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Related: About this forumCovid origin studies say evidence points to Wuhan market
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The Huanan Seafood Wholesale Market in Wuhan was the early epicenter of the COVID-19 pandemic (Science)
The molecular epidemiology of multiple zoonotic origins of SARS-CoV-2 (Science)
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Source: BBC
Covid origin studies say evidence points to Wuhan market
By Victoria Gill
Science correspondent, BBC News
26 July 2022
Scientists say there is "compelling evidence" that Wuhan's Huanan seafood and wildlife market was at the centre of the Covid-19 outbreak.
Two peer-reviewed studies published on Tuesday re-examine information from the initial outbreak in the Chinese city.
One of the studies shows that the earliest known cases were clustered around that market.
-snip-
Together, the researchers say this evidence paints a picture that Sars-Cov-2 was present in live mammals that were sold at Huanan market in late 2019. They say it was transmitted into people who were working or shopping there in two separate "spillover events", where a human contracted the virus from an animal.
-snip-
Read more: https://www.bbc.com/news/science-environment-62307383
flying_wahini
(8,011 posts)After all the OG SARS was found in camels prior to other animals.
xocetaceans
(3,943 posts)...it's not either SARS-CoV/SARS-CoV-1 or SARS-CoV-2.
So, there's SARS-CoV/SARS-CoV-1, SARS-CoV-2 and MERS-CoV.
This talks about the genomes of SARS-CoV-1 and MERS-CoV:
The Baric laboratory studies lethal human coronaviruses, specifically Middle East Respiratory Syndrome Coronavirus (MERS-CoV) and Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV). These viruses are positive-sense, single-stranded RNA viruses that cause severe to lethal atypical pneumonias in humans. Overall mortality in the SARS-CoV epidemic was 9%; however, this rate increased to ~50% in males over the age of 50. The overall mortality of the MERS-CoV epidemic is ~40% of currently reported cases, although underreporting of the total number of cases is suspected.
...
https://www.med.unc.edu/orfeome/projects/genomic-comparison-of-mers-cov-sars-cov/
This talks about the animals in which SARS-CoV/SARS-CoV-1 was found:
Zhengli Shi, Zhihong Hu
Abstract
In this review, we summarize the researches on animal reservoirs of the SARS coronavirus (SARS-CoV). Masked palm civets were suspected as the origin of the SARS outbreak in 2003 and was confirmed as the direct origin of SARS cases with mild symptom in 2004. Sequence analysis of the SARS-CoV-like virus in masked palm civets indicated that they were highly homologous to human SARS-CoV with nt identity over 99.6%, indicating the virus has not been circulating in the population of masked palm civets for a very long time. Alignment of 10 complete viral genome sequences from masked palm civets with those of human SARS-CoVs revealed 26 conserved single-nucleotide variations (SNVs) in the viruses from masked palm civets. These conserved SNVs were gradually lost from the genomes of viruses isolated from the early phase to late phase human patients of the 2003 SARS epidemic. In 2005, horseshoe bats were identified as the natural reservoir of a group of coronaviruses that are distantly related to SARS-CoV. The genome sequences of bat SARS-like coronavirus had about 88-92% nt identity with that of the SARS-CoV. The prevalence of antibodies and viral RNA in different bat species and the characteristics of the bat SARS-like coronavirus were elucidated. Apart from masked palm civets and bats, 29 other animal species had been tested for the SARS-CoV, and the results are summarized in this paper.
...
A breakthrough came in May of 2003 when viruses related to SARS were identified in animals. A team led by Yi Guan (Hong Kong University) and colleagues from the Center for Disease Control (CDC) Shenzhen, studied 25 individuals from 8 different species including 6 masked palm civets (Paguma larvata), 1 raccoon dog (Nyctereutes procyonoides), 2 Chinese ferret-badgers (Melogale moschata), 3 hog-badgers (Arctonyx collaris), 3 beavers (Castor fiber), 4 domestic cats (Felis catus), 3 Chinese hares (Lepus sinensis) and 2 Chinese muntjac (Muntiacus reevesi) gathered in Dongmen Market, Shenzhen, Guangdong Province (Guan et al., 2003).
...
https://www.sciencedirect.com/science/article/pii/S0168170207001050?via%3Dihub
PSPS
(14,136 posts)The only reason these stories keep having to be repeated is that putin and his puppets in the us government keep the "chinese lab leak" silliness alive, which is breathlessly repeated on the far-right media wurlitzer.
xocetaceans
(3,943 posts)May 30, 2021
Robert Garry joins TWiV to explain how the molecular biology of SARS-CoV-2 shows that it came from Nature and not a lab, including the receptor binding domain, the furin cleavage site, and the two lineages circulating in Wuhan wildlife markets.
https://www.microbe.tv/twiv/twiv-762/
Tomconroy
(7,611 posts)"We're now as sure as we can be, based on the fragmentary evidence we do have, that this was a spillover event that happened in the market."
