Assessing the Prevalence of Trachoma: Lessons from Community Screening with Laboratory Testing in Australia’s Torres Strait Islands

ABSTRACT

Purpose

We undertook a screening program between 2016 and 2019 to determine if trachoma was endemic in the Torres Strait Islands of Queensland, Australia.

Methods

Eleven screening surveys assessing trachoma prevalence were undertaken in seven communities using the World Health Organization (WHO) simplified grading tool. Additionally, an ophthalmologist performed a detailed clinical assessment including examination for Herbert’s pits and corneal pannus and, where clinically indicated, collection of conjunctival specimens to investigate the presence of Chlamydia trachomatis nucleic acid.

Results

Prevalence of trachomatous inflammation—follicular (TF) in children aged 5–9 years for the aggregated first survey across all communities was 6% (17/284). No child had trachomatous inflammation—intense, trachomatous scarring, corneal pannus, or Herbert’s pits. Of the 66 times any child was tested for C. trachomatis by polymerase chain reaction (PCR), the result was negative. No cicatricial trachoma was identified amongst the adults (n = 186) who were opportunistically offered examination.

Conclusion

Whilst TF was present, the lack of intense inflammatory thickening in any child examined, the lack of end-stage trachomatous disease, and the lack of ocular C. trachomatis detection by PCR indicate trachoma is not endemic in the Torres Strait Islands, and no ongoing public health intervention is required. These findings add to a growing body of evidence suggesting that use of the WHO simplified grading tool alone in the peri-elimination setting may overestimate the community burden of trachoma.

KEYWORDS:

• Trachoma
• ocular chlamydia trachomatis
• chlamydial conjunctivitis
• queensland
• neglected tropical disease

Acknowledgments

We thank the residents of the Torres Strait Islands for their involvement in the project. We also thank the Torres Strait Island Regional Council, the Native Title Prescribed Body Corporate, the Torres and Cape Hospital and Health Service, Pathology Queensland, the Queensland Paediatric Infectious Diseases Laboratory, and Tagai State College for supporting the screening activities reported here.

Disclosure statement

The authors report there are no competing interests to declare.

Supplementary material

Supplemental data for this article can be accessed online at https://doi.org/10.1080/09286586.2022.2136389

Additional information

Funding

This work was performed in conjunction with public health trachoma screening activities in Queensland, with funding support from Queensland Health and the Australian Department of Health under the Project Agreement on Improving Trachoma Control Services for Indigenous Australians. LJW is supported by a National Health and Medical Research Council EL2 Investigator grant (#2009380)