herpes simplex virus (HSV)

A type of herpes virus that causes blisters or painful sores on the skin.

There are 2 types of herpes simplex virus. Herpes simplex virus type 1 (HSV-1) causes cold sores and fever blisters in and around the mouth. Herpes simplex virus type 2 (HSV-2) causes genital herpes.

Also called Human herpesvirus 1 (HHV-1) and Human herpesvirus 2 (HHV-2).