Schistosomiasis haematobium prevalence and risk factors in a school-age population of peri-urban Lusaka, Zambia.

Given association of the parasite Schistosoma haematobium with coastal and rural/agricultural populations, there is little documentation to date of infection patterns in today's rapidly urbanizing non-coastal regions. We conducted an observational study of 5-17-year-old school children (N = 1583) in peri-urban compounds of Lusaka, Zambia. Demographic information, medical history, physical examination findings and urinalysis results were recorded. Prevalence of schistosomiasis in the population was 20.72%. Significant risk factors for infection were male gender [odds ratio (OR) 2.42], age of 9-12 years or 13-17 years (OR 3.33 and 3.26, respectively, compared with 5-8-year-olds) and single and/or double orphan status (OR 1.43). Clinical officers detected schistosomiasis with a sensitivity of 24.70% and a specificity of 98.17% after history and physical examination. These results reveal that peri-urban populations have a significant but under-recognized vulnerability to infection, and suggest that only history and physical examination are inadequate for identifying a treatment population.