Herpes labialis, also known as orolabial herpes, commonly known as cold sores on lips or fever blisters, is an infection of the lip or mouth by the herpes simplex virus. It’s a highly infectious, but not very virulent or dangerous (in most cases), disease for which there is no cure. It produces small blisters or sores around or inside the mouth, few in number (often only one), lasting for two weeks or less. The infection may be contagious without showing symptoms at all, as the virus is capable of reproducing itself on the skin without generating a sore or blister. The disease persists in a dormant phase and recurs periodically.

Symptoms Of Herpes Labialis

The primary symptom of the disease is mild inflammation of the mucous membranes of the mouth and of the gums, and the eruption of one or more sores or blisters on the lips, inside the mouth, or on the gums. Other symptoms, which are more likely to occur in the initial outbreak of the disease and not as common in recurrence, include headache, nausea, sore throat, and fever. An outbreak of the disease may occur with
no symptoms at all, particularly in a recurrent phase.

The phases and progression of the disease are:

1. Latent phase, remission, or incubation. In this phase, before the initial outbreak or between outbreaks, the virus retreats to sensory nerve endings and goes dormant, producing no symptoms. Contagion is still possible during this period. Remission periods between outbreaks typically last as much as a year, or sometimes longer, although outbreaks can occur as often as once a month.
2. Prodromal phase. Pre-blister symptoms may, but need not necessarily, occur during this phase, typically an itching or discomfort at the infected site. This is the best time to begin a course of treatment with topical antiviral drugs.
   
3. Inflammation/Pre-Sore phase. In this phase, which covers about three days, the skin first becomes inflamed and then forms fluid-filled blisters or “vesicles” clustered together.
   
4. Open Sore phase. All of the vesicles burst open and release a watery discharge. This is the most infectious part of the cycle, and also the most uncomfortable and painful. It typically lasts about one day before crusting begins.
5. Crusting phase. A crust or scab-like covering forms over the sore, which remains painful. Any breaks in the crust allow virus-filled fluid to leak out; the victim is still highly contagious. This lasts about three days without treatment.
   
6. Healing phase. The virus returns to latency and new skin forms underneath the crust. This lasts about five days. Contagion is possible during any of these phases (or at any time once the virus is contracted), but is much more likely during the open sore and crusting phases.

Treatment Of Herpes Labialis

Treatment of the disease, if undertaken, usually consists of topical substances that can reduce the duration of the outbreak. Aciclovir and penciclovir are two antiviral medications that can reduce the duration of symptoms by roughly ten percent. Famiciclovere or valaciclovere can be taken orally in a single mega-dose; this is also effective. (More so than a standard course of the drug over a week.) Non-antiviral substances, including docosanol (a form of alcohol) and even zinc oxide, can be used topically with similar results.

Prevention Of Herpes Labialis

There is no watertight way to prevent infection with herpes labialis, since the victim can be infectious to some degree at any time. However, the chance of transmission can be reduced by avoiding touching active lesions and washing hands often during an outbreak, and avoiding contact with others, especially by the infected area (e.g. through kissing or oral sex).