SynthesisPloS one2021
Magnitude of asymptomatic COVID-19 cases throughout the course of infection: A systematic review and meta-analysis.
Synthesis in PloS one, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 89 papers, 5 of them syntheses that pooled it.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
89 citing papers in PubMed, 5 syntheses or guidelines pooled it, 194 citations in OpenAlex.
- Estimating Hidden Population Size of COVID-19 using Respondent-Driven Sampling Method - A Systematic Review.Infectious disorders drug targets · 2024Pooled it
- Meta-analysis of COVID-19 prevalence during preoperative COVID-19 screening in asymptomatic patients.BMJ open · 2022Pooled it
- Long distance airborne transmission of SARS-CoV-2: rapid systematic review.BMJ (Clinical research ed.) · 2022Pooled it
- Prevalence of Coronavirus Disease 2019 (COVID-19) in Different Clinical Stages before the National COVID-19 Vaccination Programme in Malaysia: A Systematic Review and Meta-Analysis.International journal of environmental research and public health · 2022Pooled it
- Recommendations for Safe Dental Care: A Systematic Review of Clinical Practice Guidelines in the First Year of the COVID-19 Pandemic.International journal of environmental research and public health · 2021Pooled it
- Early treatment of Favipiravir in COVID-19 patients without pneumonia: a multicentre, open-labelled, randomized control study.Emerging microbes & infections · 2022Trial
- Multi-event dynamic capture-recapture model for big data: Estimating undetected COVID-19 cases in British Columbia, Canada.Infectious Disease Modelling · 2026Article
- Wastewater-based reproduction rates for epidemic curve reconstruction.Biostatistics (Oxford, England) · 2025Article
- SARS-CoV-2 mRNA Vaccine Effectiveness in the Borriana COVID-19 Cohort: A Prospective Population-Based Cohort Study.Epidemiologia (Basel, Switzerland) · 2025Article
- Estimation of undetected asymptomatic infections of COVID-19: a mathematical modeling approach.Scientific reports · 2025Article
- Genetic Susceptibility to Tuberculosis and the Utility of Polygenic Scores in Population Stratification.International journal of molecular sciences · 2025Review
- The burden of COVID-19 in primary care of Almaty, Kazakhstan, 2021-2022.Scientific reports · 2025Article
- Incidence of Fetal Arrhythmia Before and During the COVID-19 Pandemic: A Single-Center Experience.Pediatric cardiology · 2025Article
- Assessment of the Effective Sensitivity of SARS-CoV-2 Sample Pooling Based on a Large-Scale Screening Experience: Retrospective Analysis.JMIR public health and surveillance · 2024Article
- Underreporting of Cases in the COVID-19 Outbreak of Borriana (Spain) during Mass Gathering Events in March 2020: A Cross-Sectional Study.Epidemiologia (Basel, Switzerland) · 2024Article
- Estimating population infection rates from non-random testing data: Evidence from the COVID-19 pandemic.PloS one · 2024Article
- Tracking inflammation resolution signatures in lungs after SARS-CoV-2 omicron BA.1 infection of K18-hACE2 mice.PloS one · 2024Article
- PCR testing of traced contacts for SARS-CoV-2 in England, January to July 2021.Euro surveillance : bulletin Europeen sur les maladies transmissibles = European communicable disease bulletin · 2023Article
- Seroprevalence trends of anti-SARS-CoV-2 antibodies and associated risk factors: a population-based study.Infection · 2023Article
- Asymptomatic severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection in adults is uncommon using rigorous symptom characterization and follow-up in an acute-care adult hospital outbreak.Infection control and hospital epidemiology · 2023Article
29 more citing papers are in PubMed but not listed here.
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
7 authors at 2 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundAsymptomatic SARS-CoV-2 infections are responsible for potentially significant transmission of COVID-19. Worldwide, a number of studies were conducted to estimate the magnitude of asymptomatic COVID-19 cases. However, there is a need for more robust and well-designed studies to have a relevant public health intervention. Synthesis of the available studies significantly strengthens the quality of evidences for public health practice. Thus, this systematic review and meta-analysis aimed to determine the overall magnitude of asymptomatic COVID-19 cases throughout the course of infection using available evidences.
methodsWe followed the PRISMA checklist to present this study. Two experienced review authors (MA and DBK) were systematically searched international electronic databases for studies. We performed meta-analysis using R statistical software. The overall weighted proportion of asymptomatic COVID-19 cases throughout the course infection was computed. The pooled estimates with 95% confidence intervals were presented using forest plot. Egger's tests were used to assess publication bias, and primary estimates were pooled using a random effects model. Furthermore, a sensitivity analysis was conducted to assure the robustness of the result.
resultsA total of 28 studies that satisfied the eligibility criteria were included in this systematic review and meta-analysis. Consequently, in the meta-analysis, a total of 6,071 COVID-19 cases were included. The proportion of asymptomatic infections among the included studies ranged from 1.4% to 78.3%. The findings of this meta-analysis showed that the weighted pooled proportion of asymptomatic COVID-19 cases throughout the course of infection was 25% (95%CI: 16-38). The leave-one out result also revealed that the weighted pooled average of asymptomatic SARS-CoV-2 infection was between 28% and 31.4%.
conclusionsIn conclusion, one-fourth of SARS-CoV-2 infections are remained asymptomatic throughout the course infection. Scale-up of testing, which targeting high risk populations is recommended to tackle the pandemic.
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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.