age were examined. The prevalence of active trachoma (follicular [TF] or intense trachoma [TI]) was 34.9% (95% CI : 32.3-37.6) and the prevalence of TI was 4.2% (95% CI : 3.5-5.0). Aridity/environmental dryness appears to be a risk factor influencing the current geographical distribution of trachoma. Small villages had considerably higher trachoma prevalence than their larger neighbours. The proximity of a medical centre and the existence of social organizations such as a women's association were associated with lower levels of trachoma. Crowded living conditions increased the risk. Using a monetary marker of wealth, we observed a linear inverse relation between wealth and trachoma prevalence. The presence of a dirty face was strongly associated with trachoma (odds ratio [OR] = 3.67) as was the presence of flies on the child's face (OR = 3.62). Trachoma prevalence increased with distance to a water source. Disease prevalence decreased with a higher frequency of both face washing and bathing. CONCLUSIONS: Of all the risk factors examined, facial cleanliness had the strongest association with the prevalence of trachoma. This was followed by the presence of flies on the child's face. Both face washing and bathing showed beneficial effects. Socioeconomic factors such as wealth were significantly explanatory. It is likely that hygiene education and fly control by environmental improvement could have a very significant impact on the prevalence of trachoma in Mali.     

Prevalence and control of trachoma in Australia, 1997-2004

This study aimed to document the prevalence of active trachoma and trichiasis from 1997 to 2003 and from 1987 to 2004, respectively, and to provide an overview of trachoma control activities in Australia in 2004. Prevalence data were obtained from state, territory and regional population health units and unpublished surveys. Information about trachoma control programs and activities currently implemented in Australia was obtained through structured interviews with staff involved in trachoma control. Active trachoma prevalence in Aboriginal and Torres Strait Islander children, ranging from 0-40 per cent, were reported from the Eastern Goldfields, Midwest-Murchison and Kimberley Population Health Units in Western Australia and the Northern Territory's Centre for Disease Control. Large differences in trachoma prevalence were reported within and between different regions and from different years in the same region. Recent surveys of trichiasis in Kimberley and Central Australian Aboriginal and Torres Strait Islander adults demonstrated a prevalence of 9-12 per cent in inland, desert areas. In contrast with developing countries where active trachoma and trichiasis are more common among adult women than men, Australian surveys have identified equal prevalence in both sexes. Interpretation of trachoma prevalence and inter-regional/state/national comparisons were hampered by lack of a uniform method of data collection and analysis. Trachoma control programs were implemented consistently in some communities, and irregularly and/or in piecemeal fashion in others. Trachoma control programs led by regional population health units working in collaboration with primary health care services were more likely to be consistently implemented over long periods of time. Trachoma is a significant public health issue in some Aboriginal communities within Australia. The Communicable Diseases Network Australia has developed guidelines for the public health management of trachoma which provide recommendations on trachoma screening, control and data collection trachoma for affected states and territories.     

Trachoma and water use; a case control study in a Gambian village.

Trachoma is prevalent in many arid areas but data assessing the relationship between water use and trachoma are very scarce. This study compared 18 families having one or more active trachoma cases among the children with 16 trachoma-free families in the same village with respect to water use. Potential confounders such as family size, distance to water source, socio-economic indicators, and hygiene behaviour were assessed in the 2 groups. The families with trachoma were found to use significantly less water per person per day for washing children than did the control group (P = 0.033) with no evidence of confounding by the other measured variables. Low amounts of water for washing were also associated with unclean faces and impetigo in the children. If such a relationship can be substantiated it might provide the basis for effective and cheap interventions against trachoma.     

