SARS-CoV-2 clusters in the UK, France, and Spain

SARS-CoV-2 cluster in the UK, France, and Spain. Spencer EA, Heneghan C.

https://www.cebm.net/study/covid-19-sars-cov-2-clusters-in-the-uk-france-and-spain/

Published on July 23, 2020

Reference Hodcroft EB. Preliminary case report on the SARS-CoV-2 cluster in the UK, France, and Spain. Swiss Med Wkly. 2020;150(9-10):10.4414/smw.2020.20212. Published 2020 Feb 27. 2020
Study type
Country UK, France, Spain
Setting French ski resort
Funding Details Non reported
Transmission mode Person to person, Close contact
Exposures Travel, Apartment sharing

Bottom Line

This preliminary report shows that 21 people were established to be associated with a COVID-19 case in a ski resort in France that led to 12  subsequent infections in France, UK and Spain.

Evidence Summary

The focal case was a middle-aged British man who attended a conference at the Grand Hyatt hotel, Singapore, from 20th to 23rd January, where he is believed to have become infected with SARS-CoV-2.

There are descriptions of the movements and contacts of the focal case, his contacts and subsequent infections. These vary in detail and likely accuracy.

What did they do?

A cluster of cases apparently originating from a UK citizen who attended a conference in Singapore and subsequently stayed in a French ski resort was investigated. 

The focal case was a middle-aged British man who attended a conference at the Grand Hyatt hotel, Singapore, from 20th to 23rd January, where he is believed to have become infected with SARS-CoV-2

After leaving Singapore, the focal case arrived in the French skiing resort of Contamines-Monjoie, in Haute-Savoie, on the 24th January, spending a four-day holiday in a chalet before returning to the UK on the 28th of January. 

The chalet reportedly contains (at least) two apartments.  From media reports and statements, all twenty-one people who can be traced back to the ski resort (including the focal case) are British nationals.

Details of the focal case’s movements from Singapore through France to the UK are described, including visiting a pub and attending a yoga class. 

Study reliability

It is hard to know how reliable this evidence is, as the author points out the data on contact and movements are very difficult to obtain and be sure about.  There is confusion as to the evidence on the movements of the focal case and the author reports that some of the reported movements may be by another individual rather than the focal case. Such difficulties make studies like this very difficult to achieve and mean that the results must be considered with caution. The author points out that the lack of detail on the type and duration of contact between the focal case and other individuals at the ski resort in France hampers the investigation.

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

What else should I consider?

This report describes transmission from the French ski resort which is also covered by other reports. 

Updated versions of Figure 1 and Figure 2 can be found online at github.com/emmahodcroft/BritishCOVID19-Cluster

About the authors

Carl Heneghan

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

Elizabeth Spencer

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