Open access peer-reviewed chapter

Chlamydial Eye Infections

Written By

Seçil Özdemir Şahin

Submitted: 31 January 2023 Reviewed: 17 March 2023 Published: 26 April 2023

DOI: 10.5772/intechopen.111372

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Chlamydia - Secret Enemy From Past to Present

Edited by Mehmet Sarier

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Abstract

Chlamydiae are obligate intracellular bacteria causing mucosal infections. The leading agent Chlamydia trachomatis causes three clinical features in eyes: trachoma, neonatal, and adult inclusion conjunctivitis. A rare chlamydial conjunctivitis form called Lymphogranuloma Venereum conjunctivitis can be venereally transmitted. Seldomly Chlamydia psittaci and Chlamydia pneumonia may cause follicular conjunctivitis. Trachoma, the most sight-threatening chlamydial eye infection, lead to approximately 6 million blindness worldwide. Classical trachoma is characterized by chronic follicular keratoconjunctivitis, conjunctival scarring, and pannus formation. According to WHO at least two of the following should be present for clinical trachoma diagnosis: Superior tarsal follicles, limbal follicles or Herbert Pits, typical conjunctival scarring and vascular pannus. These should also be supported by laboratory findings such as organismal isolation and humoral or local antibody detection. The treatment consists of the personal acute sporadic trachoma treatment, the eradication of the disease, and complication management. For acute personnel treatment, systemical and topical forms of Tetracycline, Doxycycline, or Erythromycin are used. For the eradication of the disease, oral Azithromycin is a well-tolerated antibiotic. The management of the complications consists of surgical interventions for scars. In spite of developing hygiene standards and control programs, trachoma is still a major cause of infectious blindness.

Keywords

  • chlamydia
  • conjunctivitis
  • trachoma
  • inclusion
  • pannus
  • blindness

1. Introduction

The Chlamydiae, lacking cytochromes, unable to synthesize ATP, and are therefore obligate intracellular microorganism. By including both DNA and RNA, reproduction by binary fission, and being sensitive to antibiotics, they are classified as bacteria. Chlamydiae are gram negative and symbionts of diverse organisms ranging from human beings to amoebae. This family comprises 11 species that are pathogenic to humans or animals [1].

Some species that are originally animal pathogens, such as the avian pathogen Chlamydia psittaci, can be transmitted to humans [1, 2].

The main agents that infect humans and cause the widest range of diseases are Chlamydia trachomatis and Chlamydia pneumoniae [2, 3].

Strains of C. trachomatis are divided into three biovars: trachoma biovar, genital tract biovar, and lympho granuloma venereum biovar. These biovars are further subtyped by 15 serovars. The trachoma biovar (serovars A–C) is the leading cause of preventable blindness in developing nations, whereas the genital tract biovar (serovars D–K) is the most prevalent sexually transmitted bacterium [3]. As an absolute sexually transmitted pathogen, C. trachomatis is isolated more in developed countries. It is one of the most common sexually translated microorganisms in the world [4].

It must be noted that C. trachomatis infection may be asymptomatic in both sexes. This makes it harder to diagnose and manage infection control. This microorganism is the most common acute urethritis cause in sexually active young population. In acute urethritis due to C. trachomatis, cardinal findings like urethral discharge, itching and dysuria are so mild or sometimes do not exist [5].

Although its prevalence varies geographically, it accounts for 20–50% of nongonococcal urethritis cases and according to a study conducted in Turkiye, 84% of all urethritis cases are classified as nongonococcal [6].

C. trachomatis can cause epididymitis and male infertility in men.

The pathogen causes a wide range of diseases in women from acute cervicitis to pelvic inflammatory disease. The disease is usually asymptomatic, therefore, the patients unconsciously continue spreading the infection [7].

Another issue that makes the management of C. trachomatis infection harder is that it occurs most of the time as a coinfection with the other sexually transmitted pathogens [8]. Thus, early detection and management of C. trachomatis genital infections are very important [9].

For the time being, as culture and serological techniques are insufficient for diagnosis, with their high sensitivity and specificity, nucleic acid amplification tests like PCR are gold standard methods [10].

The World Health Organization estimated a prevalence of chlamydia at 4.2% (95% uncertainty interval: 3.7–4.7) worldwide among women aged 15–50 years in 2012. These figures correspond to approximately 131 million new cases of chlamydia annually (100–166 million). Ascending genitourinary infection may result in ectopic pregnancy, infertility, and chronic pelvic pain in some women [11].

