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[Reelya]

I remember reading about the thing where malaria killed 50% of all the people who ever lived, looked into it and couldn't find a decent source for that.

https://www.realclearscience.com/blog/2019/10/03/has_malaria_really_killed_half_of_everyone_who_ever_lived.html

BBC journalist Tim Harford was skeptical, too. For his podcast, More or Less, he interviewed Professor Brian Faragher, Emeritus Professor of Medical Statistics at Liverpool School of Tropical Medicine.

"It's difficult to find evidence to support that claim. It's a widely published claim, but it's very difficult to find the source of it," Faragher said.

Indeed, the claim is made in articles from a wide array of traditionally credible sources, most without a link to an original source. Its earliest utterance we discovered is in a 2002 Nature article, unfortunately unreferenced: "Malaria may have killed half of all the people that ever lived."

That same year, two researchers explored the "Evolutionary and Historical Aspects of the Burden of Malaria" in the journal Clinical Microbiology Reviews. They wrote:

    "At some time during the 19th century, malaria reached its global limits. In absolute numbers and in the proportion of the humanity now affected, malaria was exacting its highest ever toll of sickness and death. Well over one-half of the world's population was at significant risk from malaria. Of those directly affected by malaria at least 1 in 10 could expect to die from it."

So, even if all of the world's population in 1900 contracted malaria, the death toll would have come to perhaps 100 million. That's a lot of people, but it would have taken 540 more "1900s" to get to 54 billion deaths, an almost statistically impossible prospect.

So what they're saying there is that half were at risk of malaria, but this was "at its global limits". Someone else then turned that into a catch-phrase of "half of everyone ever, died of malaria". It's bullshit basically.

What the likely source actually says is that 50% of people were "at-risk" of getting it, and that malaria had a death rate, if you catch it, of 10%. That's at most ... 5% of the population dying from malaria, assuming 100% of at-risk people actually catch malaria, so the total is probably 2.5% died of malaria or in that ballpark, not 50%.

So, it's basically one of those viral "science facts" which no clear traceable origins. I guess if we could use more than 10% of our brains, it would be easier to prevent these baseless memes from spreading.

[mko]

Thanks for fact checking!

When I was checking it last time I found http://factmyth.com/factoids/malaria-killed-half-the-people-who-have-ever-lived/

The factoid is close to true, but, at the end of the day, it is too much of a guesstimate/generalization to be declared a fact. While we don’t know exactly how many died from Malaria throughout history, we can safely say, “Malaria could have potentially killed nearly to half the people who ever lived, predominantly children”.

So I though that with "it is an estimate/guess and we have no accurate data about prehistoric (and even historic) deaths" or similar disclaimer it is OK to mention it.

Maybe

"Malaria killed billions of people. From about 5% to about 50% of all people who ever lived (uncertain data is uncertain)".

would be better?

I need to check more of it,

At some time during the 19th century, malaria reached its global limits. In absolute numbers and in the proportion of the humanity now affected, malaria was exacting its highest ever toll of sickness and death.

was surprising to me. I though that early in the human history proportion was even greater (for example when humans were limited to Africa).

[Reelya]

Malaria could have potentially killed nearly to half the people who ever lived

This bit is very vague though. There's a big difference between say "half of all people could potentially be murdered" vs "half all people who died were probably murdered". They're two different things.

Note that in the early 20th century there were a peak of about 2 million malaria deaths per year mostly in places where there was no treatment, but they need 5.5 million deaths per year, for every year between 800 BC to 1900 AD to add up to the 50 billion required deaths. So, even at peak deaths it was only about 40% of the required death rate for that year.

And we also gotta take into account world population growth, since any death rate is per-capita, and there were only around 200 million people in 1AD vs 1.6 billion by 1900. The numbers just don't add up. There was literally no year in existence in which the number of malaria deaths added up to 50% of all deaths, from what I can work out, so if it's untrue for all individual years, logically it can't be true when you aggregate all years.

So while it's "potentially a true statement" they're not talking about the numbers being close, or in the same ballpark to 50%, what they mean is that saying "malaria is one of the biggest killers in history" is still true, even if the "50% of all deaths" bit is wildly inaccurate.

[Jopax]

Things have gotten odd here in the past two days. It started on Thursday when they announced that they'd be lifting the limits on moving between counties (previously you had to have a permit, usually from your workplace, but it seemed they were fairly easy to get and you didn't really need to be in an essential position or anything) starting on Friday. Then, Friday morning they announce that younger and older folks will be allowed outside on alternating days (previously very young kids and folks older than 65 weren't supposed to be out in the cities at all). Finally, also on Friday, just after noon, they announce the curfew is officially over, with only the previously mentioned young and old having to go by the alternating days out scheme.

Granted we've been having it fairly easy here, only a handful of cases, and even those were due to people being goddamn idiots thinking rules don't apply to them. Still feels kinda weird to be able to just go out in the evening, and understandably folks are out and about in force today.

[Iduno]

The political ruling class having to eat a big assed dish of crow as everyone dies left and right, will of course-- STILL FAIL TO UNDERSTAND that failure to properly regulate and fund healthcare is what caused this whole mess.

They knew how bad it was when it hit China, and lied about the disease so they could sell off their stocks and profit from the suffering. They fully understand what they're doing.

[hector13]

So the BBC have a big headline on a live update thing saying the WHO aren't finding evidence that recovering from coronavirus imparts immunity, but I can't find anything beyond that headline.

