Shingles, also known as zoster or herpes zoster, typically affects almost 1 out of 3 people in the United States. Health professionals estimate that there are about 1 million cases of shingles in this country each year. Whoever recovered from chickenpox can develop shingles later in life. While even children might get shingles, the risk for the disease increases as a person gets older. Most cases affects people 60 years and older.
What is shingles?
Shingles is a disease caused by the varicella zoster virus which is also responsible for chickenpox. The disease is characterized by a painful skin rash with blisters that typically appear in a limited area on one side of the body or face. Once a person has had chickenpox, the virus remains in the nerve cells (dorsal root ganglia) after recovery in a dormant (inactive) state. Year or decades may pass without ever experiencing any symptoms. If the virus does break out, it breaks out of the nerve cells and travels to nerve axons that cause viral infection of the skin in the area of the affected nerve. Normally, the rash heals after a few weeks, but some people suffer from residual nerve pain for months or years afterward, which is called postherpetic neuralgia. The reasons for reactivation of the virus are unknown, but people with weakened immune systems are at greater risk of getting shingles. While herpes zoster and herpes simplex have a similar name, the shingles virus is not the same as the herpes virus. Yet, the Varicella zoster virus and the herpes simplex virus belong to the same viral subfamily Alphaherpesvirinae.
Where does shingles come from?
Shingles has a long recorded history, but physicians and scientists were unable to distinguish this particular disease from blistering caused by smallpox, ergotism, and erysipelas. William Heberden finally accomplished to distinguish between herpes zoster and smallpox in the late 18th century. In the 19th century, herpes zoster was differentiated from erysipelas. In addition, several physicians of the 19th century hypothesized that the disease developed from nerve cell bodies. Yet, the fact that chickenpox and shingles were caused by the same virus was not discovered until the early 20th century. Physicians observed that young people who lived with shingles patients often developed chickenpox later. The connection between the two diseases was finally proven by Thomas Huckle Weller who isolated the herpes zoster virus in 1953. Several studies from the 1960s also showed that the risk for shingles increased with age. A vaccine for shingles was licensed in 2006.
How is shingles transmitted?
First of all, only someone who has had chickenpox – or, rarely, has gotten chickenpox vaccine – can get shingles. Shingles cannot be spread from one person to another. Yet, the virus causing shingles, the varicella zoster virus, can be transmitted from one person to another. This means that while somebody cannot catch shingles from another person with shingles, they can get chickenpox if they have not had chickenpox or the chickenpox vaccine before (however, this is not very common). The virus is spread via direct contact with fluid from rash blisters only. Thus, a person with shingles is infectious once the rash is in the blister phase. The person is not contagious before blisters appear and after the rash has developed crusts. Shingles is less contagious than chickenpox.
What are shingles symptoms?
The symptoms of shingles frequently start with pain, itching or tingling in the area where the rash will develop, typically 1 to 5 days before the rash breaks out. The rash itself, which usually appears in the form of a single stripe on one side of the body or the face, is painful. In rare cases (usually among people with weakened immune systems), the rash may be more widespread and look similar to a chickenpox rash. Shingles can also affect the eye and even cause loss of vision. The rash forms blisters that normally scab over in 7 to 10 days and completely heal within 2 to 4 weeks. Other symptoms may include fever, headache, chills and an upset stomach.
What is the shingles vaccine?
The shingles vaccine is a live, attenuated vaccine that protects against the herpes zoster virus. The zoster vaccine (trade name Zostavax) was introduced in the United States in 2006 and is administered via subcutaneous injection. It was shown to reduce the incidence of shingles by half in adults aged 60 and older. The vaccine has also shown to decrease the number of cases of postherpetic neuralgia and reduce the severity and duration of shingles if the disease does develop in a vaccinated person. Essentially, the zoster vaccine is a larger dose of the chickenpox vaccine (trade names Varivax and Varilrix). Hence, the zoster vaccine protects against both shingles and chickenpox. The zoster vaccine is recommended for adult age 60 and older, including those who have had shingles before and those who do not recall having had chickenpox.
What are the shingles vaccine side effects?
So far, no serious reactions to the zoster vaccine have been reported. The most common side effects include redness, soreness, swelling or itching at the shot site, and headache. Furthermore, there is no documentation of a person getting chickenpox from someone who has received the shingles vaccine (which contains varicella zoster virus). Some people may get a chickenpox-like rash in the area where the shot was given. As a precaution, the rash should be covered until fully healed.
Who should not get the shingles vaccine?
People who ever had a severe or life-threatening allergic reaction to gelatin, the antibiotic neomycin or any other component of the zoster vaccine should not receive the vaccine. People with weakened immune systems such as HIV/AIDS patients, those who are treated with immunosuppressive drugs like steroids, those who are undergoing cancer treatment like radiation or chemotherapy, and those who suffer from cancer affecting the bone marrow or lymphatic system like leukemia or lymphoma should not receive the vaccine. Pregnant women should not receive the vaccine either.
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