Trachoma, eye damage resulting from Chlamydia trachomatis infection, is a major cause of blindness across the world. Although the condition can be cured by a single dose of antibiotics, identifying who should be treated has been difficult. Now, a team headed by Professor David Mabey (London School of Hygiene and Tropical Medicine) and Dr Helen Lee (University of Cambridge) has evaluated a cheap, simple and quick diagnostic dipstick for C. trachomatis, developed by Dr Lee and colleagues. Following successful trials, the test is being fine-tuned for use in areas of different trachoma prevalence.

In eradication campaigns, whole communities must be treated for trachoma because it is spread extremely easily. Currently, clinical signs are used to diagnose trachoma, so treatment can be targeted effectively – but clinical observation is not an accurate guide to infection.

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Dr Lee's laboratory has developed technologies that have been used in a new generation of robust and simple diagnostic tests for a range of infections. Teaming up with Professor Mabey, the group has evaluated a test for trachoma. A trial in Tanzania (where trachoma is rife) showed that the dipstick was more than twice as good as clinical signs at predicting trachoma cases, identifying over 97 per cent of cases correctly. The work was captured in a BBC documentary aired in more than 100 countries.

In new research funded by the Wellcome Trust, the team will test the effectiveness of the dipstick in The Gambia, Senegal and Ethiopia (areas with high, medium and low levels of trachoma, respectively). In addition to evaluating its performance in the field, they will use mathematical modelling to determine the most cost-effective strategies for using the dipstick to identify communities needing treatment.

External links

• Michel CE et al. Field evaluation of a rapid point-of-care assay for targeting antibiotic treatment for trachoma control: a comparative study. Lancet 2006;367(9522):1585–90.