COVID-19: Household transmission of SARS-CoV-2 in Wuhan.
COVID-19: Household transmission of SARS-CoV-2 in Wuhan. Spencer EA, Heneghan C.
Published on July 8, 2020
Transmission Dynamics of COVID-19
||Wang Z, Ma W, Zheng X, Wu G, Zhang R. Household transmission of SARS-CoV-2. J Infect. 2020;81(1):179-182. 2020
||Households, Wuhan, February 2020
||This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.
||Person to person, Close contact
The observed rate of secondary transmission among household contacts of hospitalised patients with SARS-CoV-2 infection was 30%.
For the 85 study participants, there were 155 household contacts in total.
Among 155 household contacts, 47 (30%) were diagnosed positive for SARS-CoV-2 by RT-PCR assays of throat swabs; 57 (37%) tested negative; 51 (33%) were not tested because they were asymptomatic during quarantine for at least two weeks
Of these 51 untested asymptomatic household contacts, 16 received chest computed X-ray tomography (CT) and showed no signs of viral pneumonia
The infection rate among household contacts was 38% for households containing one contact, 50% for households with two contacts, and 31% for households with three contacts.
What did they do?
On the 13th or 14th, February 2020 85 patients were admitted o Union Hospital, Wuhan with SARS-CoV-2 and their household members were recruited into an observational study.
Cases were confirmed by real-time reverse transcription-polymerase chain reaction assays on throat swabs. Epidemiological, clinical and laboratory data of the household members were collected, and transmission rates observed.
This is a small study in a particular context and results need replication. 51 household contacts did not receive RT-PCR tests and some of them may have been positive (asymptomatic). It is not clear what level of contact took place between household members and the hospitalised cases.
|Clearly defined setting
||Demographic characteristics described
||Follow-up length was sufficient
||Transmission outcomes assessed
||Main biases are taken into consideration
What else should I consider?
About the authors
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
Dr Elizabeth Spencer; MMedSci, PhD. Epidemiologist, Nuffield Department for Primary Care Health Sciences, University of Oxford.