Everything you need to know about the chickenpox vaccine

Chickenpox may seem like a harmless childhood disease. But the truth is that chickenpox can sometimes cause serious complications and may lead to shingles later in life. Here, nib Medical Advisor Dr Hamish Black shares everything you need to know about the chickenpox vaccine and why it’s important.  

Chickenpox (also known as varicella) is a highly infectious disease caused by the varicella-zoster virus (VZV). The most common symptom is an itchy red rash with blisters that turn into scabs. Some people also get a fever or headaches. 

While chickenpox is more common in children, it tends to be more severe when adults get it. Most people make a full recovery, but chickenpox can occasionally cause complications, including skin infection, pneumonia, encephalitis (inflammation of the brain) and bleeding disorders. In rare cases, these complications can be fatal. 

The Australian Immunisation Handbook recommends two doses of the chickenpox vaccine at least four weeks apart for: 

• Children aged 12 months to 14 years 

• All non-immune adolescents over the age of 14 and non-immune adults, especially healthcare workers, long-term care facility workers, and childhood carers and educators. 

While the chickenpox vaccine is generally safe and serious side effects are rare, some people shouldn’t get it. These include pregnant women, people who are immunocompromised and those who have had anaphylaxis after a previous dose. Talk to your doctor if you have any concerns about the chickenpox vaccine.  

How does the vaccine work? 

The chickenpox vaccine is a live vaccine containing a small amount of weakened varicella-zoster virus. It stimulates the immune system to produce antibodies against chickenpox.  

“There are two monovalent vaccines [protecting only against chickenpox] and two combination vaccines [protecting against measles, mumps, rubella and varicella] available in Australia for primary immunisation,” says Hamish. “There are also two booster vaccines to help prevent shingles, which is also known as herpes zoster and is caused by a reactivation of varicella-zoster virus.” 

Vaccination for chickenpox is part of the childhood immunisation schedule and is routinely administered [for free] at 18 months of age 

A second dose is recommended to increase children’s protection against chickenpox. Adolescents over 14 and adults who haven’t been vaccinated or haven’t had chickenpox can get two doses of the vaccine at least four weeks apart. 

Do you need a booster? 

“Of those who have had chickenpox, 50% will get shingles,” says Hamish. “Shingles can be severe in older adults and lead to debilitating post-herpetic neuralgia, which is chronic nerve pain. The booster vaccine to protect against shingles is recommended for all adults over age 60 and people over 50 who live with someone who has a weakened immune system. It’s free for people over 70 as a one-off booster.” 

The booster vaccine isn’t recommended for women who are pregnant, people with current or recent severe immunocompromise or people who have had anaphylaxis following a previous dose of the vaccine. Your doctor can tell you whether the booster vaccine is right for you. 

Please note: The tips throughout this article serve as broad information and should not replace any advice you have been given by your medical practitioner.