SARS-CoV-2 antibody seroprevalence and associated risk factors in an urban district in Cameroon

Seroprevalence and risk factors for SARS-CoV-2 infection in middle-sized cities of Burkina Faso: A descriptive cross-sectional study

BACKGROUND

Since March 2020, COVID-19 has evolved from a localized outbreak to a global pandemic. We assessed the seroprevalence of COVID-19 in three towns in the Centre Sud region of Burkina Faso.

METHODS

A population-based cross-sectional survey was conducted in three middle-sized cities in Burkina Faso's Centre Sud region, from June to July 2021. Subjects aged 16 or over at the time of the survey were considered for this seroprevalence study. The Biosynex COVID-19 BSS rapid test was used to detect immunoglobulin G (IgG) and immunoglobulin M (IgM) against SARS-CoV-2. A standardized questionnaire was also administered to collect additional information.

RESULTS

A total of 2449 eligible participants (age ≥ 16 years) were identified. Serological tests for COVID-19 were performed in 2155 individuals, of which 2143 valid tests were retained and analyzed. Out of the entire sample, 246 positive tests were observed, corresponding to a prevalence of 11.48%. Prevalence was 9.35% (58 cases) in Kombissiri, 12.86% (80 cases) in Manga and 11.99% (108 cases) in Pô. By gender, 13.37% of women (164 cases) tested positive, and 8.95% of men (82 cases). Women accounted for 66.67% of all positive test subjects. The results from the multivariate analysis show a significantly higher seroprevalence in women (p = 0.007), people over 55 years old (p = 0.004), overweight people (p = 0.026) and those with drinking water sources at home (p = 0.013).

CONCLUSIONS

The results of this study show that the COVID-19 virus also circulates in the population of middle-sized cities in Burkina Faso, far more than officially reported by the information service of the government of Burkina Faso, given the lack of systematic testing in the general population in the country. The study also highlighted the greater vulnerability of women, older and overweight individuals to the epidemic. The preventive measures put in place to fight the pandemic must take these different factors into account.

SARS-CoV-2 seroprevalence among Beninese pregnant women in the third year of the pandemic

BACKGROUND

Pregnant women are a vulnerable population to COVID-19 given an increased susceptibility to severe SARS-CoV-2 infection and pregnancy complications. However, few SARS-CoV-2 serological surveys have been performed among this population to assess the extent of the infection in sub-Saharan countries. The objectives of this study were to determine SARS-CoV-2 seroprevalence among Beninese pregnant women, to identify spatial seropositivity clusters and to analyse factors associated with the infection.

METHODS

A cross-sectional study including women in their third trimester of pregnancy attending the antenatal care (ANC) clinics at Allada (south Benin) and Natitingou (north Benin) was conducted. Rapid diagnostic tests (RDT) for detection of IgG/IgM against the SARS-CoV-2 spike protein were performed using capillary blood. Seroprevalence of SARS-CoV-2 antibodies and associations between SARS-CoV-2 serostatus and maternal characteristics were analyzed by multivariate logistic regression. Spatial analyses were performed using the spatial scan statistics to identify spatial clusters of SARS-CoV-2 infection.

RESULTS

A total of 861 pregnant women were enrolled between May 4 and June 29, 2022. 58/861 (6.7%) participants reported having received COVID-19 vaccine. None of the participants had been diagnosed with COVID-19 during their pregnancy. SARS-CoV-2 antibodies were detected in 607/802 (75.7%; 95% CI 72.56%-78.62%) of unvaccinated participants. Several urban and rural spatial clusters of SARS-CoV-2 cases were identified in Allada and one urban spatial cluster was identified in Natitingou. Unvaccinated participants from Allada with at least one previous morbidity were at a three-times higher risk of presenting SARS-CoV-2 antibodies (OR = 2.89; 95%CI 1.19%-7.00%).

CONCLUSION

Three out of four pregnant women had SARS-CoV-2 antibodies, suggesting a high virus circulation among pregnant women in Benin, while COVID-19 vaccination coverage was low. Pregnant women with comorbidities may be at increased risk of SARS-CoV-2 infection. This population should be prioritized for COVID-19 diagnosis and vaccination in order to prevent its deleterious effects.

TRIAL REGISTRATION

NCT06170320 (retrospectively registered on December 21, 2023).

Serological surveillance reveals a high exposure to SARS-CoV-2 and altered immune response among COVID-19 unvaccinated Cameroonian individuals

Surveillance of COVID-19/SARS-CoV-2 dynamics is crucial to understanding natural history and providing insights into the population's exposure risk and specific susceptibilities. This study investigated the seroprevalence of SARS-CoV-2 antibodies, its predictors, and immunological status among unvaccinated patients in Cameroon. A multicentre cross-sectional study was conducted between January and September 2022 in the town of Douala. Patients were consecutively recruited, and data of interest were collected using a questionnaire. Blood samples were collected to determine Immunoglobin titres (IgM and IgG), interferon gamma (IFN- γ) and interleukin-6 (IL-6) by ELISA, and CD4+ cells by flow cytometry. A total of 342 patients aged 41.5 ± 13.9 years were included. Most participants (75.8%) were asymptomatic. The overall crude prevalence of IgM and IgG was 49.1% and 88.9%, respectively. After adjustment, the seroprevalence values were 51% for IgM and 93% for IgM. Ageusia and anosmia have displayed the highest positive predictive values (90.9% and 82.4%) and specificity (98.9% and 98.3%). The predictors of IgM seropositivity were being diabetic (aOR = 0.23, p = 0.01), frequently seeking healthcare (aOR = 1.97, p = 0.03), and diagnosed with ageusia (aOR = 20.63, p = 0.005), whereas those of IgG seropositivity included health facility (aOR = 0.15, p = 0.01), age of 40-50 years (aOR = 8.78, p = 0.01), married (aOR = 0.21, p = 0.02), fever (aOR = 0.08, p = 0.01), and ageusia (aOR = 0.08, p = 0.01). CD4+, IFN-γ, and IL-6 were impaired in seropositive individuals, with a confounding role of socio-demographic factors or comorbidities. Although the WHO declared the end of COVID-19 as a public health emergency, the findings of this study indicate the need for continuous surveillance to adequately control the disease in Cameroon.

