The Herpes Simplex Virus (HSV) IgM test does culture or molecular detection of the contagious virus to diagnose Herpes infection. The presence of HSV-1 IgM antibody in blood is an indicator of active Herpes Type 1 infection. The virus is a member of the Herpesviridae family. The infection due to HSV is classified into Type 1 and Type 2. In HSV-2, the stomatitis is found in urogenital areas in adults mostly and is a form of sexually transmitted disease. In HSV-1, mild to severe sore or stomatitis is found in areas of mouth and lips. The sores are called fever blisters or cold sores. It is associated with orolabial infection and HSV encephalitis. HSV-1 is also known as oral Herpes.