Covid-19 pandemic

[Balderdasha]

Europe has just exceeded 260,000 deaths.

[Balderdasha]

Asia has just exceeded 240,000 deaths.

[Balderdasha]

Per population Asia is doing much better. The current population of Asia is around 4.65 billion, whereas the population of Europe is about 748 million. Or Asia's population is more than six times higher than Europe's, but its death toll is 20,000 fewer.

[Balderdasha]

Meanwhile, South America has an even smaller population, around 432 million, and an even higher death toll of 290,000+.

[Balderdasha]

The North American population is only about 369 million, and it is edging close to a death toll of 350,000.

[Balderdasha]

Africa has still reported fewer deaths than the UK, currently 42,379.

[Jimski]

So, here's a question that's been going through my mind. Perhaps Janik or Jimski or someone else can help answer it:

If a vaccine is only effective for, say, 6 months, does that mean it's actually useless? I wonder because if a vaccine is, say, 80% effective for 6 months, and you can, say, vaccinate 80% of the public within 3 months (assuming that 20% are immune compromised or slip through the net), would the remaining 3 months not have the same impact as a full 3 month lockdown? Shouldn't that be enough to break all the transmission chains in your jurisdiction and get you into a position where you really could use localised test and trace - and also re-vaccinate small populations in areas that are found to have subsequent outbreaks?

A temporary vaccine should be able to be re-applied, right? So you should be able use a short-term vaccine as a successful tool to effectively eliminate the disease even if it doesn't offer lifelong immunity.

I only know what I've read about these issues. I'd imagine any vaccine that has any length of effectiveness would be useful, as it could be used as a tool to reduce R, but yeah, I should really leave it to someone who knows what they're talking about!

[matt j]

My county (in the US) is averaging 200+ cases per day over the last week, or right around 40 per 100k.

Our positive test rate just crossed 10%. Again.

We've had ~300 deaths, or ~60 per 100k.

The school district is returning to full remote learning. It has had 4 confirmed classroom outbreaks, and more than 200 kids quarantined.

Still have people with yard signs complaining about schools/shops/whatever being closed.

We're gonna hit 1/1000 dead, and probably already have nationally.

And this is a 'pretty good' county.

[ursus arctos]

https://twitter.com/COVID19Tracking/status/1321946899918647297

[Janik]

So, here's a question that's been going through my mind. Perhaps Janik or Jimski or someone else can help answer it:

If a vaccine is only effective for, say, 6 months, does that mean it's actually useless? I wonder because if a vaccine is, say, 80% effective for 6 months, and you can, say, vaccinate 80% of the public within 3 months (assuming that 20% are immune compromised or slip through the net), would the remaining 3 months not have the same impact as a full 3 month lockdown? Shouldn't that be enough to break all the transmission chains in your jurisdiction and get you into a position where you really could use localised test and trace - and also re-vaccinate small populations in areas that are found to have subsequent outbreaks?

A temporary vaccine should be able to be re-applied, right? So you should be able use a short-term vaccine as a successful tool to effectively eliminate the disease even if it doesn't offer lifelong immunity.

I've tagged the problem here. That rate of vaccination is almost impossible to conceive of. You would be lucky for a one-off mass immunisation campaign to manage 80% of a population in a year. Most estimates for the mass roll out suggest more like two years to get that many people. And again, as a one-off thing, not a continuous programme of re-inoculation. That is before the vast, expense of such a programme is taken into account.
A vaccine with the sort of effectiveness you describe is maybe of limited use in very local settings to try slow runaway outbreaks, but using it in the way you describe would just overwhelm health systems in another way.

[Hot Pepsi]

Well then we’re all just going to die then?

[ursus arctos]

The more likely outcome is that the virus will eventually mutate to become less lethal

[Janik]

The more likely outcome is that the virus will eventually mutate to become less lethal

That is the normal outcome of pandemics. Indeed it is the likely to have happened with some of the other Coronaviruses we call 'common colds' - they may have been as deadly as this when they first jumped species into humans, but have since evolved into something mundane as all selection pressures on them push them that way.
But for the mutation to propagate when it occurs, SARS-CoV-2 has to be allowed to spread. And this is a serious issue as our track-and-trace efforts are design precisely to prevent that happening. A mutation to being less lethal will still come up as a positive for SARS-CoV-2 on a PCR test, and that outbreak will be attempted to be suppressed by the health authorities that find it as they won't know at that point that the it only kills half as many people (a one jump mutation from very deadly to a snuffle is unlikely, it is going to be cumulative mutations that gradually downgrade this). Indeed these beneficial mutations may already have been happening... and been rapidly wiped out. We can't expect to interfere with evolution in ways like track-and-trace does without it having unintended consequences.

[Hot Pepsi]

Well, we don’t seem to be tracking and tracing much.

[ursus arctos]

It is difficult to understate what a shit show the US is compared to other countries.

[San Bernardhinault]

Although we'd be more likely to test people infected with a more virulent strain than a milder strain, which could provide additional evolutionary pressure on the virus to become more harmless.

[S. aureus]

That is the normal outcome of pandemics. Indeed it is the likely to have happened with some of the other Coronaviruses we call 'common colds' - they may have been as deadly as this when they first jumped species into humans, but have since evolved into something mundane as all selection pressures on them push them that way.
But for the mutation to propagate when it occurs, SARS-CoV-2 has to be allowed to spread. And this is a serious issue as our track-and-trace efforts are design precisely to prevent that happening. A mutation to being less lethal will still come up as a positive for SARS-CoV-2 on a PCR test, and that outbreak will be attempted to be suppressed by the health authorities that find it as they won't know at that point that the it only kills half as many people (a one jump mutation from very deadly to a snuffle is unlikely, it is going to be cumulative mutations that gradually downgrade this). Indeed these beneficial mutations may already have been happening... and been rapidly wiped out. We can't expect to interfere with evolution in ways like track-and-trace does without it having unintended consequences.

Ultimately the less lethal strain will win, as suppression will be imperfect.

[Hot Pepsi]

But I just read a long thing in Nature about how this doesn’t mutate very fast.

[ursus arctos]

Which is yet another reason why listening to Scott Atlas will get hundreds of thousands of people killed.

I am genuinely worried that the GOP will react to defeat by promoting the maximum carnage possible before the inauguration.

[Hot Pepsi]

Yeah. But really, they’ve just given up doing anything, so states and localities can try.

[Jimski]

Although we'd be more likely to test people infected with a more virulent strain than a milder strain, which could provide additional evolutionary pressure on the virus to become more harmless.

This makes sense. If we have effective track and trace in place, it is still unlikely to be 100% perfect. The type of virus that could best evade it would be completely asymptomatic.

[Sam]

The good news for those of you in Afroeurasia is that things down at this end of the Americas are just as non-existent track-and-trace-wise as our US posters report, so if the same is true of all the places in between (and given the economies and politicians we're talking about I have no reason to think that won't be the case) there's a decent chance of a more friendly strain or five evolving over here, at least.

[Moonlight Shadow]

The FT reports that the prevalent strain in Europe now emerged as a mutation in Spanish farms that was spread widely by holiday travellers in that country. 80% in UK are the new strain...

[Patrick Thistle]

Is that a less deadly strain?

[Antepli Ejderha]

The FT reports that the prevalent strain in Europe now emerged as a mutation in Spanish farms that was spread widely by holiday travellers in that country. 80% in UK are the new strain...

So all those people that had to go on holiday because they needed a break have brought this back and spread it.

I wish I was a selfish prick rather than an idiot that stayed at home, followed the WHO guidelines and thought of others.