Malaria remains one of the preeminent global health problems. The challenge presented by malaria does not stem simply from the magnitude of the problem; indeed, there are other diseases causing as much or more morbidity and mortality. Because of its great biological and social complexity, achieving control of malaria has an almost totemic value beyond its simple contribution to ill health, enormous as that is. Malaria is probably one of the most “modeled” of infectious diseases, a tradition beginning with Ronald Ross and developing through classical approaches by Macdonald, Dietz, Molineaux, and many others. Most classical attempts at modeling were driven by the underlying belief that malaria could be eradicated, and the focus was on understanding the relationship between vector and host with the aim of defining conditions under which transmission could be interrupted. It is a striking feature of practically all attempts to model malaria and until quite recently there was no explicit attempt to incorporate morbidity. It would be possible to read the vast majority of modeling literature without ever realizing that malaria killed anyone!
This special edition of the journal comprises a series of papers stemming from what is perhaps the most ambitious attempt ever made to apply mathematical models to understanding malaria. The impetus to this undertaking was the need to understand the possible effects of interventions, particularly vaccines, which do not, at least initially, set out to eradicate malaria but to bring it under control. The authors present modeling approaches to a complete range of issues, from understanding infectiousness, immunity, morbidity, and mortality to predicting the short and long range effects of interventions and approaches to estimating cost effectiveness. The ambition is breathtaking and doubtless some would say foolhardy. Having been involved in a minor advisory capacity at the initiation of the project, I know that this was certainly a view held by some. Has the effort been worth while? I don’t know whether the funders of the venture think so but from the point of view of anyone interested in understanding malaria the answer has to be “definitely!” I have no doubt that professional modelers will have a complete range of views on the approaches used and the conclusions drawn, and there will be considerable debate; indeed, the stimulatory effect on the field is one of the main benefits likely to stem from this work. For non-modelers who have an interest in malaria from practically any discipline you can think of, the papers in this series provide a wonderful resource to stimulate thinking and should lead to new insights and provoke new studies in both the field and lab. Are there any dangers in this approach? For the literal minded or uncritical, the authors have taken care to repeatedly point to the assumptions they make, the limitations of both approaches they take, and the conclusions they draw. Whether this kind of approach can lead to useful predictions that guide policy will only become clear with time, but I would recommend that anybody with the slightest interest in the biology or the epidemiology of malaria read and reread every paper in this series.