Preface

The burden of disease has implications that extend beyond the impact of disease on individual health and welfare. A typical initial consequence of this burden is an effort to determine how to respond in terms of mitigating and containing the threat. Despite such efforts, however, when disease occurs on a wide scale, with a large health impact on many individuals, its burden can influence the shape and destiny of societies. For example, the plague – a zoonotic disease transmitted from rodents to people – had dramatic effects on the populations of Europe. It killed so many that land went unused, and some historians believe the lack of people led to labour shortages, which created incentives to invest in labour-saving devices and initiated the Industrial Revolution. Similarly, the arrival of Europeans to the Americas brought new diseases, such as smallpox, which decimated populations and reduced wood burning to such an extent that the reduction in carbon dioxide levels affected the climate. In an animal context, the presence of diseases, such as trypanosomiasis caused by tsetse flies, limits which species can be kept and explains why cattle farming is limited in many parts of Africa. The presence of disease may also lead to restrictions on trade and movement of animals that impact society. The most apparent in today’s trading system is the presence or absence of foot and mouth disease. (…)