Chickenpox in children

Chickenpox in children

Chickenpox: symptoms, definition, home care, treatment, and prevention



Symptoms

Symptoms may be more severe in infants, teens, and immunocompromised children.
  • Mild fever
  • Fatigue
  • Aches and pains
  • Mild headache
  • Red or pink spots that appear on the stomach, back, neck, or face and may spread to the rest of the body, including the scalp, mouth, nose, ears, and genitals; the spots resemble insect bites and turn into small blisters filled with clear liquid that burst and dry to form a brownish crust
  • Extreme itchiness

See a doctor the same day (at a walk-in clinic or emergency room) if, in addition to the above symptoms, your child:

  • Is under 6 months old
  • Has a fever (temperature over 38.5°C) lasting more than 48 hours, especially if their overall condition deteriorates
  • Gets a fever again around the fourth day of illness
  • Has red, inflamed, or painful skin around the blisters (this is sometimes a sign of a bacterial infection)
  • Has a cough or has trouble breathing
  • Has burning eyes or watery eyes that don’t clear up
  • Exhibits dizziness or a loss of balance, severe pain head or neck pain with or without vomiting, seizures, confusion, or behavioural changes
  • Is immunocompromised and has been in contact with a person with chickenpox or shingles during the infectious period

What is chickenpox?

A child with chickenpox

Chickenpox is a highly contagious infectious disease caused by the herpes zoster virus. It is generally harmless in children. However, babies under the age of 1, teenagers, adults, and people with a weakened immune system are at greater risk of complications from chickenpox.

Chickenpox can leave small scars if the blisters are very large or become infected, similar to impetigo. This is why it’s important not to scratch the spots, even if the itching is intense. Fortunately, serious complications (pneumonia, encephalitis, hepatitis, infectious cellulitis, and invasive streptococcal bacterial superinfection) are very rare.

Once you’ve had chickenpox, you’re immunized against this disease for life. However, immunocompromised children can get it a second time.

The chickenpox virus stays dormant in the body and can reactivate later in life and cause shingles.

According to the statistics, about 4.5 out of every 1,000 adults will develop shingles in their lifetime. This complication also occurs in children who have had chickenpox and, rarely, in those who have been vaccinated.

Age: Children aged 1 to 12 are most commonly affected. Chickenpox is rare in children under 6 months of age.
Duration: 7 to 10 days. The rash usually clears up after 2 weeks.
Infectious period: The disease is most contagious in the two days before the rash appears and, to a lesser degree, until all the lesions have dried and scabbed over (around the seventh day).
How it spreads: Through direct contact with the skin or airborne droplets released when an infected person sneezes or coughs.
Incubation period: From 10 to 21 days, usually 14 to 16 days.

Chickenpox and pregnancy: what to do if you’re not immune to the virus

In pregnant women, chickenpox can lead to a serious infection that can be passed on to the fetus (congenital varicella syndrome). If you have been exposed to the chickenpox virus and are not immune to the disease (have not caught the virus in the past and have not received both doses of the vaccine), seek urgent medical attention to receive a preventive immunoglobulin injection to prevent a serious infection.

Treatment

It’s not always necessary to see a doctor if your child has chickenpox. If you do need to take your child to the clinic or hospital, let the staff know that they may have chickenpox.

Antibiotics are useless against chickenpox, as the illness is caused by a virus. Your doctor may, however, prescribe them in the event of complications (e.g., a bacterial infection).

Care and practical advice

  • To bring down your child’s fever, you can give them acetaminophen (e.g., Tylenol®, Tempra®) as indicated and in the doses recommended for their age and weight.
  • Do not give them ibuprofen (Advil®, Motrin®). This drug may be associated with a higher risk of skin infection in people with chickenpox. Never give acetylsalicylic acid (ASA), such as Aspirin®, to a child or teenager.
  • Give your child lukewarm baths every 3 to 4 hours for the first few days after they develop a rash. To help relieve the itching, you can add colloidal oatmeal powder (e.g., Aveeno®) or baking soda (2 tbsp. in a bathtub filled with about 10 cm of water). After bathing, gently pat your child dry with a soft towel.
  • Apply cold damp compresses or ice to the spots, without rubbing the skin.
  • To relieve severe itching, you can apply a topical analgesic or give your child an over-the-counter antihistamine. Don’t hesitate to ask your pharmacist or doctor for advice.
  • To reduce the risk of infection, clean your child’s skin with a mild, unscented soap. Some antibacterial soaps (e.g., Trisan®) can be useful.
  • If a lesion appears infected, wash it thoroughly and apply an antibiotic ointment (Bactroban®, Polysporin®).
  • Dress your child in soft, lightweight cotton clothing. Avoid wool and rough or synthetic fabrics.
  • Trim and file your child’s nails to prevent them from scratching at their blisters, as they could hurt themself or get an infection. Wash their hands and nails frequently. Have them wear light, comfortable gloves at night so they don’t scratch themself in their sleep. You can also put socks on their hands.

