More than 6 million people have died from COVID-19 worldwide, according to official counts. But the more comprehensive toll, tallying deaths directly or indirectly attributable to COVID-19, may be three times higher, according to a new study published in the Lancet.
“We can confidently say that the pandemic has killed an extra 18.2 million people,” says Dr. Chris Murray, director of the Institute for Health Metrics at the University of Washington and a co-author of the paper.
Those 18.2 million people represent what epidemiologists refer to as “excess deaths,” or the additional number of people who have died in a given period—in this case, Jan. 1, 2020 to Dec. 31, 2021—compared to the number that would be expected to die in the same span of time in the past. The new study relied on data from 74 countries that tracked excess deaths and used computer models to extrapolate those figures out to 191 countries worldwide.
To understand approximately how many excess deaths COVID-19 caused, the researchers compared reported deaths in the 74 countries in 2020 and 2021 to 11 years of previous data. On average, 80% of the 18.2 million deaths beyond the expected amount were listed on death certificates as being caused by COVID-19. The other 20% were from multiple causes, such as chronic conditions like diabetes, obesity, and cardiovascular disease, but the researchers determined these to also be related to COVID-19. Blaming a heart attack, say, on COVID-19 may seem like a leap, but researchers determined that there was no other reason for cardiovascular and other deaths to have risen in 2020 and 2021 except for overburdened hospitals, fears of contracting the virus that prevented people from making regular visits to physicians to care for their chronic conditions, and other pandemic-related obstacles to health care. Excess deaths among seniors, a population especially vulnerable to the worst effects of the virus, were more likely to have been caused by COVID-19 than those among other age groups.
“There was an increase in coded deaths for dementia,” Murray says. “But it’s very likely that these could be people in nursing homes or elder care who died and never got tested [for COVID-19].”
Geography made a huge difference in which populations were at greatest risk of dying from COVID-19. A handful of places—including Iceland, Australia, Singapore, New Zealand, and Taiwan—actually experienced a reduction in overall deaths in the studied two-year period compared to similar periods in the past. This was likely due to effective lockdown protocols that led to lower rates of COVID-19 and other infectious diseases like influenza, the researchers say. These pandemic measures also likely reduced rates of deaths due to injuries that may have occurred outside of the safer confines of the home.
But the numbers were far grimmer elsewhere. The world’s hardest hit regions were South Asia, North Africa, the Middle East, and Eastern Europe. By country, the greatest number of excess deaths occurred in India, with 4.07 million lives claimed; the U.S., at 1.13 million; Russia, at 1.07 million; Mexico, at 798,000, and Brazil at 792,000.
Part of the reason those countries rank first is simply because of their high populations. A more accurate measure of the toll of the pandemic country by country is numbers of excess deaths per 100,000 people. Measured that way, the five hardest hit countries or regions were Bolivia, at 735 excess deaths per 100,000 people; Bulgaria, at 647; Eswatini, in southern Africa, at 635; North Macedonia, with 584; and Lesotho, at 563.
The authors of the paper were careful to eliminate confounding factors that had nothing to do with COVID-19. For example, the model they built excluded deaths potentially related to natural disasters like heat waves—such as one that struck in Europe in July and August of 2020. By contrast, they included data that showed an increase in opioid deaths in some parts of the U.S., which is linked to pandemic isolation and a drop in access to addiction treatments. And they took special note of excess deaths officially recorded as being a result of diabetes or obesity.
“We know that diabetes and obesity are the biggest risk factors, other than age, for dying from COVID,” says Murray. “So we’re pretty suspicious that those are just miscoded COVID deaths.”
Vaccination efforts were hampered too, especially among children in the developing world, which may have led to a rise in vaccine-preventable diseases. Around the world, the emotional and psychological impacts of pandemic fears and isolation may have taken its own excess-death toll through a rise in depression and other psychiatric conditions. “There is convincing evidence that rates of anxiety and depression increased during the pandemic period,” the authors of the paper wrote, “which might lead to increases in deaths from suicide.”
The study is not without its shortcomings, not least being that the 74 countries from which reliable mortality and official cause-of-death reports were available represent just 38% of the 191 nations included in the paper overall. No computer model is perfect, and attributing every one of the 18.2 million excess deaths in 2020 and 2021 to the pandemic might be an overreach. “Direct measurement would be preferable to modeled excess mortality,” the authors conceded.
Still, 18 million additional deaths occurring during a pandemic are hard to explain any other way. COVID-19 may not have claimed all of those lost lives, but it surely took a huge share. “We don’t have hard and fast evidence on it,” says Murray. “But we are saying that the majority of these 18.2 million people would not have died but for the pandemic.”