The infection fatality rate for covid, averaged across the population, is somewhere around 0.2%. If you infect a million random people, ~2000 will die from it. Obviously this varies wildly by age and other risk factors (see discussion below), but this is a good place to start. "If you get covid, you're about X times more likely to die than if you got the flu." This anchors the risk to something we're familiar with. Whatever precautions we typically take to avoid getting the flu, we should scale them up accordingly. That's not to say proportionally. If your risks are 10x that of dying from flu, you may be willing to spend more than 10x the cost in avoiding it. People tend to be risk averse. Still, it's a good starting point to adjust from, not some utterly alien concept demanding an arbitrarily large up-scaling of precaution measures. It makes sense to ground those decisions in something we're familiar with, and the flu is a good place to start.
The other piece to consider is your risk of getting infected. Obviously covid is much more transmissible than the flu. Looking at some data at this CDC page, it looks like there are ~30 million flu cases in a typical year. Let's suppose covid is so transmissible that nearly all Americans are going to get it under a "business as usual" regime, call it 300 million covid infections (about 90% of the US population). That's another useful piece of information. "Covid is like the flu, but you're 10x as likely to get it." (Or whatever the multiplier is, I'm not wedded to any particular point estimate.)
There's a philosophical question about whether I should care about the second piece of information, the likelihood of transmission. I generally don't scale up or down my caution with differing flu seasons. It's just something I'm inured to. Though possibly this is just because flu is below a threshold for risk that I can just rationally ignore. Maybe I would respond if there were a flu season where the active strain that year is 3x or 5x as transmissible? Or maybe I'm appropriately applying a heuristic that "Getting sick is part of life, mitigation measures aren't that effective. I'm inured to these kinds of risks, and I won't change that unless something truly deadly comes along." The notion of scaling up and down my precaution for very active versus less active flu seasons seems weird to me. But maybe it's actually rational to do this and I'm bad at updating my behavior. I'd probably be more likely to get a flu shot if experts were projecting a truly bad flu season. (If I didn't, my wife, who is in health care, would gently nudge me to get the shot.) But I don't see myself socially distancing or masking up for a "bad flu season."
The most relevant piece of information is the extreme age stratification. "It's kind of like the flu in terms of overall symptoms and infection fatality rate, but it basically doesn't cause problems in children below age 12, it's similar to the flu for ages (say) 20-40, and above age 65 it poses a serious risk of death." Add in some caveats about specific risk factors like obesity, diabetes, pre-existing lung disease, etc. This is something that really would affect my behavior. "I'm basically fine, I shouldn't undergo any particular precautions for my own benefit. But I should avoid elderly or infirm members of my family, or at least take some precautions, until the pandemic subsides." Many years ago, my wife and I were picking up an elderly member of the family for a family gathering. She lived in an old folks home, and there was a sign at the door warning that anyone with flu symptoms should stay away. I kept that thought with me. It made me aware that a mild illness for me could be a fatal infection for someone who's not so healthy. It was probably worth scaling up this sense of precaution by a factor of ten or more as a response to Covid, whatever that entails. But it made little sense for young people who are mostly encountering other young people to scale up their precautions. As I pointed out in a prior post, young people vastly overestimated their risk from covid, presumably causing them to take irrational precautions to avoid the virus.
We are, as a collective, utterly incapable of rational risk calculation. Dominant media narratives and messaging from "public health" institutions fail to put the panic porn into perspective. We become totally inured to significant risks, like automobile accidents, but obsess over insignificant risks, like an opioid prescription turning us or our neighbors into mindless drug addicts. We obsess over determinants of health that don't matter, like economic barriers to health care, but fail to take simple, inexpensive steps that would improve our health and longevity, like exercise and improved diet. Our experience with covid over the past two years has really driven this home for me.
Note that there are two determinants in the "how much should I worry/take precautions" calculus. One is the magnitude of overall risk (assuming the problem is unmitigated). If covid had the mortality rate of small pox, I'd be singing a very different tune. The other determinant is "How effective are mitigation measures?" (There are some things you can't do anything about.) I think people are badly overestimating on both fronts, so it's leading to costly interventions that don't stop the spread. Studies on the benefits of masking are at best inconsistent. (Read the first few studies on this question that Google returns. That's studies, not opinion pieces or news columns. I see a lot of very wide confidence intervals on the odds ratios that surround 1.0, implying the statistical tests can't tell if masking is helpful or harmful.*) The supreme confidence in their efficacy is not warranted, neither is the outrage directed at people who refuse to mask up. Likewise, the closing of schools was never warranted, nor was the closing of outdoor spaces. It was well known early on that children were unlikely to be harmed by the virus and also quite unlikely to transmit it. It was also known that the virus did not transmit effectively outdoors. No matter how dangerous the virus is, it makes little sense to conduct ineffective hygiene theatre out of a misguided sense of "do-something-ism".
The almost daily references to the total body count are totally irrelevant. (I also wouldn't mind if people stopped converting the body-count to "9/11s". As in, "This is like having three 9/11s each week!") What matters is the plausible counterfactual, where cost-justified interventions were taken. Maybe some commentators are thinking that most of the deaths were avoidable (something I think isn't remotely plausible), so it's okay to cite the raw total as an order of magnitude estimate? I wish they'd be clearer about their assumptions. An earlier rollout of the vaccine may have cut the deaths by some large percent, though it's clear now that new variants are evolving to evade the narrowly-tailored mRNA vaccines. It's possible that an earlier vaccine rollout would have simply driven the evolution of new variants to an earlier point on the timeline. Then again, the vaccines appear to protect against extreme illness and death, even if they're losing their effectiveness against preventing infection full stop. "It's a lot like the flu, except it keeps evolving to evade available vaccines. Also, that's not really different from the flu. It's something we're familiar with."
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* On the masking question, people will sometimes acknowledge (or brush aside as "underpowered") the studies that show weak or null effects of masking. They'll then retreat to an a priori explanation of why they should work. "A mask filters x% of incoming air, so it's at least x% effective" or the contrary "The virus is too small to be blocked by the matrix of cloth in a mask, and there's adequate airflow around the mask anyway." Or even, "A mask blocks outgoing droplets, but then you're breathing and blowing on it for the next hour or so. This generates more aerosolized virus than if you just went maskless." Whether masks are slightly helpful, benign, or hurtful is an open question. Again, see the lower confidence intervals on some of the studies that Google returns.
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