The intestinal protozoan Giardia was first described over 300 years ago in 1681 by Leeuwenhoek, from his own stools. In his description of Giardia, he noted the size, movement, and morphology of the organism, and associated its presence with the diarrheic nature of his stools and his dietary habits. This truly remarkable account contains the first description of Giardia in morphologic, pathogenic, and epidemiologic terms. Our knowledge of the organisms in the genus Giardia has advanced tremendously in the past two decades. With the advent of new tech- nologies, including techniques in electron microscopy, biochemistry, immunochemistry, tissue culture, and physiology, a tidal wave of information has appeared on the organization and function of this parasitic protozoan and its interaction with its host. The purpose of this book is to celebrate the tricentennial discovery of Giardia by Leeuwenhoek by presenting the above-mentioned advances in our knowledge of Giardia and giardiasis. In the first section of this book, the dominant theme is the biology of the organism and the correlation of structure-function relationships.
I. Structure and Physiology.- 1 Structure of the Trophozoite and Cyst.- 2 Trophozoite Motility and the Mechanism of Attachment.- 3 Metabolism of Trophozoites.- 4 Giardia Isozymes.- 5 Methods of Isolating Trophozoites and Cysts.- 6 In Vitro Cultivation of Giardia Trophozoites.- 7 The Role of Reducing Agents and the Physiology of Trophozoite Attachment.- 8 Models for Excystation.- II. Giardiasis.- 9 Symptomatology, Diagnosis, and Treatment.- 10 Changes in the Small Intestinal Mucosa in Giardiasis.- 11 Cellular and Humoral Immunity in Giardiasis.- 12 Human Immune Responses to Giardia lamblia.- 13 Antigenicity of Giardia lamblia and the Current Status of Serologic Diagnosis of Giardiasis.- 14 Animal Models for Giardiasis.- III. Epidemiology.- 15 Waterborne Outbreaks of Giardiasis: Current Status.- 16 Detection of Giardia Cysts in Drinking Water: State of the Art.- 17 Filtration as a Barrier to Passage of Cysts in Drinking Water.- 18 Resistance of Cysts to Disinfection Agents.- 19 Direct Fecal-Oral Transmission of Giardiasis.- 20 Evidence for Animal Reservoirs and Transmission of Giardia Infection between Animal Species.- 21 Giardia lamblia: The Transfer of Human Infections by Foods.- 22 Some Perspectives on the Transmission of Giardiasis.