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. 2021 Jan;27(1):86-93.
doi: 10.1038/s41591-020-01178-5. Epub 2020 Nov 30.

Effective control of SARS-CoV-2 transmission in Wanzhou, China

Qiuling Shi #  1   2 , Yaoyue Hu #  1 , Bin Peng #  1 , Xiao-Jun Tang #  1 , Wei Wang  1 , Kun Su  3 , Chao Luo  4 , Bo Wu  4 , Fan Zhang  1 , Yong Zhang  1 , Benjamin Anderson  5 , Xiao-Ni Zhong  1 , Jing-Fu Qiu  6 , Cheng Yong Yang  7 , Ai-Long Huang  8
Affiliations

Effective control of SARS-CoV-2 transmission in Wanzhou, China

Qiuling Shi et al. Nat Med. 2021 Jan.

Abstract

The effectiveness of control measures to contain coronavirus disease 2019 (COVID-19) in Wanzhou, China was assessed. Epidemiological data were analyzed for 183 confirmed COVID-19 cases and their close contacts from five generations of transmission of severe acute respiratory syndrome coronavirus 2 throughout the entire COVID-19 outbreak in Wanzhou. Approximately 67.2% and 32.8% of cases were symptomatic and asymptomatic, respectively. Asymptomatic and presymptomatic transmission accounted for 75.9% of the total recorded transmission. The reproductive number was 1.64 (95% confidence interval: 1.16-2.40) for G1-to-G2 transmission, decreasing to 0.31-0.39 in later generations, concomitant with implementation of rigorous control measures. Substantially higher infection risk was associated with contact within 5 d after the infectors had been infected, frequent contact and ≥8 h of contact duration. The spread of COVID-19 was effectively controlled in Wanzhou by breaking the transmission chain through social distancing, extensive contact tracing, mass testing and strict quarantine of close contacts.

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References

    1. Zhou, P. et al. A pneumonia outbreak associated with a new coronavirus of probable bat origin. Nature 579, 270–273 (2020). - DOI
    1. National Bureau of Statistics of China. China Statistical Yearbook 2019 (China Statistics Press, 2019).
    1. Bai, Y. et al. Presumed asymptomatic carrier transmission of COVID-19. JAMA 323, 1406–1407 (2020). - DOI
    1. Ye, F. et al. Delivery of infection from asymptomatic carriers of COVID-19 in a familial cluster. Int. J. Infect. Dis. 94, 133–138 (2020). - DOI
    1. Chen, Y. et al. The epidemiological characteristics of infection in close contacts of COVID-19 in Ningbo city. Zhonghua Liu Xing Bing Xue Za Zhi 41, 668–672 (2020).

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