User:Mr. Ibrahem/Herpesviral encephalitis

Herpesviral encephalitis is inflammation of the brain due to the herpes simplex virus. Symptoms commonly include headache, fever, confusion, and weakness. Less commonly neck stiffness and abnormal speech may occur. Onset is generally over a couple of days. Complications can include seizures, diabetes insipidus, and autoimmune encephalitis.

It most commonly occurs due to herpes simplex virus-1 (HSV-1), with less than 10% of cases due to herpes simplex virus-2 (HSV-2). About a third of cases occur as an initial infection, while two thirds occur as a recurrence; though only 10% have a history of cold sores. Diagnosis is generally based on symptoms, supported by cerebral spinal fluid analysis and MRI.

Treatment is with acyclovir. Anticonvulsants may be used to decrease the risk of seizures. The disease is most severe in the young and the old. About 20% experience significant long term disability. The risk of death is between 1% and 8%.

Herpesviral encephalitis is rare, affects about 1 in 100,000 newborns, 1 in 400,000 children, and 1 in 150,000 adults in the United States. Males and females are affected with similar frequencies. About half of cases develop in those over the age of 50. It is the most common cause of infectious encephalitis in the developed world. The disease was first described in humans in 1935.