High seroprevalence of severe acute respiratory syndrome coronavirus 2 among healthcare workers in Yaoundé, Cameroon after the first wave of Covid-19 pandemic and associated factors

BACKGROUND

Healthcare workers (HWs) are at a high risk of exposure to emerging health threats. Following the first wave of the coronavirus disease 2019 pandemic in Cameroon, we explored the presence and persistence of naturally acquired antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the factors associated with seropositivity in HWs.

METHODS

Staff at two referral hospitals in Yaoundé or two Health District Hospitals in Obala and Mbalmayo were included in a 6-month prospective cohort analysis or cross-sectional survey, respectively. Seroprevalence and associated factors were determined, and Kaplan-Meier curves and Cox proportional hazards models were used to assess antibody persistence or positive seroconversion over time.

RESULTS

From August 2020 to March 2021, 426 HWs (median age: 31 years, interquartile range: 27-37 years; 66.4% female) were enrolled. The overall seroprevalence of anti-SARS-CoV-2 antibodies was 54.0% (95% confidence interval [CI]: 49.1-58.8) and was significantly different between study sites (p = 0.04). Of the 216 HWs included in the 6-month cohort, 109 (50.5%) HWs were seropositive at inclusion; the probability of persistent antibodies or of becoming seropositive was 93.8% (95% CI: 84.2-100) and 78.9% (95% CI: 61.7-88.4), respectively. Seroconversion was associated with study site and occupation but not with infection prevention and control (IPC) practices.

CONCLUSIONS

We observed high seroprevalence of SARS-CoV-2 antibody and seroconversion among HWs associated with occupational risk. This suggests low compliance to the COVID-19 control measures. Continued training and implementation of IPC measures and accelerated preparedness are needed to better tackle future threats.

COVID-19 preventive social-behavioural practices and exposure to SARS-CoV-2 among residents in the city of Yaounde: Lessons from the early phase of the pandemic in Cameroon

Non-pharmaceutical interventions remain key in mitigating the spread of SARS-CoV-2. We sought to assess COVID-19 preventive, social-behavioural practices, and SARS-CoV-2 exposure through IgG rapid tests. This was a cross-sectional survey among 971 respondents residing in 180 households within the "Cite Verte" health district of Yaounde-Cameroon, from October-November 2020. Using a structured questionnaire, data on SARS-CoV-2 preventive and social behavioural practices were collected, while exposure to SARS-CoV-2 was determined by IgG profiling. p<0.05 was considered statistically significant. Overall, 971 participants were enrolled, among whom 56.5% were females. The age group 15-29 (33.5%) and those with a secondary level of education (44.7%) were most represented. Regarding preventive/social behavioural practices, the least respected measure was "stopped work", 49.1%, while the most respected was "Respect of hygiene rules", 93.8%. Women obeyed preventive measures more than men, with 87.6% vs 81.0% adhering to the lockdown, (p = 0.005) and 95.5% vs 91.7% to hygiene rules (p = 0.017). The age range 45-64 years was the least adherent to the lockdown rule, with 75.2% (38/153), p<0.0001. Only 24.7% (73/295) and 6.1% (59/295) of the symptomatic individuals reported having sought medical consultation and Covid-19 testing respectively. In addition, up to 69.8% (555/795) felt healthcare facilities were high-risk sites for getting infected, p = 0.002. Exposure to SARS-CoV-2 by IgG positivity was 31.1% (302/971), with men recording a higher proportion of viral exposure, 51.0% (154/302), p = 0.021. After adjusting for gender, age, education, and occupation; salaried worker (p = 0.029; OR: 0.29), and trading (p = 0.001; OR: 0.23) least complied with lockdown rule. In this community of Cameroonian residents highly exposed to COVID-19, many perceived healthcare facilities as high-risk zones for SARS-CoV-2 infection and consequently did not seek medical interventions. Thus, in the context of such a pandemic, advocacy on risk communication and community engagement for health-seeking attitudes should preferentially target men and those afraid of pandemics.

Seroprevalence of anti-SARS-CoV-2 IgG antibodies in HIV-positive and HIV-negative patients in clinical settings in Douala, Cameroon

Background

The asymptomatic nature of COVID-19 coupled with differential testing are confounders in the assessment of SARS-CoV-2 incidence among people living with HIV (PLWH). As various comorbidities increase the risk of SARS-CoV-2 infection, it is crucial to assess the potential contribution of HIV to the risk of acquiring COVID-19. Our study aimed to compare the anti-SARS-CoV-2 IgG seroprevalence among people living with and without HIV.

Methods

PLWH were enrolled in the HIV units of two health facilities in Douala, Cameroon. Participants were consecutively enrolled, among which 47 were people living with HIV and 31 were HIV-negative patients. SARS-CoV-2 antibody tests were performed on all participants. Overall, medical consultation was conducted. For HIV-positive participants only, viral load, antiretroviral regimen, duration of HIV infection, and duration of antiretroviral treatment were retrieved from medical records.

Results

We found an overall SARS-CoV-2 IgG seroprevalence of 42.31% within the study population, with a SARS-CoV-2 IgG seroprevalence of 44.6% for PLWH and 38.7% among those without HIV infection; no significant statistical difference was observed. Adjusting for sex, HIV status, and BCG vaccination, the odds of previous SARS-CoV-2 infection were higher among married persons in the study population. Sex, BCG vaccination, and HIV status were not found to be associated with SARS-CoV-2 IgG seropositivity.

Conclusions

Our findings support the lack of association between HIV status and susceptibility to SARS-CoV-2 infection. The ARV regimen, suppressed viral load, and Tenofovir boasted ARV regimen might not affect the body's immune response after exposure to SARS-CoV-2 among PLWH. Thus, if HIV is well treated, the susceptibility to COVID-19 in PLWH would be like that of the general population.

Sero-prevalence of anti-SARS-CoV-2 antibodies among communities between July and August 2022 in Bangui, Central African Republic

Background

Large-scale population-based seroprevalence studies of SARS-CoV-2 are essential to characterize the cumulative incidence of SARS-CoV-2 infection and to extrapolate the prevalence of presumptive immunity at the population level. Objective. The objective of our survey was to estimate the cumulative population immunity for COVID-19 and to identify individual characteristics associated with positive serostatus.

Materials and Methods

This was a clustered cross-sectional study conducted from July 12 to August 20, 2021, in households in the city of Bangui, the capital of the Central African Republic. Information regarding demographic characteristics (age, gender, and place of residence), and comorbidities (chronic diseases) was collected. A venous blood sample was obtained from each participant to determine the level of total anti-SARS-CoV-2 antibodies using a WANTAI SARS-CoV-2 Ab ELISA kit.

