Long covid could be four different syndromes, review suggests
BMJ 2020; 371 doi: https://doi.org/10.1136/bmj.m3981 (Published 14 October 2020) Cite this as: BMJ 2020;371:m3981Read our latest coverage of the coronavirus outbreak
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Dear Editor,
With reference to this interesting article, I think we should also pay attention to another emerging issue of concern, namely that of SARS-CoV-2 reinfections, which are increasingly reported from several Countries, with severe health impacts being observed in some individuals.
In this respect, it would be important to assess whether (and to what extent) "long CoViD-19"-affected patients have developed such condition alongside or secondarily to a SARS-CoV-2 reinfection.
Noteworthy, the genetic "make-up" of the coronaviral strains/isolates recovered from SARS-CoV-2 "reinfected" people is (more or less) diverging from that of the virus strains/isolates originally infecting those individuals, with this arguing in favour of a "SARS-CoV-2 reinfection".
Notwithstanding the above, which appears to be largely plausible, I wonder to what extent we have adequately taken into account the additional possibility that, following a "primary" infection, the viral pathogen could hide itself "somewhere" within the host's body tissues, thereby giving rise to a "mutation process" leading to a virus with a genetic structure different from that of the original viral strain/isolate.
Human immunodeficiency virus (HIV) is a very remarkable example within such context, with the viral strains/isolates primarily entering the human body undergoing a number of mutations, so that the HIV strains/isolates subsequently shed into the surrounding environment and/or transmitted to uninfected hosts will be characterized by a different genetic background.
In the course of HIV infection patients will develop, in their turn, a range of "antibody waves", with the aim of counteracting the various "viral mutants" progressively showing up, with this contributing to the immune deficiency especially seen in Th2-dominant, HIV-infected individuals.
Many question marks are still open regarding the anti-SARS-CoV-2 host's immune response, with "cytokine storm" (otherwise called "cytokine release syndrome"), "macrophage activation syndrome", "Kawasaki-like disease", "antiviral antibody-dependent (immune response) enhancement" and "autoantibody production" (et cetera) being all pieces of an identical "puzzle" encompassing the most severe CoViD-19 phenotypes.
Should viral persistence - and its associated viral genomic mutations - provide an explanatory key to the currently termed "SARS-CoV-2 reinfections", then the hyperactive immune response put in place by the host through consecutive antiviral "antibody waves" could represent, in my opinion, a largely plausible biologic determinant for the severe CoViD-19 forms experienced by some "SARS-CoV-2 reinfected" patients.
As a concluding remark, this is a particularly relevant issue in SARS-CoV-2 infection's pathogenesis, warranting further investigation.
Competing interests: No competing interests
Dear Editor
Although as a doctor-patient with long covid I am grateful for anything which raises the profile of this condition, this approach however raises some concerns.
This is a new virus. There is a lot we don't yet know about the mechanism of organ damage and how to diagnose it.
Also, post-viral fatigue is not, I think we can all now agree, a psychological problem. It is rather an under researched complication of viral illness with massive overlaps with dysautonomia and MCAS.
It is perfectly possible post-covid to have a scarred myocardium from myocarditis, ongoing fatigue and other classic long covid symptoms.
So, I think this division into four groups is worse than unhelpful, I think it's dangerous as it reduces curiosity and attempts to give comfortable and familiar, although meaningless, labels to those with, for example, predominant fatigue.
Instead we need to keep fighting to understand why this virus does what it does, and in so doing, we will surely unlock much of what has previously been labeled as CFS, MCAS and Dysautonomia. This pandemic is an opportunity to understand both this virus and post-viral conditions in general. Let's keep an open and curious mind.
Competing interests: No competing interests
Dear Editor,
What follows after the SARS-CoV-2 infection is yet to fully unfold.
1) There are people who contracted the SARS-CoV-2 infection but had no symptoms. Some of them are likely to develop certain manifestations some time later.
2) There are people with overt symptoms of varied severity and duration. They are likely to develop various manifestations after virus apparently becomes undetectable.
3) The Relapse or Reinfection with SARS-CoV-2 and their manifestations and sequelae.
4) Manifestations caused by other factors in the SARS-CoV-2 in CoVID-19 patients.
5) Impact of the Pandemic on people not infected by SARS-CoV-2.
Let us not be rigid. Let us not be bound down by terminology.
Let us have an open mind, a watchful brain, keen observation, compassionate attitude, staunch determination and concerted efforts to rise above the ruins of the Pandemic.
Arvind Joshi,
MBBS MD FCGP FAMS FICP.
Competing interests: No competing interests
Re: Long covid could be four different syndromes, review suggests
Dear Editor
As a locum public health consultant contributing to the NHS Scotland response to Covid-19 and hospitalised myself last week with ongoing chest pain and subsequent investigation of abnormal ECG results (following likely covid infection when testing was not widely accessible), I am in complete agreement with Dr Blair's earlier response on the unhelpfulness of the proposed four different ‘Covid syndromes’ proposed in the original article.
Surely any sub-categorisation which risks diverting our efforts to fully investigate the sequelae and medium to longer term pathology of Covid-19 infection is likely to be an unnecessary distraction. The extent of the challenge we are facing was brought into sharp focus by findings from a recent small-scale follow-up study in Germany of confirmed but non-hospitalised patients in which 80% of subjects had cardiovascular (CMR revealed) abnormalities and 60% had evidence of ongoing heart inflammation [1]. Findings such as these should also surely flag up the need to proceed with extreme caution into challenge studies with real virus (which have been reported widely today to be in the planning stage), when the longer term consequences of even mildly symptomatic patients are so difficult to predict.
Reference:
1. Puntmann VO, Carerj ML, Wieters I, et al. Outcomes of Cardiovascular Magnetic Resonance Imaging in Patients Recently Recovered From Coronavirus Disease 2019 (COVID-19). JAMA Cardiol. Published online July 27, 2020. doi:10.1001/jamacardio.2020.3557.
Competing interests: No competing interests