How did COVID-19 originate?
There are two theories:
1. COVID-19 was transferred to humans from contaminated animals at an out-door Wuhan market.
2. COVID-19 is the result of a leak in a Chinese research laboratory, either accidentally or on purpose.
Fact-checkers have been busy debunking the second view, but not always for the reasons you might think. Problem is that those who think it is manmade often present pertinent information and then dilute their validity with charges of Chinese conspiracy or bioweapons research.
As a result, fact-checkers invalidate the story and Youtube and Facebook ban it.
What do we know? Let's take a look.
The official view from the Center for Disease Control (CDC) is that the novel coronavirus started at the Huanan Seafood Market in Wuhan, China – an open-air market selling fish, meat and exotic wildlife. It is suspected the virus was transferred from a bat to an intermediary animal like a pangolin and then to a human.
SARS, MERS, and SARS-CoV-2 (aka COVID-19) are zoonotic, which means they can be transmitted between animals and people. Bats are not the only known carriers of viruses. The plague was carried by rodents and HIV spilled over from chimpanzees. Experts estimate animals are responsible for about 60 percent of human infectious diseases.
While bats were the first suspected source of the virus, experts believe it may have been transmitted to humans through an intermediary animal like a pangolin. Pangolins are long-snouted, ant-eating mammals often used in traditional Chinese medicine.
Two researchers at South China Agricultural University in Guangzhou, Shen Yongyi and Xiao Lihua, identified the pangolin as the potential source of nCoV-2019 on the basis of a genetic comparison of coronaviruses taken from the animals and from humans infected in the outbreak. The sequences are 99% similar, the researchers reported at a press conference in February.
Scientists say that the suggestion, based on a genetic analysis, seems plausible — but caution that the researchers’ work is yet to be published in full.
Moreover, the genetic sequence of the virus seems to confirm COVID-19 as naturally occurring rather than genetically altered.
A group of researchers compared the genome of this novel coronavirus with the seven other coronaviruses known to infect humans: SARS, MERS and SARS-CoV-2, which can cause severe disease; along with HKU1, NL63, OC43 and 229E, which typically cause just mild symptoms.
In the March 17 journal Nature Medicine, the researchers wrote: "Our analyses clearly show that SARS-CoV-2 is not a laboratory construct or a purposefully manipulated virus.
A research team at Scripps Research concurred that evidence pointed to a natural source.
Kristian Andersen, associate professor of immunology and microbiology at Scripps Research, and his colleagues looked at the genetic template for the spike proteins that protrude from the surface of the virus. The coronavirus uses these spikes to grab the outer walls of its host's cells and then enter those cells. They specifically looked at the gene sequences responsible for two key features of these spike proteins: the grabber, called the receptor-binding domain, that hooks onto host cells; and the so-called cleavage site that allows the virus to open and enter those cells.
Analysis showed that the "hook" part of the spike had evolved to target a receptor on the outside of human cells called ACE2, which is involved in blood pressure regulation. It is so effective at attaching to human cells that the researchers said the spike proteins were the result of natural selection and not genetic engineering.
OR WAS COVID-19 GENETICALLY ENGINEERED?
However, there are things that don’t add up say those who suspect it might have been produced in a lab.
Neither bats nor pangolins are listed on the inventory of items sold in the Wuhan market. The illegality of trading pangolins could explain this omission. Pangolins are protected animals, but illegal trafficking is widespread. Under Chinese law, people selling pangolins can be punished by 10 years or more in prison.
Some of the first patients had no contact with the market. A research article published by a large group of Chinese researchers in The Lancet shows that 13 of the first 41 patients diagnosed with the infection had no link to the market.
'It seems clear that the seafood market is not the only origin of the virus,' says Bin Cao of Capital Medical University, a pulmonary specialist and the corresponding author of The Lancet article.
The “smoking gun” for many seems to be the proximity of Chinese labs doing research on bats and coronaviruses.
Just 300 yards away from the market is the Wuhan Center for Disease Control and Prevention and 20-miles away is the Wuhan Institute of Virology, which was studying coronaviruses in bats as part of a $3.7 million grant from the U.S. National Institute of Health. The grants, awarded in 2014 and 2019, were paid through a subsidiary of NIH, the National Institute of Allergy and Infectious Diseases.
Dr. Anthony Fauci, a member of the coronavirus task force, is director of the NIAID.
There were hundreds of bats in Wuhan’s labs when the 2019-nCoV outbreak started, and the researchers there were studying at least 11 new strains of SARS-related viruses in them.
The Institute of Virology is a biosafety level 4 (BSL–4) laboratory constructed in 2015. Even so, there has been speculation that viruses may have accidentally leaked out.
A paper, attributing the outbreak to the China biolab, was published by scientists, Botao Xiao and Lei Xiao, in February on the international scholarly database Research Gate. The paper was quickly censored by Chinese authorities and removed from the site. However, an archive copy is still available with, of course, no peer review. Shortly thereafter, China tightened security on the labs.
Are these all just coincidences?
Shi Zhengli, who is deputy director of the institute and a highly respected Chinese virologist, told the press in February that she 'guaranteed with her own life' that the outbreak was not related to the lab.
Shi told the science journal Scientific American of her relief when, having checked back through disposal records, none of the genome sequences matched their virus samples.
Shi's team released its data identifying the disease on January 23 on a scientific portal before publication the next month by the journal Nature. It said the genomic sequence was 96 per cent identical to another virus they found in horseshoe bats in Yunnan, which supports the first theory.
WHERE DOES THIS LEAVE US?
Basically, we are still without an answer. Neither theory is conclusive. And until further study is done and more is known, we cannot make a definitive answer.
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