A brief history of zoonoses

Abstract

View Large Image | Download PowerPoint SlideSpillover: Animal Infections and the Next Human Pandemic is the latest work by the award-winning science and nature writer David Quammen, author of (among other things) the popular press books The Reluctant Mr. Darwin [1xThe Reluctant Mr. Darwin: An Intimate Portrait of Charles Darwin and the Making of His Theory of Evolution. Quammen, D. See all References[1], Monster of God [2xMonster of God: The Man-eating Predator in the Jungles of History and the Mind. Quammen, D. See all References[2], The Flight of the Iguana [3xThe Flight of the Iguana: A Sidelong View of Science and Nature. Quammen, D. See all References[3], Wild Thoughts From Wild Places [4xWild Thoughts From Wild Places. Quammen, D. See all References[4], and The Song of the Dodo [5xThe Song of the Dodo: Island Biogeography in an Age of Extinction. Quammen, D. See all References[5]. Most of these tend to focus on megafauna (particularly endangered species) and the increasingly threatened wildernesses in which they live. Thus, at first glance, Spillover appears to be a major departure from Quammen's typical subject matter.However, a perusal of Spillover reveals that these themes are still present, just examined from a different perspective and at a different scale. The megafauna are, more often than not, humans, and the ecosystems are both those through which we move and those that are found within our own bodies. As a result, Spillover is probably the most intimate and personal of Quammen's books to date, and one that likely will resonate with any reader who has ever spent much time suffering at the metaphorical hands of an infectious organism. In Spillover, Quammen describes both why and how diseases are shared between humans and our animal neighbours; he also, as the title suggests, explores whether we can use information on previous and current zoonotic epidemics to predict ones that might occur in the future.Spillover has much to commend it, but two strengths in particular: its treatment of scientific research and the people who conduct it, and its conversational, easily accessible prose. Together, these give the book not only the intensity and excitement of an adventure novel but also a breadth, depth, and accuracy that make it a legitimate educational resource. Where many authors might be content to merely summarise the major points of published papers, Quammen travels the world to interview researchers on the front lines of epidemiology: scientists sampling bats in Australia and Asia, primates in Africa, and monkeys in Bangladesh, for example. As a result, he provides not only detailed background information and accessible definitions to scientific terms (and even equations!) but also vivid first-hand descriptions of work being done in laboratories and in the field.The plethora of case studies examined in Spillover (Hendra, ebola, SARS, Nipah, and HIV, to name a few) act as variations on a theme, driving home the point that nearly all spillover events have certain characteristics in common, even if the associated infectious agents vary in specific traits such as location, host, virulence, and transmissibility. Indeed, Quammen describes disease outbreaks as a perfect storm of factors: ‘Maybe luck…Maybe circumstance. Maybe [population] density. Maybe genetics. Maybe behaviour.’However, he also takes pains to emphasise that, unlike other animal victims of disease, we humans ‘can be pretty smart’; we can, for instance, develop new medications, provide more effective quarantines, and discontinue activities that expose us to pathogens. As a result of this optimistic attitude, Spillover is not bogged down by the many unpleasant (although fascinating) details it contains. Rather than scaremongering, it suggests that epidemiologists can and will learn from previous outbreaks, allowing us to counteract, and even prevent, those that might be on our horizon. Thus, although it might not appeal to germophobes, Spillover is an engrossing, informative, and ultimately rather hopeful book.