Multiple choice Hydatid Cyst has _______ layers. 2 3 4 5 Reveal answer Fill a bubble to check yourself B Correct answer Explanation Hydatid disease, caused by the parasite Echinococcus granulosus, mostly affects the liver and the lungs with hydatid cysts which consist of three layers: (1) the outer pericyst; (2) the middle laminated membrane; and (3) the inner germinal layer.