COVID-19: Transmission within a family cluster by presymptomatic carriers in China

COVID-19: Transmission within a family cluster by presymptomatic carriers in China. Spencer EA, Heneghan C.

Published on July 23, 2020

Reference Guoqing Qian, Naibin Yang, Ada Hoi Yan Ma, Liping Wang, Guoxiang Li, Xueqin Chen, Xiaomin Chen. COVID-19 Transmission Within a Family Cluster by Presymptomatic Carriers in China Clinical Infectious Diseases. ciaa316 2020
Study type
Country China
Setting Family
Funding Details Supported by the Natural Science Foundation of Zhejiang Province
Transmission mode Presymptomatic
Exposures Family contacts

Bottom Line

Within a family cluster of eight  cases among nine family members, clinical manifestations varied from asymptomatic to severe pneumonia, and timing of symptom onset varied.

Evidence Summary

Among nine family members, eight  were laboratory-confirmed with COVID-19, and a 6-year-old child had no evidence of infection. 

Among the eight  cases, one adult and a 13-month-old infant were asymptomatic; one adult was diagnosed as having severe pneumonia.

What did they do?

A family cluster of coronavirus disease 2019 (COVID-19) caused by a presymptomatic case. 9 family members lived in three households, in Zhejiang province, outside Wuhan.

Study reliability

This is a report of a small cluster of cases within one family.

Clearly defined setting Demographic characteristics described Follow-up length was sufficient Transmission outcomes assessed Main biases are taken into consideration
Yes Yes Yes Yes No

What else should I consider?

About the authors

Carl Heneghan

Carl is Professor of EBM & Director of CEBM at the University of Oxford. He is also a GP and tweets @carlheneghan. He has an active interest in discovering the truth behind health research findings

Elizabeth Spencer

Dr Elizabeth Spencer; MMedSci, PhD. Epidemiologist, Nuffield Department for Primary Care Health Sciences, University of Oxford.