HealthInfo West Coast-Te Tai Poutini
Vaccination safety
Te haumarutanga rongoā āraimate
All vaccines used in New Zealand have been thoroughly tested to be sure they are safe. While vaccines can cause a reaction, most reactions are short-lived and minor such as a fever or sore arm.
It is rare to have a serious reaction following a vaccination. You are far more likely to be seriously injured by a vaccine-preventable disease than by a vaccine. The benefits of vaccination greatly outweigh the risk. Without vaccines many more disabilities and deaths would occur.
Risk of getting the disease
You cannot get the disease from the vaccine. Vaccines stimulate your immune system to produce an immune response similar to a natural infection. They do not cause the disease.
Ingredients
Vaccines do not contain harmful levels of ingredients. They contain tiny amounts of ingredients that make the vaccine safe to store and use. For example, formaldehyde, mercury and aluminium. Everyone is naturally exposed to higher levels in the environment than they get from vaccines. This includes pēpi (babies). Our bodies can clear these ingredients without causing harm.
Natural immunity
Vaccination is a safer choice than naturally acquired immunity. It can save a tamaiti (child) from going through a serious illness.
Natural immunity occurs when you have to fight off an infection. This is sometimes stronger than vaccine-acquired immunity. But the risks of this approach far outweigh its benefits.
For example, to develop natural immunity to measles a tamaiti would need to catch measles first. But measles can cause many uncomfortable symptoms. It can also lead to serious complications, including a 1 in 500 chance of death. The MMR vaccine is very safe with the chance of a serious allergic reaction less than 1 in a million.
Vaccines boost your immune system
Vaccination strengthens your immune system by making your body produce antibodies against the disease. This increases your immune response to that disease. This in turn means you are less likely to get it. And if you do get it, you are likely to have a less severe version with fewer complications.
Vaccinated tamariki (children) are less likely to get vaccine-preventable diseases. And they are at no greater risk for other infections.
Several vaccines at the same time
The immune system of even very young pēpi responds to the many bacteria and viruses they come into contact with every day. Having several vaccines at once does not overload their immune system. When they get more than one vaccine in one visit, the vaccines have been tested to ensure they are safe and effective to be given at the same time.
HealthInfo recommends the following videos
- Healthify He Puna Wairoa – Vaccines
A series of videos addressing common questions about vaccines and immunisation.
HealthInfo recommends the following pages
- Health Information and Services – Immunisations
Information about the benefits of vaccination or immunisation.
- Healthify He Puna Wairoa – Immunisation and vaccine topics
Information about vaccines.
Adapted from Healthify He Puna Wairoa as part of a National Health Content Hub collaborative. Last reviewed May 2025.
Sources
Review key: HIIMM-47872
