Book excerpt: This book examines the two major parasite groups that are transmitted via water or foods: the single-celled protozoa, and the helminths: cestodes (tapeworms), nematodes (round worms), and trematodes (flukes). Each chapter covers the biology, mechanisms of pathogenesis, epidemiology, treatment, and inactivation of these parasites. This important new text offers a better understanding of the biology and control of parasitic infections necessary to reduce or eliminate future outbreaks in the U.S. and elsewhere.