What is Chickenpox?

Chickenpox is a very contagious infection caused by the varicella-zoster virus. It mainly affects kids, but adults can get it, too. The telltale sign of chickenpox is a super-itchy skin rash with red blisters. Over the course of several days, the blisters pop and start to leak. Then they crust and scab over before finally healing.

person with chickenpox on backSymptoms appear within 10 to 21 days after you’ve been in contact with someone who has the virus.  Most people recover in about 2 weeks.

Chickenpox is generally mild, especially in children. But in severe cases, the blisters can spread to your nose, mouth, eyes, and even genitals.

Who Gets It?

Children under the age of 2 are most at risk for chickenpox. In fact, 90% of all cases occur in young children. But older kids and adults can get it, too. 

You’re more at risk for chickenpox if you:

  • Haven’t had the virus before
  • Haven’t been vaccinated for it
  • Work in a school or child care facility
  • Live with children

How Is It Spread?

Very easily. You can get the virus by breathing in particles that come from chickenpox blisters or by touching something on which the particles landed.

Chickenpox is most contagious from 1 to 2 days before the rash appears until all the blisters are dried and crusted.

The best way to prevent the spread of the virus is to get the varicella vaccine. Children who’ve never had chickenpox should get two doses of the vaccine -- the first at 12 to 15 months of age, and the second at 4 to s6 years. People over age 13 who’ve never been vaccinated should get two doses of the vaccine at least 28 days apart.

Complications

Adults have a higher risk for developing complications from chickenpox than children. Those with weakened immune systems due to cancer, HIV, or another condition are also at risk.

Once you’ve had chickenpox, the varicella-zoster virus stays in your nerve cells for years. It can “wake up” and become active again years later. It can lead to shingles, a condition that causes painful blisters. Fortunately, there’s a vaccine for shingles. Doctors recommend it for adults over 60.

WebMD Medical Reference Reviewed by Dan Brennan, MD on March 24, 2017

Sources

SOURCES:

PubMed Health: “Varicella (Chickenpox).”

MedlinePlus: “Chickenpox.”

National Foundation for Infectious Diseases: “Facts about Chickenpox for Adults.”

KidsHealth: “Chickenpox.”

New York State Department of Health: “Chickenpox.”

CDC: “Chickenpox (Varicella).”

Mayo Clinic: “Chickenpox.”

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