Introduction

The epidemiology of infectious diseases is one of the great triumphs of applied ecology. In particular, the public health importance of parasites has lead to a large literature, exploring their impact on the population dynamics, population genetics and evolutionary biology of human populations. An important milestone was the Dahlem Conference on population biology of infectious diseases, held in 1981. The resulting book (Anderson and May 1982) lucidly summarised the contemporary state of parasite ecology and epidemiology. The meeting was also important in bringing together theoretical and empirical workers from a range of relevant disciplines. Their deliberations, in a series of group reports, set the scene for many developments in parasite ecology over the following decade.

Following the advent of HIV/AIDS, there has since been a particular flowering in the quantitative epidemiology of human infections (Anderson and May 1991). By contrast, work on diseases of naturally fluctuating animal and plant populations has had a lower profile. Although there are large bodies of published research on theoretical and empirical aspects of the ecology of infectious diseases in naturally fluctuating host populations, there has been no recent attempt to bring these together systematically. This is partly happenstance but, as we shall see, probably also arises from a lack of empirical knowledge about the details of many interactions. The Isaac Newton Institute programme on epidemic models, held during January–June 1993, provided the ideal venue for addressing this gap between theory and practice. This volume is based on a workshop which we convened during the second week of March 1993.