Trachoma causes more vision loss and blindness than any other infection in the world. This disease is caused by Chlamydia trachomatis bacteria. Other variants or strains of these bacteria can cause a sexually transmitted infection (chlamydia) and disease in lymph nodes.
This is photomicrograph of a conjunctival smear that revealed the presence of what are known as, intracytoplasmic inclusions Trachoma is easily spread through direct personal contact such as from fingers, through shared towels and clothes, and through flies that have been in contact with the eyes or nose of an infected person. When left untreated, repeated Chlamydia trachomatis infections in the eye can cause severe scarring on the inside of the eyelid. This can cause the eyelashes to scratch the cornea (trichiasis). In addition to causing pain, trichiasis permanently damages the cornea and can lead to irreversible blindness.
Chlamydia trachomatis infections spread in areas that lack access to safely managed drinking water and sanitation systems. Trachoma affects the most resource-limited communities in the world. Globally, almost 1.9 million people have vision loss because of trachoma, and it causes 1.4% of all blindness worldwide.1 In 2021, 136 million people lived in trachoma-endemic areas and were at risk of trachoma blindness.