Chickenpox in children

Symptoms

• 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

• 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?

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.

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.

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.

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