Reliability of clinical diagnosis in identifying infectious trachoma in a low-prevalence area of Nepal

The WHO Alliance for Global Elimination of Trachoma by 2020 has increased t he need to identify ocular chlamydial infections by clinical examination in areas of both high and low prevalence. The relationship between clinically active trachoma las defined by clinical examination) and chlamydial infect ion is known for areas with hyperendemic trachoma, but not for areas with a low prevalence of the clinical disease. In the present study, we examined, photographed, and DNA tested the conjunctivae of children in the Surkhet d istrict of mid-western Nepal, an area known to have a low prevalence of cli nically active trachoma. Although 6% of the children aged 10 years and unde r were found to have clinically active trachoma, none were found to have ch lamydia infection by the most sensitive DNA amplification tests available. A very low prevalence of clinically active trachoma is not necessarily evid ence of the presence of chlamydial infection. Therefore, the WHO policy of not recommending an intensive trachoma control effort when the prevalence o f clinically active trachoma is less than 10% in children is appropriate fo r this area of Nepal.