We keep hearing that blacks and hispanics are disproportionate among the people contracting and succumbing to COVID-19 in the U.S., and at the moment this is taken as yet another sign of America’s “systemic racism” and perverse inequality. You’re not allowed to ask whether blacks and hispanics suffer from higher co-morbidity factors (especially being overweight), or to adjust the infection and fatality rates for age, population density, and income. Lower income people (of any race) tend to live in higher densities, and as such would be more exposed to community spread. Is the problem race, or poverty? These days, you have to stick with race.
Which makes all the more interesting a study of COVID-19 rates in Africa just published in Science magazine. Here’s some of the article:
Although Africa reported its millionth official COVID-19 case last week, it seems to have weathered the pandemic relatively well so far, with fewer than one confirmed case for every thousand people and just 23,000 deaths so far. Yet several antibody surveys suggest far more Africans have been infected with the coronavirus—a discrepancy that is puzzling scientists around the continent. “We do not have an answer,” says immunologist Sophie Uyoga at the Kenya Medical Research Institute–Wellcome Trust Research Programme.
After testing more than 3000 blood donors, Uyoga and colleagues estimated in a preprint last month that one in 20 Kenyans aged 15 to 64—or 1.6 million people—has antibodies to SARS-CoV-2, an indication of past infection. That would put Kenya on a par with Spain in mid-May when that country was descending from its coronavirus peak and had 27,000 official COVID-19 deaths. Kenya’s official toll stood at 100 when the study ended. And Kenya’s hospitals are not reporting huge numbers of people with COVID-19 symptoms.
Other antibody studies in Africa have yielded similarly surprising findings. From a survey of 500 asymptomatic health care workers in Blantyre, Malawi, immunologist Kondwani Jambo of the Malawi–Liverpool Wellcome Trust Clinical Research Programme and colleagues concluded that up to 12.3% of them had been exposed to the coronavirus. Based on those findings and mortality ratios for COVID-19 elsewhere, they estimated that the reported number of deaths in Blantyre at the time, 17, was eight times lower than expected.
In other words, Africa has seen wide exposure to COVID, but few serious cases or deaths. Let me speculate on one factor that might explain the discrepancy. Having visited Kenya twice, I’ll merely say that you don’t see very many obese Kenyans. And I suspect that is true for much of Africa.