In the first months of the pandemic, it was feared that the COVID was destined to hit African states like a tsunami. Countries like Sierra Leone, which can count on three doctors for every 100,000 inhabitants and which are already severely tested by malaria, tuberculosis, HIV, Ebola and malnutrition, would have reported – it was said – a disastrous number of cases and deaths. It doesn’t seem to have happened that way. But it is not at all clear whether we can really talk about narrow escape.
The low rate of infections, hospitalizations and deaths from covids in West and Central Africa is one of the unsolved mysteries of the pandemic: is it simply due to the failure to register cases? If SARS-CoV-2 was less lethal in Africa than elsewhere, what factors protected the population? And if instead the pandemic had hit this as hard as other continents, how did we not notice it? The question is taken up in an article in the New York Times.
Many infections. There are no longer any doubts about the fact that the virus was able to circulate widely in Africa as well. Several studies covering almost all sub-Saharan African countries highlight the presence of anti-SARS-CoV-2 antibodies in two thirds of the population. And since only 14% of the inhabitants of these states have been vaccinated, what we observe are the immune defenses developed following the actual infection. According to a WHO analysis not yet published in peer-reviewwhich takes into account the whole of Africa, 65% of Africans had contracted the virus by the end of 2021. There have been infections, and how.
Young age. Why then so few deaths? One of the few convincing explanations concerns the demographic characteristics of the population. The age median (that is, that which is placed in the middle in the succession of values) of Africans is of 19 years; in Europe it is 43 years old and in the USA 38. In sub-Saharan Africa, two thirds of the population is under 25, and in this phase of life there has not yet been time to develop those diseases (diabetes, obesity, cardiovascular problems , cancer, chronic respiratory diseases) which increase the risk of contracting covid in a severe form. Young people more often experience mild or asymptomatic covid and this could explain the low number of cases reported.
Confrontation with India. Other hypotheses circulated were high temperatures, low population density in certain rural areas, limited availability of public transport and the coexistence of infections, such as malaria, Lassa fever or Ebola, which may have offered some form of additional protection (for antibodies or for maintained preventive behaviors). But the millions of deaths caused by the Delta variant in India make these explanations difficult to accept. After all, the median age of the population in India is 28, temperatures are high there too, and the incidence of malaria or other coronavirus infections is still high.
Few data available. It therefore remains to be thought that the deaths from covid in Africa have not been adequately counted. Research from Njala University in Sierra Leone found antibodies to the new coronavirus in 78% of the population, but the country has reported just 125 deaths from covid since the start of the pandemic. In part it could be due to a practically non-existent testing system, and in part by the fact that patients die at home, because of the distance from hospitals or because of the choice of relatives. According to the Economic Commission for Africa (ECA), sub-Saharan Africa would only be registered one death for every three covid.
But the impact of the virus in South Africa makes it difficult to think that other countries with more fragile health systems have been spared. In the nation that first identified the Omicron variant there were, between March 2020 and September 2021, 250,000 more deaths than would have occurred from natural causes, and all in correspondence with the waves of covid.
“If this is happening in South Africa, why should it be any different here?” He told al New York Times Lawrence Mwananyanda, an epidemiologist at Boston University and health advisor to the President of Zambia, a country with 18 million inhabitants and only 4,000 deaths from official covids. A study coordinated by Mwananyanda found traces of SARS-CoV-2 in 87% of the bodies present in the morgues of Zambian hospitals, and for theEconomist the excess deaths from covid in Africa since the start of the pandemic would be between 1 and 2.9 million.
Why hasn’t anyone noticed? The missed registration theory does not find consensus among scientists working on African territory. Apart from the reports, if the virus had been lethal as elsewhere, overcrowded hospitals, lack of coffins, mass funerals would have had to be seen, and this was not the case (excluding the case of South Africa). Bureaucracy may not keep up with an unusual number of deaths, but in many circumstances social perception was also lacking of those dead, in the local media and in circles of friends and acquaintances.
Is everyone worth vaccinating? And if the mystery is destined to remain unsolved for now, the low death rate is prompting some to rethink African health policies. According to John Johnson, vaccination advisor at Doctors Without Borders, the goal of vaccinating 70% of the African population might have made sense a year ago, when it was believed that it could stem the transmission of the virus.
But now that we know that the dream of herd immunity has vanished even in countries with high availability of doses, it would perhaps be worthwhile to protect only the most vulnerable, and to invest resources in other health emergencies such as malaria, polio, cholera, meningitis and food insecurity. This is assuming future covid variants are less lethal, as was the case with Omicron. But who can be sure?