Ideally, we’d also take account of the average level of contact among individuals. In densely populated, highly social contexts—urban environments, with wet markets, shantytowns, or subways—that number is high; in rural environments, it tends to be low. The virus spreads more easily in crowded spaces.
The task, then, is to factor in both intrinsic vulnerabilities (such as age or obesity) and extrinsic vulnerabilities (the structures of households, the levels of interpersonal contact). And here you start to get a sense of the challenges that our medical mathematicians must contend with. There are trade-offs battling trade-offs: are the risks greater for a younger country with a larger family size but with infrequent social contacts or for an older country with a smaller family size but frequent contacts?
The epidemiologists with whom I spoke agreed that these variables were the important ones to factor in. Accordingly, amid the spring surge, researchers at Imperial College London enlisted these variables in building models of COVID-19 mortality—with options for dialling up or down the level of interpersonal contact and viral contagiousness, and generating a range of possible outcomes.
“Look, I don’t come into your home office and tell you to get out of the tub.”Cartoon by Alexander Andreades
The models didn’t always provide a time period when these deaths would occur; perhaps the worst is yet to come. Still, for rich countries, deaths predicted by the model weren’t far from what we’ve seen, or, anyway, what we can now reasonably extrapolate. (The pandemic is far from over.) The surprise emerged when looking at South Asia and most of sub-Saharan Africa. The model—which, it should be emphasized, took age differences into account—appeared to be off, in most cases, by a staggering margin. Pakistan, with a population of two hundred and twenty million, was predicted to have as many as six hundred and fifty thousand deaths; it has so far reported twelve thousand. Côte d’Ivoire was predicted to have as many as fifty-two thousand deaths; by mid-February, a year after the pandemic reached the continent, it had reported under two hundred.
I called Abiola Fasina, an emergency-medicine physician in Lagos, Nigeria. In the early days of the pandemic, a prominent sponsor of public-health initiatives in Africa had envisaged “bodies out on the street” there. Between April and July, Fasina had run a field hospital and an isolation unit for COVID-19 patients. At first, she told me, “we were seventy or ninety per cent full. When I walked through those wards, I remember that the patients were mostly asymptomatic or mildly symptomatic. But as the pandemic continued patients mostly remained mildly symptomatic. It’s all quite mild over here.”
I asked Fasina, who is also a health-policy expert, to look out her office window at the street life below. “You know, life goes on pretty normally,” she told me. “The markets are open. If you walk around the city, there are some people with masks and some without.” Watching a video of street life in Lagos, I had a similar impression. In December, 2020, as London entered another stringent lockdown, the storefronts on Lagos’s Nnamdi Azikiwe Street and Idumagbo Avenue were open. Carts shaded by brightly colored umbrellas were doing a brisk business. A woman carrying a basket on her head navigated gracefully past a man pushing a trolley full of gasoline cannisters.
A policeman pulled a motorist over—because he was unmasked? No, because he was smoking, and in Lagos State it’s against the law to smoke while driving. Meanwhile, dozens of maskless people pushed past one another through shoulder-to-shoulder pedestrian traffic.
“Lagos is many things, and it’s New York in Africa—activity on steroids,” Olajide Bello, a lawyer there, told me. “We practically all live cheek by jowl, with almost no green spaces.” The city, with fourteen million inhabitants, has returned to its usual chaos, Bello found. In late January, amid a new surge in COVID-19 infections, a national mask mandate was enacted, but enforcement has been spotty, and so has compliance.
Nigeria was predicted to have between two hundred thousand and four hundred and eighteen thousand COVID-19 deaths; the number reported in 2020 was under thirteen hundred. Ghana, with some thirty million residents, was predicted to see as many as seventy-five thousand deaths; the number reported in 2020 was a little more than three hundred. These numbers will grow as the pandemic continues. As was the case throughout much of sub-Saharan Africa, however, the statistical discrepancy was of two orders of magnitude: even amid the recent surge, the anticipated devastation still hasn’t quite arrived. The field hospital that Fasina had helped set up in Lagos was packed up and shut down.
