5 ms·

Yes - an animal host or reservoir is found. It's unusual after 2 years none has been found.

sudosysgen 5y ago
There are many animal hosts or reservoirs. The issue is that it's not obvious wether they got it from or gave it to humans. You really need the most direct ancestor virus.
- johncena33 5y ago
  AFAIK the known animal reservoirs got it from humans. Do you know any animal reservoir that we still don't know how the animals have got it?
  - sudosysgen 5y ago
    We don't, and that's the issue, we can't know unless we find an ancestor virus. It's also very possible if could have wiped out the original virus in all original reservoirs. It's very difficult to do this now and for endemic viruses in general, and it took a very very long time to do for SARS where this wasn't a problem.
    - neom 5y ago
      I thought they thought it might be pangolins? https://pubmed.ncbi.nlm.nih.gov/32380510/ https://pubmed.ncbi.nlm.nih.gov/32380510/
      - sudosysgen 5y ago
        Yeah, that's a theory, but I don't think it's settled yet
      - lamontcg 5y ago
        That is a very old article in pandemic research time. Pagolins aren't thought to be the likely intermediate animal any more.
- awb 5y ago
  A quick reminder of what scientists said in early 2020: https://www.theguardian.com/world/2020/apr/28/how-did-the-coronavirus-start-where-did-it-come-from-how-did-it-spread-humans-was-it-really-bats-pangolins-wuhan-animal-market https://www.theguardian.com/world/2020/apr/28/how-did-the-co... > “we really don’t know” how accurate the origin story is, she says: “There’s some sort of connection [to the Wuhan market] and there were people exposed to the market that were infected.” > Baker says what is “very likely” is that the virus originated in a bat. “It’s a likely scenario but we will never know. The market was cleaned up quite quickly. We can only speculate.” > “These wet markets have been identified as an issue because you do have species interacting,” she says. “It’s an opportunity to highlight the dangers of them and an opportunity to clamp down on them.” > Turner adds: “We’ve found the ancestors of the virus, but having broader knowledge of the coronavirus in other species might give us a hint about the evolution of this thing and how it jumped.” There has been other wet market origin stories as well, so I think absent other evidence it seemed like the Occam’s razor answer.
dopa42365 5y ago
Turned out that it's basically impossible to test just us 7.something billion humans. No one is out there testing a billion bats (or many more billions of mice and what not). Animal patient 0 is probably dead already anyway? Good luck with that search.
philjohn 5y ago
We still aren't 100% sure about Ebola's reservoir, so that isn't necessarily a smoking gun.
- tim333 5y ago
  Ebola didn't break out in a modern city of 10m + people.
lamontcg 5y ago
The progenitor of the SARS-1 outbreak in 2003 wasn't found until a decade later in 2013. There's a lot of research which is getting closer: https://www.researchsquare.com/article/rs-871965/v1 https://www.researchsquare.com/article/rs-871965/v1 https://www.nature.com/articles/s41467-021-21240-1 https://www.nature.com/articles/s41467-021-21240-1 https://www.frontiersin.org/articles/10.3389/fmicb.2020.584717/full https://www.frontiersin.org/articles/10.3389/fmicb.2020.5847... https://www.biorxiv.org/content/10.1101/2021.01.26.428212v1 https://www.biorxiv.org/content/10.1101/2021.01.26.428212v1 https://www.sciencedirect.com/science/article/pii/S1873506120304165 https://www.sciencedirect.com/science/article/pii/S187350612... https://www.researchsquare.com/article/rs-885194/v1 https://www.researchsquare.com/article/rs-885194/v1 https://www.adn.com/nation-world/2021/10/11/in-search-for-covid-origins-chinas-hubei-caves-and-wildlife-farms-draw-new-scrutiny/ https://www.adn.com/nation-world/2021/10/11/in-search-for-co...
- tim333 5y ago
  The immediate source - palm civets at a local market was found almost as soon as they looked, about four months after the outbreak. Tracing back where they got it from took longer.
  - lamontcg 5y ago
    After the discovery of WIV1 in bats it was found that it efficiently infected human airway epithelial cells, and since the palm civets were never linked to any outbreaks it is possible that the virus had directly hopped to humans from bats and that the palm civets were unnecessary as an intermediate species. It was also later found that it infects racoon dogs, ferret badgers and domestic cats. There was never any conclusive proof that raccoon dogs were responsible/required and that now looks unnecessary, which is a good example of how over a decade later what we think we know can change.
    - tripletao 5y ago
      I believe that: 1. The closest known animal viruses to human SARS-1 were found in civet cats in 2003, within about a year of the first discovery of the virus in humans. 2. No animal viruses closer to SARS-1 have since been discovered. Dr. Shi discovered various viruses in bats that we believe are ancestral to SARS-1, including WIV-1 in 2013. This is significant because we believe SARS-1 evolved primarily in bats, but those viruses have lower genetic identity with SARS-1 than does the virus found in the civets. If you disagree, please link a paper. Based on the above, I don't understand why you'd think 2013 is the important date. Within about a year of the emergence of both of the previous two novel coronaviruses in humans (SARS-1 and MERS), a near-identical virus was discovered in animals (civets and camels). This is suggestive but not conclusive evidence that those animals first infected humans, and strong evidence that those viruses existed in nature--somewhere, even if not exclusively in those animals--before they emerged in humans. For SARS-CoV-2, no such evidence has yet been found. This doesn't prove that SARS-CoV-2 is of unnatural origin, and I assume you'll mention the uncertainty in Ebola's zoonotic hosts shortly; but I don't see how anyone could treat that as irrelevant, except out of willful blindness.

