Strongyloses ratti and S. stercoralis: effects of cambendazole, thiabendazole and mebendazole in vitro

Abstract

The effects of in vitro incubation of three henzimidazole anthelmintics, thia bendazole, mebendazole and cambendazole on Strongyloides were compared. No drug affected hatching of S. ratti eggs or the viability of infective larvae or para sitic adult worms, but all three inhibited moulting of S. ratti larvae. In addition, cambendazole, but not thiabendazole or mebendazole, impaired the viability of S. ratti first-and second-stage larvae. The three drugs had no effect on isolated S. stercorais free-living adult worms, but they all prevented development of S. ster¬ coralis rhabditiform larvae. Thiabendazole and mebendazole had no effect on the infectivity of either S. ratti or S. stercoralis infective larvae, but infection with these worms was abrogated by prior incubation with cambendazole. These results indicate that cambendazole acts in a different manner to the other two drugs. Since it is active against larvae migrating through the tissues, it is potentially of much greater value than thiabendazole or mebendazole in the therapy of stron¬ gyloidiasis.

Dissociation of the protective immune response in the mouse to Strongyloides ratti

“…Likewise, thiabendazole has no effect on larvae migrating through the tissues of dogs infected with S. stercoralis . Since cambendazole does prevent maturation of infective larvae of both 5. ratti (GROVE, 1982;GROVE & NORTHERN, 1986) and 5. stercoralis (GROVE & NORTHERN, 1988), we examined the effects of treatment with both of these agents on the development of protective immunity. Treatment with cambendazole on the first day after infection allows sufficient exposure to generate immunity as indicated by serological studies NORTHERN et al, 1989) and by the generation of resistance to adult worms-if administration had been left to 2 to 3 days after infection, some parasites would have reached the gut (GROVE, 1982) thus invalidating the experiment.…”