Australian Trachoma Surveillance Report 2013

Discussion

Page last updated: 2015

Screening coverage

Screening coverage was measured as both the proportion of at-risk communities screened and the proportion of 5-9-year-old children screened in at-risk communities, predominantly through primary school-based initiatives. Screening of older (10-14 years) and younger (0-4 years) children also takes place, but less consistently, and in 2013 all regions chose to focus screening exercises solely on the 5-9-year age group. In 2013, population estimates provided by jurisdictions were used to calculate proportions. The manner in which the populations were calculated differed among jurisdictions, with some jurisdictions using school enrolment lists, Health Information population lists, or a combination of both and local knowledge, or from the 2011 Australian Bureau of Statistics (ABS) census. In 2013, all regions increased trachoma screening coverage of 5-9-year-old children in communities that were screened except East Arnhem region in the NT and APY Lands region in SA, compared to 2012. A higher screening coverage provides confidence that those screened are representative of the community at risk, and results are therefore a more accurate reflection of the prevalence of disease within the community.

The number of at-risk communities screened has plateaued in the NT, decreased slightly in WA and decreased substantially in SA. Figure 1.8 illustrates that some communities in all jurisdictions will not be considered at risk from 2014. It is expected that this decreasing trend will continue in future years. A number of communities screened for the first time in 2013 did not have trachoma, and therefore do not qualify as being at risk for future years.

The Guidelines for the public health management of trachoma in Australia has recently undergone a review and has been revised.(reference 1 and 2). The new guidelines will direct communities to focus resources on treatment without annual screening where trachoma prevalence is already well established. Communities with non-endemic levels of trachoma will not be required to screen annually. These guidelines have been implemented in the NT in 2013, and will be implemented nationwide in 2014. This strategy has affected the number of communities screened in the NT and will have a similar effect in other jurisdictions in future years. Community and child population screening coverage have been used as an indication of the level of program delivery in previous annual trachoma reports. In response to the revised guidelines, the annual report has shifted focus from screening coverage to the extent of implementation of the guidelines with respect to screening, treatment and health promotion activities.Top of page

Trachoma prevalence

Endemic trachoma is defined by WHO as a prevalence of active trachoma of 5% or greater in children aged 1-9 years. In past years, the National Trachoma Surveillance and Reporting Unit (NTSRU) had been able to estimate the prevalence using population weights. Due to the poor screening coverage of the 0-4-year age group, it was considered that the results reported were not representative of that age group. In Australia, the prevalence in the 5-9-year age group is accepted as a sufficient measure of the prevalence of trachoma within at-risk communities.

Across all four jurisdictions in 2013, the prevalence of trachoma in 5-9-year-old children was 4%, which includes data projected forward in communities that did not screen due to implementation of the revised guidelines in the NT (see methodology, data analysis). This rate is consistent with the 2012 national prevalence of trachoma in 5-9-year old children of 4%. The observed trachoma prevalence in communities that were screened in 2013 was 3%. At a regional level in 2013, the prevalence of trachoma in children aged 5-9 years ranged from 0.3% in Western NSW to 11% in the APY Lands SA.

NSW detected trachoma in one of the ten communities screened. This community is now considered at risk and will continue to be monitored.

Trachoma prevalence in 2013 has slightly increased in SA and the NT but plateaued in WA, after a decreasing trend from 2009 to 2012 in all jurisdictions. Increasing and plateauing trends are most likely due to the decrease in at-risk communities in SA and WA. This trend may continue in future years due to implementation of the revised guidelines where communities not at risk cease undergoing screening and the at-risk population becomes more concentrated.

