Chickenpox is a highly contagious disease that’s caused by infection with a virus. Most children with chickenpox develop an itchy rash that lasts for about 10 days. Overall, chickenpox tends to be a mild illness in children. Adults with chickenpox often feel more unwell and they are more likely to develop complications than children.

There are treatments available to ease the symptoms of chickenpox, and a vaccine against chickenpox is part of the routine childhood vaccinations in Australia.

What are the symptoms of chickenpox?

The first symptoms are usually flu-like symptoms, such as a fever, tiredness and loss of appetite. This is quickly followed by a red and spotty rash. The spots quickly develop into fluid-filled blisters that look like pimples.

child with chickenpox

The rash normally starts on the chest, face and back, and then spreads to other parts of the body including the scalp, arms and legs. It is usually very itchy. The blisters dry up and form a crust or scab within about 5 to 10 days.

Some children develop only a few spots while others have them all over their bodies — including in the mouth, eyelids, inside the nose and in the vagina in girls.

Most children start to feel better after about a week.

What causes chickenpox?

Chickenpox is caused by the varicella-zoster virus. The same virus also causes herpes zoster (shingles).

The virus is spread from person to person by sneezing and coughing or by direct contact with an infected person’s blisters. After being infected it takes 10 to 21 days for symptoms to appear (usually symptoms develop after 14 to 16 days).

Chickenpox is less common among children these days because most children are vaccinated against it as part of their routine childhood vaccinations. Since the introduction of the varicella vaccine in Australia in 2005, hospital admissions for chickenpox in children under 15 has fallen significantly.

Can you catch chickenpox from someone with shingles?

Shingles is caused by reactivation of the chickenpox virus. While you cannot catch shingles from another person, you can catch chickenpox from someone with shingles.

Complications

Complications from chickenpox are uncommon in otherwise healthy children. Children with problems with their immune systems or other health problems as well as adults and newborn babies and are at higher risk of complications.

Possible complications include:

  • pneumonia;
  • bacterial skin infections;
  • joint or liver inflammation; and
  • encephalitis (inflammation of the brain), which is a rare complication.

Do chickenpox blisters scar?

If chickenpox blisters are scratched or picked at, they can leave a scar. These are sometimes called pockmarks. If a blister becomes infected it is also more likely to leave a scar.

Children should be encouraged to leave the spots alone and use anti-itch medicines to soothe the itching.

Tests and diagnosis

Most children with chickenpox can be cared for at home. If you are not sure if your child has chickenpox or your child is unwell, see your GP (general practitioner).

Your doctor will ask about your child’s symptoms and whether you’ve been in contact with anyone who has recently had chickenpox. They will also want to know how long your child has had symptoms and whether they are getting worse. They will check if your child has been vaccinated against chickenpox.

Your doctor will examine your child, looking especially at the rash. In most cases the diagnosis can be made based on the symptoms and appearance of the rash. Tests are rarely needed, but fluid from the blisters can be collected and tested for varicella-zoster virus in some cases.

Treatment of chickenpox

Most children can be treated at home with medicines and self-care remedies that help control the symptoms. Sometimes antiviral medicines are needed for severe cases or for children at higher risk of complications.

Treating itch

For some children, the rash may be no more than a passing inconvenience, but for others it can be very itchy and unpleasant.

Asking your child not to scratch will probably fall on deaf ears, however it is worth trying to distract them as much as you can. Cut their fingernails very short and make sure that their hands and fingernails are kept clean. It might be worth putting mittens or cotton gloves on very young children to stop them scratching.

If the rash or sores are very itchy, try a warm (but not too hot) bath with half a cup of baking soda. Your pharmacist or doctor will also be able to recommend some anti-itch preparations. Calamine lotion and cool compresses can also be useful.

Treating pain and fever

Paracetamol can be given as directed to reduce fever. Do not give aspirin or nonsteroidal anti-inflammatory drugs (NSAIDs) to children with chickenpox.

