Transmission and clinical characteristics of COVID-2019 in 104 outside-Wuhan patients, China

Transmission and clinical characteristics of COVID-2019 in 104 outside-Wuhan patients, China. Spencer EA, Heneghan C.

https://www.cebm.net/study/transmission-and-clinical-characteristics-of-covid-2019-in-104-outside-wuhan-patients-china/

Published on July 27, 2020

Reference Qiu C, Deng Z, Xiao Q, et al. Transmission and clinical characteristics of coronavirus disease 2019 in 104 outside-Wuhan patients, China J Med Virol. 2020;10.1002/jmv.25975. doi:10.1002/jmv.25975
Study type
Country China
Setting Contact tracing of hospitalised COVID-19 patients
Funding Details This study was supported by the Natural Science Foundation of Hunan Province, China and Project of Science and Technology of Health Commission of Hunan Province, China.
Transmission mode Close contact, person to person
Exposures Household

Bottom Line

Following implementation of control measures in Hunan Province, household transmission accounted for most cases, suggesting effectiveness of lockdown measures. Transmission from asymptomatic relatives was observed (two cases).

Evidence Summary

In two hospitals in Hunan Province (geographically adjacent to Wuhan), 104 COVID-19 patients were admitted between 22nd January to 23rd February 2020 (mean age was 43 (range 8 to 84) years, and 49 (47%) were male).

Forty six percent (48/104) cases had travelled from Wuhan: 93 (89%) had a definite contact history with infection.  Family clusters were the majority of ongoing transmission. Only three children became infected.

Transmission along the chain of three generations was observed.  Five asymptomatic infected cases were found and two of them infected their relatives.  The median incubation period was 6 (range 1 to 32) days. Family not community transmission became the main context of infections, suggesting the control measures after lockdown were effective.

What did they do?

Contact investigation was conducted on each COVID-19 case admitted to two hospitals in Hunan Province (geographically next to Wuhan) from 22nd January to 23rd February 2020. 

Cases were confirmed by the polymerase chain reaction test. Demographic, clinical, and outcomes were collected and analyzed.

Study reliability

The authors suggest the study’s limitations are that cases are from two hospitals only, they were unable to monitor blood and organ viral load, and follow-up time was not sufficient to comprehensively follow up the final cases.  However, compared with other similar studies these limitations are not prominent.

Clearly defined setting Demographic characteristics described Follow-up length was sufficient Transmission outcomes assessed Main biases are taken into consideration
Yes Yes Unclear Yes Unclear

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.