The potential effects of widespread community transmission of SARS-CoV-2 infection in the World Health Organization African Region: a predictive model

Abstract

The spread of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has been unprecedented in its speed and effects. Interruption of its transmission to prevent widespread community transmission is critical because its effects go beyond the number of COVID-19 cases and deaths and affect the health system capacity to provide other essential services. Highlighting the implications of such a situation, the predictions presented here are derived using a Markov chain model, with the transition states and country specific probabilities derived based on currently available knowledge. A risk of exposure, and vulnerability index are used to make the probabilities country specific. The results predict a high risk of exposure in states of small size, together with Algeria, South Africa and Cameroon. Nigeria will have the largest number of infections, followed by Algeria and South Africa. Mauritania would have the fewest cases, followed by Seychelles and Eritrea. Per capita, Mauritius, Seychelles and Equatorial Guinea would have the highest proportion of their population affected, while Niger, Mauritania and Chad would have the lowest. Of the World Health Organization's 1 billion population in Africa, 22% (16%–26%) will be infected in the first year, with 37 (29 – 44) million symptomatic cases and 150 078 (82 735–189 579) deaths. There will be an estimated 4.6 (3.6–5.5) million COVID-19 hospitalisations, of which 139 521 (81 876–167 044) would be severe cases requiring oxygen, and 89 043 (52 253–106 599) critical cases requiring breathing support. The needed mitigation measures would significantly strain health system capacities, particularly for secondary and tertiary services, while many cases may pass undetected in primary care facilities due to weak diagnostic capacity and non-specific symptoms. The effect of avoiding widespread and sustained community transmission of SARS-CoV-2 is significant, and most likely outweighs any costs of preventing such a scenario. Effective containment measures should be promoted in all countries to best manage the COVID-19 pandemic.

Reconciling model predictions with low reported cases of COVID-19 in Sub-Saharan Africa: insights from Madagascar

“…Pearson et al [ 25 ] predicted a similar epidemic size for Madagascar as our model in an unmitigated scenario, with 75% of the population and nearly 100,000 deaths. In contrast, an analysis led by the WHO [ 12 ] predicted a total case burden nearly one third of this size (26% of the population) and only a fraction of COVID-19-related deaths (1,500). This study assumed that the regional particularities of SSA will decrease disease transmission and fatality rates based on country-specific proxies for these factors, such as climate, transportation networks, and contact matrices.…”

“…The epidemiology-based explanations for low COVID-19 cases are based on considerations of well-established factors: warmer climates, younger age distributions, and lower contact rates due to lower population density and transportation infrastructure in rural areas [ 12 , 13 ]. In addition, there is considerable interest in the potential immune-mediated consequences from living in a system with greater exposure to other infectious diseases and related prophylaxis and therapeutics [ 14 ].…”

The COVID-19 Pandemic in Francophone West Africa: From the First Cases to Responses in Seven Countries

“…Four months after these estimates were made, it remains true that, compared to the rest of the world, the West African region does not seem to have suffered a major epidemic shock, especially if we compare the current situation with that experienced by some countries during the Ebola crisis [5,6]. The most recent models predict that the 22% of the population in the African continent could become infected with SARS-CoV-2 during the rst year of the pandemic, with approximately 150,000 deaths [7] and with peaks of contamination varying from one country to another [8]. The same researchers predict that Francophone West African countries will have few deaths related to the virus during the year: fewer than 800 in Benin, 1000 in Burkina Faso and just over 2200 in Senegal [7].…”

“…The most recent models predict that the 22% of the population in the African continent could become infected with SARS-CoV-2 during the rst year of the pandemic, with approximately 150,000 deaths [7] and with peaks of contamination varying from one country to another [8]. The same researchers predict that Francophone West African countries will have few deaths related to the virus during the year: fewer than 800 in Benin, 1000 in Burkina Faso and just over 2200 in Senegal [7]. It has been estimated that the peak of cases in Senegal would occur between 28 May and 15 June 2020 [8].…”

Covid-19: No large hidden outbreak in Africa but health worker shortage worsens

“…A model published in BMJ Global Health in late May predicted that the WHO Africa region could see 83 000 to 190 000 deaths in the first year of the pandemic 1. That region does not include Egypt or most north African, Arabic speaking countries.…”