HHV-1
Human herpesvirus 1. A herpes virus that causes cold sores and fever blisters in and around the mouth.
Here is a depiction of a typical fever blister caused by HHV-1:</P> NTER><IMG height=154 alt='Fever blister Illustration - HHV-1' src='http://images.medicinenet.com/images/Feverblister.GIF' width=180></CENTER> In rare cases, as when the immune system is severely compromised, this virus can cause infection of the brain (encephalitis).
HHV-1 is also known as herpes simplex type .