There are two types of herpes simplex virus (HSV), which are called HSV-1 and HSV-2. Both viruses have distinctly different DNA and both cause oral and genital lesions. However, HSV-1 causes about 80% of all oral lesions, only about 20% of genital lesions, while HSV-2 causes the opposite (about 80% of genitalia and 20% of oral). The study also showed that up to 40% of genital herpes in adolescents is caused by HSV-1 because oral/genital contact is reported to increase (transmitted through oral sex).
Oral herpes (HSV-1) infection (or exposure without obvious infection) is common. About 65% of the population in the United States has antibodies to HSV-1 before the age of 40. This article will focus on HSV-1 or oral herpes, but not HSV-2, commonly referred to as genital herpes. Genital herpes is considered a sexually transmitted disease (STD). In addition, the HSV-2 virus should not be confused with human papillomavirus (HPV) (the cause of genital warts) and some types of cervical cancer and other cancers.
