Of 433 schistosomiasis mansoni patients in St. Lucia who were treated with hycanthone (3 mg/kg of body weight), 190 were seen 2 years after treatment and 143 of these had attended all follow-up examinations at 6 weeks, 6 months, 1 year, and 2 years. Viable eggs were not detected in 86% at 1 year nor in 76% at 2 years. The reinfection rate, as judged by a significant increase in egg excretion, was 15% and was related to the geographic area to which the patient returned. Extremely high total reduction in egg excretion (98%) was achieved through 1 year, and even with reinfections this fell only to 87% at 2 years. Liver and spleen enlargement was related to intensity of infection and responded to treatment in 92% and 83% of instances, respectively. Among patients with hepatosplenomegaly, those 15 years or older showed less clinical response than younger patients but were too few for statistical comparison.
Staff member, The Rockefeller Foundation.
External staff, British Medical Research Council; seconded to The Rockefeller Foundation.