TUESDAY, 9 FEBRUARY 2021As COVID-19 cases worldwide surge past 100 million, a feature of the disease which is quickly becoming more documented is the duration of its effects. In December, data published by the Office for National Statistics suggested that one in 10 people experienced ‘long COVID’, where symptoms of the coronavirus lasted three months or more.
New research from scientists at the University of Cambridge and Addenbrooke’s Hospital has looked at over 200 patients, from asymptomatic healthcare workers to those requiring mechanical ventilation. Blood samples over several months has given insight into how quickly the immune system recovers and how this may relate to ‘long COVID’.
The team found that defective immune recovery from the virus might drive ongoing disease and longer-term effects, as well as a secondary immunodeficiency leading to increased risk of subsequent infection. Often, profound alterations to immune cells were found to persist weeks or months after infection. Some of these cells recovered as inflammation resolved, or even before, while others remained markedly abnormal even after resolution of systemic inflammation and when patients had been discharged from hospital.
Dr Laura Bergamaschi, the study’s first author, said: “It’s these populations of immune cells that still show abnormalities…that might be of importance in ‘long COVID’. For some cell types, it may be that they are just slow to regenerate, but for others…it appears something is continuing to drive their activity. The more we understand about this, the more likely we will be able to better treat patients whose lives continue to be blighted by the after-effects of COVID-19.”
‘Long COVID’ is here to stay it seems, for now at least. With vaccination underway across the world, and promising data coming from Israel, there is cause for optimism but this must be accompanied by further research, and eventually treatments, for this persistent form of the disease.
James Lee is a graduate of Translational Biomedical Research (MPhil) from Homerton College.
Bergamaschi, L et al. Early immune pathology and persistent dysregulation characterise severe COVID-19. MedRXiV; 15 Jan 2021; DOI: 10.1101/2021.01.11.20248765