Shingles is a viral infection, the first symptom of which is usually a tingling, sharp, burning pain under the skin. This is followed 1 - 14 days later by a red rash and blisters. Early treatment can help to shorten the duration of infection and reduce the risk of complications. Vaccination can help to reduce the risk of developing shingles.
Shingles is caused by the same virus as chickenpox. After a bout of chickenpox the virus remains in the body for life and can be reactivated at a later stage as shingles. Anyone who has had chickenpox can go on to develop shingles.
Signs and symptoms
Shingles can occur at any age but usually occurs in adults over the age of 50 years. Females appear to be more frequently affected than males. Groups at an increased risk of developing shingles include people whose immune systems have been impaired due to ill health, medications or diseases that lower the immunity.
The initial tingling, sharp, burning pain under the skin can occur anywhere on the body but usually affects the face, upper abdomen or back. It almost always occurs on one side of the body only. The pain can be mild or it can be quite severe. The older the person is, the more severe the pain is likely to be. Pain can be accompanied by other symptoms including:
- A feeling of being generally unwell
- Mild chills and fever
- An upset stomach
- Enlarged lymph nodes.
After 1 - 14 days a red rash appears over the painful area of skin followed quickly by the development of small, fluid-filled blisters. The rash can be quite itchy. Within a few days of appearing the blisters dry and crust over. It is possible for the blisters to cause mild scarring.
Because shingles affects the nerve cells it is common for the rash to appear as a band across the body or down the leg along the path of a nerve. Occasionally the rash does not eventuate after the initial pain has developed. The pain and other symptoms of shingles gradually resolve as the skin rash and blisters disappear. Full recovery from the condition usually occurs within 2 - 3 weeks, or up to 4 weeks in older adults.
Only people who have had chickenpox in the past (usually in childhood) can get shingles. The reason why the chickenpox virus reactivates as shingles is not fully understood. It is thought that the following factors influence the development of shingles:
- Emotional stress
- Lowered immunity eg: due to medications or chemotherapy that suppress the immune system
- A recent illness or major surgery
- Injury or sunburn to the skin
- Older age.
However, in most people there is no identifiable cause for shingles occurring.
A doctor is usually able to make a diagnosis of shingles based on its characteristic symptoms. A full medical history will be taken and the doctor may take a sample of the fluid from within the blister so that it can be tested in a laboratory for presence of the chickenpox virus.
As shingles is caused by a virus and cannot be cured with antibiotics, treatment focuses on relieving symptoms. Getting adequate rest is an important factor in the treatment of shingles. Other treatment may include:
- Pain relief medications such as paracetamol
- Cool compresses applied to the affected area
- Lotions and creams may be prescribed for the rash
- Antiviral medications may be prescribed. They don't kill the virus but can help to reduce the duration of the symptoms
- Corticosteroids medications may be prescribed if the rash and pain are severe
- Antibiotics may be required if the skin rash develops a bacterial infection.
If the shingles rash has affected the eyes, treatment by an ophthalmologist (eye specialist) may be required to prevent damage to the cornea (the transparent part of the eyeball that covers the iris and pupil).
The virus that causes shingles is present in the fluid within the blisters of people suffering from shingles. Transmission of this virus mainly occurs through direct or indirect contact with the fluid in the blisters. Rarely, the virus can be transmitted in droplets of saliva from the nose and mouth.
A person with shingles is contagious from when the blisters first develop until after all of the blisters have crusted over. If the virus is transmitted from a person who has shingles to a person who has not had chickenpox, that person will develop chickenpox, not shingles.
The most common complication of shingles is a condition called post-herpetic neuralgia. Symptoms include persistent pain at the site of the shingles rash that lasts for more than one month. Anti-seizure and anti-depressant medications are sometimes used to treat the pain caused by post-herpetic neuralgia. Other less common complications of shingles include:
- Bacterial skin infections
- Harm to anunborn foetus if the mother develops shingles in the early months of pregnancy
- Damage to the eye if shingles affecting the eye is left untreated. In rare cases, blindness can occur
- Ramsay Hunt's syndrome caused by facial shingles. This condition can cause ear pain, facial paralysis, and loss of taste and hearing.
Most complications of shingles are very rare, but it is still important to consult a doctor as soon as shingles is suspected so that an accurate diagnosis and appropriate treatment can be given. This is especially important for those people with a weakened immune system.
Prevention / vaccination
Although shingles is less contagious than chickenpox, you should still take the following steps to prevent spreading the virus:
- Keep the rash covered
- Avoid scratching or touching the rash
- Wash your hands thoroughly and often
- Avoid contact with people at risk, including women who are pregnant, premature or low birth-weight babies, and people with weakened immune system.
A shingles vaccine is available in New Zealand for immunisation of people aged 50 years and older and free from GPs for adults at age 65 years. The vaccine reduces the risk of shingles developing and may help to reduce the severity and duration of shingles if it does occur.
If you believe you may have shingles or you want to know if the shingles vaccine is suitable for you, contact your GP or practice nurse, or call Healthline on 0800 611 116 (24 hours a day, 7 days a week).
Immunisation Advisory Centre (2018). Herpes zoster (shingles) Fact Sheet (PDF). Auckland: University of Auckland. http://www.immune.org.nz/sites/default/files/resources/Written%20Resources/DiseaseHerpesZosterImac20180426V02Final.pdf
Mayo Clinic (2018). Shingles (Web Page). Rochester, NY: Mayo Foundation for Medical Education and Research. https://www.mayoclinic.org/diseases-conditions/shingles/symptoms-causes/syc-20353054 [Accessed: 18/06/19]
Ministry of Health (2018). Shingles (Web Page). Wellington: New Zealand Ministry of Health. http://www.health.govt.nz/your-health/conditions-and-treatments/diseases-and-illnesses/shingles [Date Accessed: 18/06/19]
Oakley, A. (2015). Herpes zoster (Web Page). Hamilton: DermNet New Zealand. https://www.dermnetnz.org/topics/herpes-zoster/ [Accessed: 18/06/19
Reid, J.S., Ah Wong B (2014). Herpes zoster (shingles) at a large New Zealand general practice: incidence over 5 years. N Z Med J. 2014;127(1407):56-60.
O’Toole, M.T. (Ed.) (2017). Herpes zoster. Mosby’s Dictionary of Medicine, Nursing & Health Professions (10th ed.). St Louis, MI: Elsevier.
Last Reviewed – June 2019
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