So, herd immunity. What percentage need to catch Covid 19?

[somanydevices]

I've read 60% or 70% of the population need to get it, does anyone know?

If 1% die, then that's about 400,000 deaths I think, is that about right? Or 5% would be 2 million.

That's what we're aiming for? This is nuts surely?

Did the sums in my head, anyone want to check them please be my guest!

I've read 60% or 70% of the population need to get it, does anyone know?

It is estimated (from observations in Wuhan and the Diamond Princess) that the basic reproduction number R0 (the number of people each infectious person infects on average when nobody has immunity) is 2-3 for COVID-19. That means the herd immunity threshold (the percentage of the population who need to be immune for the virus to stop spreading) is theoretically 50-60%. The formula is (R0-1)/R0.

However, not everyone will survive, not everyone will develop immunity, immunity could wane so those who were infected at the start may lose immunity before the threshold is met, and the people who are immune would need to be spread evenly amongst the population.

The models used by epidemiologists are able to factor in other variables and are much more complex but they are based on that very simple equation.

No-one knows. It's all guess work T this point. We don't even know if it is possible to build herd immunity. We don't know enough about this virus or how it will mutate over the coming weeks/months/years.

OK so if it's 50% for herd immunity (best case scenario) and "only" 1% die, then that's over 330,000 deaths, right?

So Boris Johson has basically decided that these people should die, for a gamble.

Why are people OK with this?

Blinded with science? Deference to power? Can't actually believe what he's saying?

Because it looks a lot to me like Boris ia a meglomaniac murderer and people are just waving him on.

Am I missing something here?

I think we will be able to slightly lessen deaths if we can flatten the curve to make sure the nhs has it's best shot at coping but realistically at this stage we can't stop the spread, we can delay it, try to slow it but not stop it.
That's what most people seem to be struggling to grasp. It's not going away. It's just not possible at this stage to make it disappear completely. It spreads to easily for that to happen.

We're not doing anything to flatten the curve (apart from telling over 70s not to go on cruises).
1% CFR is very conservative - it's 3.5% worldwide and up to 6.4% in Italy. With our health system already at breaking point, and no efforts having been made to slow the outbreak, we will have a huge surge of critically ill patients that will overwhelm our health service and have a much higher mortality rate.

Assuming 60% get it, that's almost 40 million people. Of those,

• 14% are seriously ill, requiring hospital treatment, that's 5.6 million
• 5% critically ill, that's 2 million
• 0.7% die, that's 280,000

The percentages I'm using are from and Irish news programme, who said they're based on Italy and China.

Bear in mind we have about 4000 ICU beds in England (number is from the Independent newspaper and I don't know about Wales, Scotland or NI but they have smaller populations so probably fewer ICU beds than England). And remember that the ICU beds are already needed for a lot of other illness. And that if doctors can't properly treat the critically ill the fatality rate will go up.

There's a reason no other country is even attempting the "herd immunity" plan. It seems like absolute insanity to me. But I'm not an expert in either virology or behavioural science. Those experts have asked the government to release the evidence behind the decision so it can be properly scrutinised - until then we have to trust that the government knows something we don't.

The UK only wants to flatten the curve enough to avoid the existing flu season. If the serious cases occur in the summer then the decision to ICU (or not) can be based on the patient’s ability to cope with it rather than the hospital’s ability to provide ICU. It’s not the best plan but considering the levels of under-investment in the NHS and hospitals in particular there isn’t a better way. I’m sure even in a best case scenario patients may still need to travel to Europe for treatment if we don’t have enough beds.

I also need to point out that as per the current ‘rules’ around ICU there are a lot of healthy people young and old who wouldn’t qualify. I have a female relative in her sixties who is obese and had a stroke so has limited mobility - she already can’t have most Cancer surgeries and I imagine if she needed ICU for any reason we would be told gently that it wouldn’t happen.

Of the 2 million who may need critical care (compared to less than 300,000 in a typical year in England) there's just no way to avoid rationing care and ICU beds. Even if half weren't likely to cope with ICU treatment and therefore don't place any demand on ICU beds that would still leave an enormous gap. Moving away from flu season may free up a number of beds, but even if every single one was available it still wouldn't be enough. When they talk about "flattening the peak" the numbers just don't seem to stack up, unless you're talking about stretching it out over years.

But, again, when the government release their evidence and models we may know more. And I seriously hope I'm wrong.

until then we have to trust that the government knows something we don't

Trust a bunch of privileged etonions who see us as plebs with my life? And the lives of my loved ones? You've got to be joking.

They just told us they're gambling on them.

Just read they plan on isolating over 70s but forcing schools to stay open so the rest of us catch it basically.

Does anyone know if this is true?

From what I’ve heard there’s no guarantee or herd immunity. It’s quite a gamble.

The virus can mutate.

It’s not the best plan but considering the levels of under-investment in the NHS and hospitals in particular there isn’t a better way

Of course there's a better way. We could follow the lead of those Asian countries who've had a low death rate or at least fucking try.

Not gamble with our lives. A plague on their houses. Hope Boris gets it soon.

It’s quite a gamble

And he's gambling with our lives.

Where the fuck are our opposition?

@somanydevices They’ve buggered off by the looks of it

until then we have to trust that the government knows something we don't

The thing is, I dont trust the government. Boris (who is the government now) is an extremely untrustworthy individual and he has done nothing to convince me he has changed since becoming PM.

Yes, 60-70% according to this professor.

www.theguardian.com/world/2020/mar/13/herd-immunity-will-the-uks-coronavirus-strategy-work

The problem is that the government is taking a gamble on whether herd immunity is possible - It is a very new virus and we know little about it and whether you can get it more than once or whether it will mutate into different strains like seasonal flu (we have never had a fully effective vaccine for seasonal flu because it involves a guesstimate of which flu strains will be worst).

But the government plan is to infect 40-60 million people - which even if you assume a death rate of 1-2% would mean deaths of 400,000-1,200,000 in Britain.

This is so difficult, but looking at the infection and death rates in other countries nothing is really working. What the government are aiming for is that the lowest risk groups become infected and become immune, therefore can not infect the higher risk category. Hence the death rate will reduce. Whether it will work will become a major thing in the telling of our history in years to come. I can’t see anything the government does at the moment would be positive in a lot of eyes, as if we shit down the country people may not die immediately of the virus, but may do due to poverty. Damned if you do damned if you don’t. Hope you all stay safe 😞

The idea of herd immunity is being challenged by lots of scientists. So half a million people die to test out a disputed theory?

Shut down not shit down 😱

@Thepigeonsarecoming That simply is not true that nothing is working. Look at countries like Taiwan. If governments follow WHOs advice the virus can be brought under control.
But our government think they know better than everyone else.

And why would people die of poverty from a three month shut down? The Government can mitigate hardship. It can put in things to protect people.

I am totally fed up of the Government;s attitude. It basically seems to be - that is too hard to do. When other countries have managed it. No one is saying this virus is easy to fight. But it takes real leadership, good bold decision making and the strength to see it through. Boris shows none of that.
Stop complaining everything is too hard and just do what needs to be done

@alloutoffucks but when you read the experts recommending this that’s exactly what they’re trying to avoid. By delaying and exposing only people at low risk who can fight the virus they protect those would would otherwise die. Therefore the death percentage drops dramatically. If everyone isolates it only take on infected person and we are back to ground zero. Most households and businesses can’t afford to shut down for an unlimited period