Effect of mefloquine on worm burden and tegumental changes in experimental Schistosoma mansoni infection

There is an important need to develop alternative anti-schistosomal drugs, as current treatment depends mainly on praziquantel (PZQ). This work aimed to study the in vivo effect of mefloquine on worm burden and tegumental changes on both the juvenile and adult worms in experimental Schistosoma mansoni infection. We studied the effect of this compound in mice infected with cercaria of Schistosoma manson then treated with a single oral dose of 400mg/kg mefloquine, 3 and 7 weeks after infection and worms were recovered two, three and seven days following treatment. Worm burden was calculated and alterations on the tegumental surface of schistosomula were examined by electron microscopy. The total worm burden reduction in juvenile was 94.5% and in adults was 74.8%. The electron microscopy examination showed tegumental changes in the form of retracted ventral sucker and oral sucker, fusion of tegumental ridges, pitting of the tegument and corrugations with swelling of the tegument in parts and shrinkage in the other parts with formation of deep furrows, disruption and peeling of the tegument with loss of spines and blebbing. Mefloquine has a promising effect in treatment of schistosomiasis.