SynthesisClinical microbiology and infection : the official publication of the European Society of Clinical Microbiology and Infectious Diseases2022
Transmission of Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) from pre and asymptomatic infected individuals: a systematic review.
Synthesis in Clinical microbiology and infection : the official publication of the European Society of Clinical Microbiology and Infectious Diseases, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 23 papers, 6 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
23 citing papers in PubMed, 6 syntheses or guidelines pooled it.
- Serial cycle threshold to assess the infectious potential of SARS-CoV-2: A systematic review.Epidemiology and infection · 2026Pooled it
- Viral cultures for assessing airborne infectiousness of SARS-CoV-2: a systematic review and meta-analysis.BMC infectious diseases · 2025Pooled it
- Impact of disease severity, age, sex, comorbidity, and vaccination on secondary attack rates of SARS-CoV-2: a global systematic review and meta-analysis.BMC infectious diseases · 2025Pooled it
- The effectiveness of interventions to reduce the transmission of acute respiratory infections in care homes: a systematic review.Journal of public health (Oxford, England) · 2024Pooled it
- Viral cultures, cycle threshold values and viral load estimation for assessing SARS-CoV-2 infectiousness in haematopoietic stem cell and solid organ transplant patients: a systematic review.The Journal of hospital infection · 2023Pooled it
- How are countries responding differently to COVID-19: a systematic review of guidelines on isolation measures.Frontiers in public health · 2023Pooled it
- Efficacy and Safety of Ensitrelvir for Asymptomatic or Mild COVID-19: An Exploratory Analysis of a Multicenter, Randomized, Phase 2b/3 Clinical Trial.Influenza and other respiratory viruses · 2024Trial
- Age-Related Asymptomatic Rhinovirus Infections Contribute to the Sustained Prevalence in Adults and Are Not Mitigated by Nonpharmaceutical Interventions.Influenza and other respiratory viruses · 2026Article
- Occupational exposure monitoring of airborne respiratory viruses in outpatient medical clinics.Aerosol science and technology : the journal of the American Association for Aerosol Research · 2024Article
- Development and Evaluation of an In-House Real-Time RT-PCR Targeting nsp10 Gene for SARS-CoV-2 Detection.International journal of molecular sciences · 2024Article
- A Retrospective Analysis of Jordan's National COVID-19 Call Center: Operations, Effectiveness, and Lessons Learned.Journal of multidisciplinary healthcare · 2024Article
- DNA amplification tests at universal pre-admission screening with enhanced precaution strategies for asymptomatic patients with COVID-19.IJID regions · 2023Article
- Outcomes of a Community Engagement and Information Gathering Program to Support Telephone-Based COVID-19 Contact Tracing: Descriptive Analysis.JMIR public health and surveillance · 2022Article
- Lower transmissibility of SARS-CoV-2 among asymptomatic cases: evidence from contact tracing data in Oslo, Norway.BMC medicine · 2022Article
- Transmission of SARS-CoV-2 Associated with Cruise Ship Travel: A Systematic Review.Tropical medicine and infectious disease · 2022Review
- Detection of SARS-CoV-2 in exhaled air using non-invasive embedded strips in masks.American journal of infection control · 2022Article
- Presymptomatic, asymptomatic and post-symptomatic transmission of SARS-CoV-2: joint British Infection Association (BIA), Healthcare Infection Society (HIS), Infection Prevention Society (IPS) and Royal College of Pathologists (RCPath) guidance.BMC infectious diseases · 2022Article
- Contact tracing period and epidemiological characteristics of an outbreak of the SARS-CoV-2 Delta variant in Guangzhou.International journal of infectious diseases : IJID : official publication of the International Society for Infectious Diseases · 2022Article
- Virucidal efficacy of laundry sanitizers against SARS-CoV-2 and other coronaviruses and influenza viruses.Scientific reports · 2022Article
- Post-Vaccination SARS-CoV-2 Infections among Health Workers at the University Hospital of Verona, Italy: A Retrospective Cohort Survey.Vaccines · 2022Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
9 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundThe role of SARS-Cov-2-infected persons who develop symptoms after testing (presymptomatics) or not at all (asymptomatics) in the pandemic spread is unknown.
objectivesTo determine infectiousness and probable contribution of asymptomatic persons (at the time of testing) to pandemic SARS-CoV-2 spread. DATA SOURCES: LitCovid, medRxiv, Google Scholar, and WHO Covid-19 databases (to 31 March 2021) and references in included studies. STUDY ELIGIBILITY CRITERIA: Studies with a proven or hypothesized transmission chain based either on serial PCR cycle threshold readings and/or viral culture and/or gene sequencing, with adequate follow-up.
participantsPeople exposed to SARS-CoV-2 within 2-14 days to index asymptomatic (at time of observation) infected individuals.
interventionsReliability of symptom and signs was assessed within contemporary knowledge; transmission likelihood was assessed using adapted causality criteria.
methodsSystematic review. We contacted all included studies' corresponding authors requesting further details.
resultsWe included 18 studies from a diverse setting with substantial methodological variation (this field lacks standardized methodology). At initial testing, prevalence of asymptomatic cases was 12.5-100%. Of these, 6-100% were later determined to be presymptomatic, this proportion varying according to setting, methods of case ascertainment and population. Nursing/care home facilities reported high rates of presymptomatic: 50-100% (n = 3 studies). Fourteen studies were classified as high risk of, and four studies as at moderate risk of symptom ascertainment bias. High-risk studies may be less likely to distinguish between presymptomatic and asymptomatic cases. Six asymptomatic studies and four presymptomatic studies reported culturing infectious virus; data were too sparse to determine infectiousness duration. Three studies provided evidence of possible and three of probable/likely asymptomatic transmission; five studies provided possible and two probable/likely presymptomatic SARS-CoV-2 transmission.
conclusionHigh-quality studies provide probable evidence of SARS-CoV-2 transmission from presymptomatic and asymptomatic individuals, with highly variable estimated transmission rates.
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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.