Could the mortality gap be a mirage? Politicians may have an incentive to minimize the crisis (although the matter of incentives is complex: countries like Ghana and Nigeria sought and received billions of dollars in foreign assistance to help them combat the virus). At the same time, COVID-19 can be stigmatized in poorer countries, and, as Mobarak pointed out, that stigma, which he’s seen in Bangladesh, “can lead to exclusion from economic life.” The fishmonger has cause to keep his infection covert. And it’s easy to imagine how such deaths might be underreported; a coroner’s report might classify a COVID-19 death as “pneumonia” or “sepsis.”
Oliver Watson, an epidemiologist at Imperial College London, who helped build the models, had a strong argument that systemic underreporting was a factor. He cited the example of malaria: “Only one in four deaths from malaria are estimated to be detected globally—in some low-income settings, it can be one in twenty. And so a one-in-ten detection rate for COVID-19, an illness that carries far greater stigma, might well easily explain some of the discrepancy.” Most of these undetected COVID-19 deaths occur at home, and hospitals routinely record COVID-19 deaths incorrectly.
Watson directed me to a study in Zambia, which recorded under four hundred COVID-19 deaths in 2020. (The model had predicted between twenty thousand and thirty thousand there for the entirety of the pandemic.) In Zambia’s capital, Lusaka, researchers performed postmortem tests of three hundred and sixty-four people who had been assigned various causes of death, and found that the coronavirus was present in seventy, or almost one in five. Forty-four of the seventy had manifested symptoms suggestive of COVID-19, including cough, fever, and shortness of breath, though only five had been tested for the virus while alive. The researchers carefully distinguished between “probable” and “possible” COVID-19 deaths, drawing from often scant clinical records, but, whatever the exact numbers were, it was obvious that the official records drastically shortchanged the reality. Lawrence Mwananyanda, a physician and global-health expert who helped lead the study, believes that Zambia’s real death toll from COVID-19 might be as much as ten times as high as the official one. Any notion that the pandemic has bypassed Africa is, as Christopher Gill, an infectious-disease specialist at Boston University and another leader of the study, puts it, “a myth born of poor or absent data.” Underreporting was plainly a serious issue.
The data problem could be worse in some countries, better in others. We’d expect that the amount of undercounting would vary from place to place because public-health resources vary, too. Westerners often think of sub-Saharan Africa as an undifferentiated landscape of underdevelopment, but that’s far from the case. Zambia’s per-capita G.D.P. is just sixty per cent of Ghana’s or Nigeria’s. Burkina Faso’s is sixty per cent of Zambia’s.
What to do when you can’t take coroners’ reports at face value, assuming that you even have a coroner’s report? Public-health experts have a saying: “It’s hard to hide bodies.” So a surge of deaths under any description—“all-cause mortality”—might help us glimpse the true dimension of the problem.
What’s the story in India? I turned to Ajay Shah, a soft-spoken economist from New Delhi, who has performed a notably detailed analysis of deaths in India during the pandemic. Rather than relying on hospital data, Shah and his co-author, Renuka Sane, have used a longitudinal household survey, in which each household is assessed three times a year, to examine the number and the pattern of deaths. They found that the total number of “all cause” deaths reported between May and August almost doubled in India compared with the same period in each of the past five years.
“Is that because the number of COVID deaths in the country has been vastly underestimated?” I asked.
“It’s impossible to have a decisive answer,” Shah told me. “But the pattern of the excess deaths doesn’t really shout out COVID as the cause. It just doesn’t.” When his researchers analyzed the data by age, location, and gender, they found that excess deaths tended to be observed in younger cohorts, and in rural rather than in urban settings; nor was there evidence of the usual coronavirus skew toward greater lethality in men. “The telltale signatures of COVID just aren’t there,” he said. He won’t venture any hypotheses about the cause of the excess deaths. But among the possible candidates are indirect consequences of the pandemic: wage loss, displacement, malnourishment, forced migration, and disruptions in health care—the skipped clinic visit for malaria, diabetes, TB, or hypertension. According to World Health Organization analyses, disruptions in medical care and prevention programs related to malaria, TB, and H.I.V. will have cost many more lives in sub-Saharan Africa in the past year than the coronavirus. In poorer regions, especially, infection isn’t the only way that the pandemic can cost lives.
