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Do we have the right balance?

Aggregate population health and COVID-19

The world has been shaken by unprecedented efforts in the name of public health. But, efforts to arrest COVID-19 were not initially formulated with a comprehensive view of the public health in mind. These policies must be adjusted and revisited if they are to promote public health holistically conceived.

The most widely accepted answer to the question, “What is the public health?”, is given by measures of aggregate population health which attempt to describe the overall health experience of a population by summing the experiences of its members. These quantify the costs of death and disability in terms of lost healthy life years.

For example, a disease that causes children to die results in a loss of healthy life years, diminishing aggregate population health. Indeed, such a disease causes a bigger loss to healthy life years than one that affects an equal number of adults. This is a feature common to the two measures which are most prominently used: Quality Adjusted Life Years (QALYs) and Disability Adjusted Life Years (DALYs).  

Such measures of aggregate population health have been heavily promoted and adopted in global health policy by international organizations – notably the World Health Organization, private foundations (most prominently the Bill and Melinda Gates Foundation), bilateral aid agencies, and governments. These measures have critics, including myself, but there is no doubting their influence. As a result, it is reasonable to ask what they might tell us about the response to COVID-19.

Efforts to address one disease may benefit or harm efforts to address another

The International Monetary Fund (IMF) predicts a 4.9% reduction in world GDP this year as a direct result of lockdowns, or more than US$4 trillion at market exchange rates. If a world growth rate of 2% is assumed as the counterfactual for 2020 (the world growth rate was 3.1% in 2018), then the costs exceed US$5 trillion, more than the total worldwide public expenditure on health prior to the crisis of US$4.7 trillion.

It is likely that efforts to prevent COVID-19 related health losses have already cost more per healthy life-year saved than what is expended to prevent losses to other causes of death, even in the rich countries where such expenditures are typically high.

The massive expenditures of resources to avoid loss of life years from most diseases, including COVID-19, in developed countries greatly exceeds the resources necessary to avoid comparable loss of life years in developing countries ...

Efforts to address different threats to ill health should be balanced across diseases, as aggregate population health is affected by the cumulative losses of health due to death or disease from all sources. We must therefore ask whether the knock-on consequences of measures to address one disease impact the ability to address other diseases. These effects might be either positive or negative. For instance, social distancing may reduce the spread of other infectious diseases too, while lockdowns may make it more difficult to administer immunizations.

There is already ample evidence of sizable adverse health consequences from lockdowns, including the failure to scan patients for cancer, to immunize children for preventable illnesses, to undertake anti-malarial activities,  or to treat tuberculosis and other diseases. The knock-on effects on other health outcomes of policies to address COVID-19 do not appear to have been adequately anticipated by policy makers.  

 
Proportionality is the key to a balanced response

Despite uncertainties, a balanced approach to protecting population health requires that the relative attention given to different threats should consider whether efforts are distributed sensibly between (1) different diseases, (2) different places, and (3) different points in time.

For example, in most approaches to the public health the importance given to an illness that affects a certain group should reflect the share of that group within the population. It is well-established that the elderly face disproportionate mortality risks from COVID-19. The appropriate balance between efforts to address COVID-19 and those that affect the health of the young and the middle-aged – such as malaria or tuberculosis – should then depend on the relative share of the elderly in the population.

In Africa, the share of the population over 65 is around 3% compared to 17% in Europe. The optimal balance between efforts to attack different diseases should vary across world regions for this reason alone.

Resources applied to address health concerns in one place can also potentially be employed elsewhere. The massive expenditures of resources to avoid loss of life years from most diseases, including COVID-19, in developed countries greatly exceeds the resources necessary to avoid comparable loss of life years in developing countries, both because easily preventable deaths are more frequent and because the cost of health interventions is lower. If life years were valued equally everywhere, as they should be, then the disproportionate expenditure of resources across countries would not be as great as it is, and the effect of actions taken in one country on outcomes elsewhere would be more frequently considered.

All of this is not to deter actions against COVID-19, but rather to emphasize that it is essential to consider their full health consequences.

Proportionality over time is another consideration because resources deployed now might determine what is possible subsequently. In the case of the policy response to COVID-19, the contraction of the world economy and the associated build-up of debts comes at a potential cost to future social expenditure on other health and non-health goals.

All of this is not to deter actions against COVID-19, but rather to emphasize that it is essential to consider their full health consequences. A sizeable expenditure of resources would be wholly justified to arrive at a vaccine or other interventions that make it possible to suppress the disease permanently in the future. But day-to-day efforts to diminish deaths from the disease must, in the aggregate population health perspective, be subject to the very same criterion that is applied when determining how much to expend on other threats to health.

Both those who apply aggregate population health perspectives and those who favour alternatives must recognize the need for balance. The need to take note of the comprehensive health consequences of interventions comes not from a tradeoff between health and non-health concerns, but from attention to health itself.

The views expressed in this piece are those of the author(s), and do not necessarily reflect the views of the Institute or the United Nations University, nor the programme/project donors.