The effects of endemic schistosomiasis and of hycanthone on the mental ability of african school children

354 primary school children aged 8 to 12 years were examined: 134 were found to have schistosomiasis. During a period of 1 year, they were tested at intervals for intellectual ability (using Raven's progressive matrices) and it was found that the infected children were significantly (P < 0·01) impaired; no significant differences in school work, growth or blood composition (including renin activity) were associated with the disease. Treatment with intramuscular hycanthone mesylate (Etrenol, Winthrop Laboratories) produced a significant (P < 0·01) increase in the Raven's score; the school work and rate of growth improved, but again, the changes were not significant (P > 0·05). 6 months after giving hycanthone 11% (10/91) of the children were passing viable ova in their urine.