ArticleBMC medicine2021
SARS-CoV-2 exposure in Malawian blood donors: an analysis of seroprevalence and variant dynamics between January 2020 and July 2021.
Article in BMC medicine, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 38 papers, 1 of them a synthesis that pooled it.
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Who cites it
38 citing papers in PubMed, 1 synthesis or guideline pooled 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
- Trial-of-antibiotics to assist tuberculosis diagnosis in symptomatic adults in Malawi (ACT-TB study): a randomised controlled trial.The Lancet. Global health · 2023Trial
- Observational
- Evaluation of the diagnostic performance of iChroma serological test in high SARS-CoV-2 seroprevalence setting in Gabon.BMC infectious diseases · 2026Article
- SARS-CoV-2 neutralising antibody profiles reveal variant specific antibody dynamics and regional differences in infection histories in Malawi.PLOS global public health · 2026Article
- Characterising protective immune responses to SARS-CoV-2 in urban and rural Malawi between February 2021 and April 2022.Scientific reports · 2025Article
- Severe Acute Respiratory Syndrome Coronavirus 2 Seroprevalence and Coronavirus Disease 2019 Vaccination Trends: Findings from Surveillance Conducted at First Antenatal Care Visits in Kenya, Nigeria, Malawi, Mozambique, Uganda, and Zambia, 2021-2022.The American journal of tropical medicine and hygiene · 2025Article
- Rethinking the evidence on COVID-19 in Africa.The Lancet. Infectious diseases · 2025Review
- Population-based cross-sectional seroprevalence study of SARS-CoV-2 infection in urban residential areas in Ghana.BMJ public health · 2025Article
- Mortality risk information and health-seeking behavior during an epidemic.Proceedings of the National Academy of Sciences of the United States of America · 2024Article
- SARS-CoV-2 Seroprevalence and Vaccine Uptake among Pregnant Women at First Antenatal Care Visits in Malawi.The American journal of tropical medicine and hygiene · 2024Article
- Prevalence of Endemic Respiratory Viruses During the COVID-19 Pandemic in Urban and Rural Malawi.Open forum infectious diseases · 2024Article
- "Kuteteza": A community-engaged COVID-19 Prevention and Protection Initiative in Southern Malawi.Wellcome open research · 2024Article
- SARS-CoV-2 seroepidemiology in Cape Town, South Africa, and implications for future outbreaks in low-income communities.PLOS global public health · 2024Article
- Characterizing the evolving SARS-CoV-2 seroprevalence in urban and rural Malawi between February 2021 and April 2022: A population-based cohort study.International journal of infectious diseases : IJID : official publication of the International Society for Infectious Diseases · 2023Article
- Utilizing river and wastewater as a SARS-CoV-2 surveillance tool in settings with limited formal sewage systems.Nature communications · 2023Article
- Effects of COVID-19 on Maternal and Neonatal Outcomes and Access to Antenatal and Postnatal Care, Malawi.Emerging infectious diseases · 2023Article
- SARS-CoV-2 seroprevalence among blood donors in Uganda: 2019-2022.Transfusion · 2023Article
- Using mortuary and burial data to place COVID-19 in Lusaka, Zambia within a global context.Nature communications · 2023Article
- The evolution of SARS-CoV-2.Nature reviews. Microbiology · 2023Review
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Authors and funding
23 authors.
Funding
Abstract
backgroundBy August 2021, the COVID-19 pandemic has been less severe in sub-Saharan Africa than elsewhere. In Malawi, there have been three subsequent epidemic waves. We therefore aimed to describe the dynamics of SARS-CoV-2 exposure in Malawi.
methodsWe measured the seroprevalence of anti-SARS-CoV-2 antibodies amongst randomly selected blood transfusion donor sera in Malawi from January 2020 to July 2021 using a cross-sectional study design. In a subset, we also assessed in vitro neutralisation against the original variant (D614G WT) and the Beta variant.
resultsA total of 5085 samples were selected from the blood donor database, of which 4075 (80.1%) were aged 20-49 years. Of the total, 1401 were seropositive. After adjustment for assay characteristics and applying population weights, seropositivity reached peaks in October 2020 (18.5%) and May 2021 (64.9%) reflecting the first two epidemic waves. Unlike the first wave, both urban and rural areas had high seropositivity in the second wave, Balaka (rural, 66.2%, April 2021), Blantyre (urban, 75.6%, May 2021), Lilongwe (urban, 78.0%, May 2021), and Mzuzu (urban, 74.6%, April 2021). Blantyre and Mzuzu also show indications of the start of a third pandemic wave with seroprevalence picking up again in July 2021 (Blantyre, 81.7%; Mzuzu, 71.0%). More first wave sera showed in vitro neutralisation activity against the original variant (78% [7/9]) than the beta variant (22% [2/9]), while more second wave sera showed neutralisation activity against the beta variant (75% [12/16]) than the original variant (63% [10/16]).
conclusionThe findings confirm extensive SARS-CoV-2 exposure in Malawi over two epidemic waves with likely poor cross-protection to reinfection from the first on the second wave. The dynamics of SARS-CoV-2 exposure will therefore need to be taken into account in the formulation of the COVID-19 vaccination policy in Malawi and across the region. Future studies should use an adequate sample size for the assessment of neutralisation activity across a panel of SARS-CoV-2 variants of concern/interest to estimate community immunity.
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