Shingles (Herpes Zoster): Causes, Symptoms, Transmission, Treatment and Prevention

Shingles is a viral infection that can cause a painful rash. Shingles is caused by the varicella-zoster virus, the same virus that causes chickenpox. Even after the chickenpox infection ends, the virus remains latent (inactive) in the nervous system for years before reactivating as shingles.

Shingles is also often referred to as "herpes zoster." This viral infection is characterized by a red skin rash that can cause pain and burning. Shingles usually appears as a "band" of blisters. This band corresponds to the area where the nerve transmits signals. The rash remains somewhat in a single area. It spreads throughout the body, and most often appears in the chest area, neck, or face.

The likelihood of developing shingles increases with age, which is why it is recommended for all healthy adults over the age of 50. The shingles vaccine is also recommended for adults aged 19 and older who have a weakened immune system due to an illness or treatment.

Transmission mode

Anyone who has had chickenpox in the past can develop shingles. The chickenpox virus remains in the nerve cells near the spine, but it is inactive. Shingles occurs when the virus becomes active again.

The varicella-zoster virus spreads when someone comes into contact with a weeping blister, by touching fluids on contaminated surfaces or directly on the skin. It is not contagious if the blisters are covered or have crusted over.

Symptoms

The incubation period lasts an average of 18 days. The infection often begins with itching, tingling, burning sensations, intense pain, fever, chills, headaches, nausea, and/or diarrhea.

A few days after the onset of skin discomfort (or, rarely, a few weeks later), the characteristic shingles rash will appear. It usually appears as groups of small red spots that eventually turn into blisters. These fluid-filled blisters gradually begin to dry out and scab over. The crust often falls off after a few weeks, and the shingles rash disappears after about two to four weeks. Although less common, in the case of a severe rash, skin discoloration or scarring is possible.

Although shingles can appear almost anywhere on the body, it most commonly affects the torso and face (including the eyes, ears, and mouth). It is often present in the rib cage or waist area.

This characteristic rash is in the form of a stripe or band that affects only one side of the body (right or left) and usually does not cross the midline. In some cases, the rash may affect adjacent dermatomes (an area of skin supplied by a single spinal nerve) and, rarely, it may affect three or more dermatomes (a condition called disseminated zoster).

Even after the rash has disappeared, some may experience a condition called postherpetic neuralgia (PHN), a nerve pain that can persist for many years. Other complications of herpes zoster include vision loss in patients with infections around the eyes (Herpes zoster ophthalmicus), encephalitis, and an increased risk of stroke and heart attack.

Diagnosis

Doctors diagnose shingles by examining the rashes and blisters.

In rare cases, the doctor may need to test a tissue sample or fluid from the blisters. Testing for antibodies specific to the varicella-zoster virus is done by taking a blood sample. The samples are then sent to a medical laboratory to confirm the presence of the virus.

If shingles appears in the eye area, an ophthalmological consultation is also necessary.

Treatment

Antiviral medications are available to treat shingles and shorten the duration and severity of the disease. These medications are most effective if administered shortly after the rash appears. Self-medication is not recommended.

Pain medications, either over-the-counter or prescription, can help relieve the pain caused by shingles. Compresses, mentholated calamine lotions, and oatmeal baths (lukewarm water mixed with ground oatmeal) can help relieve itching.

Prevention

Vaccination is recommended for the prevention of herpes zoster (shingles) and the long-term neuralgia that can persist after the disease (postherpetic neuralgia). The vaccine is administered as a single dose by subcutaneous or intramuscular injection, preferably in the shoulder area. In patients with bleeding disorders, the vaccine is administered subcutaneously.

Shingles vaccination is recommended for all healthy adults aged 50 or older, as well as adults aged 19 or older who have a weakened immune system due to an illness or treatment. In children, the vaccine can be administered starting at the age of 9 months.

The vaccine is contraindicated in people with immune system disorders, who either have a disease such as leukemia, lymphoma, acquired immunodeficiency syndrome (AIDS), or are taking medications that affect the immune system. Its administration is also contraindicated in patients with active untreated tuberculosis or in pregnant women.

References
https://my.clevelandclinic.org/health/diseases/11036-shingles
https://www.healthline.com/health/shingles
https://www.healthdirect.gov.au/shingles
https://www.medicinenet.com/shingles_herpes_zoster/article.htm
https://www.medthority.com/specialty/infectious-diseases/herpes-zoster/
https://www.ema.europa.eu/en/documents/overview/zostavax-epar-summary-public_ro.pdf
https://bioclinica.ro/pentru-pacienti/boli-infectioase/zona-zoster-cauze-simptome-transmitere-si-tratament
https://www.medicover.ro/despre-sanatate/zona-zoster-simptome-manifestari-tratament,214,n,295
https://www.catena.ro/zona-zoster-de-la-a-la-z