Trachome

Trachoma is a neglected tropical eye disease arising from infection with conjunctival strains of Chlamydia trachomatis ^[1][2][3][5]. It constitutes a disease complex linking a recurrent, mostly subclinical infectious-inflammatory process in children with a later non-communicable cicatricial and blinding process in some adults ^[5].

Active inflammatory trachoma is marked by conjunctival inflammatory change and is common in preschool children in endemic areas ^[1][3]. Repeated infection across the lifetime leads to trachomatous conjunctival scarring, inward turning of the eyelid, and trichiasis with eyelashes abrading the globe, causing pain and light intolerance ^[1][3][5]. Corneal scarring and irreversible opacity may follow, producing visual impairment or blindness, with at least 150 lifetime infections typically required to precipitate trichiasis ^[3][5].

Active trachoma affects up to 90% of preschool-aged children in endemic localities, with infection frequency and duration declining with age ^[1][3]. The disease is a public-health problem across rural impoverished regions of Africa, Central and South America, Asia, Australia, and the Middle East, causing blindness or visual impairment in about 1.9 million people and accounting for roughly 1.4% of global blindness ^[1][3]. Africa is the most affected continent and the focus of intensive control; as of early 2024, 18 countries were validated as having eliminated trachoma as a public-health problem ^[3]. In 2022, over 129,000 people received surgical care and 36.2 million were treated with antibiotics, yet the disease still imposes an estimated US$8 billion annual productivity loss ^[3].

The organism passes from person to person through direct or indirect transfer of ocular and nasal discharges from infected individuals, with young children serving as the principal reservoir ^[1][3]. Particular fly species can mechanically carry infectious discharges between people ^[1][3]. Transmission chiefly occurs within households where close contact with active cases is common ^[1].

The WHO-endorsed SAFE strategy guides elimination efforts through surgery for trichiasis, antibiotic administration, promotion of facial cleanliness, and environmental improvement ^[4]. Mass antibiotic treatment and environmental interventions aim to lower infection prevalence and interrupt transmission in endemic communities ^[4]. Continued application of these measures has yielded country-level elimination validations and large-scale treatment coverage, though sustained effort remains necessary ^[3][4].

1. 1 World Health Organization. Trachoma [Internet]. cited 20 May 2026. Available from: https://www.who.int/news-room/fact-sheets/detail/trachoma
2. 2 World Health Organization. Trachoma [Internet]. cited 20 May 2026. Available from: https://www.who.int/news-room/questions-and-answers/item/trachoma
3. 3 World Health Organization. Trachoma [Internet]. cited 20 May 2026. Available from: https://www.who.int/health-topics/trachoma
4. 4 Evans JR et al. Antibiotics for trachoma. Cochrane Database Syst Rev. 2019 Sep 26. PMID: 31554017. doi: 10.1002/14651858.CD001860.pub4. PubMed: https://pubmed.ncbi.nlm.nih.gov/31554017/
5. 5 Solomon AW et al. Trachoma. Nat Rev Dis Primers. 2022 May 26. PMID: 35618795. doi: 10.1038/s41572-022-00359-5. PubMed: https://pubmed.ncbi.nlm.nih.gov/35618795/