Chickenpox is a very common childhood infection. It is caused by the varicella-zoster virus. However, newborns, adults, and people with weakened immune systems can become very ill if they develop chickenpox.

Chickenpox begins with a slight fever, tiredness, and feeling unwell. A red, itchy rash develops within 1-2 days. The rash usually starts on the face, stomach, chest or back, and then spreads to other parts of the body. The rash is red, with fluid filled blisters that crust over in 3-5 days. Some people may only get a few spots or groups of spots, while others may develop hundreds of spots.

Symptoms of chickenpox usually develop 2-3 weeks after being exposed to someone with the disease.

You can become infected with the virus if you are within 1 meter (3 feet) of a person with chickenpox who is coughing or sneezing. It can also be spread through contact with the fluid from the rash. Blisters that have crusted over are no longer infectious.

A person with chickenpox is contagious 1-2 days before the rash appears, until the last blister has crusted.

Most children with chickenpox are well enough to return to school within 2-3 days, regardless of the state of the rash. There is no evidence that exclusion from school once a child has been diagnosed slows down the spread within a school or daycare. The risk of spread to other children is greatest the day before the rash appears. The Canadian Paediatric Society recommends a child with a fever, continued development of many new spots, and not feeling well enough to participate in regular activities remain at home.

Chickenpox is caused by a virus, therefore antibiotics are not effective. There are some interventions that may assist with the relief of symptoms:

• You can treat a fever with acetaminophen. Do not use aspirin.
• Calamine lotion and lukewarm baths can help to relieve itching. You can also add ½ cup of baking soda to the water, or an oatmeal bath product purchased from your pharmacy.
• Give plenty of fluids.
• Keep your child calm, cool, and dry. Itching will get worse if your child is warm and sweaty.
• Scratching the rash or picking off the scabs can lead to infections and scarring. Keep fingernails trimmed short.

Immunization for chickenpox is now part of the routine vaccination schedule in Ontario for children, and is free. The vaccination is given when the child is 15 months.

It is usually impossible to prevent the spread to other household members who have not previously had chickenpox. Chickenpox in other family members will usually appear within 2-3 weeks.

Close contacts with weakened immune systems, and pregnant women who have not had chickenpox should speak with their doctor if they have been exposed. Most adults have already had the chickenpox and will not get it again.

After infection with chickenpox the virus remains in your body but becomes inactive. It can be re-activated from stress, poor health or a weakened immune system. When it becomes re-activated, it appears as a painful red rash, usually localized to one area of the body. This is called Shingles.

You cannot get shingles from someone that has it. However, if you never had chickenpox, you can develop chickenpox from being exposed to the fluid of a shingles blister.