昭通市实验中学学生沙眼患病情况分析

目的了解昭通市实验中学生沙眼的患病现状,揭示其不良影响,使该校加强对沙眼的防治工作。方法把该校学生筛查沙眼所得的资料录入Excel工作表后进行统计和分析。结果共筛查1 379名学生,诊断为沙眼的学生有102名,患病率为7.40%;初中生沙眼的患病率高于高中生,2者患病率差异有统计学意义(χ2=11.54,P<0.01)。结论昭通市实验中学学生中仍有沙眼流行,校方应高度重视,制订防治策略和措施,控制沙眼在该校的流行和传播。     

闵行区某外来务工人员子女学校学生沙眼患病现况

目的 了解闵行区外来务工人员子女沙眼患病情况及其影响因素,为学生沙眼防治措施提供可靠依据.方法 按世界卫生组织(1987年)诊断标准,对整群随机抽取的闵行区某外来务工人员子女学校703名在校小学生进行沙眼筛查、流行病学调查以及干预治疗.结果 闵行区外来务工人员子女沙眼患病率为9.0％;洗手习惯、洗澡频率、揉眼习惯、有无专用学习桌椅和沙眼史、父亲眼异物感或眼痛、母亲眼异物感、家长或孩子眼睛不适时是否就诊及滴眼药水的态度均与沙眼患病有关(P值均＜0.05).多因素Logistic回归分析显示,勤洗澡是患沙眼的保护因素(OR=0.433),经常用手揉眼睛及父亲近0.5a眼睛有异物感是患沙眼的危险因素(OR值分别为3.150和2.726).结论 外来务工人员子女沙眼患病率较高,纠正学生不良用眼或卫生习惯、转变家长不正确的医疗观念以及及时、规范的治疗是预防与控制沙眼的有效手段.     

How to prevent trachoma and blindness

The etiology associated with the loss of vision due to trachoma has been studied in great detail; so much so, that this cause of human suffering and potential blindness is now considered preventable. This brief communication describes the issues of trachoma prevention, available treatment, cost of prevention, and implementation challenges to establishing a program and making it work. International organizations such as WHO and UNICEF, in collaboration with nongovernmental organizations (NGOs) and local and national governments, have designed a simple yet effective trachoma control program. At the center of the program is community involvement. Better sanitation and access to clean water are two important community issues. Health education from childhood to adulthood is also critical. Individual knowledge about this disease has direct self-care implications (e.g., increased face washing). Treatment consists of antibiotics or simple surgery. Both have been developed to be low-cost and effective. National health officials must determine where health care funds are to be spent. This trachoma control program should be considered cost-effective. Materials and training are available for program implementation. Cost need no longer be the limiting factor in the establishment of a trachoma prevention and control program.     

2010学年上海市浦东和闵行区中小学生常见病情况

目的了解人口输入较大的经济发达区域上海市闵行区内学生常见病现况与浦东区之间差别,为今后开展学生防病工作提供科学依据。方法采用整群抽样方法,对浦东、闵行两区2010学年上报的学生常见病检查资料进行分析。结果两区监测点学校学生视力不良率相比较,差异有统计学意义(χ2=102.93,P0.01);学生贫血率相比较,差异有统计学意义(χ2=27.97,P0.01);沙眼、疑似沙眼检出率相比较,差异均有统计学意义;而蛔虫阳性率、营养不良率、肥胖率相比较,差异均无统计学意义。结论两个区学生的常见病患病率中视力不良和沙眼患病率闵行区较高,而浦东区贫血患病率较高,其他的两区比较接近。两个区的学校均应继续加强健康教育工作,有效预防学生常见病的发生。     

Efficacy of oral azithromycin versus topical tetracycline in mass treatment of endemic trachoma

