Chickenpox is a common childhood illness characterized by many itchy red bumps all over the body. Before the chickenpox vaccine was invented, 4 million people got it every year, with 11,000 of those people going to the hospital for it and 100 dying from infection, according to the Mayo Clinic. However, since the invention of the chickenpox vaccine and first public vaccination in 1995, those numbers are down significantly, and now 90 percent of people still contract it after being vaccinated, according to the American Academy of Family Physicians.

Symptoms & Causes

Chickenpox is highly contagious and has three stages. It starts out with the appearance of little itchy bumps all over the body that may resemble insect bites. Then, those bumps turn into blisters filled with fluid, followed by the final stage, which is when they scab over, according to the Mayo Clinic. In addition to the itchy bumps and scabs, chickenpox can also cause fever, headache, dry cough or loss of appetite, according to the Mayo Clinic.

The little bumps initially appear on the abdomen or the face in bunches over two to four days, according to the Nemours Center for Children's Health Media. They are less than a quarter of an inch wide (0.635 cm).

Chickenpox is caused by the varicella-zoster virus, which is related to the herpes virus. It is highly contagious, starting two days before the bumps even appear, until the blisters scab over, according to the nonprofit Nemours Center for Children's Health Media. It can be spread by contact with the pox, or by an infected person sneezing or coughing on an uninfected, unvaccinated person.


Children usually have chickenpox without any major issues. However, chickenpox can cause complications for pregnant women, newborns whose mothers weren't vaccinated or haven't had the virus before, teens and adults, people with impaired immune systems and people with eczema, according to the Mayo Clinic.

Complications that can arise include bacterial infection from the pox, though more serious conditions can include pneumonia or encephalitis, according to the Mayo Clinic.

Pregnant women who have never had chickenpox should be especially careful around infected people, especially during their first 20 weeks of pregnancy, according to Nemours. Infection could potentially lead to birth defects in their babies. However, if a woman has already had chickenpox, she will pass chickenpox immunity on to her baby for its first few months.

Even people who have had chickenpox before can develop a similar condition later in life as an adult (and even sometimes in children), called shingles. Shingles, caused by the “zoster” part of the virus, is a painful rash that usually breaks out on one side of the body.

Diagnosis & Tests

Chickenpox is typically diagnosed just by the visible symptoms, according to the Directors of Health Promotion and Education. However, a blood test can also be performed to make completely certain of the diagnosis.

Doctors may also conduct tests in pregnant mothers, newborns, people who are about to undergo organ transplants and people with HIV or AIDS, according to the American Association for Clinical Chemistry. The tests can determine whether you're immune or if you've had a recent infection.

There are two main types of testing: antibody testing and viral testing. Antibody testing looks for the IgM antibody, which is released in response to an infection, according to the American Association for Clinical Chemistry. Antibody testing can also look for the IgG antibody, which is the long-term immunity to chickenpox. Viral testing involves collecting a fluid sample of the pox, testing the DNA on a sample or using a microscope to visualize the infection, according to the clinical chemistry association.

Treatments & Medications

Doctors can prescribe antihistamines to treat the itching symptoms of chickenpox. However, if you fall into one of the high-risk groups mentioned above, a doctor may prescribe an antiviral like acyclovir (under brand name Zovirax) or immune globulin intravenous, known as IGIV, to take within 24 hours of chickenpox symptoms, according to the Mayo Clinic. For adults, valacyclovir (known under the brand Valtrex) or famiciclovir (known as Famvir) may also be prescribed.

Aspirin should never be given to anyone with chickenpox because the medication has been linked to a potentially fatal condition called Reye's Syndrome, which causes organ damage, according to the Mayo Clinic.

There are several home remedies that can help with a typical case of chickenpox. Cool baths, applying calamine lotion, getting rest, eating foods that don't irritate chickenpox sores that may be in or around the mouth and taking acetaminophen (known as Tylenol) or ibuprofen (known as Advil or Motrin), which lower fevers, can all help, according to the Mayo Clinic. It's also important not to scratch to leave scarring.

But perhaps the best way to “treat” chickenpox is to never get it at all. Chickenpox vaccinations are an option for children between the ages of 12 and 18 months, and again between ages 4 and 6 years, according to the American Academy of Family Physicians. It's also encouraged for adolescents and adults, teachers, college students, those in the military, inmates, adult women who haven't yet had children, frequent international travelers and health-care workers who have NOT before had chickenpox to receive the vaccine.

Those who should not receive the vaccine include pregnant women, people who currently have a serious illness, people who have before been allergic to the vaccine, people allergic to gelatin or neomycin, people with lowered immune systems and people who may have had a blood transfusion in the last five months, according to the American Academy of Family Physicians.