CausesBy Mayo Clinic staff
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|Shingles affects the nerves|
Shingles is caused by the varicella-zoster virus — the same virus that causes chickenpox. Anyone who's had chickenpox may develop shingles. After you recover from chickenpox, the virus can enter your nervous system and lie dormant for years. Eventually, it may reactivate and travel along nerve pathways to your skin — producing shingles.
The reason for the encore is unclear. But it may be due to lowered immunity to infections as you grow older. Shingles is more common in older adults and in people who have weak immune systems.
Varicella-zoster is part of a group of viruses called herpes viruses, which includes the viruses that cause cold sores and genital herpes. Because of this, shingles is also known as herpes zoster. But the virus that causes chickenpox and shingles is not the same virus responsible for cold sores or genital herpes, a sexually transmitted infection.
Are you contagious?
A person with shingles can pass the varicella-zoster virus to anyone who isn't immune to chickenpox. This usually occurs through direct contact with the open sores of the shingles rash. Once infected, the person will develop chickenpox, however, not shingles.
Chickenpox can be dangerous for some groups of people. Until your shingles blisters scab over, you are contagious and should avoid physical contact with:
- Anyone who has a weak immune system
- Pregnant women
- Shingles: Hope through research. National Institute of Neurological Disorders and Stroke. http://www.ninds.nih.gov/disorders/shingles/detail_shingles.htm. Accessed June 24, 2011.
- Shingles: Clinical overview. Centers for Disease Control and Prevention. http://www.cdc.gov/shingles/hcp/clinical-overview.html. Accessed June 24, 2011.
- Habif TE. Herpes zoster. In: Habif TP. Clinical Dermatology: A Color Guide to Diagnosis and Therapy. 5th ed. Edinburgh, U.K.; New York, N.Y.: Mosby Elsevier; 2010. http://www.mdconsult.com/books/about.do?about=true&eid=4-u1.0-B978-0-7234-3541-9..X0001-6--TOP&isbn=978-0-7234-3541-9&uniqId=230100505-57. Accessed June 24, 2011.
- Ferri FF. Herpes zoster. In: Ferri FF. Ferri's Clinical Advisor 2011: Instant Diagnosis and Treatment. Philadelphia, Pa.: Mosby Elsevier; 2011. http://www.mdconsult.com/books/about.do?eid=4-u1.0-B978-0-323-05610-6..C2009-0-38600-6--TOP&isbn=978-0-323-05610-6&about=true&uniqId=230100505-53. Accessed June 24, 2011.
- Shingles vaccine: What you need to know. Centers for Disease Control and Prevention. http://www.cdc.gov/vaccines/pubs/vis/downloads/vis-shingles.pdf. Accessed June 24, 2011.
- Albrecht MA. Epidemiology and pathogenesis of varicella-zoster virus infection: Herpes zoster. http://uptodate.com/home/index/html. Accessed June 24, 2011.
- Albrecht MA. Clinical manifestations of varicella-zoster virus infection: Herpes zoster. http://uptodate.com/home/index/html. Accessed June 24, 2011.
- FDA approves Zostavax vaccine to prevent shingles in individuals 50 to 59 years of age. U.S. Food and Drug Administration. Accessed June 24, 2011.
- Zostavax (prescribing information). Whitehouse Station, N.J.: Merck & Co.; 2011. http://www.merck.com/product/usa/pi_circulars/z/zostavax/zostavax_pi2.pdf. Accessed June 24, 2011.