Until the 1980s serological tests for antibodies to HSV were rarely useful to diagnosis and not routinely used in clinical practice.[39] The older IgM serologic assay could not differentiate between antibodies generated in response to HSV-1 or HSV-2 infection. However, a glycoprotein G-specific (IgG) HSV test introduced in the 1980s is more than 98% specific at discriminating HSV-1 from HSV-2.[40]
There are two types of herpes simplex viruses (HSV), they are termed HSV-1 and HSV-2. These two viruses have distinctly different DNA, and both cause oral and genital lesions. However, HSV-1 causes about 80% of all oral lesions and only about 20% of genital lesions while HSV-2 causes the reverse (about 80% genital and 20% oral). Studies also suggest that in adolescents, up to 40% of genital herpes is caused by HSV-1 because of reported increased oral/genital contact (transmission by oral sex).
Mouth herpes{also known as oral herpes) primarily affects children of more than 6 months of age or who are aged 1-2 years  and it affects adults also.  When this virus is inside your mouth it is sometimes confused with a canker sore. It results in painful red fluid-filled blisters or lesions on the tongue, lips, inside of the cheeks, and gums often accompanied with an itchy or burning sensation. Muscle pain and fever can also be suffered at a later stage.  If treatment is ignored, a herpes infection inside your mouth can be dangerous.
The broader issue is whether, if you do get infected, herpes will ultimately harm your health. Although I don’t want to trivialize this infection, in your general scheme of health, it probably will not. The major concern is that if you are pregnant and develop a new outbreak of herpes, the virus can be transmitted to the fetus, especially during vaginal delivery. What’s more, people with genital herpes have a much greater risk of acquiring HIV if they are exposed. (It’s theorized that the lesion causes microscopic breaks in the skin, allowing HIV to enter the body.)

^ McNeil DG. Topical Tenofovir, a Microbicide Effective against HIV, Inhibits Herpes Simplex Virus-2 Replication Archived 2017-04-09 at the Wayback Machine. NY Times. Research article: Andrei G; Lisco A; Vanpouille C; et al. (October 2011). "Topical Tenofovir, a Microbicide Effective against HIV, Inhibits Herpes Simplex Virus-2 Replication". Cell Host. 10 (4): 379–89. doi:10.1016/j.chom.2011.08.015. PMC 3201796. PMID 22018238.
"Oral herpes is an infection found in the mouth, or on and around the lips, caused by the Herpes Simplex Virus (HSV)," Michael explains. "There are two types or strains of this virus called HSV1 and HSV2. Usually, the HSV1 strain infects the mouth and lips, and the HSV2 strain infects the genitals. It is however possible for HSV2 to infect your mouth and lips."
×