Herpes Simplex Encephalitis

Herpes simplex is the most common form of the herpes virus, and often manifests as cold sores and blisters around the mouth, nose, eyes or genital areas. While herpes cannot be cured, new drugs can help prevent outbreaks of the sores and blisters.

Although some cases of herpes can cause complications such as meningitis, blindness and hearing problems, in most cases the outbreaks are mild and short-lasting.

What causes Herpes Simplex Encephalitis

In rare cases, the herpes virus can enter the brain and cause encephalitis. This normally only happens in people whose immune systems are already compromised, by illnesses such as AIDS, Hodgkin's disease or diabetes, or by undergoing chemotherapy.

Herpes encephalitis is frequently fatal, particularly if treatment is delayed. Unfortunately, since many of the early symptoms mimic the flu (headache, dizziness, vomiting), it is easy to misdiagnose the condition until it is too late.

People who do undergo a severe case of herpes encephalitis and survive often sustain considerable damage in the brain areas known as the "limbic system", including the medial temporal lobe and those areas in the frontal lobe responsible for goal-directed activity and appropriate social behavior.

Survivors of herpes encephalitis thus may display dense anterograde amnesia, some retrograde amnesia, and severe disruptions in social behavior.

by Catherine E. Myers. Copyright © 2006 Memory Loss and the Brain