Field study of different oxamniquine dose for Schistosoma mansoni in Gezira, Sudan.

Two hundred and ninety-six individuals of whom 126 were children and 170 adults with positive stool for Schistosoma mansoni were randomly given oxamniquine treatment in a dose of either 20, 40 or 60 mg/kg body wt. They were followed in the field for ova excretion at 1, 3 and 6 months for adults and at 1, 3, 6 and 8 months for children. The cure rates in adults at 6 months are 93%, 87% and 73% for the 60, 40, 20 mg/kg-1 treatments in order. For children the cure rates at 6 months are 36%, 58% and 63% and at 8 months are 16%, 21% and 26% for corresponding doses. There is no difference in egg reduction for those not cured between the three treatments at 6 months. It is concluded that oxamniquine need not be given in the previously recommended 60 mg/kg body wt. A choice between 40 and 20 mg/kg body wt is suggested with the 40 mg/kg body wt to be reserved for individuals leaving the endemic area, and the 20 mg/kg body wt for those continuing to stay there with substantial exposure for reinfection. The overall proper cure rates for children with a possible advantage of the low treatment in the long term for this age group is noted.