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COVID-19 and Long Covid:

Understanding Long COVID

December 19, 2020

For updates on COVID-19 as it relates to autoimmune disease, check out our evolving timeline: COVID-19 News and Research Updates


What Is "Long COVID"?

Although there is no firm agreement in the medical world, long COVID develops when COVID-19 patients find that their symptoms persist after the normal period of recovery. These patients may also experience new and puzzling symptoms after they are confirmed COVID negative.

You may have long COVID or be a “long hauler” if you had confirmed or suspected COVID-19, and you have not fully recovered or returned to your previous state of health—for weeks or months after the infection itself has gone. Other terms used are post-COVID-19 syndrome and chronic COVID-19; however, they “risk delegitimizing suffering… and that will make it harder for people to access care,” the authors of a Nature editorial state (1). In fact, among the difficulties long COVID patients face is credibility. Patients may feel dismissed by their health care practitioner if they still have lingering unexplainable symptoms post-recovery. With still developing knowledge of COVID-19’s long-term ramifications, both patients are feeling their way forward.

The varying lengths of time that patients experience lingering symptoms are debated. A King’s College Study states that long COVID is the presence of continued symptoms for over one month (2), while entities in the United Kingdom, such as The National Institute for Health & Care Excellence (NICE), have determined the time period to be more than three months (4). Any of the above estimates is in stark contrast with the fact that a typical coronavirus infection resolves after two weeks.

Four Categories of Long-Term Effects

Long-term effects from COVID-19 fall into several categories, making it difficult to identify when the normal recovery period ends and long COVID begins.

  1. Post-intensive care syndrome (4, 5)
  2. Organ damage (including heart, lung, brain, and kidneys) from COVID-19-related pneumonia, lung inflammation, and other complications (4, 5, 67, 8)
  3. Ongoing symptomatic COVID-19, which the U.K.’s NICE defines as continued symptoms for 4 to 12 weeks (4)
  4. Post-COVID-19 syndrome, post-infectious fatigue syndrome, or post-viral syndrome – generally known as long COVID

You may see the term “long COVID” as referring to all or some of these effects; however, it has become more synonymous with the mysterious lingering symptoms—ones unrelated to organ damage—experienced by both severely and mildly ill patients alike.

Common Long COVID Symptoms

A person experiencing long COVID has persistent symptoms despite a negative coronavirus test after the normal recovery period from COVID-19. Symptoms can come and go, change over time, and affect any system in the body (4).

For many, despite fatigue, brain fog, shortness of breath, and other debilitating symptoms, routine lab work will show zero red flags. This makes the search for answers frustrating and confusing for both doctor and patient.

According to patient studies (68), the most common symptoms reported include:

  • Extreme fatigue
  • Body aches
  • Shortness of breath
  • Difficulty concentrating (brain fog)
  • Trouble sleeping
  • Headaches

The CDC includes joint pain and chest pain on their list, as well as other reported symptoms like depression, muscle pain, intermittent fever, and rapid heartbeat (9).

Post-Exertional Malaise & ME/CFS

One other common occurrence in people with long COVID is post-exertional malaise (PEM), “where even mild physical exertion can cause a severe symptom flare-up for days,” says Dr. Putrino at the Mount Sinai Hospital in New York (7). The Solve ME/CFS Initiative notes that exertion in PEM also means cognitive or emotional, not just physical symptoms (10). Around 90% of Dr. Putrino’s long COVID patients are living with PEM.

PEM is also a distinctive feature of myalgic encephalomyelitis or chronic fatigue syndrome (ME/CFS). Dr. Anthony Fauci, Director of the National Institute of Allergy and Infectious Diseases (NIAID) at the National Institutes of Health (NIH)  stated that long COVID symptoms are “strikingly similar” to those of ME/CFS (11), indicating that some cases of long COVID may actually be ME/CFS itself.

The mounting information available on ME/CFS and PEM is coming in handy regarding long COVID patients, as the discussion surrounding treatment is an equally delicate matter.

One suggested treatment for both conditions has been graded exercise therapy (GET); however, it is becoming well-known that this therapy can be dangerous for many patients experiencing PEM. Despite its seemingly gentle approach by incrementally increasing activity overtime, “GET can repeatedly push a patient to the point where the PEM response is triggered, resulting in an overall (possibly permanent) worsening of symptoms” (10) according to the Solve ME/CFS Initiative. Patient advocate groups like the ME Action Network and the Solve ME/CFS Initiative firmly state that it can be extremely damaging for ME/CFS patients and warn against its usage.

The Centers for Disease Control and Prevention (CDC) has removed GET from its list of recommended treatments (21), and the National Institute for Health and Care Excellence (NICE) in the UK is reviewing the evidence for this therapy in response to mounting concerns. NICE also states that the clinical guidelines on GET “…only apply to people with a diagnosis of ME/CFS as part of specialist care…” and that the guidelines “…should be part of an individualised, person-centred programme of care, with GET only recommended for people with mild to moderate symptoms…” (22).

