The Complications And Long Term Effects of Trachoma

Introduction

Trachoma is an eye infection caused by bacteria called Chlamydia trachomatis. It is the most common infectious cause of blindness. Trachoma is transmitted through personal contact (usually with hands, surfaces, bedding,  or clothes) and flies that have been in contact with the eyes or nose of an infected person. 

According to the World Health Organization (WHO), 125 million people live in areas where trachoma is endemic (always present) and are at risk of trachoma blindness. Environmental factors that increase the spread of C. trachomatis include inadequate hygiene, crowded households, and not enough access to water or sanitation.¹

Complications of trachoma

Repeated infections causing scarring of the eyelid

The disease usually starts in early childhood with recurrent C. trachomatis infections of the conjunctiva (the membrane lining the inside of your eyelids and whites of your eyes). Chronic inflammation from the infection, characterised by bumps inside the upper eyelids, is known as active trachoma. 

After repeated infections and inflammation, scar tissue builds up within the conjunctiva that lines the upper eyelids. The immune response, rather than the bacteria themselves, causes this tissue damage.²

Eyelashes turning inwards (trichiasis)

Trachomatous trichiasis is a consequence of the conjunctival scarring discussed earlier. Over 8 million people have trachomatous trichiasis, most of them living in poor rural communities in 57 endemic countries. 

Symptoms of trichiasis include: 

• eyelashes touching the eye 
• pain 
• tearing 
• foreign body sensation (the feeling of something rubbing your eye while blinking) 
• photophobia (sensitivity to light) 

The symptoms are more severe in children and tend to be less severe in older patients. As mentioned above, recurrent C. trachomatis infections and active trachoma most commonly affect young children.³

Corneal scarring and blindness

As the infection progresses, it causes blurred vision and eye pain. Untreated trachoma results in scarring of the eyelid. This can make the eyelashes turn inwards towards the eye (trichiasis). The eyelashes then brush against the cornea (a transparent layer at the front of the eye), scratching it. This continual irritation turns the cornea cloudy. It can also lead to corneal ulcers (open sores in the cornea) and blindness.⁴

Long term effects of trachoma

Impact on economic productivity

One of the long term effects of trachoma is decreased economic productivity due to its complications. The WHO estimated the economic cost of visual impairment and blindness to be $2.9-$5.3 billion per year, or $8 billion including trichiasis.¹

Social stigma and discrimination

The stigma of trichiasis leads to patients being labelled and socially excluded, and community members being unwilling to marry or eat food prepared by them. The underlying reasons for stigmatisation include the appearance of the eyes, the fear of contracting trachoma, being a financial and social burden on the family, and the inability to fulfil a certain gender role.

The social consequences of trichiasis include reduced working opportunities, poor social status, inability to meet religious and social obligations, and problems in relationships. Disease management and educating communities can reduce the stigma related to trachoma, improving patients’ quality of life.⁵

Prevention and treatment of trachoma

Antibiotic treatment

Antibiotic treatment for people infected with C. trachomatis can reduce the risk of reinfection and active trachoma for up to 12 months. Azithromycin is the recommended oral antibiotic, while topical tetracycline can be applied directly. A study found no evidence that azithromycin was less effective than topical tetracycline.⁶

Surgery for trichiasis and corneal scarring

Two types of surgery can be used to treat trichiasis: posterior lamellar tarsal rotation (PLTR) and bilamellar tarsal rotation (BLTR). Studies have shown that PLTR and BLTR are more effective than other surgeries for managing trachomatous trichiasis, and they are recommended by the WHO. The PLTR procedure is the superior strategy because it is easy, safe, and can be done by non-ophthalmologists.⁷

Importance of hygiene and sanitation

Trachoma can be transmitted through contact with the eyes, nose, and hands. The WHO created the SAFE strategy, which aims to eliminate trachoma. 

The SAFE strategy consists of:¹ 

• Surgery to treat the blinding stage (trachomatous trichiasis) 
• Antibiotics to clear infection 
• Facial cleanliness 
• Environmental improvement

The last two components of the strategy relate to long term prevention by promoting facial cleanliness and environmental change, which includes improving access to water and sanitation to control trachoma. The most effective ways to improve hygiene are face washing and having access to a household sanitation facility, typically a simple pit toilet.⁸

Community wide interventions

As mentioned above, the WHO has recommended the SAFE strategy for the elimination of trachoma.¹

The final SAFE strategy for trachoma control is environmental improvement, which can include:⁸

• Public health guidance that places greater emphasis on keeping your face clean 
• Establishing an organisation that focuses on face washing to reduce the transmission of trachoma.
• Providing resources to policy initiatives in countries where trachoma is a problem

Summary

Trachoma, the leading infectious cause of blindness, is an eye infection caused by the bacteria Chlamydia trachomatis. Trachoma is transmitted through contact with the eyes or nose of an infected person, which can occur via contaminated hands, bedding, clothes, hard surfaces, and flies.  

Trachoma often starts in early childhood with recurrent C. trachomatis infections of the conjunctiva lining the inner eyelids. The complications of trachoma include scarring of the eyelid, eyelashes turning inwards (trichiasis), corneal scarring and vision loss, reduced economic productivity, and social stigma and discrimination. 

The WHO established the SAFE strategy to control and prevent trachoma, which includes surgery, antibiotics, facial cleanliness, and environmental improvement by increasing access to water and sanitation facilities.