There are many animal hosts or reservoirs. The issue is that it's not obvious wether they got it from or gave it to humans. You really need the most direct ancestor virus.

johncena33 5y ago
AFAIK the known animal reservoirs got it from humans. Do you know any animal reservoir that we still don't know how the animals have got it?
- sudosysgen 5y ago
  We don't, and that's the issue, we can't know unless we find an ancestor virus. It's also very possible if could have wiped out the original virus in all original reservoirs. It's very difficult to do this now and for endemic viruses in general, and it took a very very long time to do for SARS where this wasn't a problem.
  - neom 5y ago
    I thought they thought it might be pangolins? https://pubmed.ncbi.nlm.nih.gov/32380510/ https://pubmed.ncbi.nlm.nih.gov/32380510/
    - sudosysgen 5y ago
      Yeah, that's a theory, but I don't think it's settled yet
    - lamontcg 5y ago
      That is a very old article in pandemic research time. Pagolins aren't thought to be the likely intermediate animal any more.
awb 5y ago
A quick reminder of what scientists said in early 2020: https://www.theguardian.com/world/2020/apr/28/how-did-the-coronavirus-start-where-did-it-come-from-how-did-it-spread-humans-was-it-really-bats-pangolins-wuhan-animal-market https://www.theguardian.com/world/2020/apr/28/how-did-the-co... > “we really don’t know” how accurate the origin story is, she says: “There’s some sort of connection [to the Wuhan market] and there were people exposed to the market that were infected.” > Baker says what is “very likely” is that the virus originated in a bat. “It’s a likely scenario but we will never know. The market was cleaned up quite quickly. We can only speculate.” > “These wet markets have been identified as an issue because you do have species interacting,” she says. “It’s an opportunity to highlight the dangers of them and an opportunity to clamp down on them.” > Turner adds: “We’ve found the ancestors of the virus, but having broader knowledge of the coronavirus in other species might give us a hint about the evolution of this thing and how it jumped.” There has been other wet market origin stories as well, so I think absent other evidence it seemed like the Occam’s razor answer.

dopa42365 5y ago

Turned out that it's basically impossible to test just us 7.something billion humans. No one is out there testing a billion bats (or many more billions of mice and what not). Animal patient 0 is probably dead already anyway? Good luck with that search.

philjohn 5y ago

We still aren't 100% sure about Ebola's reservoir, so that isn't necessarily a smoking gun.

tim333 5y ago
Ebola didn't break out in a modern city of 10m + people.

lamontcg 5y ago

The progenitor of the SARS-1 outbreak in 2003 wasn't found until a decade later in 2013. There's a lot of research which is getting closer: https://www.researchsquare.com/article/rs-871965/v1 https://www.researchsquare.com/article/rs-871965/v1 https://www.nature.com/articles/s41467-021-21240-1 https://www.nature.com/articles/s41467-021-21240-1 https://www.frontiersin.org/articles/10.3389/fmicb.2020.584717/full https://www.frontiersin.org/articles/10.3389/fmicb.2020.5847... https://www.biorxiv.org/content/10.1101/2021.01.26.428212v1 https://www.biorxiv.org/content/10.1101/2021.01.26.428212v1 https://www.sciencedirect.com/science/article/pii/S1873506120304165 https://www.sciencedirect.com/science/article/pii/S187350612... https://www.researchsquare.com/article/rs-885194/v1 https://www.researchsquare.com/article/rs-885194/v1 https://www.adn.com/nation-world/2021/10/11/in-search-for-covid-origins-chinas-hubei-caves-and-wildlife-farms-draw-new-scrutiny/ https://www.adn.com/nation-world/2021/10/11/in-search-for-co...

tim333 5y ago
The immediate source - palm civets at a local market was found almost as soon as they looked, about four months after the outbreak. Tracing back where they got it from took longer.
- lamontcg 5y ago
  After the discovery of WIV1 in bats it was found that it efficiently infected human airway epithelial cells, and since the palm civets were never linked to any outbreaks it is possible that the virus had directly hopped to humans from bats and that the palm civets were unnecessary as an intermediate species. It was also later found that it infects racoon dogs, ferret badgers and domestic cats. There was never any conclusive proof that raccoon dogs were responsible/required and that now looks unnecessary, which is a good example of how over a decade later what we think we know can change.
  - tripletao 5y ago
    I believe that: 1. The closest known animal viruses to human SARS-1 were found in civet cats in 2003, within about a year of the first discovery of the virus in humans. 2. No animal viruses closer to SARS-1 have since been discovered. Dr. Shi discovered various viruses in bats that we believe are ancestral to SARS-1, including WIV-1 in 2013. This is significant because we believe SARS-1 evolved primarily in bats, but those viruses have lower genetic identity with SARS-1 than does the virus found in the civets. If you disagree, please link a paper. Based on the above, I don't understand why you'd think 2013 is the important date. Within about a year of the emergence of both of the previous two novel coronaviruses in humans (SARS-1 and MERS), a near-identical virus was discovered in animals (civets and camels). This is suggestive but not conclusive evidence that those animals first infected humans, and strong evidence that those viruses existed in nature--somewhere, even if not exclusively in those animals--before they emerged in humans. For SARS-CoV-2, no such evidence has yet been found. This doesn't prove that SARS-CoV-2 is of unnatural origin, and I assume you'll mention the uncertainty in Ebola's zoonotic hosts shortly; but I don't see how anyone could treat that as irrelevant, except out of willful blindness.