PEM has different triggers and outcomes for each person, thus requiring a high level of awareness and personalized strategies. This is why it is crucial for doctors to assess needs on an individual basis and for patients to learn about the treatments and recommendations provided to them.

For individuals with PEM, it is widely agreed that a safe way to reduce potential symptoms, flare-ups, or “crashes” is pacing. As the Solve ME/CFS Initiative explains, this means adopting specific strategies that help you “remain as active as your limited energy allows while taking proactive steps to avoid reaching your personal overexertion point and triggering the PEM response” (10). It is all about listening to your body and getting to know its boundaries, and using that information to make decisions about daily activities. As an accompaniment to the strategy of pacing, doctors and researchers from the Stanford ME/CFS Initiative have created an in-depth PEM Avoidance Toolkit with tracking sheets and detailed information on causes, barriers, and strategies to help people manage their conditions on a daily basis.

Long COVID & Autoimmune Disease

The fact that ME/CFS can be triggered by an infection like coronavirus is not necessarily a new phenomenon.

Pathogens like the Parvovirus B19, Rubella virus, and Epstein-Barr virus (EBV) have been implicated in the development of autoimmune diseases (13) as well as post-infectious or post-viral disease syndromes linked to Lyme disease, mononucleosis, and the West Nile virus (WNV) (3). Glandular fever, which usually stems from an EBV infection, seems to trigger ME/CFS in some people.

Other conditions that may develop post-COVID are Guillain Barré syndrome, acute disseminated encephalomyelitis (ADEM), systemic lupus erythematosus (SLE), and other autoimmune diseases and inflammatory illnesses (13). One preliminary investigation studying autoreactivity and COVID-19 found a link between severe SARS CoV-2 infection and “the presence of autoantibodies against multiple targets,” indicating that an antiviral immune response in the case of COVID-19 prompts the production of autoreactive antibodies. Many features of this response are “reminiscent of SLE pathogenic autoreactivity” (14). Although there is quite clearly a link, neither the precise etiology nor the prevalence of these coronavirus-related autoimmune diseases is widely known.

How Many People Experience Symptoms and for How Long?

A King’s College Study from October 2020 analyzed data from 4,182 users of the COVID Symptom Study app. The article is not yet peer-reviewed, but nonetheless offers significant insight into what sufferers of long COVID experience.

According to researchers, “one in 20 people with COVID-19 are likely to suffer symptoms for 8 weeks or more” (2). They also learned that around 10% of people have lingering symptoms after 3 weeks and 5% are unwell for months post-COVID (6, 15).

A CDC study reported that 35% of symptomatic COVID-19 patients still were not back to their original state of health 2-3 weeks after their positive tests. Additionally, one in five respondents were aged 18-34 and did not have underlying health conditions (16).

Who Is At-Risk for Long COVID?

Anyone can develop long COVID, no matter the age or if their case of COVID-19 is mild or not, though there are factors that put someone at higher risk.

Risk factors include:

  • Severe COVID-19 cases (6)
  • Adults over 50 (6)
  • *Female sex (18)
  • Individuals with 2 or 3 chronic conditions (6)

*Another connection between long COVID and autoimmune disease is that women are at greater risk to develop these conditions with women 50% more likely to suffer from long COVID than men,” according to a COVID Symptom Study app analysis by King’s College (18). While the reason is still being explored, experts like Professor Tim Spector (one of the researchers leading the COVID Symptom Study App analysis at King’s College), speculates that it may have something to do with gender differences in immune response (19).

Why Are Patient-Reported Experiences Important?

Patient-led research and analyses of patient-reported experiences are increasingly common in the age of coronavirus. Of course, bench science remains essential, but this new strain of coronavirus has brought research to a frenzied level as the world tries to stop its devastation. Therefore, patient-led research can provide clues about early warning signs of long COVID as well as how symptoms vary and fluctuate depending on a variety of factors, including age and underlying condition. Medical professionals and public health officials can use this information to explore early treatment options and ensure people are getting the care they need.

Data collection and aggregation are vitally important to the discovery of treatments for long COVID. The effort to gather information is essential for ongoing research to find out how to treat, mitigate, or even cure long COVID. Since medical research is dealing with a newly emergent disease, very little data exists. All research entities need to compile as much data as possible. In an ideal world, a global consortium of data would benefit scientific discovery not only on COVID-19 but also on long COVID.

If you or a loved one have long COVID, consider getting involved by reporting symptoms and other information about your experience through any one of these sources:

Supporting Long Haulers

If you or a loved one is experiencing long COVID, Survivor Corps offers a helpful list of Post-COVID Care Centers (PCCC) across the U.S., as well as in Canada and India. These centers focus on multidisciplinary and comprehensive care. In the U.K., there are multidisciplinary clinics opening in various regions throughout England, funded by NHS England. Also offered is an online rehab service called Your COVID Recovery, with resources for managing symptoms as well as an on-demand service providing consultations with medical professionals.

