EFO_0007542 (visna) is a viral infectious disease that results_in infection located_in brain in sheep and goats, has_material_basis_in Visna/Maedi virus , which is transmitted_by droplet spread of oronasal secretion, and transmitted_by ingestion of contaminated water, milk or colostrum. The infection has_symptom hindlimb weakness, has_symptom head tilt, has_symptom ataxia, has_symptom incoordination, has_symptom muscle tremors, has_symptom paresis, and has_symptom paraplegia. Also known as: Ovine encephalomyelitis, Visna.