Trachoma among children in community surveys from four African countries and implications of using school surveys for evaluating prevalence
Background School surveys provide a convenient platform to obtain large child cohorts from multiple communities and are widely used as a proxy to determine community prevalence of neglected tropical diseases. The purpose of this study was to compare trachoma prevalence between preschool- and school-aged children and children who attend and do not attend school.
Methods We analysed data from community-based trachoma surveys conducted from 2008–2011 in Ethiopia, Mali, Niger and Nigeria. The surveys utilised a cross-sectional, randomised cluster design. Individual-level data on school attendance was collected.
Results Overall, 75 864 children aged 1-15 years from 2100 communities were included in the analysis. The prevalence of trachomatous inflammation follicular (TF) among these children in surveyed districts was 19.1% (95% CI 17.9–20.2%) in Ethiopia, 6.2% (95% CI 5.4–6.9%) in Niger, 4.6% (95% CI 4.2–4.9%) in Mali and 4.2% (95% CI 3.5–4.9%) in Nigeria. Controlling for age, sex and clustering, the OR of TF for school-attendees compared to non-attendees was 0.64 (95% CI 0.56–0.73) in Ethiopia, 0.67 (95% CI 0.56–0.80) in Mali, 1.03 (95% CI 0.81–1.16) in Niger and 1.06, (95% CI 0.65–1.73) in Nigeria.
Conclusion Estimating the prevalence of trachoma through examination of only school-going children risks underestimating the true prevalence.
King, JD., Odermatt, P., Utzinger, J., Ngondi, J., Bamani, S., Kamissoko, Y., ... Emerson, PM. (2013). Trachoma among children in community surveys from four African countries and implications of using school surveys for evaluating prevalence. International Health, 5(4), 280-287. DOI: 10.1093/inthealth/iht027