Long Covid epidemiology (prevalence, incidence, recovery rates)

[ME/CFS Skeptic]

moved thread

The long covid groups seem to believe that long covid is often associated with mild initial disease and not having antibodies on tests.

Ok, but most of these studies are based on confirmed PCR tests which if I understand correctly require virus particles, not necessarily antibodies.

On Twitter someone pointed me to this Danish preprint which found that 16% of patients reported fatigue and 13% concentration difficulties 12 weeks after COVID-19 infection. Acute and persistent symptoms in non-hospitalized PCR-confirmed COVID-19 patients (medrxiv.org)

 

[rogerblack]

The number of people in the UK with severe post-covid fatigue right now likely exceeds the generally accepted ~200K number for those with CFS. If they are in fact caused by the same pathology, 'our' numbers have just doubled.

At 18 weeks after infection, 12% of the 15+M infected in the UK with covid were still suffering symptoms. This figure only dropped 2% from the 12th week. #mecfs #longcovid The evidence some may remain unwell longterm is clear. 200K have severe day-day difficulties.
I think it's reasonable to say that at the very least those 200K would meet CFS criteria.

https://www.ons.gov.uk/peoplepopula...coronaviruscovid19infectionintheuk/1april2021

The end of this curve is hideously flat.

 

[ME/CFS Skeptic]

The evidence some may remain unwell longterm is clear.

I'm still waiting for the first study that appropriately selected COVID-patients and a control group, followed them up for a long enough time (6 months or longer) and that used a stringent threshold for disability (for example ME/CFS criteria), not just how many people report symptoms.

I think it's reasonable to say that at the very least those 200K would meet CFS criteria.

CFS criteria such as Fukuda are pretty stringent - prevalence studies suggest that most people with unexplained fatigue symptoms do not meet them.

 

[Simon M]

The ONS survey asked about impact on daily activities: no impact, limited a little or limited a lot.

Only one in five of the 14% of people who had at least one symptom at 12 weeks (which gave the headline figure) said the daily activities were limited a lot.

So, that works out at 3% of people with enduring symptoms that limits their daily activities a lot at 12 weeks. I think that works out in the tens of thousands. Still a lot.

But the number will be lower at six months (as the curve shows). And a good chunk of those will have problems e.g. due to organ damage or post-intensive care issues.

I still think this is the best data we have because it’s a fairly large And relatively representative survey.

But we still have a long way to go before we know how many people in the UK have long Covid, let alone if/how many of those have ME/CFS.

 

[Esther12]

So, that works out at 3% of people with enduring symptoms that limits their daily activities a lot at 12 weeks. I think that works out in the tens of thousands. Still a lot.

I hadn't thought that through. That's actually quite a bit lower than would be expected for glandular fever.

 

[Peter T]

I hadn't thought that through. That's actually quite a bit lower than would be expected for glandular fever.

Interesting that previously there was the idea that other SARS virus related epidemics resulted in relatively high percentages of people developing ME, higher than you would expect from EBV infections.

I forget my source, but using one set of figures relating to a previous SARS epidemic, a very very approximate ‘back of a fag packet’ calculation I did at the start of the year left me expecting a UK doubling in cases of ME about now. Though obviously not fun for those that do get persistent problems hopefully Covid-19 is resulting in fewer cases of ME than might have been expected. It is still early to draw firm conclusions about the actual figures, but given the sheer size of the pandemic globally this will still be a lot of people.

Over the course of my ME I have been conscious that I have been very lucky to have been where and when I am. I suspect that had I not had safety nets that prevented homelessness or starvation, I would have died of an adventitious infection or other disease or in an accident relatively early in the course of my ME. How do we start planning for those with long Covid and related conditions in situations where there are few or no safety nets?

 

[arewenearlythereyet]

I thought the age prevalence was interesting but the gender split seems quite different to PWME when you look at the proportions?

The prevalence rate of self-reported long COVID was greatest among people aged 35 to 49 years or 50 to 69 years (2.5% and 2.4% respectively). The rate was statistically significantly higher in all adult age groups than in those aged 2 to 11 years or 12 to 16 years (Figure 2). The prevalence rate was statistically significantly higher in females (1.9%) than in males (1.5%).

 

[arewenearlythereyet]

And if you look at the symptoms for 12 weeks they are quite general and not unlike ME but also not quite the same profile ....no cognitive, gut issues disruptive sleep etc I suspect that might be an artifice of the questions asked though/lack of responses/ability to articulate?