Results

All up, 799 participants were surveyed. The average age was 27 years, and 45.8% of the respondents were male (sex ratio: 0.8). The overall proportion of respondents with positive serostatus was 74.1%. Participants over 20 years of age were twice as likely to have positive serostatus, with an OR of 2.2 [95% CI: (1.6, 3.1)].

Conclusions

The results of this survey revealed a high cumulative level of immunity in Bangui, thus indicating a significant degree of spread of SARS-CoV-2 in the population. The public health implications of this immunity to SARS-CoV-2 such as the post-vaccination total antibody kinetics remain to be determined.

Spread of SARS-CoV-2 Infection in Adult Populations in Cameroon: A Repeated Cross-Sectional Study Among Blood Donors in the Cities of Yaoundé and Douala

Over a period of about 9 months, we conducted three serosurveys in the two major cities of Cameroon to determine the prevalence of SARS-COV-2 antibodies and to identify factors associated with seropositivity in each survey. We conducted three independent cross-sectional serosurveys of adult blood donors at the Central Hospital in Yaoundé (CHY), the Jamot Hospital in Yaoundé (JHY) and at the Laquintinie Hospital in Douala (LHD) who consented in writing to participate. Before blood sampling, a short questionnaire was administered to participants to collect their sociodemographic and clinical characteristics. We included a total of 743, 1202, and 1501 participants in the first (January 25-February 15, 2021), second (May 03-28, 2021), and third (November 29-December 31, 2021) surveys, respectively. The adjusted seroprevalence increased from 66.3% (95% CrI 61.1-71.3) in the first survey to 87.2% (95% CrI 84.0-90.0) in the second survey, and 98.4% (95% CrI 96.8-99.7) in the third survey. In the first survey, study site, participant occupation, and comorbid conditions were associated with SARS-CoV-2 seropositivity, whereas only study site remained associated in the second survey. None of the factors studied was significantly associated with seropositivity in the third survey. Together, the data suggest a rapid initial spread of SARS-CoV-2 in the study population, independent of the sociodemographic parameters assessed.

Modeling SARS-CoV-2 antibody seroprevalence and its determinants in Ghana: A nationally representative cross-sectional survey

Estimates of SARS-CoV-2 transmission rates have significant public health policy implications since they shed light on the severity of illness in various groups and aid in strategic deployment of diagnostics, treatment and vaccination. Population-based investigations have not been conducted in Ghana to identify the seroprevalence of SARS-CoV-2. We conducted an age stratified nationally representative household study to determine the seroprevalence of SARS-CoV-2 and identify risk factors between February and December 2021. Study participants, 5 years and older regardless of prior or current infection COVID-19 infection from across Ghana were included in the study. Data on sociodemographic characteristics, contact with an individual with COVID-19-related symptoms, history of COVID-19-related illness, and adherence to infection prevention measures were collected. Serum obtained was tested for total antibodies with the WANTAI ELISA kit. The presence of antibodies against SAR-COV-2 was detected in 3,476 of 5,348 participants, indicating a seroprevalence of 67.10% (95% CI: 63.71-66.26). Males had lower seroprevalence (65.8% [95% CI: 63.5-68.04]) than females (68.4% [95% CI: 66.10-69.92]). Seroprevalence was lowest in >20 years (64.8% [95% CI: 62.36-67.19]) and highest among young adults; 20-39 years (71.1% [95% CI 68.83,73.39]). Seropositivity was associated with education, employment status and geographic location. Vaccination status in the study population was 10%. Exposure is more likely in urban than rural areas thus infection prevention protocols must be encouraged and maintained. Also, promoting vaccination in target groups and in rural areas is necessary to curb transmission of the virus.

Epidemiological situation of SARS-CoV-2 infection in Douala, the most populated and highly heterogeneous town of Cameroon: a post-vaccination update

This study aimed at providing an update of SARS-CoV-2 epidemiology in Douala, the most populated and highly heterogeneous town of Cameroon. A hospital-based cross sectional study was conducted from January to September 2022. A questionnaire was used to collect sociodemographic, anthropometric, and clinical data. Retrotranscriptase quantitative polymerase chain reaction was used to detect SARS-CoV-2 in nasopharyngeal samples. Of the 2354 individuals approached, 420 were included. The mean age of patients was 42.3 ± 14.4 years (range 21 - 82). The prevalence of SARS-CoV-2 infection was 8.1%. The risk of infection with SARS-CoV-2 was increased more than seven times in patients aged ≥ 70 years old (aRR = 7.12, p = 0.001), more than six times in married (aRR = 6.60, p = 0.02), more than seven times in those having completed secondary studies (aRR = 7.85, p = 0.02), HIV-positive patients (aRR = 7.64, p < 0.0001) and asthmatic patients (aRR = 7.60, p = 0.003), and more than nine times in those seeking health care regularly (aRR = 9.24, p = 0.001). In contrast, the risk of SARS-CoV-2 infection was reduced by 86% in patients attending Bonassama hospital (aRR = 0.14, p = 0.04), by 93% in patients of blood group B (aRR = 0.07, p = 0.04), and by 95% in COVID-19 vaccinated participants (aRR = 0.05, p = 0.005). There is need for ongoing surveillance of SARS-CoV-2 in Cameroon, given the position and importance of Douala.

Pre-existing immunity to SARS-CoV-2 before the COVID-19 pandemic era in Cameroon: A comparative analysis according to HIV-status

Background

The lower burden of COVID-19 in tropical settings may be due to preexisting cross-immunity, which might vary according to geographical locations and potential exposure to other pathogens. We sought to assess the overall prevalence of SARS-CoV-2 antibodies and determine SARS-CoV-2 seropositivity according to HIV-status before the COVID-19 pandemic era.

Methods

A cross-sectional and comparative study was conducted at the Chantal BIYA International Reference Centre (CIRCB) on 288 stored plasma samples (163 HIV-positive versus 125 HIV-negative); all collected in 2017-2018, before the COVID-19 pandemic era. Abbott Panbio™ COVID-19 IgG/IgM assay was used for detecting SARS-CoV-2 immunoglobulin G (IgG) and M (IgM). Among people living with HIV (PLHIV), HIV-1 viral load and TCD4 cell count (LTCD4) were measured using Abbott Real Time PCR and BD FACSCalibur respectively. Statistical analyses were performed, with p<0.05 considered statistically significant.

