Shigella is a bacteria that is a major cause of diarrhoea and dysentery(diarrhoea with blood and mucus in the stools).The bacteria are transmitted by eating/drinking contaminated food or water, or through person-to-person contact. In the body, the bacteria invade and destroy the cells lining the large intestine, causing ulceration of the inner lining of the intestines and bloody diarrhoea.
Attribution: Avallain