March 8, 2023

expert reaction to unpublished conference abstract on long COVID symptoms after infection with different variants

A conference abstract (not a published paper) presented at the European Congress of Clinical Microbiology & Infectious Diseases (ECCMID) annual meeting looks at post-COVID condition after vaccination and infection with SARS-CoV-2 variants.

Dr Janet Scott, Clinical Lecturer in Infectious Diseases, University of Glasgow, said:

“This is an interesting abstract, especially that reinfection did not trigger long COVID, but it is difficult to assess the work from the abstract alone. For example – the abstract does not say whether severity of infection has been taken into account. In our previous research, we found that asymptomatic cases did not lead to long COVID (https://www.nature.com/articles/s41467-022-33415-5) and many health care workers tested positive through routine work related swabs, but have few if any symptoms. Also since Omicron occurred in the era of vaccination, and we know vaccination to be effective at preventing long COVID, this may be why Omicron resulted in a lower chance of getting long COVID. The authors may of course have dealt with both of these issues and may discuss it in their presentation at ECCMID”

Prof Danny Altmann, Professor of Immunology, Imperial College London, said:

“This is an interesting healthcare-worker study on Long Covid. At first glance, it’s hard to square the relatively optimistic view here of lack of Long Covid risk following Omicron, with the UK ONS data showing some 700,000 new Long Covid cases during the post-2022 Omicron period. In general, the current view can best be summed up as – Omicron in a highly vaccinated population is associated with lower risk either of severe disease or of Long Covid, yet the prevalence of infections has been so high that the number of Long Covid cases stack up.”

The abstract ‘Evolution of symptoms compatible with post-COVID condition after wild type infection and influence of Omicron BA.1 reinfection and SARS-CoV-2 vaccinations’ was presented at the European Congress of Clinical Microbiology & Infectious Diseases (ECCMID) annual meeting. There is no full paper available.

Declared interests

Dr Janet Scott: “I am involved in completing long COVID research groups, in particular the Covid in Scotland Study (CISS), which is also addressing similar issues but with a much larger sample sizes.”

Prof Danny Altmann has worked in consultancy roles for the vaccine programmes at AstraZeneca, Pfizer and Novavax. Altmann is co-author of the Penguin Handbook of Long Covid.