About Long COVID And The Overlap With Myalgic Encephalomyelitis (ME) In A Nutshell

Long COVID, which goes by many names, occurs worldwide and refers to any of more than 100 symptoms that according to the World Health Organization definition persist, recur or first appear three months after an infection, or a suspected infection, with SARS-CoV-2. These symptoms can affect any part of the body and can persist for weeks, months or longer. The five most common of these symptoms, according to the September 2022 brief by the Ontario Covid-19 Science Advisory Table are fatigue, memory deficits, shortness of breath, sleep problems and joint pain. A patient-led study done in 2021, found a similar list. Their top ten symptoms persisting after 6 months were: fatigue, post-exertional malaise, brain fog (cognitive dysfunction), sensorimotor symptoms (e.g, dizziness, neuralgia, vibrating sensations), headaches, memory issues, insomnia, muscle aches, palpitations and shortness of breath.

The possible symptoms, symptom constellation/grouping and their severity vary from person to person. They can significantly reduce quality of life and can impair the ability to work and care for oneself. In other words, long COVID can be a disabling condition and it can result in complete reliance on others.

Statistics Canada data (October 2022) shows that almost 15% of Canadians who had Covid-19 experienced symptoms at least three months after their infection; that is, 1.4 million Canadians over the age of 18 or 4.6% of the population. Worldwide the estimates of those affected (while large) vary widely and this is a function of how little is known or agreed upon about the condition, including how it should be defined, causes, prevention and prognosis. Even so, the potential societal impact is substantial, in Ontario, across Canada and worldwide.

raw attention to further words from the Ontario Covid-19 Science Advisory Table brief (Quinn et al., 2022) wherein they note

…. [A] proactive and comprehensive strategy to manage the post COVID-19 condition needs to be developed by health systems and policy makers. This strategy should include substantial investments in research and health system resources to mitigate the long-term health, social, and economic impacts of the post COVID-19 condition in Ontario. p. 1

Federally in Canada attention is being paid to long COVID (calling it Post Covid-19 Condition or PCC) by the Chief Science Advisor who, in mid-December 2022, released recommendations to further information about the condition as well as deal with the impacts on the individual and society. Much more work is needed but the government and the Public Health Agency of Canada recognize that action is required.

What neither the Ontario Science Table nor the Chief Science Advisor note, and we want to underline, is the overlap between long COVID and the conditions for which CareNow Ontario advocates, the most obvious (but not only) of which is ME.

“People like me who were in the prime of their lives, were active workers, active parents and now are at home managing completely incapacitating symptoms and with a strong possibility they may never get better” Carrie Anna as quoted in Montreal CityNews

“This illness has taken so much from me. It’s taken my job, it’s taken my relationships with all of my clients and my family and my friends, my passions, my hobbies. I noticed that every single system in my body was being affected,” Kelli as quoted in CBC news.

“To shower in the morning I have to check I’ve got enough energy to wash my hair and deal with it afterwards. I often need to rest between showering/dressing/doing hair (Participant 10) Symptoms” https://onlinelibrary.wiley.com/doi/full/10.1111/hex.13602

The Bigger Picture

The Name


Who Gets Long Covid – A Brief Snapshot of What is Showing Up


Is There Help For Long Covid?

Clinical Management

Patient Safety — What about Exercise Therapy and Rehabilitation?

Self Management


Impact for the Economy, Health Systems and SocietyI

Overlap With ME - What Do We Know

Useful references and links

The Name

Long COVID is a name that was coined by the patient community and it is their preferred one, recognizing that it is a continuation of COVID-19, not somehow separate from it. There is a wide range of other terms being used to describe the same phenomena of health problems — continuing, recurring or new — experienced within a few months having COVID-19. These names include: long-haul COVID, post COVID-19 condition, chronic COVID, and post-acute sequelae of SARS-CoV-2 (PASC). The Public Health Agency of Canada (PHAC) and Health Canada use post Covid-19 condition (PCC, although they recognize long COVID as an alternate), while Public Health Ontario uses PASC. The multitude of names and definitions has the potential, as we have seen in other illnesses including ME, to confuse research. It is important in research, particularly that looking at disease mechanisms, to be clear that the subjects being researched all have the same condition otherwise conclusions drawn from the research may not be accurate.


