We haven't had a widespread flu problem since 2018. Yet despite it only being 2020, some insist this year's coronavirus must be the product of government scientists, though some also suggest it was the result of 5G cellular service in Wuhan. Then China claimed it might be the U.S.
What is the truth?
The novel SARS-CoV-2 coronavirus that emerged in the city of Wuhan is the product of natural evolution, finds an analysis of genome sequence data from SARS-CoV-2 and related viruses published today.
If a government were going to create something, it wouldn't be this. Though the virus is easy to transmit, coronavirus is in the same family as the common cold, it is hard to get COVID-19, and unless you have risk factors it won't be severe. That makes for a terrible pandemic, so no one would decide to make this in a laboratory. Yet it is causing a worldwide recession anyway.
"By comparing the available genome sequence data for known coronavirus strains, we can firmly determine that SARS-CoV-2 originated through natural processes," says Kristian Andersen, PhD, an associate professor of immunology and microbiology at Scripps Research and corresponding author on the new paper.
It's nature, that's why it's the third corona virus pandemic of the last 20 years
Coronaviruses are a large family of viruses that can cause illnesses ranging widely in severity. They were first categorized in the 1960s but obviously they were around long before that. The first known severe illness caused by a coronavirus emerged with the 2003 Severe Acute Respiratory Syndrome (SARS) epidemic in China. A second outbreak of severe illness began in 2012 in Saudi Arabia with the Middle East Respiratory Syndrome (MERS).
On December 31 of last year, Chinese authorities finally responded to concerns by medical personnel, one of whom later died despite being young, and alerted the World Health Organization that an outbreak of a novel strain of coronavirus causing severe illness was in Wuhan. The Wuhan Flu was subsequently given the subsequent designation SARS-CoV-2. As of February 20, 2020, nearly 167,500 COVID-19 cases have been documented, although many more mild cases have likely gone undiagnosed. The virus has killed over 6,600 people and led to worldwide concern even though flu will kill 10X as many. If even 6,000 died in the U.S. alone it would be the best flu season on record, so 70 deaths are not reason to panic, but the virus has the coasts of the U.S. telling people to stay in their homes.
Shortly after the problem was acknowledged, Chinese scientists sequenced the genome of SARS-CoV-2 and made the data available to researchers worldwide. The resulting genomic sequence data has shown that the number of COVID-19 cases have been increasing because of human to human transmission after a single introduction into the human population. That's what led to government conspiracy theories. In the new paper scientists used this sequencing data to explore the origins and evolution of SARS-CoV-2 by focusing in on several tell-tale features of the virus.
They analyzed the genetic template for spike proteins, armatures on the outside of the virus that it uses to grab and penetrate the outer walls of human and animal cells. More specifically, they focused on two important features of the spike protein: the receptor-binding domain (RBD), a kind of grappling hook that grips onto host cells, and the cleavage site, a molecular can opener that allows the virus to crack open and enter host cells.
Evidence for natural evolution
The scientists found that the RBD portion of the SARS-CoV-2 spike proteins had evolved to effectively target a molecular feature on the outside of human cells called ACE2, a receptor involved in regulating blood pressure. The SARS-CoV-2 spike protein was so effective at binding the human cells, in fact, that the scientists concluded it was the result of natural selection and not the product of genetic engineering.
This evidence for natural evolution was supported by data on SARS-CoV-2's backbone - its overall molecular structure. If someone were seeking to engineer a new coronavirus as a pathogen, they would have constructed it from the backbone of a virus known to cause illness. But the scientists found that the SARS-CoV-2 backbone differed substantially from those of already known coronaviruses and mostly resembled related viruses found in bats and pangolins.
So much for claims that it is a corporate or government conspiracy.
Two possible origins of the virus that don't involve corporate or government conspiracies
Based on their genomic sequencing analysis, Andersen and his collaborators concluded that the most likely origins for SARS-CoV-2 followed one of two possible scenarios.
In one scenario, the virus evolved to its current pathogenic state through natural selection in a non-human host and then jumped to humans. This is how previous coronavirus outbreaks have emerged, with humans contracting the virus after direct exposure to civets (SARS) and camels (MERS). The researchers proposed bats as the most likely reservoir for SARS-CoV-2 as it is very similar to a bat coronavirus. There are no documented cases of direct bat-human transmission, however, suggesting that an intermediate host was likely involved between bats and humans.
If so, both of the distinctive features of SARS-CoV-2's spike protein--the RBD portion that binds to cells and the cleavage site that opens the virus up--would have evolved to their current state prior to entering humans. In this case, the current epidemic would probably have emerged rapidly as soon as humans were infected, as the virus would have already evolved the features that make it pathogenic and able to spread between people.
In the other possible scenario, a non-pathogenic version of the virus jumped from an animal host into humans and then evolved to its current pathogenic state within the human population. For instance, some coronaviruses from pangolins, armadillo-like mammals found in Asia and Africa, have an RBD structure very similar to that of SARS-CoV-2. A coronavirus from a pangolin could possibly have been transmitted to a human, either directly or through an intermediary host such as civets or ferrets.
Then the other distinct spike protein characteristic of SARS-CoV-2, the cleavage site, could have evolved within a human host, possibly via limited undetected circulation in the human population prior to the beginning of the epidemic. The researchers found that the SARS-CoV-2 cleavage site, appears similar to the cleavage sites of strains of bird flu that has been shown to transmit easily between people. SARS-CoV-2 could have evolved such a virulent cleavage site in human cells and soon kicked off the current epidemic, as the coronavirus would possibly have become far more capable of spreading between people.
It is impossible to know which of the scenarios is most likely. If the SARS-CoV-2 entered humans in its current pathogenic form from an animal source, it raises the probability of future outbreaks, as the illness-causing strain of the virus could still be circulating in the animal population and might once again jump into humans. The chances are lower of a non-pathogenic coronavirus entering the human population and then evolving properties similar to SARS-CoV-2.