Grand Teton National Park Report
The lungworm of elk, Dictyocaulus hadweni (syn: D. viviparus) has been noted in elk since the early 1900's. It is interesting to note that a high percentage of the elk in Teton National Park are positive for lungworm in the spring. Fewer elk are infected as the summer and fall vegetation is usually sufficiently good to allow the elk an abundance of food and a resultant physiological condition that is excellent. Perhaps elk serum proteins are somewhat low in the April-May period when the physiological "low" is reached by the elk . The lack of immunoglobulins may, in part, explain the high prevalence of lungworm infections in elk of the Tetons during early spring months.
Bergstrom, Robert C.
"Parasites of Ungulates in the Jackson Hole Area: Scarabaeoid Beetles Acting on Lungworm, Dictyocaulus hadweni, Larvae in Elk Feces 1979,"
University of Wyoming National Park Service Research Center Annual Report: Vol. 3
, Article 5.
Available at: https://repository.uwyo.edu/uwnpsrc_reports/vol3/iss1/5