Herpes virus type 4 is also called Epstein-Barr virus. It typically causes infectious mononucleosis, a “kissing” disease. Symptoms include skin rash, fever, sore throat and swollen lymph glands. The virus can be involved in cancers like nasopharyngeal cancer. Herpes virus type 4 is contagious through bodily fluids, including saliva. Kissing, coughing, sneezing, or sharing utensils can make the infection spread.

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.
What's to know about herpetic whitlow? Herpetic whitlow results from infection with the herpes simplex virus. It can occur in adults and children. The main symptom is a painful wound on the index finger or thumb, though it can also develop on the toe. Other symptoms may follow. Here, learn about risk factors, home care, and treatments for herpetic whitlow. Read now
Although it's rare, pregnant women can pass on the herpes infection to their child. This can result in a serious and sometimes deadly infection in the baby. That's why taking steps to prevent an outbreak at time of delivery is recommended starting at 34 weeks into the pregnancy. If you have signs of an active viral infection when it's time to deliver, your doctor will likely recommend a cesarean section for delivery.
HSV infection causes several distinct medical disorders. Common infection of the skin or mucosa may affect the face and mouth (orofacial herpes), genitalia (genital herpes), or hands (herpetic whitlow). More serious disorders occur when the virus infects and damages the eye (herpes keratitis), or invades the central nervous system, damaging the brain (herpes encephalitis). People with immature or suppressed immune systems, such as newborns, transplant recipients, or people with AIDS, are prone to severe complications from HSV infections. HSV infection has also been associated with cognitive deficits of bipolar disorder,[13] and Alzheimer's disease, although this is often dependent on the genetics of the infected person.
Stage 3 -- Recurrence: When people encounter certain stresses (also termed triggers), emotional or physical, the virus may reactivate and cause new sores and symptoms. The following factors may contribute to or trigger recurrence: stress, illness, ultraviolet light (UV rays including sunshine), fever, fatigue, hormonal changes (for example, menstruation), immune depression, and trauma to a site or a nerve region where previous HSV infection occurred.
Primary Infection: This is the first stage wherein the contagion reproduces upon entering from the mucous membrane or skin. Typical symptom is the appearance of oral lesions which may not be present initially resulting in an asymptotic infection. In this case due to lack of symptoms one will be unaware of the presence of an infection. The sores usually takes 21 days to form and become visible, then the blisters will persist up to 10 days before beginning to heal.
A scary finding is that more cases of genital herpes than ever before are now being caused by HSV-1 (the type most people assume only causes mouth sores), and about 85 percent of people with genital herpes don’t even know it. (7) Studies show that about 50 percent of the new genital herpes infections in young adults are due to HSV-1 and about 40 percent in older adults. The fact that most people don’t ever find out they’re infected is one of the reasons that transmission rates are steadily climbing.
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