Results

The median [IQR] age was 25 [15-38] years. Overall seropositivity to SARS-CoV-2 antibodies was 13.5% (39/288) of which 7.3% (21) was IgG, 7.3% (21) IgM and 1.0% (3) IgG/IgM. According to HIV-status in the study population, SARS-CoV-2 seropositivity was 11.0% (18/163) among HIV-positive versus 16.8% (21/125) among HIV-negative respectively, p=0.21. Specifically, IgG was 6.1% (10/163) versus 8.8% (11/125), p=0.26; IgM was 5.5% (9/163) versus 9.6%, (12/125), p=0.13 and IgG/IgM was 0.6% (1/163) versus 1.6% (2/125) respectively. Among PLHIV, SARS-CoV-2 seropositivity according to CD4 count was 9.2% (≥500 cells/µL) versus 1.8% (200-499 cells/µL), (OR=3.5; p=0.04) and 0.6% (<200 cells/µL), (OR=17.7; p<0.01). According to viral load, SARS-CoV-2 seropositivity was 6.7% (≥40 copies/mL) versus 4.9% (<40 copies/mL), (OR= 3.8; p<0.01).

Conclusion

Before COVID-19 in Cameroon, cross-reactive antibodies to SARS-CoV-2 were in circulation, indicating COVID-19 preexisting immunity. This preexisting immunity may contribute in attenuating disease severity in tropical settings like Cameroon. Of relevance, COVID-19 preexisting immunity is lower with HIV-infection, specifically with viral replication and poor CD4-cell count. As poor CD4-count leads to lower cross-reactive antibodies (regardless of viral load), people living with HIV appear more vulnerable to COVID-19 and should be prioritized for vaccination.

Observed versus estimated actual trend of COVID-19 case numbers in Cameroon: A data-driven modelling

Controlling the COVID-19 outbreak remains a challenge for Cameroon, as it is for many other countries worldwide. The number of confirmed cases reported by health authorities in Cameroon is based on observational data, which is not nationally representative. The actual extent of the outbreak from the time when the first case was reported in the country to now remains unclear. This study aimed to estimate and model the actual trend in the number of COVID -19 new infections in Cameroon from March 05, 2020 to May 31, 2021 based on an observed disaggregated dataset. We used a large disaggregated dataset, and multilevel regression and poststratification model was applied prospectively for COVID-19 cases trend estimation in Cameroon from March 05, 2020 to May 31, 2021. Subsequently, seasonal autoregressive integrated moving average (SARIMA) modeling was used for forecasting purposes. Based on the prospective MRP modeling findings, a total of about 7450935 (30%) of COVID-19 cases was estimated from March 05, 2020 to May 31, 2021 in Cameroon. Generally, the reported number of COVID-19 infection cases in Cameroon during this period underestimated the estimated actual number by about 94 times. The forecasting indicated a succession of two waves of the outbreak in the next two years following May 31, 2021. If no action is taken, there could be many waves of the outbreak in the future. To avoid such situations which could be a threat to global health, public health authorities should effectively monitor compliance with preventive measures in the population and implement strategies to increase vaccination coverage in the population.

Comparative Performance of Serological (IgM/IgG) and Molecular Testing (RT-PCR) of COVID-19 in Three Private Universities in Cameroon during the Pandemic

BACKGROUND

COVID-19 remains a rapidly evolving and deadly pandemic worldwide. This necessitates the continuous assessment of existing diagnostic tools for a robust, up-to-date, and cost-effective pandemic response strategy. We sought to determine the infection rate (PCR-positivity) and degree of spread (IgM/IgG) of SARS-CoV-2 in three university settings in Cameroon Method: Study volunteers were recruited from November 2020 to July 2021 among COVID-19 non-vaccinated students in three Universities from two regions of Cameroon (West and Centre). Molecular testing was performed by RT-qPCR on nasopharyngeal swabs, and IgM/IgG antibodies in plasma were detected using the Abbott Panbio IgM/IgG rapid diagnostic test (RDT) at the Virology Laboratory of CREMER/IMPM/MINRESI. The molecular and serological profiles were compared, and p < 0.05 was considered statistically significant.

RESULTS

Amongst the 291 participants enrolled (mean age 22.59 ± 10.43 years), 19.59% (57/291) were symptomatic and 80.41% (234/291) were asymptomatic. The overall COVID-19 PCR-positivity rate was 21.31% (62/291), distributed as follows: 25.25% from UdM-Bangangte, 27.27% from ISSBA-Yaounde, and 5% from IUEs/INSAM-Yaounde. Women were more affected than men (28.76% [44/153] vs. 13.04% [18/138], p < 0.0007), and had higher seropositivity rates to IgM+/IgG+ (15.69% [24/153] vs. 7.25% [10/138], p < 0.01). Participants from Bangangté, the nomadic, and the "non-contact cases" primarily presented an active infection compared to those from Yaoundé (p= 0.05, p = 0.05, and p = 0.01, respectively). Overall IgG seropositivity (IgM-/IgG+ and IgM+/IgG+) was 24.4% (71/291). A proportion of 26.92% (7/26) presenting COVID-19 IgM+/IgG- had negative PCR vs. 73.08% (19/26) with positive PCR, p < 0.0001. Furthermore, 17.65% (6/34) with COVID-19 IgM+/IgG+ had a negative PCR as compared to 82.35% with a positive PCR (28/34), p < 0.0001. Lastly, 7.22% (14/194) with IgM-/IgG- had a positive PCR.

CONCLUSION

This study calls for a rapid preparedness and response strategy in higher institutes in the case of any future pathogen with pandemic or epidemic potential. The observed disparity between IgG/IgM and the viral profile supports prioritizing assays targeting the virus (nucleic acid or antigen) for diagnosis and antibody screening for sero-surveys.

The COVID-19 wave was already here: High seroprevalence of SARS-CoV-2 antibodies among staff and students in a Cameroon University

Background

Seroprevalence studies, to estimate the proportion of people that has been infected by SARS-CoV-2 are importance in African countries, where incidence is among the lowest in the world.

Objective

This study aimed at evaluating the exposure to SARS-CoV-2 within a university setting of Cameroon.

