Research

Parasites are ubiquitous, but severe outbreaks of disease erupt sporadically in space and time. We seek to understand the mechanisms that drive variation in natural epidemics the consequences for host populations by taking a trait-based approach to disease ecology. Thus, an overarching goal of our research is to mechanistically link physiology, individual-level traits, and population- or community-level disease dynamics.We combine observations of natural systems, theoretical models, and experiments in the laboratory and field. We primarily focus on disease in aquatic systems, that are relevant for basic research, conservation, and human health, but we get excited about disease dynamics in a variety of systems.

Current research topics in the lab:

  1. Parasite transmission is a critical determinant of epidemiological dynamics in human and wildlife populations. We aim to build mechanistic understanding of transmission in dynamic host populations and communities and consequences for host populations. Specifically, we’re interested in understanding how parasite transmission depends on both the traits and densities of hosts and parasites in naturally variable populations and communities. For example, a current project in the lab aims to build and test transmission models for body size-structured host populations, because size can simultaneously affect host-parasite contact rates and susceptibility to infection.
  2. Host-parasite bioenergetics. Epidemiological dynamics depend on the traits of hosts and parasites, but hosts and parasites are heterogeneous entities that exist in dynamic environments. Resource availability is a particularly dynamic and potent environmental driver of within-host infection dynamics (temporal patterns of growth, reproduction, and parasite production). We are currently developing, parameterizing and validating models for resource-explicit infection dynamics by incorporating parasitism into Dynamic Energy Budget theory. We test our models against individual- and population-level experiments with Schistosoma mansoni and its intermediate host snail along environmental gradients. Ultimately, bioenergetic theory for infection could yield a unified, mechanistic framework to predict the consequences of many ecological factors (e.g., resources, temperature, pollution, host density, population size structure, etc.) on disease spread through their effects on physiological traits of hosts and parasites.
  3. Infectious disease in communities. Host-parasite interactions do not occur in isolation. Instead, they are embedded in ecological communities. Other species can alter disease outbreaks by serving as predators, competitors, or prey for hosts and parasites. We are interested in understanding the mechanisms by which these additional species affect host-parasite interactions and identifying the traits that predict which species will have the greatest positive or negative effects on disease dynamics.
  4. Collaborative research: Collaboration is an essential element of successful science, and I believe it is important train advisees to work well with others. I collaborate with several amphibian disease ecologists on a project that aims to assess the potential of boosting amphibian immunity to the virulent pathogen Bd through exposure to the dead parasite (essentially an inactivated vaccination). My role involves building and testing eco-epidemiological models that predict the population-level consequences of disease and “vaccination” by scaling up the individual-level protective effects we’ve previously documented.