July 10, 2021

expert reaction to conference abstract describing a woman infected with both the alpha and beta variants at the same time

A case report presented at the European Congress of Clinical Microbiology & Infectious Diseases (ECCMID) looks at a 90-year-old lady infected with two SARS-CoV-2 variants of concern; alpha and beta. 

Professor Lawrence Young, Virologist and Professor of Molecular Oncology, Warwick Medical School, University of Warwick, said:

“This is not the first time that infection with more than one variant of SARS-CoV-2 has been detected in the same individual. The reality is that virus variants are being produced all the time in anybody who is infected and these multiple variants are being transmitted to other people who then go on to produce other variants. It is those virus variants with increased fitness that dominant the infection – fitness being defined as an ability to more efficiently infect the cells in our noses and throats and also the ability to dodge our immune systems. Detection of infection with different variants depends on the levels of replication of the individual variants and on the sensitivity of our sequencing technology to detect these variants. Detecting two dominant variants of concern (VOCs) in a single person is not a surprise – these could have been passed on by a single infected individual or by contact with multiple infected people. There is no evidence that this infection with two VOCs was in any way responsible for the clinical outcome in this case. This study does highlight the need for more studies to determine whether infection with multiple VOC affects the clinical course of COVID-19 and whether this in any way compromises the efficacy of vaccination.”

Prof Rowland Kao, the Sir Timothy O’Shea Professor of Veterinary Epidemiology and Data Science, University of Edinburgh, said:

“It’s very difficult to make general conclusions from a single case. It’s worth noting that, with the millions of cases of COVID-19 around the world, there will be at least some individuals who will have been exposed to more than one variant of the virus close enough in time that any immune response due to the first exposure, will have little influence on the probability of infection with the second, once exposed. What would be more concerning is if there was evidence that the second infection occurred substantially after immune protection should have been substantial – as this would indicate immune protection failure. However, even then, unless the rate of occurrence is high, then while potentially unfortunate for the individual (especially if the combination results in more severe infection than a single infection) it would be no cause for general public alarm. Similarly, even if the person infected twice was severely affected, this would only be an additional general concern, if it was found to commonly occur amongst those affected more than once.”

Conference abstract ‘Case report: a 90-year-old lady infected with two CoVID-19 VoCs: 20I/501Y.V1 and 20H/501Y.V2’ has been presented at the European Congress of Clinical Microbiology & Infectious Diseases (ECCMID). It was under embargo until 23:01 UK time Saturday 10 July.

All our previous output on this subject can be seen at this weblink:

www.sciencemediacentre.org/tag/covid-19

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