Disease expert Michael Baker warns ‘severe’ measles epidemic likely amid failing immunisation rates

New Zealand’s immunisation rates are at their lowest in 15 years. Photo / Warren Buckland

Public health experts have warned New Zealand is on the brink of a measles epidemic and urgent action is required.

In the latest briefing from the Public Health Communication Centre, top epidemiologist Michael Baker and his co-authors laid out the evidence, showing the country is highly vulnerable to a measles epidemic due to falling immunisation rates, immunity gaps and an increasing risk of imported cases.

The briefing warns an epidemic could result in thousands of cases, hospitalisations, chronic illness and potential deaths, with Baker saying urgent steps are needed to get those who have missed out on vaccination up to date.

“This is alongside work to increase routine childhood coverage, particularly for Māori, Pacific peoples and deprived communities,” Baker said.

Baker warned that New Zealand’s immunisation rates were at their lowest in 15 years, with child immunisation coverage at 2 years of age falling to 83 per cent.

“Even more concerning is the much lower coverage for Māori children at 69 per cent, Pacific children at 81 per cent and 75 per cent for children living in the most deprived neighbourhoods. These levels are far below the 95 per cent target level needed to maintain measles elimination.”

Otago University epidemiologist Professor Michael Baker.

An outbreak would only be caused by infected travellers arriving from overseas, but with international travel returning to near pre-pandemic levels, more infectious cases would inevitably enter the country.

“While we commend the Government announcement for investment in measures to raise vaccination rates with a priority focus on Māori, multiple additional strategies are needed immediately to avoid an epidemic,” Baker said.

General practitioner Dr Mamaeroa David said New Zealand’s immunisation rates were higher in 2019, during the last national measles outbreak, which hospitalised nearly 800 people.

“If we have another epidemic, we are also putting our Pacific neighbours in danger. In 2019, our outbreak spread to Samoa, resulting in 83 measles-related deaths, largely in children younger than 5 years.”

David, a co-author of the paper, said New Zealand needed to use all tools available to support a rapid catch-up in MMR (measles, mumps, and rubella) vaccine coverage.

“These measures include supporting Māori-led vaccination programmes that engage effectively with communities, responding to misinformation and disinformation relating to vaccination, and supporting vaccine delivery in schools and other environments where young people can be reached,” David said.

Public health experts’ advice on measles

• Reduce the risk of imported measles by asking all those travelling to New Zealand and all New Zealanders travelling overseas to check their individual and family measles immunity, and get vaccinated if susceptible or uncertain.
• Rapidly address immunity gaps, with the priority in early childhood education centres, schools, and other institutions where many people mix. For disease control and equity, we need to prioritise immunisation strategies to reach Māori, Pacific, and the most deprived children.
• Use the Aotearoa Immunisation Register (AIR) more widely to track and offer vaccination to all born since 2005 without documentation of two MMR doses.
• Prepare for measles outbreaks across the country, including procedures to ensure safe management of cases presenting in healthcare and educational settings and comprehensive documentation and follow-up of the measles immunity status of children attending ECE (early childhood education) centres and schools.

Benjamin Plummer is an Auckland-based reporter who covers breaking news. He has worked for the Herald since 2022.