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Comment by jerf | Hacker News Reader

Coronavirus will naturally evolve into the attraction basin for viruses of its type, which is the common cold: https://www.sacbee.com/news/coronavirus/article248455480.htm...

It's already well on its way, from what I can gather.

One frustrating aspect of the reporting for me is people talking about "more infectious" variants without describing whether or not they are more or less dangerous. In general, the virus putting more work into being infectious is good news; it generally comes at the cost of being less dangerous in other ways as it hyper-optimizes into replication rather than anything else. We should expect and want to hear about "more infectious" variants, which double as natural vaccines to some extent against other less infectious, more dangerous strains still using the same external protiens.

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There's a substantial lag, though, between finding out how infectious a variant is and how deadly it is (AIUI the rough averages are 2 weeks from infection to hospitalization and another 2 weeks from hospitalization to deaths, but that might have changed). That means that the data on how infectious a variant is becomes available ~1month ahead of information about how dangerous it is. Have we even had confirmed spread of these variants for a month?

BBC’s _More or Less_ did a bit on this. 70% more deadly (per person) would actually be better than 70% more infectious. Deaths increase linearly with deadliness of virus, but they increase exponentially with infectiousness.

Say the current mortality rate is 2% and each infected person passes on the disease to one other after a week, then stops being infectious. If 100 people have the virus in week 0, after 10 weeks 1000 people will have had the virus and 20 will have died.

Increase the death rate by 70% and you’d have 34 deaths instead. Increase the transmission rate by 70%, and you’d have 170 people newly infected in week 1, then 289 in week 2, totalling 285,000 infected people, of which 2% die. That’s now 570 deaths.

Obviously the numbers can all be changed somewhat depending on treatment, or whether you expect everyone to be infected at some point anyway, but the takeaway is that more deadly is not necessarily worse than more infectious.

Factor of 10 failure: 28,500 infections, 57 deaths

There is some talk that it also _is_ deadly. https://www.theguardian.com/world/2021/jan/22/new-uk-covid-v...

It may be, but that article is also hedging quite a bit.

People have a hard time with this intuitively, because we probably live under the weakest selection pressure in the history of planet Earth, but it's vicious down there. Viruses are to a large extent playing a zero-sum game. If they get better at one thing, it almost has to come at the cost of something else, because they've already got all the knobs cranked up as high as they will go just to survive and they don't have a spare energy budget just lying around to put into other things without taking away from something else.

It's not impossible that some mutation was made that made it more infectious and more deadly... but it's a long enough shot that I'd consider the likelihood of incomplete early information and incentives that some parties have to amp up the danger in the presence of such uncertainty higher. Viruses do not routinely become more infectious and more deadly. If they did, we'd all be long dead. The evolution gradient tilts strongly away from that.

Very true, especially when you consider that a more deadly variant is highly likely to be associated with things like higher viral load, worse symptoms, and faster symptom onset. A virus that kills twice as many people will likely be harmful for twice as many people -- giving the virus fewer asymptomatic hosts that go around spreading without even knowing it.

It's more likely to go the other way; some derpy mutation that reduces viral load, slows incubation, reduces symptoms, makes more super-spreaders.

The virus exists in multiple species. It may be perfectly fine in bats and reproduce without killing the bat. In humans, however, it kills.

"30% more deadly" means that only 99.6% of people survive it rather than 99.7%. Still not ebolapocalypse.

People need to stop reading these articles and start exercising. If this virus hit 40 years ago when hardly no one was obese this virus wouldn't even be a thing.

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