Animal host-microbe interactions
The ecology of infectious diseases, as we currently recognise it, has been a major field of scientific research for over a century. Since the early work of John Snow, describing the epidemiology of cholera in 1850s London, and Ronald Ross, describing the transmission dynamics of malaria at the end of the 19th century, through the mathematical models of Kermack & McKendrick in the 1920s, and Anderson & May's revolutionary modelling of infectious disease dynamics in the late 1970s, the field of disease ecology has always sought to combine cutting‐edge analytical and theoretical tools with observational and experimental data to understand the key drivers of infectious diseases. Through this body of work we now have a comprehensive understanding of many of the ecological factors underlying the transmission, spread and impact of infectious diseases, whether they be in wildlife, livestock or humans. In particular, we now recognise fundamental, unifying features of all infectious disease systems, such as the importance of the relationship between host density and transmission, the parasite's basic reproduction number (R0) and minimum threshold population sizes ('critical community sizes') below which the parasite cannot persist (Hudson, Rizzolli, Grenfell, Heesterbeek, & Dobson, 2002). We also understand that the heterogeneities between individual hosts that can, through the existence of superspreaders, dramatically alter parasite transmission potential (Paull et al., 2012). And we are increasingly aware of the potential for parasites to alter host behaviour (Adamo & Webster, 2013) and regulate host population sizes (Tompkins & Begon, 1999).