Trachoma and trichiasis
Author Dr Jacki Mein
Expert reviewer Professor Hugh Taylor
Trachoma is a bacterial eye disease of poor socioeconomic conditions, including overcrowding and poor water/sewerage services.29 Active trachoma (usually graded as TF: trachoma follicular) predominantly affects young children and is a contagious infection of the eye by specific, non-genital strains of the bacterium Chlamydia trachomatis. Multiple infections cause conjunctival scarring (TS: trachomatous scarring) leading to eyelid contraction and inturned margin (entropion) over decades (TT: trachomatous trichiasis). The resulting inturned eyelashes rub on the eyeball causing painful corneal scarring and opacity (CO: corneal opacity).
Trichiasis occurs when at least one eyelash rubs on the eyeball, or there is evidence of recently removed eyelashes because of eyelash inturning.30 If not treated with surgery to the eyelid to correct inturned eyelashes, corneal scarring can end in blindness in later adult life, 20–40 years after the initial trachoma infections. Australia is the only developed country in the world that still has areas of trachoma and trichiasis.31 These occur almost exclusively in remote Aboriginal populations in the Northern Territory, South Australia and Western Australia. The National Indigenous Eye Health Survey1 found that the overall rate of active trachoma (TF: trachoma follicular) in children under 5 years is 3.8%.1 There was a steep rise in prevalence from urban and remote (0.6–1.6%) to very remote regions (7.3%), where 50% of communities had endemic rates (>5%) of active trachoma. Within communities trachoma is strongly clustered by households32 and within households clustered by sleeping rooms,33 suggesting continued transmission depends on close prolonged contact.
From the National Indigenous Eye Health Survey, the community prevalence rates of trachomatous scarring ranged from 0% to 53% (overall 15.7%), trichiasis prevalence from 0% to 14.6% (overall 1.4%) and corneal opacity from 0% to 3.3% (overall 0.3%). These data show that blinding endemic trachoma remains a major public health problem in very remote communities and given the long delay in onset, scarring and blindness will persist for decades after trachoma is eliminated.1
Evidence of the effectiveness of preventive interventions
The Communicable Disease Network of Australia Guidelines for the public health management of trachoma in Australia, 2006, are based on the World Health Organization (WHO) SAFE strategy.34 The acronym SAFE encompasses an integrated approach to prevention including Surgery for trichiasis, Antibiotics to reduce community reservoirs of trachoma infection, Facial cleanliness in preschool children, and Environmental measures to reduce trachoma transmission. There is good evidence to support all SAFE strategy components.34 Chlamydia vaccine development has been flagged as a possible complementary strategy to SAFE, but is currently many years away.35
With rapid household spread and high mobility of families in remote areas, trachoma control and prevention is best undertaken at regional levels with coordination of screening and mass treatment.34 Primary health practitioners have an important role in partnering with regional population health units to implement these programs, and they can be linked to other child health screening assessments (eg. anaemia and nutrition assessments). Environmental strategies such as improved water access, access to toilets, waste and fly control, and reduced household overcrowding also play a key role in trachoma control.34
The diagnosis of trachoma is based on clinical grounds. Laboratory tests are not recommended, except perhaps to exclude other bacterial infection.36 There is no evidence that opportunistic examination and treatment for trachoma in individual children improves community trachoma outcomes, but it may relieve symptoms or prompt/inform discussions about the need for treatment of households and mass treatment programs. There is evidence of effectiveness for these larger scale community treatment programs, with a single dose of azithromycin at 20 mg/kg orally up to 1 g repeated at least annually.37
The decision to screen and treat individuals and their contacts should, therefore, be based on patient origin from endemic area, age and symptoms, as well as liaison with regional trachoma control programs. Unfortunately, screening and treatment for trichiasis have not been reported in a systematic way in most Australian control programs,34 but with the advent of a National Trachoma Surveillance and Reporting Unit this is improving.38 In trachoma endemic areas (ie. where active trachoma prevalence in children under 10 years is >5%) annual screening programs are indicated. WHO does not recommend a particular season for screening and treatment. Even within very remote regions there may be variation in trachoma prevalence in both place and time, due to population mobility and environmental factors, but instability of prevalence estimates are usually due to small survey numbers, variable screening coverage and remote clinical staff screening skill. The Australian guidelines recommend annual screening until reductions in prevalence to <5% are sustained for over 5 years.34
In areas where trachoma and trichiasis is endemic, adults aged 40–54 years should be screened every 2 years, and those aged 55+ should be screened annually for trichiasis, for example as part of an annual health assessment.34,39 The ‘3Ts’ need to be remembered for the trichiasis examination: Think to do it, use a Thumb to lift the lid so the lashes lift away from the eye, and use a Torch to provide enough light to see the dark lashes. Blindness due to trichiasis is irreversible once it has occurred but progression to blindness can be temporarily halted by surgery, because it stops eyelash rubbing and therefore prevents corneal opacity.40 Surgery however does not alter the natural history of trichiasis; therefore, post surgery, patients who still have vision should be followed up annually to screen for recurrence.41 Other trichiasis complications such as dry eyes need symptomatic treatment to prevent further complications.
