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Cold Sores

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Risk factors

You are not alone, herpes simplex labialis (cold sores) is one of the most common skin infections affecting human beings2.

The prevalence of cold sores increases with increasing age of a given population3.

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What is a cold sore?

Herpes simplex labialis (oral herpes), is commonly known as cold sores and is caused by the herpes simplex virus, type 1 (HSV-1)3,4. Herpes simplex virus, type 2 (HSV-2) is mainly responsible for causing genital herpes, however, HSV-2 may spread to the mouth during oral sex which can result in oral herpes4.

Cold sores are a common infection of the mouth area that may affect the lips, mouth, throat or gums4. They are small, painful, fluid-filled blisters and may also be referred to as fever blisters3,4. Cold sores can affect each individual differently but in most cases they are itchy, tingly and unsightly3.

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How do I get a cold sore and are they contagious?

The herpes virus spreads most easily from individuals who have an active outbreak of cold sores4. Cold sores are highly contagious and although during some stages of the cold sore outbreak you are less likely to transmit the herpes virus, the possibility of transmission is almost always present3. You can be infected with the virus if you have intimate or personal contact with an infected individual or if you touch an open cold sore or item that has been in contact with the herpes virus, such as, towels, dishes, infected razors or any other personal item3,4.

Initial infection occurs typically in childhood or adolescence, because during childhood parents may spread the virus to their children in normal daily activities3,4.

A cold sore typically lasts between seven and ten days. However it may last as long as two or three weeks3.

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The five stages of a cold sore outbreak2

1)     Prodromal Stage (1-2 days):

  • This stage is experienced by 46-60% of patients.
    The symptoms in this stage are the first signs of a cold sore and include tingling, itching, inflammation and soreness around the mouth where the cold sore will appear.
  • In patients that have recurrent cold sores, the site of the blister is often the same and is usually located on the upper or lower vermilion border.
  • In some cases the skin in and around the nose or on the cheeks is the target.
  • Some patients may experience a fever during this stage.

2)     Blister Stage (Approximately 2 days):

  • Blisters appear and are filled with clear, yellow fluid.
  • Several separate blisters may appear and form a large crop on the lips that can disfigure the lips.

3)     Weeping Stage (Approximately 1 day):

  • The blisters begin to rupture and expose an open wound that becomes grey in colour.
  • The fluid that drains from the cold sore is yellowish and highly infective and the virus is most contagious at this stage.

4)     Scabbing/Crusting stage (2-3 days):

  • A yellowish scab/crust forms and covers the open wound and the cold sore begins to heal.

The area beneath the scab remains painful and the scab can break and bleed and subsequently form a smaller secondary scab.

5)     Healing Stage (Several days):

  • The secondary scab slowly becomes smaller and begins to reveal pink skin that eventually resembles the surrounding unaffected epidermis.
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Is there a cure for cold sores?

Cold sores eventually do heal but there is no cure for the herpes virus that causes them. Once you are initially infected with the virus it remains in your body forever3. The initial infection may often be asymptomatic and may not be noticed by the patient or by the parents (in the case of an infected child), where other patients may only notice a fever. Alternatively the initial HSV-1 infection could be the most severe and gradually become less intense with recurrence3.

After the initial infection the virus becomes dormant in the nerve tissues of the face2,3. After time the virus may be triggered and the symptomatic cold sores reappear, this is known as recurrence3. Approximately one third of patients who experience the initial HSV-1 lesion experience recurrences3.

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What are the factors that may trigger cold sores?

There are numerous factors that have been identified as possible triggers for recurrence3. The most common triggers are: overexposure to wind, immunosuppression, natural or artificial ultraviolet light (e.g. sunlight or tanning beds), menstrual periods, lip chapping, lip trauma or abrasion, long with:3

Herpes viruses have no cure, however, there are a number of treatments available. Treatments are either prescription (e.g. anti-viral medication) or non-prescription (e.g. topical ointments). These medicines assist in reducing pain and allow the symptoms to diminish sooner3,4.

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