This document provides an overview of trachoma, including its epidemiology, etiology, pathogenesis, clinical features, classification, diagnosis, and prevention and treatment. Trachoma is caused by Chlamydia trachomatis and is the leading infectious cause of preventable blindness worldwide, primarily affecting poor, rural areas with limited access to clean water and sanitation. The WHO's SAFE strategy of surgery, antibiotics, facial cleanliness, and environmental improvement is the recommended approach to control and eliminate trachoma as a public health problem.

1. D R M O H A M M E D L U K M A N
D E P A R T M E N T O F F A M I L Y M E D I C I N E ,
A K T H , K A N O
M O D E R A T O R : D R R A B I . Y . S A N I
C O N S U L T A N T O P T H A L M O L O G I S T ,
A K T H , K A N O
TRACHOMA:
AN OVERVIEW
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2. OUTLINE
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 INTRODUCTION
 EPIDEMIOLOGY
 ETIOLOGY
 PREDISPOSING FACTORS
 PATHOGENESIS
 CLINICAL FEATURES
 CLASSIFICATION
 DIAGNOSIS
 PREVENTION AND TREATMENT

3. INTRODUCTION
 Trachoma is a neglected tropical disease and the leading
infectious cause of preventable blindness worldwide.
 It is a chronic bilateral kerato-conjunctivitis.
 Affects primarily the superficial epithelium of the conjunctiva
and the cornea simultaneously.
 The word trachoma originates from the Greek word ‘rough’
which describes the appearance of the cornea when the
disease is chronic.
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4. Map of trachoma endemic countries in 2009.
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Burton MJ, Mabey DCW (2009) The Global Burden of Trachoma: A Review. PLoS Negl
Trop Dis 3(10): e460. doi:10.1371/journal.pntd.0000460
http://www.plosntd.org/article/info:doi/10.1371/journal.pntd.000046

5. EPIDEMIOLOGY
 Trachoma is hyper endemic in many of the poorest and most rural areas
 Trachoma can occur worldwide but is more common in the Middle East, North
Africa, sub-Saharan Africa, and areas of southern Asia and China
 It is responsible for blindness or visual impairment of about 1.9 million people
 It causes about 1.4% of all blindness worldwide
 Africa remains the most affected continent
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6. ETIOLOGY
Causative agent
 Chlamydia trachomatis
 A gram negative obligate intracellular parasite
 Psittacosis lymphogranoloma- trachoma. (PLT group)
 Serotypes A, B, Ba and C
 Incubation period of trachoma varies from 5-21 days.
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7. ETIOLOGY
Source of infection
 Conjunctival and nasal discharge
Mode of transmission
 Direct spread.
 Vector transmission through flies
 Personal contact
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8. ETIOLOGY
Predisposing factors
1. Poverty/Poor socioeconomic status :
 Poor (personal) hygiene
 Overcrowding
 Water shortage
 Poor sanitation
 Inadequate latrine and sanitary facilities
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9. ETIOLOGY
2. Age; Infancy and childhood
3. Sex; Females both in number and severity of
infections
4. Climate; Dry and dusty climates
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10. Predisposing factors
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11. PATHOGENESIS
 Infection of the eye with C. trachomatis causes inflammation
 Associated predominantly with lymphocytic and monocytic
infiltrates with plasma cells and macrophages
 The intense inflammatory infiltrates leads to the formation of
follicles and papillae within the conjunctiva
 Recurrent conjunctival infection causes prolonged
inflammation that leads to conjunctival scarring
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12. PATHOGENESIS
 Atrophy of the conjunctival epithelium.
 Loss of goblet cells and replacement of vascular sub-
epithelial stroma with thick bands of collagen
 Scar formation leads to entropion and trichiasis due to
contraction and buckling of the upper eye lid tarsals plates
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13. PATHOGENESIS
 The development of acute disease in the first decade of
life which continues with slow progression, until the
disease becomes inactive in the second decade of life
 The sequelae (scarring or cicatrical phase) occur usually
after 20 years of the disease
 Peak incidence of blinding sequelae is seen in the 4th and
5th decade.
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14. PATHOGENESIS
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15. CLINICAL FEATURES
Symptoms
 In the absence of secondary infection symptoms are
minimal and include
 mild foreign body sensation in the eyes
 occasional lacrimation
 slight stickiness of the lids
 scanty mucoid discharge
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16. CLINICAL FEATURES
 In the presence of secondary infection, typical symptoms of acute
muco-purulent conjunctivitis develop
 Itching of the eyes
 Excessive lacrimation
 There may be pain and photophobia
 Exudation
 Edema of the eyelids
 Redness
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17. CLINICAL FEATURES
Conjunctival signs
1. Congestion of upper tarsal and bulbar conjunctiva
2. Conjunctival follicles
3. Papillary hypertrophy
4. Conjunctival scarring
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18. CLINICAL FEATURES
Corneal signs
1. Superficial keratitis
2. Herbert follicles
3. Pannus
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19. CLINICAL FEATURES Contd
4. Corneal ulcer may sometime develop at the
advancing edge of pannus
5. Herbert pits are the oval or circular pitted scars,
left after healing of Herbert follicles
6. Corneal opacity which is the end point/result of
trachomatous corneal lesions
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20. CLASSIFICATION
WHO classification : FISTO suggested by WHO in 1987.
This describes the consequence of trachomatous
inflammation
1. TF: Trachomatous inflammation-follicular
2. TI : Trachomatous inflammation intense
3. TS: Trachomatous scarring
4. TT: Trachomatous Trichiasis
5. CO: Corneal Opacity
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21. NORMAL TARSAL CONJUNCTIVA

