The use of photography and image grading to future-proof trachoma surveys

03 Mar 2022
Classroom learning for TT-only surveys and use of 3d images. Photo credit: Alfa Amadou, Benin.

A new report on the use of photography to support trachoma grading has been published by the International Coalition for Trachoma Control, summarizing the results of discussions and proposed next steps from two workshops held in 2021.

The aims of the workshops were to 1) review existing data and experiences with using photography and image grading for trachoma and other eye health problems; 2) to assess opportunities and challenges to use them to train trachoma graders, for supervision and quality assurance, and to replace field grading in surveys; and 3) identify priority operational research questions whose results are critical for moving the work forward.

The workshops were held following the growing recognition that as countries are moving towards the elimination of trachoma as a public health problem, and trachoma prevalence declines in districts and countries, it is becoming increasingly difficult to train new field graders and to recertify existing graders with live participants to carry out population-based surveys.

It has been proposed that the use of photography and image grading could potentially overcome these challenges in the future. Photographs could be used more extensively within trainings and as part of supervision during surveys. Furthermore, the use of photography and image grading as a replacement for TF grading in the field has been proposed, as has been done in numerous research projects and clinical trials. However, there is a lack of standardization and validated protocols outside of research projects for the use of photographs to train graders, to assess quality of field grades, and to serve as an adjunct to, or substitute for, field grading.

It is harder to find sufficient numbers of trachomatous inflammation—follicular (TF) cases, forcing trainees to travel further in-country, or even to other, more endemic, countries. This makes grader training and certification, in the short-term, more difficult, expensive, and time-consuming. In the long-term, it will no longer be possible to depend on live TF cases to train and certify graders.

In addition, regardless of TF prevalence, there are other situations where the use of trained graders may not be ideal or sustainable: these include areas with limited numbers of graders and high attrition, such as the Americas; conflict zones that need surveys where graders may not be allowed in; and hard to reach areas.

Report writers have invited the trachoma community  to engage in this effort by contributing and working together to implement the proposed next steps and accelerate the implementation of operational research priorities. In this way, we will be able to close knowledge gaps and produce the evidence needed to use photography and image grading to future-proof trachoma surveys.

Access the report here.