The CDC Guidelines suggest that a surveillance system can be useful in:
- prevention and control of adverse health-related events;
- improving understanding of the public health implications of such events;
- discovering that an adverse health-related event previously thought to be unimportant is actually important; and
- development of performance measures, including health indicators, used in needs assessments and accountability systems72.
4.1.1 Active trachoma screeningThrough discussion with stakeholders, it has been determined that a key issue is whether the surveillance system should be designed to achieve precise estimates of the level of active trachoma across Australia, or whether the system should be less concerned with precision and more oriented to ensuring communities with endemic active trachoma are effectively identified and control activities are initiated. There were mixed views on this issue amongst stakeholders but there was a leaning towards a trachoma control emphasis. The evaluation team believes that, although it is important to obtain relatively precise measures of prevalence, a system designed to estimate prevalence and facilitate the control of active trachoma is more appropriate in the Australian situation.
The implications of this conclusion include that the surveillance system should place particular emphasis on regular and comprehensive screening of populations at greatest risk, that screening should be closely linked with agreed intervention strategies and that information should be collected on those strategies and their effectiveness. Achieving precise measures of prevalence across the whole Aboriginal and Torres Strait Islander population on an ongoing basis would be expensive (communities where trachoma risk is low would need to be regularly screened) and divert valuable resources away from taking action. top of page
In this context it is helpful to note that the recent National Indigenous Eye Health Survey (Taylor et al73), which used a gold standard sampling approach (random cluster sampling) to measure active trachoma prevalence across Australia, found that estimates of “the rates of trachoma reported from screening of Aboriginal school children in outback communities in the NT, SA and WA are generally similar to our findings”74. A brief examination of the data by produced by both methods reveals what appear to be significant differences in the regions covered by both methods75. Nonetheless, the finding made by the National Indigenous Eye Health Survey researchers suggests that the current surveillance system produces reasonable estimates of active trachoma prevalence in high risk populations, with some variations, while focusing on control and treatment.
However, the National Indigenous Eye Health Survey did identify some active trachoma in communities in NSW and Queensland that are not currently screened. Previously it was thought active trachoma had been eradicated in those jurisdictions. The three cases found in NSW included one in a major city location and two in an inner regional location. No cases were found in the outer regional or remote communities surveyed in NSW. All 12 of the Queensland cases were found in two communities in very remote coastal regions of the state. No cases were found in very remote inland, remote, outer regional or the major city communities surveyed in Queensland.
The survey found one case of active trachoma for a child living in a major city (estimated prevalence of 0.6%) supporting the view generally held by experts and other stakeholders that trachoma is not a significant problem in major urban settings. The study found three cases in inner regional areas (estimated prevalence of 1.1%) and two cases of a community located in outer region areas (estimated prevalence of 1.0%). In contrast, the study found six cases in remote areas (estimated prevalence of 1.9%), 33 cases in very remote coastal areas (estimated prevalence of 9.1%) and 36 cases in very remote inland areas (estimated prevalence of 9.7%). These findings strongly support the view that trachoma is principally a problem in remote and very remote locations.
Whilst it is important to consider how the surveillance system could be enhanced to estimate the prevalence of active trachoma in populations that have not yet been screened, ongoing screening for these populations is unlikely to be justified. There may be case for once-off screening in remote and very remote communities, combined with ongoing screening in communities where active trachoma is found to be a problem. The evaluation team therefore suggests that the current screening arrangements be extended to the remote and very remote communities in NSW and Queensland, at least on a once-off basis, to determine whether trachoma control and ongoing screening is required in these communities. Consistent with this finding, all remote and very remote communities in the NT, SA and WA that are not currently screened should be screened on a once-off basis.