22. TRACHOMATOUS FOLLICULAR

23. TRACHOMATOUS INTENSE

24. TRACHOMATOUS SCARRING

25. TRACHOMATOUS TRICHIASIS

26. CORNEAL OPACITY
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27. WHO CLASSIFICATION OF TRACHOMA
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28. DIAGNOSIS
A. Clinical diagnosis of trachoma
 is made from its typical signs
 at least two sets of signs should be present out of
the following:
1. Conjunctival follicles and papillae
2. Pannus
3. Epithelial keratitis near superior limbus
4. Signs of cicatrisation or its sequelae
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29. DIAGNOSIS
B. Laboratory diagnosis.
 laboratory tests are employed for research purposes only
and include.
1. Conjunctival cytology using Giemsa stained smears
2. Detection of inclusion bodies in conjunctival smear may
be possible by Giemsa stain, iodine stain or immuno-
fluorescent staining
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30. DIAGNOSIS
3. Enzyme-linked immuno-sorbent assay (ELISA) for
chlamydial antigens
4. Polymerase chain reaction (PCR)
5. Isolation of chlamydia via cell culture
6. Detection of specific antibodies using micro
immunofluorescence (micro-IF) method
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31. Prevention & Treatment
No trachoma vaccine is available, but
prevention is possible.
The WHO developed a strategy (titled
SAFE) to prevent trachoma, with the goal
of eliminating it by 2020. The strategy is
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32. WHO RESPONSE
1. SAFE strategy
 Adopted in 1993
 The mandate is to provide leadership and coordination of
international efforts aimed at eliminating the disease as a
public health problem
2. WHO Alliance for the Global Elimination of Trachoma
by 2020 (GET2020)
 Launched in 1996
 Supports implementation of SAFE strategy by member
states
 Strengthening of the national capacity through
epidemiological surveys, monitoring , project evaluation
and resource mobilization
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33. WHO RESPONSE
WHO definition of elimination of trachoma as a public
health problem
1. A prevalence of TT of ≤ 0.2% in adults over 15 years
( approximately 1 case in 1000 people)
2. A prevalence of ≤ 5 % of TF in children aged 1 to 9
years
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34. WHO RESPONSE
 Every year, a critical meeting of WHO GET 2020 is
held to chat the progress towards elimination of
trachoma
 As at April 2017, 10 more countries have reported to
achieve elimination goals
 These countries are : Cambodia, China, Gambia, Ghana,
Iran, Lao people Democratic Republic, Mexico,
Morocco, Myanmar and Oman
 This signifies a major milestone in the campaign to
eliminate trachoma
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35. PREVENTION AND TREATMENT
 The SAFE strategy developed by WHO is key in the Management and
Prevention
 Surgery to treat the blinding stages of the disease (trachomatous trichiasis)
 Antibiotics to clear infections particularly mass administration of
Azithromycin
 Facial cleanliness to prevent spread of bacteria
 Environmental improvement particularly improving access to water and
sanitation
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36. PREVENTION AND TREATMENT
 WHO recommends 2 antibiotics for trachoma control
Oral azithromycin and tetracycline eye ointment
 Azithromycin is the drug of choice
 The trachoma program in a number of countries are
beneficiaries of philanthropic donation of this medicine
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37. PREVENTION AND TREATMENT
 The aim of antibiotic treatment is to reduce or eliminate
the reservoir of infection in the family
 Thus the infected person and all family members should
be treated
 Dose of Azithromycin : children 20mg/kg as a single dose
Adult 1g as a single dose
 In hyperendemic areas, the whole community is eligible
for antibiotic treatment
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38. Facial Hygiene
Proper hygiene practices include:
 Face washing and hand-washing.
 Controlling flies.
 Proper waste management.
 Improved access to water.
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39. CONCLUSION
 Trachoma is a disease of great public health
importance and a major cause of irreversible
blindness
 The SAFE strategy advocated by WHO is key in the
prevention of the disease and in treatment and
prevention of complications including blindness
 Health education especially at community level
creates awareness and will help in reducing spread
and the transmission of the disease/condition
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40. REFERENCES
 Khurana AK. Diseases of the Conjunctiva. In: Singh A,
editor. Comprehensive Ophthalmology. 4th ed. New
Delhi: New age international (P) Limited; 2007. 51 -88
 Kanski JJ, Nishal KK. The conjunctiva. In: Tyagi A,
Horne G, Delaney Y, Assi A, Wheatcroft S, editors.
Kanski Ophthalmology : Clinical signs and differential
diagnosis. 1st ed. London :Harcourt Publishers . 2000. 68
– 103
 Trachoma. World health organization.
http://www.who.int/mediacentre/factsheets/fs382/en/
Assessed 26/08/19
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41. REFERENCES
 Wang N. Deng D,Tian L. A review of trachoma history in
China :research, prevention and control. Sci China Life
Sci. 2016; 59 (60) : 541 – 547
 Tailor HR. Trachoma in Asia – a disappering scourge.
Taiwan J Ophthalmol. 2016, 6 (2) : 55 -57
 Rabiu MM, Muhammed N, Isiyaku M.Challenges of
Trachoma control : An assessment of the situation in
northern Nigeria. Middle East Afr J Ophthalmol. 2011; 18
(2):115 - 112
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