Field trials of praziquantel and oxamniquine for the treatment of schistosomiasis mansoni in Burundi

Abstract

Praziquantel and oxamniquine were evaluated under operational conditions for use in mass-treatment campaigns in the Rusizi Plain, Burundi. After 6 weeks, the cure rates for oxamniquine at 20, 30 and 40 mg/kg in children (less than 20 years) were respectively 47%, 67% and 86%; in adults they were 86%, 97% and 97%. The egg reduction rates were over 98% in all groups. For praziquantel at 20, 30 and 40 mg/kg the cure rates in children were respectively 58%, 63% and 78%; in adults, 55%, 87% and 91%. The egg reduction rates were respectively 92%, 96%, 98% and 91%, 98%, 98%. These results were largely confirmed by a follow-up 3 months after treatment. Oxamniquine frequently caused important dizziness and drowsiness, and in 2 cases epileptiform seizures. The side effects of praziquantel were mainly mild transient colics and diarrhoea. The cost of oxamniquine (in Burundi) was twice to three times the cost of praziquantel. Because of its better acceptability and its lower cost, with only slightly less good parasitological results, praziquantel, at 40 mg/kg in a single dose, has been selected as the drug of choice for mass-treatment campaigns in Burundi.

Biochemical and Immunologic Predictors of Efficacy of Treatment or Reinfection Risk for Schistosoma Mansoni

“…The two drugs most recently used in the treatment of Schistosoma mansoni, oxamniquine and praziquantel, have similar profiles for efficacy as single-dose therapies. 1 A consistent finding for both is that 10-20% of those treated fail to clear their infection, although nearly 100% experience a reduction in the intensity of infection. 1,2 The factors associated with this fairly constant level of treatment "failure" have been primarily associated with very heavy infection and intense transmission, 3,4 as well as some level of noncompliance with taking these drugs.…”

“…1 A consistent finding for both is that 10-20% of those treated fail to clear their infection, although nearly 100% experience a reduction in the intensity of infection. 1,2 The factors associated with this fairly constant level of treatment "failure" have been primarily associated with very heavy infection and intense transmission, 3,4 as well as some level of noncompliance with taking these drugs. Because the drug does not affect immature stages of the parasite, drug efficacy may seem to be lower where many individuals have experienced a new infection within 4-6 weeks of treatment.…”

Drug Resistance in Human Helminths: Current Situation and Lessons from Livestock

“…In the field, particularly in community treatment, the usual dosage is 40 mg/kg of body weight in a single dose; higher dosages or split regimens result in lower compliance (89). In hospitalized patients, particularly for S. japonicum and S. mekongi, and for heavy infections with the other species, the recommended dose is 30 mg/kg, up to (32,71,89). In endemic conditions, reinfection is the rule rather than the exception, particularly in children, who are heavily exposed and appear to be (innately or immunologically) more susceptible to infection than adults (72).…”

“…Oxamniquine, used at a dosage of 15 to 40 mg/kg, is active only against S. mansoni, with CR (Ͼ80%) and ERR (Ͼ95%) usually somewhat higher than with PZQ (71,155). Although by and large a safe drug, oxamniquine may have troublesome side effects in some individuals, such as drowsiness, severe dizziness, and seizures.…”

Clinical investigation of a population recently infected with Schistosoma mansoni (Richard‐Toll, Senegal)

“…Prior evidence that this dose would be nearly as effective as the usual 4 0 mg/kg (Gryseels et al 1987, Polderman et al 1988 and would cause fewer sideeffects (Katz et al 1979) supported this choice.…”