Trichiasis

Abstract: Trachoma is the commonest infectious cause of blindness. Recurrent episodes of infection with serovars A-C of Chlamydia trachomatis cause conjunctival inflammation in children who go on to develop scarring and blindness as adults. It was estimated that in 2002 at least 1.3 million people were blind from trachoma, and currently 40 million people are thought to have active disease and 8.2 million to have trichiasis. The disease is largely found in poor, rural communities in developing countries, particularly in sub-Saharan Africa. The WHO promotes trachoma control through a multifaceted approach involving surgery, mass antibiotic distribution, encouraging facial cleanliness and environmental improvements. This has been associated with significant reductions in the prevalence of active disease over the past 20 years, but there remain a large number of people with trichiasis who are at risk of blindness.

Abstract: OBJECTIVE: We aimed to summarize and map the existing global population-based data on active trachoma and trichiasis. Detailed distribution maps of various infectious diseases have proved a valuable tool in their control. Such maps play an important role in assessing the magnitude of the problem, defining priority areas for control, monitoring changes, and advocacy. Until now, information on trachoma prevalence at within country levels has not been systematically collated, analysed and reported. METHODS: We gathered the last 18 years' worth of reported data on active trachoma in children aged less than 10 years, and the last 25 years of reported trichiasis in adults aged 15 years and over from 139 population-based surveys in 33 countries. We collated these data into one database using the "district" (second administrative level) as the standard unit of reporting. We used Geographical Information Systems as a database and cartographic tool to generate a global map of the prevalence of trachoma and trichiasis. FINDINGS: We obtained data on active trachoma and trichiasis from 18 countries in the WHO African Region, 6 in the Eastern Mediterranean Region, 3 in the South-East Asia Region, 3 in the Western Pacific Region and 2 in the Region of the Americas. In 23 countries suspected of having endemic trachoma no reliable district-level population-based data were available. In China and India, data were limited to a few districts. The data highlighted important regional differences and marked national variations in prevalence of active trachoma and trichiasis. CONCLUSION: This is the first attempt to summarize and map the existing population-based data on active trachoma and trichiasis. The lack of data in many countries remains an important obstacle to trachoma control efforts.

Abstract: BACKGROUND The prevalence of blindness and visual impairment are high in Ethiopia and use of services is limited. Determining the barriers to use of eye care services is critical for planning strategies to prevent blindness. METHODS A population-based survey of the magnitude and causes of blindness and visual impairment in adults 40 years and older in the Gurage Zone, central Ethiopia was conducted. Among those individuals who had binocular or monocular vision <6/18, an interview to assess use of eye care services and reasons for a failure to use such services was undertaken. RESULTS Of 850 adults with visual impairment or blindness, 802 were interviewed. Cataract surgery accounted for the primary service currently needed by the blind, followed by trichiasis surgery; service needs were higher for women than for men. Use of services (27.8% of sample) was associated with being male, binocular vision loss, and blindness. The primary reason for a failure to use eye care services were indirect costs (overall, reported by 40% of respondents) associated with accessing the service. There were significant differences between men and women in the reasons for not using the services and between cataract and trichiasis cases but not when comparing binocular vs. monocular conditions, or patients with visual impairment vs. blindness. CONCLUSION The majority of the causes of visual impairment and blindness are treatable (cataract) or preventable (trachomatous trichiasis). The main barrier for seeking service is related to the indirect medical costs of the service. This suggests that efforts are needed to create mechanisms that 'bridge' communities and eye care facilities. A holistic approach that deals both with the organization of services and the sociocultural factors in communities that affect use is needed. The organization of trichiasis surgery at peripheral health centres and screening programmes which identify and facilitate transport to hospital for cataract patients is one approach. The indirect burden of accessing eye care on the family may be lessened by encouraging patients to have surgery earlier (before they require assistance to reach the hospital), and by improving the efficiency of existing services. Promotion of services must be gender-sensitive, ensuring that specific characteristics of the sociocultural roles of women be considered in order to improve uptake among women. Training and placement of cataract surgeons in rural hospitals would also enhance provision of eye care for the rural population.