Long covid: probably worth avoiding—some considerations

Link post

I hear friends reasoning, “I’ll get covid eventually and long covid probably isn’t that bad; therefore it’s not worth much to avoid it now”. Here are some things informing my sense that that’s an error:

A. Really bad anecdotes aren’t hard to find.

I asked for people’s long-covid experiences on Twitter and got more than a hundred comments mostly full of truly awful stories, almost entirely from people I don’t know at all, presumably somehow brought via the active Long Covid community.

This is a bit hard to interpret as a datum, due to the intense selection effects involved, but my main inferences are:

  1. The bad tail gets very bad.

  2. This bad tail is less like a quantitative reduction in labor, and more like psychological torment, being very sleep deprived or brain damaged while dealing with a host of legitimately scary health problems (see below) than I had been picturing.

  3. The very bad part of the bad tail is not tiny. Like, if I requested lightning strike experiences, I don’t think I would get this kind of response.

See this for more heavily selected but still scary anecdotes about what bad cases can look like.

B. Bad anecdotes are common enough to show up in my vicinity.

Among this cascade of terrible stories is a response from one of the handful of people from my extended network who I already knew had had covid, Oxford machine learning professor Michael Osborne. I take this as strong evidence that that level of bad experience isn’t vanishingly rare, though he has been well for the last few months, so this is only direct evidence of this kind of thing happening for about two years.

Excerpts from his account:

(Another distant relative in my generation just told me that they have long covid, but I take that as much less evidence, since I only know about them having covid at all because they saw this long covid discussion.)

C. Rates of ambiguously-maybe-quite-bad symptoms seem very high, even for people who only had mild covid

This norwegian study, n = 70k, has, for mild cases (in a sample mixing people who had covid 1-6 months prior with people who had it 11-12 months prior):

  • 10.2% with fatigue (6.4% higher than control in the 11-12 months case),

  • 7.1% with poor memory (3.5% higher than previous control),

  • 9.2% with brain fog (5.3% higher than previous control).

  • 6.9% with shortness of breath (5.6% higher than previous control)

These numbers are for unvaccinated people; I’d maybe reduce them by a factor of two for being vaccinated, deferring to Matt Bell, who reasons, “A very recent report from the UK claims that full vaccination cuts the risk of lingering symptoms 28+ days after catching COVID by roughly half”.

This meta-analysis of 81 studies finds:

  • “Approximately 1 in 3 individuals experienced fatigue 12 or more weeks following COVID-19 diagnosis.”

  • “Approximately 1 in 5 individuals exhibited cognitive impairment 12 or more weeks following COVID-19 diagnosis.”

(Though I am told that lot of the studies involved might have been small-n, hospitalized, no control, so I’m not sure how they dealt with that.)

This survey suggests that among people with long covid (I think drawn from a support group), some especially undesirable symptoms are very: “88.0% of the total respondents (3310) experienced either cognitive dysfunction or memory loss (Figure 8).”

All of these symptoms come in degrees between slightly annoying and life-wrecking, making all of this hard to interpret. Maybe we can look at something more objective, like ‘can the person still do their job?’

D. It looks like a lot of people can no longer do their jobs

  • Katie Bach of Brookings argued a few days ago that an estimate of 1.1 million people out of work because of long covid is reasonable, out of 103 million working age Americans she estimated had had covid, i.e. a roughly 1% chance of being entirely out of work:

Metro_Bach_1_11_22_Figure-1(1)Metro_Bach_1_11_22_Figure-1(1)

Metro_Bach_1_11_22_Figure-2(1)Metro_Bach_1_11_22_Figure-2(1)

  • Washington post: “Hard data is not available and estimates vary widely, but based on published studies and their own experience treating patients, several medical specialists said 750,000 to 1.3 million patients likely remain so sick for extended periods that they can’t return to the workforce full time.”

  • This meta-analysis of 81 studies I mentioned earlier also looked at work: “29.0% and 47.4% of those who were employed premorbidly were not able to return to work”; “5% to 90% were unable to reach their pre-COVID employment level” (p. 128) (As noted earlier, a lot of the studies in the meta-analysis seem to be small n, involving hospitalized people, without controls, and I don’t know what they did about this. Also, it’s possible I’m misunderstanding what group the meta-analysis is about, given how crazy high the numbers are).

Some harder to interpret data about long covid sufferers in particular (where I’m not sure how many people count as that) still suggests pretty major issues:

Matt bell says that this UK data-set has ~18% of non-hospitalized long covid sufferers with “activities limited a lot.”

