Consideration for the asymptomatic transmission of COVID-19: Systematic Review and Meta-Analysis

  1. Khaiwal Ravindra
  2. Vivek Singh Malik
  3. Bijaya K Padhi
  4. Sonu Goel
  5. Madhu Gupta

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Abstract

Objective

Worldwide countries are experiencing viral load in their population, leading to potential infectivity of asymptomatic COVID-19. Current systematic review and meta-analysis aimed to investigate the role of asymptomatic infection worldwide reported in family-cluster, adults, children, health care workers, and travelers.

Design

Online literature search (PubMed, Google Scholar, medRixv, and BioRixv) was accomplished using standard Boolean operators, studies published till 07 th June 2020.

Setting

Studies were included from case reports, short communication, and retrospective to cover sufficient asymptomatic COVID-19 transmission reported.

Participants

Familial-clusters, adults, children, health care workers, and travelers.

Results

We observed asymptomatic transmission among familial-cluster, adults, children, health care workers, and travelers with a proportion of 32% 37%, 26%, 6%, and 32%, respectively. This study observed an overall proportion of 31% (95%CI: 0.19-0.44) with heterogeneity of I 2 (97.28%, p=<0.001) among all asymptomatic populations mentioned in this study. Among children and healthcare workers, this study showed no heterogeneity; to overcome the interpretation from a fixed model, the random effect model was also applied to estimate the average distribution across studies included in the meta-analysis.

Conclusion

We found and suggest the rigorous epidemiological history, early isolation, social distancing, and increased quarantine period (at least 28 days) after screening asymptomatic cases as well as their close contacts for chest CT scan even after their negative nucleic acid testing to minimize the spread among the community. This systematic review and meta-analysis support asymptomatic COVID-19 transmission between person to person depending on the variation of virus incubation period among individuals. Children especially, school-going aged <18 years, need to be monitored and prevention strategy, e.g., chest CT and social distancing required to prevent the community transmission of COVID-19 in asymptomatic mode.

Strengths and limitations of this study

  • Examine the possibility of asymptomatic COVID-19 transmission in the community at different levels.

  • Supports contact tracing, social distancing, early isolation, and increased quarantine period to minimize the risk of virus spread.

  • Supports chest CT scan and viral nucleic acid testing to identify the asymptomatic cases in the community.

  • Supports rigorous epidemiological history with multiple detection methods.

  • A higher proportion of asymptomatic incidence was seen, suggests monitoring, and maintaining social distancing.

Article activity feed

  1. ScreenIT

    SciScore for 10.1101/2020.10.06.20207597: (What is this?)

    Please note, not all rigor criteria are appropriate for all manuscripts.

    Table 1: Rigor

    Institutional Review Board Statementnot detected.
    Randomizationnot detected.
    Blindingnot detected.
    Power Analysisnot detected.
    Sex as a biological variablenot detected.

    Table 2: Resources

    Software and Algorithms
    SentencesResources
    AND (asymptomatic transmission)”, “(Wuhan flu) AND (asymptomatic transmission)”, “(2019-nCoV acute respiratory disease) AND (asymptomatic transmission)”, “(2019-nCoV respiratory syndrome) AND (asymptomatic transmission)” used for the PubMed database, Google scholar, medRxiv, and BioRixv.
    PubMed
    suggested: (PubMed, RRID:SCR_004846)
    Google scholar
    suggested: (Google Scholar, RRID:SCR_008878)

    Results from OddPub: We did not detect open data. We also did not detect open code. Researchers are encouraged to share open data when possible (see Nature blog).

    Results from LimitationRecognizer: We detected the following sentences addressing limitations in the study:
    Limitations: There are some limitations in the current systematic review and meta-analysis. A mixed population, a continuous variable, variation in clinical conditions, and statistical methods may differ and cause heterogeneity among studies included in the current meta-analysis. Further, the study included only asymptomatic COVID-19 transmission reported cases that were included. Study Importance: This is the first study reviewing the possibility of asymptomatic COVID-19 transmission at different levels in the community and identified the potential role of isolation, identification of close contacts, social distancing and testing asymptomatic COVID-19 cases with chest CT scan and nucleic acid testing to minimize the spread of the virus in the community. The implication of our study: This is the first meta-analysis on the possibility of asymptomatic COVID-19 transmission covering different levels in the community.

    Results from TrialIdentifier: No clinical trial numbers were referenced.

    Results from Barzooka: We did not find any issues relating to the usage of bar graphs.

    Results from JetFighter: We did not find any issues relating to colormaps.

    Results from rtransparent:
    • Thank you for including a conflict of interest statement. Authors are encouraged to include this statement when submitting to a journal.
    • Thank you for including a funding statement. Authors are encouraged to include this statement when submitting to a journal.
    • No protocol registration statement was detected.

    About SciScore

    SciScore is an automated tool that is designed to assist expert reviewers by finding and presenting formulaic information scattered throughout a paper in a standard, easy to digest format. SciScore checks for the presence and correctness of RRIDs (research resource identifiers), and for rigor criteria such as sex and investigator blinding. For details on the theoretical underpinning of rigor criteria and the tools shown here, including references cited, please follow this link.

  2. Version published to 10.1101/2020.10.06.20207597 on medRxiv