Diarrhea Home > Giardia Lamblia Life Cycle
The Giardia lamblia life cycle begins when cysts, the resistant forms of the parasite responsible for transmitting the diarrheal illness known as giardiasis, are accidentally ingested.
Once the parasite is in the small intestine, the Giardia lamblia life cycle continues as it releases trophozoites (protozoan in the active stage of its life cycle) that multiply and remain in the intestine. As the trophozoites mature in the intestine, they simultaneously migrate toward the colon, where they become thick-walled cysts again.
Giardia lamblia is often found in:
- Surfaces that have been contaminated with feces from infected humans or animals.
The Giardia lamblia life cycle can only be continued through ingestion of the parasite; you cannot become infected with Giardia lamblia through contact with blood.
(Click Giardia Lamblia for more information about the Giardia lamblia life cycle and to see a detailed diagram of how the life cycle works.)