ArticleBMJ global health2021
SARS-CoV-2 antibody prevalence in Sierra Leone, March 2021: a cross-sectional, nationally representative, age-stratified serosurvey.
Article in BMJ global health, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 33 papers, 3 of them syntheses that pooled it.
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33 citing papers in PubMed, 3 syntheses or guidelines pooled it.
- Estimating Hidden Population Size of COVID-19 using Respondent-Driven Sampling Method - A Systematic Review.Infectious disorders drug targets · 2024Pooled it
- Global SARS-CoV-2 seroprevalence from January 2020 to April 2022: A systematic review and meta-analysis of standardized population-based studies.PLoS medicine · 2022Pooled it
- SARS-CoV-2 infection in Africa: a systematic review and meta-analysis of standardised seroprevalence studies, from January 2020 to December 2021.BMJ global health · 2022Pooled it
- Informing life-course immunization and pandemic preparedness: a COVID-19 vaccine evaluation and HPV introduction experience in Sierra Leone.BMC public health · 2026Article
- Evaluation of the diagnostic performance of iChroma serological test in high SARS-CoV-2 seroprevalence setting in Gabon.BMC infectious diseases · 2026Article
- Distribution and determinants of COVID-19 seroprevalence in a hard-to-access health district in Mali.PLOS global public health · 2025Article
- Psychological distress and coping mechanisms due to the COVID-19 pandemic among the adult population in Bo Sierra Leone. A cross-sectional study.PLOS mental health · 2025Article
- Population-based cross-sectional seroprevalence study of SARS-CoV-2 infection in urban residential areas in Ghana.BMJ public health · 2025Article
- Post-Omicron SARS-CoV-2 antibody prevalence in Sierra Leone: A cross-sectional, nationally representative, follow-up serosurvey.PLOS global public health · 2025Article
- SARS-CoV-2 seroprevalence and associated factors among people living with HIV in Sierra Leone.Immunity, inflammation and disease · 2024Article
- Article
- SARS-CoV-2 seroepidemiology in Cape Town, South Africa, and implications for future outbreaks in low-income communities.PLOS global public health · 2024Article
- High SARS-CoV-2 seroincidence but low excess COVID mortality in Sierra Leone in 2020-2022.PLOS global public health · 2024Article
- COVID-19 in 16 West African Countries: An Assessment of the Epidemiology and Genetic Diversity of SARS-CoV-2 after Four Epidemic Waves.The American journal of tropical medicine and hygiene · 2023Review
- Attributed causes of excess mortality during the COVID-19 pandemic in a south Indian city.Nature communications · 2023Article
- All-cause mortality of hospitalised patients with suspected COVID-19 in Sierra Leone: a prospective cohort study.BMJ open · 2023Article
- Trajectories of Seroprevalence and Neutralizing Activity of Antibodies against SARS-CoV-2 in Southern Switzerland between July 2020 and July 2021: An Ongoing, Prospective Population-Based Cohort Study.International journal of environmental research and public health · 2023Article
- High Severe Acute Respiratory Syndrome Coronavirus 2 Antibody Prevalence After the Third Epidemic Wave (May-October 2021) in Matadi, Democratic Republic of the Congo.Open forum infectious diseases · 2023Article
- High SARS-CoV-2 Seroprevalence after Second COVID-19 Wave (October 2020-April 2021), Democratic Republic of the Congo.Emerging infectious diseases · 2023Article
- Seroprevalence of anti-SARS-CoV-2 IgG antibodies in HIV-positive and HIV-negative patients in clinical settings in Douala, Cameroon.Frontiers in epidemiology · 2023Article
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Abstract
introductionAs of 26 March 2021, the Africa Centres for Disease Control and Prevention had reported 4 159 055 cases of COVID-19 and 111 357 deaths among the 55 African Union member states; however, no country has published a nationally representative serosurvey as of October 2021. Such data are vital for understanding the pandemic's progression on the continent, evaluating containment measures, and policy planning.
methodsWe conducted a cross-sectional, nationally representative, age-stratified serosurvey in Sierra Leone in March 2021 by randomly selecting 120 Enumeration Areas throughout the country and 10 randomly selected households in each of these. One to two persons per selected household were interviewed to collect information on sociodemographics, symptoms suggestive of COVID-19, exposure history to laboratory-confirmed COVID-19 cases, and history of COVID-19 illness. Capillary blood was collected by fingerstick, and blood samples were tested using the Hangzhou Biotest Biotech RightSign COVID-19 IgG/IgM Rapid Test Cassette. Total seroprevalence was estimated after applying sampling weights.
resultsThe overall weighted seroprevalence was 2.6% (95% CI 1.9% to 3.4%). This was 43 times higher than the reported number of cases. Rural seropositivity was 1.8% (95% CI 1.0% to 2.5%), and urban seropositivity was 4.2% (95% CI 2.6% to 5.7%). DISCUSSION: Overall seroprevalence was low compared with countries in Europe and the Americas (suggesting relatively successful containment in Sierra Leone). This has ramifications for the country's third wave (which started in June 2021), during which the average number of daily reported cases was 87 by the end of the month:this could potentially be on the order of 3700 actual infections per day, calling for stronger containment measures in a country with only 0.2% of people fully vaccinated. It may also reflect significant under-reporting of incidence and mortality across the continent.
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