Only one in almost 100 Covid-19 cases may have been detected in Africa and about two-thirds of the continent’s inhabitants may have been infected with the disease, the World Health Organization said.

The assessment, which is available as a pre-print under peer review and is based on about 150 studies published in 2020 and 2021, shows how underreported the impact of the disease on the world’s poorest continent may have been. Globally, one in 16 cases have been picked up on average, according to the WHO.

 
 
“In September 2021, rather than the reported 8.2 million cases, there were in fact 800 million infections,” Matshidiso Moeti, the WHO’s director for Africa, said on a conference call on Thursday. “This highlights the need for sustained levels of routine testing and surveillance going forward, if we’re going to be able to stay a step ahead of the pandemic.”

Africa, which initially failed to source adequate vaccinations and now is struggling to administer them, is the world’s least-vaccinated continent with just 16% of people on the continent having received a full course of inoculations. Weak health systems and the lack of surveillance has meant that only a quarter of a million deaths have been recorded as a result of the disease. That has stoked speculation, dismissed by most scientists, that Africans are less susceptible to Covid-19.

Anecdotal evidence has shown hospitals from Lagos to Dar es Salaam and Harare being swamped with patients exhibiting Covid-19 symptoms in the midst of infection waves.

Excess deaths, seen as a more accurate measure of Covid-19’s impact, exceed 300,000 in South Africa alone.

The proportion of Africans who had been infected with the disease surged from 3% in June 2020 to 65% by September last year, Moeti said. It’s likely that amount has increased since then, she said.

Exposure to the virus was higher in dense urban areas compared to less-populated rural areas. It also varied between Africa’s sub-regions, with seroprevalence highest in the eastern, western and central areas.

Social-protection measures such as masking and limits on gatherings are being relaxed across the continent and this may lead to more infections, she said.

“Our analysis is clear evidence of the continued significant circulation of the Covid-19 virus among the people on the continent,” Moeti said. “With this comes a heightened risk of more lethal variants that can overwhelm existing immunity. So vaccination remains our best defense.”