Giardia spp.

Gerbils may harbor the protozoan Giardia.

Transmission occurs by the fecal-oral route of infective cysts.

Humans may have an asymptomatic infection or may have overt clinical signs of anorexia, nausea, abdominal cramps, bloating, and diarrhea. Severe infections may involve bile and pancreatic ducts and may damage upper intestinal mucosa.