Elaeophora Schneideri - Clinical Symptoms

Clinical Symptoms

Symptoms of Elaeophora schneideri infestation vary among the different mammalian hosts.

In the normal definitive hosts, mule deer and black-tailed deer, infestations are asymptomatic.

In the white-tailed deer, infestation is also often asymptomatic. However, blockage and thickening of coronary, cephalic, brachial and femoral arteries and sublingual food impaction have been reported in this host.

In both moose and elk, infestation can lead to fatality. Blockage of the carotid and other arteries of the head and face region by E. schneideri adults restricts local bloodflow, leading to ischemic damage to the brain, optic nerve, ears, muzzle and other facial areas. The results are often blindness; walking in circles or poor coordination (ataxia); dermatitis or gangrene of the ears, muzzle or nostrils; abnormal antler growth; or death.

In the domestic sheep, Barbary sheep, Bighorn sheep, goats, and Sika deer, symptoms are typically dermatological, resulting from inflammatory responses to the microfilariae which accumulate under the skin of the face and ears. The resulting lesions have been described by various authors as "dermal encrustations", "tumorous masses", "raw, bloody dermatitis", or "crusty, scabby lesions" of the head and face. Alopecia, blepharitis, and secondary conjunctivitis have also been observed in sheep. Arterial occulsion may also occur in sheep, but to a lesser degree than in moose and elk.