What is Trachoma?

Trachoma is an infection of the eyes caused by a cellular microorganism known as Chlamydia trachomatis. The infection is the world’s leading cause of preventable blindness; according to the World Health Organization (WHO), there are 2.2 million people worldwide suffering from vision problems as a result of chronic trachoma, and 1.2 million of these people are permanently blind. The infection is most prevalent in underdeveloped communities, especially those in rural Africa, Asia, Central America and South America in areas of poor sanitation, crowded living conditions, and limited access to clean water.¹ There are at least 51 countries in which trachoma is considered hyper-endemic, meaning that the infection has a very high incidence in these countries. The International Trachoma Initiative (ITI) estimates that 229 million people around the world are currently infected with trachoma.²

Transmission

Trachoma is caused by subtypes of Chlamydia trachomatis, which can also cause the sexually transmitted infection known as chlamydia.³ However, trachoma is different than the eye infections caused by the spread of genital chlamydia to the eyes.

Trachoma is highly contagious and can be transmitted through contact with fluids from the eyes, nose or throat of an infected individual. The infection can be spread via the hands, clothes, shared towels or blankets, even insects.⁴  The infection is most common in children because children tend to have the poorest hygiene, and they are more likely to spread it to other children or their mothers. Therefore, women are at least two times more likely to contract trachoma than men because of their more frequent contact with infected children.¹

Symptoms

Symptoms are usually not severe in the early stages of trachoma, but worsen as the infection progresses. The initial symptoms of trachoma include mild itching and a discharge of thick pus from the eyes. Symptoms may later develop into light sensitivity, eye pain and blurred vision.³ Trachoma is often a chronic infection: its symptoms may go away temporarily, but return with more severity.

Complications

Trachoma progresses through various stages, starting with slight inflammation and increasing in severity until finally resulting in blindness. A common complication, called trichiasis, results when the eyelid begins to turn inward as a result of years of chronic swelling and scarring. This causes immense pain as the eyelashes continually scratch the surface of the eyeball. The damage done to the cornea by this scratching is what eventually leads to partial or complete blindness.¹

Other common results of untreated trachoma are in the form of eyelid deformities, scarring, and in-grown eyelashes. Trachoma progresses very slowly, so if the infection is contracted in childhood, the most severe symptoms are often not experienced until later in life, between ages 30 and 40.³

Diagnosis and Treatment

A healthcare professional can recognize trachoma using a physical exam or by ordering a bacterial culture of discharge samples from the eyes or nose. The early stages of trachoma can be easily treated with antibiotics. Oftentimes an entire community may require treatment for trachoma if it is considered to be endemic. The problem with treating entire communities is that the appropriate amount of medicine is often unattainable or too expensive. Many people also need surgery (such as eyelid reformation) to prevent further damage to the eyes. It is possible to receive a corneal transplant in order to reverse blindness caused by the infection. However, the transplant is not always successful in actually improving a person’s vision.³ WHO reports that in 2012 up to 47 million people in rural communities were treated for trachoma.¹

Prevention

Chlamydia trachomatis thrives in highly-populated communities with unsanitary and crowded living conditions, poor access to clean water, and a large amount of disease-spreading insects.¹ If you live in, have travelled to, or plan to travel somewhere that these risk factors apply, it is important to practice good hygiene by frequently washing your hands and avoiding touching your face as much as possible. If applicable, it is a good idea to undergo trachoma screening upon returning from an endemic country.³

There is currently no vaccine for trachoma, but the World Health Organization is implementing a plan to eliminate worldwide blinding trachoma by the year 2020. This plan has been named the SAFE strategy. The acronym stands for Surgery, Antibiotics, Facial cleanliness, and Environmental improvements. The strategy includes treating those who are already infected with trachoma by way of surgery or antibiotics, educating people in rural endemic areas about basic sanitation and cleanliness techniques to help prevent the transmission of the infection, and finally, improving the poor living conditions in these areas that facilitate the spread of disease.¹ The number of people living with trachoma has already declined from 314 million in 2011 to 229 million in 2014, and many are hopeful that the WHO will succeed in its elimination of the world’s leading preventable cause of blindness in the near future.²

References

1. “Trachoma.” WHO. World Health Organization, n.d. Web. 24 Feb. 2015.

2. “The World’s Leading Cause of Preventable Blindness.” The World’s Leading Cause of Preventable Blindness. International Trachoma Initiative, n.d. Web. 26 Feb. 2015.

3. “Trachoma.” MayoClinic. N.p., n.d. Web. 26 Feb. 2015.

4. “Trachoma Fact Sheet.” Centers for Disease Control and Prevention. Centers for Disease Control and Prevention, 28 Dec. 2009. Web. 26 Feb. 2015.

Last Updated 26 February 2015.