Giardiasis is a parasitic disease caused by the protist enteropathogen Giardia duodenalis, especially common in children and travelers. Infected individuals experience steatorrhea, a type of diarrhea with fatty sticky stool; abdominal pain, weight loss, and weakness due to dehydration and malabsorption. Less common symptoms include skin rash, hives and joint swelling. Symptoms usually begin one to three weeks after exposure and, without treatment, may last two to six weeks or longer. Some infected individuals experience mild or no symptoms and remain symptom-free even if the infection persists for a long time.