The most prevalent self-reported symptoms that persisted for at least 12 weeks post-infection were the same as those experienced at 5 weeks: fatigue (8.3%), headache (7.2%), cough (7.0%), and myalgia (5.6%). These estimates should be interpreted with caution because of low numbers of study participants still reporting individual symptoms at 12 weeks. It was not possible to reliably estimate 12-week prevalence rates for individual symptoms in the control group for the same reason. Full results for all 12 symptoms included in the analysis can be found in the accompanying datasets.

There is some coverage here, although as I mentioned in a previous post on another thread the bbc at least don’t seem to be giving much credence or coverage to this “news”

https://www.bbc.co.uk/news/health-56601911

 

[Simon M]

How many have long covid? And how many have something with symptoms as severe as mecfs?

So, that works out at 3% of people with enduring symptoms that limits their daily activities a lot at 12 weeks. I think that works out in the tens of thousands. Still a lot.

I hadn't thought that through. That's actually quite a bit lower than would be expected for glandular fever.

Yes, seems to be a lot less than you'd expect for glandular fever, I think that typically around 10% with GF meet CFS criteria at six months?

However, there is a major caveat. Like a lot of "Long Covid" studies, these cohort studies only ask about the original Covid symptoms and not, for instance, cognitive problems/brain fog and post exertional malaise. If you have these other symptoms, and they were the cause of your daily activities being "limited a lot", then you wouldn't show up in the 3% figure I quoted.

For this Coronavirus Infection Survey (CIS), the recorded symptoms listed in order of frequency at 12 wqeeks were (with frequency in brackets for a few):

Fatigue (61%), headache, cough, myalgia (41%), sore throat, loss of smell, loss of taste, shortness of breath, nausea/vomiting, diarrhoea, abdominal pain (11%), fever (0%).​

Other definitions of long covid
a German study that also only measured Covid symptoms asked people if they felt they had recovered and 96% said yes, even though, while follow-up time varied a lot, the typical follow-up time would only have been seven weeks.

Both this German study and the CIS study run by ONS have the advantage that they should be fairly representative. The ONS sample is constructed that way. The German sample used consecutive positive cases reported.

"Other Long Covid prevalence studies are available".

[CIS Sample 21,622 participants who tested positive for coronavirus, of whom 2,962 had at least one coronavirus symptom continuously to 12 weeks.]

 

[mango]

Symptoms and Functional Impairment Assessed 8 Months After Mild COVID-19 Among Health Care Workers

https://jamanetwork.com/journals/jama/article-abstract/2778528?resultClick=1

"Approximately 80% of hospitalized patients with COVID-19 report persistent symptoms several months after infection onset.1,2 However, knowledge of long-term outcomes among individuals with mild COVID-19 is scarce, and prevalence data are hampered by selection bias and suboptimal control groups.3,4 This cohort study investigated COVID-19–related long-term symptoms in health care professionals."

Ny studie: Långtidsbesvären efter mild covid kartlagda
https://www.svt.se/nyheter/inrikes/ny-studie-langtidsbesvaren-efter-mild-covid-kartlagda

Google Translate, English

New study: Long-term problems after mild covid mapped

Every tenth hospital employee has long-term problems left after eight months - despite the fact that they only became mildly ill with covid-19. This is shown by a large study from Danderyd Hospital and Karolinska Institutet [in Sweden]. Loss of smell and taste, fatigue and respiratory effects are the most common ailments. However, the researchers did not see an increased incidence of long-term cognitive problems, palpitations or long-term fever. [...]

One in four study participants had symptoms for at least two months after they became ill. One in ten had symptoms for at least eight months and stated that the problems had a negative effect on them at work, socially and at home. [...]

- It is important that the public knows that even mild covid can affect you for quite some time and that they can affect your quality of life negatively. We must keep the infection rates down, says Charlotte Thålin, who is a specialist doctor and responsible researcher for the COMMUNITY study. [...]

The Community study

The researchers have followed more than 2,000 employees at Danderyd Hospital since last spring. The study participants gave blood samples for immunity studies and answered a questionnaire about the presence of long-term problems. Participants have also been asked to estimate how the problems affect them at work, socially and at home.

The researchers compared those who had antibodies in the spring of 2020, with a control group of employees who did not fall ill with covid-19 during the year.

The sub-study on long-term covid is published in the scientific journal JAMA: Symptoms and functional impairment assessed 8 months after mild COVID-19.

The study is run by Danderyd Hospital and Karolinska Institutet, in close collaboration with KTH, SciLifeLab, Uppsala University and the Swedish Public Health Agency.

