Analysis by Keith Rankin.
A pandemic can end in three ways. Either the death rates attributed to the pandemic disease cease, or at least drop back to pre-pandemic levels. Or normality is re-established, with the pandemic disease still present, but displacing other causes of death. Or a ‘new normal’ is established, with higher ongoing rates of death normalised.
So, to some extent, a pandemic’s duration is a state-of-mind; meaning that the post-pandemic period is when that ’emergency’ mindset has departed. To a large extent, that happens when the most burdensome public health restrictions become untenable; in New Zealand’s case, that was when the substantive closure of the international border finished. Deaths, covid or otherwise, may still be a problem, but they cease to be newsworthy!
For most of the world, the post-pandemic period started around February 2022. East Asia was the principal exception. Table 1 below shows mortality in the first year of the new normal.
|Table 1: Back to Normal?|
|England & Wales||515610||592677||14.95%|
|*||year ended April 2019|
|**||latest available 12-month period|
Table 1 shows a number of countries’ most recent annual death tallies compared with the year ended April 2019, the best baseline period available. May 2018 to April 2019 was chosen because it represents the first full year after the silent influenza pandemic of November 2016 to April 2018. While not a media event, that largely invisible 2017 pandemic was a substantial mortality event, at least in the ‘global north’. A pandemic does not require an authentication from WHO to be an actual pandemic. A pandemic is simply a globally widespread experience of a disruptive contagious disease.
Broadly, Table 1 shows the countries which followed ‘elimination strategies’ near the top for post-pandemic mortality. Not only did countries in the east of the eastern hemisphere (including Aotearoa New Zealand) pursue the most stringent anti-covid policies (and practiced them for the longest time periods), some prematurely claimed to have eliminated (though not eradicated) the disease. For some in East Asia, the 2003 experience of SARS was uppermost in health officials’ minds.
Table 1 also shows that some of the countries worst-hit by the pandemic (especially those in the Southeast European ‘Balkans’) have returned to death tallies comparable with base-year numbers. If South Africa and Egypt are a suitable guide, that return to health normality applies to Africa as well.
The only West European countries with post-pandemic deaths under nine percent more than pre-pandemic deaths are Sweden and Belgium, both countries with high covid death tallies in the first wave of the pandemic, but well below European mortality averages in the second year of the pandemic. Sweden’s 6.55% increase actually overstates its situation by about two percentage points, because, more than in most other countries, deaths there were particularly and unusually low from May 2018 until the start of the pandemic. Also, Australia’s 16.53% is an overstatement, probably by at least two percentage points; this is because tardy Australia’s most recent annual deaths’ data includes the months of December 2021 and January 2022, both high mortality months compared to the following December and January.
New Zealand’s most recent death data uses December 2022 and January 2023, not December 2021 and January 2022. In contrast to Australia, New Zealand’s Table 1 increased mortality experience is understated by a percentage point, because March and April 2019 (included in the pre-pandemic baseline year) had somewhat higher deaths than those same months in 2018. If we had used a baseline year from March 2018 to February 2019, then New Zealand would have had a mortality increase of 17.40%, not 16.13%.
Re East Asia, the numbers for Macau and Hong Kong give a hint of the recent reality in China. For that region we should note also that the South Korea increase in Table 1 (22.56%) is a substantial understatement of reality, because South Korea has not reported ‘total deaths’ after July 2022, and we know that Korea has had many covid cases since then.
We also note that post-pandemic death tallies are high for Japan, Ireland, Scotland, Iceland, and Finland. These are all countries which, for their regions, were known for their more restrictive public health policies. Finland was widely acclaimed for being the most restrictive of the Nordic countries during the pandemic years. (We also note that Finland had many more deaths than Norway both pre-pandemic and post-pandemic, despite having about the same population as Norway; it suggests that many more young Finns are working abroad than young Norwegians. Likewise, we see that New Zealand has more deaths than Ireland, despite both countries having essentially the same population.)
Germany, which has had a particularly worrying recent run of deaths, in Table 1 is not out of step with its western neighbours; although we should note that southern Western Europe has generally had a post-pandemic more normal than northern Western Europe (Sweden excepted).
The critical question, looking to 2023 and 2024, is whether, for the countries towards the top of Table 1, the pandemic has triggered a new normal with persistently higher mortality than in the 2010s’ decade. Or have these countries simply experienced a delayed pandemic mortality experience which will soon subside? If the latter, then we should expect a substantial mortality drop in East Asia and West Europe in the year to April 2024.
