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New estimates from the World Health Organization (WHO) suggest that, between 01/01/2020 and 31/12/2021, the full death toll associated directly or indirectly with the COVID-19 pandemic (described as ‘excess mortality’) was approximately 14.9 million.
Prof Amitava Banerjee, Professor of Clinical Data Science and Honorary Consultant Cardiologist, Institute of Health Informatics, UCL, said:
“These robust analyses from WHO highlight four neglected aspects of the pandemic. First, the impact of the pandemic is far greater than direct COVID-19 deaths alone; there are far-reaching effects on health systems and society which have resulted in many more excess deaths. Excess deaths have been used as a metric throughout the pandemic to predict and to evaluate the impact of COVID-19 on all-cause mortality (“deaths from any cause”) compared with the pre-pandemic period, which includes both the direct effects of COVID-19 and the indirect effects on non-COVID deaths1. This is in contrast to COVID-19 deaths which have been commonly used and are based on having accurate estimation of SARS-CoV-2 infection and on accurate registration of cause of death due to COVID-19. Both infection rates and COVID-19 as a cause of death are likely to have been under-estimated across countries.
“Second, broadly speaking, the impact has been greatest in countries which have not prioritised infection suppression policies and have had high infection rates throughout the pandemic. This explains why the UK with less than 1% of the world’s population, is in the list of ten countries worst affected by the pandemic. Some countries which may have had looser lockdown measures, such as Sweden, had fewer excess deaths than the UK. One explanation could be the overall smaller population (because it means that the population is more spread out, and that a much higher percentage of the population would need to be affected to be in the “top 10 countries” for number of COVID deaths), lower “case load”, less COVID-19 death rate and less impact on overall health services leading to less indirect effects of the pandemic.
“Third, the pandemic has shown that too often, the places where the need for robust data is greatest, the data is suboptimal or unreliable, such as in India. As the authors note: “This lack of capacity and the data required to monitor ACM has been exacerbated during the unprecedented pandemic.” These analyses highlight the crucial role for ongoing surveillance in pandemic response and pandemic preparedness, which must be prioritised urgently. No country can afford to be complacent.
“Fourth, we cannot know what we do not measure, and we cannot act on what we do not know. Because excess deaths have not been counted rigorously across countries, the indirect effects on non-COVID deaths have not been fully appreciated and health systems have been ill-prepared. The recent WHO analyses only concern mortality and do not include morbidity. To-date, the long-term effects of COVID-19 (“Long Covid”) are absent from global estimates of COVID-19 impact. Therefore, international action against this further, debilitating consequence of the pandemic is largely lacking.”
1 Banerjee et al. Lancet 2020. https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(20)30854-0/fulltext
Prof Kevin McConway, Emeritus Professor of Applied Statistics, The Open University, said:
“It’s not at all surprising that this latest estimate of excess deaths from WHO is well in excess of the total of official Covid deaths from all the countries. That’s for several reasons. One is that different countries have different ways of defining what’s meant by a Covid death, and some of the definitions are quite restrictive. Often deaths where the person did not test positive for the virus would not be included, but at times and in places where testing was limited, that would rule out possibly rather a lot of deaths that really did involve Covid. Another reason is that, in many countries of the world, in some cases because they are poorer and don’t have good systems for counting any deaths, not all deaths that would reasonably be regarded as being caused by Covid are recorded at all.
“But one main reason is that official Covid death counts generally include only people whose death was directly caused by the virus. But other deaths will have been caused less directly by the pandemic, for instance because of reduced access to health care. So many statisticians (including me) consider it’s important to look at excess deaths – the difference between the number of deaths from all causes that actually occurred during the pandemic, and the numbers that would have been expected to occur over the same time period if there had been no pandemic. I’m not saying that’s the only number one should look at, but it’s important.
“To get a figure for excess deaths, you need two numbers – the number of deaths that actually did occur, and an estimate of the number that would have occurred if the pandemic hadn’t happened. Then you just subtract the expected number from the actual number, and that give the excess deaths. But it’s not so easy in practice. Both of the numbers involved have to be measured or estimated, and both are subject to errors and difficulties. In a richer country like the UK, the number of deaths that actually happened is known fairly precisely, because there is complete death registration (though there can be delays in the system). It can get trickier to give the causes of the deaths, but that’s not relevant here, because for excess deaths we look at deaths from all causes, so it’s not necessary to assign a cause. But in poorer countries there may not be anything like an adequate system of death registration, or there may be major delays in getting the numbers, so in calculation these excess deaths figures, WHO had to estimate the actual numbers of deaths for several countries.