 

[rvallee]

Peer reviews performed by people seemingly not aware of their own surroundings is a massive problem. When experts make blatantly ignorant assertions with high confidence, you know there are serious fundamental flaws in the system, the kind that take decades to fester and grow out of all reasonable proportions.

Frankly at this point "peer-reviewed" has pretty much lost all meaning, it's clear that the process is very arbitrary, and on some issues it is fully dependent on the individual's beliefs and opinions, as much as their actual expert knowledge, if not more.

 

[rvallee]

Symptoms and Functional Impairment Assessed 8 Months After Mild COVID-19 Among Health Care Workers

https://jamanetwork.com/journals/jama/article-abstract/2778528?resultClick=1

"Approximately 80% of hospitalized patients with COVID-19 report persistent symptoms several months after infection onset.1,2 However, knowledge of long-term outcomes among individuals with mild COVID-19 is scarce, and prevalence data are hampered by selection bias and suboptimal control groups.3,4 This cohort study investigated COVID-19–related long-term symptoms in health care professionals."

Ny studie: Långtidsbesvären efter mild covid kartlagda
https://www.svt.se/nyheter/inrikes/ny-studie-langtidsbesvaren-efter-mild-covid-kartlagda

Google Translate, English

However, the researchers did not see an increased incidence of long-term cognitive problems

It's one of the most commonly reported problem. And frankly palpitations and low-grade fever are also pretty common. That they not see something that is obviously there suggests significant problems in their process. Let me guess, they used the severe dementia test again?

 

[mango]

Moved post

According to an investigation done by Sveriges Radio Ekot (news programme by Sweden's national publicly funded radio broadcaster), the first national review ever, the number of people in Sweden who has been diagnosed with post covid/long covid so far is 16 000.

The National Board of Health and Welfare says the figure means we will have to live with the consequences of Covid for a long time to come.

At the same time, the agency says that in the group diagnosed there are both those who recover quickly on their own, and those who have severe problems, so the figure is difficult to evaluate.

16 000 svenskar har fått diagnosen postcovid
https://sverigesradio.se/artikel/16-000-svenskar-har-fatt-diagnosen-postcovid

Så många har postcovid
https://sverigesradio.se/artikel/sa-manga-har-postcovid

Comments by the Swedish Covid Association:

Let's talk the credibility of the numbers from @socialstyrelsen. If this were true, about 160 000 would have had Covid in Sweden. [mango: according to the Public Health Authority's official statistics, the number is curently 1 007 792...]

The statistics are entirely dependent on the diagnoses being made, but prejudice and distrust are widespread in the medical profession, as we have long warned

While research points to organ damage, severe disability and increased mortality (among the 10% or more who are affected), doctors engage in bias and pseudoscience, blaming patients

Social media is often cited as the cause. Despite the fact that the problem is global and far beyond these circles.

In fact, social media and the patient movements that have sprung up there have played a crucial role in raising the alarm about this public health crisis, according to the WHO and others.

We have long stressed that Sweden must stop excluding #longcovid from public health (@Folkhalsomynd doesn't even work with the issue) and produce credible statistics.

Translated with www.DeepL.com/Translator (free version)

The Swedish Covid Association and Läkare till läkare (Doctor to Doctor) wrote an opinion piece about this a month ago, highlighting the problems related to the inaction and the lack of data, contrasting it to the UK approach etc:

Debatt: Brådskande vård försenas när statistik om långtidscovid saknas
https://www.altinget.se/vard/artike...rsenas-nar-statistik-om-laangtidscovid-saknas

"Immunitetsexperimentets offer" has blogged about the 16 000 news and SFAM's webinars here:
https://ensamladbedomning.blogspot.com/2021/05/regeringen-stodkoper-konst-inte-bara.html

In the UK, studies have found that about 10% of those infected suffer from long covid. This would mean that at least 100 000 people are affected in Sweden. The number is probably even higher, as the estimated number of unknown cases of infected people is likely to be high.

(As a comparison, based on a prevalence rate of 0.4%, the estimated number of people in Sweden living with ME is 40 000. The number of people in Sweden who have been diagnosed with ME is unknown.)

 

[Wyva]

Moved post
Guardian article: Why are women more prone to long Covid?

The explanation mostly comes from Akiko Iwasaki, and a more robust immune response, T cell activity, autoimmunity are mentioned but also that these kind of diseases are taken much less seriously due to the fact that women are disproportionately affected. ME/CFS and chronic Lyme get mentioned a couple of times for comparison and that these diseases can also benefit from long covid research.

