Skip to main content

Main menu

  • Home
  • Articles
    • Current
    • Special Feature Articles - Most Recent
    • Special Features
    • Colloquia
    • Collected Articles
    • PNAS Classics
    • List of Issues
  • Front Matter
    • Front Matter Portal
    • Journal Club
  • News
    • For the Press
    • This Week In PNAS
    • PNAS in the News
  • Podcasts
  • Authors
    • Information for Authors
    • Editorial and Journal Policies
    • Submission Procedures
    • Fees and Licenses
  • Submit
  • Submit
  • About
    • Editorial Board
    • PNAS Staff
    • FAQ
    • Accessibility Statement
    • Rights and Permissions
    • Site Map
  • Contact
  • Journal Club
  • Subscribe
    • Subscription Rates
    • Subscriptions FAQ
    • Open Access
    • Recommend PNAS to Your Librarian

User menu

  • Log in
  • My Cart

Search

  • Advanced search
Home
Home
  • Log in
  • My Cart

Advanced Search

  • Home
  • Articles
    • Current
    • Special Feature Articles - Most Recent
    • Special Features
    • Colloquia
    • Collected Articles
    • PNAS Classics
    • List of Issues
  • Front Matter
    • Front Matter Portal
    • Journal Club
  • News
    • For the Press
    • This Week In PNAS
    • PNAS in the News
  • Podcasts
  • Authors
    • Information for Authors
    • Editorial and Journal Policies
    • Submission Procedures
    • Fees and Licenses
  • Submit
Research Article

Identifying airborne transmission as the dominant route for the spread of COVID-19

Renyi Zhang, View ORCID ProfileYixin Li, Annie L. Zhang, View ORCID ProfileYuan Wang, and Mario J. Molina
  1. aDepartment of Atmospheric Sciences, Texas A&M University, College Station, TX 77843;
  2. bDepartment of Chemistry, Texas A&M University, College Station, TX 77843;
  3. cDepartment of Chemistry, College of Natural Sciences, The University of Texas at Austin, Austin, TX 78712;
  4. dDivision of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125;
  5. eDepartment of Chemistry and Biochemistry, University of California San Diego, La Jolla, CA 92093

See allHide authors and affiliations

PNAS June 30, 2020 117 (26) 14857-14863; first published June 11, 2020; https://doi.org/10.1073/pnas.2009637117
Renyi Zhang
aDepartment of Atmospheric Sciences, Texas A&M University, College Station, TX 77843;
bDepartment of Chemistry, Texas A&M University, College Station, TX 77843;
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
  • For correspondence: renyi-zhang@tamu.edu mjmolina@ucsd.edu
Yixin Li
bDepartment of Chemistry, Texas A&M University, College Station, TX 77843;
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
  • ORCID record for Yixin Li
Annie L. Zhang
cDepartment of Chemistry, College of Natural Sciences, The University of Texas at Austin, Austin, TX 78712;
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Yuan Wang
dDivision of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125;
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
  • ORCID record for Yuan Wang
Mario J. Molina
eDepartment of Chemistry and Biochemistry, University of California San Diego, La Jolla, CA 92093
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
  • For correspondence: renyi-zhang@tamu.edu mjmolina@ucsd.edu
  1. Contributed by Mario J. Molina, May 16, 2020 (sent for review May 14, 2020; reviewed by Manish Shrivastava and Tong Zhu)

  • Article
  • Figures & SI
  • Info & Metrics
  • PDF
Loading

Significance

We have elucidated the transmission pathways of coronavirus disease 2019 (COVID-19) by analyzing the trend and mitigation measures in the three epicenters. Our results show that the airborne transmission route is highly virulent and dominant for the spread of COVID-19. The mitigation measures are discernable from the trends of the pandemic. Our analysis reveals that the difference with and without mandated face covering represents the determinant in shaping the trends of the pandemic. This protective measure significantly reduces the number of infections. Other mitigation measures, such as social distancing implemented in the United States, are insufficient by themselves in protecting the public. Our work also highlights the necessity that sound science is essential in decision-making for the current and future public health pandemics.

Abstract

Various mitigation measures have been implemented to fight the coronavirus disease 2019 (COVID-19) pandemic, including widely adopted social distancing and mandated face covering. However, assessing the effectiveness of those intervention practices hinges on the understanding of virus transmission, which remains uncertain. Here we show that airborne transmission is highly virulent and represents the dominant route to spread the disease. By analyzing the trend and mitigation measures in Wuhan, China, Italy, and New York City, from January 23 to May 9, 2020, we illustrate that the impacts of mitigation measures are discernable from the trends of the pandemic. Our analysis reveals that the difference with and without mandated face covering represents the determinant in shaping the pandemic trends in the three epicenters. This protective measure alone significantly reduced the number of infections, that is, by over 75,000 in Italy from April 6 to May 9 and over 66,000 in New York City from April 17 to May 9. Other mitigation measures, such as social distancing implemented in the United States, are insufficient by themselves in protecting the public. We conclude that wearing of face masks in public corresponds to the most effective means to prevent interhuman transmission, and this inexpensive practice, in conjunction with simultaneous social distancing, quarantine, and contact tracing, represents the most likely fighting opportunity to stop the COVID-19 pandemic. Our work also highlights the fact that sound science is essential in decision-making for the current and future public health pandemics.

