Herpes simplex virus exists in two types (HSV-1 and HSV-2); primary infection of HSV-1 generally occurs during childhood and is fequently asymptomatic, however, HSV-2 is one of the fastest-growing sexually transmitted diseases which can also be transmitted during childbirth through cervical secretions. For this reason, it is important that pregnant women receive a blood test for antibodies to HSV. Primary infection is always accompanied by specific IgM antibodies which are produced as early as one week after infection and persist for approximately 6 weeks but may or may not be found during reactivation. Significant elevation in IgG antibodies appears in primary infections as well as recurrent ones, and they persist in reduced levels throughout the entire life of the infected person. With accurate diagnosis, measures can be taken to prevent transmission.