Cited by 16,575COVID-19 epidemiological studiesSARS-CoV-2 and COVID-19 ResearchCOVID-19 Clinical Research Studies

Early transmission dynamics in Wuhan, China, of novel coronavirus-infected pneumonia

Open access
Li, Qun, Guan, Xuhua, Wu, Peng, Wang, Xiaoye, Zhou, Lei, Tong, Yeqing, Ren, Ruiqi, Leung, Kathy S.M. +37 more·2020·New England Journal of Medicine

Abstract

BACKGROUND: The initial cases of novel coronavirus (2019-nCoV)-infected pneumonia (NCIP) occurred in Wuhan, Hubei Province, China, in December 2019 and January 2020. We analyzed data on the first 425 confirmed cases in Wuhan to determine the epidemiologic characteristics of NCIP. METHODS: We collected information on demographic characteristics, exposure history, and illness timelines of laboratory-confirmed cases of NCIP that had been reported by January 22, 2020. We described characteristics of the cases and estimated the key epidemiologic time-delay distributions. In the early period of exponential growth, we estimated the epidemic doubling time and the basic reproductive number. RESULTS: Among the first 425 patients with confirmed NCIP, the median age was 59 years and 56% were male. The majority of cases (55%) with onset before January 1, 2020, were linked to the Huanan Seafood Wholesale Market, as compared with 8.6% of the subsequent cases. The mean incubation period was 5.2 days (95% confidence interval [CI], 4.1 to 7.0), with the 95th percentile of the distribution at 12.5 days. In its early stages, the epidemic doubled in size every 7.4 days. With a mean serial interval of 7.5 days (95% CI, 5.3 to 19), the basic reproductive number was estimated to be 2.2 (95% CI, 1.4 to 3.9). CONCLUSIONS: On the basis of this information, there is evidence that human-to-human transmission has occurred among close contacts since the middle of December 2019. Considerable efforts to reduce transmission will be required to control outbreaks if similar dynamics apply elsewhere. Measures to prevent or reduce transmission should be implemented in populations at risk. (Funded by the Ministry of Science and Technology of China and others.).

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Authors
Li, Q., Guan, X., Wu, P., Wang, X., Zhou, L., Tong, Y., Ren, R., Leung, K. S. M., Lau, E. H. Y., Wong, J. Y., Xing, X., Xiang, N., Wu, Y., Li, C., Chen, Q., Li, D., Liu, T., Zhao, J., Liu, M., Tu, W., Chen, C., Jin, L., Yang, R., Wang, Q., Zhou, S., Wang, R., Liu, H., Luo, Y., Liu, Y., Shao, G., Li, H., Tao, Z., Yang, Y., Deng, Z., Liu, B., Ma, Z., Zhang, Y., Shi, G., Lam, T. T. Y., Wu, J. T., Gao, G. F., Cowling, B. J., Yang, B., Leung, G. M., & Feng, Z.
Affiliations
Chinese Center For Disease Control and Prevention (CN)
Corresponding author
Cowling, Benjamin J.
Venue
New England Journal of Medicine
Published
2020-03-26
Volume
382
Issue
13
Pages
1199-1207
ISSN
  • 0028-4793 (ISSN-L)
  • 1533-4406
OpenAlex
W3003668884
Cited by
16,575
References
20
Citations by year
2026: 133 · 2025: 310 · 2024: 632 · 2023: 1332 · 2022: 2476 · 2021: 4607 · 2020: 7047 · 2019: 10 · 2018: 5 · 2017: 1 · 2013: 1
FWCI
615.39
Type
journal article
Language
en
Open access
Locations
  • New England Journal of Medicine (publishedVersion)
  • PubMed Central (publishedVersion)
  • PubMed (publishedVersion)
  • Figshare (submittedVersion, cc-by)
Funders
  • Ministry of Science and Technology (KJYJ-2013-01-02)
  • National Natural Science Foundation of China (71934002)
  • National Institute of Allergy and Infectious Diseases (HHSN272201400006C)
  • Health and Medical Research Fund
Topics
  • Physical Sciences › Mathematics › Modeling and Simulation › COVID-19 epidemiological studies
  • Health Sciences › Medicine › Infectious Diseases › SARS-CoV-2 and COVID-19 Research
  • Health Sciences › Medicine › Infectious Diseases › COVID-19 Clinical Research Studies
Keywords
novel coronavirus, SARS-CoV-2, COVID-19 pandemic, transmission dynamics, Wuhan, incubation period, serial interval, epidemic doubling time, basic reproduction number, human-to-human transmission, epidemic control
MeSH terms
Betacoronavirus, COVID-19, SARS-CoV-2, Adolescent, Adult, Aged, China, Communicable Disease Control, Female, Humans, Male, Middle Aged, Pneumonia, Viral, Incidence, Polymerase Chain Reaction, Coronavirus Infections, Disease Transmission, Infectious, Infectious Disease Incubation Period, Young Adult, Epidemics, Pandemics

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