Vaccines

How do they work? What types are there? Are they effective?

Key points about vaccines

  • Vaccinations are one of the best ways to protect against many serious infectious diseases.
  • Routine immunisation (or vaccination) programmes protect most of the world’s children from many infectious diseases that previously caused millions of deaths each year.
  • Read about how vaccines work, the different types of vaccines and how effective they are.
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If you’re concerned about immunisation, knowing the facts can help you feel more confident about getting vaccinations for you and your whānau. In the following videos, Dr Keriana Bird discusses commonly asked questions about immunisation. Knowing the facts can help you feel more confident about making sure your child has all their vaccinations.

Immunisation:

  • is one of the best ways to protect your whānau against serious diseases
  • involves a vaccine to help your body's immune system protect you against a disease 
  • is also known as vaccination.


Video: Why immunise?

(Ministry of Health, 2019)


Video: An informed choice

(Ministry of Health, 2019)


Video: Worldwide protection

(Ministry of Health, 2019)

To understand how vaccines work it helps to understand how your immune system works.Your body has a natural defence system called the immune system which makes antibodies that fights off germs that can cause serious disease.

Being vaccinated causes your body to produce antibodies against diseases. This means that if you're infected with a disease later (from someone else with a cough, sneeze, or from their blood) these antibodies are already in your bloodstream to fight off the germs quickly..

Even if vaccinated people do get sick from the disease, they usually get a mild form of that disease, recover faster and are less likely to have serious complications.

Babies are born with immunity to some infections because their mother’s antibodies are passed on to them in the womb, but this immunity doesn't last long. Babies get more immunity from being breastfed and then, as they grow, they need vaccinations at certain times to protect them from many life-threatening diseases. Read more about vaccine-preventable diseases.

In the video below Dr Keriana Bird explains how our immune system works and how getting vaccinated helps protect the whole community.


Video: Immunisation and how it works

(Ministry of Health, NZ, 2020)


Video: How vaccines work

(Queensland Health, Australia, 2020)

There are generally 4 types of vaccines.

Types of vaccines

Live vaccines
  • Examples include:
  • These contain bacteria or viruses that have been weakened so that they can't cause disease, but can cause you to make antibodies. 
  • After vaccination, the weakened vaccine viruses or bacteria grow in the vaccinated person.
  • This small amount of virus or bacteria causes an immune response.
  • Live vaccines are not recommended if you are pregnant or have a very weak immune system from active cancer, leukaemia, lymphoma, HIV or you're taking medicines that can weaken your immune system. 
Dead (or inactivated) vaccines 
  • Examples include:
  • These contain bacteria or viruses that have been killed or inactivated. 
  • They can be safely given to a person with a weakened immune system. However, you may not develop the same amount of protection after vaccination as a healthy person receiving the vaccine.
  • With inactivated vaccines, you usually need many doses to give full protection against diseases.
Subunit vaccines
mRNA vaccines
  • An example is the Comirnaty COVID-19 vaccine (also known as the Pfizer-BioNTech vaccine). 
  • This vaccine doesn't contain any virus or DNA. Instead, it contains mRNA that has instructions for making the spike protein just like the one on the surface of the COVID virus. Then when you are exposed to the COVID virus, your antibodies will recognise the protein and fight the virus.
  • The mRNA from the vaccine doesn't stay in your body, but is broken down shortly after vaccination.

Vaccines may also contain other ingredients, such as preservatives, and ingredients that help your body respond to the vaccine. The very small amount of these ingredients does not cause any harm. Learn more about what ingredients are in a vaccine.

Studies have shown that if all recommended doses of vaccines are given, they will protect 80 to 98% of people who are vaccinated. For example, pertussis (whooping cough) vaccine is effective in about 84% of children and the measles vaccine in 90 to 98% of children.

Vaccination is an important part of protecting the whole community against disease. This helps to prevent serious infections spreading and protects babies who are yet to be fully vaccinated and people who can't be vaccinated because they're unwell.

About 95% of people in the community need to be vaccinated to protect everyone against diseases like measles. 

A very small number of people who are vaccinated don't develop strong immunity and they may still become ill if they have contact with one of the diseases. If that happens, they usually have a milder illness than people who haven't been vaccinated.

More than 1 dose of some vaccines is needed for full protection. Booster doses of vaccines may be also be needed for some diseases for you to stay protected.


