This section describes trachoma and its impact on Indigenous populations in Australia using the parameters for measuring the importance of a health related event and the public surveillance system with which it is monitored, as set out in the CDC Guidelines21.
3.2.1 Indices of frequencyThe most recent estimate (2008), suggests that there are currently about 40 million people with active trachoma and 8.2 million with trichiasis worldwide22. The global burden of disease from trachoma was estimated by Frick et al23, who reported that, in 2000, annual disability-adjusted life years (DALYs)24 was 3.6 million (note that the authors excluded YLL because they considered the estimate to be unreliable), with 72% of these DALYs occurring within sub-Saharan Africa and 80% of lifetime DALYs occurring in women. Furthermore, trachoma is reported to contribute 4% of the global burden of blindness25. Estimates of the burden of trachoma suffer from several weaknesses, one of which is the limited supply of reliable data on the prevalence of disease sequelae in endemic populations. There are few robust population-based surveys that can be used to estimate the number of affected peopl26.
Australia is the only developed country of the 55 trachoma endemic countries listed by the WHO to still have prevalent trachoma cases in certain region27. Trachoma is known to be endemic in Aboriginal and Torres Strait Islander populations in some parts of the NT, SA and WA. In 2008, trachoma was identified in children in NSW and Queensland, where trachoma was thought to be eradicated28.top of page
Figure 3.1, depicting the distribution of active trachoma in the regions in Australia, shows that it occurs in focal pockets in some Indigenous populations. There are wide variations in trachoma prevalence between Indigenous populations within the same area. Non-Indigenous people and urban populations in these regions are not affected by trachoma. The communities affected by trachoma comprise only a small proportion of the whole population in these regions. For example, in the Kimberley in 2003, the regional prevalence of active trachoma was 11%, but trachoma prevalence in screened schools/communities ranged from 5% to 60% (some towns and coastal Aboriginal and Torres Strait Islander communities in which trachoma is no longer endemic were not screened29).
Figure 3.1: Prevalence of active trachoma in Australia, children 1-9 years, 2008
Source: Tellis B et al (2009). Trachoma surveillance report 2008, National Trachoma Surveillance and Reporting Unit
*No active trachoma was found, however, only nine children were examined in this area
Note: The majority of active trachoma data in Australia comes from school surveys conducted in Indigenous populations
Figure 3.2: Active trachoma (TF) prevalence in Indigenous children 5-15 years of age, 2008
Source: Taylor, H et al 2009. National Indigenous eye health survey, Centre for Eye Research Australia, The University of Melbourne, p12Overall the survey found that 3.8% of the Indigenous children aged 5-15 years screened had active trachoma. The prevalence rates were highest in very remote areas both coastal and inland at 7.2% and 7.3% respectively. Six of the ten very remote communities screened were found to have endemic trachoma (defined as a prevalence of active trachoma in 5-9 year olds, greater than 5%, the highest prevalence was 28%).
Table 3.1 taken from the 2008 Trachoma Surveillance Report, shows that, in 2008, screening was conducted in 287 communities, of which 235 (82%) were identified as ‘at risk’. Of these, 121 (51%) of the communities were screened covering 4,650 children (estimated as 23% coverage). In total 997 children aged 1 to 9 years were identified with active trachoma, which represents a prevalence rate of 21%.top of page
Table 3.1: Community coverage, screening coverage and prevalence of trachoma for Aboriginal children aged 1 to 9 years, 2008
Number of communities ‘at risk’ (2008)
Community coverage: Number of communities screened*
Screening coverage: Number of children examined**
Prevalence of active trachoma (children 1 to 9 years)
Source: Tellis B, Fotis K, Dunn R, Keeffe J and Taylor H (2009). Trachoma surveillance report 2008, National Trachoma Surveillance and Reporting Unit, Centre for Eye Research Australia
*Community coverage is calculated by using the number of communities that were screened as a proportion of those that were identified by each jurisdiction as ‘at risk’. Communities that are reported as not ‘at risk’ and were not screened are not included in the calculation.
**screening coverage is based on ABS population data for communities ‘at risk’ as the denominator
3.2.2 Indices of severityAboriginal and Torres Strait Islander peoples are at an increased risk of developing avoidable blindness and vision loss and are less likely to visit eye health care practitioners than other Australians31. Blindness prevents active participation in education and limits employment opportunities. In contrast with developing countries where active trachoma and trichiasis are more common among adult women than men, Australian surveys have not identified any sex differences in active trachoma or trichiasis prevalence32.
