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> SARS-COV-2 has never been detected in any Chinese land animals associated with the market. They acted very quickly to sterilize the market which eliminated t

> SARS-COV-2 has never been detected in any Chinese land animals associated with the market. They acted very quickly to sterilize the market which eliminated the evidence. In SARS-1 the market associated with that was allowed to operate until investigators were able to take samples from the animals there and find the related virus. As a containment measure this was probably the right reflex to have, as an investigative measure this was highly counterproductive. If, however, you are one of the people who blame China for not acting fast enough to contain the spread then you can't criticize them for this. > There's no reservoir of the stuff found in the wild...unlike viruses like Ebola, Marburg, MERS, etc. MERS just happened to be very easy since we sampled the camels and they were positive and sitting right there with lots of human contact. In the case of SARS-1 the actual progenitor virus was only found 10 years later in bats in Yunnan. With Ebola the species that harbors the virus has actually yet to be determined, decades later. Marburg was first discovered in 1967 and was only isolated from Egyptian fruit bats in 2009, 42 years later. I think you're vastly underestimating how hard it is to track down animal reservoirs, and with the reservoir of Ebola still being unknown 46 years after it was discovered kind of undermines your entire point. We also now have the BANAL viruses found in bats in Laos which are getting closer and closer to a match to SARS-CoV-2, which is actually good progress after only 2-3 years (it would actually be highly suspicious if someone found the 99% homologous bat progenitor of SARS-CoV-2 after only a few years of looking, that would suggest that China knew where it was all along -- actual science that isn't on the TV or movies is quite difficult and usually a lengthy needle-in-a-haystack process as all of these examples show).

tripletao 4y ago
> In the case of SARS-1 the actual progenitor virus was only found 10 years later in bats in Yunnan. Why do you keep saying this? As you know, the closest animal viruses to SARS-1 were found in civet cats and raccoon dogs, within about a year of its emergence in humans. The bat viruses that Dr. Shi later discovered are scientifically important, because most of SARS-1's genome probably evolved in bats. They provide no new insight as to how the virus came to infect humans, though.
- lamontcg 4y ago
  WIV-1 can directly infect humans. So did civit cats and racoon dogs give us SARS-1 or did we infect them (or backwards and forwards as in the case of SARS-CoV-2 and mink)? If you go back a few months before the pandemic outbreak in humans and there's a zoonotic jump to civit cat and raccoon dogs then I don't think you can usefully call that the reservoir species. It existed and evolved for decades in bats, which I'd call the reservoir. The jump to the intermediate animal I'd consider to be part of the pandemic mechanism (unless you can find SARS-1 in samples from a decade previously in those animals). [ And another way to say this is why do we bother calling out an "intermediate species" when discussing pandemics? ]
  - tripletao 4y ago
    WIV-1 can infect human cells in vitro. No complete human infected with WIV-1 has ever been identified, living or dead. When SARS-1 emerged in humans, cases were concentrated among traders handling civet cats, as were positive antibody tests. That seems to me like a pretty strong case for forward zoonosis, maybe not perfect but certainly stronger than any evidence we have for SARS-CoV-2. I agree there's no evidence for any animal except bats as the reservoir for SARS-1 (or SARS-CoV-2). The intermediate host seems like the important link to show natural origin, though. Genetic engineers can't invent new viruses de novo, only modify existing ones, so a reservoir host must always exist; the question is just how it got from that reservoir to a human pandemic.
    - sudosysgen 4y ago
      If SARS-1 was more infectious and less virulent you wouldn't see cases concentrated amongst traders, would you? If anything, since many of them already have some kind of immunity from previous infection, you would not expect them to even notice being sick before the virus already infected thousands.
      - tripletao 4y ago
        I agree that finding the origin of a virus that's less deadly and faster-spreading (like SARS-CoV-2) is a harder problem. Nevertheless: 1. We quickly found pretty good evidence (infected civet cats and raccoon dogs, and infected human traders of those animals) that SARS-1 arose from natural zoonosis, within about a year of its emergence in humans. The later discovery of WIV-1 didn't add to this evidence. 2. We've found no such evidence for SARS-CoV-2. That doesn't mean SARS-CoV-2 definitely arose unnaturally--we've expended a lot more effort looking, but it really is a harder problem. It just means we don't know, and we need to keep looking. Do you disagree?
rich_sasha 4y ago
I'm not really disagreeing, but isn't comparing Ebola and Marburg to SARSes a bit apples-to-bananas? Ebola and Marburg for decades were quite rare. Incredibly deadly, but an outbreak would affect a few tens of people, and invariably in remote locations. By the time the epidemiologists arrived, the outbreak was waning. Clearly the Ebola outbreak in 2010s was much bigger, but that was the first such large outbreak. Also, with outbreaks in the rainforest, and perhaps with poor sanitation, there are thousands of possible animal hosts, whereas hyper-urbanised China hives far less opportunity for wildlife contact.
- sudosysgen 4y ago
  China is not "hyper-urbanised". There is still a good 30% rural population a lot of which live close to very dense forests with questionable sanitation. I don't understand how those viruses being rare in humans and outbreaks fading is actually making it harder to find them. If anything it is easier because then they don't have to figure out if humans gave it to them or they gave it to humans.
  - rich_sasha 4y ago
    Wuhan itself is 12 million people, 1,500 km^2 according to Wikipedia. I don't know but I'm guessing there is far less opportunities for coming up close with all sorts of wildlife. Id also guess the manpower that went into searching for the SARS2 predecessor far exceeds the efforts that went into sampling animals in African rainforest.
    - sudosysgen 4y ago
      The zoonotic theory is that the infected animals came from exactly the places where there is a lot of wildlife and were shipped to Wuhan (which is basically the point of wet markets). There might have been more manpower looking for the SARS-2 predecessor but, unlike with Ebola, there isn't any guarantee it still exists in a recognizable form, and in intermediate hosts you have the issue of human-animal transmission.

