Australia Trachoma Surveillance Report 2011

Methodology

Page last updated: 09 April 2013

Each jurisdiction undertook screening and treatment for trachoma according to its respective protocols, and in the context of the national 2006 Communicable Disease Network Australia Guidelines for the public health management of trachoma in Australia, which recommend specific treatment strategies depending on the prevalence of trachoma detected through screening.

In 2006, when the National Trachoma Management Program was initiated, each jurisdiction identified at-risk communities from historical prevalence data and other knowledge. Over time, additional communities have been reclassified as being at risk. Screening for trachoma focuses on the at-risk communities, but a small number of other communities designated as not-at-risk have also been screened, generally if there is anecdotal information suggesting the presence of active trachoma.

The WHO trachoma grading criteria (Appendix 1) were used to diagnose and classify individual cases of trachoma.

Data collection forms (Appendix 2) for data collection at the community level were developed by the National Trachoma Surveillance Reference Group, based on the CDNA Guidelines. Completed forms were forwarded from the jurisdictional coordinators to the NTSRU for checking and analysis. Information provided to the NTSRU at the community level for each calendar year included:

    • Number of Aboriginal children aged 1-14 years screened for clean faces and the number with clean faces, by age group;
    • Number of Aboriginal children aged 1-14 years screened for trachoma and the number with trachoma, by age group;
    • Number of episodes of treatment for active trachoma, household contacts and other community members, by age group;
    • Number of Aboriginal adults screened for trichiasis, number with trichiasis, and the number who had surgery for trichiasis;
    • Community level implementation of WHO SAFE strategies.

Northern Territory

Trachoma screening and management in the NT was undertaken through collaboration between the Department of Health (Centre for Disease Control and Health Development) and Aboriginal community-controlled health services. Trachoma screening was incorporated into the Healthy School Age Kids (HSAK) 14 annual check and conducted by either local primary health care services or community-controlled services, with support from the Centre for Disease Control Trachoma Team. Following screening, treatment was generally undertaken by primary health care services with support from the CDC Trachoma Team when requested.

In 2011, community screening for trichiasis was initiated in a small number of communities by the CDC Trachoma Team. Some adult screening took place during community visits by the CDC Trachoma Team staff, ACCHS, or with optometrists or ophthalmologists from the Regional Eye Health Service based in Alice Springs.Top of page

South Australia

In 2011, Country Health South Australia (CHSA) was responsible for managing the South Australian trachoma screening and treatment program. CHSA contracted with local health service providers, Aboriginal community-controlled health services, the Aboriginal Health Council of South Australia and Nganampa Health Service to ensure coverage of screening services in all at-risk rural and remote areas. Additional screening activities were undertaken by the Eye Health and Chronic Disease Specialist Support Program (EH&CDSSP), coordinated by Aboriginal Health Council of South Australia and supported by the Medical Specialist Outreach Assistance Program (MSOAP) and the Office for Aboriginal and Torres Strait Islander Health, DoHA. This program provides regular visits to South Australian remote Aboriginal communities by optometrists and ophthalmologists. Trichiasis screening was undertaken opportunistically for adults by both the EH&CDSSP team and the trachoma screening service providers, and is also undertaken routinely as part of the Adult Annual Health Checks.

Western Australia

Trachoma screening and management in WA is the responsibility of Population Health Units (PHUs) in the Kimberley, Goldfields, Pilbara and Midwest Health Regions. In collaboration with the local primary health care providers, the PHUs screened communities in each region within a two week period, usually at the end of August or early September. Treatment was undertaken at the time of screening.

Trichiasis screening was undertaken in conjunction with adult influenza vaccinations. Screening the target population also occurs with the Visiting Optometrist Scheme (VOS) program in the Kimberley.

In 2011 Western Australia changed the definition of community , specifically amalgamating several previously distinct communities into one single community. This alters trends presented in this report compared to previous reports.

Data analysis

For the purpose of this report, a community is defined as a specific location where people reside and there is at least one school. Community coverage is defined as the proportion of at-risk communities screened for trachoma. Individual screening coverage is the proportion of children in the target age group in a community who were actually screened.

Population data were based, as in previous reports, on the 2006 census15. The population for communities in subsequent years were projected forward using Australian Bureau of Statistics (ABS) standard estimates of population increase (1.6%, 1.8% and 2.1% in the NT, WA and SA respectively). Population estimates based on the 2006 census do not account for policy change such as the NT Intervention, which may have resulted in unexpected population movements. Prevalence of active trachoma was calculated using the number of children screened as the denominator.

Trachoma data were analysed in the age groups 1-4, 5-9 and 10-15 years. Comparisons over time were mostly limited to the 5-9 year age group, for which screening coverage has been consistently high. Data from 2006 were excluded from assessment of time trends as collection methods in this first year differed from those subsequently adopted.

Adherence to the CDNA treatment guidelines was assessed by calculating the proportion of active cases and contacts requiring treatment that were in fact treated.

If the prevalence of trachoma exceeded thresholds specified in the CDNA guidelines, the number of individuals requiring treatment was estimated according to the treatment strategies used in each jurisdiction (see Appendix 3 for further details):
  • Targeted treatment - this is the treatment strategy used in SA and WA:
    • Estimate of treatment requirement = number of cases of trachoma detected through screening + the number of household contacts reported as requiring treatment. If the number of contacts was not reported, it was calculated as the number of children in the community aged six months to 14 years plus the average number of household contacts of cases detected at screening from communities, where this was reported.

  • Whole of community treatment - this is the treatment strategy used in the NT.
    • Estimate of treatment requirement = total population of the community from ABS projected population data.
Top of page