LE3 .A278 2023

2023

Smith, Todd
Ferguson, Laura

Acadia University

Bachelor of Science

Honours

Biology

Biology

Microplastic pollution poses a threat to environments around the world. Mosquito larvae readily ingest microplastics encountered in aquatic environments and potentially retain them in the Malpighian tubules of terrestrial adults. The influence of microplastics on mosquitoes remains unclear and requires further research. The objectives of this study were to determine whether microplastic contamination alters aspects of vector physiology that contribute to vector competence, and to investigate if this contamination affects the response of Culex territans to the protozoan blood parasites of the genus Hepatozoon. Wild-caught Culex territans were reared in increasing concentrations of polystyrene microplastics, including control (0 beads/mL), low (20 beads/mL), high (200 beads/mL), and ultra (2000 beads/mL) conditions. Measurements of vector physiology included mortality of larvae, pupae, and adults, developmental rate of larvae, body size of adults, and post-infection survival in the presence of Hepatozoon parasites. Exposure to different levels of microplastics did not significantly affect aspects of vector physiology; however, the time of year when larvae were collected influenced aspects of vector physiology. To investigate potential interactions of microplastics and parasites, the intensity of H. clamatae in infected mosquitoes under different treatments was quantified using qPCR. Parasite intensity was not significantly influenced by microplastic exposure; however, mosquitoes in the control treatment showed higher levels of parasite DNA compared to those exposed to microplastics. Additionally, parasite intensity may correlate with the size of a blood meal ingested by the female mosquito. These findings suggest that microplastic exposure does not affect aspects of vector physiology, but may influence parasite success within the host.

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https://scholar.acadiau.ca/islandora/object/theses:4022