Index of potential contamination of urogenital schistosomiasis based on mass drug administration of praziquantel among school children in Benue State, Nigeria

Mass drug administration (MDA) of praziquantel is an intervention used in the treatment and prevention of schistosomiasis. Its effectiveness and sustainability require identifying subpopulations that are at risk of infection. A longitudinal survey was conducted among 3,810 subjects aged 5-19 years old recruited at baseline across ten council wards in Katsina Ala, Benue, Nigeria, to determine the prevalence, intensity, and index of potential contamination of urogenital schistosomiasis for three successive phases: three months, six months, and nine months post-treatment periods. Urine samples were processed using microscopy and reagent strips (Medi Test Combi 9). Prevalence of infection was recorded in all the phases of the surveys, with the first having the highest prevalence (12.30%), followed by the third phase (9.12%) and the second phase (7.60%), the difference being significant (P < 0.05). The highest intensity of infection (16 ova/10 ml urine) was observed in the first phase, followed by the third phase (15.10 ova/10 ml urine) and the second phase (11 ova/10 ml urine). Peak prevalence, intensity, and relative index of potential contamination (Rel. IPC) occurred among pupils between the ages of 10 and 14 years old in both sexes. The result of the relative contribution of each age group in polluting the snail habitat with Schistosoma eggs, thus enabling transmission, showed to a greater extent that children aged 10-14 years old were responsible for contaminating the environment with a bulk of S. haematobium eggs and for the transmission and maintenance of the disease in the area.