Introduction and History


Clinical Presentation in Humans

Transmission and Vector


Incubation Period and Morphology

Diagnostic Test

Management and Therapy

Epidemiology and Country Information

Public Health and Prevention Strategies

Useful Web Links



Tara Kirk Parasites and Pestilence Human Biology Stanford University

Trichostrongyliasis - Incubation Period and Morphology


Trichostrongylus life cycle. From the University of Pennsylvania School of Veterinary Medicine Parasitology Website.
(A/B) Depending on the species Thrichostrongylus settles in the stomach or small intestine.
(C) Eggs are passed into the external environment through feces. The parasite then hatches and is free living.
(D/A) Area of exsheathment in some species (D not aplicable to humans).


Incubation Period: In favorable conditions eggs hatch within 24 hours of being passed. They spend 3 to 5 days in the soil until they are ingested as stage 3 larvae. After ingestion they develop into adults in the small intestine. The females then lay eggs that are passed into the external environment.

Morphology: Adults are small and hair-like, only 5 to 10 mm long and thin. Eggs are most often 73 to 95 micrometers in length and about 40 micrometers in width. Trichostrongyliasis can be distinguished from other species through the morphology of the eggs, which are tapered at one or both ends.