Vector-borne disease, deep-time ecology, and one palaeopathology

Rather than ‘novel’ zoonoses, some of our most serious threats are ‘old foes’ in particular ecological and social settings. The recent outbreak of disease in the Democratic Republic of Congo is precisely an example of this – the ‘old foes’ of malnutrition and malaria reappearing in new ways. It is important to understand how infectious diseases appear and disappear over time. This is not just the phylogeny of an infection; it is understanding how pathogens flourish as a result of human niche-construction and are mitigated by human biological and cultural adaptation. In the context of anthropogenic change and the threat of zoonoses, research into long- and short-term processes of niche construction, adaptation, and multi-species ecologies, encapsulated within One Health approaches such as One Palaeopathology, offers important insights and lessons. In this paper we revisit the complexity of vector-borne disease using malaria. Malaria and other vector-borne diseases are not ‘natural facts.’. Outside of its first appearance in humans, malaria is introduced into regions with the right climate and mosquito species through the movement of people and animals and subsequent environmental modification. It is not a given but a consequence of the long-term relationships between pathogens, vectors, people, and animals. Furthermore, human populations adapt to malaria both biologically and culturally. Using the example of Bahrain, this paper demonstrates how recent historical and deep-time ecological and climatic data can be used to develop a model of local malaria ecology which we then use to test a hypothesis of epidemic malaria occurring on the island during the Justinianic period.