Shingles is caused by the same virus that causes chickenpox.
Shingles causes pain so severere that it can be debilitating and unbearable. This condition, also known as herpes zoster or zoster, affects an estimated 2 in every 10 people. Usually appearing as a rash that starts on one side of the face or body, shingles generally last from 2 to 4 weeks. In severe cases, the pain can persist for months, if not years. Shingles is caused by a virus, according to the Centers for Disease Control (CDC), and is passed through direct contact.
Shingles is caused by the same virus that infects people with chickenpox: the varicella-zoster virus (VZV). The difference between chickenpox and shingles is that shingles is the second eruption of the virus. Varicella-zoster is in a group of viruses that can hide in your nervous system after the initial infection. The virus can lie dormant for years until the immune system is compromised, at which point the reactivated virus enters the nervous system to multiply. Shingles develops in three stages: severe pain or a tingling sensation, an itchy rash and then blisters, which resemble chickenpox.
Stress is considered a factor, although negative life events are only considered an anecdotal risk factor. Also, experiencing distress is known to be a factor in an occurrence of shingles. Trauma or surgery can reactivate the varicella-zoster virus in the affected area, which, in turn, can increase the risk of a shingles' rash appearing in that area.
A shingles outbreak usually only happens once in a lifetime. In some rare cases, people have experienced two and three episodes of the outbreak.
Age and health factors put certain groups of people at higher risk of contracting the varicella-zoster virus that causes shingles. The people most commonly at risk are individuals who fall into one of the following categories:
People suffering from systemic lupus erythematosus (SLE), rheumatoid arthritis, Wegeners granulomatosis, Crohn's disease and ulcerative colitis also are at a higher risk for shingles. These conditions are linked due to the patient's use of immunosuppressive drugs.
Five percent of shingles cases involve children. Also, those who have had chickenpox before they were one year of age are more susceptible to getting shingles before they become adults. Older adults are at risk because they often are not exposed to children carrying the varicella-zoster virus, which in turn causes a loss of opportunity to boost their immunity or prevent virus reactivity. In addition, 5 percent of shingles' sufferers are found to have had an underlying cancer.
The varicella-zoster virus can be passed to someone who has not had chickenpox before. Unlike chickenpox, transmission does not happen by the affected person breathing or coughing on another person. According the Mayo Clinic, the virus is passed through direct contact with open sores of the rash. The person infected will develop chickenpox, not shingles, as this is that person's first exposure to the varicella-zoster virus. Exposure to VZV can be a serious condition to certain groups with immune deficiencies, but for a person with a normal, healthy immune system who has already had chickenpox, the varicella-zoster virus cannot be spread. People with shingles should avoid people who have never had chickenpox, people with weak immune systems, newborns and pregnant women until their shingle blisters have scabbed over. This will help minimize the chance of exposing anyone else to the varicella-zoster virus.
A person is no longer contagious once the rash has crusted over. He or she is also not contagious before the blisters appear or if there is pain present after the rash has disappeared.
The CDC documents that high concentrations of VZV are spread via airborne transmission. Also, there is documentation of transmission by passing the virus from patient to health-care providers in a hospital setting. People are less likely to transmit VZV to people in their household or work setting if their lesions are covered.