About 90 per cent of those under 13 years were fully immunised with two doses of the MMR vaccine - MMR stands for measles, mumps and rubella
This dropped to 80 per cent for those in their late teens and young adults, and people born between 1969 and 1992 might not be fully immunised, de Wet said.
"The free MMR vaccine is very safe and very effective. Only a very small number of people have an adverse reaction whereas getting measles can have serious implications."
One in 10 people needed to be hospitalised and the most serious cases could result in deafness and swelling of the brain, he said.
Dr de Wet urged people to check whether their vaccination doses were up to date.
April Wyatt, 30, from Welcome Bay said she and her family had all been immunised and it was a "no-brainer" that her 15-month-old nephew Ryder Nuttall would also be vaccinated.
Ryder was getting his first dose of the MMR vaccine yesterday, Wyatt said.
"Why wouldn't you get vaccinated?
"It's not only free but it will protect you from getting any these nasty diseases that can make you very sick and in some cases kill you.
"I feel strongly that everyone should take the opportunity to do so," she said.
A Greerton mother, who asked not to be named, said there was only one choice for her.
"I have nothing against the anti-vaccination brigade but it makes total sense to me to protect yourself and your children from this very horrible disease," she said.
A spokesperson from Bethlehem Family Doctors said they had at least half of dozen inquiries in the past week, most from adults checking their immunisation status.
Another Tauranga medical centre confirmed it received a few inquiries.
Head GP Harry Pert at Ranolf Medical Centre in Rotorua said there had been a "modest spike" in inquiries, some asking whether they needed an extra MMR dose.
Pert said the key message was that the vaccine was scientifically proven to be safe and it was the best protection against contracting measles.
Central Health Rotorua's practice nurse team leader Elaine Barrington said: "We've gone from zero to a dozen inquiries a day, most to check their vaccine doses are up to date."
This includes a few adults, a man travelling to the Philippines and a mother of a 12-month-old had booked in to get their baby vaccinated early, she said.
If anyone thinks they or a family member may have measles, they should stay at home and phone their GP, or call the Healthline on 0800 611 116 for advice.
Early symptoms of measles:
Fever, runny nose, sore red eyes and cough.
After three to five days a red, blotchy rash appears on the face and head and then spreads down the body.
Measles is highly infectious and just being in the same room with a patient can lead to infection.
Symptoms usually take 10 to 14 days to start showing.