Do I need to keep my child home from school or daycare?

You only need to keep them home for two or three days (just long enough for them to start feeling better), then they can go back to school or daycare.

Prevention

Vaccination is the best way to protect your child against chickenpox. The Canadian Paediatric Society, the Protocole d’immunisation du Québec, and the National Advisory Committee on Immunization recommend that all children aged 12 months and over be vaccinated against chickenpox.

The Quebec vaccination schedule calls for two doses of the chickenpox vaccine. The first dose is given at 12 months, the second at 18 months.

This vaccine is over 94% effective at preventing chickenpox after one dose and over 98% effective after two doses. In the rare case that a vaccinated person gets chickenpox, they will have only mild symptoms.

Apart from vaccination, there are few effective ways of preventing chickenpox. Unvaccinated children who have not already had chickenpox are almost guaranteed to contract the disease after contact with an infected child, regardless of age.

Anyone who hasn’t had chickenpox or hasn’t received both doses of the chickenpox vaccine can receive the vaccine after they’ve been exposed to the virus. It should ideally be given within 72 hours of exposure, and no later than 5 days after exposure. Immune globulin is sometimes administered in cases where the vaccine is contraindicated.

Naître et grandir

Scientific review: Dr. Isabelle Viel-Thériault, pediatrician and infectious disease specialist at CHU de Québec – Université Laval
Research and copywriting:The Naître et grandir team
Updated: June 2025

Photos: iStock.com/bojan fatur and Centers for Disease Control and Prevention

Resources

Note: The links to other websites are not updated regularly, and some URLs may have changed since publication. If a link is no longer valid, please use search engines to find the relevant information.

  • Billeau, Audrey. La Maman infirmière à la rescousse : tous les bobos et les soins des enfants de 0 à 6 ans. Montreal, Les Éditions de l’Homme, 2025, 232 pp.
  • CHU Sainte-Justine. “La varicelle : complications de grossesse chez la mère.” CHU Sainte-Justine. 2018. chusj.org
  • Doré, Nicole, and Danielle Le Hénaff. From Tiny Tot to Toddler: A practical guide for parents from pregnancy to age two. Institut national de santé publique du Québec. inspq.qc.ca
  • Gouvernement du Québec. “Quebec Immunization Program.” Gouvernement du Québec. 2024. quebec.ca
  • Ministère de la Famille du Québec. “Les infections en milieu de garde.” Gouvernement du Québec. 2019. mfa.gouv.qc.ca
  • Canadian Paediatric Society. “Chickenpox.” Caring for Kids. 2021. caringforkids.cps.ca
  • Vekemans, Gaëlle. L’ABC de la santé des enfants. 2nd ed., Montreal, Les Éditions La Presse, 2016, 416 pp.

Sources

  • Freer, Giulia, and Mauro Pistello. “Varicella-zoster virus infection: natural history, clinical manifestations, immunity and current and future vaccination strategies.” New Microbiologica, vol. 41, no. 2, 2018, pp. 95–105. pubmed.ncbi.nlm.nih.gov
  • Public Health Agency of Canada. “Varicella (chickenpox) vaccines: Canadian Immunization Guide.” Government of Canada. 2025. canada.ca
  • Nemours KidsHealth. “Chickenpox.” KidsHealth. 2023. kidshealth.org
  • Kimberlin, David W., et al. Red Book: 2024–2027 Report of the Committee on Infectious Diseases. 33rd ed., American Academy of Pediatrics, 2024, 1261 pp.
  • Ministère de la Santé et des Services sociaux. “Var : vaccin contre la varicelle.” Gouvernement du Québec. 2024. msss.gouv.qc.ca
  • Tebruegge, Marc, et al. “Does the use of calamine or antihistamine provide symptomatic relief from pruritus in children with varicella zoster infection?” Archives of Disease in Childhood, vol. 91, no. 12, 2006, pp. 1035–1036.

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