The lymphogranuloma venereum biovar (serovars L1–L3) causes an invasive urogenital or anorectal infection.

Three Chlamydia species affect the eye by forming different types of conjunctivitis: C. chlamydia, C. psittaci, and C. pneumonia.

The ocular clinical manifestations of these three species are as follows [12]:

  1. C. trachomatis: Trachoma, adult inclusion conjunctivitis, neonatal inclusion conjunctivitis, and lymphogranuloma venereum conjunctivitis.

  2. C. psittaci: C. psittaci conjunctivitis.

  3. C. pneumonia: C. pneumonia conjunctivitis.

  4. C. trachomatis is the most frequent conjunctivitis causing one among all. Besides, it had been and still is, in endemic areas of the world causing trachoma and hereby blindness and low vision, which is a major problem of public health. Therefore C. trachomatis will be the prominent subject of this chapter.

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2. Chlamydia trachomatis eye infections

2.1 Conjunctivitis due to C. trachomatis

C. trachomatis is divided into 15 serological subgroups (serovars) according to monoclonal antibody-based tests. These serovars are associated with many medical conditions such as:

  1. A, B, Ba, and C: Trachoma is a serious eye disease that is endemic in certain regions of the world such as Asia and Africa, where close physical contact and poor hygiene conditions prevail. It is characterized by chronic follicular conjunctivitis and may cause visual damage.

  2. D, E, F, G, H, I, J, and K: Sexual infections and neonatal infections due to eye contact with infected mother’s cervix during the birth and adult eye infections in developed countries.

  3. L1, L2, L3: Lymphogranuloma venereum (LGV), which correlates with genital ulcer disease in tropical areas.

C. trachomatis is spread by direct and indirect contact such as fomites, flies, bedding, towels, etc. Family and school are the main transmission environments for transmission. In healthy individuals, the immune system can cope with a single attack. However, in recurrent episodes of infection, it succumbs to the infection [13].

2.1.1 Trachoma

Trachoma is one of the oldest diseases known. Even in the twenty-seventh century BC in China and seventeenth century BC in Egypt, there are findings about the disease [12].

It had been the leading cause of blindness in history and still is the leading cause of blindness by an infectious agent worldwide.

Trachoma is a public health problem in 44 countries and is responsible for blinding or visually impairing 1.9 million people. Of all blindness worldwide, it causes about 1.4% [14].

The number of people at risk of trachoma has decreased by 91% from 1.5 billion in 2002 to about 137 million in 2020. Besides, the number of individuals requiring surgery has reduced by 68% from 7.6 million in 2002 to 2.5 million in 2019 [15].

Based on June 2022 data, 125 million people live in trachoma-endemic areas and are at risk of trachoma blindness.

Trachoma is hyperendemic in many of the poorest and most rural areas of Central and South America, Australia, Africa, Asia, and the Middle East. Overall, Africa remains the most affected continent and the one with the most intensive control efforts.

For this most sight-threatening neglected tropical disease, World Health Organization (WHO) adopted a strategy called SAFE in 1993.

Elimination programs in endemic countries are being implemented using this WHO-recommended SAFE strategy. It consists of:

  • Surgery for the blinding phase treatment (trachomatous trichiasis);

  • Antibiotics to clear the infection, particularly mass drug administration of the antibiotic azithromycin, which is donated by the manufacturer to elimination programs, through the International Trachoma Initiative;

  • Facial cleanliness; and

  • Environmental improvement, particularly improving access to clean water and sanitation.

Most endemic countries have agreed to accelerate the implementation of this strategy to achieve elimination targets.

WHO’s mandate is to provide leadership and coordinate the international efforts aiming to eliminate trachoma as a public health problem, and to report on progress toward that target.

In the year 1996, WHO launched the WHO Alliance for the Global Elimination of Trachoma by 2020. The Alliance is a partnership that supports the implementation of the SAFE strategy by the Member States, and the strengthening of national capacity through epidemiological surveys, project evaluation, monitoring, and resource mobilization.

The World Health Assembly adopted resolution WHA51.11 in 1998, targeting the global elimination of trachoma as a public health problem with 2020 as the target date. The neglected tropical diseases road map 2021–2030, endorsed by the World Health Assembly in 2020 through its decision 73(33), sets the date 2030 as the new target for global elimination [16].