The above suggestion is aligned with the performance indicator: ‘mapping of trachoma endemic regions’ described in the National Framework for Delivery of Trachoma Control Programs. The performance indicator has an action area: A survey of trachoma prevalence in communities with no or unreliable trachoma data (where trachoma is suspected) and provision of that data to the NTSRU. The action is supported by three performance measures:
- identification of communities where trachoma is suspected but no or unreliable data available (potentially ‘at risk’ communities);
- survey of potentially ‘at risk’ communities to identify prevalence of active trachoma within six months of identification of potential risk based on an appropriate sample; and
- survey data provided to national surveillance unit within three months of collection.
Another aspect of usefulness is to determine whether the screening processes should be standardised. Different approaches were observed in the jurisdictions with regular screening. In the NT, active trachoma screening is generally integrated with other childhood screening, but occurs at different times during the year. In WA and SA, active trachoma screening occurs separately to other screening activity. In WA, screening is coordinated through PHUs, involves PHUs and local primary health care staff, and occurs over a set two week period of time in each year. In SA screening is coordinated with outreach visits to communities by ophthalmologists and optometrists.
Standardisation across jurisdictions would be relevant if it was thought that the different screening approaches resulted in variations in the quality of measurement and control of trachoma. There are clearly significant gaps in screening and associated active trachoma control activities in SA. However, there is no evidence the very different approaches taken in WA and NT are resulting in significant variations in measurement and control of active trachoma. Attempting to standardise approaches across WA and NT is likely to be counter-productive. The evaluation team therefore believes that it is not necessary to standardise screening approaches, but rather to focus on standardising the collection of uniform data.
Findings: With respect to the active trachoma screening component of the national surveillance system the evaluation team finds:
- active trachoma screening is useful and it should continue to focus on control and treatment in addition to measuring trachoma prevalence;
- active trachoma screening activities should be extended, at least on a once off basis, to remote and very remote communities in NSW and Queensland with a decision to continue ongoing screening in these communities based on the estimated prevalence level;
- within NT, WA and SA all communities located in remote and very remote locations should be included in the screening program at least once within a five year cycle, with a decision to undertake ongoing screening based on the estimated prevalence level; and
- it is not necessary to standardise trachoma screening approaches across jurisdictions, but rather to focus on collection of common data.
4.1.2 Trachoma control activitiesThe current system is considered useful if it provides the data for assessing the effectiveness of the SAFE trachoma control activities. With respect to treatment with antibiotics, the data are somewhat incomplete. In some circumstances, antibiotic treatment is provided immediately on the identification of a child with trachoma (i.e. as part of the screening process), whereas in others it is left to the local health service to treat the child and his/her household and community contacts as appropriate. This process difference results in variation in the level of completion of the associated data collection. This problem could be overcome, in part, if outcomes could be tracked in individual communities. However stakeholders reported that the frequency of screening is often inadequate for such tracking.
The evaluation identified several problems with respect to assessing the impact of the face washing and environmental health parts of SAFE. One issue is that the collection of data on environmental conditions and facial cleanliness and interventions is not well catered for in the current system. Responses to these questions are qualitative, and information is subsequently not easily retrieved or analysed. A second issue is that data collected are not fed-back locally (at least not in a timely manner, but sometimes the information that is fed-back was found to be inadequate for local monitoring activities), therefore limiting action that could be undertaken to more effectively control trachoma. A third issue is that it is practically difficult for screening staff to collect the data, particularly on environmental conditions.
Findings: With respect to the trachoma control component of the current national surveillance system the evaluation team concludes that:
- the surveillance system data are useful but only partially effective in allowing an assessment of the impact of the SAFE trachoma control activities;
- the current surveillance system can be enhanced by:
- increasing compliance (with CDNA guidelines) with annual screening for communities where trachoma prevalence is greater than 5%;
- collecting more structured information (so that it can be coded and therefore easily extracted for reporting and evaluation purposes) on the health promotion activities initiated to target facial cleanliness and activities targeted at environmental issues;
- integration of data on trachoma screening with other national/local data available on community environmental factors, (e.g. from the Census on housing, or the ABS Community Housing and Infrastructure Needs Survey); and
- provision of timely feedback of data to staff involved in control activities locally to enable them to take action more readily.top of page
4.1.3 Trichiasis screening and treatmentThe evaluation team has found that although there is current active monitoring of trichiasis, there are some limitations in approach. The main problem is selection bias in that the measurement of trichiasis is often based on communities in which outreach ophthalmology services are provided, and it relies on people presenting to these services with eye problems. To get an accurate picture of trichiasis, a more representative approach to sampling is required. The evaluators note that in WA, trichiasis screening occurs at the time of influenza vaccination, an approach which should be considered by other jurisdictions as the immunisation is targeted to the same age group where trichiasis may be present.
