Herpes zoster: causes, symptoms, and treatment
Herpes zoster is a viral infection that should not be confused with herpes simplex and is caused by the same virus as chickenpox.
In this article we will explain what this condition consists of, what its causes are and what we can do to treat it.
What is shingles?
Herpes zoster (HZ) is a local reactivation of the chickenpox virus that remains latent, so you need to have had chickenpox to suffer from this disease. This occurs after the primary infection has occurred and the virus is present in the spinal cord’s spinal nodes or cranial nodes.
Statistics indicate that between 15%-20% of those affected by chickenpox will develop shingles at some point in their lives. The virus returns in different situations intermittently, but usually with a weakening of the immune system.
When a person is infected with the Varicella-Zoster virus (usually in childhood but also in adulthood), he or she develops chickenpox, a disease characterized by reddish watery rashes on the skin, which then turn into scabs. Fever is also a symptom of this disease. After about two weeks our body takes control of the infection and the symptoms are reduced .
However, even if the symptoms are not present, it does not mean that the virus has disappeared, as it can remain inside the body and manifest itself throughout life. Although in the early stages of chickenpox, the virus invades the nerve endings of the skin, it can migrate to some chains of nodes along the spinal cord and brain, where it remains hidden even for decades.
Below you can see a video in which an expert talks about these diseases.
Signs and Symptoms
Shingles is not only a visually very unpleasant disease, but can cause great pain to the person who suffers it . The symptom picture usually starts with the patient’s discomfort: the patient is tired and fatigued. After two or three days, pain and itching appear and in many cases a great deal of sensitivity in the area of the affected nerve and then the skin manifestations occur, with reddish swelling in this area and cluster-like nodules forming. Later, vesicles are formed which can be of different sizes, even reaching the size of a pea. As the days go by, the skin dries up and scabs appear.
Normally, the skin manifestation takes place on the skin of the chest or abdomen, which commonly starts at the spine and extends to the front of the body, as a half-belt (which is why this infection is colloquially called shingles). It can sometimes lead to paralysis of the trunk, although this is rare.
However, when the virus is found in the cranial nerve, shingles can also appear on the face, for example in the eye, nose, forehead, jaw and scalp of one half of the face (called shingles ophthalmicus). This can cause serious problems, because if it affects the cornea of the eye it can even lead to vision loss.
When herpes occurs in the ear, it is called zoster oticus and in up to 60% of cases it causes facial paresis , that is, paralysis in the face (usually disappears over time). Shingles can occur anywhere in the body (including the genitals), and occurs at any stage of life when there are conditions in which the immune system is not functioning properly. It most often appears after age 50.
Postherpetic neuralgia: when herpes becomes complicated
The symptoms of herpes zoster usually last 2 to 4 weeks, although sometimes the outbreak is complicated and what is known as postherpetic neuralgia appears, as the pain continues but not the skin manifestations.
Just under 4% of patients with herpes zoster experience this complication, which may persist for months or years or permanently. The pain of postherpetic neuralgia can be sharp and intermittent or constant and can be very debilitating.
Without doubt, the best treatment for herpes zoster is prevention, and to this end vaccination has proven to be very effective in more than 50% of cases. However, in Spain the social security does not cover its administration and in Europe it is only authorised for those over 50 years of age. The possibility of vaccination for chickenpox exists, but some studies conclude that although it reduces the symptoms and appearance of chickenpox, herpes zoster continues to appear.
When a person suffers from this problem and it manifests itself, treatment should start as soon as possible , but not to eliminate the virus, which is not possible, but to alleviate the symptoms. Doctors usually prescribe creams such as acyclovir or corticoids to relieve pain and also antiviral drugs. In cases where postherpetic neuralgia occurs, different drugs may be given, including gabapentin, cyclic antidepressants, or lidocaine patches. Opioid analgesics may be necessary and intrathecal methylprednisolone may be beneficial. Recent studies suggest that injecting several times botulinum toxin A into the area may reduce pain.
Differences between herpes zoster and herpes simplex
It is important not to confuse herpes zoster with herpes simplex (labial and genital) , as they are produced by different viruses, which belong to the viral family herpesviridae. Herpes zoster is caused by the varicella-zoster virus (VZV) as mentioned above, also called human herpes-3 (HHV-3). However, herpes simplex is spread by the herpes simplex virus (HSV-2) in the genitals) and (HSV-1) in the area of the lips, cheeks, or nose.
How it is spread
In the case of herpes simplex, it is not necessary to have had chickenpox, so it is spread from person to person, for example, with a kiss. Herpes zoster is not contagious from one person to another; however, the individual with herpes zoster can transmit the virus from one person to another when the subject who is exposed to the virus has not previously had chickenpox. When this occurs, the person does not develop shingles, but rather chickenpox.
If you want to know more about shingles, you can view the audiovisual content below.