It might begin as an itchy rash, tingling or a fever.
Before you know it, "Herpes zoster," commonly called "shingles," has broken out into painful red blisters that can take several weeks to heal over and clear up.
Fortunately, the common condition is preventable with a vaccination that's recommended for everyone over 60 and is prescribed for younger people who are at risk.
There's much more at stake than just tingles, blisters and scabs.
"Though the most common complication is pain, or postherpetic neuralgia, shingles can also cause blindness if the nerve to an eye is affected," says Dr. Greg Stern, Whatcom County health officer. "People with profoundly compromised immune systems can get pneumonia as the virus spreads internally, which can be fatal."
Most people who are middle-aged or older had chickenpox when they were kids. Before vaccines were available for measles, mumps and chickenpox, catching those diseases was pretty much an expected part of childhood. What most people didn't know then was that the chickenpox virus would remain in their bodies, waiting to erupt into shingles as they aged.
"After recovering from chickenpox, the varicella virus, like other viruses in the herpes family, remains dormant and can reactivate, traveling up sensory nerves to the skin the nerves go to, causing shingles," Stern explains.
"Zoster vaccine, a high-dose varicella vaccine, boosts the immunity of older people with dormant varicella infection and keeps the virus contained," he says, "reducing the risk of having shingles and perhaps even more importantly, reducing the severity of shingles if you happen to get it."
Unlike their elders, kids these days benefit doubly when they are vaccinated.
"Varicella vaccine, given routinely to children, cuts down the risk of getting chickenpox and therefore the risk of shingles later in life," Stern says.
Several antiviral medicines can help reduce the length and severity of shingles, according to the Centers for Disease Control and Prevention. To work properly, the medicines must be used as soon as a rash appears, so people who think they have shingles should contact a doctor quickly to discuss treatment.
Also, pain medicine can help to ease the discomfort, and compresses, calamine lotion and oatmeal baths can help to relieve some of the itching, the federal agency reports.
Shingles cannot be passed person-to-person, but the virus can spread to people who have never had chickenpox, putting them at risk for that ailment. To stop the spread of the virus, avoid contact with fluid from rash blisters.
If you have shingles, keep the rash covered, avoid touching the rash, and wash your hands often. Once the rash crusts over, the person with shingles is no longer contagious.
Nearly one-out-of-three of people in the United States will develop shingles, so it's important to understand it and to take measures to avoid it. Here are 10 things to know:
(1) Anyone who has recovered from chickenpox might develop shingles.
(2) The risk of the disease increases as a person ages, with half of all cases occurring at 60 years or older.
(3) There are an estimated 1 million cases of shingles every year in the U.S.
(4) People typically experience one episode of shingles, but some suffer a second or even a third outbreak.
(5) People are at greater risk of shingles if they have compromised immune systems, certain cancers, HIV, or receive immunosuppressive drugs.
(6) Herpes zoster, or shingles, is caused by the chickenpox virus, not by herpes simplex, the virus that causes cold sores and genital herpes.
(7) Before the shingles rash appears, there is often pain, itching or tingling for one to five days.
(8) Shingles usually starts as a painful rash on one side of the face or body that typically scabs over in seven to 10 days and clears up within two to four weeks.
(9) Other symptoms can include fever, headache, chills or upset stomach.
(10) The most common complication is postherpetic neuralgia, a severe pain in the rash area that can persist from a few weeks to years, with the risk increasing with age.
For details about shingles from the Centers for Disease Control and Prevention, see cdc.gov/shingles.
Taimi Dunn Gorman is a Bellingham freelance writer.