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. 2021 Mar 5;18(5):2621.
doi: 10.3390/ijerph18052621.

Defining Post-COVID Symptoms (Post-Acute COVID, Long COVID, Persistent Post-COVID): An Integrative Classification

César Fernández-de-Las-Peñas  1 , Domingo Palacios-Ceña  1 , Víctor Gómez-Mayordomo  2 , María L Cuadrado  2   3 , Lidiane L Florencio  1
Affiliations

Defining Post-COVID Symptoms (Post-Acute COVID, Long COVID, Persistent Post-COVID): An Integrative Classification

César Fernández-de-Las-Peñas et al. Int J Environ Res Public Health. .

Abstract

The pandemic of the coronavirus disease 2019 (COVID-19) has provoked a second pandemic, the "long-haulers", i.e., individuals presenting with post-COVID symptoms. We propose that to determine the presence of post-COVID symptoms, symptoms should appear after the diagnosis of SARS-CoV-2 infection; however, this situation has some problems due to the fact that not all people infected by SARS-CoV-2 receive such diagnosis. Based on relapsing/remitting nature of post-COVID symptoms, the following integrative classification is proposed: potentially infection related-symptoms (up to 4-5 weeks), acute post-COVID symptoms (from week 5 to week 12), long post-COVID symptoms (from week 12 to week 24), and persistent post-COVID symptoms (lasting more than 24 weeks). The most important topic is to establish the time reference points. The classification also integrates predisposing intrinsic and extrinsic factors and hospitalization data which could promote post-COVID symptoms. The plethora of symptoms affecting multiple systems exhibited by "long-haulers" suggests the presence of different underlying mechanisms.

Keywords: COVID-19; classification; definition; long COVID; persistent; symptoms.

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Conflict of interest statement

The authors declare no conflict of interest.

Figures

Figure 1
Figure 1
Integrative post-COVID symptoms model in non-hospitalized patients showing transition phase (blue), and phases 1 (green), 2 (yellow), and 3 (red) of post-COVID symptoms. PTSD: post-traumatic stress disorder.
Figure 2
Figure 2
Integrative post-COVID symptoms model in hospitalized patients showing transition phase (blue), and phases 1 (green), 2 (yellow), and 3 (red) of post-COVID symptoms. PTSD: post-traumatic stress disorder.
Figure 3
Figure 3
Integrative post-COVID symptoms model in asymptomatic individuals showing transition phase (blue), and phases 1 (green), 2 (yellow), and 3 (red) of post-COVID symptoms. PTSD: post-traumatic stress disorder.
See this image and copyright information in PMC

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References

    1. Marshall M. The lasting misery of coronavirus long-haulers. Nature. 2020;585:339–341. doi: 10.1038/d41586-020-02598-6. - DOI - PubMed
    1. Rubin R. As their numbers grow, COVID-19 “Long Haulers” stump experts. JAMA. 2020 doi: 10.1001/jama.2020.17709. online ahead of print. - DOI - PubMed
    1. No authors listed Long COVID: Let patients help define long-lasting COVID symptoms. Nature. 2020;586:170. doi: 10.1038/d41586-020-02796-2. - DOI - PubMed
    1. Callard F., Perego E. How and why patients made Long Covid. Soc. Sci. Med. 2021;268:113426. doi: 10.1016/j.socscimed.2020.113426. - DOI - PMC - PubMed
    1. The Lancet Facing up to long COVID. Lancet. 2020;396:1861. doi: 10.1016/S0140-6736(20)32662-3. - DOI - PMC - PubMed

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