And looking at a survey I mentioned earlier again, people with long covid (and probably under selection to be relatively bad cases) report large losses of ability to work, and in other specific capabilities:

  • “The greatest area of impact reported was on work, with 86.2% (95% confidence interval 84.4 to 88.0%) of working respondents feeling mildly to severely unable to work − 29.1% (26.7% to 31.6%) severely…. Other areas of impact included making serious decisions 85.3% (80.7% to 89.8%), communicating thoughts and needs 74.8% (72.5% to 77.1%), having conversations with others 68.3% (65.8% to 70.8%), maintaining medication schedules 62.5% (59.8% to 65.1%), following simple instructions 54.4% (51.6% to 57.2%), and driving 53.2% (50.5% to 56.0%).” (p. 16)

  • “Of unrecovered respondents who worked before becoming ill, only 27.3% (95% confidence interval 25.3% to 29.4%) were working as many hours as they were prior to becoming ill at the time of survey, compared to 49.3% (40.8% to 57.9%) of recovered respondents (see Figure 11d). Nearly half 45.6% (43.2% to 48.0%) of unrecovered respondents were working reduced hours at the time of the survey, and 23.3% (21.3% to 25.4%) were not working at the time of the survey as a direct result of their illness. This included being on sick leave, disability leave, being fired, quitting, and being unable to find a job that would accommodate them. The remaining respondents retired, were volunteers, or did not provide enough information to determine their working status. Overall, 45.2% (42.9% to 47.2%) of respondents reported requiring a reduced work schedule compared to pre-illness. 22.3% (20.5% to 24.3%) were not working at the time of survey due to their health conditions.” p. 27.

E. Other people’s previous back of the envelope calculations on this are not reassuring.

Matt bell:

“If you’re a 35 year old woman, and your risk of ending up with lifelong long COVID from catching COVID is 2.8%, then catching COVID would be the same, statistically speaking, as losing (50 years * 0.18 * 0.028 * 365 days/​year) = ~90 days of your life.”

Scott Alexander:

“Your chance of really bad debilitating lifelong Long COVID, conditional on getting COVID, is probably somewhere between a few tenths of a percent, and a few percent.”

F. Having ‘survived’ covid looks associated with a 60% increased risk of death (after surviving covid) during the following six months

According to a massive controlled study published in Nature (more readable summary here). It also looks like they are saying that this is for non-hospitalized covid patients, though the paper is confusing to me.

I’m not sure whether to model this as some longer-than-a-few-weeks period of danger that is still done within the year (maybe 400 micromorts if done by six months), versus semi-permanently worse health (which would maybe be like aging about 8 years).

This is bad because death, but I’m maybe more alarmed by it because it supports the ‘post-covid illness is some fairly extreme body fuckage of which the fact that some people can’t think straight is merely a tip-of-the-iceberg symptom’ hypothesis over the ‘most of the story is that you lose some work time this year’ hypothesis. Both because death really suggests something wrong, and because they catalogue a lot of things wrong—from the WebMD summary: “The patients had a high rate of stroke and other nervous system ailments; mental health problems such as depression; the onset of diabetes; heart disease and other coronary problems; diarrhea and digestive disorders; kidney disease; blood clots; joint pain; hair loss; and general fatigue.”

It’s also a bad sign about what a bad time you might have during that year. I don’t think these people go gently—it seems like a repeating theme of these long covid stories is that their victims have a lot of health scares and medical investigation, and this mortality data suggests to me that they are genuinely at risk of their lives, which I think would make the experience much worse, for me at least.

G. Overall deaths from everything have been very unusually high at points in 2021, even in 15-64 age group

From Our World In Data:



For context:

(The Center Square) – The head of Indianapolis-based insurance company OneAmerica said the death rate is up a stunning 40% from pre-pandemic levels among working-age people.

“We are seeing, right now, the highest death rates we have seen in the history of this business – not just at OneAmerica,” the company’s CEO Scott Davison said during an online news conference this week. “The data is consistent across every player in that business.”

OneAmerica is a $100 billion insurance company that has had its headquarters in Indianapolis since 1877. The company has approximately 2,400 employees and sells life insurance, including group life insurance to employers nationwide.

Davison said the increase in deaths represents “huge, huge numbers,” and that’s it’s not elderly people who are dying, but “primarily working-age people 18 to 64” who are the employees of companies that have group life insurance plans through OneAmerica.

“And what we saw just in third quarter, we’re seeing it continue into fourth quarter, is that death rates are up 40% over what they were pre-pandemic,” he said.

“Just to give you an idea of how bad that is, a three-sigma or a one-in-200-year catastrophe would be 10% increase over pre-pandemic,” he said. “So 40% is just unheard of.”

H. Sounds like these things involve various damage throughout body, and my guess is that that ends up being regrettable in ways not captured in ‘hours lost to fatigue this year’

See Nature study in F. I also feel like I’ve seen this a lot, but don’t have that many examples immediately on hand. Here’s one other example, not ideal because note that these are hospitalized younger people:

For people younger than 65 who were hospitalized with COVID-19, the risk of death in the 12 months after the infection was 233% higher than it was for people who did not have the disease, results published in the journal Frontiers in Medicine have shown.

