The nematode (roundworm) Gnathostoma spinigerum and Gnathostoma hispidum, which infects vertebrate animals.  Human gnathostomiasis is due to migrating immature worms.

Risk Factors

Humans become infected by eating undercooked fish or poultry containing third-stage larvae, or reportedly by drinking water containing infective second-stage larvae in Cyclops

Symptoms

The clinical manifestations in human gnathostomiasis are caused by migration of the immature worms (L3s).  Migration in the subcutaneous tissues causes intermittent, migratory, painful, pruritic swellings (cutaneous larva migrans).  Migration to other tissues (visceral larva migrans), can result in cough, hematuria, and ocular involvement, with the most serious manifestations eosinophilic meningitis with myeloencephalitis.  High eosinophilia is present.

Diagnosis

Removal and identification of the worm is both diagnostic and therapeutic.

Treatment

Surgical removal or treatment with albendazole* or ivermectin* is recommended.

References

CDC