What is Chickenpox (Varicella)?
Chickenpox is a very contagious disease caused by the varicella-zoster virus (VZV). It causes a blister-like rash, itching, tiredness, and fever. Chickenpox can be serious, especially in babies, adults, and people with weakened immune systems. It spreads easily from infected people to others who have never had chickenpox or received the chickenpox vaccine. Chickenpox spreads in the air through coughing or sneezing. It can also be spread by touching or breathing in the virus particles that come from chickenpox blisters.
Signs and Symptoms
Anyone who hasn’t had chickenpox or received the chickenpox vaccine can get the disease. Chickenpox most commonly causes an illness that lasts about 5-10 days.
The classic symptom of chickenpox is a rash that turns into itchy, fluid-filled blisters that eventually turn into scabs. The rash may first show up on the face, chest, and back then spread to the rest of the body, including inside the mouth, eyelids, or genital area. It usually takes about one week for all the blisters to become scabs.
Other typical symptoms that may begin to appear 1-2 days before rash include:
- high fever
- loss of appetite
Children usually miss 5 to 6 days of school or childcare due to their chickenpox.
The best way to prevent chickenpox is to get the chickenpox vaccine. Adolescents, and adults should have two doses of chickenpox vaccine.
Chickenpox vaccine is very safe and effective at preventing the disease. Most people who get the vaccine will not get chickenpox. If a vaccinated person does get chickenpox, it is usually mild—with fewer blisters and mild or no fever. The chickenpox vaccine prevents almost all cases of severe disease.
For people with chickenpox at risk of serious complications, call a health care provider if the person
- is older than 12 years of age
- has a weakened immune system
- is pregnant
- develops any of the following:
- fever that lasts longer than 4 days
- fever that rises above 102°F (38.9°C)
- any areas of the rash or any part of the body becomes very red, warm, or tender, or begins leaking pus (thick, discolored fluid), since these symptoms may indicate a bacterial infection
- extreme illness
- difficult waking up or confused demeanor
- difficulty walking
- stiff neck
- frequent vomiting
- difficulty breathing
- severe cough
For people exposed to chickenpox, call a health care provider if the person
- has never had chickenpox disease and is not vaccinated with the chickenpox vaccine
- has a weakened immune system caused by disease or medication; for example,
- People with HIV/AIDS or cancer
- Patients who have had transplants, and
- People on chemotherapy, immunosuppressive medications, or long-term use of steroids
- Is pregnant
Your health care provider can advise you on treatment options. Antiviral medications are recommended for people with chickenpox who are more likely to develop serious disease including
- otherwise healthy people older than 12 years of age
- people with chronic skin or lung disease
- people receiving steroid therapy
- some groups of pregnant women
Treatment at Home
There are several things that can be done at home to help relieve the symptoms and prevent skin infections. Calamine lotion and colloidal oatmeal baths may help relieve some of the itching. Keeping fingernails trimmed short may help prevent skin infections caused by scratching blisters.
Use non-aspirin medications, such as acetaminophen, to relieve fever from chickenpox.
Do not use aspirin or aspirin-containing products to relieve fever from chickenpox. The use of aspirin in children with chickenpox has been associated with Reye’s syndrome, a severe disease that affects the liver and brain and can cause death.
Risk to Travelers
Chickenpox (Varicella) occurs worldwide. In temperate climates, chickenpox (varicella) tends to be a childhood disease, with peak incidence among preschool and school-aged children and during late winter and early spring. In tropical climates, infection tends to occur later during childhood and adolescence, resulting in higher susceptibility among adults than in temperate climates.
Chickenpox (Varicella) vaccine is routinely used to vaccinate healthy children in only some countries, including the United States, Australia, Canada, Costa Rica, Germany, Greece, Korea, Qatar, Saudi Arabia, Spain, Switzerland, United Arab Emirates, and Uruguay. With the implementation of the vaccination program in Canada, substantial declines have occurred in disease incidence, although Chickenpox (varicella) is still endemic. Travelers at highest risk for severe chickenpox (varicella) are infants, immunocompromised people, or pregnant women without evidence of immunity.