Shingles (also known as zoster or herpes zoster) is a painful blistered skin rash caused by the reactivation of the virus that causes chickenpox – the varicella-zoster virus.
After a person recovers from chickenpox, this virus remains dormant in the body for life. Many years or decades after a childhood chickenpox infection, the virus reactivates in approximately 1 million Americans every year. The virus then travels along a single sensory nerve that supplies a zone of skin on one side of the body called a dermatome.
The onset of shingles typically involves one to three days of pain, burning, tingling or itching, then blister formation along the affected dermatome. Because pain precedes the rash, the pain may be mistaken initially for some other painful situation. The blisters typically dry up, crust and heal over seven to 14 days.
The varicella-zoster virus is only contagious to people who have never had chickenpox or the chickenpox vaccine, and a newly infected person’s rash would be chickenpox – not shingles.
Shingles can occur in anyone with a history of chickenpox or the chickenpox vaccine, and the majority of people with shingles are relatively healthy. Those at highest risk are people over 50 years of age and people with a decline in immune function. Most people who have shingles will not get it again, although on rare occasions, it can reappear.
The individual lifetime risk of developing shingles is one in three, according to the Centers for Disease Control and Prevention (CDC).
The most common complication of shingles is post-herpetic neuralgia, defined as chronic pain and abnormal sensation that persists long after the rash resolves. Individuals who have more severe initial symptoms and advanced age are more prone to this painful complication. Post-herpetic neuralgia occurs in 40 percent of people with shingles who are older than 60.
If you have shingles around an eye or near the tip of the nose, your doctor will likely refer you to an ophthalmologist to evaluate whether the virus is adversely affecting your eye for aggressive intervention to preserve vision. Other possible complications of shingles include secondary bacterial infection of the skin rash and scar formation.
The CDC recommends a single dose of the live attenuated zoster vaccine known as Zostavax in adults aged 60 or older, whether or not they have had a previous episode of herpes zoster. Zostavax decreases the number of people who get shingles by about 50 percent. Of the people who still get shingles even after the vaccine, two-thirds fewer will be affected by the postherpetic neuralgia pain.
Call and visit your doctor if you think you may have shingles. Prescription anti-viral oral medication like acyclovir, valacyclovir or famciclovir can shorten the length and severity of the acute episode and may help to decrease the likelihood or severity of postherpetic neuralgia if administered in the first 72 hours after symptom onset. The earlier anti-viral treatment is started, the better it works.
Jacquelyn B. Garrett, M.D. is a dermatologist in private practice at Christian Hospital.