tripletao 4y ago

> In the case of SARS-1 the actual progenitor virus was only found 10 years later in bats in Yunnan. Why do you keep saying this? As you know, the closest animal viruses to SARS-1 were found in civet cats and raccoon dogs, within about a year of its emergence in humans. The bat viruses that Dr. Shi later discovered are scientifically important, because most of SARS-1's genome probably evolved in bats. They provide no new insight as to how the virus came to infect humans, though.

lamontcg 4y ago
WIV-1 can directly infect humans. So did civit cats and racoon dogs give us SARS-1 or did we infect them (or backwards and forwards as in the case of SARS-CoV-2 and mink)? If you go back a few months before the pandemic outbreak in humans and there's a zoonotic jump to civit cat and raccoon dogs then I don't think you can usefully call that the reservoir species. It existed and evolved for decades in bats, which I'd call the reservoir. The jump to the intermediate animal I'd consider to be part of the pandemic mechanism (unless you can find SARS-1 in samples from a decade previously in those animals). [ And another way to say this is why do we bother calling out an "intermediate species" when discussing pandemics? ]
- tripletao 4y ago
  WIV-1 can infect human cells in vitro. No complete human infected with WIV-1 has ever been identified, living or dead. When SARS-1 emerged in humans, cases were concentrated among traders handling civet cats, as were positive antibody tests. That seems to me like a pretty strong case for forward zoonosis, maybe not perfect but certainly stronger than any evidence we have for SARS-CoV-2. I agree there's no evidence for any animal except bats as the reservoir for SARS-1 (or SARS-CoV-2). The intermediate host seems like the important link to show natural origin, though. Genetic engineers can't invent new viruses de novo, only modify existing ones, so a reservoir host must always exist; the question is just how it got from that reservoir to a human pandemic.
  - sudosysgen 4y ago
    If SARS-1 was more infectious and less virulent you wouldn't see cases concentrated amongst traders, would you? If anything, since many of them already have some kind of immunity from previous infection, you would not expect them to even notice being sick before the virus already infected thousands.
    - tripletao 4y ago
      I agree that finding the origin of a virus that's less deadly and faster-spreading (like SARS-CoV-2) is a harder problem. Nevertheless: 1. We quickly found pretty good evidence (infected civet cats and raccoon dogs, and infected human traders of those animals) that SARS-1 arose from natural zoonosis, within about a year of its emergence in humans. The later discovery of WIV-1 didn't add to this evidence. 2. We've found no such evidence for SARS-CoV-2. That doesn't mean SARS-CoV-2 definitely arose unnaturally--we've expended a lot more effort looking, but it really is a harder problem. It just means we don't know, and we need to keep looking. Do you disagree?

rich_sasha 4y ago

I'm not really disagreeing, but isn't comparing Ebola and Marburg to SARSes a bit apples-to-bananas? Ebola and Marburg for decades were quite rare. Incredibly deadly, but an outbreak would affect a few tens of people, and invariably in remote locations. By the time the epidemiologists arrived, the outbreak was waning. Clearly the Ebola outbreak in 2010s was much bigger, but that was the first such large outbreak. Also, with outbreaks in the rainforest, and perhaps with poor sanitation, there are thousands of possible animal hosts, whereas hyper-urbanised China hives far less opportunity for wildlife contact.

sudosysgen 4y ago
China is not "hyper-urbanised". There is still a good 30% rural population a lot of which live close to very dense forests with questionable sanitation. I don't understand how those viruses being rare in humans and outbreaks fading is actually making it harder to find them. If anything it is easier because then they don't have to figure out if humans gave it to them or they gave it to humans.
- rich_sasha 4y ago
  Wuhan itself is 12 million people, 1,500 km^2 according to Wikipedia. I don't know but I'm guessing there is far less opportunities for coming up close with all sorts of wildlife. Id also guess the manpower that went into searching for the SARS2 predecessor far exceeds the efforts that went into sampling animals in African rainforest.
  - sudosysgen 4y ago
    The zoonotic theory is that the infected animals came from exactly the places where there is a lot of wildlife and were shipped to Wuhan (which is basically the point of wet markets). There might have been more manpower looking for the SARS-2 predecessor but, unlike with Ebola, there isn't any guarantee it still exists in a recognizable form, and in intermediate hosts you have the issue of human-animal transmission.