There is no universal definition for long COVID (under any of the terms listed above).

The World Health Organization (WHO) defines post COVID-19 condition as:

“[…] occurring in individuals with a history of probable or confirmed SARS CoV-2 infection, usually 3 months from the onset of COVID-19 with symptoms and that last for at least 2 months and cannot be explained by an alternative diagnosis. Common symptoms include fatigue, shortness of breath, cognitive dysfunction but also others and generally have an impact on everyday functioning. Symptoms may be new onset following initial recovery from an acute COVID-19 episode or persist from the initial illness. Symptoms may also fluctuate or relapse over time.”

In addition to the WHO, the Ontario Covid-19 Science Advisory Table brief in Table 1 provides terminology and common clinical definitions from three other agencies: the Public Health Agency of Canada (PHAC), UK’s National Institute for Clinical Excellence (NICE), and the US Centres for Disease Control and Prevention.

Who gets Long Covid? – A Brief Snapshot of What is Showing

The short answer is that anyone infected with the SARS-CoV-2 virus can get long COVID including those who experienced mild symptoms.

Statistics Canada’s report shows that almost 15% of Canadians who had Covid-19 experienced symptoms at least three months after their infection; that is, 1.4 million Canadians over the age of 18 or 4.6% of the population. The percentage for the US with lingering symptoms three months after Covid-19 is similar at 19%, but given this slightly higher number, as well as a higher percentage of the US population who experienced Covid-19, there are 7.5% of the US population with long COVID symptoms.  [https://www.cdc.gov/nchs/covid19/pulse/long-covid.htm] In the UK it is 3.3% of the population (note, they are measuring symptoms continuing after 4 weeks).

It is becoming clearer that more women than men are affected. This is borne out by the Statistics Canada data showing a higher percentage of women (18.0%) reported prolonged symptoms compared with men (11.6%) and the same in the US and UK.

No significant differences by age group were found in the percentage of Canadian adults reporting prolonged symptoms. In the US and UK, the prevalence appears to be greatest in the 35-69 year age group.

Children can get long COVID and parents and providers should be on the lookout for this. Many of the early reports were that symptoms in children usually were mild but multisystem inflammatory syndrome in children MIS-C was possible. Early on in the pandemic, the possibility of long COVID in children was not fully established. This resulted in having difficulties obtaining recognition of their post COVID symptoms and obtaining educational accommodations. As a note, we continue to see the same situation with children in the ME community – difficulty having their symptoms recognized and then obtaining educational accommodation.

Certain populations may be more affected due to health inequities (e.g., sociodemographic, racial, rural, northern). Whether this is the case requires further research.


There are more than 100 possible symptoms and they can affect any part of the body, including the body as a whole. The symptoms come individually or in combination and they vary greatly as to how severe they are, or how often they occur (frequency and severity). A symptom description pictorial can be found on the NIH long COVID webpage.

The symptoms that are being seen most frequently in Canada are: fatigue including tiredness or loss of energy, coughing, shortness of breath (or difficulty breathing), difficulty thinking or concentrating (brain fog) and general weakness. These all appear on the CDC’s longer list of the symptoms most commonly reported:

General Symptoms
Respiratory and Heart Symptoms
Neurological Symptoms
Digestive Symptoms
Other Symptoms

Note: The CDC webpage also acknowledges that many of the symptoms are similar to those reported by people with ME and other poorly understood chronic illnesses that may occur after infections.

Long COVID is not the only medically related fallout from COVID-19. A complication of severe disease for those who were in the intensive care unit may be PICS (post-intensive care syndrome). As well, it is being recognized that simply having had COVID-19 is increasing the risk of developing other conditions including heart disease and diabetes.

Is there help for Long Covid?

Clinical Management

Long COVID is being dealt with as a new clinical entity and health care systems are working at creating tools and resources to support management. Some of these will be mentioned below. What is also being found is that it is challenging to address in the context of present medical uncertainties about the condition, as well as the complexities and multifaceted functional impairments that can result. What is known is that a multidisciplinary coordinated approach is needed. CareNow Ontario has continually championed the need for such an approach to address the complex illnesses it represents.

