Early in the COVID-19 pandemic, the risk of dying from the disease was roughly twice as high for people living in lower-income countries as for those in rich nations, a study reports.
The research, published in BMJ Global Health in May1, is one of a growing number of studies to reveal COVID-19’s massive burden in lower-income countries.
Data from early in the pandemic suggested that death and infection rates in poor countries were relatively low compared with those in rich ones. But recent evidence paints a very different picture, says Madhukar Pai, an infectious- disease epidemiologist at McGill University in Montreal, Canada. “This paper is one among many that illustrate that the biggest impact of this pandemic has been on low- and middle-income countries,” says Pai.
To assess the burden of COVID-19, Gideon Meyerowitz-Katz, an epidemiologist at the University of Wollongong in Australia, and his colleagues analysed infection and mortality data gathered from dozens of studies in 25 low- and middle-income countries before vaccines against the coronavirus were rolled out in those regions. Between April 2020 and February 2021, researchers collected blood samples from people in various age groups and looked for antibodies against SARS-CoV-2 — a sign that someone had previously been infected.
In rich countries, older individuals — who are most vulnerable to the disease — were less likely to have been infected than young people. But the authors found that in most lower-income countries, the percentage of adults aged 60 and older who had antibodies against the coronavirus was similar to that of young people. This is probably because many people in these countries live in multigenerational households, which makes isolating from an infected person difficult, says Meyerowitz-Katz. And many people in these places did not have the opportunity to work from home, he says.
To calculate a person’s risk of dying, the team calculated countries’ infection fatality rates, the portion of infected people who die from the disease, including those who didn’t get tested or show symptoms. The average infection fatality rate of 20-year-olds in low-income countries was nearly three times that in rich nations, and 60-year-olds had almost double the risk of dying compared with that in wealthy countries (see ‘How deadly is COVID-19’). The stark difference in risk was probably because people in low-income countries had less access to good-quality health care, says Meyerowitz-Katz.
Study co-author Ana Carolina Peçanha Antonio, an intensive-care physician at the Hospital de Clínicas in Porto Alegre, Brazil, experienced this first hand. In a temporary intensive-care unit that she managed, there were no staff members who were specialized in treating COVID-19, so Peçanha Antonio and her colleagues had to make “huge efforts” to keep patients safe and well cared for — an “overwhelming scenario”, she says.
As COVID-19 vaccines have become available, the mortality gap between low- and high-income countries might have shrunk, Meyerowitz-Katz says. But it could also have widened, because many poorer nations still have limited access to vaccines. “It’s hard to know precisely how that’s changed over time,” he says. When vaccines were approved, wealthy nations hoarded them, which exacerbated the vaccine equity gap between rich and poor countries, says Pai.
More help needed
The main findings aren’t surprising, says study co-author Daniel Herrera-Esposito, a neurobiologist at the University of the Republic in Montevideo, Uruguay. But they highlight how high-income nations failed to assist lower-income countries properly during the pandemic, he says. “It’s depressing.”
The results also underscore “the urgency of vaccinating people in low- and middle-income countries”, says Gavin Yamey, who studies global-health and public policy at Duke University in Durham, North Carolina. Only 16% of people in low-income countries have received at least one dose of a COVID-19 vaccine, compared with 80% of individuals in rich nations.
Donations of vaccines timed for when lower-income nations can use them could help to achieve a sustainable and fair global vaccine distribution, Yamey says. Support for those countries to produce doses locally would also help.
But Pai worries that it might be too late for poorer countries to get enough doses to vaccinate most of their populations, because rich nations have started to move on and cut funding for COVID-19-related international aid programmes. He notes that similar patterns have played out with other infectious diseases, such as malaria, tuberculosis and AIDS, which were once serious threats in rich countries. “The minute these diseases stopped being a threat, we totally forgot about them, we pretended they were over. And where are they now? Killing people in the global south,” he says. “In pretty much every major infectious disease you can think of, it’s the low- and middle-income countries that bear the brunt of it.”