Herpes is an infection that is caused by a herpes simplex virus (HSV), according to Medline Plus, a patient information website jointly maintained by the National Library of Medicine and the National Institutes of Health. Oral herpes causes cold sores, also known as fever blisters, around the mouth or face. Genital herpes affects the genitals, buttocks or anal area. Regardless of where the disease presents, herpes infections follow four characteristic stages.
Prodrome
A prodrome is an initial phase of early or premonitory symptoms that precede the full-blown disease. According to a 2008 report in the "Archives of Internal Medicine," approximately 60 percent of people with oral or genital herpes report prodromal symptoms including tingling, itching, burning, stinging or extreme sensitivity on the parts of the body where lesions subsequently appear. In some cases, symptoms might be accompanied by visible signs such as subtle swelling or redness. Prodromal symptoms typically last between 2 hours and 2 days, and end with the appearance of lesions.
Early Lesions
The defining feature of herpes infections is the herpes lesion. According to the article in "Archives of Internal Medicine," lesions typically begin as bumps or "papules" on a base of red, swollen skin which develop, over the course of a few hours, into blisters filled with clear or cloudy yellow fluid. The blisters are tiny (1 to 2mm), painful and may occur in clusters or as isolated lesions. Sometimes, according to MedlinePlus, several blisters will coalesce into a single, large blister.
According to "Harrison's Principles of Internal Medicine," oral herpes lesions can be found anywhere on or inside the mouth and throat and sometimes on the face. Approximately 90 percent, however, are found on the red border of the lip, known as the vermillion. In women, genital herpes may appear anywhere on the vulva (external genitalia), the urethra or inside the vagina including the uterine cervix, the lining of the uterus and the fallopian tubes. In men, genital herpes may develop on the head or shaft of the penis, the urethra or the prostrate. In both genders, the lesions can appear on the buttocks, anus, rectum, thighs and perineum (space between the genitalia and the rectum).
Late (Healing) Lesions
After about 3 or 4 days, according to the "Archives of Internal Medicine" article, the lesion will rupture and ooze. At this point, the lesion may be painful, itchy or both. Oozing is accompanied by the formation of a yellow, granular crust or scab that will eventually slough to reveal pink, healing skin. Typically, the American Social Health Association (ASHA) says, the process takes about 8 to 10 days for recurrent lesions. Primary lesions take longer---sometimes up to 4 weeks, notes the U.S. Centers for Disease Control and Prevention.
Latency
A distinguishing characteristic of herpes viruses described in "Harrison's Principles of Internal Medicine" is the ability to remain latent or inactive in a person's nerve roots. Reactivations of the virus are usually, but not always, accompanied by symptoms. Symptomatic reactivations may occur as often as six times a year in some people or never at all in others. There is no cure for herpes. Asymptomatic people can still infect others in a process known as "asymptomatic shedding."
References
- MedlinePlus: Herpes Simplex
- "Archives of Internal Medicine;" The Treatment of Herpes Simples: An Evidence-Based Review; C. Cernik, K. Gallina, and R.T. Brodell; June 2008
- Herpes Simplex Viruses (Chapter); L. Corey; In: "Harrison's Principles of Internal Medicine, 17th edition;" A.S. Fauci, E. Braunwald, D.L. Kasper, S.L. Hauser, D.L. Longer, J.L. Jameson, and J. Loscalzo (Eds); 2008