Following is a list of tools and resources that are presently available.

Patient Safety – What about Exercise Therapy and Rehabilitation?

We do want to make a specific note about this topic, urging caution for both patients and therapists.

The ME community, including patients and healthcare practitioners, shared valuable learnings and cautions from their own experiences with post-viral illnesses and post-exertional malaise with long COVID patients who struggled early on to find help with symptoms they developed in the aftermath of having COVID. Similar cautions, fortunately reflected in the WHO guidance, come from long Covid Physios, As they note, COVID rehabilitation should:

Self Management

Although it doesn’t take the place of medical care, self management strategies have proven very helpful for many chronic conditions. Seek out as much information as you can about your illness and about the steps you can take to monitor your health. Many of the suggestions made for myalgic encephalomyelitis, fibromyalgia and multiple chemical sensitivity will help here. Chronic Disease Self-Management programs are available across Ontario, including online and over the telephone, and may be useful. For information in Ontario, https://www.selfmanagementontario.ca/. More information about services in your area can be found through https://www.thehealthline.ca.

The British Columbia Provincial Health Services site has a wealth of patient resources in this area that may be helpful.

Caring for Someone with long COVID

Be aware that people with long COVID may need your assistance. People with long COVID will have differing needs. Some will be able to manage with only minimal assistance, others with more severe symptoms may need a lot of hands-on help.


It should go without saying that the best way to prevent long COVID is to not get infected with the virus in the first place. On the positive side, there is data to suggest that the combination of vaccination and emerging variants has resulted in less frequent long COVID. Regarding vaccination, the Ontario Science Advisory Table’s brief had this to say,

Overall, there appears to be some benefit of vaccination in preventing the development of the post COVID-19 condition when given before or after SARS-CoV-2 infection, and possibly after the development of the post COVID-19 condition. These findings support continued efforts to recommend vaccination against SARS-CoV-2. (Vaccination and the Post-Covid condition, p. 9)

Impact For The Economy, Health systems and Society

In a word, the impact is “huge” and is and will be felt worldwide across the economy and society. It is having an impact on the amount of health services people are using (as demonstrated in an Ontario-based study, on the workforce, and as one US report [https://nihrecord.nih.gov/2022/08/05/costs-long-covid-becoming-clear] noted on “disability and life expectancy rates and educational attainment in children.”

The economic impact of long COVID is substantial. In figures from the US (which include lost quality of life, lost earnings and higher spending on medical care) it has been suggested a possible impact of $3.7 trillion or 17% of pre-Covid US GDP. (Interestingly, many of the individual calculations are based on the similar impacts that have been seen in people with ME; in other words, the problem is the same – it is the scale that differs). Another economic calculation by the Brookings Institute, looking at the impact on the workforce [https://www.brookings.edu/research/new-data-shows-long-covid-is-keeping-as-many-as-4-million-people-out-of-work/, are similarly alarming. We do not have calculations from Canada but given the numbers affected, they too would be substantial.

As a UK study noted the impact is being disproportionately felt on people between the ages of 39-65, “an age group where people are usually fit and well, at the prime of their life, with the majority expected to be at work.” The same study recognized that it is increasingly being recognized that individuals are situated within a social context, and any impact is felt beyond the individual to their whole social network.

Overlap With Myalgic Encephalomyelitis (ME) – What Do We Know?

What seems to be clear is that there is a fairly large subset of people with long COVID who meet the diagnostic criteria for ME including length of time with symptoms (6 months), frequency and severity. Research in long COVID may point to answers for ME, and as we have already noted, lessons hard-learned from ME (about what works and doesn’t work in care) may be beneficial for people with long COVID.

It was hypothesized from early on in the Covid-19 pandemic that there would be a long term disease that looked a lot like ME. A systematic review from 2021 demonstrates striking clinical similarities between the two conditions. Similarity of symptoms between long COVID and ME and the impact that these symptoms have on people, including reduced function, mobility, exercise tolerance has continued to be shown. This however does not mean they are the same — that they have the same pathophysiological underpinnings, but it does raise suspicion.

