Researchers are still identifying micro-organisms that cause new diseases in humans. A basic factor in the emergence of these diseases is the role played by animals, which act as a reservoir for certain viruses. In favourable conditions, such viruses can cross the species barrier and infect humans. The book takes a close look at two families of virus: orthomyxoviridae and paramyxoviridae, which have infected many species of vertebrates and are responsible for zoonosis. The two main parts of the book describe how the viruses operate, how they spread and the risk factors for humans. In addition to a specific and detailed study of these two micro-organisms, the book highlights the fascinating history of such diseases, their emergence, development and disappearance. They have occurred throughout human history, underscoring the role of the environment and the way it changes, often as a result of human intervention. Sponsored by the Merieux Foundation and written by leading international specialists, this book provides first-class information about these new viruses.

International Workshop organised by the Marcel Merieux Foundation, 21 to 23 June 2000. The debate over the ethical issues raised by stem cell research concerns essentially the practice of taking cells from human embryos and the consequent destruction of the embryo. This work, going to the heart of the controversy over such manipulations, discusses the ethical question of the legal status of the embryo. At the moment when, in France, the bioethics laws have come up for review, questions regarding the statute of the embryo return in the heart of scientific debates. Breakthroughs in the field of embryonic stem cell biology offer a glimpse of the considerable therapeutic possibilities. Research Institutes and Governments, hailed by these new therapeutic perspectives, are attempting to put in place modes of regulation this research that both respond to citizen's aspirations and conform to ethical norms.