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Secondary Transmission of Coronavirus Disease from Presymptomatic Persons, China

Weiwei Zhang, Weibin Cheng, Lei Luo

    Emerging Infectious Diseases
    |May 27, 2020
    PubMed

    Insights

    Close contacts living with or frequently interacting with individuals presymptomatic for coronavirus disease (COVID-19) faced a higher infection risk. This study confirms transmission potential from presymptomatic COVID-19 cases.

    Area of Science:

    • Epidemiology
    • Infectious Diseases
    • Public Health

    Background:

    • Understanding transmission dynamics of novel viruses is crucial for effective public health interventions.
    • Presymptomatic transmission of coronavirus disease (COVID-19) has been a significant concern for disease control.

    Purpose of the Study:

    • To investigate the secondary attack rate associated with different contact types involving presymptomatic individuals with COVID-19.
    • To provide population-based evidence on the risk of COVID-19 transmission from presymptomatic cases.

    Main Methods:

    • Population-based study design.
    • Analysis of secondary attack rates based on varying degrees of contact with index COVID-19 cases.
    • Assessment of transmission risk from presymptomatic individuals.

    Main Results:

    • Close contacts, particularly those sharing a household or having frequent interactions with an index case-patient, exhibited a significantly higher risk of contracting COVID-19.
    • Evidence supports the role of presymptomatic individuals in the transmission of COVID-19 within the population.

    Conclusions:

    • Living with or having frequent contact with a COVID-19 case during their presymptomatic phase increases the risk of infection.
    • Findings underscore the importance of considering presymptomatic transmission in strategies to control the spread of COVID-19.

    Keywords:
    2019 novel coronavirus diseaseCOVID-19ChinaSARSSARS-CoV-2coronavirus diseasecoronavirus secondary transmissionpresymptomaticrespiratory infectionssecondary attack ratesevere acute respiratory syndrome coronavirus 2viruseszoonoses

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