Anthropogenic land use change and infectious diseases: a review of the evidence

Humans have altered ecosystems worldwide, and it is important to understand how this land use change impacts infectious disease transmission in humans and animals. We conducted a systematic review 305 scientific articles investigating how specific types of anthropogenic land use change influence infectious disease dynamics. We summarized findings, highlighted common themes, and drew attention to neglected areas of research. There was an increase in publications on this topic over the last 30 years spanning diseases of humans, livestock, and wildlife, including a large number of zoonotic pathogens. Most papers (66.9%) were observational, 30.8% were review or concept papers, and few studies (2.3%) were experimental in nature, with most studies focusing on vector-borne and/or multi-host pathogens. Common land use change types related to disease transmission were deforestation/forest fragmentation/habitat fragmentation, agricultural development/irrigation, and urbanization/suburbanization. In response to anthropogenic change, more than half of the studies (56.9%) documented increased pathogen transmission, 10.4% of studies observed decreased pathogen transmission, 30.4% had variable and complex pathogen responses, and 2.4% showed no detectable changes. Commonly reported mechanisms by which land use change altered infectious disease transmission included alteration of the vector, host, and pathogen niche, changes in host and vector community composition, changes in behavior or movement of vectors and/or hosts, altered spatial distribution of hosts and/or vectors, and socioeconomic factors, and environmental contamination. We discussed observed patterns in the literature and make suggestions for future research directions, emphasizing the importance of ecological and evolutionary theory to understand pathogen responses in changing landscapes.