There also appears to be significant gaps in information on access to surgery for trichiasis. The Guidelines for public health management of trachoma in Australia76 suggest collection of this information through waiting lists for trichiasis surgery. Consultations with stakeholders revealed that many people identified with trichiasis choose not to take up a referral to care, a fact that appears consistent with the data (low numbers of people who have had trichiasis surgery in the past 12 months are reported in WA and SA relative to the numbers identified with trichiasis77). The low surgery rate could be due to that fact that the data are not reported. Either way, the collection of data on surgery is an important part of assessing the impact of the SAFE program, and it is fair to conclude that the current approach is not effective.
Findings: With respect to the trichiasis screening and control component of the current national surveillance system the evaluation concludes that:
- the surveillance system data are useful but only partially effective in monitoring the prevalence of trichiasis;
- the trichiasis surveillance data could be enhanced by pursuing further integration of screening for trichiasis with other public and primary health activities targeting Aboriginal and Torres Strait Islander adults (particularly integrating screening with the provision of influenza vaccinations and ‘healthy adult checks’);
- better systems are required to capture trichiasis screening data, particularly where the screening is provided by primary health care providers as part of other activities (e.g. vaccinations and healthy adult checks);
- better systems are required for collecting data on referral to care and subsequent surgery following the identification of a person with trichiasis (e.g. consider collection of data directly from ophthalmologists providing the surgery);
- the development of a standalone Medicare Benefits Schedule (MBS) item number for trichiasis surgery should be investigated, thereby allowing Medicare data to be used to determine the number of adults who had surgical treatment. top of page
4.1.4 Antibiotic resistanceCommunity distribution of azithromycin has an important role to play in trachoma control. Previous studies have suggested an association between the widespread community use of antibiotics and a rise in antibiotic resistance in Streptococcus pneumonia78,79. More relevant is that it was shown by Leach et al (1997)80 that in Aboriginal communities with access to antibiotics and baseline pneumococcal resistance, a single dose of azithromycin, worryingly, leads to hugely increased colonisation with macrolide-resistant pneumococci but beneficial effects on group A streptococci81. As acute lower respiratory tract infections (caused by Streptococcus pneumonia) are one of the most common causes of death in children under five years old in developing countries82, it is considered important that the impact of community-wide azithromycin treatment on antibiotic resistance be evaluated.
The current antibiotic resistance surveillance system relies on data from only three laboratories, NTGPS, IMVS and WDP. It produces data that are comparable with the most recently published AGAR data (in terms of the prevalence of antibiotic resistance), however, there is no way of knowing the extent to which the data are representative of Aboriginal communities that are provided with azithromycin for the purposes of trachoma control. A brief examination of the locations of the pathology services from which data are obtained suggests that while IMVS in SA, and NTGPS and WDP in the NT, may provide adequate coverage, WDP alone will not generate representative data for WA. Consequently, the evaluation team suggests that the option of obtaining data from PathWest be further pursued (we understand that past approaches have been made but there have been un-resolved issues).
