Herpes zoster ophthalmicus Herpes zoster ophthalmicus Herpes zoster ophthalmicus (HZO) and also known as ophthalmic zoster is a disease characterised by reactivation of dormant varicella zoster virus residing within the ophthalmic nerve (the first division of the trigeminal nerve). This condition is an important subtype of shingles, representing 15% of all cases. Herpes zoster ophthalmicus is transmitted via direct contact or droplets. Varicella zoster virus is a DNA virus which produces acidophilic intranuclear inclusion bodies. The virus is neurotrophic in nature. The frontal nerve is more commonly affected than the nasociliary nerve or lacrimal nerve. Anterior uveitis develops in 40–50% of cases with
Foreign animal disease Foreign animal disease A Foreign animal disease (FAD) is an animal disease or pest, whether terrestrial or aquatic, not known to exist in the United States or its territories. When these diseases can significantly affect human health or animal production and when there is significant economic cost for disease control and eradication efforts, they are considered a threat to the United States. Another term gaining preference to be used is Transboundary Animal Disease (TAD), which is defined as "those epidemic diseases which are highly contagious or transmissible and have the potential for very rapid spread, irrespective of national borders, causing