taw's blog: Pandemic Retrospective

There won't be anything too controversial here, just a bit of big picture view.

Basics

Covid-19 is not over, and there's no indication that it will ever be eradicated, there are just a lot more important things going on right now.

So far the only established human disease we managed to eradicate was smallpox. Polio eradication efforts have largely stalled, with little progress since year 2000. I still have some hopes that we'll win over polio, but the chance of total elimination of covid-19 in any realistic timeframe is essentially zero.

The most outcome is that covid will be just another seasonal disease like the flu, with us for the long run. This is mostly fine, as going forward, most people will get exposed to mild infection when they're young, and by the time they're old and vulnerable, they'll have some degree of immunity, from some combination of previous infections and vaccines.

Age is the main risk factor, far greater than anything else. Every extra 20 years means 10x higher death rate, or in other words every additional year of your life is extra 12% risk of death if infected.

This is a good way to put things in perspective. For example according to the few RCTs we have, masking (with a real medical mask) may offer about 10%-20% reduction in infection chance, with no reduction in severity of symptoms in case of infection. So you're about as vulnerable masked in 2022 as you'd be unmasked in 2021, just because you aged enough to counter all that benefit. And "masking" with non-medical mask doesn't seem to do anything at all.

Vaccination with regular boosters may reduce risk of death by about 80%-ish, equivalent to being about 15 years younger. So a fully vaccinated and boosted 40 year old is at about as much a risk as completely unvaccinated 25 year old. There doesn't seem to be much reduction in chance of getting infection in the first place, mostly reduced severity.

It's often underestimated just how much covid is a single-risk-factor disease, that factor being age. For example obesity increases risk of covid death by 25%. So 40 year old obese person is at as much risk as 42 year old healthy weight person.

I think it's a useful visualization tools to translate all relative risk factors into equivalent age differences.

Risk of hospitalization and other serious health outcomes roughly follows risk of death, with similar risk increase for every additional year of age.

Anti-Covid Measures

There are three stages at which we could intervene to prevent covid deaths (and other severe outcomes):

prevent pandemic from getting to your country in the first place
reduce spread of infection once there's already community spread
reduce chance of death for an infected person

A lot of measures have been taken, but only two have been very highly effective:

total border closures (step 1)
vaccinating old people (step 3)

Everything else did either nothing, or had minor effect, or was outright counterproductive. These include such measures as:

bank account closures
contract tracing
firing people for having different opinion
hand washing
ivermectin
lockdowns
mask mandates
masking
mass event closure
partial border closures
quarantines for travelers
riots
school closures
social media bans
stimulus checks
testing
vaccinating low risk people
vaccine mandates
voluntary masking
work from home
etc.

In the end, none of them had a big impact on the death rate. Notably almost all the measures attempted to target stage 2 (reduce infection rate once it's already established), and for covid that was simply the least effective stage to target.

The most unexpected thing about covid is that stage 1 interventions (total border closures) were extremely effective even after covid already got established. The original Wuhan lab leak variant was just not all that infectious, so closing borders and preventing much more infectious subsequent variants from coming in was an extremely successful approach, even in absence of other interventions. Japan is a good example of this combination.

Cargo Culting

A huge problem with global pandemic response is that countries threw away all established science, and mindlessly copied what other countries were doing, even if it was completely ineffective. So instead of 200 different policies we could meaningfully compare, it's largely same ineffective policies tried over and over.

Knowing just country age structure, border closures, and vaccination rates among old people, we can fairly accurately estimate pandemic severity, throwing away all other information.

Arguably the main problem with global pandemic response was that everyone was cargo culting part of Chinese response that was pointless (lockdowns), and in a half-assed way that couldn't have possibly worked anyway; and they did not copy the part of Chinese response that actually worked (total border closures).

What Was Not Tried

In retrospect was can safely say that nothing targetting stage 2 would have worked. Any response strict enough to eradicate transmission after it was well established would just completely crash the economy, and with borders even partially open, covid would get back in anyway. And if you closed the borders, then you didn't need to be that strict in the first place (see Japan again).

At least none of such interventions would work if they targetted general population. We could have absolutely done crazy strict lockdowns of nursing homes specifically. About a third of all covid deaths in US was in long-term-care facilities, and these are not economically significant. We could have completely isolated them from the rest of the population (food delivery in full body ppe suit kind of isolation), and likely avoided 1/3 of all covid deaths. By moving more old and vulnerable people into similar protected environments, deaths could have been reduced even more.

Nobody really tried that, and there's been overwhelming lack of interest in any interventions that segregated people by risk level. If we did something more along the lines of:

no restrictions of any kind on under-30s
some modest risk reduction recommendations for 30-60s (no mass events, work from home recommendations, masking on public transport recommendation etc.)
total lockdown for 60+s

That would be far more effective and far less destructive than what actually happened. To repeat the basic fact, 20 years of age difference means 10x risk of death difference. There's no sane way to treat kids and elderly the same, and that's what all countries did.

More idiotically, students were often restricted far more than adults, just because schools have far too much power over students' personal lives. It was cruel, and it did nothing to help with the pandemic.

There's some stage 3 interventions that could have had a meaningful effect, but weren't attempted.

The most notable one that would be mass vitamin D supplementation, as pre-infection vitamin D levels correlate very strongly with risk of death, and vitamin D insufficiency has been widespread in most modern populations. For people with most severe deficiency, effect size looks about as big as vaccines, based on observational studies. It would be much smaller averaged over entire population, as not everyone is as severely deficient. Unless you know that your vitamin D levels are adequate, you should absolutely get daily supplement, especially during winter, and not just for covid.

There's also some new antiviral drugs that could reduce risk of death. They happened late in the pandemic, but I guess if someone writes similar retrospective in 2025 they might get added to the list of interventions that made a big difference.

There's also an interesting idea for stage 1, to totally close not just countries but each city and region, and wait for covid to disappear there, before reopening only borders between covid-free areas. But this would only work if external country borders were closed as well, and it would be extremely disruptive. China sort of did that initially, but nobody else really tried that at all.

Who Predicted It Correctly?

Nobody at all.

Pre-pandemic expert consensus was very strongly against lockdowns, border closures, masking, and most other measures that ended up happening. Pretty much none of that was followed.

Epidemiologists' models were all universally worthless, and the whole field of epidemiology turned out to be about as reliable as social psychology.

Governments were both extremely incompetent and openly lying. The media were even dumber than usual. Social media companies were banning people for saying true things.

I don't think even any individuals got it right. As far as I know, nobody predicted either of these:

the initial Wuhan Lab variant was no big deal, the variants were a big deal, so total border closures would be super effective even after Wuhan lab leak variant was already there
vaccines would be developed very quickly, but they'd only offer big redution in severity and risk of death, and wouldn't meaningfully reduce infection rate, so mass vaccinating old people was really important, but any mass mandates are pointless

I don't think anything useful came out of prediction markets either.

Who Did Well?

The private sector did amazingly well. Rapid transformation of big parts of the economy from office-based to remote-first was amazing, and we should absolutely embrace the remote-first world, even if it made little difference for covid.

Similarly supermarkets, restaurants and so on switched very effectively from location-based services to delivery-based services. Restaurants have a lot more reason to exist than offices, but this shift is likely permanent, and a much bigger share of the economy will be online or delivery-based going forward.

Big Pharma did quite well. Multiple vaccines were developed in record time, of kind not used ever before, for kind of a virus that never had an effective vaccine before. Tests, antivirals, and so on were also developed very quickly.