New insights regarding the biology of Giardia lamblia.

Giardia lamblia is one of the most common causes of intestinal disease in humans. To adapt to environments both inside and outside of the host's small intestine, this protozoan parasite undergoes significant developmental changes during its life cycle. In this review, we analyze and discuss the most recent findings regarding the process of Giardia trophozoites differentiation into infective cysts as well as the mechanism of antigenic variation, which allows the parasite to cause chronic and recurrent infections in susceptible individuals.