Paracetamol can also help relieve discomfort associated with blisters in the mouth or other areas where local treatments can’t be used.

Staying hydrated

Make sure your child rests and drinks plenty of fluids. Water, soups, other fluids, ice blocks and jelly can be offered. Don’t worry if they don’t eat as much as usual while they are sick.

Antibiotics and antiviral medicines

Chickenpox is caused by a virus, so antibiotics are not needed unless your child develops a bacterial skin infection. Skin infections usually develop as a result of scratching the blisters.

Most children do not need to take antiviral medicines. Antivirals may be recommended for children with complicated or severe chickenpox, or those with lowered immunity. Some children with severe eczema may also need treatment with antiviral medicines to reduce the risk of severe chickenpox and complications.

Antivirals may be prescribed for adults if they can be started soon after the rash appears.

Vaccination

Vaccination against chickenpox is recommended for all children in Australia at 18 months. The vaccine is given as a combined MMRV (measles-mumps-rubella-varicella) vaccine, and is available free of charge as part of the Australian National Immunisation Program Schedule.

An additional dose may be given to increase protection, but this second dose is currently not funded on the National Immunisation Program. The second dose can be given anytime from 4 weeks after the first dose.

Vaccination is also recommended for adolescents aged 14 years and over and adults who have not had chickenpox or who have not had the chickenpox vaccine previously. Two doses of vaccine are required in adolescents and adults for adequate protection.

People who have not been vaccinated may be protected if they get a chickenpox vaccine within a few days of being exposed to the virus. Ask your doctor about vaccination in these circumstances.

Side effects of varicella vaccination

Side effects may include pain, redness and swelling of the skin where the injection was given. Less common side effects include a rash, which usually lasts less than a week, and fever. Febrile convulsions can happen, although this is uncommon.

Does the chickenpox vaccine always work?

Getting vaccinated greatly reduces your chances of getting chickenpox. However, some people do still get chickenpox despite being vaccinated.

Vaccinated children who get chickenpox usually have a much milder form of the illness, with fewer spots and lower fever. They also recover faster than children who have not been immunised.

When can my child go back to school?

Chickenpox is infectious from 2 days before the rash appears until after scabs have formed on all the blisters. This usually takes at least 5 days from when the rash first appeared. Do not send your child to school, preschool or daycare during this time.

You should keep your child at home and away from others until they are no longer contagious. Your child can return to their usual activities when all of the blisters have scabbed over.

Last Reviewed: 24/07/2019

myDr



References

1. Chickenpox (published April 2019). In: eTG complete. Melbourne: Therapeutic Guidelines Limited; 2019 Jun. https://www.tg.org.au/ (accessed Jul 2019).
2. Royal Children’s Hospital Melbourne. Clinical Practice Guidelines: Chickenpox (varicella). http://www.rch.org.au/clinicalguide/guideline_index/Chickenpox_varicella/# (accessed Jul 2019).
3. Australian Technical Advisory Group on Immunisation (ATAGI). Australian Immunisation Handbook, Australian Government Department of Health, Canberra, 2018. Varicella (chickenpox) (updated 23 April 2019). https://immunisationhandbook.health.gov.au/vaccine-preventable-diseases/varicella-chickenpox (accessed Jul 2019).
4. Royal Children’s Hospital Melbourne. Chickenpox (reviewed Feb 2018). https://www.rch.org.au/kidsinfo/fact_sheets/Chickenpox_Varicella/ (accessed Jul 2019).
5. Australian Institute of Health and Welfare (AIHW). Chickenpox in Australia, 2018. https://www.aihw.gov.au/getmedia/30dc6fcd-352f-41b9-9e2f-4b4055630f39/aihw-phe-236_Chickenpox.pdf.aspx (accessed Jul 2019).
6. Australian Government Department of Health. Chickenpox (varicella) (updated 4 Jun 2018). https://www.health.gov.au/health-topics/chickenpox-varicella (accessed Jul 2019).