Johannah Farner

On our rapidly changing planet, understanding how temperature drives disease occurrence in nature is a necessity if we are to protect the health of humans, plants, and wildlife alike. I combined lab experiments with large-scale field surveys to show that warmer temperatures reduce parasitic pressure on mosquitoes in the western US.

Many diseases are temperature-sensitive, particularly those that involve cold-blooded ectotherm hosts like insects. My research uncovers the role temperature plays in shaping disease burdens in complex natural environments. I use controlled laboratory experiments to isolate the direct effects of temperature on disease risk, and large scale field surveys of infection occurrence across climate gradients to test the real-world relevance of lab-measured temperature impacts. For a mosquito species that is common across western North America and can be killed by ciliate parasite infections, I have shown that infections are more likely at cooler temperatures that suppress the mosquito immune response. Thus, ongoing climate warming may alleviate disease pressure on mosquitoes across large swaths of the west coast.