How Chickenpox Causes Shingles (Herpes Zoster)

Jun 23, 2010
Diane Ursu

Picture of Shingles: Herpes Zoster - Renee Gordon

After an episode of chickenpox, the varicella-zoster virus lies dormant in nerves and may later develop into shingles (herpes zoster).

Painful, itchy, burning pustules form on the skin as a red rash. The rash can develop anywhere on the body, but only on one side, such as the right or the left, as if a line is drawn down the middle of the body through the nose and belly button and spine. The pustules ooze and crust over until they clear up within 10 days to one month, but pain can last for months or even years.

This nasty rash may accompany flu-like symptoms, such as body aches, fatigue, a headache, and fever. According to the Mayo Clinic, the pain "can sometimes be mistaken for a symptom of problems affecting the heart, lungs, or kidneys. Some people experience shingles pain without ever developing a rash." The September 4, 2009 Mayo Clinic article, "Shingles," (accessed June 23, 2010) explains that the rash could develop on one side of the face, around an eye, or even wrap around the body on one side from the spine to the breastbone.

Varicella Zoster May Cause Herpes Zoster

Shingles is a name given to the varicella-zoster virus, also called the Human herpesvirus 3 (HHV-3). The first active varicella-zoster virus infection is in the form of chickenpox, an infection that is usually contracted in childhood. Chickenpox produces itchy pustules and flu-like symptoms in addition to abdominal pain and changes in appetite.

The body produces several types of antibodies to fight the infection. The IgG antibody exists throughout one's life and is responsible for producing immunity to chickenpox. In his May 17, 2010 eMedicine article, "Chickenpox," (accessed June 23, 2010) Anthony J. Papadopoulos, M.D., explains that the varicella-zoster virus is believed to move into local sensory nerves where the virus remains dormant. Local sensory nerves carry impulses to the brain from nerve receptors such as those in the skin that receive stimuli, including touch and heat.

Shingles Rash is Unilateral

A nerve extends from the spine to a specific area on one side of the body. The reactivation of the varicella-zoster virus usually occurs in one nerve, so shingles occurs in one region and on one side of the body following the nerve path.

Antigens and Antibodies

The varicella-zoster virus minimizes the expression of proteins on the surface of the virus. These proteins are called antigens because they are unique molecules that the immune system recognizes and acts upon to destroy familiar infections.

If the immune system does not recognize an infection, it produces new antibodies that match the antigens. When an antibody recognizes an antigen, it attaches to the antigen and destroys the foreign body. By not expressing certain proteins while dormant, the varicella-zoster virus decreases the likelihood of being found and destroyed by antibodies.

It is unclear why varicella-zoster virus reactivates later in life to cause shingles, or herpes zoster. Researchers suspect that lessened immunity may be caused by factors that suppress immunity, including certain types of cancer, HIV, and the use of immunosuppressing drugs. It is important to note that only those who have contracted chickenpox are at risk for shingles.

Source

"Recent Advances in Varicella-Zoster Virus Infection," Annals of Internal Medicine (Accessed June 23, 2010)

Diane Ursu - Diane Ursu joined Suite101 as a contributing writer in August 2009 and became a Feature Writer in January 2010. She is a freelance writer ...