Trachoma (Ancient Greek: "rough eye") is an infectious eye disease, and the leading cause of the world's infectious blindness. Globally, 84 million people suffer from active infection and nearly 8 million people are visually impaired as a result of this disease. Globally this disease results in considerable disability.
Trachoma Symptoms
The bacterium has an incubation period of 5 to 12 days, after which the affected individual experiences symptoms of conjunctivitis, or irritation similar to "pink eye." Blinding endemic trachoma results from multiple episodes of reinfection that maintains the intense inflammation in the conjunctiva. Without reinfection, the inflammation will gradually subside. The Simplified WHO Grading System is summarized below:
• Trachomatous inflammation, follicular (TF) – Five or more follicles of >0.5 mm on the upper tarsal conjunctiva
• Trachomatous inflammation, intense (TI) – Papillary hypertrophy and inflammatory thickening of the upper tarsal conjunctiva obscuring more than half the deep tarsal vessels
• Trachomatous trichiasis (TT) – At least one ingrown eyelash touching the globe, or evidence of epilation (eyelash removal)
• Corneal opacity (CO) – Corneal opacity blurring part of the pupil margin
Further symptoms include:
- Eye discharge
- Swollen eyelids
- Trichiasis (turned-in eyelashes)
- Swelling of lymph nodes in front of the ears
- Corneal scarring
- Further ear, nose and throat complications.
Trachoma Causes
Trachoma is caused by ''Chlamydia trachomatis'' and it is spread by direct contact with eye, nose, and throat secretions from affected individuals, or contact with fomites (inanimate objects), such as towels and/or washcloths, that have had similar contact with these secretions. Flies can also be a route of mechanical transmission. Untreated, repeated trachoma infections result in entropion—a painful form of permanent blindness when the eyelids turn inward, causing the eyelashes to scratch the cornea. Children are the most susceptible to infection due to their tendency to easily get dirty, but the blinding effects or more severe symptoms are often not felt until adulthood.
Blinding endemic trachoma occurs in areas with poor personal and family hygiene. Many factors are indirectly linked to the presence of trachoma including lack of water, absence of latrines or toilets, poverty in general, flies, close proximity to cattle, crowding and so forth. However, the final common pathway seems to be the presence of dirty faces in children that facilitates the frequent exchange of infected ocular discharge from one child’s face to another. Most transmission of trachoma occurs within the family.
Without intervention, trachoma keeps families shackled within a cycle of poverty, as the disease and its long-term effects are passed from one generation to the next.
National governments in collaboration with numerous non-profit organizations implement trachoma control programs using the WHO-recommended SAFE strategy, which includes:
- Surgery to correct advanced stages of the disease;
- Antibiotics to treat active infection, using Zithromax (azithromycin) donated by Pfizer Inc through the International Trachoma Initiative;
- Facial cleanliness to reduce disease transmission;
- Environmental change to increase access to clean water and improved sanitation.
Surgery: For individuals with trichiasis, a bilamellar tarsal rotation procedure is warranted to direct the lashes away from the globe. Early intervention is beneficial as the rate of recurrence is higher in more advanced disease.
Antibiotic therapy: WHO Guidelines recommend that a region should receive community-based, mass antibiotic treatment when the prevalence of active trachoma among one to nine year-old children is greater than 10 percent. Subsequent annual treatment should be administered for three years, at which time the prevalence should be reassessed. Annual treatment should continue until the prevalence drops below five percent. At lower prevalences, antibiotic treatment should be family-based.
Antibiotic selection: (single oral dose of 20 mg/kg) or topical tetracycline (one percent eye ointment twice a day for six weeks). Azithromycin is preferred because it is used as a single oral dose. Although it is expensive, it is generally used as part of the international donation program organized by Pfizer through the International Trachoma Initiative. Azithromycin can be used in children from the age of six months and in pregnancy.
In 1913, President Woodrow Wilson signed an act designating funds for the eradication of the disease. The people that went through Ellis Island had to be checked for trachoma. By the late 1930s, a number of ophthalmologists reported success in treating trachoma with sulfonamide antibiotics. In 1948, Vincent Tabone (who was later to become the President of Malta) was entrusted with the supervision of a campaign in Malta to treat trachoma using sulfonamide tablets and drops.
Although by the 1950s, trachoma had virtually disappeared from the industrialized world, thanks to improved sanitation and overall living conditions, it continues to plague the developing world. This potentially blinding disease remains endemic in the poorest regions of Africa, Asia, and the Middle East and in some parts of Latin America and Australia. Currently, 8 million people are visually impaired as a result of trachoma, and 84 million suffer from active infection.
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article on "Trachoma" All material adapted used from Wikipedia is available under the terms of the GNU Free Documentation License. Wikipedia® itself is a registered trademark of the Wikimedia Foundation, Inc.
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