Demography and the challenges of predicting the pandemic’s influence on 2020s’ mortality
Demography is a complex subject. Pandemic death rates per capita were high in Eastern Europe because those countries have lost many of their young people to emigration. Increases in death tallies, however, were never so high in those countries. The demography of Europe is particularly complex because many of their older people were born either side of, or during, World War Two; a war with substantial demographic consequences which have not yet fully played out.
The Scandinavian countries in particular had diverse experiences in that war. Sweden was neutral, Norway and Denmark were occupied, while Finland was successively friend and foe to the allied powers. So the change in the number of older people may differ in Sweden compared to the others. Nevertheless, Sweden still compares well with the other neutral countries: Switzerland, Ireland, Spain and Portugal. (Though noting that Spain had its own especially large demographic trauma in 1936 to 1939.)
Another problem in unravelling the demographics of Europe is the substantial international migration between present and former European Union countries, and immigration from former (or present) empire countries. So many people these days die in different countries from which they were born. We know little about the different pandemic and post-pandemic death experiences of immigrants compared to people born in the country of their death.
In most countries deaths in 2022/23 would have been higher compared to 2018/19. The main determinant of death rates is the numbers of people in the oldest age cohorts. About half of all deaths in most countries are of people in their eighties. So the biggest increases, for reasons other than the pandemic, would be due to the rate of increase or decrease of a country’s population of octogenarians. Some countries will have significantly fewer octogenarians after the pandemic, because the pandemic itself took so many.
The second most important reason for changing death tallies is the underlying health of the people. Pandemics take more people in countries which already have substantial populations – especially populations in the 65 to 74 age group – with compromised pre-pandemic health or compromised general immunity. In pandemic years, the main reason for more death is worse underlying health. In other years changes in health status may either accentuate or offset changes in the numbers of people over eighty. While there are health-compromised people of all ages, compromised health – high morbidity or low general immunity – is more likely to have prematurely fatal consequences for people aged 65 to 74.
To summarise the two previous paragraphs, I would argue that the two main predictors of a country’s normal death tally are the numbers of octogenarians in the population, and the numbers of people in the population aged 65 to 74 with compromised health or general immunity. (In addition, some developing countries still have unacceptably high levels of infant mortality.)
The two key aspects of the health status of living populations are morbidity and immunity. The countries which fare best in a novel virus pandemic (or from wave pandemics of pathogens which induce only-short-lived specific immunity) are those with low morbidity and high general immunity. With respect to the present post-pandemic period, the covid coronavirus increased both the morbidity and the immunity of populations. Where these two increases balance out, then a new normal appears which looks substantially like the old normal.
Before the twentieth century, people living rurally were more likely to experience longevity. That changed in the twentieth century, when people living in metropolises gained super-high-immunity levels from living in close proximity to each other (improving immunity); and urbanised populations experienced reduced morbidity as a result of access to a wider range of foods, from more timely access to healthcare services, less exposure to conditions such as malaria, and safer supplies of drinking water.
Big cities still reduce life outcomes for people immigrating from rural areas; for people not yet adapted to city levels of exposure to pathogens, and often having to settle for inferior housing and employment experiences. When governments tamper with the finely-tuned immunity equilibria in our big cities, the potential for deadly unintended consequences has always been there. Such tampering may include the required overuse of facemasks, and the creation of fear around the use of public transport.
The post-pandemic experience of East Asia is not a particularly good advertisement for disruptive public health practices. Sweden was conspicuous by taking the opposite policy tack from that taken in East Asia, minimising disruptions from normal social interaction. Sweden’s different approach was not a result of its greater wisdom or greater laisse-faire liberality; rather it was a result of a mistaken assumption that, by mid-March 2020, many more people had already been infected by the new coronavirus (making it too late for restrictive policies) than actually had been infected.
The interregnum between the two recent respiratory pandemics
Finally, it is worthwhile to suggest reasons why deaths in much of the developed world were especially low from May 2018 to February 2020; a phenomenon particularly marked in Sweden. This was most likely because of the 2017 influenza pandemic – the invisible pandemic (invisible even to demographers, then more attentive to issues other than heightened seasonal mortality). This world disease event left populations more immune, and (because that pandemic took so many) it meant that the post-influenza 2018 population was more healthy and had more immunity than the pre-pandemic 2016 population.
It is normal for post-pandemic death rates to be low for a couple of years. Indeed, it was true around 1919 and 1920, after the great influenza pandemic of 1918. Will it prove to be so this time, from 2023 to say 2025? We should be watching aggregate mortality – in our own countries and other countries – with as great interest as we watch the inflation, unemployment and economic growth data.
Keith Rankin (keith at rankin dot nz), trained as an economic historian, is a retired lecturer in Economics and Statistics. He lives in Auckland, New Zealand.