HealthInfo West Coast-Te Tai Poutini
Overview of vaccination
Te rongoā āraimate
Getting vaccinated is one of the best ways to protect yourself against many serious diseases.
Antibodies are an important part of your body's immune system. Antibodies are proteins your body makes to fight off infections.
Vaccines work by causing your body to produce antibodies against a particular disease. This means that if you are infected with that disease, these protective antibodies are already in your bloodstream to quickly fight off the germs. Even if vaccinated people do get sick from the disease, they usually get a mild form of that disease. They usually recover faster and are less likely to have serious complications.
Pēpi (babies) are born with immunity to some infections because their mothers' antibodies are passed on to them in the womb. But this immunity does not last long. Pēpi get more immunity from being breastfed. But as they grow, they need vaccinations at specific ages to protect them from many life-threatening diseases.
Vaccine-preventable disease rates have dropped because vaccination is now widespread and common. To prevent the spread (and return) of these diseases, it is vital that tamariki (children) continue to receive vaccinations.
Types of vaccines
- Live vaccines. These contain a weakened form of a bacteria or virus that cannot cause disease. This type of vaccine is not recommended if you are pregnant or have a very weakened immune system. Examples are measles, mumps and rubella (MMR), chickenpox and rotavirus vaccines.
- Dead (inactivated) vaccines. These contain bacteria or viruses that have been killed (inactivated) so they cannot cause disease. If you have a weakened immune system, you can receive them, but they may not be as effective. Examples are polio and hepatitis A vaccines.
- Subunit vaccines. These contain a protein or sugar that is part of a bacteria or virus so they cannot cause disease. Examples include hepatitis B, human papilloma virus (HPV), meningococcal and pneumococcal vaccines.
- DNA/RNA vaccines. These use part of the virus's genetic material to stimulate the body to make an immune response. Examples include COVID-19 vaccines.
Vaccines may also contain other ingredients. These include preservatives and ingredients that help your body respond to the vaccine. The very small amounts of these ingredients do not cause any harm. Learn more about what ingredients are in a vaccine.
Level of protection
Studies have shown that if all recommended doses of vaccines are given, they will protect 80 to 98% (80 to 98 out of every 100) tamariki who are vaccinated. For example, whooping cough (pertussis) vaccine is effective in about 84% of tamariki and the measles vaccine in 90 to 98% of children.
Vaccination is an important part of protecting the community against disease. It helps to lower the spread of serious infections. It also protects pēpi who are yet to be fully vaccinated and people who cannot be vaccinated because they are unwell. About 95% of people in the community need to be vaccinated to protect the whole community against diseases like measles.
A very small number of people who are vaccinated do not develop strong immunity and they may still become ill with one of the diseases. If that happens, they usually have a milder illness than people who have not been vaccinated.
More than one dose of some vaccines is needed for full protection. Booster doses of vaccines may also be needed for some diseases.
Side effects
Most reactions to vaccines are mild, such as fever or redness at the injection site. These reactions show that the immune response is building and the vaccine is working. Very rarely, a serious allergic reaction (anaphylaxis) can happen. This is treatable and occurs soon after the injection. This is why you must wait at your healthcare provider for 20 minutes after your vaccination. If you are worried, contact your general practice team straight away.
Safety
The approved vaccines used in New Zealand are very safe. The following page has more detail about vaccine safety.
HealthInfo recommends the following pages
- Health Information and Services – Immunisations
Information about the benefits of vaccination or immunisation.
- HealthEd – Childhood immunisation
Detailed information about childhood vaccinations and the diseases they prevent.
On the next page: Vaccination safety
Adapted from Healthify He Puna Wairoa as part of a National Health Content Hub collaborative. Last reviewed May 2025.
Sources
See also:
Review key: HIIMM-47872
