Possible Reasons Why Sub-Saharan Africa Experienced a Less Severe COVID-19 Pandemic in 2020

The COVID-19 pandemic response across much of sub-Saharan Africa has been uncoordinated - some governments have denied the infectivity and seriousness of the problem (eg, Tanzania),^1,2 and others have refused to implement global prevention strategies, but rather have promoted local cures and home remedies, while conducting business as usual (for example, Zambia and Madagascar).^3–5 Tanzania even refused COVID-19 vaccines, as the health minister announced that the country “has no plans in place to accept COVID-19 vaccines” following President John Magufuli expressing doubt about vaccines sourced abroad, without offering evidence.⁶

Despite the various missteps and the fact that Africa, as a whole, accounts for 25% of the global burden of diseases, the epidemic seems to have spared many sub-Saharan African countries to some degree in 2020, if the WHO case reporting is to be believed. At the time of writing, the African continent has had a lower COVID-19 prevalence, compared to the Americas and Europe.⁷ Although the situation is more serious in 2021 in Africa, as of July 6, 2021, of the 183,934,913 confirmed cases of COVID worldwide, only 4,224,102 (2.3%) have been reported in the continent; and of the 3,985,022 documented COVID-19 related deaths, only 98,718 (2.5%) have been reported in Africa⁷ – despite it being the second most populous continent after Asia, and despite having been negatively impacted by civil wars, hunger, diseases such as HIV-AIDS, tuberculosis and, in recent years, Ebola virus disease (EVD).^7,8 This low COVID-19 prevalence across much of the continent is despite the fact that mathematical models projected large COVID-19 epidemics as many African countries ostensibly had fewer means to suppress transmission and manage cases.⁸

It is of note that some African nations developed or swiftly reactivated some basic infrastructure like diagnostic testing facilities, intensive care units, surveillance, and systems for reporting emergencies to fight the COVID-19 pandemic; activated political and financial tools to combat the pandemic; and enjoyed a level of technical support from the Africa Centers for Disease Control and global development partners. However, the overall response was poorly coordinated and funded.⁸ In reality, the relative low reported impact of COVID-19 in the African continent in 2020 was not actually a result of an excellent, coordinated or thought-out response on behalf of governments or medical authorities in the African continent.^3,9,10 Although the situation is changing rapidly in 2021, the WHO recorded low case rates across the continent in 2020; we would hypothesise that the low reported COVID-19 rates in a swathe of sub-Saharan African countries in 2020 could be linked to:

1. Sub-Saharan African Disease Patterns: Although a majority of sub-Saharan African nations are battling with the triple burden of diseases – communicable, non-communicable and trauma/injuries, seasonal influenza is not common in across much of the continent.^11–15 Colds and catarrhal ailments may be seen during the dry seasons, but these do not normally translate into an epidemic in most sub-Saharan African nations, unlike in Europe and the Americas where influenza results in deaths of thousands of people annually.^16,17 Several environmental factors, such as the climate and the population distribution may negate the establishment and spread of influenza viruses. Such factors may have helped mitigate the extent of the COVID-19 pandemic in sub-Saharan Africa in 2020. Although there is increasing prevalence of COVID-19 in four different waves, the African continent still has the lowest number of documented cases at the time of writing.⁷
2. Sub-Saharan African Herd Immunity: Communicable diseases, including malaria, typhoid, and viral haemorrhagic fevers are still very common across the continent. In addition, a lack of adequate sanitation, a growing population of vectors, such as flies and mosquitoes, and a scarcity of drinkable water may expose the immune system of the average African to viral, bacterial, fungal, helminthic and protozoal agents that may stimulate the immune system without necessarily producing overt clinical disease.¹⁸ Repeated exposure over the years may help Africans to build active defences against common protozoal, bacterial and viral diseases, resulting in herd immunity and cross-immunity that may have protected a large proportion of the population from emerging and reemerging disease agents such as SARS-CoV-2.¹⁸ It has been argued that because people with malaria develop anti-GPI antibodies that may recognise SARS-CoV-2 glycoproteins, repeated malarial exposure may be protective against COVID-19 or bring about a milder disease pattern.¹⁹

Furthermore, with nearly 13% of the world population living in extreme poverty, the continent has the largest share of poor people worldwide.²⁰ Accompanying this level of poverty in sub-Saharan Africa, people frequently live in slums, shared space with multiple families in a single-family house, and many living in a classical congregate setting in proximity (although it could be argued that the same applies to parts of India). Beyond sharing space, people also share food, water, amenities, utensils and their diseases, resulting in diverse cross-immunity. The culture of shared space makes social distancing difficult, if not impossible. Close interaction, which was feared to have worsened the epidemic in America and Europe, rather that worsening the pandemic in sub-Saharan Africa, may have brought about low-level contemporaneous exposure to a number of infectious agents including SARS-CoV-2, resulting in cross-immunity against several infections, including against COVID-19.²⁰ It is, therefore, possible that space sharing, congregate living conditions and economic poverty may have contributed to a better pandemic outcome for sub-Saharan Africans with high-level herd immunity against multiple infections, which may have contributed significantly to the lower documented cases of COVID-19, as well as deaths associated with COVID-19 across much of the African continent in 2020.⁷

While death rates are now rising in 2021 across the African continent to levels not seen in 2020, this may be related to the emergence of new viral variants which have reduced the natural resistance of communities across the continent, such as the delta variant and/or to the lack of COVID-19 vaccination throughout Africa.⁷

We should be mindful that the COVID-19 pandemic has completely changed the way the world functions, how businesses are managed (with remote working), patients are cared for (with tele-health) and meetings are held (through video-conferencing). However, we will not reach an equilibrium until COVID-19 vaccination is widespread around the world. The potential for new viral variants to occur in unvaccinated populations is too great and currently, sub-Saharan Africa being a source of concern in this regard.³⁴ In sub-Saharan Africa, vaccination is going to become the next hurdle as vaccines are not widely available. As of July 12 2021, 3.44 billion doses have been delivered worldwide, but less than 0.5% of the total has been in the continent.³⁵ Where COVID-19 vaccines are available, such as in the Republic of South Africa, uptake is poor owing to vaccine hesitancy, skepticism, mistrust of the system, and poor/ineffective public health dissemination policies.³⁶ Public healthcare policies need to be directed towards education of the general public with respect to improving vaccine uptake and reducing vaccine skepticism.^37–40

While there is not a one-size-fits-all policy for the continent and this is apparent when focusing on countries such as the Republic of South Africa, which was harder hit by the pandemic,⁴¹ we believe that it will be good to review the current COVID pandemic comprehensively to document the mistakes made, the lessons learned, and to develop a global pandemic response protocol that will prepare governments, scientists and healthcare professionals for appropriate action in any future pandemics. Such lessons need to be reviewed in a multidisciplinary way (and not just from a medical perspective), as factors such as atmospheric stability, wind speed and environmental pollution all have had an impact on COVID-19 transmission and given that weather patterns are frequently predictable, such data should be added into public health models of disease transmission to more accurately forecast future trends across the continent, both in the current pandemic and in future potential disease outbreaks.⁴²