Trachoma
A contagious bacterial eye infection that can cause blindness
Quick Facts
- Type: Bacterial eye infection
- Cause: Chlamydia trachomatis bacteria
- Spread by: Eye and nose secretions; flies
- Importance: Leading infectious cause of blindness worldwide
Overview
Trachoma is a contagious eye infection caused by certain strains of the bacterium Chlamydia trachomatis. It is one of the world's leading infectious causes of blindness and is most common in poor, rural communities with limited access to clean water and sanitation. A single infection usually causes a mild, treatable conjunctivitis, but repeated infections over many years lead to the serious damage that threatens sight.
With repeated episodes, the inside of the upper eyelid becomes scarred and the eyelid can turn inward so that the eyelashes rub against the eye (a stage called trichiasis). This constant rubbing scars the clear front of the eye (the cornea), eventually causing painful vision loss and blindness. Trachoma is preventable and treatable, and global efforts using antibiotics, eyelid surgery, facial cleanliness, and improved sanitation have greatly reduced it in many areas.
Symptoms
Symptoms range from mild irritation in early infection to severe, sight-threatening changes after years of repeated disease.
- Itching and irritation of the eyes and eyelids
- Discharge from the eyes, sometimes with mucus or pus
- Redness and swelling of the eyelids
- Sensitivity to light
- Eye pain and blurred or worsening vision in advanced disease
- Inturned eyelashes that scratch the eye in late stages
Early trachoma is often mild and can be mistaken for ordinary conjunctivitis. The vision-threatening damage develops slowly over years of repeated infection, so children may carry the infection while the most serious effects appear later in adulthood.
Causes
Trachoma is caused by specific strains of Chlamydia trachomatis and spreads through close contact and poor sanitation.
- Direct contact: Contact with eye and nose secretions from an infected person, including through hands.
- Shared items: Sharing towels, clothing, and bedding contaminated with secretions.
- Flies: Certain flies that land on the eyes and face can carry the bacteria between people.
- Crowding and poor hygiene: Conditions that limit handwashing and face washing increase spread.
Risk Factors
- Living in crowded conditions with limited clean water
- Poor sanitation and lack of latrines
- Presence of flies and inadequate face and hand hygiene
- Young age, with repeated infections in childhood
- Living in or visiting areas where trachoma is common
- Close contact with an infected person
Diagnosis
Trachoma is usually diagnosed by examining the eyes and eyelids.
- Eye examination: A clinician looks under the upper eyelid for the follicles, inflammation, scarring, and inturned lashes that define the stages of trachoma, often using a simple grading system.
- History: Living in or traveling to an area where trachoma is common supports the diagnosis.
- Laboratory testing: Swabs can confirm the bacteria when needed, though diagnosis is often clinical, especially in community programs.
Treatment
Treatment depends on the stage and is part of a broader public health strategy known by the acronym SAFE: Surgery, Antibiotics, Facial cleanliness, and Environmental improvement.
- Antibiotics: A single dose of oral azithromycin, or an antibiotic eye ointment, treats active infection. In affected communities, antibiotics may be given to everyone to reduce spread.
- Eyelid surgery: For advanced disease with inturned eyelashes, a procedure to reposition the eyelid protects the cornea and prevents blindness.
- Facial cleanliness: Regular face washing reduces transmission.
- Environmental improvement: Better access to clean water, sanitation, and fly control lowers infection rates.
Early treatment cures the infection, while surgery in late stages can prevent further vision loss.
Prevention
- Wash the face and hands regularly, especially in children
- Improve access to clean water and sanitation
- Control flies and manage waste to reduce breeding sites
- Avoid sharing towels, bedding, and other personal items
- Treat infected individuals and, where recommended, whole communities with antibiotics
When to See a Doctor
See a doctor or eye care provider if you have persistent eye redness, irritation, or discharge, particularly after time in an area where trachoma is common, or if a family member has similar symptoms. Seek prompt eye care if you notice eyelashes turning inward and rubbing the eye, increasing eye pain, light sensitivity, or any change in vision, as these signal advancing disease that can threaten sight and may need surgery to prevent blindness.
Frequently Asked Questions
What causes trachoma?
Trachoma is caused by certain strains of the bacterium Chlamydia trachomatis. It spreads through contact with eye and nose secretions from infected people, shared towels and bedding, and flies that land on the face, especially where clean water and sanitation are limited.
How does trachoma cause blindness?
A single infection is mild, but repeated infections over years scar the inside of the upper eyelid. The eyelid can turn inward so the lashes rub the eye, scarring the cornea. This slow damage causes pain and progressive vision loss that can end in blindness if untreated.
Is trachoma curable?
Yes. Active infection is cured with antibiotics such as a single dose of azithromycin or an antibiotic eye ointment. In advanced cases with inturned eyelashes, eyelid surgery can protect the eye and prevent further vision loss, though existing scarring cannot be reversed.
How can trachoma be prevented?
Regular face and hand washing, access to clean water and sanitation, fly control, and not sharing towels or bedding all reduce spread. Public health programs that treat affected communities with antibiotics and improve the environment have greatly lowered trachoma in many areas.
Can I catch trachoma from someone with red eyes?
Trachoma is contagious and spreads through contact with infected eye and nose secretions, including via hands, shared items, and flies. Good hygiene, not sharing towels, and washing the face and hands reduce the risk. If you have persistent eye symptoms, see a provider for diagnosis and treatment.
References
- World Health Organization (WHO). Trachoma.
- Centers for Disease Control and Prevention (CDC). Trachoma.
- Mayo Clinic. Trachoma — Symptoms and causes.
- MedlinePlus, U.S. National Library of Medicine. Trachoma.