Social interactions, social networks, and individual behavior are highly likely to influence infectious disease spread in humans and other social organisms, but the extent to which disease transmission is affected by these factors remains poorly known. This project capitalizes on a readily manipulated host-parasite interaction to elucidate these effects and therefore has significant societal benefits. The recent outbreak of Ebola and the continued emergence of new infectious diseases underscore the importance of understanding how disease transmission is affected by behavior and social networks. Established contacts with diverse agencies and non-governmental organizations will allow the investigators to share their results to inform the fields of both human and wildlife health. A series of national and international workshops will allow the investigators to disseminate their novel experimental and modeling methods. A code-free, graphical simulation platform is under development that will allow students at all levels to investigate how individual behavior, movement, interspecific interactions, and resource availability affect disease spread. This platform will be taught to individuals with no computer coding experience through workshops, and simpler versions of this platform will be developed for use in secondary school classes. Postdoctoral researchers, graduate students, and undergraduate students will be trained in rigorous field and modeling research, with clear plans to recruit students from under-served groups. The research leverages a strong international collaboration between US and Australian researchers, and is jointly supported by NSF's International Science and Engineering Office.
The project takes advantage of a well-studied lizard-tick system to examine how spatial and temporal variation in the ecological and social environments interact with individual differences in host behavioral type to influence individual host movements, host social networks and parasite transmission. While these conceptual links are individually simplistic, each link and their interactions present complexities that require new experimental and modeling approaches. Field research will use habitat surveys to quantify the location of lizard resources and refuges and will track all lizards in a study site to document their movements, space-use, social interactions, and their behavioral tendencies. Sampling will also quantify the number of ticks carried by each lizard. These studies will be complemented by a unique experiment that adds genetically distinct ticks to free-ranging lizards. The experiment will quantify individual differences among lizard hosts in parasite resistance, the relative ability of individuals with different behavioral tendencies to serve as conduits for spreading experimentally-released parasites, and the extent to which increased parasite loads alter host behavior, movement patterns and social interactions. Empirical results will be integrated in Bayesian statistical models and individual-based simulation models to test the role of behavioral mechanisms in explaining parasite loads and transmission. The models will then be used to examine how environmental changes such as shifts in land use regimes or climate alterations will influence host-parasite dynamics.
