Definition and Overview
Herpes zoster, also known as shingles, is an infection of a nerve area due to the reactivation of the varicella zoster virus; the same virus that causes chickenpox. This viral infection causes pain in the affected area and rashes along the band of skin where the affected nerve lies. Shingles can affect anyone who has had chickenpox in the past. Although it can occur at any age, it is most common in individuals over 50 years old. It is important to note that herpes zoster is very different from genital herpes, which is caused by the herpes simplex virus.
Causes and Risk Factors
Once you recover from chickenpox, the varicella virus does not completely go away but continues to live on dormant in your nerve tissues. While dormant, they do not cause any harm to the body or cause any symptoms. However, for reasons that continue to be unclear, the virus can reactivate and multiply again, often years later. The virus travels along the nerves, causing shingles.
Often, a herpes zoster episode happens for no obvious reason. However, it has been found that certain factors can put you at risk of developing the condition and these include:
- being aged 50 or older
- contracting chickenpox within their first year of life
- weakening of the immune system due to chemotherapy or cancer treatment
- having a disease that weaken the immune system, such as cancer or HIV
- intake of drugs that weaken the immune system, such as medication for organ transplant and steroids
- having a compromised immune system due to stress or previous viral infection such as colds or flu
Although there are rare cases when two to three nerves located beside each other are affected, the reactivated varicella virus usually affects only one nerve on one side of the body. The symptoms then occur in the area where the nerve is located. The nerves commonly affected are those that are supplying the skin on the abdomen (thoracic nerve) and upper face (trigeminal nerve). Shingles can be categorized based on the nerve area affected, and some common terminologies to describe them are as follows:
Geniculate zoster (also called the Ramsay Hunt syndrome)
Ophthalmic herpes zoster: shingles that involve the ophthalmic division of the trigeminal nerve that affects the entire eye; in worst cases, this can cause scarring and vision loss
Herpes zoster that affects the second and third divisions of the trigeminal nerve: produces symptoms and lesions in the mouth, ears, larynx or pharynx (termed as intraoral zoster if located inside the mouth)
Herpes zoster starts out as a burning sensation on the nerve paths through which the virus travels. This escalates into uncomfortable localized band of pain, which can range from mild to severe. Some patients describe the pain as dull or gnawing that persists while others report sharp pain that comes and goes.
The rash starts to show 2 to 3 days after the pain, which appears as red, rough blotches. The rashes develop quickly into itchy, water-filled blisters that resemble chickenpox on the skin band where the affected nerve is located. Blisters develop for up to a week, after which they dry up, crusts and form scabs, and fade away. Slight scarring may occur, which can fade out with time. Shingles typically go away within 4-5 weeks after the first symptoms appear.
Shingles often occur many years after the chickenpox infection and can be contagious, but only to those who have not had chickenpox before. If you already had chickenpox, contact with someone who has shingles will not cause shingles.
Who to See and Available Treatments
If you suspect a developing shingles, it is important to see a doctor immediately. Once the varicella virus reactivates, the virus can no longer be prevented. However, with immediate medical attention, the outbreak of blisters can be controlled and symptoms properly managed. A general practitioner can provide immediate help once shingles is confirmed. However, you may be referred to specialists such as an EENT (eyes, ears, nose and throat) doctor, an ophthalmologist or dermatologist if the need arises.
A simple physical examination of the rashes and blisters is often enough to diagnose shingles. In rare cases, the doctor may test a sample of the skin or the blister to confirm the presence of the virus.
Treatment for Herpes Zoster
In treating shingles, the main aim is to ease pain and discomfort and prevent complications such as the following:
Post-Herpetic Neuralgia (PHN): a complication where the nerve pain persists even after the rashes are long gone
Skin infection: rashes becoming infected with bacteria
Eye problems: for ophthalmic zoster, inflammation of the front of the eye can cause permanent damage to vision
Doctors often recommend the following to treat shingles:
Painkillers: Depending on the severity of the pain, doctors can recommend painkillers such as paracetamol, anti-inflammatory painkillers, or even stronger painkillers such as oxycodone and tramadol
Antiviral medications: Although anti-viral medicines do not kill the varicella virus, it slows down and stops it from multiplying, limiting the severity of the symptoms. Research has shown that antiviral medications have to be started in the early stages (within 72 hours from the appearance of the rash) to be useful. Antiviral medications include aciclovir, valaciclovir, and famciclovir.
Anti-depressant and anti-convulsant medications: These are prescribed in severe episodes of shingles and bad cases of PHN.
Steroid medications - These medicines are taken for a short period; they help reduce the swelling of the affected area and pain, and can facilitate faster healing of the rash.
Numbing creams, patches or gels such as lidocaine to reduce pain
Antihistamines such as Benadryl to reduce itching
Home treatment including rest, cold, wet compresses, colloidal oatmeal baths as well as the application of calamine lotion to manage itching.
Centers for Disease Control and Prevention. “Shingles Overview—Herpes Zoster.” Available: http://www.cdc.gov/shingles/about/overview.html
- National Center for Biotechnology Information. “Shingles.” (2011, May 25). Available: http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001861/
- National Institute of Neurological Disorders and Stroke. “Shingles: Hope through research.” Available: http://www.ninds.nih.gov/disorders/shingles/detail_shingles.htm
- Sampathkumar P, Drage LA, Martin DP. Herpes Zoster (Shingles) and Postherpetic Neuralgia. Mayo Clinic Proceedings. 2009;84(3):274-280. Available: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2664599/