Horn curvature usually differs significantly between males and females. Males exhibit a smooth, even curvature throughout the entire length of the horn. In contrast, horns show their greatest curvature near the tips. This virus is contained in dark brown or black scabby lesions around the eyes, nose, muzzle, ears, or sex organs of goats and sheep. The virus is contained in the scabs which dry and slough off, and is known to remain active in scabs laying on the ground for at least 30 years.
Goats grazing in the area can then pick up the virus through cuts or abrasions.
Manifestation of the virus has periodically occurred in goat populations throughout Southeast Alaska and, while not common, is not considered unusual. Orf does not affect the edibility or quality of goat or sheep meat. However, through contact with the lesions, the disease can be transmitted to humans. The disease manifests itself in humans in the form of small blisters. Although antibiotics have no effect on the virus, symptoms can be treated.