Viral load and contact heterogeneity predict SARS-CoV-2 transmission and super-spreading events

  1. Ashish Goyal
  2. Daniel B Reeves
  3. E Fabian Cardozo-Ojeda
  4. Joshua T Schiffer  Is a corresponding author
  5. Bryan T Mayer
  1. Fred Hutchinson Cancer Research Center, United States

Abstract

SARS-CoV-2 is difficult to contain because many transmissions occur during pre-symptomatic infection. Unlike influenza, most SARS-CoV-2 infected people do not transmit while a small percentage infect large numbers of people. We designed mathematical models which link observed viral loads with epidemiologic features of each virus, including distribution of transmissions attributed to each infected person and duration between symptom onset in the transmitter and secondarily infected person. We identify that people infected with SARS-CoV-2 or influenza can be highly contagious for less than one day, congruent with peak viral load. SARS-CoV-2 super-spreader events occur when an infected person is shedding at a very high viral load and has a high number of exposed contacts. The higher predisposition of SARS-CoV-2 towards super-spreading events cannot be attributed to additional weeks of shedding relative to influenza. Rather, a person infected with SARS-CoV-2 exposes more people within equivalent physical contact networks, likely due to aerosolization.

Data availability

The original data and code is shared at: https://github.com/ashish2goyal/SARS_CoV_2_Super_Spreader_Event

Article and author information

Author details

  1. Ashish Goyal

    Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, United States
    Competing interests
    No competing interests declared.
  2. Daniel B Reeves

    Vaccine and Infectious Diseases, Fred Hutchinson Cancer Research Center, Seattle, United States
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-5684-9538
  3. E Fabian Cardozo-Ojeda

    Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, United States
    Competing interests
    No competing interests declared.
  4. Joshua T Schiffer

    Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, United States
    For correspondence
    jschiffe@fredhutch.org
    Competing interests
    Joshua T Schiffer, Reviewing editor, eLifeIs on the trial planning committee for a Gilead funded trial of remdesivir but is not reimbursed for this activity.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-2598-1621
  5. Bryan T Mayer

    Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, United States
    Competing interests
    No competing interests declared.

Funding

National Institute of Allergy and Infectious Diseases (R01 AI121129-05S1)

  • Joshua T Schiffer

Council of State and Territorial Epidemiologists (Inform Public Health Decision Making Funding Opportunity)

  • Joshua T Schiffer

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Copyright

© 2021, Goyal et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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  1. Ashish Goyal
  2. Daniel B Reeves
  3. E Fabian Cardozo-Ojeda
  4. Joshua T Schiffer
  5. Bryan T Mayer
(2021)
Viral load and contact heterogeneity predict SARS-CoV-2 transmission and super-spreading events
eLife 10:e63537.
https://doi.org/10.7554/eLife.63537

Share this article

https://doi.org/10.7554/eLife.63537

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