The term "the herpes" generally refers to a sexually-transmitted, double-stranded DNA virus, called herpes simplex virus (HSV) type 2 (also known as human herpesvirus 2, or HHV2). This virus is closely related to herpes simplex virus type 1 (HSV-1 or HHV1) , which is the cause of common nonsexually-transmitted cold sores. These two viruses are among the eight members of the herpes virus family to infect humans, causing a variety of illnesses ranging from cold sores to brain infection (encephalitis) to chicke npox to various cancers.

HSV-1 and HSV-2 are members of the Alphaherpesvirus subfamily. HSV-1 (usually the cause of oral herpes which many people call "cold sores") can also be spread to the genitals via oral sex. HSV-2 (usually the cause of genital herpes) can also be spread to the oral region, although this is somewhat less common. For most people who carry the HSV-1 and/or HSV-2 virus, symptoms are mild, infrequent, or altogether un-noticeable. However, people who carry the virus may still shed the virus from their skin when no symptoms are present, and unknowingly transmit the virus to their partners. This is called "asymptomatic shedding." In one study, approximately 70% of new cases of genital herpes were the result of intimate contact with a partner who had no signs or symptoms at the time.

According to the American Social Health Association (ASHA): - About 50 to 80 percent of American adults have oral herpes, which is commonly called cold sores or fever blisters. - About one in five adults in the United States has genital herpes. However, most people (up to 90%) don’t know they are infected because their symptoms are too mild to notice or mistaken for another condition.
Orofacial infection

Herpesviral vesicular dermatitis Classification & external resources Infectious fluid-filled blister on lower lip (herpes labialis) ICD-10 B00.1

1. Prodromal symptoms
2. Skin appears irritated
3. Sore or cluster of fluid-filled blisters appear
4. Lesion begins to heal, usually without scarring
It is estimated that 50% of adults in the United Kingdom are carriers of the Herpes Simplex Virus, many of whom will never exhibit any symptoms of infection. Similarly, 50% of Americans have HSV-1 antibodies in their blood by the time they have become young adults, and by age 50 or over, 80-90% of Americans have HSV-1 antibodies .[2] In the absence of a coldsore one may also transmit the virus through the skin. Oral herpes lesions typically occur on the lips, on the fixed mucosa inside the mouth, including the hard palate (roof of the mouth), and gingiva (gums), but can occur almost anywhere on the face. Oral herpes and cold sores can sometimes be confused with canker sores.

Genital infection Anogenital herpesviral infection Classification & external resources ICD-10 A60. MeSH D006558

1. Prodromal symptoms
2. Itching in affected area
3. Sore appears
4. Lesion begins to heal, usually without scarring.
In males, the lesions may occur on the shaft of the penis, in the genital region, on the inner thigh, buttocks, or anus. In females, lesions may occur on or near the pubis, labia, clitoris, vulva, buttocks, or anus. Symptoms can be confused with that of chlamydia or gonorrhea, so careful observation by a doctor is important.
The appearance of herpes lesions and the experience of outbreaks in these areas varies tremendously among individuals. Herpes lesions on or near the genitals may look like cold sores. An outbreak may look like a paper cut, or chafing, or appear to be a yeast infection. Symptoms of a genital outbreak may include aches and pains in the area, discharge from the penis or vagina, and severe discomfort and burning when urinating.