I became intrigued with parasites when I started my research career as a graduate student in England. I was rightly told that the field of parasites has a great future for a starting biochemist/pharmacologist. The field of parasite research was not crowded and therefore was designated as a neglected area of research. Subsequently, a large number of talented and highly sophisticated young scientists were attracted by the urgent need for modern studies on parasites and antiparasitic agents. The fields of parasite biology and biochemistry accumulated a large volume of information that led to the possibility of rational design of antiparasitic agents. There is renewed hope for discovery of more selective and less toxic drugs against parasites.

At the present time infections by parasites, both protozoal and helminthic, constitute the most prevalent diseases in the world. The World Health Organization estimates that there are at least 3 billion people in the world who are infected with parasites. Many of these harbor more than one infection. The prevalence of these infections, especially in developing countries, is not only a cause of untold human suffering and mortality but a growing impediment to better local and global economies.

The prime aim of this book is to discuss critical metabolic reactions and cellular structural features that are essential for survival of parasites, particularly those that differ from those of the host. A comprehensive discussion of selective targets in parasites for old and new drugs is long overdue.