Also known as varicella, chickenpox is a virus that often affects children. It is characterized by itchy red blisters that appear all over the body. Chickenpox was once so common it was considered a childhood rite of passage. It is well known that once you have chickenpox, you (almost) never have it again.
Since the chickenpox vaccine was introduced in the mid-1990s, cases have declined.
The varicella-zoster virus causes chickenpox. Most cases occur through contact with an infected person. The virus may be contagious several days before blisters appear, and it remains contagious until all blisters have crusted over. It is spread through saliva, coughing, sneezing, and contact with blisters.
Exposure to the virus through previous infection, vaccination, or immunity passed from mother to newborn (immunity lasts about three months from birth) reduces risk. Anyone who has not been exposed may contract the virus. Risk increases under any of these conditions:
- You have had recent contact with an infected individual.
- You are under 12 years of age.
- You are an adult residing with children.
- You have spent time in a school or childcare facility.
- Your immune system is compromised due to illness or medications.
Clusters of red, fluid-filled blisters appearing all over the body are a sign the illness is chickenpox, rather than another type of virus. Any of the following symptoms may appear before, or during, the outbreak of blisters:
- sore throat
Seek medical care any time you develop an unexplained rash, especially if it is accompanied by cold symptoms or fever. You could be affected by one of several viruses or infections. Tell your doctor right away if you are exposed to chickenpox while pregnant.
Many cases of chickenpox are diagnosed based on physical exam of blisters on your (or your child’s) body. If a diagnosis can’t be made, lab tests will confirm the cause of the blisters.
Most individuals diagnosed with chickenpox will be advised to control comfort while waiting for the virus to pass through the system. Parents will be told to keep children out of school and daycare to prevent spread of the virus. Infected adults will also be told to stay home.
Antihistamine medications or topical ointments may be prescribed or purchased over the counter to relieve itching. If you or your child is uncomfortable, any of these may soothe the skin:
- lukewarm baths
- regular application of unscented lotion
- wearing lightweight, soft clothing
Antiviral drugs may be prescribed to those who experience complications from the virus, or who are at risk for adverse effects. High-risk patients are usually young, elderly, or have underlying medical issues. These antiviral drugs do not cure chickenpox. Instead, they make the symptoms less severe, and make your body more likely to heal faster.
Possible complications of chickenpox include pneumonia and skin infections. These can be treated at home with antibiotics. Hospitalization may be needed in severe cases.
Most cases of chickenpox resolve themselves. Patients usually return to normal activities within one to two weeks of diagnosis. When complications occur, they most often affect infants, elderly patients, patients with weak immune systems, and pregnant women. These groups may suffer from infections of the skin or lungs, arthritis or transient synovitis. Women exposed during pregnancy may bear children with birth defects, including poor growth, small head size, eye problems, and mental retardation.
Once chickenpox heals, most people become immune to the virus, as varicella-zoster stays dormant in the body. In rare cases, it may re-emerge. It is more common for shingles, a separate disorder triggered by varicella-zoster, to present during adulthood. If the patient’s immune system is temporarily weakened (possibly due to advanced age or illness), varicella-zoster may reactivate in the form of shingles.
The chickenpox vaccine prevents chickenpox in 90 percent of children who receive it. The shot should be given when your child is between 12 and 15 months of age. A booster is given between 4 and 6 years of age. Older children and adults who have not been vaccinated or exposed may receive catch-up doses of the vaccine. As chickenpox tends to be more severe in older patients, parents who did not previously vaccinate may opt to have the shots given later.
Unvaccinated individuals can try to avoid the virus by limiting contact with infected people. This can be difficult, as chickenpox can’t be identified by blisters until it has been contagious for days.