Toxoplasma gondii in wildlife traditionnally harvested by Inuit of Nunavik, Canada

• Main Author: Bachand, Nicholas
• Other Authors: Hill, Janet, Ravel, André, Stephen , Craig, Reeder, Bruce
• Format: Thesis
• Language: unknown
• Published: 2019
• Subjects: Toxoplasma gondii; wildlife; exposure assessment; risk perception; Canada; Nunavik; inuit
• Online Access: http://hdl.handle.net/10388/11988

For centuries, Inuit have consumed wildlife. For decades, high levels of Inuit exposure to Toxoplasma gondii have been reported in Nunavik, Canada. This is puzzling given the rare occurrence of felids, the only definitive host for T. gondii, throughout this region. The handling and/or consumption of wildlife, more particularly the consumption of raw tissues, have been identified as risk factors for T. gondii exposure in Inuit. Yet, little is known about wildlife as reservoirs for T. gondii throughout Nunavik, largely due to lack of a sensitive direct detection method needed for a large-scale study. The rationale for this thesis was to determine whether wildlife poses a risk for Inuit exposure to T. gondii in Nunavik. This thesis first set out to confirm whether the magnetic capture and real-time PCR technique can be used to detect DNA of T. gondii in wildlife by assessing the PCR prevalence in tissues of foxes trapped throughout Nunavik. Then, seroprevalence (MAT) and PCR prevalence (MC-PCR) of T. gondii were compared in ringed seals, geese, ptarmigan and caribou to determine whether serological results can predict an animal’s infection status. The probability that Inuit are exposed to T. gondii through consumption of goose tissues was then estimated in a quantitative exposure assessment. Lastly, we determined whether Inuit awareness, knowledge and risk perceptions ofparasites in wildlife influence the adoption of health-protective behaviors that mitigate exposure to foodborne parasites based on multivariable logistic regression analysis. DNA of T. gondii was detected in 44% (95% CI: 28-60%) of foxes from four locations in Nunavik. DNA of T. gondii was also detected in 9% (CI: 3-15%) of geese, but not in other wildlife species including 20% (95% CI: 12-31%) of ringed seals and 26% (95% CI: 14-43%) of caribou seropositive on MAT. In geese, parasite load was quantified as highest in heart, followed by brain, breast muscle, liver, and gizzard. Overall, given the consumption of 4 goose tissues, there was a 32% ...