2.1.1.1 Clinical features

The discomfort degree caused by ocular infection with C. trachomatis ranges from minimal to severe. Most of the infections are asymptomatic. Trachoma begins as a follicular conjunctivitis of the upper palpebral conjunctiva with associated limbal follicles. The incubation period is approximately one week. Other early findings include a mucopurulent discharge, conjunctival papillary hypertrophy, a superiorly based superficial corneal pannus (invasion of the vessels to the cornea), and a fine epithelial keratitis. Clinically, trachoma can be divided into its acute (active) and chronic or late-stage manifestations, but acute and chronic signs can occur at the same time in the same individual. As a result, the inflammation causes scarring and cicatrization of the cornea, conjunctiva, and eyelids.

The blinding complications of trachoma occur as a result of conjunctival connective tissue proliferation. Arlt’s Line is the name given to a horizontal scar of the upper lid’s pretarsal conjunctiva. Another sequel pathognomonic for trachoma, Herbert’s pits are the delineated depressions that occur after cicatrization of the limbal follicles and the resultant clear spaces filled with epithelium. A homogenous clouding can be formed on the cornea as the superior pannus is regressed [17, 18, 19].

Resultants of conjunctival scarring, eyelid deformities as distichiasis, trichiasis, ectropion, and entropion may all occur. If sufficient transconjunctival scarring accumulates, contraction over the years will cause the upper lid to turn inward so that the eyelashes rub against the cornea and conjunctiva. This is named as trichiasis. If the whole lid edge is turned in, that condition is named as entropion. Scars around the bases of hair follicles can pull individual eyelashes into contact with the cornea, even entropion does not accompany. Corneal scarring, vascularization, ulceration, and even perforation resulting from these deformities can lead to visual acuity impairment and even blindness [20].

MacCallan developed a staging of the disease based on the conjunctival findings in 1908:

  1. STAGE 1: Early lymphoid hyperplasia with immature follicle formation in the upper tarsal conjunctiva, diffuse punctate keratitis and early signs of pannus.

  2. STAGE 2A: Mature upper tarsal follicles.

  3. STAGE 2B: Fluoride inflammation due to pretarsal and limbal follicle enlargement and papillary hypertrophy and complicated pannus.

  4. STAGE 3: Papillary hypertrophy regression, persistence of tarsal follicles, and onset of conjunctival scarring.

  5. STAGE 4: No acute inflammation, scars replacing papillae and follicles, and regression of the pannus.

The WHO has developed a more practical grading system for trachoma, structured around diffuse inflammation, follicular conjunctivitis, trichiasis, tarsal scarring, and corneal opacification presence. The WHO simplified trachoma grading system is widely used for research and program monitoring purposes.

This system includes five signs:

  • Trachomatous inflammation-follicular (TF): the presence of five or more follicles at least 0.5 mm in diameter in the central part of the upper tarsal conjunctiva;

  • Trachomatous inflammation-intense (TI): pronounced inflammatory thickening of the upper tarsal conjunctiva obscuring more than half the normal deep tarsal vessels;

  • Trachomatous scarring (TS): the presence of easily visible scars in the tarsal conjunctiva;

  • Trachomatous trichiasis (TT): at least a single eyelash rub on the eyeball or evidence of recent removal of in-turned eyelashes;

  • Corneal opacity (CO): easily visible corneal opacity over the pupil, so dense that at least part of the pupil margin is blurred when viewed through the opacity.

The presence or absence of each sign should be independently determined for each person examined. In the WHO system, the presence of TF and/or TI in one eye is necessary and sufficient to confer the diagnosis of acute trachoma [17, 21].

2.1.1.2 Laboratory diagnosis

Laboratory tests crucial for identifying C. trachomatis infections to confirm the diagnosis are [22]:

  1. Giemsa staining of smears: The most common procedure worldwide for identificating C. trachomatis infection is microscopic evaluation of the cells with Giemsa stain. The easiest and earliest method of laboratory diagnosis was by direct indication of the Halberstaedter-Prowazek bodies with Giemsa staining of conjunctival smears. Although it may not be sensitive enough in patients with nonaggressive ocular disease, Giemsa stain detects the inclusions in most of the cases with follicular or papillar trachoma [12].