For this reason, the evaluators believe that the current approach to monitoring antibiotic resistance as part of the national trachoma surveillance system is inadequate. Discussions with stakeholders support the view that the current approach has shortcomings. They stated that the current system is relatively simple to administer and it provides a useful indicator of the potential build up of antibiotic resistance in the targeted communities. However, there were concerns that outside of the Northern Territory, Indigenous identifiers were lacking or unreliable in laboratory data. This problem is currently overcome by the use of geographic location data to pinpoint specific communities, which, given the likelihood that a person residing in those communities is Aboriginal is extremely high, is considered to provide a useful measure. However, the inadequate coverage problem is more difficult. It is our view that the NTSRU should pursue the data from PathWest in an attempt to resolve this problem.
Findings: With respect to the antibiotic resistance component of the current national surveillance system the evaluation concludes that:
- the surveillance system data are useful but only partially effective in monitoring resistance to azithromycin;
- due to the complexity and probable cost of putting in place alternative arrangements, it is considered the current approach to monitoring antibiotic resistance should be retained; and
- the current system can be enhanced by pursuing the involvement of PathWest in monitoring resistance to azithromycin.
4.1.5 Community/patient satisfaction dataThe Guidelines for public health management of trachoma in Australia suggest collection of data in relation to community/patient satisfaction with trachoma control activities. The evaluation found that community/patient satisfaction data are not reported through the current system, but may be done periodically as a separate process. Anecdotally, stakeholders reported that the level of community satisfaction with trachoma screening and control activities is high (not as threatening as screening for some other conditions), although there were still some regions where consent was difficult to obtain. The evaluators believe that the collection of data on community/patient satisfaction should be considered as part of any program evaluation that might be commissioned rather than as part of the surveillance system.
Findings: With respect to the community/patient satisfaction component of the current national surveillance system the evaluation concludes that:
- there is no routine reporting of community/patient satisfaction data in the current national surveillance system; and
- the collection of data on community/patient satisfaction should be considered as part of any program evaluation that might be commissioned rather than as part of the surveillance system and the CDNA Guidelines should be modified to that effect.top of page
72Centers for Disease Control and Prevention. 2001 Updated guidelines for evaluating public health surveillance systems: recommendations from the guidelines working group. Morbidity and Mortality Weekly Report 50(RR-13)
73Taylor HR, Fox SS, Xie J, Dunn RA, Arnold AL, Keeffe JE (2010) The prevalence of trachoma in Australia: the National Indigenous Eye Health Survey. Med J Aust, 92(5):248-53.
75Tellis 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
76Department of Health and Ageing (2006). Guidelines for the public health management of trachoma in Australia, Communicable Disease Network Australia
77Tellis 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
78Arason, V. A., K. G. Kristinsson, J. A. Sigurdsson, G. Stefansdottir, S. Molstad, and S. Gudmundsson (1996). Do antimicrobials increase the carriage rate of penicillin-resistant pneumococci in children? Cross sectional prevalence study. Br. Med. J. 313:387–391
79Pedersen, G., H. C. Schonheyder, F. H. Steffensen, and H. T. Sorensen (1999). Risk of resistance related to antibiotic use before admission in patients with community-acquired bacteraemia. J. Antimicrob. Chemother. 43:119–126.
80Leach, A. J., T. M. Shelby-James, M. Mayo, M. Gratten, A. C. Laming, B. J. Currie, and J. D. Mathews (1997). A prospective study of the impact of community-based azithromycin treatment of trachoma on carriage and resistance of Streptococcus pneumoniae. Clin. Infect. Dis. 24:356–362.
81Shelby-James, T. M., Leach, A. J., Carapetis, J. R., Currie, B. J. & Mathews, J. D. (2002). Impact of single dose azithromycin on group A streptococci in the upper respiratory tract and skin of Aboriginal children. Paediatric Infectious Disease Journal 21, 375 - 380.
82Greenwood, B. M. (1999). The epidemiology of pneumococcal infection in children in the developing world. Phil. Trans. R. Soc. Lond. B 354:777–785.
83Department of Health and Ageing (2006). Guidelines for the public health management of trachoma in Australia, Communicable Disease Network Australia