What Is Shingles?
Shingles is a viral infection that affects your nerves and their cells, but instead of emerging as a new infection, shingles is a reactivation of another virus. If you had chickenpox as a child (or an adult), you’re at risk for shingles, because the two are caused by the same virus – the varicella-zoster virus (VZV).
Dr. Mary Beth Cole
Following a bout with chickenpox, VZV continues to live in your nerve roots, but lies dormant. You don’t know it’s there, and most people live with VZV and never experience a shingles outbreak. However, since anyone who has had chickenpox can get shingles, 95% of adults are considered to be at risk. Approximately one-third of the U.S. population will develop shingles in their lifetime.
It’s unknown what causes the virus to switch from an inactive state to active, but researchers link the virus directly to advanced age and a weakened immune system. “About half of the cases of shingles occur in adults over the age of 60,” says Dr. Mary Beth Cole, dermatologist with Dalton Dermatology. “As we age, our immune system is more easily weakened by factors like cold or stress. That lowered immunity allows the chickenpox virus to reawaken and present as shingles.”
Not only are older adults more likely to get shingles due to declining immunity, they’re also more likely to have a severe case of the infection. “If a patient’s immune system is very low, it can cause a widespread disseminated rash which, while rare, is significantly more dangerous,” explains Dr. Alycia Cleinman, geriatrician with CHI Memorial Center for Healthy Aging. Those who have HIV or those who have recently undergone cancer treatment, taken long-term steroid medications, or received treatment to prevent rejection of an organ transplant, are especially at risk.
Shingles is not contagious, meaning it can’t be passed through bodily fluid or physical contact. However, chickenpox can be spread by someone infected with shingles. Those who haven’t had chickenpox or the chickenpox vaccine, those with a weak immune system, pregnant women, and newborns should not have any physical contact with someone who has shingles.