  2. Antigen detection assays: The two tests available are Direct Fluorescent Antibody (DFA) and enzyme immunoassay (EIA). DFA with monoclonal antibodies is 90% sensitive and enzyme immunoassay (EIA) is believed to have a lower sensitivity. Both are used widely in routine.

  3. Tissue Culture Isolation: Isolation of C. trachomatis in Hella cells or McCoy cells, etc., is the most specific method and is considered the “gold standard.” However, sensitivity is low. C. trachomatis inclusions are detected either by Giemsa, Macchiavelli, or Gimenez staining or immunofluorescence assay after 48–72 h of incubation.

  4. Serology: The most common tests are complement fixation and microimmunofluorescence tests. Infection by any serotype of C. trachomatis causes a crossreactive antibody reaction against all the serotypes. The antibodies persist for a long period; therefore, serology has a limited role in the diagnosis of acute chlamydial infections [23].

  5. Nucleic acid amplification tests: The most commonly used tests are Polymerase Chain Reaction (PCR) assay and Ligase Chain Reaction (LCR) assay. Although they are the most sensitive and specific techniques for C. trachomatis detection, they are still not used for routine laboratory practices in poor countries due to the high cost and need for expertise [24].

2.1.1.3 Differential diagnosis

For the diagnosis of trachoma, although follicles are not pathognomonic, their presence in endemic areas should be a strong reason for suspicion. Pannus, conjunctival scarring, and trichiasis seen in these areas are almost always attributable to trachoma. Herbert’s pits are pathognomonic for previous trachomatous inflammation.

The most common differential diagnosis are as follows:

  1. Bacterial conjunctivitis.

  2. Adult inclusion conjunctivitis.

  3. Viral conjunctivitis.

  4. Allergic conjunctivitis.

Toxic follicular conjunctivitis is secondary to topical medications or cosmetics.

In areas where trachoma is endemic, pannus, conjunctival scarring, and trichiasis are almost attributable to trachoma. Corneal opacity, however, has many possible etiologies [25].

2.1.1.4 Treatment

2.1.1.4.1 Personal (acute sporadic trachoma) treatment

Systemical

Trachoma treatment consists of a 3–4 week use of oral antibiotics. The most commonly used medications are tetracycline (tetracycline 1 g/day or doxycycline 100 mg/day) or oral erythromycin. Erythromycin is indicated for less side effects in children, breastfeeding women, and pregnant. The clinical response may take 9–18 weeks.

Topical

Topical tetracycline or erythromycin ointment is used at least twice a day for 5 days each for 6 months. Reusing topical medication is especially useful where the disease is endemic and reexposure is expected [26].

Treatment aiming the eradication of the disease

Through the provision of adequate water and hygiene facilities combined with education to promote facial cleanliness and the use of hygiene facilities, it was shown that only face-washing habits even reduced trachoma prevalence [27].

Reducing the fly population by 90%, causing less transmission with eye-seeking flies can reduce the active trachoma prevalence by 60% [28].

To clear ocular C. trachomatis infection in endemic fields, antibiotic treatment may be helpful. Oral azithromycin (1 g/day for adults, 20 mg/kg/day for children) as a single dose is used [29]. It is claimed that in endemic areas, instead of topical treatment, a single dose of oral azithromycin is enough [30, 31].

Azithromycin is well tolerated and systemic antibiotic and is also effective for extraocular infection [32]. Topical tetracycline treatment 3–4 x 1 for 6 weeks is claimed to be equal to a single dose of azithromycin [33].

Treatment of the complications

Individuals with trachomatous trichiasis and entropion are at risk of corneal opacification and vision loss. To prevent these features from developing, the abrasive action of lashes on the cornea must be stopped by surgical correction of the eyelid margin, with epilation perhaps as an acceptable short-term option. For long-term solution, operation procedures for bilamellar tarsal rotation and posterior lamellar tarsal rotation (or Trabut) are recommended by WHO [34, 35, 36].

2.1.2 Neonatal inclusion conjunctivitis

The most common type of neonatal conjunctivitis worldwide is inclusion conjunctivitis. Inclusion conjunctivitis is caused by C. trachomatis serotypes D-K, which form chronic follicular conjunctivitis. Even though chlamydial infection typically affects the sexually active population, it can be transmitted to newborns by their infected mother during delivery. Infants exposed to the agent from the mother’s genital tract during delivery, develop chlamydial ophthalmia neonatorum. Approximately 30–50% of infants exposed at birth develop the disease. Neonatal chlamydial conjunctivitis occurs in 2–6% of all newborns [37, 38].