The CDNA Guidelines for the Public Management of Trachoma in Australia33 recommend the use of the simplified trachoma grading classification developed by the WHO to diagnose trachoma, which is outlined in Table 3.2. Children screened, who present with trachoma usually have active trachoma, TF and/or TI.top of page
Table 3.2: Simplified trachoma grading classification system by WHO
Source: Figueira E (2006). Trachoma: An evidence based global and Australian perspective, The Fred Hollows Foundation.Scarring trachoma can result in corneal opacity and eventually leading to blindness without appropriate intervention, this is the most severe outcome from trachoma. According to the Trachoma Surveillance Report 200834 blinding trachoma continues to exist in many communities in Australia, however the number of affected persons was not identified. Trichiasis screening was carried out in a small number of communities and the overall prevalence in those screened was 4%. In total 52 cases of trichiasis were diagnosed. Also, of the 1,407 people screened, 49 had received surgery within 12 months to the date of reporting and virtually all (46) of these cases were in the NT35 . A more systematic approach to screening and treatment for trichiasis would provide a more comprehensive picture of the long term impact of untreated trachoma.
3.2.3 Disparities/inequities associated with trachomaThe burden of trachoma is borne by the most impoverished populations in the world, populations where poverty is coupled with unhygienic overcrowded living conditions and poor access to water and sanitation, which are linked with trachoma36. The economic impact of the disability caused by trichiasis and blindness on those who are poor contributes to keeping them in the cycle of poverty. Trachoma had disappeared from most parts of Australia by the 1930’s as housing, hygiene and living conditions improved, however these advances did not occur in many remote parts of Australia. Active trachoma in Aboriginal and Torres Strait Islander children and trichiasis in Aboriginal and Torres Strait Islander adults is still prevalent37. Australia is the only developed country still to have active trachoma.
Aboriginal and Torres Strait Islander peoples continue to experience relative disadvantage compared with non-Indigenous people and more specifically Aboriginal and Torres Strait Islander children are the most vulnerable group of children in Australia. The high rate of ill health in Indigenous Australians is linked to adverse socioeconomic conditions38. Environmental factors from cultural, socioeconomic and physical domains have also been shown to have a strong association with both disease and ill-health. For example, in 2004/05, Indigenous people with low levels of educational attainment were more likely than those who had completed year 12 to regularly smoke, to consume alcohol at high risk levels, to engage in low levels of exercise, and were less likely to eat fruit or vegetables on a daily basis39. top of page
3.2.4 Costs associated with trachomaTwo estimates of the economic cost of trachoma have been made by Frick and colleagues framed in terms of lost productivity40. The economic cost of one disabled person was calculated by multiplying the value of the disability weights by the individual economic productivity value for each country considered. The first estimate of a potential productivity loss across all countries with known or suspected blinding trachoma of US$2.9 billion was based on data for 2000 and considered only the burden caused by visual impairment41. In the second estimate it was found that the economic loss was higher at US$5.3 billion42. This estimate used the adjusted dollar value for 2003, it considered the productivity lost from blindness to be 100% (instead of 60%) and it added a 10% cost for each blind person for a carer. The investigators also examined the effect of including trichiasis and found that the lost productivity rises significantly to US$8 billion.
The studies by Frick and colleagues included the available Australian data in the calculations of economic loss, although the cost burden was estimated world-wide. The Australian estimates are not available separately. No studies specific to Australia were identified in the literature review, although it is reasonable to assume that the Australia’s share of the economic loss associated with trachoma would be higher than Australia’s share of the world-wide prevalence (due to the fact that GDP per capita in Australia is greater than for the other countries where trachoma is endemic).
3.2.5 PreventabilityTrachoma is preventable at the primary (preventing the occurrence of disease or other health-related event), secondary (early detection and intervention with the aim of reversing, halting, or at least retarding the progress of a condition) and tertiary level (minimising the effects of disease and disability among persons already ill). From the perspective of surveillance, preventability reflects the potential for effective public health intervention at any of these levels43. At the primary level, improved environmental conditions and hygiene are linked with reducing the prevalence of trachoma. At the secondary level antibiotic treatment at the individual and community level is likely to reduce the prevalence of trachoma and finally at the tertiary level surgery to treat patients presenting with trichiasis is recommended.
To eliminate trachoma by 2020, the WHO recommends the ‘SAFE’ strategy for countries implementing trachoma control programs44. The SAFE strategy is:
- Surgery for trichiasis;
- Antibiotic therapy;
- Facial cleanliness; and
- Environmental improvements.