There is still a lot to learn about both Long COVID and ME but we know that across a number of studies, including one from Germany and one from California it is being seen that around 45% of those with long COVID are also meeting ME case definitions.

Looking at this not from within long COVID but from the perspective of anyone who had Covid-19, a small study from Mexico found 13% of those ‘recovered’ from Covid-19 met the IOM criteria for ME six months later; very much in keeping with the findings from the so-called Dubbo studies regarding a post-infective fatigue syndrome that found in the order of 10% of those infected by a range of viruses remained sick months later.

For a very good summary of this whole area, refer to esteemed researcher and physician Anthony Komaroff’s October 2022 presentation, ME/CFS and Long COVID: Emerging Similarities and Why it Matters.

Useful Links and References

Government or agency websites


Government of Canada. Post COVID-19 condition (long COVID)). Date modified: 2022-10-20. [Accessed November 6, 2022]

Government of Canada. Frequency and impact of longer term symptoms following COVID-19 in Canadian adults. October 20-2022. [Accessed November 6, 2022] https://health-infobase.canada.ca/covid-19/post-covid-condition/

Office of the Chief Science Advisor. Post-COVID-19 Condition in Canada: What we know, what we don’t know and a framework for action. Pre-report December 14, 2022. [Accessed December 19, 2022] https://science.gc.ca/site/science/en/office-chief-science-advisor/initiatives-covid-19/post-covid-19-condition-canada-what-we-know-what-we-dont-know-and-framework-action-pre-reporta>

Statistics Canada. Long-term symptoms in Canadian Adults who tested positive for COVID-19 or suspected an infection, January 2020 to August 2022. The Daily. Released 2022-10-17. Accessed November 6, 2022 https://www150.statcan.gc.ca/n1/daily-quotidien/221017/dq221017b-eng.htm

United States

National Institutes of Health, Covid-19 Research. Long COVID. Accessed November 6, 2022. https://covid19.nih.gov/covid-19-topics/long-covid

US Centers for Disease Control and Prevention

For Patients: https://www.cdc.gov/coronavirus/2019-ncov/long-term-effects/index.html

For Providers: https://www.cdc.gov/coronavirus/2019-ncov/hcp/clinical-care/post-covid-conditions.html

National Center for Health Statistics, Long COVID:



United Kingdom

Office of National Statistics, United Kingdom, Prevalence of ongoing symptoms following Coronovirus (COVID-19) infection: 3 November 2022 https://www.ons.gov.uk/peoplepopulationandcommunity/healthandsocialcare/conditionsanddiseases/bulletins/prevalenceofongoingsymptomsfollowingcoronaviruscovid19infectionintheuk/latest

World Health Organization

World Health Organization Post-Covid-19 information https://www.who.int/publications/i/item/WHO-2019-nCoV-Post_COVID-19_condition-Clinical_case_definition-2021.1

Living Guidance for Clinical Management of COVID-19 https://www.who.int/teams/health-care-readiness/post-covid-19-condition

British Columbia, Provincial Health Services Authority

Health Professionals: Post-COVID Recovery Care http://www.phsa.ca/health-professionals/clinical-resources/post-covid-19-care

Health Info: Living with Post-Covid Symptoms http://www.phsa.ca/health-info/post-covid-19-care-recovery

Centre for Effective Practice (CEP)

The CEP a Canadian independent not-for-profit knowledge translation organization. Their COVID-19 Resource Centre was developed by the CEP in collaboration with the Department of Family Medicine at McMaster University, the Ontario College of Family Physicians and the Nurse Practitioners’ Association of Ontario.

