Genital herpes is a common sexually transmitted disease (STD) caused by the herpes simplex virus 1 (HSV-1) or herpes simplex virus 2 (HSV-2). The majority of genital herpes is caused by HSV-2 infection. However, recent studies indicate that as many as 50% of genital herpes are now due to HSV-1 infection.
Viral Shedding of Genital Herpes (HSV)
HSV was isolated from the genital mucosa in 38 of the 53 HSV-2–seropositive subjects (72%) who reported no history of genital herpes, and HSV DNA was detected by the polymerase-chain-reaction assay in cultures prepared from genital mucosal swabs in 6 additional subjects. The rate of subclinical shedding of HSV in the subjects with no reported history of genital herpes was similar to that in the subjects with such a history3.
Herpes Simplex Virus 1 (HSV-1)
The World Health Organization (WHO) estimated that 67% of the population (3.7 billion people) worldwide is infected with HSV-1 in 2016. Infection usually occurs during childhood and remains lifelong. HSV-1 mainly infects the mouth and causes oral herpes (also known as cold sores), but it can also infect the genitals.
Herpes Simplex Virus 2 (HSV-2)
In 2016, the WHO reported that approximately 13% (491 million) people aged 15-49 are living with HSV-2, with more women (313 million) being infected than men (178 million). HSV-2 mainly infects the genitals and is a major cause of genital herpes.
(REF: Looker, K. J., Garnett, G. P., & Schmid, G. P. (2008). An estimate of the global prevalence and incidence of herpes simplex virus type 2 infection. Bulletin of the World Health Organization, 86, 805-812A. )
(REF: Xu F, Sternberg MR, Kottiri BJ, et al. Trends in herpes simplex virus type 1 and type 2 seroprevalence in the United States. JAMA, 2006. 296(8): 964–73.)
(REF3: Reactivation of Genital Herpes Simplex Virus Type 2 Infection in Asymptomatic Seropositive Persons)