Once you have had chickenpox, you usually develop antibodies to the infection and become immune to catching it again. However, the virus that causes chickenpox, the varicella virus, remains dormant (inactive) in your body’s nerve tissues and can return later in life as an illness called shingles.
It is possible to catch chickenpox from someone with shingles, but not the other way around.
Phase one is characterized by unusual skin sensations and other symptoms. Phase two is marked by the presence of a rash and blisters. Blisters eventually rupture, releasing the virus. These eruptions occur for approximately three to five days. Patients are infectious until the lesions are dried. Phase three consists of pain or other complications after the lesions have healed. Some people continue to experience pain for months or even years after recovering from shingles.
The vaccine is not recommended for post-herpetic neuralgia once it has developed. If you have an active case of shingles, you should wait until the rash disappears.
There are some people who should not be vaccinated with Zostavax, including those who have had a severe allergic reaction to gelatin or the antibiotic neomycin. Other people who should not be vaccinated include:
# Women who are pregnant or breast-feeding (there’s no research on the affects the vaccination could have on a foetus or baby)
# People with a weakened immune system, such as those with HIV/AIDs
# People taking medications that weaken the immune system, such as steroids
# Cancer patients being treated with radiotherapy or chemotherapy
# Those with cancer that affects the lymphatic system or bone marrow, such as lymphoma or leukaemia.
If you have shingles, avoid:
# women who are pregnant and have not had chickenpox before, as they could catch chickenpox from you, which may harm their unborn baby
# people who have a weak immune system, such as someone with HIV or AIDS
# babies less than one month old, unless it is your own baby, in which case your baby should have antibodies (proteins that fight infection) to protect them from the virus
Once your blisters have dried and scabbed over, you are no longer contagious and will not need to avoid anyone.
The blisters (vesicles) that develop as a result of shingles contain virus particles. The virus can be spread through direct contact with the open blisters. If you have not had chickenpox before, you can catch it from direct contact with:
# the fluid from the blisters of someone who has shingles
# something that has the fluid on it, such as bed sheets or a towel
If you have shingles, you are contagious until the last blister has scabbed over. This will usually occur five to seven days after your symptoms started.
From before the time the rash erupts until after it’s healed, you’ll be itchy – in some cases, the rash can be extremely painful. The rash usually lasts about 7 to 10 days and completely disappears after one month. The pain can last for up to 3 months or longer in a very small percentage of people. While you will likely have only one bout of herpes zoster, some people may get it several times.
The rash itself is reddish, with many tiny, fluid-filled blisters. For a few days, the rash spreads, although its extent varies from one person to another. The rash commonly occurs on one side of the trunk of your body as a band of blisters that go from the middle of your back around one side of your chest to your breastbone. The blisters will break, dry out, and then crust over.
When the virus becomes active again, you may get symptoms such as rash, upset stomach, headache, fever, and chills. These symptoms are often preceded by warning signs (the prodrome) such as sensitivity, itchiness, numbness, or pain in the days before the rash appears. The rash produces painful, fluid-filled blisters, and you’ll feel tingling or burning sensations.
When the varicella-zoster virus enters its “quiet” phase after chickenpox, it remains dormant in certain nerves. The shingles rash will break out in the areas of the body connected to those nerve cells. As a result, only one section or one side of the body is often affected. Common sites for the rash include the chest, back, buttocks, neck, and sometimes the face and scalp.