Trachoma is an eye disease caused by infection with the bacterium Chlamydia trachomatis. WHO describes it as the world’s leading infectious cause of blindness. The long-term damage is linked to repeated infection over time rather than every single episode producing blindness.
How does trachoma spread?
WHO describes direct and indirect transfer of discharge from the eyes or nose of an infected person. Transmission can occur through hands, clothes, bedding and hard surfaces. Certain flies that have contacted eye or nose discharge can also spread infection.
In endemic communities, infection is often acquired while living close to someone with active disease, and WHO identifies the family as the main setting for transmission. A person may clear one episode through the immune response and then acquire the organism again.
Why are young children important in transmission?
Young children are described by WHO as the principal reservoir of infection in endemic areas. Active inflammatory trachoma is common among preschool-aged children in those settings. Infection generally becomes less frequent and shorter in duration with increasing age.
This is population-level information about endemic communities. It does not mean that every episode of eye redness or discharge in a child is trachoma. Many eye conditions can look similar without an examination.
How can repeated infection damage the eye?
After repeated infections over many years, the inside of the eyelid can become scarred. WHO calls this trachomatous conjunctival scarring. The scarred eyelid may turn inward, causing the eyelashes to rub against the surface of the eye. This stage is called trachomatous trichiasis.
The rubbing can cause constant pain, sensitivity to light and damage to the cornea. Without treatment, corneal scarring can lead to visual impairment or blindness. WHO notes that blindness caused by trachoma is difficult to reverse.
Does severe damage occur during childhood?
The timing depends partly on how intensely infection is transmitted. WHO says the damaging stage can occur in childhood in very highly endemic communities, although visual impairment more typically begins between 30 and 40 years of age. This distinction helps explain why childhood infection matters even when the most serious consequences appear later.
Which environmental factors are associated with transmission?
WHO associates more intense transmission with inadequate hygiene, crowded households, inadequate access to water, and inadequate access to and use of sanitation. These are community and living-condition factors; they should not be used to blame an individual child or family.
Trachoma remains a public-health problem in some poor and rural areas of Africa, Central and South America, Asia, Australia and the Middle East. WHO reported that, as of 4 September 2026, 33 countries including India had been validated as having eliminated trachoma as a public-health problem.
What is WHO’s SAFE strategy?
WHO recommends the SAFE strategy for elimination programmes:
- Surgery for the blinding stage, trachomatous trichiasis;
- Antibiotics to clear infection, including mass administration in eligible endemic communities;
- Facial cleanliness; and
- Environmental improvement, particularly better access to water and sanitation.
SAFE is a coordinated public-health strategy. It does not mean that antibiotics or surgery should be selected without an examination and an appropriate programme or clinician.
What does elimination as a public-health problem mean?
WHO validation is based on defined population thresholds and on having a system that can identify and manage new cases of trichiasis. Elimination as a public-health problem therefore does not mean that the bacterium can never be found or that every individual risk has disappeared.
What progress and remaining burden does WHO report?
WHO reported that 92 million people were living in trachoma-endemic areas and at risk of trachoma blindness based on March 2026 data. It also reported that 98,829 people received surgery for the advanced stage in 2025 and that 47.4 million people in endemic communities received antibiotics.
These figures describe the scale of organized elimination programmes. They are not estimates of an individual child’s likelihood of infection. WHO’s global neglected tropical diseases road map uses 2030 as the target for global elimination as a public-health problem.
When should an eye concern be assessed?
A webpage cannot distinguish trachoma from other causes of eye redness, discharge, pain or light sensitivity. Seek assessment from a qualified health professional for persistent eye symptoms, eyelid changes, reduced vision or concern after exposure in an endemic setting. Sudden visual loss, severe eye pain or eye injury requires urgent evaluation.
Why can one cleared infection still matter?
WHO explains that the immune system can clear an individual episode, but reinfection is common in endemic communities. The threat to vision develops through repeated episodes over years, which can progressively scar the inner eyelid. This sequence is why programmes focus on lowering transmission across the community rather than treating only advanced eye damage.
A previous episode does not by itself show that scarring has occurred. Conversely, the absence of severe symptoms during one infection does not describe future community exposure. Examination is needed to assess an individual eye.
How do facial cleanliness, water and sanitation fit together?
Facial cleanliness is one part of the SAFE strategy because eye and nose discharges are involved in transmission. Environmental improvement addresses the conditions that make repeated spread easier, particularly limited access to water and sanitation. WHO also associates crowded households and inadequate hygiene with more intense transmission.
These measures operate at household and community levels. Their inclusion in SAFE shows that eliminating trachoma requires more than one medicine or one clinical procedure. Surgery addresses the advanced blinding stage, antibiotics clear infection, and the cleanliness and environmental components help reduce continued transmission.
References
- World Health Organization. Trachoma, 7 September 2026. Source reviewed 4 October 2026.