Trachoma is a contagious bacterial infection that affects the surface of the eyes. Over time, scar tissue or ulcers can form that lead to blindness. Currently around 1.9 million people worldwide are blind or visually impaired by trachoma, and it remains a public health problem in 44 countries. It spreads when bacteria in the secretions from the eyes of an affected individual extend to others either by person-to-person contact or by eye-seeking flies, particularly the Musca sorbens fly. It occurs most commonly in endemic communities with poor hygiene and lack of access to clean water. It is the leading infectious cause of preventable blindness in the world.
What is Trachoma?
Trachoma is a bacterial infection that affects your eyes. It's caused by the bacterium Chlamydia trachomatis. Trachoma is contagious, spreading through contact with the eyes, eyelids, and nose or throat secretions of infected people. It can also be passed on by handling infected items, such as handkerchiefs.
At first, trachoma may cause mild itching and irritation of your eyes and eyelids. Then you may notice swollen eyelids and pus draining from the eyes. Untreated trachoma can lead to blindness.
Causes
Trachoma is caused by certain subtypes of Chlamydia trachomatis, a bacterium that can also cause the sexually transmitted infection chlamydia.
Trachoma spreads through contact with discharge from the eyes or nose of an infected person. Hands, clothing, towels and insects can all be routes for transmission. In developing countries, eye-seeking flies also are a means of transmission.
Risk Factors
Factors that increase your risk of contracting trachoma include:
• Crowded living conditions - People living in close contact are at greater risk of spreading infection.
• Poor sanitation - Poor sanitary conditions, inadequate access to water, and lack of hygiene, such as unclean faces or hands, help spread the disease.
• Age - In areas where the disease is active, it's most common in children ages 4 to 6.
• Sex - In some areas, women's rate of contracting the disease is two to six times higher than that of men. This may be attributed to the fact that women have more contact with children, who are the primary reservoir of infection.
• Flies - People living in areas with problems controlling the fly population may be more susceptible to infection.
Symptoms
Signs and symptoms of trachoma usually affect both eyes and may include:
• Mild itching and irritation of the eyes and eyelids
• Eye discharge containing mucus or pus
• Eyelid swelling
• Light sensitivity (photophobia)
• Eye pain
• Eye redness
• Vision loss
Young children are particularly susceptible to infection. But the disease progresses slowly, and the more painful symptoms may not emerge until adulthood.
Stages
The World Health Organization (WHO) has identified five stages in the development of trachoma:
1. Inflammation — follicular: The early infection has five or more follicles — small bumps that contain lymphocytes, a type of white blood cell — visible with magnification on the inner surface of your upper eyelid (conjunctiva).
2. Inflammation — intense: In this stage, your eye is now highly infectious and becomes irritated, with a thickening or swelling of the upper eyelid.
3. Eyelid scarring: Repeated infections lead to scarring of the inner eyelid. The scars often appear as white lines when examined with magnification. Your eyelid may become distorted and may turn in (entropion).
4. In-turned eyelashes (trichiasis): The scarred inner lining of your eyelid continues to deform, causing your lashes to turn in so that they rub on and scratch the transparent outer surface of your eye (cornea).
5. Corneal clouding (opacity): The cornea becomes affected by an inflammation that is most commonly seen under your upper lid. Continuous inflammation compounded by scratching from the in-turned lashes leads to clouding of the cornea.
Diagnosis
Your doctor can diagnose trachoma through a physical examination or by sending a sample of bacteria from your eyes to a laboratory for testing.
Treatment
Trachoma treatment options depend on the stage of the disease. The treatments available for trachea are :
1. Medications
2. Surgery
Prevention
If you've been treated for trachoma with antibiotics or surgery, reinfection is always a concern. For your protection and for the safety of others, be sure that family members or others you live with are screened and, if necessary, treated for trachoma.
Trachoma can occur worldwide but is more common in Africa, Asia, Latin America, the Middle East and the Pacific Rim. When in regions where trachoma is common, take extra care in practicing good hygiene, which can help prevent infection.
Proper hygiene practices include:
• Face washing and hand-washing - Keeping faces and hands clean may help break the cycle of reinfection.
• Fly control - Reducing fly populations can help eliminate a source of transmission.
• Proper waste management - Properly disposing of animal and human waste can reduce breeding grounds for flies.
• Improved access to water - Having a fresh water source nearby can help improve hygienic conditions.
The WHO Alliance for the Global Elimination of Trachoma by 2020 (GET2020) aims to completely eradicate the disease through implementation of the multifaceted SAFE strategy to prevent and treat trachoma:
• S = surgery to correct in-turned eyelids and trichiasis
• A = antibiotics (azithromycin) to treat active infection
• F = facial cleanliness to reduce human transmission
• E = environmental improvement (such as access to clean water and hygiene measures to reduce the fly population) to reduce human transmission
The antibiotic treatment for active disease is a onetime use of azithromycin (Zithromax) pills. However, reinfection is common if a person doesn't make improvements in hygiene and access to clean water.
When trachoma has progressed to inward-turning of the lashes, surgery is necessary to correct the lid position.
If significant corneal scarring develops, corneal transplantation surgery is required to restore sight.
Various government agencies and international nongovernmental development organizations (INGDOs), such as the Carter Center Trachoma Control Program, work together to implement the SAFE strategy.
Takeaway
• Trachoma is a contagious and potentially blinding infectious eye disease.
• The World Health Organization classified trachoma as one of the neglected tropical diseases and the leading infectious cause of blindness in the world.
• Blindness from trachoma may be preventable by screening and treatment with antibiotics and surgery.
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