Nearly 80% of all deaths of people in the study who had recovered from COVID-19 in the past 12 months were not due to cardiovascular or respiratory causes, suggesting that the impact of the virus is significant and wide-ranging, even after the initial infection has been fought off.

My guess is that all the symptoms are a spectrum, and if the worst looks like an unbelievable amount of cognitive impairment and a pot pourri of organ dysfunctions, or death post-infection, then probably everyone gets a handful of cognitive impairment and organ dysfunction.

I. It’s easy to just think about these worst case outcomes, but there are a lot of more probable non-worst case outcomes that would still be a non-negligible bummer.

I see people mostly estimating the worst cases, but my guess is that the more probable non-worst case outcomes (e.g. lesser fatigues and brain fogs, kidney damage, arrhythmias etc), are not nothing.

J. Future unknowns

Across all diseases, how much of their disutility is obvious in the first two years? Saliently right now: we’ve had Epstein-Barr for ages and only now noticed that it apparently has a ~1/​300 chance of causing MS, usually showing up between 20 and 40, long after the virus, and wreaking brutal destruction. I’m not sure whether we would realize how bad HIV was if it had appeared two years ago and lots of people had it, but nobody had had it for more than two years yet.

K. Long covid probably isn’t psychosomatic

A French study found that long covid is barely associated with having had covid according to an antibody test, yet associated with believing one has had covid (which itself is unrelated to the antibody test results).

At first I (and I think others) thought that if this wasn’t some error, then long covid was likely psychosomatic and not caused by physically having covid. But on further thought, that’s totally wrong: this pattern could be caused by beliefs causing illness, but it could also be caused by illness causing beliefs, which obviously happens all the time. That is, people’s guesses about whether they had covid are heavily influenced by their symptoms.

Imagine a population of a thousand people. A hundred of them get covid this year, and ten get long covid caused by the virus. Fifty and five of those respectively notice that they have covid at the time. Also a hundred people get other illnesses that look like long covid (other viral infections, other mental health problems, other random things). Everyone knows that a lot of people are getting covid and don’t know they have covid. The hundred people who got some other illness that looks like long covid infer that they are plausibly in the asymptomatic covid group, since they seem to have long covid. Especially the ones who got some viral illness, so were actually a bit sick at around the time they developed their chronic illness. So we end up with people who think they have long covid having less covid than the general population, even though long covid caused by the covid virus is genuinely afflicting 10% of the covid infected. Note that everyone here might have non-psychosomatic illnesses.

It seems to me that we have other data that basically rules out the possibility that long covid is imaginary (e.g. see Nature study above on laboratory abnormalities and raised death rate). Though psychosomatic illness is weird—my understanding is that it could in principle still be psychosomatic, while yielding measurable physical laboratory abnormalities, though intuitively I’d be fairly surprised to learn that the same new psychosomatic syndrome had gripped millions in the wake of a particular belief they had, and raised their risk of death by half. Maybe I’m missing something here.

L. The general discussion of what is going on with people’s brains sounds terrible

The list of different plausible routes to brain damage occurring according to Nature—some brain cells getting broken, some blood restrictions causing little strokes, some immune system attacking your own brain type issues—is one I want very little to do with. For instance:

“…The researchers observed that, in slices of hamster brain, SARS-CoV-2 blocks the functioning of receptors on pericytes, causing capillaries in the tissue to constrict. “It turns out this is a big effect,” says Attwell.

It’s a “really cool” study, says Spudich. “It could be something that is determining some of the permanent injury we see — some of these small-vessel strokes.”“

Another sample of current discussion of the brain damage situation that I really don’t want to be a part of, this time from NPR:

Frontera led a study that found that more than 13% of hospitalized COVID-19 patients had developed a new neurological disorder soon after being infected. A follow-up study found that six months later, about half of the patients in that group who survived were still experiencing cognitive problems.

The current catalog of COVID-related threats to the brain includes bleeding, blood clots, inflammation, oxygen deprivation and disruption of the protective blood-brain barrier. And there’s new evidence in monkeys that the virus may also directly infect and kill certain brain cells…

“Frontera was part of a team that studied levels of toxic substances associated with Alzheimer’s and other brain diseases in older COVID-19 patients who were hospitalized.

“The levels were really high, higher than what we see in patients that have Alzheimer’s disease,” Frontera says, “indicating a very severe level of brain injury that’s happening at that time.”…

Even COVID-19 patients who experience severe neurological problems tend to improve over time, Frontera says, citing unpublished research that measured mental function six and 12 months after a hospital stay.

“Patients did have improvement in their cognitive scores, which is really encouraging,” she says.

But half of the patients in one study still weren’t back to normal after a year….”