OBJECTIVE: To compare the impact of mass treatment with oral azithromycin and topical tetracycline on the prevalence of active trachoma. METHODS: A total of 1803 inhabitants from 106 households of eight Gambian villages were randomized, in pairs, to receive either three doses of azithromycin at weekly intervals, or daily topical tetracycline over 6 weeks. Ocular examinations were conducted before treatment, and 2, 6 and 12 months after treatment. FINDINGS: Prior to treatment, 16% of the study participants had active trachoma. Two months after treatment, the prevalence of trachoma was 4.6% and 5.1% in the azithromycin and the tetracycline groups, respectively (adjusted odds ratio (OR) = 1.09; 95% confidence interval (CI) = 0.53, 2.02). Subsequently, the prevalence rose to 16% in the tetracycline group, while remaining at 7.7% in the azithromycin group (adjusted OR at 12 months = 0.52; 95% CI = 0.34, 0.80). At 12 months post-treatment, there were fewer new prevalent cases in the azithromycin group, and trachoma resolution was significantly better for this group (adjusted OR = 2.02; 95% CI = 1.42, 3.50). CONCLUSION: Oral azithromycin therefore appears to offer a means for controlling blinding trachoma. It is easy to administer and higher coverages may be possible than have been achieved hitherto.     

Water availability and trachoma

As part of an epidemiological survey of risk factors for trachoma in 20 villages in the United Republic of Tanzania, we investigated the relationship of village water pumps, distance to water source, and quantity of household water to the risk of inflammatory trachoma. We also evaluated whether there was an association between the cleanliness of children's faces and these water variables. No association was found between the presence of a village water supply and the prevalence of trachoma. However, the risk of trachoma in the household increased with the distance to a water source--although there was no association with the estimated daily amount of water brought into the house. Likewise, children were more likely to have unclean faces if they lived more than 30 minutes from a water source, but whether they had clean faces was not associated with the daily quantity of water brought into the household. The effect of the distance to water supply on trachoma may well reflect the value placed on water within the family, and this determines the priority for its use for hygiene purposes. The results of the study suggest that changing the access to water per se may be insufficient to alter the prevalence of trachoma without also a concomitant effort to change the perception of how water should be utilized in the home.     

Trachoma surveillance in Australia, 2009. A report by the National Trachoma Surveillance and Reporting Unit

Trachoma is highly prevalent in remote Indigenous communities in Australia. The National Trachoma Surveillance and Reporting Unit was established in 2006 as a result of a Federal Government initiative to provide comprehensive surveillance data from regional and remote Indigenous communities considered by the jurisdictional population health staff to be 'At Risk' for endemic trachoma, defined as a trachoma prevalence of 5% or more. This report details the findings from the 2009 trachoma screening program together with trends in trachoma prevalence and screening coverage since 2006. Aboriginal children aged 1-9 years resident in At Risk communities were examined for trachoma using the World Health Organization (WHO) simplified trachoma grading criteria. In the Northern Territory, screening was conducted by staff from the Healthy School Age Kids program and the Aboriginal Community Controlled Health Services. In South Australia, screening was conducted by the Eye Health and Chronic Disease Specialist Support Program and a team of visiting ophthalmologists and optometrists. In Western Australia, screening was conducted by staff from State Government population health units and Aboriginal Community Controlled Health Services. In the Northern Territory, 53 of 86 At Risk communities were screened and data were reported for 2283 children. In South Australia, 12 of 72 At Risk communities were screened and data were reported for 149 children. In Western Australia, 68 of 74 At Risk communities were screened and data were reported for 1684 children. The prevalence of active trachoma ranged from 1%-44% in the Northern Territory, 0%-57% in South Australia and 13%-15% in Western Australia. Trend analysis across all three jurisdictions combined found that neither the prevalence of trachoma nor community screening coverage changed significantly between 2006 and 2009. When trend analysis was "done by jurisdiction, there was a significant decrease in trachoma prevalence and a significant increase in community screening coverage only for Western Australia over the same 4 year period. The implementation of the and Environmental improvement (SAFE) strategy has been variable. Surgery referral processes for trichiasis were reported as available in all screened communities in the Northern Territory and South Australia but only in 35% of screened communities in Western Australia. Antibiotics were distributed according to Communicable Diseases Network Australia guidelines in 89% of communities where treatment was indicated. Facial cleanliness programs and resources were reported as poorly implemented in South Australia and Western Australia while minimal data were reported for environmental conditions in all jurisdictions. No significant change was found in bacterial resistance to azithromycin from 2007 to 2009. Significant gaps remain in community screening coverage and in the full implementation of the SAFE strategy. However, the parallel increase in community screening coverage and decrease in trachoma prevalence in Western Australia suggests that the SAFE strategy might have had an effect in reducing trachoma prevalence in that jurisdiction.     

