Giardiasis is an infection in the small intestine that is caused by Gardias. Giardia lamblia is a microscopic parasite that lives inside animals, including domestic, and in some people.
1. Usually people got infected with Gardias as a result of the contact with the infected people and unclean fluids and substances, including water and food – and that is what makes this disease popular for overpopulated developing countries. But you still can get infected.