Dr de Wet said the myth that vaccines caused autism had been thoroughly debunked and it appeared most people realised this.
It was important to make sure parents got their children immunised, and on time to prevent their catching illnesses that were no longer as common as they once were, but were still serious.
"Certainly some diseases on the schedule are becoming incredibly rare," he said.
"Polio is almost eradicated globally because of high immunisation rates. We just don't see them any more.
"There are only a few countries that have not been cleared of polio. [There are] several other diseases we immunise against that are not an ongoing risk in New Zealand."
Other diseases had not been eradicated for a variety of reasons.
"Waikato has a measles outbreak at the moment. We frequently have someone returning from overseas and brings measles back into New Zealand.
"That's why it's important for people to be up to date."
As the whooping cough vaccine wore off after about 10 years, it was also important for mothers to be re-immunised against whooping cough while pregnant as this helped pass antibodies on to the newborn until the baby was old enough to get its own vaccinations.
About seven in 10 babies who caught whooping cough needed hospitalisation.
"When your immunisation coverage rates are good, it means that if the disease is introduced such as coming from an overseas visitor, they are much less likely to pass it on because people they are likely to expose are likely to be immunised."
Dr de Wet said haemophilus influenzae type b (HIB) was once a common childhood illness and the common cause of other severe illnesses such as meningitis, but since an immunisation was introduced to the national schedule two decades ago, cases had dropped dramatically.
Mum gets her pregnancy jabs
New mum Kristy Zink did not hesitate to get her whooping cough and influenza vaccinations while she was pregnant with Daphne, now 1 week old.
"It just makes sense to me," Miss Zink said.
"It's free, it's available, it's preventative.
"It's like wearing a seatbelt, you don't think you're going to crash but you wouldn't put babies in a car without a carseat, so why go out in the world without the protection that's available?"
Miss Zink said she would have felt guilty if her baby became sick from something that was completely preventable.
"I haven't been put off by scaremongers. Some of the things they say are stupid.
"It's alright to have opinions and that's fine, but when a random person on Facebook is saying you're going to get autism, they aren't health professionals."
