Asymptomatic

September 25, 2020

There’s that old parable where, suddenly, people can’t bend their arms. There’s plenty of food to eat, but people are starving… because they can’t reach their mouths.

The parable goes on to explain how, actually, it’s only the self-serving narcissists that are starving. The good people have figured out that all they need to do is feed each other, and everyone will be ok.

To some extent, we’ve been told that masks are sort of like that; you wear one, more than anything, to help others; to avoid you infecting them with your sneezes and coughs… and, as long as everyone is doing that to help others, we all benefit.

For a lot of my life, I thought catching a cold or flu was like getting pregnant; you’re either pregnant or you’re not. Similarly, either you have a cold… or you don’t. Certainly, you can be 7 weeks pregnant vs. 7 months, and it’s a very different experience… just like you can have a mild cold or a really bad cold.

The subtle difference in my mind was this: Once you have a cold, how bad it is depends on that particular cold virus. Some hit you really hard, while some give you little sniffles. Some years it’s really bad, some years… not so much.

What I didn’t understand was the whole concept of viral load. It’s not necessarily the severity of the strain of the virus… it’s also how much of it you got. The actual level of dosage, the actual number of little virus balls you inhaled… like, how badly you were infected… has a huge influence on how it affects you.

This is becoming very evident with the analysis of C19 patients; those exposed with high viral loads have a much more difficult journey. In fact, viral load at the time of diagnosis seems to be, on its own, an independent predictor of mortality.

All of this goes back to masks, and a recent article that pointed out something that should be pretty obvious, but perhaps hasn’t been made abundantly clear: If you wear a mask, you’re not only protecting others, but you’re protecting yourself. Your chances of receiving a lethal infectious dose are dramatically reduced if you’re wearing a mask.

Further to that – a very promising conclusion that follows from that is that by wearing a mask, you may well be creating immunity in yourself. As we know, a vaccine simply stimulates an immunity response… well, guess what… you may already have done that, in small doses. We also know that 80% of cases are asymptomatic, and that may in large part be due to the low viral loads that caused them in the first place. Perhaps the small amount you got from a distant sneeze. Or, perhaps, the small amount you got from someone nearby… but your mask took the hit, and all you got was 1% of the potential viral blast in your face.

And one final (also promising) conjecture… it seems that even tiny viral loads in your body may stimulate strong immune responses. By the time the vaccines roll out, you may already be immune… and only because you’ve been wearing a mask, self-vaccinating yourself in small doses.

I’m not sure any of this will change the minds of the ardent anti-maskers, for whom this whole issue is entangled with political (and other) agendas… but if you know any somewhat-reasonable anti-maskers who think it’s not worth it for medical reasons, feel free to pass this along. Or maybe to that “me me me” narcissist who doesn’t feel the need to benefit others, at the expense of their personal comfort. Well, guess what… it may benefit you greatly.

And for the rest of you reasonable people, just keep doing what you’re doing… and wear your mask with the knowledge that your little contribution to the greater good may actually be doing a lot more good than you think.

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July 21, 2020

It was Arthur C. Clarke, notable author, inventor and futurist, who’s quoted as saying, “Any sufficiently advanced technology is indistinguishable from magic.”

Very true indeed. We all take for granted technology these days that would baffle even the brightest minds of not-so-long ago. The little phone you carry around (and perhaps with which you’re reading this) is a prime example. We get mad at it when “the stupid thing isn’t working”, but you’d think about it differently if you considered the complexity of the underlying infrastructure that makes it all work. Imagine someone 50 years ago watching you take a picture with your iPhone. OK, fancy tiny camera… very cool. But not impossible. And then they watch you AirDrop™ that picture to the person next to you. That’d be nothing less than magic.

I’ve been around long enough to see true innovative technology arrive, explode onto the scene, and then slowly drift from relevance as newer, more advanced technology took over. For example, CDs. They appeared literally overnight (from a consumer point of view) and took over the world. They were, for a time… magic. And they have since drifted into obscurity.

One interesting thing in the early days of CDs was both the marketing and technology of what was called “oversampling”. There’s more to it than what I’m going to describe, but basically it was this – the laser that’s reading what’s on the surface of the disc has about a zillionth of a second to bounce itself off a particular spot and decide whether it’s a one or a zero. And it’s not always right. Since that’s happening 44,100 times per second, it’s not a huge deal if it gets it wrong once in a while. But, that depends how wrong… your music quality would tend to degrade, and if it’s data, it has to be perfect. Data inherently is stored with what are called “CheckSums” – that verify the integrity of the data. For example, a simple version might be that after every 1,000 bits, it tells you how many zeros there were. And also how many ones. If those two numbers don’t add up to 1,000… there was a problem, so read it again. Credit card numbers also have a built-in sanity check… VISA numbers start with 4, MasterCard with 5… but not just any random string of 15 digits after that will work. In fact, only one in ten.

But music isn’t stored that way… it’s just sample after sample. So what they did is this… they’d get the laser to sample each bit more than once. 2x oversample. 4x oversample. 8x oversample!! If 6 of 8 of those reads say it’s a one, go with that.

If this sounds just like adding more and more blades to your razor, you’re right. At some point, the diminishing returns no longer make sense. How many blades do you need to get a perfect shave? I don’t know, but I know that two blades are better than one. Four is perhaps better than three. But I’m not sure 27 blades on some 6-inch razor are better than 26.

With CDs, I once saw a model boasting 96x oversampling. Come on.

This all comes to mind when reading numerous articles about COVID-19 testing. Rates of false positives. Rates of false negatives. People who’ve tested negative then positive then negative then positive. Good tests, bad tests, expensive tests, cheap tests.

In some cases, it’s a threshold… you could have it, but not in a high enough concentration to test positive. This is exclusively a problem for asymptomatic cases; I have yet to read about a test that reports a false negative for someone with symptoms.

Just thinking out loud… it makes me wonder… what would happen if you treated testing the way those CD players used to it. Do 8 cheap tests on someone all at once… instead of a far more expensive single test whose failure rate is lower, but not zero. Like I said, just thinking out loud… but one path of managing this involves testing; lots of it. And if you form a triangle of “cheap, fast, accurate” and have to pick two at the expense of the third… perhaps “cheap and fast” is the angle to go with. This is just simple statistics… not magic.

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