Immune Mechanisms Underpinning Long COVID: Collegium Internationale Allergologicum Update 2024

Eva Untersmayr; Carina Venter; Peter Smith; Johanna Rohrhofer; Cebile Ndwandwe; Jurgen Schwarze; Emer Shannon; Milena Sokolowska; Corinna Sadlier; Liam O'Mahony

doi:10.1159/000535736

Immune Mechanisms Underpinning Long COVID: Collegium Internationale Allergologicum Update 2024

Int Arch Allergy Immunol. 2024 Jan 22:1-14. doi: 10.1159/000535736. Online ahead of print.

Authors

Eva Untersmayr¹, Carina Venter², Peter Smith³, Johanna Rohrhofer¹, Cebile Ndwandwe⁴, Jurgen Schwarze⁵, Emer Shannon⁴, Milena Sokolowska⁶, Corinna Sadlier^{7

8}, Liam O'Mahony^{4

8}

Affiliations

¹ Institute of Pathophysiology and Allergy Research, Center of Pathophysiology, Immunology and Infectiology, Medical University Vienna, Vienna, Austria.
² Section of Allergy and Immunology, Department of Pediatrics, Children's Hospital Colorado, University of Colorado School of Medicine, Aurora, Colorado, USA.
³ Department of Clinical Medicine, Griffiths University, Southport, Queensland, Australia.
⁴ School of Microbiology, APC Microbiome Ireland, University College Cork, Cork, Ireland.
⁵ Centre for Inflammation Research, Institute for Regeneration and Repair, University of Edinburgh, Edinburgh, UK.
⁶ Swiss Institute of Allergy and Asthma Research, University of Zurich, Zurich, Switzerland.
⁷ Department of Infectious Diseases, Cork University Hospital, Cork, Ireland.
⁸ Department of Medicine, University College Cork, Cork, Ireland.

PMID: 38253027
DOI: 10.1159/000535736

Abstract

Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection can result in a prolonged multisystem disorder termed long COVID, which may affect up to 10% of people following coronavirus disease 2019 (COVID-19). It is currently unclear why certain individuals do not fully recover following SARS-CoV-2 infection.

Summary: In this review, we examine immunological mechanisms that may underpin the pathophysiology of long COVID. These mechanisms include an inappropriate immune response to acute SARS-CoV-2 infection, immune cell exhaustion, immune cell metabolic reprogramming, a persistent SARS-CoV-2 reservoir, reactivation of other viruses, inflammatory responses impacting the central nervous system, autoimmunity, microbiome dysbiosis, and dietary factors.

Key messages: Unfortunately, the currently available diagnostic and treatment options for long COVID are inadequate, and more clinical trials are needed that match experimental interventions to underlying immunological mechanisms.

Keywords: Inflammation; Long COVID; Microbiota; Severe acute respiratory syndrome coronavirus 2.

Publication types

Review