What is a cold sore?

What is a cold sore?

A cold sore (in medical terms 'herpes labialis' or orolabial herpes) is caused by an infection called the herpes simplexvirus. The type of herpes simplex that causes the cold sore in most cases is the Type 1 (HSV-1). When one gets a cold sore, one experiences a burning, tingling feeling on and around the lips, followed by one or more painful blisters. After a few days these blisters turn into sores, covered by a crust. The skin should heal again within 7 to 10 days, but this is an average and it can take shorter or longer, depending on the person and the intensity of the cold sore.

Complaints and symptoms of a cold sore

A number of complaints and symptoms common to cold sores are :

• A burning or tingling feeling on or around the lips;
• Painful blisters, turning after a few days into sores covered with a crust;
• The skin normally takes about 7 to 10 days to heal;
• A cold sore can sometimes cause apathy and general tiredness;
• During the acute phase (see above symptoms) the cold sore is infectious.

In some cases a cold sore can also lead to genital herpes. It is therefore very important to wash one's hands after contact with the cold sore. For the same reason oral sexual contact should also be avoided.

What causes a cold sore?

A cold sore is normally caused by the herpes simplexvirus (Type 1, HSV-1). In some cases this may be the Type II (HSV-2) virus. Once one has been infected, the patient will retain the virus in their body for the rest of their life. The virus usually nestles in the nerve (nervus trigeminus) which regulates, among other things, the innervation or stimulation of the tongue and facial muscles. The virus may be triggered by exposure to UV-lighting, after which the cold sore appears.

Treatment of a cold sore

The virus is often treated with a salve which claims to prevent the acute symptoms from appearing. The salve contains a UV-filter and zinc salt, to protect the lips against sunlight. The zinc sulphate encapsulates the cells of the herpes virus, so that the healthy cells cannot become infected. The same zinc salve can be used to treat the symptoms of a cold sore. When the symptoms appear, the salve can be applied directly to the cold sore. This will not cure the virus itself, but can prevent a blister forming.