Chickenpox

Varicella is a highly contagious disease caused by the varicella-zoster virus. Varicella can be severe, especially in babies, adults, and people with weakened immune systems. A person can usually only have varicella disease once, however the virus can remain inactive within the body then occur later in life causing a painful rash called herpes zoster (shingles).

Varicella is diagnosed by a history of exposure to the disease, symptoms and appearance of the rash. Sometimes the diagnosis is confirmed by laboratory testing including a blood test and samples taken from blisters.

The first symptoms occur about 10 to 21 days after exposure to the virus and include fever, headache, loss of appetite and tiredness. A few days later a rash appears on the stomach, back, face and scalp and then spreads to the rest of the body. The rash begins as small, red flat spots that develop into itchy fluid-filled blisters. New bumps continue to appear for several days. After the blister breaks, the open sores will crust over to form dry, brown scabs. After rash appears, it takes about five to 10 days for all the blisters to crust over. 

The disease is usually mild in healthy children, but serious complications can develop. These include pneumonia, encephalitis (inflammation of the brain), secondary bacterial infections such as septicemia (infection of the blood) or severe skin infections (necrotizing fasciitis) and death. Varicella infection during pregnancy can cause birth defects and death of the baby.

Varicella spreads easily from infected people to others who have never had chickenpox or received the chickenpox vaccine. The virus can spread in the air through coughing or sneezing. It can also be spread by touching (e.g., sharing food or drinks) or breathing in the virus particles that come from blisters. People are infectious from one to two days before to five days after the rash appears or when the blisters have formed crusts. 

Varicella is highly contagious to anyone who has never had the disease or who has not been fully immunized. 

There is no specific treatment for varicella. Supportive care in hospital may be needed for severe infections, but most people recover at home. Symptoms such as fever may be treated with acetaminophen (Tylenol®) or ibuprofen (Advil®). Itching can be relieved by keeping the skin cool. Ask your health-care provider or pharmacist about using lotions. Keep the fingernails trimmed. Drink plenty of fluids. 

ASA or Aspirin® should NOT be given to children under 18 years of age due to the risk of Reye’s syndrome.

Laboratories, hospitals and health-care providers are required to report cases of varicella to Public Health. Statistics on the number of cases are tracked to monitor the impact of the immunization program and to identify outbreaks. 

The best way to protect against varicella is to be immunized. As part of the New Brunswick Immunization Schedule, varicella vaccine is given at 12 and 18 months of age. There is a catch-up immunization campaign provided through school beginning 2015 until 2023 for adolescents born from 2000 to 2008.

A person with varicella should be excluded from childcare centres, school or work until feeling well enough to return. Covering the nose and mouth when coughing or sneezing, disposing soiled tissues, washing hands well and not sharing eating utensils, food or drinking cups will also help to reduce the spread of infection.

Pregnant women should avoid contact with anyone with varicella or shingles and should see their health-care provider if they have been in contact with someone with these illnesses. Prevention methods must be started as soon as possible to reduce the illness and risk of complications.

For additional information, contact your health-care provider, local Public Health office or Tele-Care 811.