Methods

A cross-sectional study performed in December 2020 - December 2021, among students and staffs of the Evangelical University of Cameroon. COVID-19 antigen rapid detection test (RDT) was performed using Standard Q Biosensor, and one year after SARS-CoV-2 antibody-test was performed within the same population using RDT and chemiluminescence immunoassay (CLIA).

Results

106 participants were enrolled (80% students), female sex was the most represented. Positivity to SARS-CoV-2 was 0.0% based on antigen RDTs. The seroprevalence of SARSCoV- 2 antibodies was estimated at 73.6% (95% CI. 64.5-81.0) for IgG and 1.9% (95% CI. 0.2-6.8) for IgM/IgG with RDTs, and 91.9% (95% CI. 84.7-96.4) for anti-nucleocapsid with CLIA. 95.3% (101) reported having developed at least one of the known COVID-19 symptoms (cough and headache being the most common). 90.3% (28) of people who experienced at least one of these symptoms developed IgG antibodies. 40.6% (43) of participants took natural herbs, whereas 55.7% (59) took conventional drugs. The most used herb was Zingiber officinale, while the most used drugs were antibiotics.

Conclusion

In this Cameroonian University community, SARS-CoV-2 seroprevalence is high, with a greater detection using advanced serological assays. This indicates a wide viral exposure, and the need to adequate control measures especially for those experiencing any related COVID-19 symptoms.

High seroprevalence of anti-SARS-CoV-2 antibodies in the capital of Chad

Background. Since the start of the COVID-19 pandemic, Chad has had 7,417 confirmed cases and 193 deaths, one of the lowest in Africa. Objective. This study assessed SARS-CoV-2 immunity in N’Djamena. Methods. In August-October 2021, eleven N’Djamena hospitals collected outpatient data and samples. IgG antibodies against SARSCoV- 2 nucleocapsid protein were identified using ELISA. “Bambino Gesù” Laboratory, Rome, Italy, performed external quality control with chemiluminescence assay. Results. 25-34-year-old (35.2%) made up the largest age group at 31.9 12.6 years. 56.4% were women, 1.3 women/men. The 7th district had 22.5% and the 1st 22.3%. Housewives and students dominated. Overall seroprevalence was 69.5% (95% CI: 67.7-71.3), females 68.2% (65.8-70.5) and males 71.2% (68.6-73.8). >44-year-old had 73.9% seroprevalence. Under-15s were 57.4% positive. Housewives (70.9%), civil servants (71.5%), and health workers (9.7%) had the highest antibody positivity. N’Djamena’s 9th district had 73.1% optimism and the 3rd district had 52.5%. Seroprevalences were highest at Good Samaritan Hospital (75.4%) and National General Referral Hospital (74.7%). Conclusion. Our findings indicate a high circulation of SARSCoV- 2 in N’Djamena, despite low mortality and morbidity after the first two COVID-19 pandemic waves. This high seroprevalence must be considered in Chad’s vaccine policy.

High Severe Acute Respiratory Syndrome Coronavirus 2 Antibody Prevalence After the Third Epidemic Wave (May-October 2021) in Matadi, Democratic Republic of the Congo

Background

By the end of the third wave of the coronavirus disease 2019 (COVID-19) epidemic (May-October 2021), only 3130 of the 57 268 confirmed cases of coronavirus disease 2019 (COVID-19) in the Democratic Republic of the Congo (DRC) were reported in Kongo Central. This province, and especially its capital city, Matadi, has essential trade and exchanges with Kinshasa, the epicenter of the COVID-19 epidemic in DRC. Kinshasa accounted for 60.0% of all cases during the same period. The true burden of COVID-19 in Matadi is likely underestimated. In this study, we aimed to determine the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) seroprevalence and associated risk factors after the third wave in Matadi.

Methods

We conducted a population-based cross-sectional study in October 2021. Consenting participants were interviewed and tested using an enzyme-linked immunosorbent assay commercial kit. We applied univariable and multivariable analysis to evaluate factors associated with seropositivity and adjusted the seroprevalence for the test kit performance.

Results

We included 2210 participants from 489 households. Female participants represented 59.1%. The median age was 27 years (interquartile range, 16-45 years). The crude SARS-CoV-2 seroprevalence was 82.3%. Age was identified as the main risk factor as younger age decreased the seropositivity odds. Accounting for clustering at the household level increased the seroprevalence to 83.2%. The seroprevalence increased further to 88.1% (95% confidence interval, 86.2%-90.1%) after correcting for the laboratory test kit performance.

Conclusions

The SARS-CoV-2 seroprevalence was very high, contrasting with reported cases. Evidence generated from this population-based survey remains relevant in guiding the local COVID-19 response, especially vaccination strategies.

Dynamics of SARS-CoV-2 exposure in Malawian infants between February 2020 and May 2021

Background

Very limited information is available on SARS-CoV-2 seroprevalence in infants in sub-Saharan countries.

Objective

In this study, we aimed to determine the rate and the temporal evolution of SARS CoV-2 seropositivity in breastfed Malawian infants.

Study design

Blood samples (n = 250) from 158 infants, born to HIV-negative women and women living with HIV, collected from February 2020 to May 2021, were first tested using an Anti-IgG/A/M SARS CoV 2 ELISA assay against trimeric spike protein, and then, if positive, confirmed using a second ELISA assay detecting IgG against Receptor Binding Domain.

Results

The confirmed prevalence of anti-SARS CoV-2 antibodies was 31.0% (95% CI: 23.7%-38.3%) with no significant difference between HIV-exposed and HIV-unexposed infants (29.3% and 37.1% respectively, P = 0.410). The presence of anti-SARS-CoV-2 IgG was not associated with maternal socioeconomic or demographic indices.

Conclusions

Our data underline the wide spread of the SARS-CoV-2 infection in the pediatric population in sub-Saharan Africa. Design of more specific serological tests for African samples and improvements in serosurveillance programs are needed for more rigorous monitoring of the dynamics of SARS-CoV-2 infection in Africa.

Leveraging Serosurveillance and Postmortem Surveillance to Quantify the Impact of Coronavirus Disease 2019 in Africa

BACKGROUND

The coronavirus disease 2019 (COVID-19) pandemic has had a devastating impact on global health, the magnitude of which appears to differ intercontinentally: For example, reports suggest that 271 900 per million people have been infected in Europe versus 8800 per million people in Africa. While Africa is the second-largest continent by population, its reported COVID-19 cases comprise <3% of global cases. Although social and environmental explanations have been proposed to clarify this discrepancy, systematic underascertainment of infections may be equally responsible.