  • COVID-19
  • virus
  • aerosol
  • public health
  • pandemic

Footnotes

  • ↵1To whom correspondence may be addressed. Email: renyi-zhang{at}tamu.edu or mjmolina{at}ucsd.edu.
  • Author contributions: R.Z. designed research; R.Z., Y.L., and Y.W. performed research; R.Z., Y.L., Y.W., and M.J.M. analyzed data; and R.Z., A.L.Z., and M.J.M. wrote the paper.

  • Reviewers: M.S., Pacific Northwest National Laboratory; and T.Z., Peking University.

  • The authors declare no competing interest.

  • This article contains supporting information online at https://www.pnas.org/lookup/suppl/doi:10.1073/pnas.2009637117/-/DCSupplemental.

  • Copyright © 2020 the Author(s). Published by PNAS.

This open access article is distributed under Creative Commons Attribution License 4.0 (CC BY).

View Full Text
PreviousNext
Back to top
Article Alerts
Email Article

Thank you for your interest in spreading the word on PNAS.

NOTE: We only request your email address so that the person you are recommending the page to knows that you wanted them to see it, and that it is not junk mail. We do not capture any email address.

Enter multiple addresses on separate lines or separate them with commas.
Identifying airborne transmission as the dominant route for the spread of COVID-19
(Your Name) has sent you a message from PNAS
(Your Name) thought you would like to see the PNAS web site.
CAPTCHA
This question is for testing whether or not you are a human visitor and to prevent automated spam submissions.
Citation Tools
Identifying airborne transmission as the dominant route for the spread of COVID-19
Renyi Zhang, Yixin Li, Annie L. Zhang, Yuan Wang, Mario J. Molina
Proceedings of the National Academy of Sciences Jun 2020, 117 (26) 14857-14863; DOI: 10.1073/pnas.2009637117

Citation Manager Formats

  • BibTeX
  • Bookends
  • EasyBib
  • EndNote (tagged)
  • EndNote 8 (xml)
  • Medlars
  • Mendeley
  • Papers
  • RefWorks Tagged
  • Ref Manager
  • RIS
  • Zotero
Request Permissions
Share
Identifying airborne transmission as the dominant route for the spread of COVID-19
Renyi Zhang, Yixin Li, Annie L. Zhang, Yuan Wang, Mario J. Molina
Proceedings of the National Academy of Sciences Jun 2020, 117 (26) 14857-14863; DOI: 10.1073/pnas.2009637117
del.icio.us logo Digg logo Reddit logo Twitter logo CiteULike logo Facebook logo Google logo Mendeley logo
  • Tweet Widget
  • Facebook Like
  • Mendeley logo Mendeley

Article Classifications

  • Social Sciences
  • Environmental Sciences
  • Physical Sciences
  • Earth, Atmospheric, and Planetary Sciences

This article has Letters. Please see:

  • Relationship between Research Article and Letter - October 06, 2020
  • Relationship between Research Article and Letter - October 13, 2020
Proceedings of the National Academy of Sciences: 117 (26)
Table of Contents

Submit

Sign up for Article Alerts

Jump to section

  • Article
    • Abstract
    • Distinct Pandemic Trends in the Three Epicenters
    • Understanding the Impacts of Face Covering
    • Dominant Airborne Transmission
    • A Policy Perspective
    • Conclusions
    • Methods
    • Acknowledgments
    • Footnotes
    • References
  • Figures & SI
  • Info & Metrics
  • PDF

You May Also be Interested in

Setting sun over a sun-baked dirt landscape
Core Concept: Popular integrated assessment climate policy models have key caveats
Better explicating the strengths and shortcomings of these models will help refine projections and improve transparency in the years ahead.
Image credit: Witsawat.S.
Model of the Amazon forest
News Feature: A sea in the Amazon
Did the Caribbean sweep into the western Amazon millions of years ago, shaping the region’s rich biodiversity?
Image credit: Tacio Cordeiro Bicudo (University of São Paulo, São Paulo, Brazil), Victor Sacek (University of São Paulo, São Paulo, Brazil), and Lucy Reading-Ikkanda (artist).
Syrian archaeological site
Journal Club: In Mesopotamia, early cities may have faltered before climate-driven collapse
Settlements 4,200 years ago may have suffered from overpopulation before drought and lower temperatures ultimately made them unsustainable.
Image credit: Andrea Ricci.
Click beetle on a leaf
How click beetles jump
Marianne Alleyna, Aimy Wissa, and Ophelia Bolmin explain how the click beetle amplifies power to pull off its signature jump.
Listen
Past PodcastsSubscribe
Birds nestling on tree branches
Parent–offspring conflict in songbird fledging
Some songbird parents might improve their own fitness by manipulating their offspring into leaving the nest early, at the cost of fledgling survival, a study finds.
Image credit: Gil Eckrich (photographer).

Similar Articles

Site Logo
Powered by HighWire
  • Submit Manuscript
  • Twitter
  • Facebook
  • RSS Feeds
  • Email Alerts

Articles

  • Current Issue
  • Special Feature Articles – Most Recent
  • List of Issues

PNAS Portals

  • Anthropology
  • Chemistry
  • Classics
  • Front Matter
  • Physics
  • Sustainability Science
  • Teaching Resources

Information

  • Authors
  • Editorial Board
  • Reviewers
  • Subscribers
  • Librarians
  • Press
  • Site Map
  • PNAS Updates
  • FAQs
  • Accessibility Statement
  • Rights & Permissions
  • About
  • Contact

Feedback    Privacy/Legal

Copyright © 2021 National Academy of Sciences. Online ISSN 1091-6490