Vaccine side effects, reactions, and safety
Some people experience reactions from immunisations. These are usually very mild and do not last long. All of the vaccines available in Aotearoa New Zealand have been assessed for safety and effectiveness.
Like most medicines, vaccines can sometimes cause reactions. These are usually mild, and not everyone will get them.
Mild reactions are normal and show that your immune system is responding to the vaccine.
If you’re going to have any reactions, they normally happen in the first few days after getting vaccinated. The vaccine itself is gone from your body within a few hours or days as it gets processed by the immune system.
The most common reaction to an immunisation includes:
- a slight fever
- pain or swelling where the needle went in.
Video: Louis’ parents talk about their anxiety around vaccine side effects
[Kieron] Kia ora, my name is Kieron. This is my lovely partner, Leila and we are both parents of Louis, who is 21 months old.
[Leila] Our son Louis is immunised, he has been immunised up to 15 months.
[Kieron] I was quite keen to have Louis immunised, I trusted in the science.
[Leila] I did have some reservations and some anxiety around Louis being immunised.
I was anxious that putting certain substances into my child when
he was very, very tiny and very vulnerable could have an adverse reaction.
However, that said, I was never not going to immunise him.
He did have a slight reaction to the first lot, just, you know, high temperatures and he was definitely very unsettled.
[Kieron] The response that he had, we were assured by the medical staff that that was, that was normal and that was his immune system kicking into gear.
We got some really good advice from Plunket, we also had visits from kaiāwhina, and our GP was really good as well.
[Leila] Knowing that these are immunisations that we were given that, yeah, they've been around for a long time, was definitely reassuring.
[Kieron] I would just hate for him to to get any one of those illnesses.
Serious allergic reactions are extremely rare. Only about 1 in 1 million people will experience this.
Your vaccinator is well-trained and knows what to look for and can treat an allergic reaction quickly if it happens.
Serious allergic reactions normally happen within the first few minutes of vaccination, this is why you need to wait for up to 20 minutes after immunisation.
Every vaccine has different reactions
At the appointment, your vaccinator will let you know what reactions to look out for. This will help you know what to expect.
For example, some tamariki or adults may develop a fever or a mild rash. This is an expected response after some vaccines, and usually does not last long. It does not mean your child is sick.
If you click on the different vaccines listed on the National Immunisation Schedule you can learn about specific reactions associated with each vaccine.
Some ways you can make your child more comfortable after their vaccination include:
- If their arm or leg is sore from the injection, put a wet cloth or ice pack (wrapped in a dry cloth) on it. Do not rub the injection site.
- If they have a fever, keep your child hydrated. Provide them with lots of water to drink. If breastfeeding, give your child lots of feeds.
- If your child gets too hot, reduce the amount of clothing they are wearing.
- Give your child lots of cuddles.
Give paracetamol or ibuprofen as advised by your doctor, nurse, or healthcare provider.
If you have concerns about symptoms after a vaccine
If you have a concern about a reaction after an immunisation:
- talk to your doctor, nurse, or trusted healthcare provider
- call Healthline on 0800 611 116 anytime
Serious reactions are rare, but can include:
- wheezing, shortness of breath or difficulty breathing
- pinkish, itchy swellings on the skin, also called hives or nettlerash
- swelling of the face, lips, tongue which may cause difficulty in swallowing or breathing, or
- swelling of other parts of the body.
Call 111 and make sure you tell them what vaccine was given.
Reporting side effects
If you, or your child, experience any side effects after a vaccine, you can report them to the Centre for Adverse Reactions Monitoring (CARM).
After access to clean water, immunisation is the most effective health intervention in the world for saving lives.
As well as reducing the risk of getting really sick, there are many other benefits to immunisation.
All vaccines used in Aotearoa New Zealand have been tested for safety and effectiveness.
It’s normal to feel cautious, especially when you’re making a decision about the health of your tamariki, but the benefits to your child of getting vaccinated are much greater than the risks that come with getting the disease if they’re not.