The target set by WHO for the elimination of blinding trachoma is defined as a community prevalence of trachoma in children aged 1-9 years of less than 5% over a period of 5 years; in Australia, the Communicable Diseases Network Australia (CDNA) target is defined as a community prevalence in children aged 5-9 years of less than 5% over a period of 5 years. Several communities designated as at risk have reported a prevalence of less than 5% over the past 5 years, or have a baseline prevalence of 0% and are therefore designated not at risk. The NTSRU will be working closely with jurisdictions to appropriately designate at-risk status for communities for future program delivery.Top of page

Trachoma treatment

The 2006 CDNA guidelines recommend the treatment of active cases and their household contacts. When prevalence is greater than 10% and cases are not clustered within a few households, community-wide treatment is suggested. This treatment approach was adopted by SA and WA. The 2014 revised CDNA guidelines recommend treatment to all people living in households with children younger than 15 years of age annually for a period of 3 years, when the community prevalence is greater than 5%, and cases are not clustered within a few households. The guidelines also recommend 6-monthly treatments over a period of 3 years for all people living in households with children younger than 15 years of age in hyperendemic communities with a prevalence of at least 20%. This approach was implemented in the NT in 2013.

Nationally, 99% of active cases that were identified in 2013 were treated for trachoma. Contact and community-treatment coverage was 81%. Total doses of azithromycin administered in 74 communities was 10 219. The majority of these were in the NT.

Trichiasis

Previous annual trachoma reports have reported on trichiasis screening coverage. The previous at-risk population was estimated using the current year’s trachoma at-risk community adult population, which does not account for changing endemic areas that have occurred over time, and transiency into non-endemic regions. It was therefore decided that estimating an at-risk population for trichiasis is not feasible.

The number of adults aged 40 years and older screened for trichiasis decreased in 2013 with 3,856 screened in 2013, and 4,468 screened in 2012. Some regions also reported screening undertaken in adults aged older than 15 - 30 years.

Of the adults aged older than 40 years who were screened, 1% (49/3,856) prevalence levels of trichiasis were reported.

In 2013, 31 cases of trichiasis surgery were reported in NT (23), SA (2) and WA (6). These cases may have been identified from previous years screening activities. The reporting of trichiasis data regarding referral and surgery undertaken is limited due to incomplete data collection and compilation.Top of page

Facial cleanliness

Promoting facial cleanliness is a major component of the SAFE strategy, recognising that the presence of nasal and ocular discharge is significantly associated with the risk for both acquiring and transmitting trachoma. The proportion of 5-9-year-old children screened who had clean faces increased slightly in the NT, and decreased slightly in SA and WA. NSW had the highest prevalence of facial cleanliness at 96% of all children screened. The NT did not report levels of facial cleanliness in communities that did not screen for trachoma due to implementation of the revised guidelines. It is recommended that jurisdictions implementing the new guidelines continue to screen for facial cleanliness in communities where treatment and health promotion activities are undertaken.

Program delivery and monitoring

Improvements in program delivery have been reported in 2013 with increased coverage of screening and treatment delivery and health promotion activities in WA. However, although treatment coverage in the NT and SA were high, these jurisdictions did not reach their community screening goals due to funding issues with service providers. Data quality also improved in all jurisdictions; however, as many regions chose to focus on the 5-9-year age group, data pertaining to the 0-4 and 10-14-year age groups were not comprehensive.

The newly endorsed CDNA guidelines will strengthen trachoma control programs in all jurisdictions by reducing ambiguity experienced in previous guidelines and provide clear guidance on screening and treatment methods. The impact of the new strategies, in particular treatment and screening schedules, may not be evident for several years.

Progress towards Australia’s elimination target

The Australian government’s commitment to the WHO Alliance of the Global Elimination of Blinding Trachoma by the year 2020 (GET 2020), of which Australia is a signatory, continues with further funding committed to ensuring that trachoma programs are increased and strengthened.

Discussions and plans are required for the next phase of monitoring communities no longer considered at risk, and planning for monitoring trichiasis once blinding trachoma has been eliminated from Australia.

With the implementation of new guidelines in 2014 and improved efforts, as reported in 2013, and decreasing numbers of at-risk communities leading to a greater target on focused endemic areas, Australia will stay on track to eliminate trachoma by 2020.Top of page