By Helen Petousis Harris 10/02/2020

The Ministry of Health has announced a package that might ensure New Zealand will never experience another measles epidemic.

While at the time of writing the details are still limited it appears that the important limitations in our current programme have been acknowledged and the intent is to address them. Great stuff. The commitment is starting with $23 million and more to come.

The proposal to rebuild the immunisation register (NIR) is encouraging. The NIR is not only essential for keeping peoples immunization records but also for helping to identify people and communities that need additional services. Currently this electronic register it is very old and becoming very decrepit. An upgrade to this ailing and vital tool is urgent. Hopefully this will happen soon. It is also a useful tool for conducting vaccine effectiveness and safety studies so as far as I am concerned its function is non-negotiable, we would go back to the dark ages without it.

This is all good news and I am so glad to see this finally happening. It is a shame it took such a terrible epidemic to get this traction. Sadly I have seen this become a political football and blame is being apportioned. I just want to point out that the problems that led to the measles epidemic have evolved over time and are the result of multiple failings that accumulated over nearly three decades (See here for a blog on the fragmentation of NZs public health systems). During this time NZ got the immunisation coverage of our infants from less than 60% to 94%. All governments and stakeholders from the early 90s can take credit for this wonderful achievement, which took over 20 years of policy and practice. This achievement has been much admired internationally.  However, similarly all governments must wear the responsibility for the immunity gaps, sustained over this period.

I have made some diagrams to illustrate the historical context for where we find ourselves today and coloured the associated ‘political landscape’.

Immunisation coverage of two-year-olds in NZ from 1991 to 2016. Original graph depicting policy sourced from UniServices.

Following a devastating measles epidemic in 1991, with 7 deaths NZ realised it had a major problem with immunisation coverage, little more that have of our kids got their vaccines. Basically it sucked. The bottom of the OECD countries. A national embarrassment. In the years 1992 to 2016, there were many strategies implemented to improve this coverage. You can see some of these noted on the graph above. In 1996 another measles epidemic was predicted and this triggered a mass MMR vaccination campaign. Loads of kids in school were vaccinated, although just how many we do not know, there was no NIR in those days.

Things were good for a while then several outbreaks (2009, 2011, 2014) highlighted out immunity gaps, the disease was disproportionately affecting the older kids who had missed out on getting vaccinated. Clearly NZ needed a targeted catch up campaign. Despite the progress in the infant programme, this did not happen. Which brings me to the most recent three years.

Immunisation coverage in NZ two-year-olds from Dec 2009 to Dec 2019.

Every few years we were reminded that we had immunity gaps. Then, in 2017, Auckland experienced a massive mumps epidemic. The gaps in our immunity have never been so glaringly obvious. Also, this highlighted the particular vulnerability of Pacific children and young adults. I personally heard a number of health professionals and stakeholders almost begging for a targeted MMR campaign. At the end of that year, there was limited support provided to address the Auckland mumps epidemic. It came at the end of the year, just before school holidays. However, at least some kids in West Auckland got a dose of vaccine. This same period NZ was awarded measles elimination status by the WHO. It came with a warning. NZ would need to address its immunity gaps as it was still at risk of measles outbreaks.

So here we are in 2020. Addressing our immunity gaps, and maintaining high immunisation coverage of infants will ensure we never see a measles epidemic again.  Maybe addressing the eroded public health landscape is beyond this agenda it is nevertheless a very positive move.