New research on childhood vaccination suggests that immunisation coverage is slipping, and that vaccine hesitancy among parents may be partly to blame.
Canterbury University postdoctoral fellow, Lukas Marek, who led the research, said social media had played a part and some parents also wanted to live a more natural life.
He found that family wealth and geography were major factors in determining childhood vaccination rates around New Zealand.
Dr Marek told Morning Report while most of the education runs on the vaccines by the government were focused on deprived areas, there was a need to create awareness in affluent localities too.
"... to remind parents that they are protecting not just their own children but they are protecting the entire community."
It was crucial to provide information to all groups in a manner they could understand, he said.
"People choose to not vaccinate until something happens."
He said it might become too late or there might be a lack of vaccine when parents needed them.
Marek was concerned about people being hesitant to take a vaccine against Covid-19.
"It worries me in a sense that we don't know how the population will respond.
"Our research is focused on children but we have to realise that a vaccine for Covid will probably need to be spread through the entire population, it will be most crucial for our elderly population. It is hard to predict how people will respond to that."
He said the efficacy and the length of immunity of the vaccine would be important factors in determining its uptake.