Over the past few years, no doubt as a consequence of HIV/AIDS newspapers have been full of stories about the threat from plagues some such as TB and bubonic plague appear like spectres from the past while apparently new diseases such as E-coli and the Ebola virus threaten to run riot in the future. It is against such a background that Christopher Wills has published Plagues. Their origin, history and future. The title is self-explanatory and in turn Wills examines, largely by means of case studies of bubonic plague, cholera, typhoid, malaria, syphilis and AIDS, the history of each disease, how the aetiology of that disease became to be understood and then how the disease could be controlled. Wills also has a grander scheme in this book I would like to explore with you just how and why such disturbances of the ecological balance give rise to plagues. Wills therefore has dualistic aims: small-scale ones which seek to explain the impact of each individual disease, and the large-scale one of providing an all encompassing theory of plagues that is hinted at in the introduction. It is appropriate therefore to examine how successful Wills is in each of these aims, but before this it is appropriate to make some comments on the style and structure of the book.
Plagues may be broadly classified under the heading popular science, although it by no means provides a systematical analysis of epidemics. Indeed, along with the history and science there are sections that are part biography, part travel writing. Thus, we are introduced to the authors grandmother and father who had respective encounters with typhoid and a black bear whilst living in India during the 1920s. All this is highly entertaining, but for those whose main interest is history it is whether this book is able to shed light on phenomenon such as the fourteenth-century Black Death or Asian Cholera that it has to be judged. The book is divided into five parts.
Part one deals with the nature of plagues and disease. It also discusses what may be termed the mortality transition and overall it seeks to answer the question of why plagues occur. Parts two to four provide the six individual case studies of specific diseases and part five concludes by addressing the relationship between plagues, population and the biosphere.
The sections dealing with individual diseases may be of greatest interest to historians. Chapters 4 and 5 discuss the disease whose name describes the phenomenon - bubonic plague, Yersinia Pestis. Much of Wills discussion focuses on The Black Death, the epidemic that swept through Western Europe during the 1340s and the Great Plague of London, 1665. Both these events mark the beginning and end of the age of plague, in Britain at least, and in many ways are rather exceptional. Also, the association between the Great Plague, the fire of the following year and the subsequent disappearance of plague is noted even though by 1665 plague was far more devastating in the suburbs, precisely those areas which were left untouched by the fire. There is little however, on what caused the disappearance of plague after 1665 or about the social consequences of plague epidemics. In spite of this, Wills strengths lie in his descriptions of how the plague bacillus was discovered and became to be understood during the late nineteenth and early twentieth centuries. Overall then, the chapter provides an interesting account of nineteenth-century biological science coupled with some historical background. The following chapter poses an interesting question; namely, was the recent outbreak of plague in India really plague? Although the evidence is difficult to interpret, Wills concludes that The outbreaks in Beed and Surat may not have been plague after all. While this chapter provides a useful summary of the available evidence, interspersed with accounts of his visit to India and the appalling levels of poverty that can be found in parts of that country, it is difficult to see how such a comparison adds much to his general thesis about the nature of plagues. It does tell us much about popular perceptions of plagues, but that is another matter. Similar problems arise in some of the other sections. Chapter 6 compares the impact of cholera in nineteenth-century English cities with recent outbreaks in Peru. Wills describes the classic piece of epidemiological detective work by John Snow who discovered that cholera could be linked to an infected water supply in the famous Broad Street Pump. Curiously though, one of the most important pieces in the jigsaw that enabled Snow to link cholera to the pump, the widow who each day had a bottle of water fetched from the pump to her house in Hampstead and consequently became the only person in that area to die during this outbreak, is missing from the story. The discussion of choleras epidemiology is once again interesting, but it is sometimes difficult to see the parallels between nineteenth century London and modern-day Peru where poverty, poor sanitation and inadequate medical facilities combine to ensure that cholera still remains a threat.
In the introduction we are led to believe that some an important global theory about how plagues can be understood is to be presented, but as the book enfolds this promise is not quite fulfilled. It is never fully explained precisely how plagues arise out of an ecological imbalance and the final section discusses the relationship between plagues and less virulent diseases. Part of the reason why no important model emerges is that while on page & we are told that plagues are defined as great epidemic or pandemic disasters as the discussion proceeds and the numbers of examples multiply it becomes apparent that many of these cannot really be considered as plagues. Thus, outbreaks of the little known Four Corners virus in North America is compared with bubonic plague and malaria, yet the impact of each disease on the various societies is very different. Likewise, it is difficult to consider that AIDS is really a plague: the threat posed by this virus is indeed frightening; yet mortality rates have increased only slowly, spread over a considerable number of years and recent estimates suggest that overall mortality rates will remain at these low levels. This mortality profile is in sharp contrast to that of the other classic plagues - up to a third of a population could be wiped out from bubonic plague within a few months. Moreover, modern medical advances have meant that the threat from plagues recedes year by year, even in poor countries. Perhaps a better, although far less glamorous title for this book would have been "Infectious Diseases".
Plagues is highly readable, but is of probably only limited interest for most historians, although those working on the history of science in the nineteenth and twentieth centuries should look at the appropriate sections.