Co-infections affect host susceptibility and infectiousness and ultimately alter disease transmission and persistence but how they do so is unclear. We use an immuno-epidemiological approach and a combination of lab and field work to quantify how co-infections interact between each other and the host, how immunity modulates these interactions and how these processes influence the shedding of infective particles in the environment. Our study system is the European rabbit and its common infections: the gastrointestinal helminths T. retortaeformis and G. strigosum, the respiratory bacterium B. bronchiseptica and the virus myxoma (Figure 1).
Host exposure to infections is affected by the survival, development and transmission of infecting agents, which in turn are affected by environmental conditions such as climate and habitat. How do climate changes affect parasite transmission? How do environmental changes affect chronic infections? To address these questions we use a combination of long term studies from more than 30 years of data on a population of European rabbits and its two common gastrointestinal parasites, T. retortaeformis and G. strigosum, in combination with field and lab experiments. Long term climatic data and environmental changes are also available. Our ultimate goal is to understand how long-term climate change and seasonality drive host infection (Figure 2).
Link: NSF-LTREB study
The response of the host to parasite infections can range from either tolerance, by limiting the parasite damage, or resistance, by mounting a response that reduces the parasite burden and eventually develops into some level of long term protection. We are interested in understanding the mechanisms that generate these phenotypes using the rabbit and its two gastrointestinal parasites, T. retortaeformis (Figure 3a) and G. strigosum (Figure 3b), which show distinct life history traits.
Diseases can disrupt the composition and function of the commensal microbiota and host homeostasis. How this happens and how the microbiota influences disease dynamics and severity is still unclear. This study seeks to identify how changes in the intensity of helminth infections impact microbiome assembly and composition in the gastrointestinal tract and vice versa how the microbiome affects parasite establishment and survival. The work is based on laboratory experimental manipulation of the rabbit-T. retortaeformis system and high-throughput DNA sequencing of the host GI bacterial community.