Praziquantel and oltipraz: the treatment of schoolchildren infected with Schistosoma mansoni and/or Schistosoma haematobium in Gezira, Sudan.

Of 111 schoolchildren--all of whom were infected with Schistosoma mansoni and 97 of whom were also infected with S. haematobium--54 were treated with Praziquantel (2 x 20 mg kg-1) and 57 with Oltipraz (2 x 15 mg kg-1). There was no apparent difference between the efficacy of the two drugs. Follow-up studies over the following 12 months indicated that mass chemotherapy of schoolchildren can be expected to reduce the egg output of those treated by almost 100%, but that, unless there is some break in transmission, the egg output may well be as high after 12 months as it was before treatment--at least in the boys. After a round of chemotherapy, retreatment of school-aged boys in an area where transmission is heavy will be necessary six to 12 months later.