Trachoma

Definition

Trachoma is a contagious bacterial eye infection that causes chronic conjunctivitis resulting from infection with certain strains of the bacterium “Chlamydia trachomatis”. The distinctive feature of this pathology is that it is characterized by flare-ups interspersed with remissions.

Usually affecting both eyes, trachoma first affects the eyelid, causing irreversible damage to the cornea and leading to loss of vision. Trachoma is the world's leading preventable cause of infectious blindness. According to the World Health Organization (WHO), trachoma is a major public health problem in 42 countries, which is why a global prevention program has been set up to eliminate it by 2030.

Symptoms

The initial symptoms are an accumulation of blood in the conjunctiva, called conjunctival hyperemia, which causes inflammation and redness, swelling of the eyelids, sensitivity to light and tearing.

After years of repeated infections, the progressive appearance of blood vessels in the cornea disrupts vision. In severe cases, the formation of scar tissue inside the eyelid causes the eyelid to turn inwards, rubbing the eyelashes against the eyeball. The result is severe pain and light intolerance. If left untreated, irreversible opacities form, leading to visual impairment and even vision loss. This affects around 5% of trachoma sufferers, particularly those aged between 30 and 40, except in endemic regions where it can occur as early as childhood.

Diagnosis

Diagnosis is usually clinical, based on a doctor's examination of the symptoms and appearance of the eye. If necessary, it can be confirmed by bacteriological sampling.

Prevention

Trachoma is contagious and can be transmitted by simple hand-eye contact or by sharing contaminated objects such as towels, tissues and make-up products. We must therefore take every precaution to avoid these modes of transmission.
Overcrowded homes are particularly susceptible to contamination, since contact between people is close. Sufficient hygiene is therefore essential.
Access to drinking water reduces the risk of reinfection by limiting the spread of infection through regular face and hand washing.
In some parts of the world, flies that have come into contact with the ocular or nasal discharge of an infected person can transmit the infection. It is therefore important to eliminate the places where they breed.

According to the World Health Organization (WHO), trachoma is a major public health problem in 42 countries, which is why a global prevention program exists to eliminate it by 2030.

Treatments

Trachoma is treated with antibiotics, either orally or by ointment. According to the WHO, nearly 65 million people benefited from this treatment in 2021. Antibiotics are highly effective, but do not prevent frequent reinfections. Antibiotics are also generally prescribed as a preventive measure to anyone in contact with trachoma sufferers, since trachoma is highly contagious.

In severe cases, where the eyelid, conjunctiva or cornea are affected, surgery may be required. According to the WHO, nearly 70,000 people underwent such treatment in 2021.

Frequency

According to the WHO, nearly 2 million people worldwide are blind or visually impaired as a result of this condition. This represents 1.4% of all cases of blindness. In addition, some 125 million people live in areas where trachoma is endemic.

People at risk

The disease occurs mainly in children, and particularly in those aged 3 to 6, who form the main reservoir of infection. This is because older children and adults are less likely to contract the disease, due to a more developed immune system and better hygiene.

Does trachoma affect all regions of the world equally?
No, some regions of the world are more affected by trachoma than others. Africa is the continent most affected, and control efforts are most intensive there, but other poor regions in some of the less developed, hot and dry countries of Central and South America, Asia, Australia and the Middle East also record high numbers of cases.

References

content reviewed and controlled on 16.01.2025

Diseases