METHODS

We sought to quantify magnitudes of underascertainment in COVID-19's cumulative incidence in Africa. Using serosurveillance and postmortem surveillance, we constructed multiplicative factors estimating ratios of true infections to reported cases in Africa since March 2020.

RESULTS

Multiplicative factors derived from serology data (subset of 12 nations) suggested a range of COVID-19 reporting rates, from 1 in 2 infections reported in Cape Verde (July 2020) to 1 in 3795 infections reported in Malawi (June 2020). A similar set of multiplicative factors for all nations derived from postmortem data points toward the same conclusion: Reported COVID-19 cases are unrepresentative of true infections, suggesting that a key reason for low case burden in many African nations is significant underdetection and underreporting.

CONCLUSIONS

While estimating the exact burden of COVID-19 is challenging, the multiplicative factors we present furnish incidence estimates reflecting likely-to-worst-case ranges of infection. Our results stress the need for expansive surveillance to allocate resources in areas experiencing discrepancies between reported cases, projected infections, and deaths.

SARS CoV-2 Seroprevalence in Selected States of High and Low Disease Burden in Nigeria

IMPORTANCE

The global impact of COVID-19 has led to an increased need to continuously assess disease surveillance tools. The utility of SARS-CoV-2 serologic tools in determining immunity levels across different age groups and locations in helping to quickly assess the burden of COVID-19 with significant health policy implications is unknown.

OBJECTIVE

To determine the prevalence of SARS-CoV-2 antibodies with respect to the age group and sex of participants.

DESIGN, SETTING, AND PARTICIPANTS

A cross-sectional survey of 4904 individuals across 12 states with high and low COVID-19 disease burden in Nigeria was carried out between June 29 and August 21, 2021.

MAIN OUTCOMES AND MEASURES

Enzyme-linked immunosorbent assay was used for the detection of specific SARS-CoV-2 immunoglobulin G and immunoglobulin M antibodies, such as the nucleocapsid protein-NCP and spike protein S1. Interviewer-administered questionnaires provided information on participants' history of disease and associated risk factors.

RESULTS

A total of 4904 individuals participated in the study (3033 were female [61.8%]; mean [SD] age, 26.7 [6.51] years). A high seroprevalence of SARS-CoV-2 (78.9%) was obtained. Seropositivity was consistent across the states surveyed, ranging from 69.8% in Lagos to 87.7% in Borno. There was no association between sex and seropositivity (female, 2414 [79.6%]; male, 1456 [77.8%]; P = .61); however, an association was noted between age and seropositivity, with the peak prevalence observed in participants aged 15 to 19 years (616 [83.6%]; P = .001). Similarly, loss of appetite (751 [82.3%]; P = .04) and smell (309 [84.4%]; P = .01) were associated with seropositivity.

CONCLUSIONS AND RELEVANCE

In this cross-sectional study, a high SARS-CoV-2 seroprevalence was obtained among the study population during the low level of vaccination at the time of the survey. Thus, there is a need for both an efficacy and antibody neutralization test study to ascertain the efficacy of the antibody detected and the potential for herd immunity in Nigeria.

Prevalence of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Antibodies in the Mozambican Population: A Cross-Sectional Serologic Study in 3 Cities, July-August 2020

BACKGROUND

The extent of population exposure to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was uncertain in many African countries during the onset of the pandemic.

METHODS

We conducted a cross-sectional study and randomly selected and surveyed general population and occupational groups from 6 July to 24 August 2020, in 3 cities in Mozambique. Anti-SARS-CoV-2-specific immunoglobulin M (IgM) and immunoglobulin G (IgG) antibodies were measured using a point-of-care rapid test. The prevalence was weighted for population (by age, sex, and city) and adjusted for test sensitivity and specificity.

RESULTS

A total of 21 183 participants, including 11 143 from the general population and 10 040 from occupational groups, were included across all 3 cities. General population seropositivity (IgM or IgG) prevalence was 3.0% (95% confidence interval [CI], 1.0%-6.6%) in Pemba, 2.1% (95% CI, 1.2%-3.3%) in Maputo City, and 0.9% (95% CI, .1%-1.9%) in Quelimane. The prevalence in occupational groups ranged from 2.8% (95% CI, 1.3%-5.2%) to 5.9% (95% CI, 4.3%-8.0%) in Pemba, 0.3% (95% CI, .0%-2.2%) to 4.0% (95% CI, 2.6%-5.7%) in Maputo City, and 0.0% (95% CI, .0%-.7%) to 6.6% (95% CI, 3.8%-10.5%) in Quelimane, and showed variations between the groups tested.

CONCLUSIONS

In the first representative COVID-19 serosurveys in Mozambique, in mid-2020, weighted and assay-adjusted seroprevalence in 3 provincial capitals of anti-SARS-CoV-2 ranged from 0.9% to 3.0%, whereas adjusted prevalence in occupational groups ranged from 0.0% to 6.6% with variation between groups. Exposure to SARS-CoV-2 was extensive during the first pandemic wave, and transmission may have been more intense among occupational groups. These data have been of utmost importance to inform public health intervention to control and respond to the pandemic in Mozambique.

Seroprevalence of SARS-CoV-2 Antibodies in Africa: A Systematic Review and Meta-Analysis

A reliable estimate of SARS-CoV-2-specific antibodies is increasingly important to track the spread of infection and define the true burden of the ongoing COVID-19 pandemic. A systematic review and a meta-analysis were conducted with the objective of estimating the seroprevalence of SARS-CoV-2 infection in Africa. A systematic search of the PubMed, Scopus, Web of Science and Google Scholar electronic databases was conducted. Thirty-five eligible studies were included. Using meta-analysis of proportions, the overall seroprevalence of anti-SARS-CoV-2 antibodies was calculated as 16% (95% CI 13.1-18.9%). Based on antibody isotypes, 14.6% (95% CI 12.2-17.1%) and 11.5% (95% CI 8.7-14.2%) were seropositive for SARS-CoV-2 IgG and IgM, respectively, while 6.6% (95% CI 4.9-8.3%) were tested positive for both IgM and IgG. Healthcare workers (16.3%) had higher seroprevalence than the general population (11.7%), blood donors (7.5%) and pregnant women (5.7%). The finding of this systematic review and meta-analysis (SRMA) may not accurately reflect the true seroprevalence status of SARS-CoV-2 infection in Africa, hence, further seroprevalence studies across Africa are required to assess and monitor the growing COVID-19 burden.

