The infective stage for Strongyloides stercoralis is the

The infective stage for Strongyloides stercoralis is the

• A. Oocysts
• B. Rhabditiform larvae
• C. Filariform larvae
• D. Adults

Answer: (C)

The infective form is the filariform larva (the third-stage larva). In Strongyloides stercoralis, rhabditiform larvae in stool molt into this filariform form, which is capable of penetrating human skin and initiating infection. From skin, the larvae migrate through the body to the small intestine, where they develop into adults. Autoinfection can occur when filariform larvae form inside the host and reinvade. Rhabditiform larvae are the noninfective precursors, and adults are the mature intestinal stage, not the initiating form. Oocysts are not part of this parasite’s life cycle.

The infective form is the filariform larva (the third-stage larva). In Strongyloides stercoralis, rhabditiform larvae in stool molt into this filariform form, which is capable of penetrating human skin and initiating infection. From skin, the larvae migrate through the body to the small intestine, where they develop into adults. Autoinfection can occur when filariform larvae form inside the host and reinvade. Rhabditiform larvae are the noninfective precursors, and adults are the mature intestinal stage, not the initiating form. Oocysts are not part of this parasite’s life cycle.