What if the storm simply hasn’t yet arrived in the countries reporting oddly low death rates from COVID-19? Patrick Walker, another Imperial College epidemiologist and modeller, cautioned, “There’s a time element that has not been built into the model. There have been waves after the first wave, and we still don’t know how many deaths each wave might carry.” It’s certainly true that, in much of the Global South, reported COVID-19 deaths have risen substantially this season. To what extent have low-mortality regions simply avoided exposure to the pandemic?
In July and August, the health economist Manoj Mohanan and a team of researchers set out to estimate the number of people who had been infected with the new coronavirus in Karnataka, a state of sixty-four million people in southwest India. Random sampling revealed that seroprevalence—the rate of individuals who test positive for antibodies—was around forty-five per cent, indicating that nearly half the population had been infected at some point. Findings from a government survey last year showed that thirteen per cent of the population was actively infected in September. A large-scale survey in New Delhi, according to a recent government report, found a seroprevalence level of fifty-six per cent, suggesting that about ten million of its residents had been infected.
It’s difficult to get seroprevalence numbers for Nigeria, say, but it’s far from a secluded enclave; in 2019, it had an estimated twelve thousand Chinese workers, and, in a typical year, millions of people fly in and out of the country and within it. “Oh, there is probably a lot of endemic COVID transmission going on over here,” Fasina, in Lagos, told me. “But we are just not seeing the extreme severity.” (Most African deaths, the W.H.O. finds, are associated with such risk factors as hypertension and Type 2 diabetes.) In Niger State, which is the largest in Nigeria and is situated in the middle of the country, a seroprevalence study conducted in June found an infection rate of twenty-five per cent, comparable to the worst-hit areas in the United States. Fasina expects that the rate in Lagos and its surroundings will be higher. Nearly a year after Nigeria confirmed its first infections from the new coronavirus, Niger State has reported fewer than twenty deaths. The country’s numbers are climbing—but they’ll need to grow exponentially in order to catch up with the models.
Some epidemiologists argue that an accurate account of geographical disparities must give due weight to another extrinsic factor: certain governments have responded more effectively to the crisis than others. Bethany Hedt, a statistician at Harvard Medical School, has worked in Rwanda for the past decade. She noted that in 2020 the low-income country reported only a hundred-some deaths from COVID-19, out of a population of thirteen million. “It’s clear to me, at least,” she said, “that it’s because the government had very clear and decisive control measures.” She went on, “When news of COVID hit, they imposed a strict curfew, and the Rwandan population really listened. There was limited travel outside the home without documentation. The police would stop you and check. Schools were closed. There were no weddings or funerals. And then, as the numbers decreased, the government played a very good game of whack-a-mole. They have a really strong data center, and anywhere they see an outbreak they do strict control at the local level.”
Mohanan, the health economist who led the Karnataka study, agreed that, in some places, “decisive government action led to suppression of the pandemic.” In Dharavi, health-care workers rightly take pride in their heroic efforts to track, trace, and contain infection. But the vigorous implementation of public-health measures was far from the norm in much of Africa and the Indian subcontinent. “If anything, India’s response is a textbook case of what not to do in a pandemic—overly aggressive policy responses combined with communication strategies that undermined the importance of public-health prevention,” Mohanan argued.
But what to make of the much discussed reports about how everyone in India started to wear masks this fall? My colleagues in India were doubtful about the reported level of compliance; they also noted that the recorded incidence of COVID-19 deaths in the country was creeping down almost as gradually as it had crept up, which didn’t signal an abrupt change in behavior. My mother (who is under strict instructions to wear a mask and maintain social distance) routinely sends me pictures of gatherings in Delhi with dozens of maskless minglers.