Predictors of anti-SARS-CoV-2 seropositivity: An Egyptian population-based study

Background

Population-based studies on the determinants of COVID-19 seroprevalence constitute a cornerstone in guiding appropriate preventive measures. Such studies are scarce in Egypt, thus we conducted this study to explore risk factors for SARS-CoV-2 seropositivity.

Methods

This survey included 2919 participants from 10 Egyptian governorates. Sera were tested for SARS-CoV-2 spike (S) and nucleocapsid (N) antibodies. Univariate and multivariate analyses were performed to identify associated factors and predictors of seropositivity regarding sociodemographic factors, clinical data, and personal practices of participants. A subgroup analysis was performed to investigate the occupational risks of seropositivity.

Results

Seropositivity was recorded in 1564 participants (53.6%). Independent predictors of seropositivity included non-smokers (aOR = 1.817; 95% CI: 1.407-2.346, p = 0.000), having blood group A (aOR = 1.231; 95% CI: 1.016-1.493, p = 0.034), a history of COVID-19 infection (aOR = 2.997; 95% CI: 2.176-4.127, p = 0.000), COVID-19 vaccination (aOR = 4.349; 95%CI: 2.798-6.759, p = 0.000), higher crowding index (aOR = 1.229; 95% CI: 1.041-1.451, p = 0.015), anosmia and/or ageusia (aOR = 3.453; 95% CI: 2.661-4.481, p = 0.000) and history of fever (aOR = 1.269; 95% CI: 1.033-1.560, p = 0.023). Healthcare worker and Obesity/overweight were additional significant predictors of seropositivity among the working participants (aOR = 1.760; 95% CI: 1.301-2.381, p = 0.000 and aOR = 1.384; 95% CI: 1.059-1.808, p = 0.019, respectively). Additional factors showing association with seropositivity in the univariate analysis were: female gender, age group (15-39 years), higher educational level (preparatory and above), lack of environmental disinfection and having roommates at the workplace. There was a positive correlation between the titers of both antibodies. Age was weakly correlated with anti-S titer, while anti-N was significantly correlated with the number of protective measures applied by the participants. Both antibodies were significantly correlated with adult BMI, while both were significantly negatively correlated with the smoking index.

Conclusions

SARS-CoV-2 seropositivity was associated with some personal and behavioral and occupation-related factors. Fever and anosmia and/or ageusia were the symptoms mostly associated with seropositivity.

The COVID-19 pandemic in the African continent

In December 2019, a new coronavirus, severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) and associated disease, coronavirus disease 2019 (COVID-19), was identified in China. This virus spread quickly and in March, 2020, it was declared a pandemic. Scientists predicted the worst scenario to occur in Africa since it was the least developed of the continents in terms of human development index, lagged behind others in achievement of the United Nations sustainable development goals (SDGs), has inadequate resources for provision of social services, and has many fragile states. In addition, there were relatively few research reporting findings on COVID-19 in Africa. On the contrary, the more developed countries reported higher disease incidences and mortality rates. However, for Africa, the earlier predictions and modelling into COVID-19 incidence and mortality did not fit into the reality. Therefore, the main objective of this forum is to bring together infectious diseases and public health experts to give an overview of COVID-19 in Africa and share their thoughts and opinions on why Africa behaved the way it did. Furthermore, the experts highlight what needs to be done to support Africa to consolidate the status quo and overcome the negative effects of COVID-19 so as to accelerate attainment of the SDGs.

Assessment of Clinical Outcomes Among Children and Adolescents Hospitalized With COVID-19 in 6 Sub-Saharan African Countries

IMPORTANCE

Little is known about COVID-19 outcomes among children and adolescents in sub-Saharan Africa, where preexisting comorbidities are prevalent.

OBJECTIVE

To assess the clinical outcomes and factors associated with outcomes among children and adolescents hospitalized with COVID-19 in 6 countries in sub-Saharan Africa.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study was a retrospective record review of data from 25 hospitals in the Democratic Republic of the Congo, Ghana, Kenya, Nigeria, South Africa, and Uganda from March 1 to December 31, 2020, and included 469 hospitalized patients aged 0 to 19 years with SARS-CoV-2 infection.

EXPOSURES

Age, sex, preexisting comorbidities, and region of residence.

MAIN OUTCOMES AND MEASURES

An ordinal primary outcome scale was used comprising 5 categories: (1) hospitalization without oxygen supplementation, (2) hospitalization with oxygen supplementation, (3) ICU admission, (4) invasive mechanical ventilation, and (5) death. The secondary outcome was length of hospital stay.

RESULTS

Among 469 hospitalized children and adolescents, the median age was 5.9 years (IQR, 1.6-11.1 years); 245 patients (52.4%) were male, and 115 (24.5%) had comorbidities. A total of 39 patients (8.3%) were from central Africa, 172 (36.7%) from eastern Africa, 208 (44.3%) from southern Africa, and 50 (10.7%) from western Africa. Eighteen patients had suspected (n = 6) or confirmed (n = 12) multisystem inflammatory syndrome in children. Thirty-nine patients (8.3%) died, including 22 of 69 patients (31.9%) who required intensive care unit admission and 4 of 18 patients (22.2%) with suspected or confirmed multisystem inflammatory syndrome in children. Among 468 patients, 418 (89.3%) were discharged, and 16 (3.4%) remained hospitalized. The likelihood of outcomes with higher vs lower severity among children younger than 1 year expressed as adjusted odds ratio (aOR) was 4.89 (95% CI, 1.44-16.61) times higher than that of adolescents aged 15 to 19 years. The presence of hypertension (aOR, 5.91; 95% CI, 1.89-18.50), chronic lung disease (aOR, 2.97; 95% CI, 1.65-5.37), or a hematological disorder (aOR, 3.10; 95% CI, 1.04-9.24) was associated with severe outcomes. Age younger than 1 year (adjusted subdistribution hazard ratio [asHR], 0.48; 95% CI, 0.27-0.87), the presence of 1 comorbidity (asHR, 0.54; 95% CI, 0.40-0.72), and the presence of 2 or more comorbidities (asHR, 0.26; 95% CI, 0.18-0.38) were associated with reduced rates of hospital discharge.

