What is Chickenpox?

Chickenpox is a highly contagious disease, caused by the varicella-zoster virus, which is particularly common in primary school children. Once you have had chickenpox you are protected against re-infection, so it is very unusual to catch it again.

What causes chickenpox?

Chickenpox spreads in the same way as the viruses responsible for colds, flu and other infectious diseases. The virus is contained within droplets of mucus and saliva which are released into the air via coughing or sneezing. These droplets also fall onto objects and surfaces which, when touched, enable the virus to be easily transferred to another person. You only need to be in the same space with an infected person for a short period of time for this virus to spread to you. It's a very contagious infection - about 90% of people who have not previously had chickenpox will become infected when they come into contact with the virus.

Chickenpox has an incubation period - the amount of time after first being exposed to the virus that symptoms begin to appear - of 7 to 21 days. Chickenpox can be caught from someone with shingles (an infection of a nerve and the area of skin around caused by the same varicella-zoster virus as chickenpox) but shingles can’t be caught from someone with chickenpox.

What are the symptoms of chickenpox?

Sufferers develop flu-like symptoms before a rash appears which spreads over the entire body. It starts as a series of small red spots which then develop a blister on top. This blister causes intense itching.  The spots appear on the face and body, underneath the arms, inside the mouth and ears and on the soles of the feet and the palms of the hands.

The blistered spots then dry out and a crust forms on top which falls off after a couple of weeks. However, new clusters of spots usually appear after only a few days following the appearance of the rash so most people have spots which are either blistering or crusting over. The symptoms are worse in adults than children.

How is chickenpox diagnosed?

Chickenpox is characterised by a very typical rash which breaks out over the entire body, forms blisters and then dries out, resulting in scabs which eventually fall off so is usually easy to diagnose. See your doctor if you have a poorly functioning immune system (the body’s defence system), are pregnant or have a newborn baby - it is important that you do this as there is a risk of complications in these cases.

What is the treatment of chickenpox?

There isn’t a cure for chickenpox but there are ways you can ease the symptoms, namely the itchy, annoying rash. If you are the parent of a child with chickenpox then use calamine lotion on the spots to ease the itching. Try to stop him or her from scratching the spots by putting gloves over their hands or keeping their fingernails as short as possible since scratching these spots will help spread the rash and can lead to scarring.

Over the counter painkillers such as paracetamol or ibuprofen will ease headaches, muscular pains and a fever but ask your doctor for advice if your child has chickenpox especially if they are less than 3 months old.

Check with either your doctor or pharmacist if you or your child has asthma or a stomach ulcer as ibuprofen can cause problems in these cases and this also applies if you are pregnant. Take paracetamol instead and see your doctor as you may need antiviral medication.

Aciclovir is an antiviral medicine that is sometimes given to people with chickenpox. It may be prescribed to pregnant women, adults (if they visit their doctor within 24 hours of the rash appearing, newborn babies and people with a weakened immune system. Ideally, aciclovir needs to be started within 24 hours of the rash appearing. It does not cure chickenpox, but it makes the symptoms less severe. You normally need to take the medicine as tablets five times a day for seven days.

Wear loose cotton clothing to prevent irritation to the skin and keep drinking fluids. Fluid intake is particularly important for children as they are at greater risk of dehydration so ensure that your child drinks plenty of water and other fluids.

If you have chickenpox, stay off work and at home until you're no longer infectious, which is until the last blister has burst and crusted over. This usually takes five or six days after the rash begins.

If you have, or your child has chickenpox, you may not be allowed to fly until six days after the last spot has appeared. You and your child should be safe to fly once you're past the infectious stage and all of the blisters have crusted over. Check the policy of your airline first though and inform the airline as soon as chickenpox is diagnosed.