Reliability of clinical diagnosis in identifying infectious trachoma in a low-prevalence area of Nepal.

The WHO Alliance for Global Elimination of Trachoma by 2020 has increased the need to identify ocular chlamydial infections by clinical examination in areas of both high and low prevalence. The relationship between clinically active trachoma (as defined by clinical examination) and chlamydial infection is known for areas with hyperendemic trachoma, but not for areas with a low prevalence of the clinical disease. In the present study, we examined, photographed, and DNA tested the conjunctivae of children in the Surkhet district of mid-western Nepal, an area known to have a low prevalence of clinically active trachoma. Although 6% of the children aged 10 years and under were found to have clinically active trachoma, none were found to have chlamydia infection by the most sensitive DNA amplification tests available. A very low prevalence of clinically active trachoma is not necessarily evidence of the presence of chlamydial infection. Therefore, the WHO policy of not recommending an intensive trachoma control effort when the prevalence of clinically active trachoma is less than 10% in children is appropriate for this area of Nepal.     

Active trachoma in children aged three to nine years in rural communities in Ethiopia: prevalence, indicators and risk factors

Trachoma is the most important infectious cause of blindness worldwide. In two rural populations in Ethiopia, a programme of preventative and treatment measures was initiated in May 2002. A baseline survey was conducted to evaluate the effect of this programme on the prevalence of active trachoma. A total of 1960 children aged 3-9 years, from 915 households in 40 communities, were examined for the presence of active trachoma. Demographic and household information was collected using questionnaires and household amenities and environmental conditions were observed. Overall, 72% of children had active trachoma. Twenty percent of children aged nine years had trachomatous scarring. In children, discharge in the eyes and flies on the eyes were significant indicators of trachoma (odds ratio [OR] = 3.0, 95% CI 1.94-4.55 and OR = 3.4, 95% CI 2.37-4.88, respectively). Frequency of washing children, a clean environment and hygienic disposal of excrement were significant preventative factors for active trachoma. Prevalence of active trachoma varies widely between and within districts. Risk factors comprise a mix of individual characteristics and household factors. This study demonstrates the need for broad target interventions and a flexible approach to the prevention of trachoma in high prevalence endemic rural populations.     

Trachoma in Chad: results of an epidemiological survey

A regional survey was carried out in Chad in 2000 and 2001 to estimate the prevalence and severity of trachoma. The main objectives were to describe the epidemiological pattern in terms of prevalence of inflammatory trachoma and blinding complications in two sub-samples of the population: children under 10 years of age and women over 14. Two strata were identified based on geographical criteria: two regions [Ouadda?-Biltine, North-East] and [Lac-Kanem-Chari Baguirmi, North-West]. Random samples of thirty clusters were selected in each stratum with probability proportional to size. The simplified grading system proposed by the World Health Organisation (WHO) was used. A total of 3,952 children and 2,492 women were examined. The participation in the survey was 95% for the children sample, 92% for the women sample and the representativity of the samples was fairly good. In children under 10 years of age, the prevalence of follicular trachoma (TF) was estimated at 31.5% (IC(95%): 28.6-34.5) and that of intense inflammatory trachoma (TI) at 16.7% (IC(95%) : 14.4-19.2). The severity of the disease is high, as shown by the prevalence of trichiasis-entropion of 1.5% (IC(95%): 0.9-2.2), of central corneal opacity of 1% (IC(95%) :0.6-1.6) and of trachoma-related blindness of 0.5% (IC(95%) : 0.2-1) in women over 14. The epidemiological pattern of trachoma deserves particular attention in the field of public health in Northern Chad, where all indicators are consistently high. The national program for prevention of blindness has prepared a 3-year work plan to implement the SAFE strategy as soon as possible in these areas.