The most common complication is infection of lesions with bacteria. Rare complications include lung infection (pneumonia) or brain infection (encephalitis). Children who have weak immune systems, eczema, or recent sunburns have more severe symptoms. Because the virus remains resting (latent) in the parts of nerves that are near the spinal cord (nerve roots) for life, about 1 in 10 adults will get shingles (zoster) when the virus reappears, usually under conditions of stress to the body.
After having chickenpox, a person is usually immune for life, although reinfection is possible.
The chickenpox vaccine has been part of routine childhood vaccinations (at age 12–18 months) since 1995, but many children have still not been vaccinated. About 85% of children who have been vaccinated avoid infection, but even if they do show symptoms, they are generally mild. Most infections occur from March to May.
An early pink-to-red, flat, small spot rapidly becomes bumpy and then blisters with a surrounding halo of redness. The spots usually appear first on the trunk or scalp. Linings of body cavities, such as the mouth or nose (mucous membranes), palms, and soles, can have a few lesions. The average child develops a few hundred blisters, most of which heal without leaving scars. A child who has had the chickenpox vaccine will have far fewer lesions.
The blister is usually described as looking like a dewdrop on a rose petal. The blister area (vesicle) is thin-walled and easily broken. Blisters become cloudy and then crust over, with healing completed within 1–3 weeks. Lesions often occur in 3 or more successive series (crops). Lesions in different stages of development may occur at the same time.
- Oatmeal baths in lukewarm water
- Oral antihistamines (diphenhydramine, chlorpheniramine)
- Clip the child's fingernails
- Apply calamine lotion
- DO NOT USE lotions containing antihistamines or lidocaine, as they are no more effective than the previous measures and might cause allergic reactions later on.
- DO NOT USE aspirin. Use acetaminophen (Tylenol®) or ibuprofen instead.
If there are adults or teens in the household who have never had chickenpox or people with eczema, asthma, or a weakened immune system, have them contact their doctor, as they may require antiviral medication. This usually needs to be done early (during the first day of the rash).
Call your child's doctor if:
- He or she has eczema, asthma, or a weakened immune system.
- The fever lasts more than 4 days or exceeds 102 degrees Fahrenheit.
- Any rash areas look red, swollen, and leak pus.
- He or she has a severe cough, vomiting, headache, drowsiness, confusion, stiff neck, trouble looking at bright lights, or difficulty walking or breathing.