We have had some confirmed cases of chicken pox in the school. Chickenpox is a common childhood illness caused by a virus. Children with chickenpox need to stay home from school and daycare.

Key points to remember

• chickenpox is a common childhood illness caused by a virus
  
• it is very easy to catch
• most cases of chickenpox are mild and children get better completely
• your child needs to see a doctor if they have a very high fever or are very ill, particularly if they become very drowsy, or are breathing fast or vomiting a lot
• children with chickenpox need to stay home from school and daycare
• chickenpox can sometimes cause serious complications

What is chickenpox?

Chickenpox is a viral illness. The chickenpox virus is also called varicella virus or varicella zoster virus. It is the same virus that can cause shingles, which usually occurs later in life.

Who is at risk of getting chickenpox?

You are at risk of getting chickenpox if you have never had chickenpox and haven't had the chickenpox vaccine.

Chickenpox is more common in children between the ages of 2 and 10 years. If one child in your household gets it, it is almost certain that any others who have never had chickenpox will get it next.

What are the symptoms?

Chickenpox can often start with the following symptoms:

• a fever
• a headache
• a runny nose
• a cough
• loss of appetite
• feeling tired

A red rash follows 1 to 2 days later. It usually starts on the face and scalp, spreads to the chest, back and tummy and then to the arms and legs. It can also appear inside the ears, on the eyelids, inside the nose and mouth, and even around the genital area. The rash continues to spread for 3 or 4 days. It usually becomes very itchy.

Within a few hours after each spot appears, a blister forms. It may appear full of yellow fluid. After a day or so, the fluid turns cloudy. The blisters release liquid containing the virus, then form crusts or scabs that fall off after 1 to 2 weeks. The spots heal at different stages, some faster than others, so your child may have the rash in several different stages at once.

Some children have mild chickenpox with under 50 spots. Others have a miserable time with hundreds of spots.

How is chickenpox spread?

Chickenpox is very easy to catch (it's highly contagious).

The chickenpox virus spreads through the air (by coughing and sneezing) and by direct contact with mucus, saliva, or liquid from blisters. You can catch the chickenpox virus from touching clothing or other objects that have the blister liquid on them.

The incubation period is the time from when your child comes into contact with a person with chickenpox, to when the first symptoms appear. The incubation period for chickenpox is usually 14 to 16 days but can range from 10 to 21 days.

A child is infectious 1-2 days before they get the rash until all the blisters have dried up. This usually takes 5 to 7 days.

Should my child with chickenpox stay home?

Children should stay away from daycare or school, and public places, while they are infectious. Once scabs form on all the spots, your child is no longer infectious. They may go back to school when the spots are all scabbed over and dry. This can take around 5-7 days.

How do I care for my child at home?

• make sure your child drinks plenty of water
• trim nails short and consider using mittens or clean socks to decrease the risk of infection from scratching, especially overnight
• dress your child in loose-fitting clothing and change the bed linen daily
• when blisters in the mouth and throat affect drinking and eating, offer clear cool drinks and soft bland foods - avoid acidic drinks such as fruit juices
• you could try giving your child a cool or lukewarm bath but do not use soap as it can dry out your child's skin. Try adding oatmeal, baking soda or moisturising bath lotion to the water. Pat skin dry, do not rub, after bathing

For many years, people have used calamine lotion to help with the itch from chickenpox and found it may relieve itching. There's really no clear evidence around its use. Calamine is generally considered to be safe although some suggest it may dry the skin too much.

If your child with chickenpox also has eczema, and the above steps are not controlling the itching, you might like to speak to a health professional for advice.

Can I use medicines to relieve chickenpox symptoms?

If your child is miserable because of a fever, headache or other aches and pains, you can give paracetamol to make them more comfortable. You must follow the dosage instructions on the bottle. It is dangerous to give more than the recommended dose.

You should avoid the following:

• aspirin - never give your child or young person aspirin as this may increase the risk of Reye syndrome, which is a rare and serious illness
• ibuprofen (Nurofen, Brufen, Fenpaed) - the use of ibuprofen may be associated with more severe skin and soft tissue infections after chickenpox (particularly necrotising fasciitis, a rare infection of the deeper layers of skin)

Are there likely to be complications?

In the majority of children, chickenpox is a mild illness and they get better completely. Sometimes, scarring from the spots can occur.

There can sometimes be complications which require a hospital stay or intensive care.

The most common complication is a secondary skin infection. Around 1 in 20 healthy children develop a bacterial skin infection which needs treatment with antibiotic medicine. Bacterial skin infections can lead to bacterial infection in other parts of the body, including pneumonia and bloodstream infection (septicaemia).

Other rare complications include:

• encephalitis (brain inflammation)
• severe secondary infections needing intensive care
• death - in very rare cases, children can die of complications from chickenpox

Can chickenpox be prevented?

On 1 July 2017, chickenpox immunisation was added to the National Immunisation Schedule - the series of vaccines that are offered free to babies, children and adolescents, and adults.

That means your child can have chickenpox immunisation at 15 months of age, together with their other vaccines.

Most people who have this vaccine will not get chickenpox. If an immunised person does get chickenpox, it is usually mild.

Your child can also have free chickenpox immunisation if they turn 11 years of age on or after 1 July 2017, if they haven't already had chickenpox or chickenpox immunisation.

Certain high-risk people will still be able to get the vaccine free regardless of their age. Talk to your family doctor or practice nurse.

For more information about chickenpox immunisation, see a fact sheet from the Immunisation Advisory Centre (IMAC) (PDF, 147KB).

Special considerations/precautions

Chickenpox can be more dangerous for certain groups of people who have reduced infection-fighting ability (immunity). The following should see their doctor if they (or you) think they have been exposed to chickenpox, as they may need treatment to prevent chickenpox:

• pregnant women
• newborns
• anyone who is taking long-term oral steroids
• anyone on chemotherapy or who has had an organ transplant
• anyone who is on medication (for example, immunosuppressive medications) which reduces immunity
• anyone who has a condition which reduces immunity (such as cancer or HIV)