Neonatal chlamydial conjunctivitis is an acute infection of the conjunctiva that is characterized by edema and erythema of the eyelids, palpebral conjunctivae, and purulent eye secretion. It typically occurs 5–14 days after the birth, although it can present earlier. Usually, the infection has a mild and self-limiting course. However, severe diseases can occur. Corneal scarring secondary to peripheral corneal pannus and conjunctival scarring may occur [39, 40]. Laboratory procedures to identify C. trachomatis are necessary for diagnosis. One of the two most commonly used methods is Giemsa staining of the conjunctival swab. However, it has only 50–90% sensitivity and requires a trained technician for section evaluation. The other method is McCoy cell culture. It is very expensive and reaching the result takes 2–3 days. Fortunately, new laboratory techniques are available for diagnosis. The enzyme-linked immune assay test has a sensitivity of approximately 90% and a specificity of over 95% and gives results within 2 hours. Direct immunofluorescent monoclonal antibody staining of the conjunctival swab is probably the most useful stereological test and has a specificity of 77–90% with a sensitivity of over 95% for chlamydia. It can be read immediately. It can show diseases that other tests miss. DNA detection tests can also be used. These tests have 90% sensitivity and almost 100% specificity [41].

The therapy objective for neonatal chlamydial conjunctivitis includes both the regression of conjunctivitis and the eradication of respiratory colonization. Therefore topical treatment is insufficient. An oral erythromycin treatment of 50 mg/kg/day in four divided doses for 2 weeks is recommended. If a total recovery is not observed, a second regime of the therapy may be given. The oral treatment should be given to the mother and her sexual partner, with 500 mg tetracycline or 500 mg erythromycin four times a day for 7 days. If pregnancy or breastfeeding exists erythromycin should be chosen [42].

Ocular prophylaxis for newborns has been found to be ineffective in protecting against chlamydial conjunctivitis. Several developed countries have stopped ocular prophylaxis of newborns and replaced it with routine treatment and prenatal screening of pregnant with a sexually transmitted infection [43].

2.1.3 Adult inclusion conjunctivitis

As neonatal inclusion conjunctivitis, adult inclusion conjunctivitis occurs with C. trachomatis D-K serotypes. The transmission of the agent is by sexual or hand-eye contact. Epidemiology revolves around sexual contact. The mode of transmission is through orogenital activities and transmission of genital secretions from hand to eye. The incubation period is 4–12 days. Inclusion conjunctivitis is predicted to develop in one in 300 patients with vernal chlamydial infection. In addition, C. trachomatis is the most common cause of chronic follicular conjunctivitis and is responsible for 20% of acute conjunctivitis cases. Because the disease is difficult to distinguish from the clinical findings of early trachoma, the term “paratrachoma” has been used to describe the entire spectrum of the disease with venerally transmitted chlamydial infection [44, 45].

The severity of symptoms in patients with inclusion conjunctivitis is very extensive. Some patients present as acute and mucopurulent conjunctivitis but, most patients have mild symptoms lasting for weeks or months Keratitis may develop in the second week of onset. Corneal involvement consists of superficial punctate keratitis, small marginal and central infiltrates, subepithelial infiltrates, limbal swelling, and superior limbal pannus. The disease imitates acute atopic conjunctivitis or other infectious conjunctivitis because, the signs and symptoms are insidious and most patients have similar nonspecific complaints such as unilateral mucous secretion, hyperemic eyes, crusting of eyelashes, glued eyelids, swollen eyelids, photophobia, itching, lacrimation, foreign body sensation, irritation, and blurred vision [46].

Diagnostic tests for chlamydial keratoconjunctivitis include conjunctival cytological examination, inoculation of susceptible cell lines followed by observation of cytopathic effect or visualization using various chemical or immunological staining agents, eye tears for various antibodies, and detection of chlamydial antigens in conjunctival and corneal specimens. Although the sensitivity of Giemsa staining is low, it is costly and time-consuming, this traditional cytological investigation is still the “gold standard,” as isolating an infectious agent is definitive and allows further characterization. The detection of C. trachomatis DNA from ocular smears using commercial PCR assays was shown to be as valid as using urogenital samples and reached 95.71% in sensitivity and 90.00% in specificity. Therefore, PCR tests may be a quick and ideal tool for detecting ocular C. trachomatis infection [47].