The CEP digital tool for PASC available at https://tools.cep.health/tool/covid19/#long-term-symptoms-post-acute-sequelae-of-covid-19-pasc

Peer –reviewed literature

Davis HE, Assaf GS, McCorkell L, Wei H, Low RJ, Re’em Y, Redfield S, Austin JP, Akrami A. Characterizing long COVID in an international cohort: 7 months of symptoms and their impact. EClinicalMedicine. 2021 Aug;38:101019. doi: 10.1016/j.eclinm.2021.101019. Epub 2021 Jul 15. PMID: 34308300; PMCID: PMC8280690. https://pubmed.ncbi.nlm.nih.gov/34308300/

Décary S, Gaboury I, Poirier S, et al. Humility and Acceptance: Working Within Our Limits With Long COVID and Myalgic Encephalomyelitis/Chronic Fatigue Syndrome. J Orthop Sports Phys Ther. 2021;51(5):197-200. doi:10.2519/jospt.2021.0106 https://pubmed.ncbi.nlm.nih.gov/33930983/

Décary S, De Groote W, Arienti C, et al. Scoping review of rehabilitation care models for post COVID-19 condition. Bull World Health Organ. 2022;100(11):676-688. doi:10.2471/BLT.22.288105 https://pubmed.ncbi.nlm.nih.gov/36324552/

DeMars J, Brown DA, Angelidis I, Jones F, McGuire F, O’Brien KK, Oller D, Pemberton S, Tarrant R, Verduzco-Gutierrez M, Gross DP. What is Safe Long COVID Rehabilitation? J Occup Rehabil. 2022 Oct 31:1–4. doi: 10.1007/s10926-022-10075-2. Epub ahead of print. PMID: 36315323; PMCID: PMC9628454.https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9628454/

González-Hermosillo JA, Martínez-López JP, Carrillo-Lampón SA, et al. Post-Acute COVID-19 Symptoms, a Potential Link with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: A 6-Month Survey in a Mexican Cohort. Brain Sci. 2021;11(6):760. Published 2021 Jun 8. doi:10.3390/brainsci11060760 https://www.mdpi.com/2076-3425/11/6/760

Hickie I, Davenport T, Wakefield D, et al. Post-infective and chronic fatigue syndromes precipitated by viral and non-viral pathogens: prospective cohort study. BMJ. 2006;333(7568):575. doi:10.1136/bmj.38933.585764.AE https://pubmed.ncbi.nlm.nih.gov/16950834/

Kedor, C., Freitag, H., Meyer-Arndt, L. et al. A prospective observational study of post-COVID-19 chronic fatigue syndrome following the first pandemic wave in Germany and biomarkers associated with symptom severity. Nat Commun 13, 5104 (2022). https://doi.org/10.1038/s41467-022-32507-6

Komaroff AL, Bateman L. Will COVID-19 Lead to Myalgic Encephalomyelitis/Chronic Fatigue Syndrome?. Front Med (Lausanne). 2021;7:606824. Published 2021 Jan 18. doi:10.3389/fmed.2020.606824 https://pubmed.ncbi.nlm.nih.gov/33537329/]

Ledford H. How common is long COVID? Why studies give different answers. Nature. 2022;606(7916):852-853. doi:10.1038/d41586-022-01702-2

McNaughton CD, Austin PC, Sivaswamy A, Fang J, Abedel-Qadir H, Daneman N, Udell JA, Wodchis WP, Mostarac I, Lee DS, Atzema CL. Post-acute health care burden after SARS-CoV-2 infection: a retrospective cohort study. CMAJ Oct 2022, 194 (40) E1368-E1376. https://doi.org/10.1503/cmaj.220728

O’Hare AM, Vig EK, Iwashyna TJ, et al. Complexity and Challenges of the Clinical Diagnosis and Management of Long COVID. JAMA Netw Open. 2022;5(11):e2240332. doi:10.1001/jamanetworkopen.2022.40332 https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2798146

Pearson M, Singh P, Bartel H, Crawford P, Allsopp G. Creative Long Covid: A qualitative exploration of the experience of Long Covid through the medium of creative narratives [published online ahead of print, 2022 Sep 23]. Health Expect. 2022;10.1111/hex.13602. doi:10.1111/hex.13602

Pelà G, Goldoni M, Solinas E, Cavalli C, Tagliaferri S, Ranzieri S, Frizzelli A, Marchi L, Anselmo P, Mori A, Majori M, Aiello M, Corradi M , Chetta A. Sex-Related Differences in Long-COVID-19 Syndrome. Journal of Women’s Health. May 2022. 620-630. http://doi.org/10.1089/jwh.2021.0411

Quinn KL, Katz GM, Bobos P, et al. Understanding the post COVID-19 condition (long COVID) in adults and the expected burden for Ontario. Science Briefs of the Ontario COVID-19 Science Advisory Table. 2022;3(65) https://doi.org/10.47326/ocsat.2022.