“Getting the expected number of deaths that would have occurred if there had been no pandemic is more obviously a problem – this is a counterfactual situation that did not occur, so an estimate has to be produced using a statistical model (that might be simple or complicated). There are different ways to produce that estimate. WHO have their method. Another is used by the Economist newspaper1, and there are more produced by different organisations. They don’t give the same results as one another. WHO says that the global total for the years 2020 and 2021 is 14.9 million excess deaths. For the same period, the Economist got an even larger number, about 18 million, and their current estimate from the start of the pandemic to now is 21.3 million – though they make it clear that there is considerable uncertainty about that figure, and that a margin of error for it runs from 14.7 million to 25 million. WHO also give error bounds for their excess deaths estimate for 2020-21. They run from 13.3 million to 16.6 million, so narrower bounds that the Economist provide – and my feeling is that, given all the sources of uncertainties involved, the Economist is being more realistic about the overall uncertainty. But there’s no doubt that the global excess deaths figure is very, very much greater than the recorded numbers of death actually officially allocated to Covid as a direct cause.
“The WHO report includes a list of 20 countries, which, they say, represent “approximately 50% of the global population, [and] account for over 80% of the estimated global excess mortality for the January 2020 to December 2021 period.” The UK is on that list. (In full, it is Brazil, Colombia, Egypt, Germany, India, Indonesia, Iran, Italy, Mexico, Nigeria, Pakistan, Peru, the Philippines, Poland, the Russian Federation, South Africa, the United Kingdom, Turkey, Ukraine, and the United States of America.) They are not clear on how they chose this particular list, but I think I have figured it out. They estimated the excess deaths total, for the two years in question, for every country in the world, and these 20 countries are the first 20 on the list, when it’s ranked in order of total excess deaths. The actual estimates for those 20 countries range from 4.7 million for India, with Russia second at 1.1 million and Indonesia third at 1.0 million, down to Poland, 19th at 157,000 and the UK twentieth, 148,000. So while it’s not wonderful to see the UK on such a list at all, at least it is not near the top.
“Another feature, though, is that all the countries on the list have large, or at least largeish, populations. Other things being equal, which of course they aren’t, you’d expect a country with a bigger population to have more excess deaths, simply because it has more deaths overall because of its large population. As it happens, the WHO also provide a figure for the number of excess deaths in relation to the total population of the country, and one can rank the world’s countries in terms of that. I think that measure is considerably more appropriate, if one really wants to rank countries.
“On that basis, the top 20 countries with the most excess deaths per 100,000 population are, in order from the highest downwards, Peru, Bulgaria, Bolivia, North Macedonia, Russian Federation, Armenia, Serbia, Lithuania, Montenegro, Georgia, Azerbaijan, Romania, Belarus, San Marino, Mexico, Andorra, Bosnia and Herzegovina, Ecuador, Ukraine, Moldova. Most are in Eastern Europe, a few in Latin America, and I’m not certain that the estimates for the tiny countries (Andorra and San Marino) are going to be very accurate. Peru, top of the list, had an estimated 437 excess deaths per 100,000 population, and Moldova (20th) had 225 per 100,000. The UK comes in much lower, at number 56 on the list in this order, with 109 excess deaths per 100,000 population. We could certainly have done better, but the UK comes about a quarter of the way down the list (which includes 194 countries in all).”
1 See https://www.economist.com/graphic-detail/coronavirus-excess-deaths-tracker, and the Economist’s figures are also reported by Our World in Data at https://ourworldindata.org/excess-mortality-covid#estimated-excess-mortality-from-the-economist
Prof Matt Sydes, Professor of Clinical Trials & Methodology, UCL, said:
“The many problems with understanding what was meant by “deaths from Covid-19”, when people previously tried to report such data, have included: not every person who died from Covid-19 would have been formally diagnosed beforehand; there has been disagreement over time, geography and speciality on what was meant by death from Covid-19 (death after diagnosis or death suspected to be from Covid? And ever or within a fixed point); and some people will have died because of issues arising other issues around the Covid-19 era (e.g. difficulty accessing healthcare services for other diseases).
“Excess mortality was always going to be the better (only?) way to look at the impact from Covid-19 on survival. Excess mortality is the increase in the number of deaths compared to what would have been expected.
“When it comes to comparisons between countries, the UK has high-quality national coverage of mortality information and is well-placed to contribute to these comparisons, regardless of the message about the country’s findings. With the exception of China, the countries listed in the section that includes “Twenty countries, representing approximately 50% of the global population, account for over 80% of the estimated global excess mortality for the January 2020 to December 2021 period” in the summary on excess deaths, are also those that feature highly in terms of the largest populations, so it is perhaps there are no surprises in the countries named.
“This work from WHO clearly sets out estimates globally of the impact on survival of the Covid-19 era. It’s huge – way bigger than previously estimated. The modellers at WHO have worked hard to make good estimates where national level data on deaths is not available.