And why are these hypotheses based on only fragmentary evidence? Ask the Chinese government that won't allow any inquiries about Covid to be conducted.
There can never be a competent investigation into the origins of Covid without the cooperation of China.
xocetaceans
(3,943 posts)What kind of evidence would be counted as non-fragmentary?
It seems that finding an animal reservoir in nature is not always possible. So, drawing a straight line from an animal in nature to an animal in the market would be a very difficult thing to accomplish.
That's why the above question is a retort to your question. Absolute certainty regarding the exact time and place of the initial zoonotic event is not easily to be had.
Why We Dont Know the Animal Origins of the Coronavirus
Viruses that spill over to people do not stick around in animals, so finding true sources takes years of careful work, an expert says
By Christine K. Johnson on June 9, 2021
Over the past century, many notable viruses have emerged from animals to cause widespread illness and death in people. The list includes the pathogens behind pandemic influenza, Ebola, Zika, West Nile fever, SARS and now COVID, brought on by the virus SARS-CoV-2. For all of these microbes, the animal species that served as the original source of spillover was hard to find. And for many, that source still has not been conclusively identified. Confirming the circumstances and key participants involved in the early emergence of an infectious disease is a holy grail of this type of scientific inquiry: difficult to track and even more difficult to prove.
In ideal conditions, the first human cases involved in a zoonotic disease spillover (when a pathogen jumps from animals to humans) are reported in connection to animals present at the time of the event. This happens when the cluster of cases is large enough to be investigated and reported. But it is not necessarily the first time spillover occurred. Most spillovers are limited to more narrow animal-to-human cases. Once pathogens start to spread by human-to-human transmission, the tracks leading back to the initial animal source grow faint and become nearly impossible to follow.
Thus, animal sources for viruses that cause pandemics often remain shrouded in mystery. For some viruses, animal sources have been implicated after years or decades of large-scale international investigations. For other viruses, animal sources are highly suspected, but enough evidence has yet to be produced to pinpoint an exact species or range of species. Typically, lines of evidence are drawn over time through a trove of peer-reviewed publications, each building on the research that came before it, using more precise methods to narrow the field of possible sources. The scientific process is naturally self-correcting. Often seemingly contradictory hypotheses can initially flood the field, especially for high-impact outbreaks. But eventually, some of them are ruled out, and lines of investigation are narrowed.
Frequently, this investigative research only points to a group of suspected species, possibly a few most likely genera or, more often, an entire taxonomic order. That is because the virus has not actually been found in the suspected animal source in such cases. The evidence instead revolves around closely related viruses or their most recent common ancestors, based on inferred evolutionary history. If a virus was found in animal samples after the same pathogen caused widespread transmission among humans, it is possible that the virus spilled from humans back into animals. That happens often enough with viruses that can infect a range of animal species that the possibility needs to be presumed until it is ruled out.
...
https://www.scientificamerican.com/article/finding-conclusive-animal-origins-of-the-coronavirus-will-take-time/
Tomconroy
(7,611 posts)evidence of consciousness of guilt.
The Biden administration issued a statement on this issue last summer. You should read it.
https://www.whitehouse.gov/briefing-room/statements-releases/2021/08/27/statement-by-president-joe-biden-on-the-investigation-into-the-origins-of-covid-%E2%81%A019/
xocetaceans
(3,943 posts)That excerpt from the Presidential statement is quite true, but China and its internal politics prevented that from happening as early as it was needed. That is well known.
Generally, though, that linked Presidential statement is not very specific with respect to the information it is requesting - other than total openness and everything. The request sounds quite reasonable and is also quite understandable. (After all, who does not want to know?)
However, even though total openness could in principle possibly lead to an answer to the question as to the origin of the pandemic virus, it also might not lead to such an answer (as noted upthread). Sure, one should continue to attempt to investigate what happened in Wuhan, but those investigations will likely only substantively concern Chinese internal politics and the local Chinese leaders' desire not to admit to their national leaders that there was an outbreak in Wuhan. It won't concern a lab-leak theory which seems to not hold water - see below. (However, if you can personally dispute the (Robert Garry's) stated analysis of the genome, please tell me explicitly where the analysis is incorrect.)
Here's that discussion on the SARS-CoV-2 genome:
Here's another good discussion that frames the issue with background information:
Tomconroy
(7,611 posts)PoindexterOglethorpe
(26,727 posts)the sun rose in the east this morning.
Yeah, this was out there at the very beginning, and the idea that it came from a lab is nonsense.