Treatment with praziquantel of schoolchildren with concurrent Schistosoma mansoni and S. haematobium infections in Gezira, Sudan

A field trial was conducted in Sudan to evaluate the acceptability and efficacy of praziquantel given to schoolchildren aged 7-11 years who were all infected with both Schistosoma mansoni and S. haematobium. Two dosage regimes were compared: a sngle dose of 40 mg/kg body-weight, and a divided dose 2 x 20 mg/kg given 4-6 h apart. When interviewed 24 h after treatment, 80% of the children complained of drug-induced abdominal pain, diarrhoea, nausea or vomiting. However, none of the side-effects persisted beyond the day of treatment. More children complained of side-effects from the divided dose than from the single dose. The cure rate in the divided-dose group was slightly better than in the single-dose group but the differences were not significant at any follow-up, nor when results were expressed in terms of cumulative failures. The initial cure rates were 66.3% and 61.8% at 1 month, and 73.2% and 64.7% at 3 months for the divided and single doses respectively. After 12 months there had apparently been considerable reinfection with S. mansoni and 73% of the children were passing eggs. Reinfection with S. haematobium was negligible.