What Causes Trachoma?
- Trachoma is an eye infection, caused by the bacterium chlamydia trachomatis, that may lead to blindness. It is common in poor, rural areas with water shortages, poor sanitary conditions and crowded homes. Up to 41 million people have active trachoma infection, and 7 million have lost their sight due to chronic trachoma infection. Trachoma is the most common cause of preventable blindness in the world.
Children younger than 5 years old are most commonly infected, with prevalence rates up to 90 percent. The infection spreads easily among children and from children to their mothers. It spreads through contact with discharge from an infected eye by handkerchiefs or tissues, hands or flies. Chronic infection is typical. - A single bout of trachoma infection will not cause blindness. However, repeated infections gradually cause the eyelid to turn in toward the eyeball. The eyelashes irritate the eye, causing severe pain and eventually scarring the cornea, leading to irreversible blindness. Trachoma blindness usually strikes by the time the infected person reaches 40 years of age.
The infection causes pimple-like bumps on the inside surface of the eyelid. Chronic trachoma progresses through five stages, ending in blindness. The infection begins with inflammation of the eyelid tissue and conjunctiva, the outer covering of the eyeball. The inflammation worsens, causing thickening and then scarring of the conjunctiva. In later stages, the eyelashes rub the cornea and, finally, the cornea becomes cloudy, ending in blindness. - Trachoma infection can be treated with antibiotics. Prevention includes clean water sources, improved personal hygiene and clean living conditions.
The World Health Organization launched its Global Elimination of Trachoma initiative, with the goal of global trachoma eradication by 2020. To reach this goal, the initiative is using the SAFE strategy: eyelid surgery, antibiotics for active infection, facial cleanliness and environmental changes (that is, clean water and improved sanitation). In 2006, Morocco became the first country to eradicate trachoma using the SAFE strategy. - Trachoma is an old, global disease. Scrolls from ancient Egypt contain references to trachoma. Although it is now found in 56 countries, it was once prevalent across the world, including rural areas of the United States. The disease is now found in poor, rural areas of Africa, Asia, Australia, the Middle East and Central and South America. Trachoma is eliminated as regions became developed and living conditions improved. In the regions where it still exists, trachoma-related blindness is so common it is almost expected.