Sukocheva OA, Maksoud R, Beeraka NM, et al. Analysis of post COVID-19 condition and its overlap with myalgic encephalomyelitis/chronic fatigue syndrome. J Adv Res. 2022;40:179-196. doi:10.1016/j.jare.2021.11.013 https://pubmed.ncbi.nlm.nih.gov/36100326/

Wong TL, Weitzer DJ. Long COVID and myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS)—A systemic review and comparison of clinical presentation and symptomatology. Medicina. 2021;57:418. doi: 10.3390/medicina57050418. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8145228/

Wurz A, Culos-Reed SN, Franklin K, DeMars J, Wrightson JG, Twomey R. “I feel like my body is broken”: exploring the experiences of people living with long COVID. Qual Life Res. 2022;31(12):3339-3354. doi:10.1007/s11136-022-03176-1 https://pubmed.ncbi.nlm.nih.gov/35816258/

Other useful sources including media

Backman, I. “Will Long COVID Research Provide Answers for poorly understood diseases like ME/CFS” Yale School of Medicine, News November 1, 2022. [Accessed November 6, 2022] https://medicine.yale.edu/news-article/will-long-covid-research-provide-answers-for-poorly-understood-ailments-like-chronic-fatigue/

Bonilla H., Quach, TC, Tiwari A, Bonilla AE, Miglis M, Yang P, Eggert L, Sharifi H, Horomanski A, Subramanian A, Smirnoff L, Simpson N, Halawi H, Sum-Ping O, Kalinowski A, Patel Z, Shafer R, Geng L. Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is common in post-acute sequelae of SARS-CoV-2 infection (PASC): Results from a post-COVID-19 multidisciplinary clinic. PREPRINT not peer reviewed https://www.medrxiv.org/content/10.1101/2022.08.03.22278363v1

Bock E. Costs of Long Covid Becoming Clear. NIH Record August 5, 2022 Vol. LXXIV, no. 16. https://nihrecord.nih.gov/2022/08/05/costs-long-covid-becoming-clear

Crawley M. “What 2 new studies reveal about long COVID in Canada.” CBC News. Health October 17, 2022. https://www.cbc.ca/news/health/long-covid-statistics-canada-1.6619649

Cutler DM. The Economic cost of Long COVID: An Update. July 16, 2022. https://scholar.harvard.edu/cutler/news/long-covid

Goldman B. “Parents of kids with long-COVID warn that children can develop severe symptoms. Dr. Anu Wadhwa says COVID-19 symptoms can start out mild then become pronounced.” White Coat, Black Art, September 5, 2021 https://www.cbc.ca/radio/whitecoat/parents-of-kids-with-long-covid-warn-that-children-can-develop-severe-symptoms-1.6156624

Ho S. “Long COVID could cost the economy trillions, experts predict” September 28, 2022 https://www.webmd.com/lung/news/20220928/long-covid-could-cost-economy-trillions-experts

Komaroff AL. Emerging Similarities ME/CFS and Long COVID: Why it Matters October 22, 2022. https://www.youtube.com/watch?v=AbVMvRS-a7Y Main Presentation or it can be accessed through https://www.massmecfs.org

Ontario College of Family Physicians. Post-COVID Condition (Long COVID). Tools and Resources [Accessed November 6, 2022] https://www.ontariofamilyphysicians.ca/tools-resources/covid-19-resources/long-covid

Patient Led Research Collaborative

Project Echo — Long Covid and Fatiguing Illness Recovery Program https://hsc.unm.edu/echo/partner-portal/echos-initiatives/long-covid-fatiguing-illness-recovery/