Schistosoma mansoni: evaluation of the activity of oxamniquine on schistosomules, at 24 hours after infection

Abstract

Mice transcutaneously infected with about 400 cercariae were submitted to treatment with oxamniquine (400 mg/kg), 24 hours after infection. The recovery of schistosomules, at 4, 24, 48 and 72 hours and 35 days after treatment, showed the activity of the drug on the parasites, thus practically preventing their migration from the skin to the lungs. Worm recovery performed in the lungs (96 hours after treatment) showed recovery means of 0.6 worms/mouse in the treated group and 53.8 in the control group (untreated). The perfusion of the portal system carried out at 35 days after treatment clearly showed the elimination of all the parasites in the treated group, whereas a recovery mean of 144.7 worms/mouse was detected in the control group (untreated). These findings confirm the efficacy of oxamniquine at the skin phase of infection, and also show similarity with the immunization method that uses irradiated cercariae. The practical application of these findings in the medical clinic is discussed too

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

“…Second, oxamniquine in contrast to praziquantel seems to be able to affect immature stages of S. mansoni. 25 Differences in host immune response or host behavior could also account for differences in apparent drug efficacy. The only immunologic markers tested (immunoglobulins and TNF␣) did not show any differences between outcome groups.…”