12 November 2008

Eliminating Blinding Trachoma

Trachoma is the leading infectious cause of blindness in the world today. It is also listed as one of the most prevalent neglected tropical diseases. Trachoma is a chronic infection of the eyes. The cause is a non-venereal strain of chlamydia. The disease usually starts in childhood, transmitted from the eye of one person to another by hand contact, flies, or use of contaminated towels or washcloths. Chronic infection results in a characteristic inflammation and enlargement of the follicles inside the upper eyelid (See Photo). With repeated infections, the upper lid becomes scarred, which turns the lashes inward (trichiasis). The resulting irritation and scratching of the cornea produces irreversible damage and eventual blindness.
Trachoma is widespread throughout the world, usually found in impoverished, dry areas, where there is a lack of potable water. Women are more commonly affected than men. Infection rates in some rural communities in Africa can run as high as 40%. The worldwide incidence has dropped from 100 million to 43 million in the past decade, largely due to a UN/WHO sponsored eradication program. However, an estimated three million people are currently blind from this disease.
Treatment is relatively simple, either with tetracycline ointment applied twice daily for 6 weeks, or a single dose of azithromycin, 20mg/kg. In the past, the use of the oral antibiotic was severely limited by its cost. Recently the eradication program was helped by a large donation of azithromycin from its manufacturer, Pfizer. The eradication program works by the so-called SAFE Strategy:
S.= Surgery for trichiasis, the scarred inverted eyelids
A.= Antibiotics, either tetracycline eye ointment or azithromycin.
F.= Facial cleanliness
E.= Environmental Improvement. This includes improving potable water supplies, and reducing fly populations.
The goal for the UN/WHO Program, entitled Alliance for the Global Elimination of Blinding Trachoma by Year 2020, appears to be achievable. We need to be aware of trachoma and its potential to cause blindness, and also to be on the watch for it as we examine children in high-risk areas.

Reference: Cook, J. A. Eliminating Blinding Trachoma. NEJM 2008; 358: 1777.

Submitted by Roger Boe, MD,
UMVIM Medical Consultant

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