Young and old: The mortality trade-off of COVID-19 lockdowns in developing countries

The COVID-19 virus and subsequent series of lockdowns had a major effect on mortality among the young and old of different countries. Whilst this may be a sensitive topic for some listeners, it is important to understand lockdowns in the case of future epidemics.

Professor Lin Ma and colleagues at the World Bank and University of Michigan investigate the impact of economic downturns following national lockdown protocols, and their link to deaths in respective countries. The researchers reveal an intergenerational mortality trade-off surrounding lockdown policy in lower- and middle-income countries. Indeed, this raises difficult ethical questions for how governments should respond to pandemics in the context of global economic inequality.

Read the original research: https://www.nber.org/papers/w28925

Transcript:

Hello and welcome to ResearchPod. Thanks for listening and joining us today.

In this episode we’re talking about lockdowns in response to the COVID-19 virus, and the effects these had on mortality among the young and old of different countries. Understandably, this may be a sensitive topic for some listeners. As will be mentioned throughout this episode – the study we are examining today is a statistical investigation, not political commentary, not a critique of healthcare systems, and certainly not evidence of conspiracy or misinformation. The findings aim to inform and improve the implementation of social interventions such as lockdowns in the case of future epidemics.

We will be drawing from a study by Lin Ma, Assistant Professor of Economics, and colleagues at the World Bank and University of Michigan. Their study investigates impact of economic downturns following national lockdown protocols, and their link to deaths in respective countries. More specifically, the study finds that - in developing countries - lockdowns are associated with a net increase in child mortality. In other words, for every individual that lockdowns saved from COVID-related deaths in the lowest ranking economies, more children lives are lost from their economic consequences. Therefore, researchers reveal an intergenerational mortality trade-off surrounding lockdown policy in lower- and middle-income countries. Indeed, this raises difficult ethical questions for how governments should respond to pandemics in the context of global economic inequality.

Since the outbreak of the COVID-19 pandemic, governments have used lockdown policies to contain the spread of the virus. To varying degrees, lockdowns have involved restricting the movement of people and mandating the closure of public and commercial services. This aims to minimise interactions that lead to viral infection, thereby protecting population health and reducing deaths. The economic disruptions caused by lockdowns have sparked fierce debate over whether they are truly justified. Much of this debate has centred around the trade-off between the lives saved versus the economic costs of the policy. However, this calculation assumes that lockdowns bring only financial repercussions, and are not also implicated in mortality rates. These assumptions have recently been brought into question, due to concerns that in developing countries both the disease and lockdown policies can increase mortality – for older and younger individuals respectively.

Soon after the pandemic hit, evidence emerged showing that older age groups are at increased risk of death from COVID-19. However, pre-existing evidence indicates that when low- and middle-income countries encounter an economic downturn, infant and child mortality rises. This suggests that lockdowns could increase deaths among the young, just as the economic slumps related to other causes have this same outcome. A recent article by Professor Lin Ma and co-authors seeks to quantify this trade-off behind the choice of whether or not to lockdown.

The researchers examined data from 85 countries, representing each category of national income. Mortality rates were then measured for children, working adults, and the elderly. Data from a 7-week period were used to capture lockdown outcomes from relevant countries, to compare with figures for countries without restrictions in place.

Specific country factors were analysed to find the key drivers for international variations in mortality rates. One such factor incorporated into the study was changes in GDP. This measure captures the intensity of the economic recession resulting from a lockdown, and thus reflects the degree to which jobs are lost and consumption is inhibited by cuts to incomes and the labour supply. Another factor was country demography. Since poorer countries are generally younger than their richer counterparts, and younger populations are more vulnerable to recession-related deaths, demographics might help to explain international differences in mortality rates. Still another variable was the proportion of social contact occurring in work or the community. Since interactions in poorer countries are more often community-based, this could reduce the ability of lockdowns to save lives in those countries. These are some among a range of factors explored in the research.

The study found that, in low-income countries, lockdowns led to an average of 1.76 child deaths for every COVID-19 fatality averted. The net increase in mortality from lockdowns disappeared for countries of lower-middle income and above. However, child mortality remained a cost of lockdowns for those countries in the middle, with a ratio of 60 child fatalities to every 100 viral deaths averted in lower-middle income countries, and 6 to 100 in upper-middle.

High income countries did not encounter a mortality trade-off, with no child mortality associated with the economic repercussions of lockdown. The richest countries managed to decrease total deaths by 6.2% through their lockdown restrictions. This compares with the poorest countries, where lockdowns were associated with a 2.6% increase in total mortality. Researchers also studied the aforementioned country characteristics to establish which variables were the key drivers of national mortality rates. The study found that demography - specifically the higher ratio of children to the elderly in poorer countries - as well as GDP changes were the core drivers of international difference.

Based on these findings, the researchers advocate for a utilitarian approach to designing lockdown policies. In such an approach, variables including intensity of the expected economic recession and age demographics are taken into account by social planners when considering the mortality trade-off of lockdowns. This may involve a determination that softer restrictions are better for low-income countries, where total deaths and their concentration among children are harsher under a lockdown compared to a non-lockdown scenario. Indeed, the optimal lockdown will vary across countries, as the costs and benefits to each policy choice will be influenced by distinct national characteristics.

The study finds that milder lockdowns in poorer countries would reduce child deaths to 0.32 for every COVID-19 fatality averted. This example demonstrates that a utilitarian approach, following the key findings of the study, offers a promising method for social planners to incorporate a wide array of risk into their policy calculations during a pandemic. However, looking to the future, another variable enters into the equation.

Whilst COVID-19 fatalities have been skewed towards older age groups, other viruses may differ. As an example, the 1918–1919 influenza pandemic was characterised by a predominance of excess death among young adults. Since the future of viral outbreak is yet to be written, social planners must be prepared to incorporate new risks into their ethical calculus, allowing them to make informed choices that maximise survival against the particular threat and society in question. This research takes us one step further to that readiness.

As Professor Lin Ma states: “nonpharmaceutical interventions to prevent infectious disease spread will likely affect subgroups of the population in an adverse manner and will do so in a context-specific way”. However, Ma maintains that targeted policies, such as income transfers to poor households, can alleviate these adverse effects, even while lockdowns are enforced. “Indeed, epidemic containment policies have a positive impact on the rest of the world by reducing the likelihood that novel and possibly more lethal variants will emerge. As such, a case can be made that wealthier countries would benefit from, and carry a moral responsibility to, finance these mitigating instruments for low-income countries, such as through development assistance programs”.

Once again, we emphasise that this study is making a statistical conclusion, and should not be taken as support or condemnation of any political group, national practice or other COVID-19 response. The lives lost over the course of the pandemic, and the millions of those affected by it, are not to be diminished in any way. 

That’s all for this episode – thanks for listening, and be sure to click through to Prof Lin Ma’s original article in the show notes for this episode for more of the details from this study. And, as ever, stay subscribed to ResearchPod for more of the latest science.

See you again soon.

Also published on https://researchpod.org/health-medicine/mortality-trade-off-covid-19-lockdowns-developing-countries

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