Many scientists studying long Covid believe that, in a proportion of cases, the virus may have triggered an autoimmune disease, causing elements of the immune system to produce self-directed antibodies known as autoantibodies, which attack the body’s own organs. Since December last year, Iwasaki and others have published studies that have identified elevated levels of more than 100 different autoantibodies in Covid-19 patients, directed against a range of tissues from the lining of blood vessels to the brain. While the level of some of these autoantibodies subsided naturally over time, others lingered. Iwasaki believes that if these self-directed antibodies remain in the blood of long Covid patients over the course of many months, it could explain many of the common symptoms, from cognitive dysfunction to clots, and dysautonomia – a condition where patients experience an uncomfortable and rapid increase in heartbeat when attempting any kind of activity.​

https://www.theguardian.com/society/2021/jun/13/why-are-women-more-prone-to-long-covid

 

[Arnie Pye]

Merged thread
Mostly good article, worth reading, several mentions of ME/CFS.

https://www.theguardian.com/society/2021/jun/13/why-are-women-more-prone-to-long-covid

While men over 50 tend to suffer the most acute symptoms of coronavirus, women who get long Covid outnumber men by as much as four to one

In June 2020, as the first reports of long Covid began to filter through the medical community, doctors attempting to grapple with this mysterious malaise began to notice an unusual trend. While acute cases of Covid-19 – particularly those hospitalised with the disease – tended to be mostly male and over 50, long Covid sufferers were, by contrast, both relatively young and overwhelmingly female.

Early reports of long Covid at a Paris hospital between May and July 2020 suggested that the average age was around 40, and women afflicted by the longer-term effects of Covid-19 outnumbered men by four to one.

Over the past 12 months, a similar gender skew has become apparent around the world. From long Covid patients monitored by hospitals in Bangladesh and Russia to the Covid Symptom Tracker app, from the UK-wide Phosp-Covid study assessing the longer-term impact of Covid-19, to the medical notes of specialist post-Covid care clinics across both the US and the UK, a picture has steadily emerged of young to middle-aged women being disproportionately vulnerable.

 

[Peter T]

Unfortunately not as balanced an article in today’s London Times,

Why is Britain now the capital of Long Covid?
see https://www.thetimes.co.uk/article/...FUd4nM_eL2-X_5D2Qbr2nFCMVdy2K1P09EMmGSdF1ygFs
https://www.thetimes.co.uk/article/...FUd4nM_eL2-X_5D2Qbr2nFCMVdy2K1P09EMmGSdF1ygFs
Sorry it is behind a paywall. It focuses on the biomedical/psychosomatic debate and gives several uncritical column inches to Jeremy Devine’s (Psychiatric registrar at McMaster University in Canada) recent ghastly article in the Wall Street Journal, we discussed here.

Makes no mention of ME/CFS or PEM and implies the balanced response is to assume Long Covid has a significant psychiatric component. I don’t think it deserves a thread of its own.

 

[Adrian]

Sorry it is behind a paywall. It focuses on the biomedical/psychosomatic debate and gives several uncritical column inches to Jeremy Devine’s (Psychiatric registrar at McMaster University in Canada) recent ghastly article in the Wall Street Journal, we discussed here.

I really think this debate is missing the point it should be about good and bad science - i.e. how theories are formed and tested. When we talk about theories such as the psychosomatic ones it should be up to the proponants to demonstrate evidence that makes them worth testing (and they have been working in the area for a long time)>

 

[shak8]

I like the Guardian article. It has some immunology I was unaware of.

(https://www.theguardian.com/society/2021/jun/13/why-are-women-more-prone-to-long-covid).

 

[chrisb]

I really think this debate is missing the point it should be about good and bad science - i.e. how theories are formed and tested. When we talk about theories such as the psychosomatic ones it should be up to the proponants to demonstrate evidence that makes them worth testing (and they have been working in the area for a long time)>

Yes, but before we can assess the quality of the science we have first to ascertain what the purported science is. Now that we know that McMaster was working with a "Behavioural Medicine Unit" at St Joseph's Hospital Hamilton from 1975 and that that work was used in the development of the illness behaviour model, we have better ways of critiquing work coming out of that university. At least we know where to start looking.

 

[Jonathan Edwards]

I like the Guardian article. It has some immunology I was unaware of.

(https://www.theguardian.com/society/2021/jun/13/why-are-women-more-prone-to-long-covid).

I was 'unaware' of some of that immunology as an immunologist. I am not that impressed by Cox's grasp of the subject.