Education Materials

Mount Sinai Hospital is a University of Toronto patient care, teaching, and research centre.
Mount Sinai Hospital is a University of Toronto patient care, teaching, and research centre.

Frequently Asked Questions

FAQ: Chickenpox (Varicella) Vaccine

This document has been prepared for educational purposes by Karen Green, RN CIC. Should you have any questions regarding individual health concerns or health care practices, please consult your physician or health care provider directly.

» Why should I get my child vaccinated against chickenpox?

  • Chickenpox (varicella) is a very common and contagious childhood disease. The virus usually causes mild infections in children, but can cause more severe disease in adults. Occasionally, even in healthy children, chickenpox can lead to severe skin infections, pneumonia, brain damage or death.
  • The virus that causes chickenpox is spread from person to person through the air or by direct contact with the fluid from chickenpox blisters.
  • Chickenpox causes an itchy rash which may begin as smooth, red spots which develop into blisters. It is often accompanied by fever and tiredness.
  • Years after having had chickenpox, people can develop a painful rash called shingles.
  • Chickenpox vaccine can prevent chickenpox.

» Can you still get chickenpox after being vaccinated?

  • Most people who get chickenpox vaccine will not get chickenpox.
  • However, because chickenpox vaccine is made from a live, but weakened form of the chickenpox virus, there is a small risk of getting chickenpox after the vaccine.
  • If someone who has been vaccinated does get chickenpox, it is usually very mild, much milder than if they had been infected through natural exposure to the chickenpox virus.
  • They usually have fewer spots, are less likely to have fever and recover more quickly.

» Who should get chickenpox vaccine?

  • All children from 12 to 18 months of age, and children 18 months to 12 years of age who have never had chickenpox should receive one dose of vaccine.
  • Children over the age of 13 or adults who have not had chickenpox or not been vaccinated require 2 doses of chickenpox vaccine, 4-8 weeks apart.
  • Any non-immune health care workers or other adults who work with children or immunocompromised individuals.

» Who should NOT get chickenpox vaccine?

  • Anyone with a life-threatening allergy to gelatin, neomycin or a previous dose of chickenpox vaccine.
  • People with any active infection with fever.
  • Pregnant women. Women should not get pregnant for 3 months following vaccination.
  • People with the following conditions should check with their doctor about whether or not they should have chickenpox vaccine:
    • HIV/AIDS or other diseases affecting the immune system
    • on treatment with drugs that affect the immune system
    • lymphoma, leukemia, blood dyscrasias, or any kind of cancer affecting the bone marrow or lymphatic system
    • active untreated tuberculosis

» Are there any side effects to the vaccine?

  • Most people who get chickenpox vaccine have no side effects. In those who do, the most common side effects are pain, redness or swelling at the injection site.
  • Rarely, vaccines like other medication can cause severe allergic reactions. The risk of chickenpox causing serious harm or death is extremely small. There are fewer risks associated with the chickenpox vaccine that there are with getting chickenpox.
  • If after vaccination, any of the following occur, contact or visit your doctor left away:
    • serious allergic reaction within a few minutes to a few hours (difficulty breathing, horseness, wheezing, hives, paleness, weakness, fast heart beat, dizziness)
    • high fevers, changes in regular behavior, or seizures.

» Where can I get the chickenpox vaccine?

  • Chickenpox vaccine has recently been licensed for use in Canada.
  • If you are considering vaccination for yourself or your child, discuss vaccine options with your family physician or pediatrician.
This website has been made possible through an unrestricted educational grant from Pfizer Canada Inc.
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