Table 3.3: WHO SAFE strategy and evidence base
Assessment of evidence base
Source: Department of Health and Ageing (2006). Guidelines for the public health management of trachoma in Australia, Communicable Disease Network AustraliaWith respect to environmental health, trachoma is generally a disease of resource-poor rural communities. Risk factors for trachoma are things that favour the transmission ofC.Trachomatis from one person to another. Water scarcity promotes transmission because less water is available for face washing. Limited access to latrines increases faecal contamination of the environment providing breeding material for flies. Lack of or limited rubbish collection provides breeding material for flies. Crowded living conditions also promote transmission. Historical epidemiology of trachoma strongly supports the view that general improvements in hygiene can have a profound long term effect on this disease47.
3.2.6 Public interestTrachoma can significantly influence the future health and wellbeing of affected Indigenous Australians. The Australian Government, State and Territory Governments, non-government organisations, researchers and advocates have been working for many years to advance the program of trachoma control in areas of need48. Recognising disparities in population groups, the Rudd Government invested $204.3 million in the 2009-10 Budget to improve health care in Indigenous communities and help close the life expectancy gap between Indigenous and non-Indigenous Australians. Part of this new funding aims to “eliminate trachoma within a finite time frame”.
The Improving Eye and Ear Health Services for Indigenous Australians for Better Education and Employment Outcomes measure provides $58.3 million over four years to provide additional services in the management of eye and ear health problems that will support closing the gap in education and employment outcomes for Indigenous Australians. Approximately $16 million of the $58.3 million is available under the measure to improve trachoma control and surveillance in areas identified as experiencing endemic trachoma, the NT, SA and WA, and other jurisdictions if identified. This new investment will complement and build on existing trachoma control activity in jurisdictions. The measure is being administered through DoHA.
30Tellis B, Fotis K, Dunn R, Keeffe J and Taylor H (2009). Trachoma surveillance report 2008, National Trachoma Surveillance and Reporting Unit, Centre for Eye Research Australia.
32Department of Health and Ageing (2006). Guidelines for the public health management of trachoma in Australia, Communicable Disease Network Australia.
34Tellis B, Fotis K, Dunn R, Keeffe J and Taylor H (2009). Trachoma surveillance report 2008, National Trachoma Surveillance and Reporting Unit, Centre for Eye Research Australia.
36Sumamo E, Emerson P, Harvey K and Burton M (2007). The Cochrane Library and trachoma: an overview of reviews, Evidence based child health: A Cochrane review Journal; 2: 943-964.
37Mak D, O’Neill L, Herceg A and McFarlene H (2006). Prevalence and control of trachoma in Australia, 1997-2004, Communicable Disease Intelligence; 30 (2): 236-247.
38Australian Institute of Health and Welfare (2008). Australia’s Health 2008, Australia’s Health No. 11, AIHW, Canberra.
40Burton MJ and Mabey DC (2009). The global burden of trachoma: A review. PLOS Neglected Tropical Diseases, 3; 10: 1-7
41Frick KD, Basilion EV, Hanson CL, Colchero MA (2003). Estimating the burden and economic impact of trachomatous visual loss. Ophthalmic Epidemiol 10: 121–132.
42Frick KD, Hanson CL, Jacobson GA (2003). Global burden of trachoma and economics of the disease. Am J Trop Med Hyg 69: 1–10.
43Center for Disease Control (2001). Updated guidelines for evaluating public health surveillance systems: recommendations from the guidelines working group. Available from: http://www.cdc.gov/mmwr/preview/mmwrhtml/rr5013a1.htm
44Polack S, Brooker S, Kuper H, Mariotti S, Mabey D and Foster A (2005). Mapping the global distribution of trachoma, Bulletin of the World Health Organization; 80 (12)
45Sumamo E, Emerson P, Harvey K and Burton M (2007). The Cochrane Library and trachoma: an overview of reviews, Evidence based child health: A Cochrane review Journal; 2: 943-964
46Schachter J, West SK, Mabey D, Dawson CR, Bobo L, Bailey R, Vitale S, Quinn TC, Sheta A, Sallam S, Mkocha H, Mabey D, Faal H (1999). Azithromycin in control of trachoma. Lancet 354: 630–635.
47Burton MJ and Mabey DC (2009). The global burden of trachoma: A review. PLOS Neglected Tropical Diseases, 3; 10: 1-7
48A National Framework for Delivery of Trachoma Control Programs, November 2009 (unpublished, obtained from the Department of Health and Ageing)