Elsevier

The Lancet

Volume 371, Issue 9628, 7–13 June 2008, Pages 1945-1954
The Lancet

Seminar
Trachoma

https://doi.org/10.1016/S0140-6736(08)60836-3Get rights and content

Summary

Trachoma is a keratoconjunctivitis caused by ocular infection with Chlamydia trachomatis. Repeated or persistent episodes lead to increasingly severe inflammation that can progress to scarring of the upper tarsal conjunctiva. Trichiasis develops when scarring distorts the upper eyelid sufficiently to cause one or more lashes to abrade the cornea, scarring it in turn and causing blindness. Active trachoma affects an estimated 84 million people; another 7·6 million have end-stage disease, of which about 1·3 million are blind. Trachoma should stand on the brink of extinction thanks to a 1998 initiative launched by WHO—the Global Elimination of Trachoma by 2020. This programme advocates control of trachoma at the community level with four inter-related population-health initiatives that form the SAFE strategy: surgery for trichiasis, antibiotics for active trachoma, facial cleanliness, and environmental improvement. Evidence supports the effectiveness of this approach, and if current world efforts continue, blinding trachoma will indeed be eliminated by 2020.

Introduction

Trachoma is a disease that should stand on the brink of extinction. This blinding scourge has plagued mankind for as long as recorded history. Ancient medical texts from Egypt, China, Rome, Greece, and Arabia all make reference to trachoma.

Trachoma came to prominence in 18th century Europe, when it spread like wildfire through the slums of the industrial revolution. Brought back by troops returning from the Napoleonic wars in Egypt, the Egyptian ophthalmia as it was known rapidly became a major public-health concern and spawned many of the great ophthalmic institutions of Europe and North America. It was such an important public-health concern in the emerging USA that all immigrants who passed through centres such as Ellis Island were checked for trachoma and sent home if they had signs of the disease.

About 100 years ago, many of today's developed countries had trachoma-control activities. However, although the disease has largely disappeared from the developed world as the standard of living and personal and community hygiene has improved, it is still a major issue in poor regions of many developing countries. The WHO Global Alliance for the Global Elimination of Trachoma—GET 2020—promotes the widespread implementation of the SAFE strategy to combat blinding trachoma. SAFE is an acronym for four inter-related public-health interventions: surgery for trichiasis, antibiotics for active trachoma, facial cleanliness, and environmental improvements to reduce transmission. By reducing the reservoir of infection in communities with effective antimicrobial campaigns and decreasing the potential for transmission of infection with facial-cleanliness campaigns, augmented with environmental-health improvements, we can make trachoma history.

Section snippets

Epidemiology

Poor personal and community hygiene are closely associated with extreme poverty and probably promote the transmission of chlamydial infection that leads to trachoma. WHO regards blinding trachoma to be endemic not only in 56 countries of the world, mainly in Africa and the Middle East, but also in parts of Asia, Latin America, and the western Pacific.1 About 84 million people have active trachoma, another 7·6 million have trichiasis,2 and 1·3 million are blind from trachoma.3 A decade ago, 7

Assessment of burden of disease within a population

Establishing the burden of trachoma within a community is important for determining whether a community needs a population-based trachoma intervention, either to monitor the progress of an existing programme or to prioritise an area for trachoma-control activities. WHO recommends that strategies aimed at disrupting the transmission of infection should be implemented based on the prevalence of trachoma in children aged 1–9 years. Interventions should be community based; individual treatment

Surgery

Corneal opacity develops in around a third of individuals who have untreated trichiasis for over a year.54 Trichiasis itself is a cause of substantial disability and reduced quality of life.55, 56 If active trachoma were to be eliminated today, a generation would still be at risk of trichiasis and unnecessary blindness. For these people, surgical intervention is currently the only effective management, and more research is needed on the best delivery of surgical programmes. WHO recommends the

Conclusion and future directions

Increasing people's standard of living and making necessary environmental improvements are the definitive interventions for active trachoma, attested to by the fact that trachoma has been eliminated from all developed cities in the world. Enhancing access to safe drinking water, adequate waste disposal, and better housing is a constructive objective for community development, irrespective of the effect on trachoma. Furthermore, such measures provide a useful link between GET 2020 (the Alliance

Search strategy and selection criteria

We searched Medline with the term “trachoma”. The search was augmented by the extensive libraries of the authors, WHO publications, and searches of key papers by hand. We included papers written in English. There were no date restrictions.

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