Methyl parathion comes inside.

Research Public health scientists are increasingly discovering that the recent emergence or re-emergence of infectious diseases has an origin in environmental change (McMichael and Martens 2002; Morse 1995; Patz et al. 2000). These environmental changes encompass social processes such as urbanization and creation of transportation infrastructure, as well as eco-logic processes such as land and water use, biodiversity loss, and climate change. Concern surrounding these trends has inspired much exploratory research because these phenomena are often anthropogenic, interrelated, and accelerating. Yet there remains a pressing need to more clearly define the causal relationships, leading from a distal environmental change to alterations in more proximal environmental characteristics and disease transmission cycles, which eventually lead to a shift in the prevalence , distribution, or severity of an infectious disease (Figure 1). In this article we focus on the intermediary relationships between proximal environmental characteristics and transmission cycles. Environmental sciences have traditionally focused on the links between distal environmental changes and their effects on proximal environmental characteristics, whereas public health scholarship has focused on the link between transmission cycles and disease burden. We argue and provide a framework for leveraging the wealth of prior research in both realms by highlighting the links between them. These links are conveniently defined through a matrix formulation in which system elements from one component are mapped onto system elements from another component. The matrix cells can then be used to provide information on what is known about the particular link. This matrix formulation is consistent with a dynamic systems approach that accounts for feedbacks, a central feature of complex systems. The Environmental Change and Infectious Disease (EnvID) framework uses a systems theory structure to integrate and analyze disparate information from a variety of disciplines. Our ultimate goal is to identify knowledge gaps and define research directions as well as to develop relevant study designs and approaches for data analysis so that knowledge about environmental change can be incorporated appropriately into the study and control of infectious diseases. In the ensuing section, we survey the literature on contemporary frameworks of environmental change and infectious disease. Next, we motivate and describe the EnvID framework. We then use this framework to generate a putative matrix of plausible relationships between proximal environmental characteristics and transmission cycles. This matrix can be used to assess the strengths and weaknesses of existing knowledge and thus prioritize avenues for future research. During the modern era …