For added support and information, connect with fellow long haulers through these groups:

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  1. Article Footnotes
    1. “Long COVID: let patients help define long-lasting COVID symptoms.” (2020). Nature, 586, 170. doi: https://doi.org/10.1038/d41586-020-02796-2

    2. Sudre, C., Steves, C., & Spector, T. (2020). New research identifies those most at risk from long COVID. King’s College London. 

    3. Amitay, O., & Komaroff, A.L. (2020). We know too little about Covid-19 ‘long-haulers.’ We need a comprehensive study. The Guardian.

    4. Tatum, M. (2020). “I could barely function’ – the devastating effects of long COVID.” The Pharmaceutical Journal, 305(7943). 

    5. Baillie, K.U. (2020). Long-term effects of COVID-19 and support to cope. Medical XPress.

    6. Komaroff, A. (2020). The tragedy of long COVID. Harvard Health Publishing. 

    7. McGrath, S. (2020). Understanding long covid: a shortcut to solving ME/CFS? MECFS Research Review.

    8. Kelland, K. (2020). This study could explain why some patients suffer ‘long COVID.’ World Economic Forum.

    9. Long-term effects of COVID-19.” (2020). Center of Disease Control and Prevention.

    10. Management and Treatment of ME/CFS.” The Solve ME/CFA Initiative. 

    11. Geddes, L. (2020). Long Covid: overlap emerges with ME – including debate over treatment. The Guardian. 

    12. Ehrenfeld, M., Tincani, A., Andreoli, L., Cattalini, M., Greenbaum, A., Kanduc, D., Alijotas-Reig, J., Zinserling, V., Semenova, N., Amital, H., & Shoenfeld, Y. (2020). Covid-19 and autoimmunity. Autoimmunity reviews, 19(8), 102597. doi:10.1016/j.autrev.2020.102597

    13. Cañas C. A. (2020). The triggering of post-COVID-19 autoimmunity phenomena could be associated with both transient immunosuppression and an inappropriate form of immune reconstitution in susceptible individuals. Medical hypotheses, 145, 110345. doi: 10.1016/j.mehy.2020.110345

    14. Woodruff, M.C., Ramonell, R.P., Lee, F.E-H., & Sanz, I. (2020). Clinically identifiable autoreactivity is common in severe SARS-CoV-2 Infection. MedRxiV. doi: https://doi.org/10.1101/2020.10.21.20216192

    15. Kelland, K. (2020). What is ‘Long COVID’ and what parts of the body does it affect? World Economic Forum.

    16. Tenforde, M. W., Kim, S. S., Lindsell, C. J., Billig Rose, E., Shapiro, N. I., Files, D. C., Gibbs, K. W., Erickson, H. L., Steingrub, J. S., Smithline, H. A., Gong, M. N., Aboodi, M. S., Exline, M. C., Henning, D. J., Wilson, J. G., Khan, A., Qadir, N., Brown, S. M., Peltan, I. D., Rice, T. W., Hager, D.N., Ginde, A.A., Stubblefield, W.B., Patel, M.M., Self, W.H., Feldstein, L.R., & IVY Network Investigators. (2020). Symptom Duration and Risk Factors for Delayed Return to Usual Health Among Outpatients with COVID-19 in a Multistate Health Care Systems Network – United States, March-June 2020. MMWR. Morbidity and mortality weekly report, 69(30), 993–998. doi: 10.15585/mmwr.mm6930e1

    17. Couzin-Frankel, J. (2020). The long haul. Science, 369(6504), 614-617. doi: 10.1126/science.369.6504.614

    18. Sudre, C., Murray, B., Varsavsky, T., Graham, M., Penfold, R., Bowyer, R., Pujol, J., Klaser, K., Antonelli, M., Canas, L., Molteni, E., Modat, M., Cardoso, M., May, A., Ganesh, S., Davies, R., Nguyen, L., Drew, D., Astley, C., Joshi, A., Merino, J., Tsereteli, N., Fall, T., Gomez, M., Duncan, E., Menni, C., Williams, F., Franks, P., Chan, A., Wolf, J., Ourselin, S., Spector, T., Steves, C. (2020). Attributes and predictors of Long-COVID: analysis of COVID cases and their symptoms collected by the Covid Symptoms Study App. MedRxiV. doi: https://doi.org/10.1101/2020.10.19.20214494

    19. Geddes, L. (2020). Women aged 50-60 at greatest risk of ‘long Covid’, experts suggestThe Guardian.

    20. Facing up to long COVID.” (2020). The Lancet, 396(10266), 1891. 

    21. #MeAction. (2020). Graded exercise therapy not recommended for post-COVID fatigue, say NICE. The Myalgic Encephalomyelitis Action Network.

    22. Statement about graded exercise therapy in the context of COVID-19.” (2020). National Institute for Health and Care Excellence.