About three in ten people will develop shingles at some point in their lives, most often after the age of 50. It is caused by the same virus as chickenpox — and almost everyone who has had chickenpox carries it.
Why it happens
After a person recovers from chickenpox, the varicella-zoster virus does not leave the body. It lies dormant in nerve cells near the spinal cord. Years or decades later, it can reactivate and travel along a nerve to the skin, causing a painful rash.
Reactivation is linked to a weakening of the immune system, which is why the risk rises with age and is higher in people who:
- are over 50;
- have conditions or treatments that weaken immunity, such as cancer treatment, organ transplants or HIV.
The symptoms
Before the rash. Many people feel burning, tingling, itching or stabbing pain in one area of skin, sometimes several days before anything is visible.
The rash. Red patches appear and develop into fluid-filled blisters, typically in a band or stripe on one side of the body. Over the following days the blisters dry out and form scabs, and the rash usually clears in two to four weeks.
The trunk is the most common site, but shingles can affect any part of the body, including the face.
When the eye is involved
Shingles on the forehead, around the eye or on the tip of the nose can affect the eye itself, causing redness, watering, sensitivity to light and, in some cases, lasting damage. Anyone with a rash in this area should see a doctor promptly.
Treatment
A doctor can usually diagnose shingles by looking at the rash. Antiviral medicines can shorten the episode and reduce the severity, and work best when started within 72 hours of the rash appearing — so it is worth seeing a doctor early. Pain relief is often needed too.
Is it contagious?
You cannot catch shingles from someone with shingles. However, fluid from the blisters can transmit the virus to someone who has never had chickenpox or the vaccine, who could then develop chickenpox. Keeping the rash covered and washing hands helps prevent this.
Lasting pain
Some people continue to have nerve pain long after the rash has healed. This complication, called post-herpetic neuralgia, can last for months or even years and is more common in older people.
Vaccination
A recombinant vaccine offers strong protection against shingles and its complications. In Spain it is offered through the public health system to older adults, according to each region’s vaccination calendar, and to adults with certain conditions that increase their risk. Ask your health centre whether you are eligible.
