What Is Trachoma?
Trachoma is a severe infectious follicular conjunctivitis frequently seen in developing countries. It affects children aged five to ten years, with complications starting from 20 to 30 years. In severe cases, it is known to cause a variety of eyelid malformations by its tendency to produce scarring. It is a major public health problem and deserves attention from the common man in terms of preventive measures to be taken and hygienic practices to be followed and city planners and executives, as sanitation and hygiene are the major factors responsible for this disease.
The World Health Organization (WHO) has created a mission to eliminate trachoma by 2020 through various innovative public health strategies known as S.A.F.E.
-
S- Surgery to correct the advanced, blinding stage of the disease (trichiasis).
-
A- Antibiotics to treat an active infection.
-
F- Facial cleanliness.
-
E- Environmental improvements in water and sanitation to reduce disease transmission.
What Are the Causes of Trachoma?
Trachoma is caused by Chlamydia trachomatis, a bacteria that is gram-negative with a life cycle tailormade to evade our natural immune defense mechanisms. The infective form of this organism called an elementary body, is an inert, tough protective shell harboring the infectious organism. Through this form, chlamydiae are capable of surviving extreme conditions that would generally instantly kill the organism. After gaining entry into our body, the elementary body infects our bodily cells by endocytosis, which coats itself with the cells' own coating and starts multiplying inside. During this whole process, the organisms are protected from our immune protective mechanisms through a variety of countermeasures by the organism. Once inside the cell, the elementary body becomes active, transforms into a reticular body, and starts multiplying within the host cell until the host cell can no longer sustain the multiplication rate of these infectious bodies. The reticular bodies once again transform into elementary bodies before rupturing the host cell, infecting another cell, and continuing the same cycle all over again.
What Are the Stages of Trachoma?
Trachoma comprises of two stages:
The Active Phase:
The active phase shows follicular conjunctivitis as a feature. The diagnosis is completely based on the clinical appearance of active trachoma in a community where trachoma is endemic or suspected to be endemic. Usually, patients with active trachoma are asymptomatic or present with the only symptom of follicular conjunctivitis.
The Scarring (Cicatricial) Phase:
The scarring or cicatricial phase has special clinical features, which lead to definitive diagnosis in most cases. Conjunctival scarring alone can be asymptomatic. However, the tear film's structure changes due to the destruction of mucous and serous glands, often leading to dry eye. Both phases can coexist in the same patient and may not follow a linear pathway of disease pathogenesis.
What are the Symptoms and Signs of Trachoma?
1. In Milder Forms -
a. Follicles - These are the proliferation of lymphoid cells as an immune reaction to the spread of chlamydia. This is the earliest and most characteristic sign. At this stage, the disease can be easily reversed and will not cause any permanent damage to the patient’s eye.
b. Severe Inflammation - The eye becomes red and starts to water. This is also a feature seen in early disease and should raise an alarm that the condition needs to be urgently treated.
2. In Severe Forms -
a. Scarring - In this stage, the inflamed and reactive tissues have been replaced by scar or dead tissues. This indicates a stage of irreversibility, and the tissue, once scarred, does not regain its normal elasticity and function. The scarred tissue is relatively rigid and non-malleable and gives rise to complications of the lid, such as the inward turning of eyelid margins.
b. Trichiasis - In more severe forms of scarring, the inward-turned eyelashes will rub against the cornea, grating it to cause erosions and ulcers. If not treated properly, these ulcers and erosions will lead to the formation of permanent corneal opacification, thus blinding the patient for life. The only cure for such blindness is surgery, and the outcomes of the surgery are not 100 % good; that is, not all patients improve with surgery.
How Can Trachoma Be Treated?
The treatment of trachoma includes the S.A.F.E. strategy developed by the WHO.
Surgical Care:
-
In order to correct trichiasis, eyelid surgery is a must in people with trichiasis who are at a higher risk for trachomatous blindness.
-
Eyelid rotation stops the progression of corneal scarring, and in some cases, it can result in a slight improvement in visual acuity.
Antibiotic Therapy:
The W.H.O. has recommended two antibiotics for trachoma control:
-
Oral Azithromycin (Azithromycin eye drops have also been proved to be effective against the infection. Azithromycin is the drug of choice as it is easy to administer as a single oral dose.Its administration can be observed directly).
-
Tetracycline eye ointment.
Adverse effects, if any, are usually mild such as gastrointestinal upset or rash. The infection usually involves the nasopharynx. Therefore, there are chances of reinfection if only topical antibiotics are used.
Facial Cleanliness:
Various studies and trials have shown that facial cleanliness in children reduces the risk and severity of this infection.For the successful elimination of trachoma, health education and prevention activities must be promoted.
Environmental Improvement:
Improvements in personal and community hygiene are most important to reduce the prevalence and eliminate trachoma. Environmental improvement can be achieved by improving water supplies and household sanitation, including methods for safely disposing of human feces.
Preventive Measures:
The disease of trachoma is an easily preventable one and can be avoided by the following measures.
Stop Eye Rubbing - This is a relatively simple way to avoid infections from getting into the eye. The main mode of spread is from bodily secretions, as previously mentioned. Hence, the organism's mode of entry into the eye is by contact of the eye with the hands. Once eye rubbing is avoided, the organism has no way to gain access to the ocular surface and hence effectively prevents the infection.
Maintaining Hygienic Practices - Regular handwashing has been shown to drastically reduce the transmission of not only trachoma but also many other ocular viral and bacterial infections. Hand washing often and especially before greeting others, is the main mode to prevent the spread of trachoma.
Facial Hygiene - This prevents the transmission of infection by flies and airborne insects which harbor the infection and transmit it by contact. So, maintain facial hygiene with regular bathing and face washing with soap and water.
Public health measures include using toilets for defecation rather than in the open air and promoting hygiene of the surroundings by preventing stagnation of sewage water and garbage dumps.
This disease is seen in most parts of the world, and it is common among the poor and uncared. A few measures of personal hygiene and respect for our environment can go a long way in preventing this transmissible cause of blindness.
Conclusion:
Trachoma is the world’s leading infectious cause of visual impairment or blindness. Trachoma is a recurrent ocular infection caused by Chlamydia and is endemic in the developing world. It causes inflammation of the cornea and conjunctiva (keratoconjunctivitis) resulting from the obligate intracellular bacterium Chlamydia trachomatis.Poor sanitation, crowded living conditions, and insufficient clean water and toilets can lead to an increased risk of trachoma.
Long-term follow-up should be done for patients with the active or cicatricial disease. In addition, screening should be done in all women younger than 25, pregnant women, and women at increased risk of infection.
