Clinical and Microbiological Assessment of Trachoma in the Kolofata Health District, Far North Region, Cameroon

BACKGROUND AND AIMS Trachoma is a sight-threatening process triggered by the infection of the conjunctiva with Chlamydiae. Blindness associated with trachoma was reported in Sahelian areas of Cameroon. However, data on the prevalence of this neglected infection in the Far North Region are not available. The aim of this study was a) to assess clinical trachoma and b) to detect Chlamydia in the conjunctiva of trachomatous populations living in the Far North Regions of Cameroon. METHODS A total of 2,423 randomly selected children (1-10 years) and 1,590 women over 14 from randomly selected villages from the Kolofata Health District (115,000 inhabitants) were included in a cross-sectional study in February 2009. Trained staff examined and obtained conjunctival swabs from trachomatous subjects. DNA was extracted and amplified to detect Chlamydia DNA by real-time PCR. The quality of sampling was assessed by quantifying the number of epithelial cells. RESULTS Children (2,397 or 98.9% of the predicted number) and women (1,543; 97.0%) were examined. The prevalence of follicular trachoma (TF) in children was 21% (95% CI 17.8-24.5) and of intense inflammatory trachoma (TI) 5.2% (95% CI 3.6-7.3). Among the women, trichiasis (TT) was observed in 3.4% (95% CI 2.4-4.7), corneal opacities (CO) in 1.4% (95% CI 0.8-2.3) and trachoma-related blindness in 0.9% (95% CI 0.4-1.8). Conditions related to income, illiteracy, latrines, water supply and animals wandering close to dwellings were similar in all the villages. PCR was positive in 35% of children with active trachoma and in 6% of adult females presenting TT and/or related corneal opacities. CONCLUSION The prevalence of trachoma and the severe trachoma sequelae found during this survey underline the urgent need to implement efficient blindness prevention interventions to improve the visual future of the people in the Sahelian region.