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What is chickenpox?

Chickenpox is a highly infectious disease, which causes a blistering rash. Chickenpox is caused by the varicella zoster virus, which is a member of the herpes family.

How is chickenpox spread?

Chickenpox is spread in fine droplets of moisture, which contain the virus. The droplets are produced when the infected person coughs or sneezes, another person then inhales these droplets and may become infected. It can also be spread by direct contact with an infected person.

What are the symptoms of chickenpox?

Chickenpox doesn’t usually make you very ill and the main problem is the itchy blister like rash. This rash usually appears on the scalp or back first, then later may spread all over the body. The rash begins as flat, red spots that become fluid-filled blisters, which will burst, dry and crust over. The average number of blisters is 300, but some people may have less than 10 or more than 1000. Symptoms usually develop 10-21 days after infection. Other symptoms of chickenpox include:

  • Slight fever
  • Loss of appetite
  • Fatigue

Is chickenpox contagious?

Chickenpox is a highly contagious virus, with an incubation period of 15-20 days. Chickenpox is most contagious the day before the rash appears and until the blisters are all dry and crusted over (usually about 5 days). If you have chickenpox you should avoid contact with pregnant women who have not had chickenpox, newborn babies and people with a low immune system (e.g. those with cancer or advanced H.I.V.), as these people can’t fight infection as well as those with a healthy immune system.

How is chickenpox treated?

Chickenpox is a virus and therefore will not be helped by antibiotics. Adults with chickenpox should always consult their doctor. If your child has chickenpox and is not ill, you should ask your pharmacist for advice. Do however phone and tell your doctor that your child has chickenpox, he/she will then decide if they need to see the child.

If you have chickenpox you should try and rest and apply a soothing lotion like calamine to ease the itchiness of the rash. If you or your child has a temperature take paracetamol liquid to bring the temperature down and to relieve any aches and pains.

What are the effects of chickenpox?

Children usually recover from chickenpox without any problems. However in adults the infection may be severe or even fatal, especially in those people with an impaired immune system as they may go on to develop pneumonia. If you develop chickenpox as an adult you should always consult your doctor.

Try not to scratch the spots as this can lead to infection and scarring. Infected blisters look very red and painful and they may ooze a yellow or green fluid. To prevent a child from scratching and causing infection, cut their fingernails and cover their hands with socks or gloves, especially at night.

What is the link between chickenpox and shingles?

Once a person has had chickenpox they will develop an immunity to it and will not contract it again. However, the virus lays dormant in your nervous system and if you had chickenpox as a child it may cause you to develop shingles later in life. You can only get shingles if you have previously had chickenpox.

What is shingles?

Shingles is a painful rash, caused by an inflamed nerve. The actual rash is similar to that of chickenpox though it only affects one side of the body. You may also have headaches and feel very tired and run down. Unlikle chickenpox, shingles is not very contagious, though you should stay away from those who have not had chickenpox.

Call your doctor if:

  • You are an adult with chickenpox.
  • The blisters are infected.
  • You have a temperature over 101ºf (38.3ºc).
  • You have been vomiting.
  • You are pregnant.
  • You have a stiff neck and persistent sleepiness.
  • Your eyes are very sensitive to bright light.