CONCLUSIONS AND RELEVANCE

In this cohort study of children and adolescents hospitalized with COVID-19 in sub-Saharan Africa, high rates of morbidity and mortality were observed among infants and patients with noncommunicable disease comorbidities, suggesting that COVID-19 vaccination and therapeutic interventions are needed for young populations in this region.

SARS-CoV-2 IgG Seroprevalence among Blood Donors as a Monitor of the COVID-19 Epidemic, Brazil

During epidemics, data from different sources can provide information on varying aspects of the epidemic process. Serology-based epidemiologic surveys could be used to compose a consistent epidemic scenario. We assessed the seroprevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) IgG in serum samples collected from 7,837 blood donors in 7 cities of Brazil during March–December 2020. Based on our results, we propose a modification in a compartmental model that uses reported number of SARS-CoV-2 cases and serology results from blood donors as inputs and delivers estimates of hidden variables, such as daily values of SARS-CoV-2 transmission rates and cumulative incidence rate of reported and unreported SARS-CoV-2 cases. We concluded that the information about cumulative incidence of a disease in a city’s population can be obtained by testing serum samples collected from blood donors. Our proposed method also can be extended to surveillance of other infectious diseases.

High SARS-CoV-2 Seroprevalence among Healthcare Workers in Bamako, Mali

In Mali, a country in West Africa, cumulative confirmed COVID-19 cases and deaths among healthcare workers (HCWs) remain enigmatically low, despite a series of waves, circulation of SARS-CoV-2 variants, the country's weak healthcare system, and a general lack of adherence to public health mitigation measures. The goal of the study was to determine whether exposure is important by assessing the seroprevalence of anti-SARS-CoV-2 IgG antibodies in HCWs. The study was conducted between November 2020 and June 2021. HCWs in the major hospitals where COVID-19 cases were being cared for in the capital city, Bamako, Mali, were recruited. During the study period, vaccinations were not yet available. The ELISA of the IgG against the spike protein was optimized and quantitatively measured. A total of 240 HCWs were enrolled in the study, of which seropositivity was observed in 147 cases (61.8%). A continuous increase in the seropositivity was observed, over time, during the study period, from 50% at the beginning to 70% at the end of the study. HCWs who provided direct care to COVID-19 patients and were potentially highly exposed did not have the highest seropositivity rate. Vulnerable HCWs with comorbidities such as obesity, diabetes, and asthma had even higher seropositivity rates at 77.8%, 75.0%, and 66.7%, respectively. Overall, HCWs had high SARS-CoV-2 seroprevalence, likely reflecting a "herd" immunity level, which could be protective at some degrees. These data suggest that the low number of cases and deaths among HCWs in Mali is not due to a lack of occupational exposure to the virus but rather related to other factors that need to be investigated.

Variation in SARS-CoV-2 seroprevalence in children in the region of Asturias, Northern Spain

BACKGROUND

Updated seroprevalence estimates are important to describe the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) landscape and to guide public health decisions. The aims are to describe longitudinal changes in seroprevalence in children in a region in Northern Spain and to analyze factors associated with SARS-CoV-2 seropositivity.

METHODS

Prospective multicenter longitudinal study with subjects recruited from July to September 2020. Children (up to 14 years old) were included and followed up until September 2021. Venous blood samples were collected every six months during three testing rounds and were analyzed for SARS-CoV-2 antibodies. The data regarding epidemiological features, contact tracing, symptoms, and virological tests were collected. The evolution of SARS-CoV-2 seroprevalence during the study and the differences between children with positive and negative SARS-CoV-2 antibody tests were analyzed.

RESULTS

Two hundred children were recruited (50.5% girls, median age 9.7 years). The overall seroprevalence increased from round 1 [1.5%, 95% confidence interval (CI) 0.3%-4.3%] to round 2 (9.1%, 95% CI 4.6%-12.7%) and round 3 (16.6%, 95% CI 9.5%-19.6%) (P < 0.001). Main changes occurred in children aged zero to four years (P = 0.001) who lived in urban areas (P < 0.001). None of the children who were previously positive became seronegative. Following multivariable analysis, three variables independently associated with SARS-CoV-2 seropositivity were identified: close contact with coronavirus disease 2019 (COVID-19) confirmed or suspected cases [odds ratio (OR) = 3.9, 95% CI 1.2-12.5], previous positive virological test (OR = 17.1, 95% CI 3.7-78.3) and fatigue (OR = 18.1, 95% CI 1.7-193.4).

CONCLUSIONS

SARS-CoV-2 seroprevalence in children has remarkably increased during the time of our study. Fatigue was the only COVID-19-compatible symptom that was more frequent in seropositive than in seronegative children.

High infectious disease burden as a basis for the observed high frequency of asymptomatic SARS-CoV-2 infections in sub-Saharan Africa

Following the coronavirus outbreaks described as severe acute respiratory syndrome (SARS) in 2003 and the Middle East respiratory syndrome (MERS) in 2012, the world has again been challenged by yet another corona virus, named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). SARS-CoV-2 infections were first detected in a Chinese Province in December 2019 and then declared a pandemic by the World Health Organization in March 2020. An infection caused by SARS-CoV-2 may result in asymptomatic, uncomplicated or fatal coronavirus disease 2019 (COVID-19). Fatal disease has been linked with the uncontrolled "cytokine storm" manifesting with complications mostly in people with underlying cardiovascular and pulmonary disease conditions. The severity of COVID-19 disease and the associated mortality has been disproportionately lower in terms of number of cases and deaths in Africa and also Asia in comparison to Europe and North America. Also, persons of colour residing in Europe and North America have been identified as a highly susceptible population due to a combination of several socioeconomic factors and poor access to quality healthcare. Interestingly, this has not been the case in sub-Saharan Africa where majority of the population are even more deprived of the aforementioned factors. On the contrary, sub-Saharan Africa has recorded the lowest levels of mortality and morbidity associated with the disease, and an overwhelming proportion of infections are asymptomatic. Whilst it can be argued that these lower number of cases in Africa may be due to challenges associated with the diagnosis of the disease such as lack of trained personnel and infrastructure, the number of persons who get infected and develop symptoms is proportionally lower than those who are asymptomatic, including asymptomatic cases that are never diagnosed. This review discusses the most probable reasons for the significantly fewer cases of severe COVID-19 disease and deaths in sub-Saharan Africa.