In 2021, New Zealand again kept its death toll better than pre-pandemic times.

Previous posts have given a recent history of improving mortality in Aotearoa New Zealand, and showed that in the first year of the Covid-19 pandemic, 2020, mortality improvement was given a boost. 

2021-2022 in summary

While the Covid-19 pandemic brought illness and death across the world in 2020, New Zealand was one of very few countries estimated to have negative excess deaths in 2020, that is, fewer deaths than expected.  A significant factor in this reduced mortality in New Zealand was the near absence of influenza in 2020, as closed borders prevented flu getting into the country and lockdown stopped transmission.

In 2021, Aotearoa continued with closed borders and was largely lockdown-free, until August.  The Delta variant was almost defeated, but then Omicron was detected in December 2021. The year was again marked with few Covid-19 related deaths, in stark contrast to other countries.

• In 2020, 24 people died in Aotearoa within 28 days of being reported as a Covid case. In 2021, there were 28 such deaths*. 
• Compare with Ireland and Denmark, two countries of similar population size to New Zealand. Ireland saw 2,460 Covid-19 deaths in 2020 and 3,450 in 2021.  Denmark saw 1,660 in 2020 and 1,600 in 2021**.

Long-term context: lower death rates, improving mortality, living longer

The progression of death rates for the over-50s in New Zealand is shown in the chart below.  The main trend is the steady fall in death rates over time, although there are fluctuations due to seasonal impacts and random variations.If death rates improve steadily over time, each generation will live longer on average than older generations. Life expectancy will improve.  This has been the experience in most developed countries over recent decades until Covid-19 threatened to disrupt the improvement trend.

In New Zealand, StatsNZ published figures in March 2022 showing their latest expectations for future average lifespans by cohort (cohort life expectancies).  These show the trend from generation to generation.  For example, females born in 2020 are expected to live on average 0.8 years longer than their older sisters born in 2011.  For males, the younger brother is expected to gain by 0.9 years on average.

New Zealand mortality improvement generally boosted in pandemic

In the chart above the sudden downturn in death rates at the oldest ages in the first year of the pandemic, 2020 can be seen, with some uptick in 2021.  The following charts show death rates for men and women separately, indexing 2020 and 2021 data to 2019 to focus in on what has happened during the pandemic. The baseline chosen is 2019 – the full calendar year before Covid-19 took hold, consistent with the method used by the Continuous Mortality Investigation (CMI) of the UK’s Institute and Faculty of Actuaries. 

 

For males, the general pattern holds at nearly all ages 50 and over.  While death rates are higher in 2021 compared to 2020, they do not return to pre-pandemic levels. Mortality still improved from 2019 to 2021.

For women, the same picture holds at ages 70 and older, but is mixed at younger ages.  This may be due to random fluctuations, or suggest the pandemic experience had some negative effects on mortality for that group.  However, only for women aged 55-64 years has there been no mortality improvement from 2019 to 2021.

 

The results may be sensitive to choice of baseline.  Using instead a baseline of a five year average 2015-2019 tells a similar story because of the general trend of mortality improvement in New Zealand over that period. A smaller peak for women aged 55-64 is still evident, confirming 2020 as a particularly bad mortality year for that age group.  However, the death rates in that age group in 2019 were notably low, so an increase in 2020 would not be unexpected.

Full story of NZ and global pandemic mortality still to be written

In early 2022, Aotearoa New Zealand is reducing restrictions, and the border is opening.  Case numbers have predictably risen dramatically, but a high vaccination rate and other public health measures are intended to keep hospitalisation and death rates lower than seen elsewhere in the early days of the pandemic. Still, by the end of the first quarter of 2022, the number of deaths recorded as occurring within 28 days of being reported as a Covid-19 case has risen to over 350.

New Zealand has so far got through the pandemic with one of the lowest levels of excess mortality in the world because it held Covid-19 at bay until the population was well-vaccinated.  The full story remains to be written with analysis of data from the next few years.  For now, this post confirms that mortality in New Zealand during the first two years of the pandemic was extraordinarily benign, especially compared to the experience of many other countries. 

 

 

* Not all of these deaths may be related to Covid-19 and Covid-19 may be the underlying cause of, or contributed to, deaths that occur more than 28 days after a person was reported as a Covid-19 case.  Ministry of Health statistics downloaded 22 March 2022 from https://www.health.govt.nz/covid-19-novel-coronavirus/covid-19-data-and-statistics/covid-19-case-demographics

**COVID-19 Data Repository by the Center for Systems Science and Engineering (CSSE) at Johns Hopkins University, ourworldindata.org.  Measure is “Confirmed COVID-19 deaths” which may differ between countries and the actual death toll may be higher.