According to the National Institute of Neurological Disorders and Stroke, 25 percent of Americans contract shingles. With few exceptions, shingles strikes just once before the immune system forces the varicella-zoster virus that causes shingles back into a state of inactivity, known as latency. Recurrent shingles, as the name implies, occurs more than once. Recurrent shingles differs in several key aspects from single-episode shingles.
People with immune system diseases such as AIDS, diseases that affect the immune system such as cancer and those who take drugs that suppress the immune system because of autoimmune disease or organ transplant are most likely to develop recurrent shingles. For people with Hodgkin’s disease, non-Hodgkin’s lymphoma or who have undergone bone marrow transplant, the outlook is particularly bleak, according to Richard J. Whitely, M.D., Professor at the University of Alabama School of Medicine. These people have a 40-percent chance of developing progressive or disseminated shingles, in which the disease attacks all of the skin and often the internal organs.
Shingles results from reactivation of the varicella-zoster virus, the virus that causes chicken pox, within the roots of the sensory nerves. According to the 2008 edition of “Harrison’s Principles of Internal Medicine,” recurrent shingles results from deficits in cell-mediated immunity, the same problem that people with AIDS have, and, sometimes, inability to make sufficient antibodies. The two processes are usually linked because antibody production depends on communication between T-cells and B-cells of the immune system.
Healthy people develop shingles lesions over a period of three to five days. The lesions typically scab over by seven to ten days. People with recurrent shingles often continue to develop new lesions for more then one week. Scabbing may not start until three weeks and complete healing may never occur.
In healthy people, shingles usually produces a painful, blistering rash confined to a single side of the body, usually within the area of a single nerve root. People with recurrent shingles usually develop more blisters, sometimes distributed over several nerve roots. The lesions may resemble a severe burn and become secondarily infected by bacteria.
According to the National Institute of Neurological Disorders and Stroke, 50-percent of healthy people develop a complication known as post-herpetic neuralgia, which is characterized by persistent pain, even after the rash subsides. People with recurrent shingles are more likely to develop post-herpetic neuralgia because of both repeated inflammation to the nerve and more severe inflammation. However, it can be difficult to distinguish post-herpetic neuralgia from pain due to an active episode of shingles when episodes occur frequently.
Doctors treat recurrent shingles with antiviral drugs such as acyclovir, famciclovir and valacyclovir. Patients may have to take antiviral drugs every day to prevent recurrences. When outbreaks occur, patients usually require higher doses or several doses per day to force the virus back into remission. Post-herpetic neuralgia requires several drugs, including antidepressants, anticonvulsants, local anesthetics and, sometimes, narcotics.
In May 2006, the U.S. Food and Drug Administration approved a varicella-zoster vaccine, Zostavax, specifically for people at risk of shingles. The vaccine can help prevent shingles in people over 60 who have not already had the disease. People with immune system problems should ask their doctors whether the vaccine might be right for them. Some people with immune system problems do not respond to vaccines, so the vaccine may not be as effective for these individuals.
- "Harrison's Principles of Internal Medicine, 23rd edition;" A.S. Fauci et al.; 2008.
- National Institute of Neurological Disorders and Stroke: Shingles: Hope Through Research
- National Institute of Neurological Disorders and Stroke: Shingles Information Page
- Food and Drug Administration: Zostavax (Zoster Vaccine Live) Prescribing Information