The First Report of Elaphostrongylus cervi Infection in Two Imported Wapitis (Cervus canadensis) in Slovenia

This study describes two female wapitis (Cervus canadensis) with neurological signs associated with an Elaphostrongylus cervi (E. cervi) infection. The original host of the nematode parasite is the Eurasian red deer (Cervus elaphus), although other cervids and small ruminants may also be affected. The two wapitis imported from Canada were kept in an enclosure with the Slovenian red deer herd. After developing debilitating neurological signs, the wapitis were euthanized and examined for possible causes. A histopathological examination of the brain of the first wapiti revealed severe diffuse perivascular meningoencephalitis with chronic vasculitis, and some cross-sections of nematodes were found in the leptomeninges. A necropsy of the second wapiti revealed severe pachymeningitis and leptomeningitis, where several adult nematode parasites were found. E. cervi was confirmed by molecular methods. The prevalence of E. cervi in the European red deer population is high, but no study has been conducted to assess its prevalence in Slovenia. This was the first confirmation of E. cervi in Slovenia and the first infection with this parasite described in Europe in a wapiti. Elaphostrongylus cervi should also be considered as a differential diagnosis in Europe for all ruminants grazing on pastures frequented by red deer and showing neurological clinical signs.