Recommendations: Eye health
|Preventive intervention type||Who is at risk?||What should be done?||How often?||Level/strength of evidence|
||People living where trachoma is endemic (>5% prevalence of active trachoma in young children)
||Implement a community screening program in partnership with regional population health units to assess the prevalence of active trachoma
No community screening is required where prevalence is below 5% of children for 5 consecutive years
|As per national guideline recommendations (see Resources)
|Adults aged >40 years raised in trachoma endemic area
||Perform eye examination to ascertain corneal scarring and/or the presence of trichiasis
||2 yearly (age 40–54 years)
Annually (age 55+ years)
||Those with trichiasis,* refer to an ophthalmologist for surgery
||All children from trachoma endemic areas
||Recommend to families the importance of the following in the prevention and control of trachoma:
- facial cleanliness of children
- effective rubbish disposal and other fly control measures
- regular screening, and treatment of infection
|Opportunistic and as part of an annual child health assessment
||People living where trachoma is endemic (>5% prevalence of active trachoma in young children)
||Treat case and all household contacts using community based single dose azithromycin (A) on an annual basis
||As per state and territory protocols
||Assess housing situation for overcrowding and refer to social support services for housing assistance if indicated. (See Chapter 7: Hearing loss)
||Implement joint health promotion strategies with state/territory government public health units and local shire councils for fly control strategies and other environmental health standards
||As per state/territory government plans
|* Trichiasis is diagnosed when at least one eyelash rubs on the eyeball, or there is evidence of recently removed eyelashes because of eyelash in-turning30
Full report on National Indigenous Eye Health Survey
Australian guidelines for the management of diabetic retinopathy (NHMRC)
www.nhmrc.gov.au/ _files_nhmrc/file/publications/ synopses/di15.pdf
Patient factsheets on diabetic retinopathy (CERA)
www.cera.org.au/ uploads/CERA_factsheet_Diabetic Retinopathy.pdf
Guidelines for the public health management of trachoma in Australia (Australian Government)
www.health.gov.au/ internet/main/publishing.nsf/Content/ 1EBA6A6D1AEB9569CA2571570008FB93/$ File/Trachoma2.pdf
At cost vision screening kits including E-test charts, which are suitable for primary care including remote use (CERA)
www.cera.org.au/ our-work/resources/ vision-screening-tools.
Grading card showing the simplified trachoma grading system, which includes high quality clinical pictures of trachoma and trichiasis (2-sided), available free (WHO)
www.who.int/ blindness/publications/ trachoma_english.jpg
Comprehensive practical documents including control program, surgery and community support guides (WHO)
www.who.int/ blindness/causes/ trachoma_documents/en.
- National Indigenous Eye Health Survey Team. Minum Barreng (tracking eyes) full report: National Indigenous Eye Health Survey, version 2. NIEHS, 2009. Cited October 2011. Available at www.iehu.unimelb.edu.au/ publications/the_national_indigenous _eye_health_survey.
- Figuiera E. Trachoma: An evidence based global and Australian perspective. Sydney: The Fred Hollows Foundation, 2006.
- Thylefors B, Dawson CR, Jones BR, West SK, Taylor HR. A simple system for the assessment of trachoma and its complications. Bull World Health Organ 1987;65:477–83.
- Mak DB, O’Neill LM, Herceg A, McFarlane H. Prevalence and control of trachoma in Australia, 1997–2004. Comm Dis Intell 2006;30:236–47.
- Mabey DCW, Bailey RL, Ward ME, Whittle HC. A longitudinal study of trachoma in a Gambian village. Implications concerning the pathogenesis of chlamydial infection. Epidemiol Infect 1992;108:343–51.
- Bailey RL, Osmond C, Mabey DC, Whittle HC, Ward ME. Analysis of the household pattern of trachoma in a Gambian village using a Monte Carlo simulation procedure. Int J Epidemiol 1989;18:944–51.
- Communicable Diseases Network Australia and Department of Health and Ageing. Guidelines for the public health management of trachoma in Australia. Canberra: Commonwealth of Australia, 2011. Cited January 2012. Available at www.health.gov.au/ internet/main/publishing.nsf/ Content/cda-cdna-pubs-trachoma.htm.
- World Health Organization. 10th Meeting of GET2020 Report. Making progress toward the global elimination of blinding trachoma. Geneva: WHO, 2006.
- Mabey DC, Solomon AW, Foster A. Trachoma. Lancet 2003;362:323–29.
- Taylor HR, Gruen R. Global evidence mapping initiative. antibiotic treatments of trachoma: a systematic review. Melbourne: University of Melbourne and Monash University, 2010.
- Deapartment of Health and Ageing. Surveillance reports for active trachoma annual reports. Canberra: DHA, 2010. Cited October 2011. Available at www.health.gov.au/ internet/main/publishing.nsf/ Content/cda-trachoma-annlrpt.htm.
- Taylor V, Ewald D, Liddle H, Warchivker I. Review of the implementation of the National Aboriginal and Torres Strait Islander Eye Health Program. Canberra: Centre for Remote Health, 2004.
- World Health Organization. London School of Hygiene and Tropical Medicine and the International Trachoma Initiative. Trachoma control: a guide for program managers. Geneva: WHO, 2006.
- Office for Aboriginal and Torres Strait Islander Health. Specialist eye health guidelines for use in Aboriginal and Torres Strait Islander populations. Cataract, diabetic retinopathy, trachoma. Canberra: Commonwealth of Australia, 2001.
- Tellis B, Fotis K, Keeffe JE, Taylor HR. Trachoma surveillance annual report,2008. A report by the National Trachoma Surveillance Reporting Unit. Commun Dis Intell 2009;33(3):275–90.