Cold sores

Cold sores: description

When talking about “herpes”, it usually refers to the clinical pictures triggered by herpes simplex viruses. The pathogens, which are further subdivided into type 1 (HSV1) and type 2 (HSV2), cause mainly genital and cold sores. Type 1 is mainly responsible for the “herpes lip”, type 2 is found in genital herpes. If viruses are transmitted from the genital area to the lips, for example in sexual practices, it can also be the other way round.

How come to cold sores? – The transmission path

The transmission of cold sores usually occurs by smear infection, ie by a direct transfer of viruses from one person to another. The viruses are in cold sores on the one hand directly to the infected site, especially in the bladder fluid, on the other hand, they are also distributed in saliva. Infected saliva is thus the main source of infection in this form of herpes. Kissing has a high risk of transmission if there is an active virus secretion.

Over a short distance, the viruses can also be transmitted via the air, ie by droplet infection when sneezing or speaking. Especially in children, the transmission of herpes labialis is particularly common because they often hold their fingers to the mouth and close body contact. The viruses then pass quickly from the hand of one child to the mouth of another.

An indirect infection with cold sores on infected items such as glasses, napkins and cutlery is also possible because the herpes virus can survive up to two days outside the body.

During the initial infection, the viruses enter the body via minute skin and mucosal tears, where they first multiply in epithelial cells on the skin surface, which leads to the typical symptoms. Even after these symptoms heal the herpes viruses remain a lifetime in the body.

Because some of the pathogens migrate along nerve fibers to so-called nerve ganglia – accumulations of nerve cell bodies. There they escape the immune system’s access and remain in a state of rest from which they can awaken under certain circumstances. The process of migrating viruses along the nerve fibers is called retrograde axonal transport. In the case of cold sores, the viruses usually reach the fibers of the trigeminal nerve in its ganglia. This nerve, often referred to simply as the trigeminal nerve, is largely a sensory nerve responsible for facial skin sensation.

Why does cold sore break out again? – The risks of reactivation

The herpes viruses can wake up anytime from their dormant state and cause a new outbreak of cold sores. One speaks then of a reactivation. This usually happens when the immune system is weakened. The frequency of reactivations is individually very different.

Such a weakening of the immune system can have a variety of causes, often a cold or flu-like infections behind it. Cold sores therefore occur especially often in fever. Cold sores are therefore also called cold sores.

Emotional or physical stress can also trigger a reactivation. Thus, cold sores occur increasingly after heavy physical effort, but also in times of greater mental stress. Other risk factors include external damage to the lip, for example in the form of injury or skin damage from increased UV radiation. Also reactivations after the visit to the dentist are possible because the lips are strained during the treatment.

Certain medications, as well as diseases associated with a general immune deficiency – such as AIDS – can cause frequent reactivation. Even hormonal changes, such as during menstruation or pregnancy, can cause cold sores break out.

Herpes: lip as a weak spot?

The reasons why herpes prefers lips are, on the one hand, the high density of sensory nerve fibers, along which the viruses can move. On the other hand, the skin is particularly sensitive at the transition between lip and facial skin. Even herpes on the corner of the mouth is relatively common, because this point is mechanically particularly stressed and can easily tear especially in dry cold and low temperatures.

How common is cold sore?

The herpes simplex virus type 1 is very widespread in the population. The infection is often within the family and usually already in childhood. According to the Robert Koch Institute, about 85 percent of the adult population in Germany is infected with HSV1.

Cold sores: symptoms

Anyone who has not been affected by it, has certainly seen it before in others, the classic “herpes lip”. Symptoms such as itching, tingling and pain usually appear first before the typical blisters develop.

Early symptoms of cold sores

Herpes on the lip often announces itself before the actual outbreak. The early complaints include:

• Tension and numbness
• Tingling and itching
• Stinging and burning
• Redness of the skin at the affected area

The extent of these early symptoms can be very different, occasionally they are completely absent. Before that it sometimes happens, especially with initial infections, to nonspecific symptoms, the so-called prodromal symptoms.

main symptoms

The herpes viruses multiply in the skin cells and destroy them. This causes tissue damage in the form of small ulcers and blisters, which can burst quickly when touched. The blister fluid contains a high concentration of herpesviruses and is therefore very contagious. If the bubbles burst spontaneously after one to two days, small open wounds develop, which close and crust after a few days.

After about a week, the crusts gradually fall off, leaving new, healthy skin. After about ten days, the cold sore is usually healed.

Complications of cold sores

Herpes on the lip is basically harmless, but it can come to a so-called superinfection. The affected areas are additionally infected with bacteria. Open wounds and a weakened immune system favor a bacterial infection. The symptoms can be amplified and last much longer.

Even with a first infection with herpes simplex, the symptoms may sometimes be more pronounced than in later reactivations. Especially in children, the disease can be like a severe influenza infection with a high fever and a strong malaise.

How to investigate cold sores?

As a rule, in the case of herpes labialis, a gaze diagnosis, which is carried out only on the basis of the symptoms, is completely sufficient. The classic “herpes lip” seems so typical that a further examination is not necessary. A simple herpes reactivation does not require a doctor’s visit, only if complications arise or other diseases with similar symptoms must be excluded, special investigations are helpful.

In addition to the detection of certain antibodies, the smallest virus components can be detected (antigen detection). Also, the genetic material of the viruses can be duplicated by a special method and then detected. Finally, the herpes viruses can also be grown and then determined exactly.

How to treat cold sores?

Ultimately, ways to treat cold sores are limited. The active ingredients can be administered either in tablet form or as a cream for application to the lips. Herpes can not be prevented, but the duration of the illness can be shortened.

Cold sores: disease course and preventive measures

Herpes labialis is often very annoying for those affected, not least for cosmetic reasons. After two weeks at the latest, a cold sore is healed in a course without complications. Those affected should avoid stress of any kind whenever possible and support their immune system in the form of a healthy diet, adequate sleep and regular exercise.

In order to avoid transmission of herpes viruses from the lip to other parts of the body, such as the eyes, the affected area should not be touched if possible. Do not puncture or scratch the bubbles, as the fluid is highly contagious. After unavoidable touches, wash your hands thoroughly immediately afterward to further spread Cold sores to reduce.