That's super scary stuff if true.

Edit: Never mind, found what they linked to on the WHO website.

The development of immunity to a pathogen through natural infection is a multi-step process that typically takes place over 1-2 weeks. The body responds to a viral infection immediately with a non-specific innate response in which macrophages, neutrophils, and dendritic cells slow the progress of virus and may even prevent it from causing symptoms. This non-specific response is followed by an adaptive response where the body makes antibodies that specifically bind to the virus. These antibodies are proteins called immunoglobulins. The body also makes T-cells that recognize and eliminate other cells infected with the virus. This is called cellular immunity. This combined adaptive response may clear the virus from the body, and if the response is strong enough, may prevent progression to severe illness or re-infection by the same virus. This process is often measured by the presence of antibodies in blood.

WHO continues to review the evidence on antibody responses to SARS-CoV-2 infection.2-17 Most of these studies show that people who have recovered from infection have antibodies to the virus. However, some of these people have very low levels of neutralizing antibodies in their blood,4 suggesting that cellular immunity may also be critical for recovery. As of 24 April 2020, no study has evaluated whether the presence of antibodies to SARS-CoV-2 confers immunity to subsequent infection by this virus in humans.

At this point in the pandemic, there is not enough evidence about the effectiveness of antibody-mediated immunity to guarantee the accuracy of an “immunity passport” or “risk-free certificate.” People who assume that they are immune to a second infection because they have received a positive test result may ignore public health advice. The use of such certificates may therefore increase the risks of continued transmission. As new evidence becomes available, WHO will update this scientific brief.

[Dunamisdeos]

That sounds like they're worried that people who have recovered might still be carriers for a time, and then start spreading it again.

[Reelya]

You've misread that. They're talking about giving people “immunity passport” or “risk-free certificate.” because they've already had the disease, but they aren't actually antibody-positive, so they might catch it again, and since they've had it once they might feel over-confident to ignore safety measure such as social distancing.

This is nothing to do with being latent carriers.

[Dunamisdeos]

However, some of these people have very low levels of neutralizing antibodies in their blood,4 suggesting that cellular immunity may also be critical for recovery.

As of 24 April 2020, no study has evaluated whether the presence of antibodies to SARS-CoV-2 confers immunity to subsequent infection by this virus in humans.

People who assume that they are immune to a second infection because they have received a positive test result may ignore public health advice. The use of such certificates may therefore increase the risks of continued transmission.

I don't think so. They have low levels, not no levels. They should at least be resitant. Furthermore, MOST of them ARE showing full expected antibodies. No study has been done, so they aren't sure if this means some people are still non-immune. Finally, they are worried that these people are using the idea of their own immunity to spread it further.

So it's not that they aren't finding evidence that you aren't immune afterwards. A minority might not be. They aren't sure yet. They'll give us more info when they have it.

Concerning, to be sure.

[MetalSlimeHunt]

I don't think so. They have low levels, not no levels. They should at least be resistant.

Microbiology man said "fuck logic"

[Reelya]

So it's not that they aren't finding evidence that you aren't immune afterwards. A minority might not be. They aren't sure yet. They'll give us more info when they have it.

Concerning, to be sure.

That wasn't my point at all. you said the concern was that they're still carriers. It isn't, that's a total misreading of the article.

This sentence for example:

People who assume that they are immune to a second infection because they have received a positive test result may ignore public health advice. The use of such certificates may therefore increase the risks of continued transmission.

Isn't about people still being infected, it's about people who've been infected once ignoring public health advice since as stated they "assume that they are immune", and thus putting themselves at risk of a new infection, and then spreading it on. The phrase "second infection" is the key difference. The idea here is that if people who aren't actually strongly antibody-active start being given special "you're safe" certificates since they tested negative, they might behave in high-risk ways and pick up a new (second) infection.

Sure, you can argue it's unlikely, but it means your statement "That sounds like they're worried that people who have recovered might still be carriers for a time" isn't actually correct. No, it's not what they were worried about, because it's not what they were talking about whatsoever.

[feelotraveller]

Some 'interesting' survey results in US.  https://www.usatoday.com/story/news/politics/2020/04/24/coronavirus-one-third-us-believe-vaccine-exists-is-being-withheld/3004841001/

32% of those surveyed believed that it is at least probable that a vaccine exists but is being withheld from the public.
44% believe that it is at least probable that coronavirus was created in a lab.

[Iduno]

Some 'interesting' survey results in US.  https://www.usatoday.com/story/news/politics/2020/04/24/coronavirus-one-third-us-believe-vaccine-exists-is-being-withheld/3004841001/

32% of those surveyed believed that it is at least probable that a vaccine exists but is being withheld from the public.
44% believe that it is at least probable that coronavirus was created in a lab.

Look, 45% of people in the US admit they believe in ghosts, and they're all dumb as hell. 32% here is nothing.

[Reelya]

Of course the vaccine and lab thing are both false.

There is no coronavirus, it's test of a digital kill-switch using 5G Wifi and primed by chemtrails. If the conglomerate decides you're a problem, they flip the switch. This is the test run. Destroy the 5G towers while you can.

[Il Palazzo]

Preposterous. Of course there is coronavirus - that's what all those chemtrails were seeding all those years. Now that they've done their job, there's no need fore any more chemtrails. That's why the skies are clear now.