Video: I've heard some people still get sick. Does that mean immunisation doesn't always work?

(Ministry of Health, 2019)

When to get immunised

The National Immunisation Schedule(external link) has a list of free vaccinations for different ages. Most vaccines are given to babies and children to build up immunity. Vaccination starts at 6 weeks old.

 

Image credit: Health New Zealand | Te Whatu Ora


Vaccinating on time gives the best protection. Missing or late vaccinations can put your whānau’s health at risk but it’s easy to catch up on any you’ve missed.

Catch-up immunisations are free for all children under 18 years of age. Contact your healthcare provider to find out how you can catch up on vaccinations.

Other vaccines are recommended for people who are at greater risk of certain diseases. This includes people with a weakened immune system because of illness or the medicines they are taking, older people, and people who are travelling overseas where certain diseases are more common.

The following is a list of vaccine preventable diseases. These diseases can cause serious, and sometimes fatal, complications. Vaccination is the best protection against them. Click on the links for more information about each disease. 

Standard childhood vaccinations

Targeted vaccines

Available free to all children under 18 years of age (some have age limits).

Available free to certain high-risk groups, but other people can pay for these vaccines through their healthcare provider if they want them.


If you don't know whether you or your whānau have missed any vaccinations, talk to your healthcare provider. They can check and together you can plan how to ‘catch-up’ on any vaccinations.

Create a personalised immunisation schedule(external link) by entering your tamariki’s date of birth. You can download or print a copy of the personalised schedule to show your healthcare provider

Read more about:


Where and how to get vaccinated

Funded and unfunded vaccines can be given by your doctor, nurse, midwife and some paramedics and pharmacists who have been trained as vaccinators.

Different providers may have restrictions on what vaccinations they can give or the ages of people they can vaccinate. So it’s worth checking with the provider first to see if you or your whānau can get the vaccination needed from them.

There are many different places to get a vaccination. These include medical or health centres, pharmacies, community-based clinics including marae-based clinics, mobile health clinics and mobile vaccination services.

Find out more about where and how to get vaccinated.

These videos are NZSL translations of Healthify pages on vaccines.

Below are videos about:

  • Vaccines and how they work – overview
  • What are the types of vaccines – live
  • What are the types of vaccines – dead or inactivated vaccines
  • What are the types of vaccines – subunit vaccines
  • What are the types of vaccines – mRNA vaccines
  • When should you get vaccinated?
  • Are there any risks to being vaccinated?
  • How effective are vaccines?
  • Where can I get vaccinated?


Vaccines and how they work – overview


(Platform Trust, in partnership with Deafradio and Healthify He Puna Waiora, NZ, 2022)
Visit our vaccines and how they work information.


What are the types of vaccines – live


(Platform Trust, in partnership with Deafradio and Healthify He Puna Waiora, NZ, 2022)
Visit our what are the types of live vaccines information.


What are the types of vaccines – dead or inactivated vaccines


(Platform Trust, in partnership with Deafradio and Healthify He Puna Waiora, NZ, 2022)
Visit our what are the types of vaccines that are dead (or inactivated) information.


What are the types of vaccines – subunit vaccines


(Platform Trust, in partnership with Deafradio and Healthify He Puna Waiora, NZ, 2022)
Visit our what are the types of subunit vaccines information.


What are the types of vaccines – mRNA vaccines


(Platform Trust, in partnership with Deafradio and Healthify NZ, 2022)
Visit our what are the types of mRNA vaccines information.


When should you get vaccinated?


(Platform Trust, in partnership with Deafradio and Healthify He Puna Waiora, NZ, 2022)
Visit our when should you get vaccinated information.


Are there any risks to being vaccinated?


(Platform Trust, in partnership with Deafradio and Healthify He Puna Waiora, NZ, 2022)
Visit our are there any risks to being vaccinated information.


How effective are vaccines?


(Platform Trust, in partnership with Deafradio and Healthify He Puna Waiora, NZ, 2022)
Visit our how effective are vaccines information.


Where can I get vaccinated?


(Platform Trust, in partnership with Deafradio and Healthify He Puna Waiora, NZ, 2022)
Visit our where can I get vaccinated information.

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Credits: Healthify editorial team. Healthify is brought to you by Health Navigator Charitable Trust.

Reviewed by: Angela Lambie, Pharmacist, Auckland

Last reviewed: