Efficacy of Bilhvax in Association With Praziquantel for Prevention of Clinical Recurrences of Schistosoma Haematobium

Inclusion Criteria: * Children in CI or CP classes of public schools in St Louis Region (Senegal) A male or female between, and including, 6 and 9 years of age at the time of the first vaccination Free of obvious health problems excepted schistosomiasis as established by clinical examination (W8-W1) Found positive for S. haematobium infection during the selection period (W12 à W9) : microhaematuria ≥ 2+ et Urinary Filtration, UF ≥ 50 eggs of Sh/10ml urine Written inform consent obtained from the parent or guardian of the subject (W9) and child acceptance Pretreated with 2 doses of 40mg/kg PZQ (at W9 and W8) Absence of heavy lesions of the urinary tract under echotomography (W8 et W1) Exclusion Criteria: * Absence of written inform consent or expressed refusal from the child Vaccination other than the study vaccine within 90 days preceding the first dose of study vaccine, or planned use during the study period. Chronic administration (defined as more than 14 days) of immunosuppressants or other immuno-modifying drugs, actual or since previous year. History of allergic disease or reactions likely exacerbated by any component of the vaccine Acute disease at time of enrolment Other conditions which in opinion of the PI may potentially represent a danger for the child to be enrolled.