Content Editor

Varicella (chickenpox)

Learn about varicella, who is at risk, and how it spreads.

About varicella

Varicella, also called chickenpox, is a virus that can cause a fever and an itchy rash that looks like small water-filled blisters. It spreads easily through the air by coughing, sneezing, or by touching open blisters.

It is usually mild, but can be more serious in newborns, adults, and people with weak immune systems. People who get varicella can have:

  • skin infections
  • pneumonia (a type of lung infection)
  • blood infections
  • other deadly infections

Learn more about varicella.

After you get varicella, the virus stays in your body. It can become active again and cause shingles (a painful skin rash).

Who is most at risk?

People with the highest risk of serious infections from varicella are:

  • newborns
  • adults
  • people with weak immune systems

How it spreads

Varicella spreads easily through the air by coughing, sneezing, or touching open blisters. You can spread varicella before you get the rash.



Touching open blisters


If you are pregnant and get varicella, there is a small risk of having a baby born with:

  • a low birthweight
  • eyesight problems
  • scars on the skin
  • birth defects (such as poor development of the brain or an arm or leg)

If you get varicella a few days before or after you have your baby, the baby has a high risk of getting very sick or dying.

Current as of: July 1, 2024
Author: Provincial Immunization Program, Alberta Health Services
Our work takes place on historical and contemporary Indigenous lands, including the territories of Treaty 6, Treaty 7 & Treaty 8 and the homeland of the Métis Nation of Alberta and 8 Métis Settlements. We also acknowledge the many Indigenous communities that have been forged in urban centres across Alberta.