Viral Infections

There are many viral infections of the skin. Various kinds of warts (e.g. verruca vulgaris and (molluscum contagiosum) are pure skin infections, for example, while chicken pox, rubella (German measles) and hepatitis B and C are general viral infections which also involve the skin. Herpes zoster and herpes simplex, which particularly tends to occur again and again, are relatively common viral infections of the skin. Viruses are not able to metabolise by themselves. To cause an infection, they have to enter the cells of the human organism. The ports of entry for viruses are the mucous membranes during breathing, the digestive tract and the skin.

Herpes zoster (shingles)

Herpes zoster is caused by the varizella zoster virus. On initial infection, the virus causes chicken pox, which nearly every person suffers as a child. As the immune system weakens in middle or advanced age, the viruses which have stayed in the nerve ganglions after the initial infection can be reactivated. The result is then usually an illness which is localised in the area of the nerves concerned. The viruses spread along the nerves, accompanied by characteristic pain. Small blisters or pustules appear in groups in the areas of skin supplied by the nerves, and the skin appears red and swollen. The pustules rapidly fill up, and then slowly dry out. In many cases, the local lymph nodes also become enlarged and painful to pressure. Patients frequently complain of severe pain even before any symptoms appear. Depending on where it occurs, this pain can also be confused with lumbago (lumbar myalgia), heart attack or migraine. Even when the skin symptoms have disappeared again, the severe pain can still continue, sometimes for several months. The pain (zoster neuralgia) is described as burning and shooting, and can also lead to severe sleep disturbance.

The treatment of herpes zoster should begin as early as possible – within the first 72 hours – as the frequency and intensity of the post-zoster neuralgia, i.e. the long-lasting attacks of pain, can then be significantly reduced. Treatment is done both externally and internally with drugs such as aciclovir, brivudin, famciclovir, valaciclovir and, in cases of aciclovir-resistant strains of the varizella zoster virus, with foscarnet. These drugs inhibit the reproduction of the viruses. Local treatment to dry out the pustules is done e.g. with zinc mixtures or mixtures containing phenol-methanol-urea polycondensate, an artificial tanning substance. The effectiveness of local treatment with antiviral substances is disputed, but can be tried in particular cases. Ointments or solutions containing aciclovir, foscarnet, idoxuridin and tromantadin are in use. Severe pain should be treated at an early stage with pain killers, as pain is quickly “learned” by the body, so through early treatment the risk of long-lasting post-zoster pain attacks can be reduced. If post-zoster neuralgia should nevertheless occur, long-term treatment with analgesics (pain-reducing medication), possibly supported by anti-epileptic drugs (medication to suppress convulsions) or tricyclical antidepressants can be used. Tricyclical antidepressants raise the pain threshold. This therapy should be undertaken in cooperation with a neurologist. Local therapy can also be tried with capsaicin cream, or with neural therapy. Neural therapy is the injection of local anaesthetics into the areas of pain.

Herpes simplex (“cold sores”)

This skin disease is caused by two virus strains, the herpes simplex virus types I and II. The type I herpes simplex virus predominantly occurs in the upper half of the body (extragenital type), the type II herpes simplex virus in the lower half of the body, especially in the area of the genitals (genital type).

Initial infection takes place through small lesions in the mucous membranes and in many cases passes unnoticed, without producing any clinical symptoms. Once in the body, the virus stays throughout life in the nerve ganglions of the spinal cord. The viruses in these ganglions can be reactivated at any time, accompanied by the appearance of the typical skin symptoms.

The appearance of herpes simplex symptoms is usually provoked by immuno-suppressive factors (i.e. factors that weaken the immune system) such as general illnesses, viral influenza, colds, exposure to strong sunlight, or even feelings of disgust.

herpes simplex

Herpes simplex

Clinically, herpes simplex infections are characterised by groups of small blisters or pustules on a reddened skin; the pustules soon fill up with pus, ultimately dry out and are then shed as a scab. Subjective symptoms before the pustules actually appear are tightness of the skin, itching and burning. The most frequent localisation for the type I herpes simplex virus are the lips, chin and cheeks. Basically, however, it can occur on any area of the skin, including the lower half of the body. It is also typically accompanied by swelling of the regional lymph nodes. Initial infection in small children is often very severe in the form of so-called gingivostomatitis herpetica, which is an ulcerous condition covering the whole mucous membranes of the mouth and lips and accompanied by a marked feeling of illness as well as restlessness, fatigue, fever, vomiting, and in rare cases even spasms.

Genital herpes simplex produces blisters or pustules that burst rapidly, so that all that is often found are groups of ulcers the size of a pinhead. It is always accompanied by marked swelling of the lymph nodes, and not infrequently also by a burning sensation during urination. In women, the cervix is also often affected as well. An extremely rare complication that can develop in adults is herpes simplex encephalitis (inflammation of the brain). Infection of new born babies with the herpes simplex virus is dangerous as their immune system is not yet fully developed. In the case of new-born babies, the herpes sepsis can affect the brain and other organs such as the liver and spleen. The mortality rate is high. In rare cases, a herpes simplex infection can also occur on the cornea of the eyes. These corneal infections may leave scarring when they heal and so result in impaired vision.

A further complication is eczema herpeticatum, a massive, widespread occurrence of herpes blisters on the skin of patients who have a tendency to eczema such as atopic dermatitis or are suffering from severe general illnesses. This widespread infection is caused by autoinocculation (self-infection) from a herpes simplex e.g. in the area of the lips, or through heteroinocculation from a contact person with a herpes simplex infection. Eczema herpeticatum is an illness accompanied by severe itching, painful swelling of the lymph nodes, and high fever. These symptoms have to be treated internally, and in many cases patients have to go into hospital.

For the treatment of initial infections, or in severe cases, systematic (internal) virus-inhibiting drugs such as aciclovir, brivudin, famciclovir, foscarnet or valaciclovir are given. In the case of localised, uncomplicated attacks, the local application of virus-inhibiting ointments (6 times a day) during the first four days, i.e. in the phase of active virus multiplication, can shorten the illness. Aciclovir, foscarnet, idoxuridin, penciclovir, tromantadin and vidarabin have proved successful. A similar effect is also ascribed to zinc sulphate. In the case of more than 6 to 8 attacks of herpes simplex a year (herpes simplex recidivans), prophylactic treatment lasting up to 1 year with internal, virus-inhibiting drugs can be performed. Also alternative medical methods such as own-blood injections and acupuncture can sometimes bring success against recurring herpes simplex.