ArticleThe Lancet. Infectious diseases2020
Connecting clusters of COVID-19: an epidemiological and serological investigation.
Article in The Lancet. Infectious diseases, 2020. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 149 papers, 3 of them syntheses that pooled it.
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Who cites it
149 citing papers in PubMed, 3 syntheses or guidelines pooled it, 294 citations in OpenAlex.
- Comparative effectiveness of contact tracing interventions in the context of the COVID-19 pandemic: a systematic review.European journal of epidemiology · 2023Pooled it
- Diagnostic performance of COVID-19 serological assays during early infection: A systematic review and meta-analysis of 11 516 samples.Influenza and other respiratory viruses · 2021Pooled it
- Landscape of epitopes targeted by T cells in 852 individuals recovered from COVID-19: Meta-analysis, immunoprevalence, and web platform.Cell reports. Medicine · 2021Pooled it
- Immune response dynamics in COVID-19 patients to SARS-CoV-2 and other human coronaviruses.PloS one · 2021Trial
- Acute SARS-CoV-2 infection.Nature reviews. Disease primers · 2025Review
- Comparative evaluation of in-house ELISA and two commercial serological assays for the detection of antibodies against SARS-CoV-2.Scientific reports · 2025Article
- Urban Churches Show an Increase in Attendance, Donations, and Finances During the COVID-19 Pandemic in the USA: Evidence from the United Methodist Church.Journal of religion and health · 2024Article
- IgG and IgM differentiation in a particle-based agglutination assay by control over antigen surface density.APL bioengineering · 2024Article
- Genomic Analysis and Tracking of SARS-CoV-2 Variants in Gwangju, South Korea, From 2020 to 2022.Influenza and other respiratory viruses · 2024Article
- The serological IgG and neutralizing antibody of SARS-CoV-2 omicron variant reinfection in Jiangsu Province, China.Frontiers in public health · 2024Article
- A Systematic Review and Meta-Analysis Comparing the Diagnostic Accuracy Tests of COVID-19.Diagnostics (Basel, Switzerland) · 2023Review
- Real-time updating of dynamic social networks for COVID-19 vaccination strategies.Journal of ambient intelligence and humanized computing · 2023Article
- Emerging Landscape of SARS-CoV-2 Variants and Detection Technologies.Molecular diagnosis & therapy · 2023Review
- Application of microfluidic technologies on COVID-19 diagnosis and drug discovery.Acta pharmaceutica Sinica. B · 2023Review
- Evaluating Data Sharing of SARS-CoV-2 Genomes for Molecular Epidemiology across the COVID-19 Pandemic.Viruses · 2023Article
- Functional studies of HLA and its role in SARS-CoV-2: Stimulating T cell response and vaccine development.Life sciences · 2023Review
- Super-spreading social events for COVID-19 transmission: evidence from the investigation of six early clusters in Bahrain.Frontiers in public health · 2023Article
- The unintended consequences of inconsistent closure policies and mobility restrictions during epidemics.BMC global and public health · 2023Article
- Respective roles of social deprivation, health literacy, and clinical factors for COVID-19: a case-control study in hospitalized patients.Frontiers in public health · 2023Article
- Host transcriptional responses in nasal swabs identify potential SARS-CoV-2 infection in PCR negative patients.iScience · 2022Article
89 more citing papers are in PubMed but not listed here.
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Authors and funding
20 authors at 4 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundElucidation of the chain of disease transmission and identification of the source of coronavirus disease 2019 (COVID-19) infections are crucial for effective disease containment. We describe an epidemiological investigation that, with use of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) serological assays, established links between three clusters of COVID-19.
methodsIn Singapore, active case-finding and contact tracing were undertaken for all COVID-19 cases. Diagnosis for acute disease was confirmed with RT-PCR testing. When epidemiological information suggested that people might have been nodes of disease transmission but had recovered from illness, SARS-CoV-2 IgG serology testing was used to establish past infection.
findingsThree clusters of COVID-19, comprising 28 locally transmitted cases, were identified in Singapore; these clusters were from two churches (Church A and Church B) and a family gathering. The clusters in Church A and Church B were linked by an individual from Church A (A2), who transmitted SARS-CoV-2 infection to the primary case from Church B (F1) at a family gathering they both attended on Jan 25, 2020. All cases were confirmed by RT-PCR testing because they had active disease, except for A2, who at the time of testing had recovered from their illness and tested negative. This individual was eventually diagnosed with past infection by serological testing. ELISA assays showed an optical density of more than 1·4 for SARS-CoV-2 nucleoprotein and receptor binding domain antigens in titres up to 1/400, and viral neutralisation was noted in titres up to 1/320.
interpretationDevelopment and application of a serological assay has helped to establish connections between COVID-19 clusters in Singapore. Serological testing can have a crucial role in identifying convalescent cases or people with milder disease who might have been missed by other surveillance methods.
fundingNational Research Foundation (Singapore), National Natural Science Foundation (China), and National Medical Research Council (Singapore).
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