Impact of international travel and border control measures on the global spread of the novel 2019 coronavirus outbreak
Open accessAbstract
The novel coronavirus outbreak (COVID-19) in mainland China has rapidly spread across the globe. Within 2 mo since the outbreak was first reported on December 31, 2019, a total of 566 Severe Acute Respiratory Syndrome (SARS CoV-2) cases have been confirmed in 26 other countries. Travel restrictions and border control measures have been enforced in China and other countries to limit the spread of the outbreak. We estimate the impact of these control measures and investigate the role of the airport travel network on the global spread of the COVID-19 outbreak. Our results show that the daily risk of exporting at least a single SARS CoV-2 case from mainland China via international travel exceeded 95% on January 13, 2020. We found that 779 cases (95% CI: 632 to 967) would have been exported by February 15, 2020 without any border or travel restrictions and that the travel lockdowns enforced by the Chinese government averted 70.5% (95% CI: 68.8 to 72.0%) of these cases. In addition, during the first three and a half weeks of implementation, the travel restrictions decreased the daily rate of exportation by 81.3% (95% CI: 80.5 to 82.1%), on average. At this early stage of the epidemic, reduction in the rate of exportation could delay the importation of cases into cities unaffected by the COVID-19 outbreak, buying time to coordinate an appropriate public health response.
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By the Jan 23, 2020 lockdown in Wuhan, infectious individuals had already dispersed to many other parts of the world.
“By the time of the Jan 23, 2020 lockdown in Wuhan, infectious individuals had already dispersed to many other parts of the world.101”
From The Lancet Commission on lessons for the future from the COVID-19 pandemic (2022) · cites this paper as [101]
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- Authors
- Wells, C. R., Sah, P., Moghadas, S. M., Pandey, A., Shoukat, A., Wang, Y., Wang, Z., Meyers, L. A., Singer, B. H., & Galvani, A. P.
- Affiliations
- Yale University (US)
- York University (CA)
- Chinese Academy of Sciences (CN)
- Santa Fe Institute (US)
- University of Florida (US)
- Corresponding author
- Singer, Burton H.
- ORCID
- Venue
- Proceedings of the National Academy of Sciences
- Publisher
- National Academy of Sciences
- Published
- 2020-03-13
- Volume
- 117
- Issue
- 13
- Pages
- 7504-7509
- ISSN
- 0027-8424 (ISSN-L)
- 1091-6490
- PMC
- PMC7132249
- OpenAlex
- W3011999140
- Cited by
- 551
- References
- 18
- Citations by year
- 2026: 15 · 2025: 26 · 2024: 25 · 2023: 44 · 2022: 104 · 2021: 184 · 2020: 152
- FWCI
- 19.22
- Type
- journal article
- Language
- en
- Open access
- hybrid
- doi.org
- Licence
- Locations
- Proceedings of the National Academy of Sciences (publishedVersion, cc-by)
- PubMed Central (publishedVersion, cc-by)
- PubMed (publishedVersion)
- Funders
- National Institutes of Health (UO1-GM087719)
- Burnett and Stender families foundation (Endowment funds to Alison Galvani, Yale University)
- Notsew Orm Sands Foundation (Endowmwnt funds to Yale Universitty)
- Topics
- Physical Sciences › Mathematics › Modeling and Simulation › COVID-19 epidemiological studies
- Health Sciences › Medicine › Public Health, Environmental and Occupational Health › Travel-related health issues
- Health Sciences › Medicine › Infectious Diseases › SARS-CoV-2 and COVID-19 Research
- Keywords
- COVID-19 pandemic, SARS-CoV-2, international travel restrictions, border control measures, global spread, public health response
- MeSH terms
- Betacoronavirus, COVID-19, SARS-CoV-2, China, Communicable Disease Control, Humans, Mass Screening, Pneumonia, Viral, Public Health, Risk, Travel, Global Health, Incidence, Likelihood Functions, Coronavirus Infections, Internationality, Epidemics, Pandemics
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