M. It sounds like covid maybe persists in your body for ages?

Seems like the virus lives throughout your organs long after recovery, based on autopsies, including of mild/​asymptomatic covid sufferers (summary, paper):

“The study found that the virus had replicated across multiple organ systems even among patients with asymptomatic to mild COVID-19.

The virus was detected in all 44 cases and across 79 of 85 anatomical locations and body fluids sampled”

“We performed 72 complete autopsies on 44 patients with COVID-19 to map and quantify SARS-CoV-2 73 distribution, replication, and cell-type specificity across the human body, including brain, 74 from acute infection through over seven months following symptom onset. We show that 75 SARS-CoV-2 is widely distributed, even among patients who died with asymptomatic to 76 mild COVID-19, and that virus replication is present in multiple pulmonary and 77 extrapulmonary tissues early in infection. Further, we detected persistent SARS-CoV-2 78 RNA in multiple anatomic sites, including regions throughout the brain, for up to 230 days 79 following symptom onset.”

This seems like a bad sign for future problems.

Ok, that was ‘covid is bad, primarily due to long covid’. But aren’t we all going to get it anyway?

N. Later rounds of covid are probably bad too

This assumes that later covids are basically free, once you’ve done it once, in a way that isn’t true for e.g. crashing your car. My guess is that later bouts are less bad on average, but far from free.

In my survey, of three people with lasting problems who got covid at least twice, one got the problems with the first, one the second, and one said both contributed (though for the last person, the second was around a month ago). Not a great sample size, but seems like strong evidence that second-round long-covid isn’t unheard of.

O. It’s not 100% that you will get it.

I’d guess there’s a decent chance you’ll be able avoid it, via reasonable-to-pay costs. For instance, maybe omicron basically brings herd immunity. Maybe rapid tests get more reliable, easy, and cheap. Maybe long covid becomes a bigger concern, and people worry enough to get R0 generally below 1. Or other technologies improve: Fend really does cut covid exhalations massively and is taken up widely, or something like Novid finds a way to be taken up. (Or your path takes you to being a hermit or living in China, or we spend next year hiding in bunkers from cyborg bees, and you are glad you didn’t pay all that covid risk up front for parties that aren’t happening.)

(If we were doing exactly what we are doing so far, but with air purifiers in most buildings, would R0 would have been ¼ instead of ~1, and would it have died out? Is the problem that we are psychologically incapable of maintaining slightly more caution than needed to keep infections steady?)

Are things so predictable?

P. The likelihood of you getting it probably does depend on how bad it is

Whether you will definitely get covid depends on your—and everyone’s—assessment of how bad it would be to get. If the high end of possible long covid risks became clearly correct, probably many people wouldn’t take those costs vs. avoiding people who choose to be risky, so the options for low risk lifestyle would improve. Like, at first when people realized that it was potentially quite valuable to wash your hands after various bodily things, it would have been pretty annoying to be one of the few people trying to avoid contact with others so called ‘germs’. One might have resigned oneself to getting every disease contained in anyone’s bodily fluids. But eventually the idea of hand-washing being important has had enough traction that everyone can care a lot about other people washing their hands after using the bathroom say, and it imposes very little burden, because basically everyone has habits and infrastructure that make it easy to uphold hygiene.

If everyone believed that covid was bad enough to get, it would die out in a month (possibly with terrible economic downsides for a month). It probably isn’t that bad, but if it really is quite bad to get, and ways to avoid it exist, people will probably realize that eventually, and adjust.

Q. Getting covid later is probably better than earlier.

So far this trend seems strong: I would rather get covid now than in March 2020. I expect more of this, from better knowledge, medicine, vaccines, and availability of everything we already have.

If I expect to get covid every year for the next five years, adding one more bout now is adding one more especially bad bout in expectation.

R. Huge VOI in following behind the crowd, at a safe distance

I know many people resigning themselves to getting covid this month, and results so far suggest that a lot of them will indeed be infected.

If half of my friends are getting covid right now, there seems to be massive value in waiting another three months before reassessing precautions, so I can see how it goes for them. While noisy, I expect to get a better sense of the distribution of outcomes among people in my reference class—and especially whether there is a macroscopic chance of really dire outcomes—from this (I think regrettable) experiment than I get from cobbling together different studies about vaguely defined symptoms among ambiguous or not-quite-relevant demographics, with various guesstimated adjustments.

There also seems to be a huge amount of uncertainty about how bad long covid is. I and my friends have various intuitions and guesses about where assorted factors of two push in this direction or that, and I doubt any of us should be super confident that we are the one with the right intuitions and guesses.

I think waiting out this spike looks like the right move from a VOI perspective even if your own judgments come out in favor of long covid being probably fine. As long as you are decently uncertain—which it seems to me that you probably should be—there is a lot of information coming in (at least if you are someone in my social circles, but probably a lot of social circles are coming to have a lot more people with covid this month).