Neurologic diseases in elk and moose, without similar symptoms in white-tailed deer, may indicate infection with what type of organism?

Neurologic diseases in elk and moose that do not present similar symptoms in white-tailed deer are often associated with infections caused by nematodes. Nematodes, also known as roundworms, can have specific life cycles and host interactions that lead to unique disease manifestations in different species. For instance, certain nematodes can affect the central nervous system of susceptible species like elk and moose, leading to neurologic symptoms, while deer may have different susceptibilities or even exhibit asymptomatic infections.

This variation amongst species can be attributed to differences in immune responses, anatomy, and ecology, meaning that the organisms can have distinct impacts depending on the host involved. In contrast, while bacteria, flatworms, and protozoa can cause various diseases, the linkage of neurologic symptoms specifically to elk and moose, without similar effects in white-tailed deer, strongly points to the role of nematodes in this context.