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Comment by thepasswordis | Hacker News Reader

Something which hasn't been able to be answered for me on this yet:

Where are all the bats infected with this virus? It it came from a bat, it would have had to be circulating in the bat population a LOT to mutate enough to jump to humans, right?

So...why not go find a bad, identify the parent virus, and close this whole thing out?

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The bats , horseshoe bats, located in caves approximately a thousand kilometers away have often carried these viruses. [0] And at least 6 times since the year 2000 the collection of these bats have led to humans getting sick. It just takes some fecal matter dust.

So a very likely explanation is some low level employees grabbed some bats, got their suits and vehicles contaminated didn't clean things properly, drove down to the Wuhan laboratory, and rested in town spreading virus contaminated dust or if they were already sick, their virus filled respiration about.

No lab leak needed, just the regular practices when "Wuhan Institute of Virology in China sampled thousands of horseshoe bats in locations across the country", and those doing so were being sloppy, as they have been known to be repeatably.

[0] Bat cave solves mystery of deadly SARS virus — and suggests new outbreak could occur - December 2017 https://www.nature.com/articles/d41586-017-07766-9

Exactly. There was an outbreak in a deserted mine in South China in the early 2000's, 6 cleaning workers got seriously ill with symptoms similar to current Corona. See e.g. https://www.frontiersin.org/articles/10.3389/fpubh.2020.5815...

The leader of the Wuhan team went there with a team to collect samples and animals. In the early days of Covid, those samples were re-examined and it turned out that the genome of the Covid strain was very similar to the Covid 19 virus. So the conclusion was taken that those bats must have been the origin where Corona somehow started. Somehow nobody at that time thought much about the fact that those samples were kept in Wuhan, exactly where the outbreak started.

Also,this sars cov-2 virus will not infect bats. That really hurts the 'it came from the bats' theory.

Define "will not infect bats".

Bats have a very unusual immune system in that they can harbor viruses without the virus killing the bat or the bat killing the virus.

It's one of the things that makes them ferociously good incubators for a cross-species mammalian plague. The other things are that they fly (so can cover larger distances than most mammals) and have communal living (so can transmit to each other very readily).

Similarly, humans can't impregnate chimpanzees. That really hurts the "humans evolved from apes" theory

Since this is a common misconception, I'll note that humans didn't evolve from apes or chimpanzees. We share a relatively close common ancestor with them.

Ape is a broad enough term (& fuzzy) that depending on context humans could be considered included or excluded from the category, meanwhile chimps & that common ancestor do fit into the category

Hence I didn't say we evolved from chimpanzees, even though it'd've suited the snow clone better

That’s not how viruses work.

It's a possible explanation, but that doesn't mean it's "very likely". In that case it would be easy enough to drive back down to the cave and collect the missing evidence of bat origin. Better yet, you'd never have to disclose the low-level employee part, so there'd be no political fallout. Easy win.

Also, my understanding (quite possibly wrong) is that while humans can get sick from bats, as cave workers did in Southern China, those viruses aren't contagious in the sense that the sick humans go on to infect others. "Since no case of an epidemic caused by direct bat-to-human transmission has yet been demonstrated, it is thought that the transfer to humans more probably took place via an intermediate host species in which the virus could evolve and move towards forms likely to infect human cells." [1] If that's right then your explanation of spilled bat samples is incomplete: it doesn't explain what caused the bat samples to adapt into a form that could spread among humans. That sort of puts us back at square 1. Another way of saying this is that if your explanation is likely, then we'd have expected the pandemic to have started where the bats are - through sick cave workers or something similar. But in fact it started far away.

[1] https://news.cnrs.fr/articles/the-origin-of-sars-cov-2-is-be...

That is what exactly I think the Wuhan labs was studying, given that SARS did jump from another animal to human very recently. What would happen if these things mutate naturally and infect humans? They add gain-of-function genes to a near relative, study how it infect cells and come up with a plan to treat it. Except someone dropped some stuff on their shoe and went out shopping to the wet market.

I did plenty of these gain-of-function experiments in my postgrad studies. Mice tumours cells given genes to super-express certain cell adhesion molecules. Without this kind of approach, it is difficult to impossible to study these reactions. You just gotta be careful.

That is one of the points in the article in favour of a lab leak hypothesis. People have been searching for an animal host (not necessarily a bat, could be an intermediate host) for over a year now and haven't found anything. The animal host for SARS1 was found in four months.

For SARS (2003) It took 3 years to find the intermediate host (civets). And 14 years (2017) to find the bat parent of the virus[1].

[1]https://en.wikipedia.org/wiki/Severe_acute_respiratory_syndr...

Guess who found the bat host? Shi Zhengli of the very WIV in question.

That wikipedia article says

> In late May 2003, studies were conducted using samples of wild animals sold as food in the local market in Guangdong, China. The results found that the SARS coronavirus could be isolated from masked palm civets (Paguma sp.)

and

> The SARS epidemic began in the Guangdong province of China in November 2002 ... Chinese government officials did not inform the World Health Organization of the outbreak until February 2003.

That's six months from the start of the outbreak, and less than four months from WHO being informed, not three years.

Where did you get your "three years" figure from?

That's a bit confusing because the OP makes an opposite point: "The intermediary host species of SARS1 was identified within four months of the epidemic’s outbreak, and the host of MERS within nine months."

In 2003 it was merely suspected that covers were the intermediate. It wasn't confirmed until 2006. Read further down:

"In late 2006, scientists from the Chinese Centre for Disease Control and Prevention of Hong Kong University and the Guangzhou Centre for Disease Control and Prevention established a genetic link between the SARS coronavirus appearing in civets and humans, bearing out claims that the disease had jumped across species.[62]"

It goes on to state that the bat link was confirmed in 2017.

It's pretty unclear exactly what was proved in 2003 and in 2006. But the point remains: for COVID19, after a year of searching we don't even have a suspect animal host.

Sars reemerged twice between 2003 and 2006, once in 2004 from civets and once in 2005 from an accidental lab release. Another potential outbreak in 2005 was prevented by preemptively culling civets when a high titre of SARS coronavirus was discovered. And civets eventually lead to the actual source on bats.

https://www.wsj.com/articles/SB107456233748805972

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