About 60% of adults and adolescents have suffered primary oral herpes infection, and to 40% of those have recurrent infections.
Recurrent Herpes labialis (oral herpes) affects a large number of adults and adolescents and is often reactivated by:
- stress,
- ultraviolet light (including sunshine),
- fever,
- fatigue,
- hormonal changes (e.g. menstruation)
- and trauma to a site where previous infection occurred.
Oral Herpes Symptoms
Most first-time or primary infections are asymptomatic: cold sores may not appear. Lesions or sores may occur anywhere in the mouth, inside of the cheek or lips. In children primary infection may involve the throat (pharyngitis or tonsillitis).
Primary infection may be accompanied by swollen lymph nodes and fever. In most people, the lesions heal and crust over 10 days, but may persist for longer (2-3 weeks). Regardless of whether or not symptoms are present, viral shedding may occur so that you are infectious to others.
Oral Herpes Latent Infection
To avoid the immune system, the herpes simplex virus (HSV-1) retreats to sensory nerve roots in the trigeminal ganglion, located at the top of the spine, where it remains inactive (latent) for a period of time.
Approximately one-third of people who become infected with HSV develop a life-long predisposition to herpes outbreak infections (recurring infection). Recurrent infection occurs when the reactivated virus travels from the nerve ganglion back to the area where initial infection occurred.
Recurrent Oral Herpes Infection
A number of factors may contribute to reactivation of the herpes simplex virus.
A common sign of reactivation is the cold sore that begins as a reddened area on the border of the lips or nasal passages. Recurrent infection progresses to painful inflamed red spots that swell and fill with fluid forming blisters. The fluid of the blister is full of active infectious virus. Within 2-3 days the blister breaks leaving an ulcerated lesion or sore that usually takes about 10 ten days to crust over and heal.
Recurrent infection may also be asymptomatic so that viral shedding occurs without any signs of being infected. Person-to-person contact can result in spread of the virus to others during asymptomatic AND symptomatic outbreaks.
Recurrent cold sores are usually preceded by warning signs that an outbreak is about to occur. Most herpes sufferers will be aware of a tingling or itching sensation in the day or two before the cold sore erupts.
Cold sores usually appear in the same place as previous outbreaks or close by. Recurrent oral herpes infection may occur as often as monthly in some individuals, while others may have years between outbreaks. Frequency of recurrence is associated with hereditary genetic factors, the health of the immune system and the virulence or strength of the particular strain of HSV-1 involved in infection.
Autoinfection (Autoinoculation)
Herpes infections can be spread from one area to another (autoinoculation). Touching a cold sore can cause herpes of the finger if the virus finds a wound, lesion or other area of damaged skin through which to enter.
Herpes of the finger is known as herpetic whitlow. Autoinoculation is more likely to occur early during primary infection before the body’s immune system contains the primary infection. Infections from autoinoculation are not as likely to recur as infection at the initial site.
Complications of oral herpes infection can occur but are extremely rare:
- atopic eczema,
- encephalitis,
- keratoconjuncctivitis,
- pharyngitis
- and hepatitis.
Treatment of Primary Oral Herpes Infection
Primary and recurrent oral herpes infections generally do not require treatment with anti-viral agents unless underlying illness (e.g. HIV infection) increases the risk of complications from infection.
Prevention of Recurrent Oral Herpes Infection
Measures to prevent triggering factors may reduce the numbers of outbreaks; however, there is currently no effective vaccine to prevent infection, and no treatment that will cure oral herpes infection.
There are some products that may reduce the length of outbreaks.
Read more about herpes infections:
Herpes simplex Virus Infection
Herpes Infection and Reactivation
Infections Caused by Herpes Virus
Oral Herpes Treatment & Prevention
Sources:
Pertel PE and PG Spear. Biology of herpesviruses in Sexually Transmitted Diseases, Third Edition. McGraw-Hill, New York, 1999.
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