Africa’s COVID immunity is a medical mystery as mortality rates fall below early pandemic projections

Despite pessimistic projections that the coronavirus would cripple the African continent, it seems that wealthier and more well-equipped countries have higher death tolls and that the effect of COVID in Africa was comparatively minimal. 

Since the first recorded death in 2020, a whopping 1,883,711 people have died from COVID in Europe as of Mar. 13, according to Statista. In France specifically, 140,600 people have died from COVID, according to Statista. As of 2018 there were 6.5 doctors per 10,000 people in France, according to The World Bank. And even with over four times as many health professionals as an African country like Sierra Leone—there are 1.4 doctors, nurses and midwives per 10,000 people in the country as of 2019—over 99% more people died from the coronavirus in France than Sierra Leone. In Sierra Leone only 125 coronavirus-related deaths have been reported according to Reuters

And in Kamakwie, Sierra Leone in particular, the district’s COVID response center has registered a mere 11 cases since the beginning of the pandemic and no deaths, as reported by The New York Times

And it’s not just Sierra Leone that has a low death toll. Ghana has reported 1,445 deaths since the pandemic started, according to Reuters. Some countries in Africa are reporting coronavirus-related deaths that don’t even reach the four-figure mark, like Tanzania which has reported 800 COVID-related deaths since the start of the pandemic, and Togo which has reported 272 total coronavirus-related deaths. And one thing is for certain, the low COVID mortality rates in various African countries are not owed to incredibly widespread vaccine access. Vaccine inequity is an ongoing issue in many African countries like Uganda, Zambia, and more. Liberia, for example, has administered about 1.2 million doses of the COVID vaccine which would amount to about 12.2% of the country being vaccinated and yet has only reported 294 total coronavirus-related deaths.  On the other hand, a European country like Portugal has administered over 22 million doses of the COVID vaccine and is reportedly over 92% vaccinated, but still has reported 21,342 total coronavirus-related deaths.

As a result of this inescapable discrepancy, many are wondering: how are African countries faring better than other parts of the world?

Are African COVID deaths just not being recorded?

Some sources like WorldBank have asserted suspicions that African COVID death rates are heavily underreported given the scarcity of COVID tests and the fact that most coronavirus-related deaths occur at home. While it’s worth acknowledging that there may be issues with adequate testing for COVID-19 in some African countries, like Kenya and Zimbabwe for example,  a lack of case recording is likely not the culprit behind the fewer numbers of COVID-19 cases being reported, according to Dr. Andy Pekosz, a SARS-CoV-2 expert and the Vice Chair of the Molecular Microbiology & Immunology Department at Johns Hopkins University. 

“I think it’s quite clear that SARS-CoV-2 has been introduced into African countries on numerous occasions but in some cases, it’s not lead to outbreaks that are anywhere close to the scale we have seen elsewhere, including places like South America that lie on the same longitudinal lines as parts of Africa,” Pekosz told Fortune. 

Pekosz is more convinced that there is “certainly good enough monitoring of infectious diseases to have detected severe cases and deaths resulting from COVID-19,” and that the lack of coronavirus-related deaths in African countries is owed to something else.

If African COVID deaths aren’t underreported, where is the discrepancy coming from?

Because of “cross-reactive antibodies,” some scientists and researchers think that African countries that were exposed to Ebola and Lassa fever, such as Sierra Leone, have citizens with higher rates of resilience. For example, in a 2021 study, the blood samples of survivors of Ebola and Lassa fever in Sierra Leone had higher antibodies to seasonal coronaviruses than American blood donors, resulting in cross-protective immunity, according to Viruses, a peer-reviewed, open access journal of virology. 

Pekosz is aware of the cross-protective immunity argument but struggles to believe it wholeheartedly because of a lack of evidence. 

“There are a lot of theories about why we don’t see lots of COVID-19 in some African countries. The theory that there is some preexisting immunity that is dampening the effects of SARS-CoV-2 infection is one I hear often, but I have not seen any strong convincing data to support this,” Pekosz told Fortune. 

Pekosz believes that Lassa Fever and Ebola have not caused enough cases to generate immunity from COVID and therefore can’t be correlated to low case numbers in Africa. He believes that malaria has wide enough distribution to explain immunity, but has not been able to find a strong link to malaria and reduced COVID cases. 

“Furthermore, some studies of antibody levels in African countries haven’t shown a strong signal of preexisting antibodies to SARS-CoV-2,” Pekosz told Fortune. “It may be that parts of the immune response not related to antibodies could be contributing–perhaps cellular immune responses like T cell responses.” 

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