“15 million deaths. How many of these could have avoided through better choices by individuals, healthcare systems and governments? Death is a key outcome from Covid-19, or was in the early days of the pandemic. Research has shown how many people can be treated well. Most people who get Covid-19 do not die from the disease. But many will be impact in other ways, potentially for a very long period if they have Long-Covid. This work cannot comment on that wider burden from the disease, and it’s unlikely that reliably information on this burden be achieved.”
Prof Sir David Spiegelhalter, Chair, Winton Centre for Risk and Evidence Communication, University of Cambridge, said:
“Caution is needed when using these estimates to compare countries, due to the considerable uncertainty even about countries with good data. For example, the excess death rate for the UK over 2020-21 is estimated to be 109 per 100,000 and for Germany it is 116 per 100,000, apparently greater than the UK. But the UK estimate has a range from 98 to 121, while Germany has a range of 96 to 137, completely including the UK range. Therefore these WHO figures cannot be used to claim there is any difference between UK and Germany.”
Prof Thomas House, Professor of Mathematical Statistics, University of Manchester, said:
“Regarding the section titled ‘Observing trends in regions and income groups’1 which gives the twenty countries that account for over 80% of the estimated global excess mortality for the January 2020 to December 2021 period, a quick back of the envelope calculation on this: China is about 20% of the world’s population and has had very few deaths due to its unique zero-COVID policy. This on its own makes the figures quoted much less surprising, so in response to the questions that have been raised about the significance of a country’s presence on the list, it seems that there is relatively little that can be inferred.”
Prof John Edmunds, Professor in the Centre for the Mathematical Modelling of Infectious Diseases, London School of Hygiene & Tropical Medicine, said:
“We know that not all deaths due to COVID are recorded – people may die without being tested and so would never appear in the official COVID death statistics. In addition, the pandemic may lead to changes in the number of deaths from other conditions, e.g. if patients with other illnesses (such as heart disease) are not able to receive care because the hospitals are filled with COVID patients. “Excess deaths” is a measure that gives a more complete picture of the impact of the pandemic on overall deaths. It is simply the difference between the number of deaths that you might expect to see in a given time period (e.g. a week or a month) and how many were actually observed.
“Sadly, the figure of around 15 million deaths globally over the first 2 years of the pandemic is likely to be much more accurate than the 6 million or so confirmed deaths that have been recorded. Having said that, there are difficulties in calculating excess deaths, particularly in many low-income countries. In high income countries we register every birth and death (in England this has been done since 1832) so we know very accurately how many deaths we would expect to see on a given week (we can take the average from the previous few years) and compare it to how many actually occurred. However, in many low income countries, including almost all sub-Saharan African countries, births and deaths are not routinely registered. Hence WHO had to use a model to estimate how many deaths might have occurred anyway and what the excess might have been – the model using data from other countries that do have good statistics. This is obviously problematic when you have large groups of countries with little or no relevant data, as we have in Africa. For this reason, other researchers using other models have come up with different estimates. A recent paper in the Lancet, for instance, (https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(21)02796-3/fulltext) estimated that there have been about 18 million excess deaths globally. Although these estimates are different, the overall pattern from these two studies is similar: the true burden is likely to be much higher than the confirmed deaths figures and middle income countries have tended to fare the worst over the epidemic.”
Dr Jeremy Farrar, Director of Wellcome, said:
“There can be no hiding from the fact this devastating death toll was not inevitable; or that there have been too many times in the past two years when world leaders have failed to act at the level needed to save lives. Even now a third of the world’s population remains unvaccinated.
“More must be done to protect people from the ongoing Covid-19 pandemic and shield humanity against future risks. Climate change, shifting patterns of animal and human interaction, urbanisation and increasing travel and trade are creating more opportunities for new and dangerous infectious disease risks to emerge, amplify and then spread.
“Governments must learn from this crisis and act immediately to end this pandemic, and make sure they do everything they can to prevent this ever happening again. This means building and sustaining national and global surveillance networks to detect outbreaks before they escalate, supporting national and global networks of public health professions who can swiftly respond when an epidemic starts, and vastly expanding and equitably distributing R&D and manufacturing capacity for vaccines, treatments and diagnostics. To work, these all must be built-in to local health systems and operational every day, not just in times of crisis.”
All our previous output on this subject can be seen at this weblink:
www.sciencemediacentre.org/tag/covid-19
Declared interests
Prof Amitava Banerjee has no conflicts of interest. He is PI of the NIHR-funded STIMULATE-ICP study in individuals with Long Covid. He has received research funding from NIHR, UKRI, EU, Astra Zeneca and British Medical Assocation.
Prof Kevin McConway: “I am a Trustee of the SMC and a member of its Advisory Committee. I am also a member of the Public Data Advisory Group, which provides expert advice to the Cabinet Office on aspects of public understanding of data during the pandemic. My quote above is in my capacity as an independent professional statistician.”
For all other experts, no reply to our request for declarations of interest was received.