As the infection is not limited to conjunctiva, systemic antibiotic use is recommended. Moreover, the sexual consorts must also receive a full course of therapy. Simultaneous treatment of all sexual partners is important to prevent reinfection. The recommended treatment, given for 3 weeks, includes either oral doxycycline 100 mg twice a day, oral tetracycline 500 mg four times a day, or oral erythromycin 500 mg four times a day. Tetracycline should not be used in pregnant or lactating women [42].

2.2 Lymphogranuloma venereum conjunctivitis

Lymphogranuloma venereum conjunctivitis is a very rare chlamydial conjunctivitis caused by C. trachomatis serotypes L1, L2, and L3. These agents classically cause a venereal disease characterized by suppurative inguinal or femoral lymphadenopathy. Occasionally, there are extragenital manifestations of the disease including aseptic meningitis, hepatitis, and conjunctivitis. The first ocular manifestations are the redness and edema of the eyelids. Other ocular manifestations are follicular hypertrophy, hyperemia, chemosis, and large granulomas. Pannus formation and peripheral superficial keratitis may occur. In some cases, phlyctenular conjunctivitis is present too. Episcleritis, uveitis and optic neuritis are among other rare clinical conditions reported. A large preauricular lymph node may be palpable.

The laboratory diagnosis is based on the microscopic detection of inclusion bodies, macrophages, and monocytes in Giemsa-stained conjunctival smears.

For treatment, oral tetracycline, 500 mg four times a day, for 4 weeks or oral doxycycline, 100 mg two times a day, for 4 weeks is used.

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3. Other chlamydial conjunctivitis

Other chlamydia subgroups that should be considered as causative agents of conjunctivitis are C. psittaci and C. pneumoniae.

C. psittaci is the causative agent of psittacosis, which is seen in people who have bird contact in their professional or private life. This infection may produce a wide spectrum of clinical manifestations, ranging from asymptomatic infection to severe systemic disease with severe pneumonia. The Association of C. psittacine with ocular adnexal lymphoma in humans has been reported.

C. psittaci is a cause of follicular conjunctivitis and epithelial keratitis. In cases with long-lasting follicular conjunctivitis with a story of close bird contact C. psittaci should be kept in consideration. The isolation of inclusion bodies in epithelial cells and the microorganism in tissue cultures are necessary for the diagnosis.

One of the most important differences between C. psittaci and C. trachomatis is the time required for treatment. While long-term treatments are required in C. psittaci eye infection, a single 1 g azithromycin dose is considered sufficient in C. trachomatis conjunctivitis. In C. psittaci conjunctivitis, oral tetracycline 500 mg four times a day or oral doxycycline 100 mg two times a day for 6 weeks should be used for treatment.

C. pneumoniae is a rare cause of chronic follicular conjunctivitis. For cases with long-lasting, resistant conjunctivitis, respiratory contact with cats having C. pneumoniae infection should be kept in mind. Limited documentation exists relating to C. pneumoniae seropositivity in cases of chronic follicular conjunctivitis. For clinicians treating patients presenting with chronic conjunctivitis unresponsive to conventional measures, obtaining serologic studies for C. pneumoniae may identify this association. Oral tetracycline 3–4 times a day is used for treatment [48].

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4. Conclusions

Although the topic of this chapter was Chlamydial Eye Infections, the main issue was definitely trachoma. Being an ancient disease and a major blindness cause, C. trachomatis has been a great concern of medicine for centuries. As technological improvements gave us new possibilities to understand the nature of this blinding microorganism, the endemic fields have been reduced, but the WHO could not reach the goal of eliminating trachoma, yet. The SAFE strategy provides a targeted way to speed up the process of a general improvement in living conditions and hygiene that is needed to eliminate it in the most disadvantaged areas in the developing world. As increasing resources are brought to bear, the likelihood of eliminating blinding trachoma by 2030 becomes stronger.

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Conflict of interest

The author has no conflict of interest to declare.

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Written By

Seçil Özdemir Şahin

Submitted: 31 January 2023 Reviewed: 17 March 2023 Published: 26 April 2023