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. 2020 Dec;9(1):2509-2514.
doi: 10.1080/22221751.2020.1837015.

A multi-family cluster of COVID-19 associated with asymptomatic and pre-symptomatic transmission in Jixi City, Heilongjiang, China, 2020

Hongyang Zhang  1 , Chengcheng Hong  2   3 , Qulu Zheng  4 , Pengzheng Zhou  3 , Yuliang Zhu  1 , Zhongkai Zhang  5 , Qifang Bi  4 , Ting Ma  2   3
Affiliations

A multi-family cluster of COVID-19 associated with asymptomatic and pre-symptomatic transmission in Jixi City, Heilongjiang, China, 2020

Hongyang Zhang et al. Emerg Microbes Infect. 2020 Dec.

Abstract

We investigated a multi-family cluster of 22 cases in Jixi, where pre-symptomatic and asymptomatic transmission resulted in at least 41% of household infections of SARS-CoV-2. Our study illustrates the challenge of controlling COVID-19 due to the presence of asymptomatic and pre-symptomatic transmission even when extensive testing and contact tracing are conducted.

Keywords: Asymptomatic transmission; COVID-19; cluster; contact tracing; household close contact; pre-symptomatic transmission.

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Conflict of interest statement

No potential conflict of interest was reported by the author(s).

Figures

Figure 1.
Figure 1.
Transmission chain of 22 COVID-19 cases associated with a multi-family cluster. (A) Family structure and transmission chains linking all 22 infected patients in the cluster. (B) Duration of exposure to index case, dates of symptom onset, duration of isolation, hospitalization for all close contacts of patients 14, 15, 16, and 19 outside of family A. Exposure history in family A were not presented because of heavily overlapping contact history between cases.
See this image and copyright information in PMC

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